Early life alcohol exposure primes hypothalamic microglia to later-life hypersensitivity to immune stress: possible epigenetic mechanism

Article metrics


Growing evidence has shown that developmental alcohol exposure induces central nervous system inflammation and microglia activation, which may contribute to long-term health conditions, such as fetal alcohol spectrum disorders. These studies sought to investigate whether neonatal alcohol exposure during postnatal days (PND) 2–6 in rats (third trimester human equivalent) leads to long-term disruption of the neuroimmune response by microglia. Exposure to neonatal alcohol resulted in acute increases in activation and inflammatory gene expression in hypothalamic microglia including tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). Adults with neonatal alcohol pre-exposure (alcohol fed; AF) animals showed an exaggerated peripheral stress hormonal response to an immune challenge (lipopolysaccharides; LPS). In addition, there were significantly more microglia present in the hypothalamus of adult AF animals, and their hypothalamic microglia showed more cluster of differentiation molecule 11b (Cd11b) activation, TNF-α expression, and IL-6 expression in response to LPS. Interestingly, blocking microglia activation with minocycline treatment during PND 2–6 alcohol exposure ameliorated the hormonal and microglial hypersensitivity to LPS in AF adult animals. Investigation of possible epigenetic programming mechanisms by alcohol revealed neonatal alcohol decreased several repressive regulators of transcription in hypothalamic microglia, while concomitantly increasing histone H3 acetyl lysine 9 (H3K9ac) enrichment at TNF-α and IL-6 promoter regions. Importantly, adult hypothalamic microglia from AF animals showed enduring increases in H3K9ac enrichment of TNF-α and IL-6 promoters both at baseline and after LPS exposure, suggesting a possible epigenetic mechanism for the long-term immune disruption due to hypothalamic microglial priming.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5


  1. 1.

    May PA, et al. Prevalence of fetal alcohol spectrum disorders in 4 US communities. JAMA. 2018;319:474–82.

  2. 2.

    Lange S, Probst C, Gmel G, Rehm J, Burd L, Popova S. Global prevalence of fetal alcohol spectrum disorder among children and youth: a systematic review and meta-analysis. JAMA Pediatr. 2017;171:948–56.

  3. 3.

    Riley EP, Infante MA, Warren KR. Fetal alcohol spectrum disorders: an overview. Neuropsychol Rev. 2011;21:73–80.

  4. 4.

    Caputo C, Wood E, Jabbour L. Impact of fetal alcohol exposure on body systems: a systematic review. Birth Defects Res C. 2016;108:174–80.

  5. 5.

    Moore EM, Riley EP. What happens when children with fetal alcohol spectrum disorders become adults? Curr Dev Disord Rep. 2015;2:219–27.

  6. 6.

    Zhang X, Sliwowska JH, Weinberg J. Prenatal alcohol exposure and fetal programming: effects on neuroendocrine and immune function. Exp Biol Med. 2005;230:376–88.

  7. 7.

    Mead EA, Sarkar DK. Fetal alcohol spectrum disorders and their transmission through genetic and epigenetic mechanisms. Front Genet. 2014;5:154.

  8. 8.

    Johnson S, Knight R, Marmer DJ, Steele RW. Immune deficiency in fetal alcohol syndrome. Pediatr Res. 1981;15:908–11.

  9. 9.

    Olah M, Biber K, Vinet J, Boddeke HW. Microglia phenotype diversity. CNS Neurol Disord Drug Targets. 2011;10:108–18.

  10. 10.

    Chastain LG, Sarkar DK. Role of microglia in regulation of ethanol neurotoxic action. Int Rev Neurobiol. 2014;118:81–103.

  11. 11.

    Crews FT, Sarkar DK, Qin L, Zou J, Boyadjieva N, Vetreno RP. Neuroimmune function and the consequences of alcohol exposure. Alcohol Res. 2015;37:331–41. 344-51

  12. 12.

    He J, Crews FT. Increased MCP-1 and microglia in various regions of the human alcoholic brain. Exp Neurol. 2008;210:349–58.

  13. 13.

    Alfonso-Loeches S, Pascual M, Guerri C. Gender differences in alcohol-induced neurotoxicity and brain damage. Toxicology. 2013;311:27–34.

  14. 14.

    Wong EL, Stowell RD, Majewska AK. What the spectrum of microglial functions can teach us about fetal alcohol spectrum disorder. Front Synaptic Neurosci. 2017;9:11.

  15. 15.

    Boyadjieva NI, Sarkar DK. Role of microglia in ethanol's apoptotic action on hypothalamic neuronal cells in primary cultures. Alcohol Clin Exp Res. 2010;34:1835–42.

  16. 16.

