Growth differentiation factor 11 (GDF11) and myostatin (MSTN) are closely related TGFβ family members that are often believed to serve similar functions due to their high homology. However, genetic studies in animals provide clear evidence that they perform distinct roles. While the loss of Mstn leads to hypermuscularity, the deletion of Gdf11 results in abnormal skeletal patterning and organ development. The perinatal lethality of Gdf11-null mice, which contrasts with the long-term viability of Mstn-null mice, has led most research to focus on utilizing recombinant GDF11 proteins to investigate the postnatal functions of GDF11. However, the reported outcomes of the exogenous application of recombinant GDF11 proteins are controversial partly because of the different sources and qualities of recombinant GDF11 used and because recombinant GDF11 and MSTN proteins are nearly indistinguishable due to their similar structural and biochemical properties. Here, we analyze the similarities and differences between GDF11 and MSTN from an evolutionary point of view and summarize the current understanding of the biological processing, signaling, and physiological functions of GDF11 and MSTN. Finally, we discuss the potential use of recombinant GDF11 as a therapeutic option for a wide range of medical conditions and the possible adverse effects of GDF11 inhibition mediated by MSTN inhibitors.
Cytokines of the transforming growth factor β (TGFβ) family, including activins, growth differentiation factors (GDFs), bone morphogenetic proteins (BMPs), and TGFβs, have been extensively implicated in the regulation of developmental patterning, cellular proliferation and differentiation, and the maintenance of tissue homeostasis1. Among the TGFβ family members, there are two highly homologous proteins, GDF11 and myostatin (MSTN), which share 89% sequence identity in their mature form but exhibit distinct endogenous functions. While Gdf11 is expressed broadly in numerous tissues, Mstn is expressed primarily in skeletal muscle2,3,4. The functional divergence of GDF11 and MSTN is indicated by the fact that their mutation in animals leads to the development of largely dissimilar features. For instance, while the genetic deficiency of MSTN leads to a hypermuscular phenotype in various species4,5,6,7,8, homozygous deletion of Gdf11 generates defects in axial skeletal patterning and organ development in mice9. However, unlike the relatively consistent reports of the function of MSTN in suppressing skeletal muscle growth, the reports of GDF11 function, particularly those examining the postnatal role of GDF11, remain highly controversial. One of the main reasons for this controversy lies in the fact that Gdf11-null mice, unlike Mstn-null mice, show perinatal lethality9, leading most studies to utilize recombinant proteins that cannot fully recapitulate the complex endogenous functions of GDF11. Importantly, in contrast to studies that utilized recombinant GDF11 or MSTN proteins, those that applied genetic knockdown, knockout, or conditional knockout techniques revealed relatively unvarying results despite their being fewer in number, and most have reported the positive roles of GDF11 and the negative roles of MSTN in the regulation of the development of various tissues. In this review, we first present the similarities and differences between GDF11 and MSTN from an evolutionary point of view and summarize the insights obtained to date regarding the biological processing, signaling mechanisms, and physiological functions of GDF11 and MSTN during development, adulthood, and aging. We also discuss the potential of recombinant GDF11 protein as a therapeutic option for various clinical conditions and the possible adverse effects of GDF11 inhibition mediated by MSTN inhibitors.
Evolution and biology of GDF11 and MSTN
Evolutionary analysis of GDF11 and MSTN
The remarkable sequence similarity between GDF11 and MSTN has led to the assumption that they were derived from the same ancestral gene through gene duplication. Indeed, analysis of multiple invertebrate species revealed that they harbor a single homologous gene corresponding to GDF11 and MSTN10. For instance, in Caenorhabditis elegans, daf-7 was shown to encode a homolog of GDF11 and MSTN, while in fruit flies (Drosophila melanogaster), myoglianin (Myo) was found to exhibit the highest sequence homology to GDF11 and MSTN10,11,12,13. An important question that arose from these identifications was whether the divergence of GDF11 and MSTN occurred at the time of the emergence of vertebrates. To provide an explanation, a phylogenetic study was conducted in various invertebrate and vertebrate species, and importantly, the amphioxus (Branchiostoma belcheri)14, which is an invertebrate known to be the closest relative of the vertebrates, was included in the analysis (Fig. 1a and Table 1). Additionally, the amino acid sequences of the full-length protein, the propeptide with the signal peptide, and C-terminal peptide were separately compared (Fig. 1b−d). All phylogenetic trees demonstrated a clear separation between the GDF11 and MSTN clusters that appeared after the divergence of vertebrates from the amphioxus, confirming that the gene duplication event occurred at the time when vertebrates and invertebrates split (Fig. 1b−d). Notably, unlike the single isoform of the MSTN gene observed in mammals, two isoforms of the mstn gene have been detected in fish10. The reason for and functional significance of the divergence of the two mstn genes in fish remains to be clarified. Interestingly, many of the reported functions of the invertebrate MSTN/GDF11 protein are very different from the well-established suppressive role of vertebrate MSTN in the development of multiple tissues, and the broad expression pattern of the ancestral protein more closely resembles the expression pattern of vertebrate GDF11 11,13,15,16,17,18,19. These observations imply that MSTN most likely emerged from the ancestral gene to allow more specific control of skeletal muscle growth in vertebrates, although the relatively small amount of information available on the function of invertebrate MSTN/GDF11 limits further interpretation. The reported physiological roles of the ancestral protein in invertebrates will be discussed in more detail later.
Proteolytic processing of GDF11 and MSTN
Both GDF11 and MSTN, like the other members of the TGF-β family, are initially synthesized as precursor proteins and are subsequently cleaved by proteases to produce biologically active mature ligands. More specifically, following the removal of the signal peptides by signal peptidases, furin-like proteases recognize and cleave the conserved RSRR residues of GDF11 and MSTN, generating N-terminal propeptides and C-terminal mature peptides20. The different types of furin-like proprotein convertases and their substrates are listed in Table 2. The proprotein convertase PC5/6 was demonstrated to specifically cleave GDF11 by recognizing the RSRR↓N cleavage motif, which is not present in MSTN21. Accordingly, mice deficient in PC5/6 were shown to phenocopy Gdf11-null mice by exhibiting anterior homeotic transformations of the vertebrae, the lack of a tail, kidney agenesis, and retarded ossification21. After the cleavage of the RSRR site by a furin-like protease, the propeptide and mature peptide remain noncovalently associated with each other, forming a latent complex that is unable to bind receptors. However, a recent study showed that the latent MSTN complex can also become capable of binding receptors after being exposed to acidic conditions. Exposure to acidic conditions led to a conformational change of the latent MSTN complex and stimulated it to become in a triggered state, in which the pro- and mature domains still remain associated but were capable of signaling22. The fact that MSTN can exist in both fully latent and triggered states further demonstrates the complexity of its activation mechanism. Nonetheless, to achieve full signaling activity, both the latent GDF11 and MSTN complexes require additional cleavage of the N-terminal propeptides by BMP1/tolloid (TLD)-like metalloproteinases, which dissociate the propeptides from the mature C-terminal dimers, thus freeing the ligands for receptor binding (Table 3)20. Mature dimers can also be inhibited by the addition of propeptides both in vitro and in vivo23.
To examine the rates of the evolutionary changes of the residues of GDF11 and MSTN, we utilized a recently developed webtool, Aminode24, and analyzed the evolutionarily constrained regions (ECRs) of the proteins (Fig. 2a and Supplementary Table S1). As expected, the mature domains of GDF11, MSTN, activins, and TGF-βs were remarkably well-conserved among vertebrate species, displaying extremely low rates of amino acid substitution in most positions (Fig. 2a). Surprisingly, only GDF11 presented a striking degree of sequence conservation in the prodomain, emphasizing the functional significance of this region (Fig. 2a). In fact, while GDF11 and MSTN share 89% amino acid sequence identity in their mature domains, which differ by only 11 residues (Fig. 2b, c), their prodomains share only 48% amino acid sequence identity. This suggests the strong possibility that GDF11 prodomains may be associated with distinct and crucial extracellular regulatory mechanisms and biological functions that are not observed for the prodomains of MSTN, which warrants further investigation that may uncover significant differences that were previously unnoticed for the mature ligands.
Molecular mechanisms of GDF11 and MSTN signaling
The mature GDF11 and MSTN ligands first bind to activin type 2 receptors (ACVR2A or ACVR2B) and subsequently recruit type 1 receptors, activin receptor-like kinase 4 (ALK4) or ALK5 to form a heteromeric receptor complex to elicit downstream signaling via phosphorylation of SMAD2 and/or SMAD3 (Fig. 3)20. Both GDF11 and MSTN were recently revealed to be capable of also recruiting ALK7, while GDF11 signaled more potently than MSTN through this receptor25. Structural analysis also demonstrated that mature GDF11 and MSTN share identical type 2 receptor-binding residues but exhibit differences in the prehelix loop and wrist helix of the type 1 receptor-binding site20. Indeed, GDF11 was shown to signal more effectively and induce a greater SMAD3-dependent signal through all type 1 receptors than MSTN, and substitution of the residues in the wrist helix of the MSTN type 1 interface with those of GDF11 significantly enhanced the potency of MSTN by improving the stability of the interaction between the prehelix loop and wrist helix25. In addition to stimulating SMAD2/3 phosphorylation, recent studies described that GDF11 can strongly activate SMAD1/5/9 phosphorylation in endothelial cells and osteoblasts to promote their proliferation and differentiation, respectively26,27. GDF11 was shown to utilize ALK1 receptors to elicit signal transduction through SMAD1/5/9 phosphorylation, which was effectively suppressed by siRNA-mediated knockdown of GDF1127. Via another layer of complexity, GDF11 and MSTN may signal through noncanonical pathways by activating other non-SMAD proteins, such as p38 MAPK, ERK, and JNK20.
