•A recent symposium debate highlighted disagreements and confusion in aging biology.•Symposium participants followed up by completing an online survey.•Survey results show little common ground on ...most questions in aging biology.•However, there is a near-consensus that aging is heterogeneous and multifactorial.•Work is needed to achieve a common paradigm in aging biology.
At a recent symposium on aging biology, a debate was held as to whether or not we know what biological aging is. Most of the participants were struck not only by the lack of consensus on this core question, but also on many basic tenets of the field. Accordingly, we undertook a systematic survey of our 71 participants on key questions that were raised during the debate and symposium, eliciting 37 responses. The results confirmed the impression from the symposium: there is marked disagreement on the most fundamental questions in the field, and little consensus on anything other than the heterogeneous nature of aging processes. Areas of major disagreement included what participants viewed as the essence of aging, when it begins, whether aging is programmed or not, whether we currently have a good understanding of aging mechanisms, whether aging is or will be quantifiable, whether aging will be treatable, and whether many non-aging species exist. These disagreements lay bare the urgent need for a more unified and cross-disciplinary paradigm in the biology of aging that will clarify both areas of agreement and disagreement, allowing research to proceed more efficiently. We suggest directions to encourage the emergence of such a paradigm.
The skin, being the barrier organ of the body, is constitutively exposed to various stimuli impacting its morphology and function. Senescent cells have been found to accumulate with age and may ...contribute to age-related skin changes and pathologies. Natural polyphenols exert many health benefits, including ameliorative effects on skin aging. By affecting molecular pathways of senescence, polyphenols are able to prevent or delay the senescence formation and, consequently, avoid or ameliorate aging and age-associated pathologies of the skin. This review aims to provide an overview of the current state of knowledge in skin aging and cellular senescence, and to summarize the recent in vitro studies related to the anti-senescent mechanisms of natural polyphenols carried out on keratinocytes, melanocytes and fibroblasts. Aged skin in the context of the COVID-19 pandemic will be also discussed.
In my introduction to these three papers on the experience of aging, I begin with my observations on aging in the 9th Stage of Life (a stage added by Erik Erickson in 1984, when he himself was ...nearing death) by talking about my own aging, 87-year-old husband whose end of life included changes in himself that no one who knew him, including himself, would have predicted. Following these thoughts I review the excellent essays that follow, which take the perspectives of aging from both personal and professional perspectives.
Background:
Physical inactivity triggers a rapid loss of muscle mass and function in older adults. Middle-aged adults show few phenotypic signs of aging yet may be more susceptible to inactivity than ...younger adults.
Objective:
The aim was to determine whether leucine, a stimulator of translation initiation and skeletal muscle protein synthesis (MPS), can protect skeletal muscle health during bed rest.
Design:
We used a randomized, double-blind, placebo-controlled trial to assess changes in skeletal MPS, cellular signaling, body composition, and skeletal muscle function in middle-aged adults (
n
= 19; age ± SEM: 52 ± 1 y) in response to leucine supplementation (LEU group: 0.06 g ∙ kg
−1
∙ meal
−1
) or an alanine control (CON group) during 14 d of bed rest.
Results:
Bed rest decreased postabsorptive MPS by 30% ± 9% (CON group) and by 10% ± 10% (LEU group) (main effect for time,
P
< 0.05), but no differences between groups with respect to pre-post changes (group × time interactions) were detected for MPS or cell signaling. Leucine protected knee extensor peak torque (CON compared with LEU group: −15% ± 2% and −7% ± 3%; group × time interaction,
P
< 0.05) and endurance (CON compared with LEU: −14% ± 3% and −2% ± 4%; group × time interaction,
P
< 0.05), prevented an increase in body fat percentage (group × time interaction,
P
< 0.05), and reduced whole-body lean mass loss after 7 d (CON compared with LEU: −1.5 ± 0.3 and −0.8 ± 0.3 kg; group × time interaction,
P
< 0.05) but not 14 d (CON compared with LEU: −1.5 ± 0.3 and −1.0 ± 0.3 kg) of bed rest. Leucine also maintained muscle quality (peak torque/kg leg lean mass) after 14 d of bed-rest inactivity (CON compared with LEU: −9% ± 2% and +1% ± 3%; group × time interaction,
P
< 0.05).