    Shrivastava P, et al. Mu-opioid receptor and delta-opioid receptor differentially regulate microglial inflammatory response to control proopiomelanocortin neuronalapoptosis in the hypothalamus: effects of neonatal alcohol. J Neuroinflamm. 2017;14:83.

  17. 17.

    Bodnar TS, Hill LA, Weinberg J. Evidence for an immune signature of prenatalalcohol exposure in female rats. Brain Behav Immun. 2016;58:130–41.

  18. 18.

    Topper LA, Baculis BC, Valenzuela CF. Exposure of neonatal rats to alcohol has differential effects on neuroinflammation and neuronal survival in the cerebellum and hippocampus. J Neuroinflamm. 2015;12:160.

  19. 19.

    Tiwari V, Chopra K. Resveratrol abrogates alcohol-induced cognitive deficits by attenuating oxidative-nitrosative stress and inflammatory cascade in the adult rat brain. Neurochem Int. 2013;62:861–9.

  20. 20.

    McClain JA, et al. Adolescent binge alcohol exposure induces long-lasting partial activation of microglia. Brain Behav Immun. 2011;25(Suppl 1):S120–8.

  21. 21.

    Vetreno RP, Lawrimore CJ, Rowsey PJ, Crews FT. Persistent adult neuroimmune activation and loss of hippocampal neurogenesis following adolescent ethanol exposure: blockade by exercise and the anti-inflammatory drug indomethacin. Front Neurosci. 2018;12:200.

  22. 22.

    Williamson LL, Sholar PW, Mistry RS, Smith SH, Bilbo SD. Microglia and memory: modulation by early-life infection. J Neurosci. 2011;31:15511–21.

  23. 23.

    Fenn AM, Gensel JC, Huang Y, Popovich PG, Lifshitz J, Godbout JP. Immune activation promotes depression 1 month after diffuse brain injury: a role for primed microglia. Biol Psychiatry. 2014;76:575–84.

  24. 24.

    Niraula A, Sheridan JF, Godbout JP. Microglia priming with aging and stress. Neuropsychopharmacology. 2017;42:318–33.

  25. 25.

    Perry VH, Holmes C. Microglial priming in neurodegenerative disease. Nat Rev Neurol. 2014;10:217–24.

  26. 26.

    Kaminska B, Mota M, Pizzi M. Signal transduction and epigenetic mechanisms in the control of microglia activation during neuroinflammation. Biochim Biophys Acta. 2016;1862:339–51.

  27. 27.

    Chater-Diehl EJ, Laufer BI, Singh SM. Changes to histone modifications following prenatal alcohol exposure: an emerging picture. Alcohol. 2017;60:41–52.

  28. 28.

    Laufer BI, Chater-Diehl EJ, Kapalanga J, Singh SM. Long-term alterations to DNA methylation as a biomarker of prenatal alcohol exposure: from mouse models to human children with fetal alcohol spectrum disorders. Alcohol. 2017;60:67–75.

  29. 29.

    Hellemans KG, et al. Prenatal alcohol exposure: fetal programming and later life vulnerability to stress, depression and anxiety disorders. Neurosci Biobehav Rev. 2010;34:791–807.

  30. 30.

    Weinberg J, et al. Prenatal alcohol exposure: foetal programming, the hypothalamic-pituitary-adrenal axis and sex differences in outcome. J Neuroendocrinol. 2008;20:470–88.

  31. 31.

    Bilbo SD, Frank A. Beach award: programming of neuroendocrine function by early-life experience: a critical role for the immune system. Horm Behav. 2013;63:684–91.

  32. 32.

    Klintsova AY, Hamilton GF, Boschen KE. Long-term consequences of developmental alcohol exposure on brain structure and function: therapeutic benefits of physical activity. Brain Sci. 2012;3:1–38.

  33. 33.

    Paxinos G, Franklin KBJ. The mouse brain in stereotaxic coordinates. San Diego, CA: Academic; 2001.

  34. 34.

    Ramachandra R, Subramanian T. Atlas of the neonatal rat brain. Boca Raton, FL: CRC Press; 2011.

  35. 35.

    Kane CJ, et al. Protection of neurons and microglia against ethanol in a mouse model of fetal alcohol spectrum disorders by peroxisome proliferator-activated receptor-γ agonists. Brain Behav Immun. 2011;25(Suppl 1):S137–45.

  36. 36.

    Ahlers KE, Karaçay B, Fuller L, Bonthius DJ, Dailey ME. Transient activation of microglia following acute alcohol exposure in developing mouse neocortex is primarily driven by BAX-dependent neurodegeneration. Glia. 2015;63:1694–713.

  37. 37.