The activities of mature GDF11 and MSTN are tightly modulated by different extracellular binding proteins, including follistatin (FST), follistatin-like 3 (FSTL3/FLRG), growth and differentiation factor-associated serum protein 1 (GASP1), GASP2, latent TGF-β binding protein 3 (LTBP3), and decorin20. In contrast to the FST-like proteins that antagonize a variety of molecules of the TGF-β family, GASP1 and GASP2 more selectively inhibit mature GDF11 and MSTN28. While GASP1 was shown to more potently bind MSTN/GDF11 than GASP2 in vitro29, GASP2 was shown to more specifically regulate GDF11 based on the similarity of the embryonic expression patterns of Gasp2 and Gdf11 and the phenotype of Gasp2 knockout mice, which exhibited posterior homeotic transformations indicative of GDF11 overactivity30. Recently, Parente et al.31 demonstrated that transgenic mice ubiquitously overexpressing GASP1 and GASP2 present distinct phenotypes with contrasting expression patterns of Gdf11 and Mstn. The study illustrated that Mstn expression was significantly upregulated in GASP1-overexpressing mice, which showed an increase in low oxidative muscle fibers and impaired metabolic homeostasis, but only Gdf11 but not Mstn expression was significantly elevated in GASP2-overexpressing mice, which exhibited an increase in fast glycolytic muscle fibers without metabolic defects31. These results provide evidence that distinct extracellular regulatory mechanisms and endogenous functions are associated with GDF11 and MSTN.
Both GDF11 and MSTN circulate in the blood, and maternal deficiency of MSTN was shown to stimulate additional muscle growth in Mstn-knockout pups32, implying that GDF11 and MSTN may function as endocrine signaling molecules. However, our previous findings in mosaic mice in which Mstn was deleted exclusively in posteriorly located muscles highlighted the important paracrine function of MSTN in addition to its endocrine action in regulating muscle mass33. Furthermore, whether circulating GDF11 levels have physiological relevance was formerly questioned based on a result showing that the molar concentration of circulating GDF11 was approximately 500 times less than that of MSTN34. Because GDF11 and MSTN circulate mostly in inactive, latent forms35, their local activation patterns and localization of antagonists may largely contribute to distinct physiological effects of GDF11 and MSTN. Therefore, due to the complex modes of action of GDF11 and MSTN, considerable caution is required for the interpretation of the results of tissue-specific deletion of GDF11 or MSTN in conditional knockout mice.
Developmental functions of GDF11 and MSTN
Functions of MSTN/GDF11 in invertebrates
The physiological roles of ancestral MSTN/GDF11 in invertebrates, despite the availability of sequence information, are much less well known than those of GDF11 and MSTN in vertebrates. It should be noted that most of the invertebrate studies that utilized genetic mutations and RNA interference (RNAi) methods have provided evidence that ancestral Mstn/Gdf11 positively regulates the development of diverse tissues and functions similarly to vertebrate GDF11 rather than MSTN (Table 4). Ancestral Mstn/Gdf11 was also shown to exhibit a broad expression pattern, which is similar to that of vertebrate GDF11 but different from the muscle-specific expression pattern of vertebrate MSTN. For instance, C. elegans daf-7, a homolog of GDF11 and MSTN expressed in ASI neurons, has been shown to promote the reproductive growth and development of worms11,19,36. Accordingly, daf-7-mutant worms exhibited a slower growth rate and increased dauer entry11. Genetic mutations or RNAi-mediated knockdown of daf-7 also resulted in an increase in fat accumulation18, despite a reduction in the feeding rate, and declines in germ cell production and sperm motility37,38. However, there have been conflicting reports regarding the role of DAF-7 in the regulation of lifespan. While Shaw et al.39 reported that daf-7 mutants and wild-type worms treated with daf-7 RNAi exhibited an increased lifespan, Fletcher and Kim12 more recently demonstrated that DAF-7 promotes lifespan extension in response to dietary restriction and that age-dependent reduction in daf-7 expression impairs the sensitivity of aged worms to the effects of dietary restriction on lifespan.
The insect gene myo, which is a homolog of GDF11 and MSTN, is strongly expressed in muscle and glial cells and has been shown to promote neuronal development and remodeling13,40,41, prevent age-related muscular dysfunction16, and extend the lifespan in Drosophila16,42. Specifically, RNAi-mediated knockdown of myo in glia13 or muscle16 in Drosophila resulted in neuronal remodeling defects or exacerbated age-related climbing defects accompanied by premature death, respectively. Furthermore, a recent study suggested that Myo extends lifespan in flies by exerting protective functions in muscle homeostasis through regulating 26S proteasome function42. However, whether Myo regulates muscle mass in flies requires further investigation due to the existence of conflicting reports. As an illustration, while Demontis et al.16 showed no changes in muscle mass, body weight, and feeding behavior upon either muscle-specific Myo suppression or overexpression, Augustin et al.43 demonstrated that muscle-specific silencing of Myo increased larval weight and body-wall muscle size. More recently, Upadhyay et al.44 re-examined the same mutant flies and suggested that Myo deficiency did not result in larger muscles and that Myo is functionally distinct from vertebrate MSTN in terms of regulating muscle size. They also reported that Myo promotes imaginal disc growth in Drosophila44. Meanwhile, depletion of Myo through RNAi injection in third-instar cricket nymphs prevented the normal molting cycle and metamorphosis and led to reductions in nymph body size and weight, although the extended developmental period of the RNAi-treated nymphs eventually led them to exhibit a larger final insect size45. Injection of RNAi targeting myo into either fifth- or sixth-instar nymphs resulted in developmental arrest and death, highlighting the crucial role of Myo in promoting proper insect development45. Similar functions of Myo were also reported for cockroaches46.
In shrimp, the ancestral Mstn/Gdf11 gene is expressed in diverse tissues, including muscle, hepatopancreas, eyestalk, heart, gill, and stomach, with the highest expression detected in the heart17. Endogenous expression of Mstn/Gdf11 in shrimp muscle has been shown to peak immediately after molting, a period when significant growth occurs without restriction by a hard exoskeleton17. Interestingly, downregulation of the shrimp Mstn/Gdf11 gene by tail-muscle injection of sequence-specific dsRNA led to a significantly impaired growth rate (68% reduction in final shrimp mass)17, an effect opposite to that observed after suppression of MSTN in vertebrates. Likewise, a separate study on shrimp revealed that silencing of the Mstn/Gdf11 gene by tail-muscle injection of dsRNA significantly diminished growth and the survival rate15, indicating that ancestral MSTN/GDF11 in invertebrates is a positive regulator of growth and development, unlike vertebrate MSTN. Moreover, Zhuo et al.47 identified long (428 amino acids) and short (420 amino acids) forms of banana shrimp MSTN and FmMSTN, and the long form was positively correlated with a larger size in shrimp. Injection of dsRNA targeting FmMstn into these shrimp impaired their normal molting cycle but also resulted in the enlargement of the pleopod muscles47, which contradicts earlier findings. Further analysis and quantitation of the muscle fiber size in different muscle types are required to fully elucidate the effects of shrimp MSTN/GDF11 on controlling muscle development.
Functions of GDF11 and MSTN during vertebrate development
During the embryonic development of vertebrates, GDF11 and MSTN exhibit distinct expression patterns and functions. In mice, Mstn is initially expressed in the myotome compartment of somites at E9.5 and continues to be expressed in skeletal muscles to repress hyperplasia or increase the number of muscle fibers during development4. On the other hand, Gdf11 is predominantly expressed in the mouse tail bud at E9.5 and specifies the positional identity of the skeleton along the anterior-posterior axis9. Correspondingly, Gdf11-null mice exhibit anterior homeotic transformations of the vertebrae by displaying an increase in the number of thoracic and lumbar vertebrae and vertebrosternal ribs9,48. It should be noted that Gdf11 and Mstn double-mutants (Mstn−/−; Gdf11−/−) exhibited more extensive homeotic transformations of the axial skeleton than Gdf11-null mice, indicating that GDF11 and MSTN have some redundant functions related to the control of skeletal patterning49. GDF11 has also been shown to mediate proper craniofacial development, as Gdf11-null mice display high (60%) penetrance of cleft palate48,50. In further support of this role of GDF11, a recent study identified a family with orofacial clefting and vertebral/rib hypersegmentation harboring a dominant-negative missense mutation in GDF11, in which an arginine is substituted for a glutamine at the furin protease cleavage site (R298Q)51. Additional analysis confirmed that mutant GDF11 (R298Q) is not processed into the active form, indicating that this mutation is the underlying cause of the phenotypes observed in this family51. An earlier study reported that GDF11 also promotes tooth development and that electroporation-mediated transfer of the Gdf11 gene to the amputated pulp of canine teeth enhances reparative dentin formation52. Furthermore, our group recently demonstrated that GDF11, in contrast to MSTN, facilitates osteogenesis during embryonic development and showed that compared to that in newborn wild-type mice, bone mass is diminished in newborn Gdf11-null mice and enhanced in newborn Mstn-null mice26.
Multiple studies that utilized Gdf11-null embryos demonstrated that GDF11 plays a crucial role in the development of various organs. Specifically, analysis of Gdf11-null mice revealed that the majority of these mice experience complete renal agenesis and failure of ureteric bud outgrowth from the Wolffian duct53. These mice were further shown to exhibit malformations of the stomach characterized by a two-fold reduction in the thickness of the gastric wall and a decreased number of gastric rugae (epithelial folds), a smaller spleen, and an abnormally shaped pancreas54, implying that GDF11 is essential for proper morphogenesis of the foregut-derived organs. Gdf11 deficiency also resulted in the greater expansion of islet progenitor cells as well as the impairment of β-cell differentiation in the pancreas54. In the olfactory epithelium and retina, GDF11 was shown to inhibit neurogenesis by either repressing progenitor cell proliferation or altering progenitor cell fate55,56. This conclusion was supported by the significantly increased number of olfactory epithelium neurons and retinal ganglion cells in mice lacking GDF11 and the contrasting patterns observed in mice deficient in FST, an antagonist of GDF11. However, a delay in neuronal differentiation and gliogenesis was later reported in the spinal cord of Gdf11-null mice, suggesting that GDF11 promotes the temporal progression of neurogenesis in the developing spinal cord57. In addition, using chicken embryos, Gamer et al.58 demonstrated that implantation of beads soaked in human recombinant GDF11 protein into early wing buds led to a dramatic truncation of the limbs due to suppression of both myogenesis and chondrogenesis. In contrast, a recent analysis of Gdf11-null embryos at E15.5 and Gdf11-null sternal chondrocytes revealed that chondrocyte maturation was impaired under Gdf11-deficient conditions26. Moreover, skeletal muscle-specific deletion of Gdf11 using conditional knockout techniques resulted in no differences in muscle mass and fiber type, indicating that the functions of GDF11 and MSTN in the skeletal muscles are most likely divergent49. Additional investigation of the skeletal muscles of Gdf11-null embryos will further clarify the role of GDF11 in myogenesis during development.
