Aging & Longevity

The present paper provides the first integrated assessment of the capacity of the flavonol, fisetin, to induce hormetic dose responses. Fisetin was shown to induce hormetic dose responses in cellular and in vivo animal model systems affecting a broad range of endpoints of potential therapeutic and public health significance across the entire lifespan. Fisetin was effective in slowing aging processes, acting as a senolytic agent in multiple organ systems, in an hormetic fashion. In addition,...

Spermidine is a naturally occurring polyamine present in all cells and is necessary for viability in eukaryotic cells. The cellular levels of spermidine decline as an organism ages, and its supplementation has been found to extend lifespan in yeast, worms, flies, mice, and human cultured cells. The lifespan extending effect of spermidine is thought to be due to its ability to induce autophagy, a turnover of cellular components. Mitochondrial dysfunction is believed to be a major driver of the...

Chaperone-mediated autophagy (CMA) is a selective autophagic pathway that targets specific proteins for lysosomal degradation, playing a crucial role in maintaining cellular homeostasis. Recent research has highlighted the involvement of CMA in aging and age-related diseases, yet its regulation remains complex. The study by Khawaja et al. provides novel insights into the sex-specific and cell-type-specific regulation of CMA during aging. This commentary discusses the key findings of this study,...

ObjectiveWe compared pain prevalence and intensity between caregivers and non-caregivers, as well as between different types of caregivers.MethodUsing two rounds of data from the National Social Life, Health, and Aging Project, we used regression models to analyze differences in pain prevalence and intensity between caregivers and non-caregivers at baseline (2010-2011) and follow-up (2015-2016). The sample consisted of 2332 participants aged 62 and older (352 caregivers and 1980...

Bone fractures and related complications are a significant concern for older adults, particularly with the growing aging population. Therapeutic interventions that promote bone tissue regeneration are attractive for geriatric fracture repair. Extracellular adenosine plays a key role in bone homeostasis and regeneration. Herein, we examined the changes in extracellular adenosine with aging and the potential of local delivery of adenosine to promote fracture healing using aged mice. Extracellular...

The mitochondrial unfolded protein response (UPR^(mt)), a mitochondria-to-nucleus retrograde pathway that promotes the maintenance of mitochondrial function in response to stress, plays an important role in promoting lifespan extension in Caenorhabditis elegans^(1,2). However, its role in mammals, including its contributions to development or cell fate decisions, remains largely unexplored. Here, we show that transient UPR^(mt) activation occurs during somatic reprogramming in mouse embryonic...

Neuroimaging studies have shown age-related alterations in brain structure and function supporting semantic knowledge, although the significance of these is not fully understood. Herein, we report novel temporal, spectral, and spatial information on age-related changes from the largest dynamic functional mapping study of semantic processing. Participants (N = 130, age range 21-87 years, M(age) = 51.05, SD = 14.73, 68 females) performed a semantic judgement task during magnetoencephalography...

Mitochondrial dysfunction is a hallmark of cellular senescence. Here, we investigated whether senescent cells release mitochondrial (mt)DNA into the extracellular space and its impact on innate immunity. We found that both primary senescent cells and tumor cells undergoing therapy-induced senescence actively released mtDNA into the extracellular environment. mtDNA released by senescent cells was packaged within extracellular vesicles and selectively transferred to polymorphonuclear...

To maintain tissue homeostasis, many cells reside in a quiescent state until prompted to divide. The reactivation of quiescent cells is perturbed with aging and may underlie declining tissue homeostasis and resiliency. The unfolded protein response regulators IRE-1 and XBP-1 are required for the reactivation of quiescent cells in developmentally L1-arrested C. elegans. Utilizing a forward genetic screen in C. elegans, we discovered that macroautophagy targets protein aggregates to lysosomes in...

Ceria nanoparticles supported on alumina are widely used in various catalytic reactions, particularly in conjunction with platinum group metals (PGMs)^(1-9). Here we found that treating these catalysts at temperatures between 750 and about 1,000 °C in the presence of CO and NO in steam (reactive treatment under reducing atmosphere) leads to the dispersion of ceria nanoparticles into high-density 2D (roughly one atomic layer thin) Ce(x)O(y) domains, as confirmed by microscopy, X-ray photoelectron...

