Aging & Longevity

Fibrosis and accumulation of senescent cells are common tissue changes associated with aging. Here, we show that the CDK inhibitor p21 (CDKN1A), known to regulate the cell cycle and the viability of senescent cells, also controls the expression of extracellular matrix (ECM) components in senescent and proliferating cells of the fibrotic lung, in a manner dependent on CDK4 and Rb phosphorylation. p21 knockout protects mice from the induction of lung fibrosis. Moreover, inducible p21 silencing...

Acylcarnitine (ACar) is a novel fuel source for activating thermogenesis in brown adipose tissue (BAT). However, whether ACar metabolism underlies BAT thermogenesis decline with aging remain unclear. Here, the L-carnitine-treated young and aging mice were used to investigate the effects of activation of ACar metabolism on BAT thermogenesis during aging. We showed that long term L-carnitine feeding, which results in an elevation in circulating ACar levels, failed to improve cold sensitivity of...

No abstract

The main genetic risk factor for Alzheimer's disease (AD) is the apolipoprotein E ε4 allele (APOE4). AD risk associated with APOE4 disproportionately affects women. Furthermore, human and rodent studies indicate that the cognitive deficits associated with APOE4 are greater in females. One modifiable AD risk factor is obesity during middle age. Given that approximately two-thirds of US adults are overweight, it is important to understand how obesity affects AD risk, how it interacts with APOE4,...

The cerebral cortex displays a bewildering diversity of shapes and sizes across and within species. Despite this diversity, we present a universal multi-scale description of primate cortices. We show that all cortical shapes can be described as a set of nested folds of different sizes. As neighbouring folds are gradually merged, the cortices of 11 primate species follow a common scale-free morphometric trajectory, that also overlaps with over 70 other mammalian species. Our results indicate that...

As only 10% of the broiler breeder flock is roosters, their fertility is very important. The rooster sperm plasma membrane has high concentrations of polyunsaturated fatty acids that are sensitive to oxidative stress. Lipid peroxidation can change membrane structure, permeability, and fluidity, adversely affecting the acrosome reaction and fertility. Aging roosters have decreases in sexual behavior, serum androgen concentrations, sperm quantity and quality, and fertility. Low fertility in aging...

Epilepsy is a common neurological condition that arises from dysfunctional neuronal circuit control due to either acquired or innate disorders. Autophagy is an essential neuronal housekeeping mechanism, which causes severe proteotoxic stress when impaired. Autophagy impairment has been associated to epileptogenesis through a variety of molecular mechanisms. Vici Syndrome (VS) is the paradigmatic congenital autophagy disorder in humans due to recessive variants in the ectopic P-granules autophagy...

CONCLUSION: The expression of circulating small ncRNAs were comprehensively characterized, revealing distinct signatures in older adults with both low muscle strength and physical performance compared to normal individuals. Although preliminary, this characterization can advance small ncRNA research on age-related declines in muscle strength and physical performance by providing foundational data for further investigation.

Changes to neuronal connectivity are believed to be a key factor in cognitive impairments associated with normal aging. Because of its effect on activities of daily living, deficient motor control is a critical type of cognitive decline to understand. Diminished inhibitory networks in the cortex are implicated in such motor control deficits, pointing to the connectivity of inhibitory cortical interneurons as an important area for study. Here, we used chronic two-photon microscopy to track the...

The most cutting-edge issue in the research on aging is the quest for biomarkers that transcend molecular and cellular domains to encompass organismal-level implications. We recently hypothesized the role of Autonomic Nervous System (ANS) imbalance in this context. Studies on ANS functions during aging highlighted an imbalance towards heightened sympathetic nervous system (SNS) activity, instigating a proinflammatory milieu, and attenuated parasympathetic nervous system (PNS) function, which...