Postnatal functions of GDF11 and MSTN in various tissues
MSTN in skeletal muscle
The primary function of MSTN became evident when mice homozygous for Mstn deletion were shown to have a substantial increase in skeletal muscle mass, with individual muscle groups growing to approximately twice the normal size4. A significant increase in muscle mass was also observed in humans, cattle, sheep, and dogs with naturally occurring mutations in the MSTN gene5,6,7,8. Further analysis of Mstn-null mice revealed that MSTN inhibits both skeletal muscle fiber hyperplasia during early development and hypertrophy in adults. The direct role of MSTN in postnatal suppression of muscle fiber hypertrophy was demonstrated by the severe loss of muscle mass induced by systemic overexpression of MSTN in adult mice35 and the increase in muscle mass in adult mice treated with a monoclonal anti-MSTN antibody59. Paradoxically, circulating MSTN levels were shown to decrease with age in humans, implying that this decline is likely a secondary effect of age-related muscle loss60.
Previous studies that applied recombinant MSTN proteins have presented mixed results regarding the role of MSTN in satellite cells. For instance, while several early studies showed that treatment with recombinant MSTN proteins inhibited C2C12 myoblast proliferation61,62, Rodgers et al.63 more recently argued that recombinant MSTN proteins stimulate C2C12 proliferation, emphasizing that the source of the recombinant MSTN protein can impact the outcome of an experiment. Furthermore, primary myoblasts isolated from both Mstn-null mouse embryos and adult mice were shown to exhibit a significantly increased proliferation rate64, and skeletal muscle regeneration after toxin-induced injury was significantly enhanced in Mstn-null mice65,66, indicating that endogenous MSTN suppresses satellite cell proliferation, differentiation, and muscle regeneration.
GDF11 in skeletal muscle
In contrast to Mstn-null mice, which survive to adulthood, Gdf11-null mice die shortly after birth, causing difficulties in identifying the role of GDF11 in adult tissue homeostasis. To overcome this limitation, Sinha et al.67 injected recombinant GDF11 proteins into aged mice and demonstrated that GDF11, in contrast to MSTN, acts as a rejuvenating factor in skeletal muscle. The aged mice treated with recombinant GDF11 proteins displayed striking improvements in muscle regeneration, exercise endurance, grip strength, myofibrillar and mitochondrial morphology, neuromuscular junctions, and the genomic integrity of muscle stem cells67. Furthermore, a more recent investigation in annual fish revealed that the application of GDF11 recombinant proteins boosted antioxidant enzyme activity in muscle, thus prolonging the lifespan68. Gdf11 expression levels were also shown to increase in slow-twitch muscles of aged mice after 6 weeks of treadmill running69. However, multiple studies have failed to reproduce these results, showing that GDF11 is deleterious towards muscle repair. For example, Egerman et al.70 argued that treatment with recombinant GDF11 proteins significantly impaired muscle regeneration and satellite cell expansion in mice through a downstream signaling pathway identical to that utilized by MSTN. Likewise, Hinken et al.71 showed that the recombinant GDF11 protein repressed satellite cell expansion, while Hammers et al.72 demonstrated that recombinant GDF11 and MSTN proteins decreased the myotube diameter through the canonical SMAD2/3 pathway. Zhou et al.73 also observed that injection of recombinant GDF11 protein into older rats significantly hindered muscle regeneration and function and induced tissue fibrosis. In addition, several other recent studies have shown that exogenous GDF11 treatment inhibits muscle growth74,75 and reduces strength76, while overexpression of the GDF11 propeptide, which antagonizes both mature GDF11 and MSTN, exerts beneficial effects23,77.
Although most reports strongly suggest that exogenous GDF11 supplementation exerts an inhibitory effect on skeletal muscle growth and regeneration, further studies that employ genetic loss-of-function approaches are needed to fully elucidate the endogenous function of GDF11 in skeletal muscles. Interestingly, Gdf11 expression levels were shown to peak in skeletal muscles in mice between 4 and 8 weeks of age, which is when the most dramatic postnatal muscle development occurs20. This expression pattern is similar to that observed in shrimp, in which the expression of Mstn/Gdf11, which was shown to promote growth unlike vertebrate MSTN, peaks immediately after molting17. Moreover, Gdf11 expression levels were revealed to increase even further in Mstn-null mice during periods of rapid muscle growth20. To date, only one study has applied conditional knockout techniques in mice to investigate the postnatal functions of GDF11 in regulating skeletal muscle mass49. The study demonstrated that skeletal muscle-specific targeting of Gdf11 had no significant effect on muscle mass, fiber number, or fiber type, demonstrating that GDF11 and MSTN exhibit distinct functions in controlling muscle size49. Additional examinations focusing on genetic approaches will further advance the understanding of the role of GDF11 in muscle biology.
MSTN in heart
Despite its establishment as a potent inhibitor of skeletal muscle growth, MSTN has also been implicated in the regulation of cardiac tissue growth and function. A recent study that analyzed hearts of adult Mstn-null mice revealed that the absence of MSTN had no effect on heart weight but significantly decreased the end systolic diameter and increased fractional shortening78. Lim et al.79 consecutively demonstrated that Mstn-null mice subjected to ligation of the left anterior descending artery to induce myocardial infarction (MI) exhibited accelerated recovery of the ejection fraction, reduced cardiac fibrosis, and lower mortality, indicating that MSTN negatively affects cardiac function. Likewise, senescent MSTN-deficient mice were shown to display improved fractional shortening, smaller left ventricular diastolic and systolic diameters, and decreased cardiac fibrosis80, although an earlier study reported that MSTN has no significant effect on cardiac hypertrophy or fibrosis81. Additionally, transgenic mice overexpressing MSTN in cardiomyocytes exhibited interstitial fibrosis and impaired cardiac function82. Surprisingly, tamoxifen-induced, cardiomyocyte-specific deletion of Mstn in adult mice was reported to provoke severe cardiac hypertrophy and heart failure83. The authors of the study assumed that the much greater severity of the cardiac phenotype observed in the conditional knockout mice than in the straight knockout mice was due to the distinct modes of compensation83. To clarify the function of MSTN in hearts and whether the cardiac phenotypes of MSTN deficiency are influenced by the enhancement of skeletal muscle mass, additional examinations are needed.
GDF11 in heart
In 2013, Loffredo et al.84 performed heterochronic parabiosis experiments in mice and identified GDF11 as a rejuvenating factor that circulates in plasma. The group utilized both proteomics (SOMAmer) and western blot analysis to determine that the circulating levels of GDF11 decline with age, reporting that restoration of youthful levels through daily intraperitoneal injections of recombinant GDF11 proteins reverses age-related cardiac hypertrophy84. Specifically, GDF11 rather than MSTN stimulated the dose-dependent inhibition of cardiac myocyte hypertrophy in vitro84. In further support of these results, Poggioli et al.85 showed that circulating GDF11/MSTN levels diminish with age in multiple mammalian species, and administration of recombinant GDF11 proteins dose-dependently decreased cardiac mass in both young and old mice after only 9 days. Likewise, Du et al.86 demonstrated that Gdf11 expression levels decline in aged hearts and that either targeted myocardial delivery of the Gdf11 gene or recombinant GDF11 protein enhanced cardiac function and effectively reduced infarct size after ischemic injury in aged mice, providing support for the anti-aging function of GDF11. The association of plasma GDF11/MSTN levels with cardiovascular outcomes and overall deaths in humans was also reported using SOMAmer technology, which revealed that in patients with stable ischemic heart disease, increased GDF11/MSTN levels were associated with decreased rates of cardiovascular events, left ventricular hypertrophy, and overall death87. Mechanistically, GDF11 was shown to increase intracellular calcium levels and activate SMAD2/3 to prevent cardiomyocyte hypertrophy88.
However, other groups have failed to observe the rejuvenating effects of GDF11 in cardiac tissues. After following the protocol used in a previous report84, Smith et al.89 showed that treatment of old mice with recombinant GDF11 proteins had no effect on cardiac mass, structure, or function. Moreover, recombinant GDF11 protein caused pathological hypertrophic signaling in neonatal rat ventricular myocytes, contradicting the classification of GDF11 as an anti-aging factor89. The same group subsequently published a dose-range study (0.5, 1.0, or 5.0 mg/kg) performed in young mice that underwent transverse aortic constriction (TAC) surgery and reported that although treatment with recombinant GDF11 proteins reduced pathological cardiac hypertrophy and fibrosis and improved cardiac function, the highest dose (5.0 mg/kg) led to severe cachexia and premature death, and they also issued a warning against the use of recombinant GDF11 proteins as a therapy90. Recombinant GDF11 protein treatment was also recently shown to increase the levels of reactive oxygen species in isoproterenol-treated H9C2 cells (rat heart-derived cardiomyoblast cell line)91 and impair cardiac function in old mice75. In addition, Egerman et al.70 pointed out that the SOMAmer and antibody used in the initial study by Loffredo et al.84 were nonspecific, claiming that circulating GDF11 levels actually increase with age and are a pro-aging factor. However, Poggioli et al.85 later proposed that the levels of GDF11 detected by Egerman et al.70 were in fact the levels of immunoglobulin light chain, generating further controversy regarding the circulating levels of GDF11. Applying a novel immunoplexed liquid chromatography with tandem mass spectrometry (LC-MS/MS) assay, Schafer et al.60 more accurately measured the circulating levels of GDF11 and reported that GDF11 levels remain constant in healthy adults throughout the lifespan. The study revealed that in older adults with severe aortic stenosis, higher GDF11 levels were associated with comorbidity and frailty60. Adding further controversy, a novel detection method using a parallel reaction monitoring (PRM) LC-MS/MS assay combined with immunoprecipitation recently showed that circulating levels of both GDF11 and MSTN significantly decline with age in female mice92.
