Volume 1 Issue 10, October 2021

A new study provides broad evidence that older people are more generous than their younger counterparts, but that they favor local over global giving. In light of population aging and the relative wealth controlled by older citizens, it is important to identify the factors that contribute to these differences.

The apolipoprotein E gene ε4 allele (APOE4) is the strongest genetic risk factor for Alzheimer’s disease (AD). Over 60% of patients have at least one APOE4 allele. A drug discovery approach targeting aging and AD transcriptomic signatures suggests bumetanide might prevent or treat AD in people with the APOE4/APOE4 genotype.

This Review summarizes current research on cellular senescence including its molecular basis and examines how drugs may be targeted against senescent cells to treat age-related multimorbidities.

Cutler et al. found that age predicted individuals’ likelihood to engage in prosocial behaviors such as social distancing during COVID-19 and charitable donations. Older adults across the world were more willing to help but also demonstrated stronger in-group preferences, donating less to international charities.

Using live imaging, the study shows, in mice, that epithelial cells escape from the hair follicle stem cell compartment during aging. Stem cell escape is associated with reduced cell adhesion and extracellular matrix gene expression and leads to hair follicle miniaturization.

The hypothalamus controls systemic aging via involving the production of gonadotropin-releasing hormone (GnRH). The authors show that aging is preceded by irregularity and acceleration of GnRH pulses, while lowering GnRH pulse frequency by castration or optogenetically slows aging and promotes longevity.

The authors found that the Alzheimer’s disease-linked APOEε4 allele may prime microglia towards a phagocytic and pro-inflammatory state in the normal aging brain, even before Alzheimer’s amyloid plaques and neurofibrillary tangles develop.

Through computational drug repurposing, Taubes et al. identified bumetanide as a potential drug for APOE4-related Alzheimer’s disease (AD). The effectiveness of bumetanide was validated in AD mouse models and via real-world health record databases.

A systematic review examining evidence from 32 studies across five countries on associations between care home ownership and COVID-19 found that for-profit care homes were linked to worse COVID-19 outcomes (infections and mortality) compared to non-profit and public sector homes.

Wang et al. report a mouse model for targeting of cells with high p21 expression. Using this model, they are able to monitor, sort, image, eliminate or modulate these cells in vivo, which could be a valuable tool to study senescent cells.