The recent, controversial approval of antibody-based treatments for Alzheimer's disease (AD) is fueling a heated debate on the molecular determinants of this condition. The discussion should also incorporate a critical revision of the limitations of preclinical mouse models in advancing our understanding of AD. We critically discuss the limitations of animal models, stressing the need for careful consideration of how experiments are designed and results interpreted. We identify the shortcomings...

CONCLUSION: The depression in elderly patient should be reconsidered as a systemic disease, with coexisting major geriatric syndromes (disability, dementia, frailty) and combined pathogenetic mechanisms (metabolic syndrome, impaired renal function, low-grade inflammation, and allostatic load). Cortisol confirmed its role as principal mediator of the aging process in both dementia and metabolic syndrome.

Vaccination-induced protection against influenza is greatly diminished and increasingly heterogeneous with age. We investigated longitudinally (up to five time points) a cohort of 234 vaccinated >65-year-old vaccinees with adjuvanted vaccine FluAd across two independent seasons. System-level analyses of multiomics datasets measuring six modalities and serological data revealed that poor responders lacked time-dependent changes in response to vaccination as observed in responders, suggestive of...

Crohn's disease (CD) is a complex and heterogeneous condition with no perfect preclinical model or cure. To address this, we explore adult stem cell-derived organoids that retain their tissue identity and disease-driving traits. We prospectively create a biobank of CD patient-derived organoid cultures (PDOs) from colonic biopsies of 53 subjects across all clinical subtypes and healthy subjects. Gene expression analyses enabled benchmarking of PDOs as tools for modeling the colonic epithelium in...

Although lifespan extension remains the gold standard for assessing interventions proposed to impact the biology of aging, there are important limitations to this approach. Our reanalysis of lifespan studies from multiple sources suggests that short lifespans in the control group exaggerate the relative efficacy of putative longevity interventions. Results may be exaggerated due to statistical effects (e.g. regression to the mean) or other factors. Moreover, due to the high cost and long...

Inbreeding depression has been documented in various fitness traits in a wide range of species and taxa, however, the mutational basis is not yet well understood. We investigate how putatively deleterious variation influences fitness and is shaped by individual ancestry by re-sequencing complete genomes of 37 individuals in a natural arctic fox (Vulpes lagopus) population subjected to both inbreeding depression and genetic rescue. We find that individuals with high proportion of homozygous loss...

Living longer and healthier boosts individual and family welfare. As part of the World Bank's Healthy Longevity Initiative, we quantified the economic value of achieving the highest possible life span. We estimated the economic value of reducing avoidable mortality, defined as the difference between observed (or projected) mortality and lowest achieved (or projected) mortality, by world regions, sex, and age, between 2000 and 2021, with projection to 2050. In 2019, 69% of mortality, or 40...

With population aging, national health systems face difficult trade-offs in allocating resources. The World Bank launched the Healthy Longevity Initiative to generate evidence for investing in policies that can improve healthy longevity and human capital. As part of this initiative, we quantified the economic value of reducing avoidable mortality from major noncommunicable diseases and injuries. We estimated avoidable mortality-the difference between lowest-achieved mortality frontiers and...

A decline in mitochondrial function is a hallmark of aging and neurodegenerative diseases. It has been proposed that changes in mitochondrial morphology, including fragmentation of the tubular mitochondrial network, can lead to mitochondrial dysfunction, yet the mechanism of this loss of function is unclear. Most proteins contained within mitochondria are nuclear-encoded and must be properly targeted to the mitochondria. Here, we report that sustained mRNA localization and co-translational...

MicroRNA plays a crucial role in post-transcriptional gene regulation and has recently emerged as a factor linked to aging, but the underlying regulatory mechanisms remain incompletely understood. In this study, we observed lifespan-extending effects in miR-80-deficient Caenorhabditis elegans at 20°C but not 25°C. At 20°C, miR-80 deletion leads to NLP-45 upregulation, which positively correlates to increased abu transcripts and extended lifespan. Supportively, we identified miR-80 binding...