In contrast to the large number of studies that investigated the effects of recombinant GDF11 proteins, only a single recent study has addressed the function of GDF11 based on cardiac-specific genetic deletion in mice. Using a Myh6-Cre transgene, Garbern et al.93 generated a conditional knockout mouse model in which Gdf11 was targeted exclusively to cardiomyocytes and demonstrated that the mice exhibited progressive left ventricular dilation and a decrease in left ventricular systolic function at the age of 6 months. However, the authors also noted the adverse effects of the Cre recombinase itself and the possible compensatory expression of Gdf11 in noncardiomyocytes, which prevented the clear interpretation of the mechanism underlying the above results93. Apparently, further genetic analysis with avoidance of Cre toxicity is required to delineate the endogenous role of GDF11 in cardiac tissues.
MSTN in the brain
Despite the scarcity of information on the function of MSTN in the brain, a recent study showed that Mstn is broadly expressed throughout the adult rat central nervous system, including most neurons, axons, oligodendrocytes, astrocytes, and ependymal cells, suggesting that MSTN may play a crucial role in the brain94. Regarding the role of MSTN in the nervous system, examination of adult Mstn-null mice revealed that these mice exhibit increases in the number and size of axons and a delay in their age-related reduction95. Furthermore, MSTN-deficient mice were shown to display enhanced myelin thickness in motor axons and an increase in the number of sensory axons96. These mice were also shown to present a smaller brain size than wild-type mice at the age of 4 months, but the mechanism of brain size regulation by MSTN remains unclear97. Meanwhile, conflicting reports exist regarding the effects of recombinant MSTN proteins on neuronal cells. For instance, while Kerrison et al.98 showed that recombinant MSTN proteins dose-dependently enhanced the survival of retinal ganglion cells and neurite outgrowth, others demonstrated that recombinant MSTN proteins decreased the formation of neuronal colonies56 or suggested that MSTN inhibits neurogenesis in the olfactory system99.
GDF11 in the brain
The perinatal lethality observed in Gdf11-deficient mice has led to multiple studies that investigated the effects of recombinant GDF11 proteins on adult neurogenesis, demonstrating that GDF11 is a pro-neurogenic and pro-angiogenic factor. Shortly after Loffredo et al.84 reported GDF11 as a rejuvenating agent that protects the aged heart, the same group proposed that GDF11 exerts anti-aging effects on the brain, which was supported by the improvement of the cerebral vasculature and the enhancement of neurogenesis after the treatment of old mice with recombinant GDF11 proteins100. A separate experiment also showed that systemic delivery of recombinant GDF11 proteins enhanced hippocampal neurogenesis and vasculature in old mice by acting on brain endothelial cells, and only GDF11 but not MSTN promoted VEGF secretion in brain endothelial cells101. Likewise, a single injection of recombinant GDF11 protein was shown to improve short-term visual memory in middle-aged mice through upregulation of SOX2 expression102. Furthermore, treatment with recombinant GDF11 proteins was shown to promote neurogenesis and angiogenesis in mouse and rat models of stroke103,104 and in a mouse model of Alzheimer’s disease, revealing GDF11 as a potential therapeutic option for neurodegenerative disorders105. In contrast, in vitro data on the effects of recombinant GDF11 protein exposure to neural stem cell lines demonstrated that GDF11 suppresses cell proliferation and migration, suggesting that GDF11 should be a target for pharmacological blockade106,107. While the majority of studies presented the beneficial effects of recombinant GDF11 treatment on the mature nervous system, additional analysis utilizing genetic knockdown or conditional knockout of Gdf11 will further advance the understanding of the role and action mechanism of endogenous GDF11 in the adult brain.
MSTN in bone
The deficiency of MSTN has been described to result in not only an enlargement in skeletal muscle mass but also an increase in bone mass. In this regard, Mstn-null mice were shown to exhibit enhanced bone mineral density in various parts of the skeleton26,80,108. In humans, genetic polymorphisms in MSTN were demonstrated to be associated with peak bone mineral density109. The effects of MSTN on bone may be both direct and indirect through the influence of skeletal muscle. While the indirect positive effect of enhanced skeletal muscle mass on bone strength was evidenced in Mstn-null mice110, the direct inhibition of osteoblast differentiation and stimulation of osteoclast formation by MSTN were also reported26,111,112,113,114. Surprisingly, despite the relatively low expression of Mstn in primary mouse osteoblasts and osteoclast precursors under physiological conditions, siRNA-mediated knockdown or genetic knockout of Mstn noticeably altered the differentiation rate of these cells26,113, highlighting the significant role of MSTN in the direct regulation of bone cells.
GDF11 in bone
As opposed to the consistent reports on the inhibitory function of MSTN on osteogenesis, the reports of the effects of GDF11 on adult bone homeostasis are controversial. In 2015, Zhang et al.115 demonstrated that circulating GDF11 levels were significantly diminished in both aged humans and patients with osteoporosis, and Gdf11 expression levels were substantially downregulated in the bone marrow of aged mice and mice with osteoporosis. Additionally, the group showed that treatment with recombinant GDF11 proteins significantly promoted osteoblast differentiation and inhibited adipogenesis of bone marrow mesenchymal stem cells115, emphasizing the pro-osteogenic role of GDF11, which is in contrast with the function of MSTN. However, Lu et al.116 subsequently published results showing the opposite results, indicating that recombinant GDF11 proteins inhibited osteoblast differentiation of bone marrow mesenchymal stem cells through a downstream signaling pathway identical to that of MSTN and that injection of recombinant GDF11 proteins suppressed bone formation in mice. In the same year, Liu et al.117 also reported similar findings and demonstrated that recombinant GDF11 treatment led to bone loss in both young and aged mice through impairment of osteoblast differentiation and increased osteoclast formation. Later, the same group further showed that recombinant GDF11 negatively affects bone healing in mice118,119. Moreover, in postmenopausal women, increased levels of circulating GDF11 were associated with decreased bone mineral density, demonstrating the inhibitory effect of GDF11 on bone formation120.
In an attempt to avoid the controversy surrounding the effects of recombinant GDF11 proteins, our group has recently applied conditional knockout strategies in mice to examine the endogenous function of GDF11 in osteogenesis26. Our findings revealed that both time-specific ubiquitous deletion and limb mesenchyme-specific deletion of Gdf11 resulted in diminished bone mass in young adult mice, suggesting that GDF11 endogenously promotes bone development, in contrast to MSTN26. Furthermore, both Gdf11-null osteoblasts and wild-type osteoblasts subjected to siRNA-mediated Gdf11 knockdown exhibited impaired differentiation and mineralization, while the opposite effects were observed in wild-type osteoblasts transfected with full-length GDF11 cDNA26. Whether there is a difference in the cellular and physiological outcomes of treatment with the full-length cDNA and mature forms of the GDF11 protein requires further investigation. A previous study demonstrated that skeleton-specific transgenic overexpression of the GDF11 propeptide, which is capable of inhibiting both mature forms of GDF11 and MSTN, enhanced bone formation in mice during embryogenesis and postnatal development121. However, these mice were shown to exhibit a posterior homeotic transformation in the cervical vertebra, resulting in transformation of the seventh cervical vertebra into a thoracic vertebra, which is the exact opposite of the anterior homeotic transformations observed in Gdf11-null mice9,48. Furthermore, the authors did not provide information on the relative expression of endogenous Gdf11 and the transgene during developmental stages, limiting the potential for the clear interpretation of the results122. Additional examination focused on genetic studies in mice will lead to additional insights into the endogenous mechanism of action of GDF11 in postnatal bone remodeling.
Therapeutic implications of GDF11 activation
Recombinant GDF11 protein as a therapeutic option
After the initial reports of GDF11 as a rejuvenating agent for the heart, skeletal muscle, and brain, numerous groups have evaluated the effects of recombinant GDF11 protein administration on various tissues (Table 5). However, despite using similar treatment and dosage regimens, multiple groups have produced widely varying results, especially in skeletal muscle and heart. Regarding this issue, Poggioli et al.85 pointed out the existence of batch-to-batch variations in the concentrations of recombinant GDF11 proteins, which was also confirmed by the manufacturer, and suggested that differences in protein sources, protein refolding efficiencies, and protein concentrations all possibly contributed to the disparity in the outcomes. Likewise, Rodgers and Eldridge34 highlighted the possible significant influence of the source and quality of recombinant proteins on experimental results and indicated that both Sinha et al.67 and Egerman et al.70, who reported opposing results, utilized bacterially generated recombinant proteins that may be less effective or even produce different effects depending on the folding status. In support of this claim, Rodgers et al.63 demonstrated that recombinant MSTN proteins produced in bacteria and eukaryotes behave differently in the regulation of C2C12 myoblast proliferation. Most importantly, even though differences in the type 1 receptor-binding residues and signaling potency between mature GDF11 and MSTN have been reported25, it is difficult to rule out the fact that recombinant GDF11 and MSTN proteins cannot be effectively distinguished due to their high sequence similarity, revealing the possibility that the responses mediated by recombinant GDF11 protein treatment actually reflect the endogenous functions of MSTN. Apparently, due to the large discrepancy in the reported effects of recombinant GDF11 protein treatment, further establishment of experimental settings that generate more reliable outcomes as well as different strategies for GDF11 supplementation will be needed for further consideration of GDF11 as a therapeutic option.
Potential adverse effects of targeting GDF11
Ample studies that noted the detrimental effects of recombinant GDF11 protein injection have also indicated GDF11 as a potential target for pharmacological blockade. However, the relatively little information is available on the endogenous functions of GDF11 in regulating adult physiology, which indicates the need for a cautious approach in the development of GDF11 inhibitors. In fact, sotatercept (ACE-011), an ACVR2A fusion protein originally designed by Acceleron Pharma to increase bone mineral density123, unexpectedly promoted rapid increases in hematocrit, hemoglobin, red blood cells, and late-stage erythropoiesis, which were suggested to be caused by suppression of endogenous GDF11124, although recent studies using conditional knockout techniques refuted this mechanism125,126. In addition, our group has recently demonstrated that transgenic overexpression of FST, an endogenous inhibitor of MSTN, GDF11, and activins, substantially enhanced muscle mass but induced spontaneous tibial fractures due to a reduction in bone mineral density, implying that inhibition of GDF11 may have adverse effects on bone26. Therefore, possible side effects triggered by both exogenous administration and endogenous inhibition of GDF11 and the means to resolve them should be evaluated with caution in order to enhance the potential for GDF11 to be applied in clinical settings.
