Longevity and its regulation: centenarians and beyond

Longevity, Centenarians and Modified Cellular Proteodynamics

We have shown before that at least one intracellular proteolytic system seems to be at least as abundant in the peripheral blood lymphocytes of centenarians as in the same cells of young individuals (with the cells of the elderly population showing a significant dip compared to both young and centenarian cohorts). Despite scarce published data, in this review, we tried to answer the question how do different types of cells of longevous people-nonagenarians to (semi)supercentenarians-maintain the quality and quantity of their structural and functional proteins? Specifically, we asked if more robust proteodynamics participate in longevity. We hypothesized that at least some factors controlling the maintenance of cellular proteomes in centenarians will remain at the "young" level (just performing better than in the average elderly). In our quest, we considered multiple aspects of cellular protein maintenance (proteodynamics), including the quality of transcribed DNA, its epigenetic changes, fidelity and quantitative features of transcription of both mRNA and noncoding RNAs, the process of translation, posttranslational modifications leading to maturation and functionalization of nascent proteins, and, finally, multiple facets of the process of elimination of misfolded, aggregated, and otherwise dysfunctional proteins (autophagy). We also included the status of mitochondria, especially production of ATP necessary for protein synthesis and maintenance. We found that with the exception of the latter and of chaperone function, practically all of the considered aspects did show better performance in centenarians than in the average elderly, and most of them approached the levels/activities seen in the cells of young individuals.

The Less We Eat, the Longer We Live: Can Caloric Restriction Help Us Become Centenarians?

Striving for longevity is neither a recent human desire nor a novel scientific field. The first article on this topic was published in 1838, when the average human life expectancy was approximately 40 years. Although nowadays people on average live almost as twice as long, we still (and perhaps more than ever) look for new ways to extend our lifespan. During this seemingly endless journey of discovering efficient methods to prolong life, humans were enthusiastic regarding several approaches, one of which is caloric restriction (CR). Where does CR, initially considered universally beneficial for extending both lifespan and health span, stand today? Does a lifelong decrease in food consumption represent one of the secrets of centenarians’ long and healthy life? Do we still believe that if we eat less, we will live longer? This review aims to summarize the current literature on CR as a potential life-prolonging intervention in humans and discusses metabolic pathways that underlie this effect.

A Comparative Study on the Health Status and Behavioral Lifestyle of Centenarians and Non-centenarians in Zhejiang Province, China-A Cross-Sectional Study

Background: The growth rate of centenarians was unusually rapid in recent decades, ushering in an era of longevity. This study aims to explore the difference between centenarians and non-centenarians using quantitative research, and to scientifically guide residents to develop the correct lifestyle and health care ways. Methods: From October 2013 to August 2017. A cross-sectional survey was conducted on 271 centenarians and 570 non-centenarians by using a questionnaire to assess longevity and health issues which was developed for the needs of the study, who came from 29 counties and districts in 11 cities of Zhejiang province, China. Two hundred and fifty-five valid questionnaires were returned, with an effective response rate of 94.1%. Meanwhile, data of 526 non-centenarians from Zhejiang province was collected as a control group, with an effective response rate of 92.3%. Results: The prevalence rates of tumor, stomach and duodenal ulcer, diabetes, bronchial asthma, and chronic obstructive pulmonary disease, tuberculosis among centenarians were all lower than those among non-centenarians. The oral health of centenarians is better than that of non-centenarians. The consumption of coarse cereals, pasta, other staple foods and fruits among centenarians was higher than that of non-centenarians. The percentage of centenarians who smoke or engage in recreational activities every day was lower than that of non-centenarians. Conclusions: We should give full play to the role of preventive medicine and health management to safeguard the health of residents. Pay attention to oral health, and develop the good habit of loving teeth. The diet should be rich and varied, and increase the intake of grains and fruits. Give up smoking, limit alcohol, spirit-preserving with calming, follow the law of scientific regimen.