Conclusions:
Bed rest has a profoundly negative effect on muscle metabolism, mass, and function in middle-aged adults. Leucine supplementation may partially protect muscle health during relatively brief periods of physical inactivity. This trial was registered at
clinicaltrials.gov
as NCT00968344.
•Lower hippocampal activity predicted greater subjective cognitive decline (SCD)•Amyloid and actual memory decline are both predictors of SCD•Hippocampal activity predicted SCD independently of ...amyloid and actual decline•SCD in old adults appear to reflect their surprising insights into neural deficits.
We evaluated whether self-reports of worse cognition in older adults with normal cognitive function reflected actual memory decline, amyloid pathology, and subtle vulnerabilities in hippocampal function. We measured subjective cognitive decline (SCD) in 156 older participants from the Dallas Lifespan Brain Study. Functional hippocampal activation during encoding, measured with fMRI, and longitudinal memory change that was measured in the four years preceding the SCD measures were used to predict the magnitude of SCD. A subsample (N=105) also underwent 18F-Florbetapir PET imaging that measured amyloid burden. Results showed that increased SCD were associated with greater prior memory decline and amyloid deposition. Importantly, decreased hippocampal activation during encoding was a significant predictor of SCD, particularly in young-old adults below 69 years old, above and beyond prior memory change and amyloid deposition. These results indicate that multiple measures of neural and cognitive dysfunction are simultaneously associated with SCD. Moreover, SCD in younger seniors appears to reflect deficient hippocampal activity that increases their reports of poorer memory, independent of amyloid. This manuscript is part of the Special Issue entitled “Cognitive Neuroscience of Healthy and Pathological Aging” edited by Drs. M. N. Rajah, S. Belleville, and R. Cabeza. This article is part of the Virtual Special Issue titled COGNITIVE NEU-ROSCIENCE OF HEALTHY AND PATHOLOGICAL AGING. The full issue can be found on ScienceDirect at https://www.sciencedirect.com/journal/neurobiology-of-aging/special-issue/105379XPWJP.
Cognitive ageing research examines the cognitive abilities that are preserved and/or those that decline with advanced age. There is great individual variability in cognitive ageing trajectories. Some ...older adults show little decline in cognitive ability compared with young adults and are thus termed 'optimally ageing'. By contrast, others exhibit substantial cognitive decline and may develop dementia. Human neuroimaging research has led to a number of important advances in our understanding of the neural mechanisms underlying these two outcomes. However, interpreting the age-related changes and differences in brain structure, activation and functional connectivity that this research reveals is an ongoing challenge. Ambiguous terminology is a major source of difficulty in this venture. Three terms in particular - compensation, maintenance and reserve - have been used in a number of different ways, and researchers continue to disagree about the kinds of evidence or patterns of results that are required to interpret findings related to these concepts. As such inconsistencies can impede progress in both theoretical and empirical research, here, we aim to clarify and propose consensual definitions of these terms.
The challenges associated with the ageing population are important and continuous growth across the world, especially in Europe, the continent with the oldest population. The fundamental objective of ...active ageing interventions is to optimise opportunities for health, participation and security so as to increase the quality of life of the population with ageing. The Active Ageing Index is a flexible comparative analysis tool that has the mission to help promote and implement active ageing. Thus, the purpose of this paper is to analyse the phenomenon of active ageing from the perspective of the active ageing index in the European area. The methodology used consisted of document analysis, study for several countries in the European space such as: Italy, Germany, Poland, Spain, Romania, analysis and comparison of statistic data. The results obtained show that the role of this active ageing index is to capture the various facets of active ageing, measuring the contribution of older people (women and men) to economic and social life and to the extent to which the environment in which they live stimulates them in this regard to provide more active participation in employment, social life and to lead independent lives.
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