Conclusion and future perspectives
The remarkable sequence similarity between GDF11 and MSTN led to the assumption that the two molecules are functionally redundant. However, multiple genetic studies in mice provide clear evidence that they play distinct roles under a range of physiological conditions. Notably, the perinatal lethality observed in Gdf11-null mice, in contrast to the long-term viability of MSTN-deficient mice, led to complications in characterizing the role of GDF11 in adult tissues and caused many groups to utilize recombinant GDF11 proteins to identify its postnatal function. However, difficulties in biochemically distinguishing between the recombinant GDF11 and MSTN proteins as well as variations in the quality of recombinant proteins aroused much controversy regarding the effects of GDF11 treatment. Indeed, while numerous studies have presented the beneficial physiological outcomes after supplementation with recombinant GDF11 proteins, providing a rationale for its therapeutic application, an equally large number of studies have also underscored its harmfulness, demonstrating GDF11 as a potential therapeutic target for inhibition. Therefore, future studies should focus on implementing genetic knockdown or conditional knockout techniques, which may be more promising approaches to differentiate the endogenous functions of GDF11 and MSTN and their regulatory mechanisms. Furthermore, reliable research strategies to improve the consistency of test results are needed to support the progression of GDF11 therapy or GDF11 inhibitors to clinical trials.
Morikawa, M., Derynck, R. & Miyazono, K. TGF-beta and the TGF-beta family: context-dependent roles in cell and tissue physiology. Cold Spring Harb. Perspect. Biol. 8, a021873 (2016).
Nakashima, M., Toyono, T., Akamine, A. & Joyner, A. Expression of growth/differentiation factor 11, a new member of the BMP/TGFbeta superfamily during mouse embryogenesis. Mech. Dev. 80, 185–189 (1999).
Gamer, L. W. et al. A novel BMP expressed in developing mouse limb, spinal cord, and tail bud is a potent mesoderm inducer in Xenopus embryos. Dev. Biol. 208, 222–232 (1999).
McPherron, A. C., Lawler, A. M. & Lee, S. J. Regulation of skeletal muscle mass in mice by a new TGF-beta superfamily member. Nature 387, 83–90 (1997).
Mosher, D. S. et al. A mutation in the myostatin gene increases muscle mass and enhances racing performance in heterozygote dogs. PLoS Genet. 3, e79 (2007).
Clop, A. et al. A mutation creating a potential illegitimate microRNA target site in the myostatin gene affects muscularity in sheep. Nat. Genet. 38, 813–818 (2006).
Schuelke, M. et al. Myostatin mutation associated with gross muscle hypertrophy in a child. N. Engl. J. Med. 350, 2682–2688 (2004).
McPherron, A. C. & Lee, S. J. Double muscling in cattle due to mutations in the myostatin gene. Proc. Natl Acad. Sci. USA 94, 12457–12461 (1997).
McPherron, A. C., Lawler, A. M. & Lee, S. J. Regulation of anterior/posterior patterning of the axial skeleton by growth/differentiation factor 11. Nat. Genet. 22, 260–264 (1999).
Funkenstein, B. & Olekh, E. Growth/differentiation factor-11: an evolutionary conserved growth factor in vertebrates. Dev. Genes Evol. 220, 129–137 (2010).
Nagata, A. et al. The evolutionarily conserved deubiquitinase UBH1/UCH-L1 augments DAF7/TGF-beta signaling, inhibits dauer larva formation, and enhances lung tumorigenesis. J. Biol. Chem. 295, 9105–9120 (2020).
Fletcher, M. & Kim, D. H. Age-dependent neuroendocrine signaling from sensory neurons modulates the effect of dietary restriction on longevity of Caenorhabditis elegans. PLoS Genet. 13, e1006544 (2017).
Awasaki, T., Huang, Y., O’Connor, M. B. & Lee, T. Glia instruct developmental neuronal remodeling through TGF-beta signaling. Nat. Neurosci. 14, 821–823 (2011).
Xing, F. et al. Characterization of amphioxus GDF8/11 gene, an archetype of vertebrate MSTN and GDF11. Dev. Genes Evol. 217, 549–554 (2007).
Lee, J. H. et al. Effective RNA-silencing strategy of Lv-MSTN/GDF11 gene and its effects on the growth in shrimp, Litopenaeus vannamei. Comp. Biochem. Physiol. B Biochem. Mol. Biol. 179, 9–16 (2015).
Demontis, F., Patel, V. K., Swindell, W. R. & Perrimon, N. Intertissue control of the nucleolus via a myokine-dependent longevity pathway. Cell Rep. 7, 1481–1494 (2014).
De Santis, C. et al. Growing backwards: an inverted role for the shrimp ortholog of vertebrate myostatin and GDF11. J. Exp. Biol. 214, 2671–2677 (2011).
Greer, E. R., Perez, C. L., Van Gilst, M. R., Lee, B. H. & Ashrafi, K. Neural and molecular dissection of a C. elegans sensory circuit that regulates fat and feeding. Cell Metab. 8, 118–131 (2008).
Gunther, C. V., Georgi, L. L. & Riddle, D. L. A Caenorhabditis elegans type I TGF beta receptor can function in the absence of type II kinase to promote larval development. Development 127, 3337–3347 (2000).
Walker, R. G. et al. Biochemistry and biology of GDF11 and myostatin: similarities, differences, and questions for future investigation. Circ. Res. 118, 1125–1141 (2016). discussion 1142.
Essalmani, R. et al. In vivo functions of the proprotein convertase PC5/6 during mouse development: Gdf11 is a likely substrate. Proc. Natl Acad. Sci. USA 105, 5750–5755 (2008).
Walker, R. G. et al. Molecular characterization of latent GDF8 reveals mechanisms of activation. Proc. Natl Acad. Sci. USA 115, E866–E875 (2018).
Jin, Q. et al. A GDF11/myostatin inhibitor, GDF11 propeptide-Fc, increases skeletal muscle mass and improves muscle strength in dystrophic mdx mice. Skelet. Muscle 9, 16 (2019).
Chang, K. T., Guo, J., di Ronza, A. & Sardiello, M. Aminode: identification of evolutionary constraints in the human proteome. Sci. Rep. 8, 1357 (2018).
Walker, R. G. et al. Structural basis for potency differences between GDF8 and GDF11. BMC Biol. 15, 19 (2017).
Suh, J. et al. GDF11 promotes osteogenesis as opposed to MSTN, and follistatin, a MSTN/GDF11 inhibitor, increases muscle mass but weakens bone. Proc. Natl Acad. Sci. USA 117, 4910–4920 (2020).
Yu, X. et al. Growth differentiation factor 11 promotes abnormal proliferation and angiogenesis of pulmonary artery endothelial cells. Hypertension 71, 729–741 (2018).
Kondas, K., Szlama, G., Trexler, M. & Patthy, L. Both WFIKKN1 and WFIKKN2 have high affinity for growth and differentiation factors 8 and 11. J. Biol. Chem. 283, 23677–23684 (2008).
Walker, R. G. et al. Alternative binding modes identified for growth and differentiation factor-associated serum protein (GASP) family antagonism of myostatin. J. Biol. Chem. 290, 7506–7516 (2015).
Lee, Y. S. & Lee, S. J. Regulation of GDF-11 and myostatin activity by GASP-1 and GASP-2. Proc. Natl Acad. Sci. USA 110, E3713–E3722 (2013).
Parente, A. et al. GASP-2 overexpressing mice exhibit a hypermuscular phenotype with contrasting molecular effects compared to GASP-1 transgenics. FASEB J. 34, 4026–4040 (2020).
Lee, S. J. Quadrupling muscle mass in mice by targeting TGF-beta signaling pathways. PLoS ONE 2, e789 (2007).
Lee, Y. S., Huynh, T. V. & Lee, S. J. Paracrine and endocrine modes of myostatin action. J. Appl. Physiol. 120, 592–598 (2016).
Rodgers, B. D. & Eldridge, J. A. Reduced circulating GDF11 is unlikely responsible for age-dependent changes in mouse heart, muscle, and brain. Endocrinology 156, 3885–3888 (2015).
Zimmers, T. A. et al. Induction of cachexia in mice by systemically administered myostatin. Science 296, 1486–1488 (2002).
Ren, P. et al. Control of C. elegans larval development by neuronal expression of a TGF-beta homolog. Science 274, 1389–1391 (1996).
McKnight, K. et al. Neurosensory perception of environmental cues modulates sperm motility critical for fertilization. Science 344, 754–757 (2014).
Dalfo, D., Michaelson, D. & Hubbard, E. J. Sensory regulation of the C. elegans germline through TGF-beta-dependent signaling in the niche. Curr. Biol. 22, 712–719 (2012).
Shaw, W. M., Luo, S., Landis, J., Ashraf, J. & Murphy, C. T. The C. elegans TGF-beta Dauer pathway regulates longevity via insulin signaling. Curr. Biol. 17, 1635–1645 (2007).
Lee-Hoeflich, S. T., Zhao, X., Mehra, A. & Attisano, L. The Drosophila type II receptor, Wishful thinking, binds BMP and myoglianin to activate multiple TGFbeta family signaling pathways. FEBS Lett. 579, 4615–4621 (2005).
Aberle, H. et al. Wishful thinking encodes a BMP type II receptor that regulates synaptic growth in Drosophila. Neuron 33, 545–558 (2002).
Langerak, S. et al. The Drosophila TGF-beta/Activin-like ligands Dawdle and Myoglianin appear to modulate adult lifespan through regulation of 26S proteasome function in adult muscle. Biol. Open 7, bio029454 (2018).
Augustin, H. et al. Myostatin-like proteins regulate synaptic function and neuronal morphology. Development 144, 2445–2455 (2017).
Upadhyay, A., Peterson, A. J., Kim, M. J. & O'Connor, M. B. Muscle-derived Myoglianin regulates Drosophila imaginal disc growth. Elife 9, e51710 (2020).