Multiregional Age-Associated Reduction of Brain Neuronal Reserve Without Association With Neurofibrillary Degeneration or β-Amyloidosis

Increase in human life expectancy has resulted in the rapid growth of the elderly population with minimal or no intellectual deterioration. The aim of this stereological study of 10 structures and 5 subdivisions with and without neurofibrillary degeneration in the brains of 28 individuals 25-102-years-old was to establish the pattern of age-associated neurodegeneration and neuronal loss in the brains of nondemented adults and elderly. The study revealed the absence of significant neuronal loss in 7 regions and topographically selective reduction of neuronal reserve over 77 years in 8 brain structures including the entorhinal cortex (EC) (-33.3%), the second layer of the EC (-54%), cornu Ammonis sector 1 (CA1) (-28.5%), amygdala, (-45.8%), thalamus (-40.5%), caudate nucleus (-35%), Purkinje cells (-48.3%), and neurons in the dentate nucleus (40.1%). A similar rate of neuronal loss in adults and elderly, without signs of accelerating neuronal loss in agers or super-agers, appears to indicate age-associated brain remodeling with significant reduction of neuronal reserve in 8 brain regions. Multivariate analysis demonstrates the absence of a significant association between neuronal loss and the severity of neurofibrillary degeneration and β-amyloidosis, and a similar rate of age-associated neuronal loss in structures with and without neurofibrillary degeneration.

Brain pathologies in extreme old age

With an emphasis on evolving concepts in the field, we evaluated neuropathologic data from very old research volunteers whose brain autopsies were performed at the University of Kentucky Alzheimer's Disease Center, incorporating data from the Georgia Centenarian Study (n = 49 cases included), Nun Study (n = 17), and University of Kentucky Alzheimer's Disease Center (n = 11) cohorts. Average age of death was 102.0 (range: 98-107) years overall. Alzheimer's disease pathology was not universal (62% with "moderate" or "frequent" neuritic amyloid plaque densities), whereas frontotemporal lobar degeneration was absent. By contrast, some hippocampal neurofibrillary tangles (including primary age-related tauopathy) were observed in every case. Lewy body pathology was seen in 16.9% of subjects and hippocampal sclerosis of aging in 20.8%. We describe anatomic distributions of pigment-laden macrophages, expanded Virchow-Robin spaces, and arteriolosclerosis among Georgia Centenarians. Moderate or severe arteriolosclerosis pathology, throughout the brain, was associated with both hippocampal sclerosis of aging pathology and an ABCC9 gene variant. These results provide fresh insights into the complex cerebral multimorbidity, and a novel genetic risk factor, at the far end of the human aging spectrum.

A preliminary candidate approach identifies the combination of chemerin, fetuin-A, and fibroblast growth factors 19 and 21 as a potential biomarker panel of successful aging

Although the number of centenarians is growing worldwide, the potential factors influencing the aging process remain only partially elucidated. Researchers are increasingly focusing toward biomarkers as tools to shed more light on the pathophysiology of complex phenotypes, including the ability to reach successful aging, i.e., free of major chronic diseases. We therefore conducted a case-control study examining the potential associations of multiple candidate biomarkers in healthy centenarians and sex-matched healthy elderly controls. Using a case-control study of 81 centenarians (aged ≥ 100 years) selected based on the fact that they were disease-free and 46 healthy elderly controls (aged 70-80 years), serum levels of 15 different candidate biomarkers involved in the regulation of metabolism, angiogenesis, inflammation, and bone formation were measured. Of the 15 biomarkers tested, four molecules (chemerin, fetuin-A, and fibroblast growth factors [FGF] 19 and 21) were found to be independently associated with successful aging regardless of sex. Logistic regression analysis confirmed that chemerin, fetuin-A, FGF19, and FGF21 were independently associated with successful aging [predicted probability (PP) = 1 / [1 + 1 / exp (11.832 - 0.027 × (chemerin) - 0.009 × (fetuin-A) + 0.014 × (FGF19) - 0.007 × (FGF21)]. The area under the curve (AUC) of predicted probability values for the four-biomarker panel revealed that it can discriminate between centenarians and elderly controls with excellent accuracy (AUC > 0.94, P < 0.001). Although preliminary in essence and limited by the low sample size and lack of replication in other independent cohorts, our data suggest an independent association between successful aging and serum chemerin, fetuin-A, FGF19, and FGF21, which may provide novel information on the mechanisms behind the human aging process. Whether the four-biomarker panel may predict successful aging deserves further scrutiny.