Volume 3 Issue 4, April 2023

The ability of adult neural stem cells to produce new neurons (neurogenesis) declines markedly during aging, but exactly how this occurs is largely unknown. Using sophisticated in vivo imaging, a study in Nature Aging shows that aging affects several steps of neurogenesis — most notably, increasing the death of newborn clones.

Epigenetic changes are a driver of senescence and occur during aging. A study in Nature Aging shows how chromatin-mediated loss of transcription fidelity, previously shown in yeast and worms, also occurs in mammalian cells and could constitute a new hallmark of senescence and aging.

We characterized the enterotypes of a large cohort of individuals of 20–117 years of age and found that the gut microbiome of centenarians has features that are usually associated with gut microbiomes of young individuals: dominance of Bacteroides spp., increase in species evenness, enrichment of potentially beneficial Bacteroidetes and depletion of potential pathobionts.

Clinical predictors of type 2 diabetes can be improved by considering blood-based DNA methylation scores. We derive the scores in 9,835 Scottish individuals and then test their performance against clinical predictors in 4,778 additional Scottish volunteers and 1,451 German volunteers.

Using chronic in vivo imaging of the mouse hippocampus over months, this study reveals aging-associated alterations of neural stem cells and their neuronal progeny that lead to reduced clonal output of individual neural stem cells with advancing age.

Cerebrospinal fluid (CSF) tests are used in the clinical diagnosis of Alzheimer’s disease. This study found that CSF tau phosphorylation at two sites (T217 and T205) is a better test for Alzheimer’s disease pathology than currently available tests.

Sen et al. show that, during human cellular senescence and mouse tissue aging, chromatin alterations promote the initiation of transcription from non-canonical sites and lead to deterioration of cellular health.

Xiao et al. report a weaker adaptive immune response in older adults after inactivated SARS-CoV-2 vaccination compared to young adult controls, identifying altered immune cell function and decreased antigen-specific receptor repertoire diversity as potential underlying mechanisms.

The gut microbiome is closely connected to health. Pang et al. explored the gut microbiome and aging in a large cohort of 297 centenarians. The study shows that the gut microbiome in centenarians has a Bacteroides-enriched enterotype and youth-associated features.

Early type 2 diabetes (T2D) risk assessment could help slow or prevent disease onset. Here the authors used blood-based DNA methylation data to develop 10-year risk prediction models for incident T2D. The results show an improvement in performance beyond standard risk factors typically used to predict the risk of T2D onset.