Ishimaru, Y. et al. TGF-beta signaling in insects regulates metamorphosis via juvenile hormone biosynthesis. Proc. Natl Acad. Sci. USA 113, 5634–5639 (2016).
Kamsoi, O. & Belles, X. Myoglianin triggers the premetamorphosis stage in hemimetabolan insects. FASEB J. 33, 3659–3669 (2019).
Zhuo, R. Q., Zhou, T. T., Yang, S. P. & Chan, S. F. Characterization of a molt-related myostatin gene (FmMstn) from the banana shrimp Fenneropenaeus merguiensis. Gen. Comp. Endocrinol. 248, 55–68 (2017).
Suh, J. et al. Growth differentiation factor 11 locally controls anterior-posterior patterning of the axial skeleton. J. Cell. Physiol. 234, 23360–23368 (2019).
McPherron, A. C., Huynh, T. V. & Lee, S. J. Redundancy of myostatin and growth/differentiation factor 11 function. BMC Dev. Biol. 9, 24 (2009).
Lee, Y. S. & Lee, S. J. Roles of GASP-1 and GDF-11 in dental and craniofacial development. J. Oral Med. Pain 40, 110–114 (2015).
Cox, T. C. et al. Mutations in GDF11 and the extracellular antagonist, Follistatin, as a likely cause of Mendelian forms of orofacial clefting in humans. Hum. Mutat. 40, 1813–1825 (2019).
Nakashima, M., Mizunuma, K., Murakami, T. & Akamine, A. Induction of dental pulp stem cell differentiation into odontoblasts by electroporation-mediated gene delivery of growth/differentiation factor 11 (Gdf11). Gene Ther. 9, 814–818 (2002).
Esquela, A. F. & Lee, S. J. Regulation of metanephric kidney development by growth/differentiation factor 11. Dev. Biol. 257, 356–370 (2003).
Harmon, E. B. et al. GDF11 modulates NGN3+ islet progenitor cell number and promotes beta-cell differentiation in pancreas development. Development 131, 6163–6174 (2004).
Kim, J. et al. GDF11 controls the timing of progenitor cell competence in developing retina. Science 308, 1927–1930 (2005).
Wu, H. H. et al. Autoregulation of neurogenesis by GDF11. Neuron 37, 197–207 (2003).
Shi, Y. & Liu, J. P. Gdf11 facilitates temporal progression of neurogenesis in the developing spinal cord. J. Neurosci. 31, 883–893 (2011).
Gamer, L. W., Cox, K. A., Small, C. & Rosen, V. Gdf11 is a negative regulator of chondrogenesis and myogenesis in the developing chick limb. Dev. Biol. 229, 407–420 (2001).
Whittemore, L. A. et al. Inhibition of myostatin in adult mice increases skeletal muscle mass and strength. Biochem. Biophys. Res. Commun. 300, 965–971 (2003).
Schafer, M. J. et al. Quantification of GDF11 and myostatin in human aging and cardiovascular disease. Cell Metab. 23, 1207–1215 (2016).
Taylor, W. E. et al. Myostatin inhibits cell proliferation and protein synthesis in C2C12 muscle cells. Am. J. Physiol. Endocrinol. Metab. 280, E221–E228 (2001).
Thomas, M. et al. Myostatin, a negative regulator of muscle growth, functions by inhibiting myoblast proliferation. J. Biol. Chem. 275, 40235–40243 (2000).
Rodgers, B. D. et al. Myostatin stimulates, not inihibits, C2C12 myoblast proliferation. Endocrinology 155, 670–675 (2014).
McCroskery, S., Thomas, M., Maxwell, L., Sharma, M. & Kambadur, R. Myostatin negatively regulates satellite cell activation and self-renewal. J. Cell Biol. 162, 1135–1147 (2003).
Wagner, K. R., Liu, X., Chang, X. & Allen, R. E. Muscle regeneration in the prolonged absence of myostatin. Proc. Natl Acad. Sci. USA 102, 2519–2524 (2005).
McCroskery, S. et al. Improved muscle healing through enhanced regeneration and reduced fibrosis in myostatin-null mice. J. Cell Sci. 118, 3531–3541 (2005).
Sinha, M. et al. Restoring systemic GDF11 levels reverses age-related dysfunction in mouse skeletal muscle. Science 344, 649–652 (2014).
Zhou, Y. et al. Late-onset administration of GDF11 extends life span and delays development of age-related markers in the annual fish Nothobranchius guentheri. Biogerontology 20, 225–239 (2019).
Lee, M., Oikawa, S., Ushida, T., Suzuki, K. & Akimoto, T. Effects of exercise training on growth and differentiation factor 11 expression in aged mice. Front. Physiol. 10, 970 (2019).
Egerman, M. A. et al. GDF11 increases with age and inhibits skeletal muscle regeneration. Cell Metab. 22, 164–174 (2015).
Hinken, A. C. et al. Lack of evidence for GDF11 as a rejuvenator of aged skeletal muscle satellite cells. Aging Cell 15, 582–584 (2016).
Hammers, D. W. et al. Supraphysiological levels of GDF11 induce striated muscle atrophy. EMBO Mol. Med. 9, 531–544 (2017).
Zhou, Y. et al. GDF11 treatment attenuates the recovery of skeletal muscle function after injury in older rats. AAPS J. 19, 431–437 (2017).
Jones, J. E. et al. Supraphysiologic administration of GDF11 induces cachexia in part by upregulating GDF15. Cell Rep. 22, 3375 (2018).
Roh, J. D. et al. Activin type II receptor signaling in cardiac aging and heart failure. Sci. Transl. Med. 11, eaau8680 (2019).
Zimmers, T. A. et al. Exogenous GDF11 induces cardiac and skeletal muscle dysfunction and wasting. Basic Res. Cardiol. 112, 48 (2017).
Jin, Q., Qiao, C., Li, J., Li, J. & Xiao, X. Neonatal systemic AAV-mediated gene delivery of GDF11 inhibits skeletal muscle growth. Mol. Ther. 26, 1109–1117 (2018).
Butcher, J. T. et al. Effect of myostatin deletion on cardiac and microvascular function. Physiol. Rep. 5, e13525 (2017).
Lim, S. et al. Absence of myostatin improves cardiac function following myocardial infarction. Heart Lung Circ. 27, 693–701 (2018).
Morissette, M. R. et al. Effects of myostatin deletion in aging mice. Aging Cell 8, 573–583 (2009).
Cohn, R. D., Liang, H. Y., Shetty, R., Abraham, T. & Wagner, K. R. Myostatin does not regulate cardiac hypertrophy or fibrosis. Neuromuscul. Disord. 17, 290–296 (2007).
Biesemann, N. et al. Myostatin induces interstitial fibrosis in the heart via TAK1 and p38. Cell Tissue Res. 361, 779–787 (2015).
Biesemann, N. et al. Myostatin regulates energy homeostasis in the heart and prevents heart failure. Circ. Res. 115, 296–310 (2014).
Loffredo, F. S. et al. Growth differentiation factor 11 is a circulating factor that reverses age-related cardiac hypertrophy. Cell 153, 828–839 (2013).
Poggioli, T. et al. Circulating growth differentiation factor 11/8 levels decline with age. Circ. Res. 118, 29–37 (2016).
Du, G. Q. et al. Targeted myocardial delivery of GDF11 gene rejuvenates the aged mouse heart and enhances myocardial regeneration after ischemia-reperfusion injury. Basic Res. Cardiol. 112, 7 (2017).
Olson, K. A. et al. Association of growth differentiation factor 11/8, putative anti-ageing factor, with cardiovascular outcomes and overall mortality in humans: analysis of the Heart and Soul and HUNT3 cohorts. Eur. Heart J. 36, 3426–3434 (2015).
Duran, J. et al. GDF11 modulates Ca(2+)-dependent Smad2/3 signaling to prevent cardiomyocyte hypertrophy. Int. J. Mol. Sci. 19, 1508 (2018).
Smith, S. C. et al. GDF11 does not rescue aging-related pathological hypertrophy. Circ. Res. 117, 926–932 (2015).
Harper, S. C. et al. GDF11 decreases pressure overload-induced hypertrophy, but can cause severe cachexia and premature death. Circ. Res. 123, 1220–1231 (2018).
Zhang, X. J. et al. Growth differentiation factor 11 is involved in isoproterenolinduced heart failure. Mol. Med. Rep. 19, 4109–4118 (2019).
Camparini, L. et al. Targeted approach to distinguish and determine absolute levels of GDF8 and GDF11 in mouse serum. Proteomics 20, e1900104 (2020).
Garbern, J. et al. Analysis of Cre-mediated genetic deletion of Gdf11 in cardiomyocytes of young mice. Am. J. Physiol. Heart Circ. Physiol. 317, H201–H212 (2019).
Hayashi, Y. et al. Myostatin expression in the adult rat central nervous system. J. Chem. Neuroanat. 94, 125–138 (2018).
Elashry, M. I. et al. Axon and muscle spindle hyperplasia in the myostatin null mouse. J. Anat. 218, 173–184 (2011).
Jones, M. R., Villalon, E., Northcutt, A. J., Calcutt, N. A. & Garcia, M. L. Differential effects of myostatin deficiency on motor and sensory axons. Muscle Nerve 56, E100–E107 (2017).
Jeffery, N. & Mendias, C. Endocranial and masticatory muscle volumes in myostatin-deficient mice. R. Soc. Open Sci. 1, 140187 (2014).
Kerrison, J. B., Lewis, R. N., Otteson, D. C. & Zack, D. J. Bone morphogenetic proteins promote neurite outgrowth in retinal ganglion cells. Mol. Vis. 11, 208–215 (2005).
Iwasaki, S. et al. Expression of myostatin in neural cells of the olfactory system. Mol. Neurobiol. 47, 1–8 (2013).
Katsimpardi, L. et al. Vascular and neurogenic rejuvenation of the aging mouse brain by young systemic factors. Science 344, 630–634 (2014).
Ozek, C., Krolewski, R. C., Buchanan, S. M. & Rubin, L. L. Growth differentiation factor 11 treatment leads to neuronal and vascular improvements in the hippocampus of aged mice. Sci. Rep. 8, 17293 (2018).