Core body temperature (T(b)) is a long-established determinant of longevity across species. In this Perspective, we first summarize evidence demonstrating that reducing T(b) increases lifespan and that lowered T(b) contributes to the antiaging effects of calorie restriction. Next, we discuss recent data that diverge from prior hypotheses on the mechanisms by which T(b) affects longevity, suggesting these are limited neither to the thermodynamics of nonenzymatic chemical reactions, nor reduced...

Peripheral arterial disease (PAD) is more prevalent in individuals with type 2 diabetes mellitus (T2DM). The most severe complication of PAD is chronic limb-threatening ischemia (CLTI), which is associated with major adverse cardiovascular events (MACE) and major adverse limb events (MALE) following lower limb revascularization (LER). This study investigates the relationship between baseline levels of Klotho and FGF23 and the risk of cardiovascular and limb-related outcomes after LER in a...

This book chapter will focus on modifications to chromatin itself, how chromatin modifications are regulated, and how these modifications are deciphered by the cell to impact aging. In this chapter, we will review how chromatin modifications change with age, examine how chromatin-modifying enzymes have been shown to regulate aging and healthspan, discuss how some of these epigenetic changes are triggered and how they can regulate the lifespan of the individual and its naïve descendants, and...

Dietary restriction (DR) is a well-established method for extending lifespan across various species, including C. elegans. Among the different DR regimens, axenic dietary restriction (ADR), in which worms are grown in a nutrient-rich sterile liquid medium, yields the most powerful lifespan extension. However, the molecular mechanisms underlying this longevity phenotype remain largely unexplored. Through a pilot screen of candidate genes, we identified the proprotein convertase BLI-4 as a crucial...

CONCLUSION: These findings suggested a substantial link between elevated B2M levels and cognitive decline among U.S. older adults, partly mediated through the faster pace of aging. This correlation highlights the potential of B2M as a biomarker for early detection and therapeutic intervention of aging-related cognitive decline.

The influence of gut microbes on aging has been reported in several studies, but the mediating pathways of gut microbiota, whether there is a causal relationship between the two, and biomarker screening and validation have not been fully discussed. In this study, Mendelian Randomization (MR) and Linkage Disequilibrium Score Regression (LDSC) are used to systematically investigate the associations between gut microbiota, three aging indicators, and 14 age-related diseases. Additionally, this...

Cognitive decline has been postulated to predispose to presbyphagia but the neurophysiological basis of this interaction is unclear. To investigate the role of cognition for compensatory resource allocation within the swallowing network and behavioral swallowing performance in dual-task cognitive and motor interference in ageing, volunteers ≥ 70 years of age without preexisting diseases causing dysphagia were investigated using Flexible Endoscopic Evaluation of Swallowing (FEES) including a...

Aging is associated with a progressive decline in circulating insulin-like growth factor- 1 (IGF- 1) levels in humans, which has been implicated in the pathogenesis of sarcopenia. IGF- 1 is an anabolic hormone that plays a dual role in maintaining skeletal muscle health, acting both directly on muscle fibers to promote growth and indirectly by supporting the vascular network that sustains muscle perfusion. However, the microvascular consequences of IGF- 1 deficiency in aging muscle remain poorly...

With aging, the hippocampal formation shows variable structural atrophy, which is associated with a decline in cognitive performance. Bilingualism is related to higher hippocampal gray matter volume (GMV), potentially representing a form of brain reserve in aging. However, the differential influence of bilingualism on hippocampal subregions remains unclear. Thus, we investigated GMV differences and differences in age-GMV relationships between mono- and bilinguals in the hippocampal formation and...

Longevity research aims to extend the healthspan while minimizing the duration of disability and morbidity, known as the sickspan. Most longevity interventions in model organisms extend healthspan, but it is not known whether they compress sickspan relative to the lifespan. Here, we present a theory that predicts which interventions compress relative sickspan, based on the shape of the survival curve. Interventions such as caloric restriction that extend mean lifespan while preserving the shape...