    Boschen KE, Ruggiero MJ, Klintsova AY. Neonatal binge alcohol exposure increases microglial activation in the developing rat hippocampus. Neuroscience. 2016;324:355–66.

  38. 38.

    Marshall SA, Geil CR, Nixon K. Prior binge ethanol exposure potentiates the microglial response in a model of alcohol-induced neurodegeneration. Brain Sci. 2016;6:pii: E16.

  39. 39.

    Qin L, He J, Hanes RN, Pluzarev O, Hong JS, Crews FT. Increased systemic and brain cytokine production and neuroinflammation by endotoxin following ethanol treatment. J Neuroinflamm. 2008;5:10.

  40. 40.

    Walter TJ, Vetreno RP, Crews FT. Alcohol and stress activation of microglia and neurons: brain regional effects. Alcohol Clin Exp Res. 2017;41:2066–81.

  41. 41.

    Möller T, et al. Critical data-based re-evaluation of minocycline as a putative specific microglia inhibitor. Glia. 2016;64:1788–94.

  42. 42.

    Kobayashi K, et al. Minocycline selectively inhibits M1 polarization of microglia. Cell Death Dis. 2013;4:e525.

  43. 43.

    Qin L, Crews FT. Chronic ethanol increases systemic TLR3 agonist-induced neuroinflammation and neurodegeneration. J Neuroinflamm. 2012;9:130.

  44. 44.

    Agrawal RG, Hewetson A, George CM, Syapin PJ, Bergeson SE. Minocycline reduces ethanol drinking. Brain Behav Immun. 2011;25(Suppl 1):S165–9.

  45. 45.

    Garro AJ, McBeth DL, Lima V, Lieber CS. Ethanol consumption inhibits fetal DNA methylation in mice: implications for the fetal alcohol syndrome. Alcohol Clin Exp Res. 1991;15:395–8.

  46. 46.

    Chen Y, Ozturk NC, Zhou FC. DNA methylation program in developing hippocampus and its alteration by alcohol. PLoS One. 2013;8:e60503.

  47. 47.

    Kim P, et al. Effects of ethanol exposure during early pregnancy in hyperactive, inattentive and impulsive behaviors and MeCP2 expression in rodent offspring. Neurochem Res. 2013;38:620–31.

  48. 48.

    Gangisetty O, Bekdash R, Maglakelidze G, Sarkar DK. Fetal alcohol exposure alters proopiomelanocortin gene expression and hypothalamic-pituitary-adrenal axis function via increasing MeCP2 expression in the hypothalamus. PLoS One. 2014;9:e113228.

  49. 49.

    Moonat S, Sakharkar AJ, Zhang H, Tang L, Pandey SC. Aberrant histone deacetylase2-mediated histone modifications and synaptic plasticity in the amygdala predisposes to anxiety and alcoholism. Biol Psychiatry. 2013;73:763–73.

  50. 50.

    Sakharkar AJ, et al. Effects of histone deacetylase inhibitors on amygdaloid histone acetylation and neuropeptide Y expression: a role in anxiety-like and alcohol-drinking behaviours. Int J Neuropsychopharmacol. 2014;17:1207–20.

  51. 51.

    Veazey KJ, Parnell SE, Miranda RC, Golding MC. Dose-dependent alcohol-induced alterations in chromatin structure persist beyond the window of exposure and correlate with fetal alcohol syndrome birth defects. Epigenetics Chromatin. 2015;8:39.

  52. 52.

    Rybtsova N, Leimgruber E, Seguin-Estévez Q, Dunand-Sauthier I, Krawczyk M, Reith W. Transcription-coupled deposition of histone modifications during MHC class II gene activation. Nucleic Acids Res. 2007;35:3431–41.

  53. 53.

    Falvo JV, Jasenosky LD, Kruidenier L, Goldfeld AE. Epigenetic control of cytokine gene expression: regulation of the TNF/LT locus and T helper cell differentiation. Adv Immunol. 2013;118:37–128.

  54. 54.

    Fann M, et al. Histone acetylation is associated with differential gene expression in the rapid and robust memory CD8(+) T-cell response. Blood. 2006;108:3363–70.

  55. 55.

    Ito K, et al. Decreased histone deacetylase activity in chronic obstructive pulmonary disease. N Engl J Med. 2005;352:1967–76.

  56. 56.

    Cedar H, Bergman Y. Linking DNA methylation and histone modification: patterns and paradigms. Nat Rev Genet. 2009;10:295–304.

Download references


We thank Gayathri Narayanan and Rahul Nayar for their assistance in gene expression studies. We thank Gregory Berger for his technical assistance in animal experiments.

Author information

Correspondence to Dipak K. Sarkar.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Further reading