Zhang, M., Jadavji, N. M., Yoo, H. S. & Smith, P. D. Recombinant growth differentiation factor 11 influences short-term memory and enhances Sox2 expression in middle-aged mice. Behav. Brain Res. 341, 45–49 (2018).
Ma, J. et al. Growth differentiation factor 11 improves neurobehavioral recovery and stimulates angiogenesis in rats subjected to cerebral ischemia/reperfusion. Brain Res. Bull. 139, 38–47 (2018).
Lu, L. et al. Growth differentiation factor 11 promotes neurovascular recovery after stroke in mice. Front. Cell. Neurosci. 12, 205 (2018).
Zhang, W. et al. GDF11 rejuvenates cerebrovascular structure and function in an animal model of Alzheimer’s disease. J. Alzheimers Dis. 62, 807–819 (2018).
Wang, Z. et al. GDF11 induces differentiation and apoptosis and inhibits migration of C17.2 neural stem cells via modulating MAPK signaling pathway. PeerJ 6, e5524 (2018).
Williams, G. et al. Transcriptional basis for the inhibition of neural stem cell proliferation and migration by the TGFbeta-family member GDF11. PLoS ONE 8, e78478 (2013).
Hamrick, M. W. Increased bone mineral density in the femora of GDF8 knockout mice. Anat. Rec. A Discov. Mol. Cell Evol. Biol. 272, 388–391 (2003).
Zhang, Z. L. et al. Association between myostatin gene polymorphisms and peak BMD variation in Chinese nuclear families. Osteoporos. Int. 19, 39–47 (2008).
Hamrick, M. W., Samaddar, T., Pennington, C. & McCormick, J. Increased muscle mass with myostatin deficiency improves gains in bone strength with exercise. J. Bone Miner. Res. 21, 477–483 (2006).
Qin, Y. W. et al. Myostatin inhibits osteoblastic differentiation by suppressing osteocyte-derived exosomal microRNA-218: a novel mechanism in muscle-bone communication. J. Biol. Chem. 292, 11021–11033 (2017).
Chen, Y. S. et al. GDF8 inhibits bone formation and promotes bone resorption in mice. Clin. Exp. Pharmacol. Physiol. 44, 500–508 (2017).
Dankbar, B. et al. Myostatin is a direct regulator of osteoclast differentiation and its inhibition reduces inflammatory joint destruction in mice. Nat. Med. 21, 1085–1090 (2015).
Hamrick, M. W. et al. Loss of myostatin (GDF8) function increases osteogenic differentiation of bone marrow-derived mesenchymal stem cells but the osteogenic effect is ablated with unloading. Bone 40, 1544–1553 (2007).
Zhang, Y. et al. Growth differentiation factor 11 is a protective factor for osteoblastogenesis by targeting PPARgamma. Gene 557, 209–214 (2015).
Lu, Q. et al. GDF11 inhibits bone formation by activating Smad2/3 in bone marrow mesenchymal stem cells. Calcif. Tissue Int. 99, 500–509 (2016).
Liu, W. et al. GDF11 decreases bone mass by stimulating osteoclastogenesis and inhibiting osteoblast differentiation. Nat. Commun. 7, 12794 (2016).
Liu, W., Zhou, L., Xue, H., Li, H. & Yuan, Q. Growth differentiation factor 11 impairs titanium implant healing in the femur and leads to mandibular bone loss. J. Periodontol. 91, 1203–1212 (2020).
Zheng, R. et al. Recombinant growth differentiation factor 11 impairs fracture healing through inhibiting chondrocyte differentiation. Ann. N. Y. Acad. Sci. 1440, 54–66 (2019).
Chen, Y. et al. Relationship of serum GDF11 levels with bone mineral density and bone turnover markers in postmenopausal Chinese women. Bone Res. 4, 16012 (2016).
Li, Z. et al. Transgenic overexpression of bone morphogenetic protein 11 propeptide in skeleton enhances bone formation. Biochem. Biophys. Res. Commun. 416, 289–292 (2011).
Li, Z., Kawasumi, M., Zhao, B., Moisyadi, S. & Yang, J. Transgenic over-expression of growth differentiation factor 11 propeptide in skeleton results in transformation of the seventh cervical vertebra into a thoracic vertebra. Mol. Reprod. Dev. 77, 990–997 (2010).
Sherman, M. L. et al. Multiple-dose, safety, pharmacokinetic, and pharmacodynamic study of sotatercept (ActRIIA-IgG1), a novel erythropoietic agent, in healthy postmenopausal women. J. Clin. Pharmacol. 53, 1121–1130 (2013).
Dussiot, M. et al. An activin receptor IIA ligand trap corrects ineffective erythropoiesis in beta-thalassemia. Nat. Med. 20, 398–407 (2014).
Guerra, A. et al. Lack of Gdf11 does not improve anemia or prevent the activity of RAP-536 in a mouse model of beta-thalassemia. Blood 134, 568–572 (2019).
Goldstein, J. M. et al. Steady-state and regenerative hematopoiesis occurs normally in mice in the absence of GDF11. Blood 134, 1712–1716 (2019).
Kumar, S., Stecher, G., Li, M., Knyaz, C. & Tamura, K. MEGA X: molecular evolutionary genetics analysis across computing platforms. Mol. Biol. Evol. 35, 1547–1549 (2018).
Edgar, R. C. MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Res. 32, 1792–1797 (2004).
Yung, L. M. et al. ACTRIIA-Fc rebalances activin/GDF versus BMP signaling in pulmonary hypertension. Sci. Transl. Med. 12, eaaz5660 (2020).
Zhang, Y. H. et al. GDF11/BMP11 activates both smad1/5/8 and smad2/3 signals but shows no significant effect on proliferation and migration of human umbilical vein endothelial cells. Oncotarget 7, 12063–12074 (2016).
Jean, F. et al. Enzymic characterization of murine and human prohormone convertase-1 (mPC1 and hPC1) expressed in mammalian GH4C1 cells. Biochem. J. 292(Pt 3), 891–900 (1993).
Seidah, N. G. & Prat, A. The biology and therapeutic targeting of the proprotein convertases. Nat. Rev. Drug Discov. 11, 367–383 (2012).
Shennan, K. I., Taylor, N. A., Jermany, J. L., Matthews, G. & Docherty, K. Differences in pH optima and calcium requirements for maturation of the prohormone convertases PC2 and PC3 indicates different intracellular locations for these events. J. Biol. Chem. 270, 1402–1407 (1995).
Constam, D. B. Regulation of TGFbeta and related signals by precursor processing. Semin. Cell Dev. Biol. 32, 85–97 (2014).
Basak, A. et al. Enzymic characterization in vitro of recombinant proprotein convertase PC4. Biochem. J. 343(Pt 1), 29–37 (1999).
Tsuji, A. et al. Inactivation of proprotein convertase, PACE4, by alpha1-antitrypsin Portland (alpha1-PDX), a blocker of proteolytic activation of bone morphogenetic protein during embryogenesis: evidence that PACE4 is able to form an SDS-stable acyl intermediate with alpha1-PDX. J. Biochem. 126, 591–603 (1999).
Munzer, J. S. et al. In vitro characterization of the novel proprotein convertase PC7. J. Biol. Chem. 272, 19672–19681 (1997).
Wetsel, W. C. et al. Disruption of the expression of the proprotein convertase PC7 reduces BDNF production and affects learning and memory in mice. Proc. Natl Acad. Sci. USA 110, 17362–17367 (2013).
Toure, B. B. et al. Biosynthesis and enzymatic characterization of human SKI-1/S1P and the processing of its inhibitory prosegment. J. Biol. Chem. 275, 2349–2358 (2000).
Berry, R. et al. Role of dimerization and substrate exclusion in the regulation of bone morphogenetic protein-1 and mammalian tolloid. Proc. Natl Acad. Sci. USA 106, 8561–8566 (2009).
Takahara, K., Lyons, G. E. & Greenspan, D. S. Bone morphogenetic protein-1 and a mammalian tolloid homologue (mTld) are encoded by alternatively spliced transcripts which are differentially expressed in some tissues. J. Biol. Chem. 269, 32572–32578 (1994).
Muir, A. M. et al. Induced ablation of Bmp1 and Tll1 produces osteogenesis imperfecta in mice. Hum. Mol. Genet. 23, 3085–3101 (2014).
Sieron, L. et al. Functional and structural studies of tolloid-like 1 mutants associated with atrial-septal defect 6. Biosci. Rep. 39, BSR20180270 (2019).
Takahara, K., Brevard, R., Hoffman, G. G., Suzuki, N. & Greenspan, D. S. Characterization of a novel gene product (mammalian tolloid-like) with high sequence similarity to mammalian tolloid/bone morphogenetic protein-1. Genomics 34, 157–165 (1996).
Lee, S. J. Genetic analysis of the role of proteolysis in the activation of latent myostatin. PLoS ONE 3, e1628 (2008).
Scott, I. C. et al. Mammalian BMP-1/Tolloid-related metalloproteinases, including novel family member mammalian Tolloid-like 2, have differential enzymatic activities and distributions of expression relevant to patterning and skeletogenesis. Dev. Biol. 213, 283–300 (1999).
Augustin, H., Adcott, J., Elliott, C. J. H. & Partridge, L. Complex roles of myoglianin in regulating adult performance and lifespan. Fly 11, 284–289 (2017).
Farooq, M. et al. Histone deacetylase 3 (hdac3) is specifically required for liver development in zebrafish. Dev. Biol. 317, 336–353 (2008).
Wang, C. et al. Deletion of mstna and mstnb impairs the immune system and affects growth performance in zebrafish. Fish Shellfish Immunol. 72, 572–580 (2018).
Chiang, Y. A. et al. TALENs-mediated gene disruption of myostatin produces a larger phenotype of medaka with an apparently compromised immune system. Fish Shellfish Immunol. 48, 212–220 (2016).
Lee, C. Y. et al. Suppression of myostatin with vector-based RNA interference causes a double-muscle effect in transgenic zebrafish. Biochem. Biophys. Res. Commun. 387, 766–771 (2009).
Acosta, J., Carpio, Y., Borroto, I., Gonzalez, O. & Estrada, M. P. Myostatin gene silenced by RNAi show a zebrafish giant phenotype. J. Biotechnol. 119, 324–331 (2005).
Fuentes, E. N. et al. Transient inactivation of myostatin induces muscle hypertrophy and overcompensatory growth in zebrafish via inactivation of the SMAD signaling pathway. J. Biotechnol. 168, 295–302 (2013).
Liu, J. P. The function of growth/differentiation factor 11 (Gdf11) in rostrocaudal patterning of the developing spinal cord. Development 133, 2865–2874 (2006).
Kim, G. D. et al. Generation of myostatin-knockout chickens mediated by D10A-Cas9 nickase. FASEB J. 34, 5688–5696 (2020).
Bhattacharya, T. K., Shukla, R., Chatterjee, R. N. & Bhanja, S. K. Comparative analysis of silencing expression of myostatin (MSTN) and its two receptors (ACVR2A and ACVR2B) genes affecting growth traits in knock down chicken. Sci. Rep. 9, 7789 (2019).
Manceau, M. et al. Myostatin promotes the terminal differentiation of embryonic muscle progenitors. Genes Dev. 22, 668–681 (2008).
Amthor, H., Otto, A., Macharia, R., McKinnell, I. & Patel, K. Myostatin imposes reversible quiescence on embryonic muscle precursors. Dev. Dyn. 235, 672–680 (2006).
Yang, W. et al. [Functional characterization of recombinant myostatin and its inhibitory role to chicken muscle development]. Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai) 35, 1016–1022 (2003).
Dichmann, D. S., Yassin, H. & Serup, P. Analysis of pancreatic endocrine development in GDF11-deficient mice. Dev. Dyn. 235, 3016–3025 (2006).
Dai, Z. et al. Growth differentiation factor 11 attenuates liver fibrosis via expansion of liver progenitor cells. Gut 69, 1104–1115 (2020).
Tang, F., Ling, C. & Liu, J. Reduced expression of growth differentiation factor 11 promoted the progression of chronic obstructive pulmonary disease by activating the AKT signaling pathway. Biomed. Pharmacother. 103, 691–698 (2018).
Santos, R. et al. Restoration of retinal development in Vsx2 deficient mice by reduction of Gdf11 levels. Adv. Exp. Med. Biol. 723, 671–677 (2012).
Garrido-Moreno, V. et al. GDF-11 prevents cardiomyocyte hypertrophy by maintaining the sarcoplasmic reticulum-mitochondria communication. Pharmacol. Res. 146, 104273 (2019).
Zhao, Y. et al. The neuroprotective and neurorestorative effects of growth differentiation factor 11 in cerebral ischemic injury. Brain Res. 1737, 146802 (2020).
Anqi, X., Ruiqi, C., Yanming, R. & Chao, Y. Neuroprotective potential of GDF11 in experimental intracerebral hemorrhage in elderly rats. J. Clin. Neurosci. 63, 182–188 (2019).
Zhang, J. et al. GDF11 improves angiogenic function of EPCs in diabetic limb ischemia. Diabetes 67, 2084–2095 (2018).
Idkowiak-Baldys, J. et al. Growth differentiation factor 11 (GDF11) has pronounced effects on skin biology. PLoS ONE 14, e0218035 (2019).
Wang, W. et al. GDF11 antagonizes psoriasis-like skin inflammation via suppression of NF-kappaB signaling pathway. Inflammation 42, 319–330 (2019).
Li, Q. et al. Topical GDF11 accelerates skin wound healing in both type 1 and 2 diabetic mouse models. Biochem. Biophys. Res. Commun. 529, 7–14 (2020).
Zhang, Y. et al. GDF11 improves tubular regeneration after acute kidney injury in elderly mice. Sci. Rep. 6, 34624 (2016).
Wang, L. et al. Growth differentiation factor 11 ameliorates experimental colitis by inhibiting NLRP3 inflammasome activation. Am. J. Physiol. Gastrointest. Liver Physiol. 315, G909–G920 (2018).
Li, L. et al. Positive effects of a young systemic environment and high growth differentiation factor 11 levels on chondrocyte proliferation and cartilage matrix synthesis in old mice. Arthritis Rheumatol. 72, 1123–1133 (2020).
Li, W. et al. GDF11 antagonizes TNF-alpha-induced inflammation and protects against the development of inflammatory arthritis in mice. FASEB J. 33, 3317–3329 (2019).
Walker, R. G. et al. Exogenous GDF11, but not GDF8, reduces body weight and improves glucose homeostasis in mice. Sci. Rep. 10, 4561 (2020).
Katsimpardi, L. et al. Systemic GDF11 stimulates the secretion of adiponectin and induces a calorie restriction-like phenotype in aged mice. Aging Cell 19, e13038 (2020).
Li, H. et al. GDF11 attenuates development of type 2 diabetes via improvement of islet beta-cell function and survival. Diabetes 66, 1914–1927 (2017).
Mei, W. et al. GDF11 protects against endothelial injury and reduces atherosclerotic lesion formation in apolipoprotein E-null mice. Mol. Ther. 24, 1926–1938 (2016).
Finkenzeller, G., Stark, G. B. & Strassburg, S. Growth differentiation factor 11 supports migration and sprouting of endothelial progenitor cells. J. Surg. Res. 198, 50–56 (2015).
Zhou, Y., Song, L., Ni, S., Zhang, Y. & Zhang, S. Administration of rGDF11 retards the aging process in male mice via action of anti-oxidant system. Biogerontology 20, 433–443 (2019).
Wang, W. et al. GDF11 impairs liver regeneration in mice after partial hepatectomy. Clin. Sci. 133, 2069–2084 (2019).
Liu, A. et al. Growth differentiation factor 11 worsens hepatocellular injury and liver regeneration after liver ischemia reperfusion injury. FASEB J. 32, 5186–5198 (2018).
Pons, M. et al. GDF11 induces kidney fibrosis, renal cell epithelial-to-mesenchymal transition, and kidney dysfunction and failure. Surgery 164, 262–273 (2018).
Suragani, R. N. et al. Transforming growth factor-beta superfamily ligand trap ACE-536 corrects anemia by promoting late-stage erythropoiesis. Nat. Med. 20, 408–414 (2014).
Guo, W. et al. Joint dysfunction and functional decline in middle age myostatin null mice. Bone 83, 141–148 (2016).
Zhang, C. et al. Myostatin-null mice exhibit delayed skin wound healing through the blockade of transforming growth factor-beta signaling by decorin. Am. J. Physiol. Cell Physiol. 302, C1213–C1225 (2012).
Hoogaars, W. M. H. & Jaspers, R. T. Past, present, and future perspective of targeting myostatin and related signaling pathways to counteract muscle atrophy. Adv. Exp. Med. Biol. 1088, 153–206 (2018).
Mendias, C. L. et al. Haploinsufficiency of myostatin protects against aging-related declines in muscle function and enhances the longevity of mice. Aging Cell 14, 704–706 (2015).
Gay, S., Jublanc, E., Bonnieu, A. & Bacou, F. Myostatin deficiency is associated with an increase in number of total axons and motor axons innervating mouse tibialis anterior muscle. Muscle Nerve 45, 698–704 (2012).
Elkasrawy, M., Fulzele, S., Bowser, M., Wenger, K. & Hamrick, M. Myostatin (GDF-8) inhibits chondrogenesis and chondrocyte proliferation in vitro by suppressing Sox-9 expression. Growth Factors 29, 253–262 (2011).
McPherron, A. C. & Lee, S. J. Suppression of body fat accumulation in myostatin-deficient mice. J. Clin. Invest. 109, 595–601 (2002).
Mendias, C. L., Bakhurin, K. I. & Faulkner, J. A. Tendons of myostatin-deficient mice are small, brittle, and hypocellular. Proc. Natl Acad. Sci. USA 105, 388–393 (2008).
Chen, Y. et al. Myostatin regulates glucose metabolism via the AMP-activated protein kinase pathway in skeletal muscle cells. Int. J. Biochem. Cell Biol. 42, 2072–2081 (2010).
Qin, Y. et al. Myostatin inhibits osteoblastic differentiation by suppressing osteocyte-derived exosomal microRNA-218: a novel mechanism in muscle-bone communication. J. Biol. Chem. 292, 11021–11033 (2017).
Hamrick, M. W. et al. Recombinant myostatin (GDF-8) propeptide enhances the repair and regeneration of both muscle and bone in a model of deep penetrant musculoskeletal injury. J. Trauma 69, 579–583 (2010).
Hittel, D. S. et al. Myostatin decreases with aerobic exercise and associates with insulin resistance. Med. Sci. Sports Exerc. 42, 2023–2029 (2010).
Zhao, L. et al. TERT assists GDF11 to rejuvenate senescent VEGFR2(+)/CD133(+) cells in elderly patients with myocardial infarction. Lab. Investig. 99, 1661–1688 (2019).
Fenaux, P. et al. Luspatercept in patients with lower-risk myelodysplastic syndromes. N. Engl. J. Med. 382, 140–151 (2020).
Mendell, J. R. et al. A phase 1/2a follistatin gene therapy trial for becker muscular dystrophy. Mol. Ther. 23, 192–201 (2015).
Fulzele, S. et al. Role of myostatin (GDF-8) signaling in the human anterior cruciate ligament. J. Orthop. Res. 28, 1113–1118 (2010).
Hjorth, M. et al. Myostatin in relation to physical activity and dysglycaemia and its effect on energy metabolism in human skeletal muscle cells. Acta Physiol. 217, 45–60 (2016).
Abdulkadyrov, K. M. et al. Sotatercept in patients with osteolytic lesions of multiple myeloma. Br. J. Haematol. 165, 814–823 (2014).
This work was supported by the Creative-Pioneering Researchers Program through Seoul National University (SNU), the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2018R1D1A1B07045334), and the NRF grant funded by the Korean government (Ministry of Science and ICT) (NRF-2020R1A2C1010359).
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Suh, J., Lee, YS. Similar sequences but dissimilar biological functions of GDF11 and myostatin. Exp Mol Med 52, 1673–1693 (2020). https://doi.org/10.1038/s12276-020-00516-4