Hypothesis: lifespan is regulated by chronomere DNA of the hypothalamus

Alexey Olovnikov: theoretical biology beyond the margins

Alexey Olovnikov (1936-2022) is an author of the famous marginotomy hypothesis, where he recognized the DNA end replication problem and its role in cell aging. In this biographical note we celebrate the 50th anniversary of this theoretical discovery that later enjoyed a brilliant confirmation and gave rise to a new thriving field of molecular biology and gerontology. We also take a look at the evolution of ideas in Alexey Olovnikov's lifelong quest to uncover the molecular mechanisms of aging, exploring the reasons why he walked away from his initial conclusion about the key role of telomeres in aging, and built a new vast theoretical landscape that linked all stages of ontogenesis.

"If I Were in Nature's Place, I Would Do It Like This..." Life and Hypotheses of Alexey Olovnikov

In this article, we commemorate the life and scientific journey of the brilliant gerontologist-theorist Alexey Olovnikov (1936-2022). In 1971, he published his famous "marginotomy" hypothesis, in which he predicted the replicative shortening of telomeres and its role as a counter of cell divisions and biological age of an organism. This work put forth several remarkable assumptions, including the existence of telomerase, which were confirmed two decades later. Despite this, Alexey Olovnikov moved further in his theoretical studies of aging and proposed a series of new hypotheses that seem no less exotic than the marginotomy hypothesis once appeared. Alexey Olovnikov had an extraordinary way of looking at biological problems and, in addition to aging, authored striking concepts about development, biorhythms, and evolution.

Telomerase and telomeres in aging theory and chronographic aging theory (Review)

The current review focuses on the connection of telomerase and telomeres with aging. In this review, we describe the changes in telomerase and telomere length (TEL) during development, their role in carcinogenesis processes, and the consequences of reduced telomerase activity. More specifically, the connection of TEL in peripheral blood cells with the development of aging‑associated diseases is discussed. The review provides systematic data on the role of telomerase in mitochondria, the biology of telomeres in stem cells, as well as the consequences of the forced expression of telomerase (telomerization) in human cells. Additionally, it presents the effects of chronic stress exposure on telomerase activity, the effect of TEL on fertility, and the effect of nutraceutical supplements on TEL. Finally, a comparative review of the chronographic theory of aging, presented by Olovnikov is provided based on currently available scientific research on telomere, telomerase activity, and the nature of aging by multicellular organisms.

Pineal gland as an endocrine gravitational lunasensor: manifestation of moon-phase dependent morphological changes in mice

We found that some morphological properties of the pineal gland and submandibular salivary gland of mice are significantly distinct at the new and full moon. We suppose that the differences are initiated by the displacements of the electron-dense concretions in the secretory vesicles of pinealocytes. This presumably occurs under the influence of the gravitational field, which periodically changes during different phases of the moon. It seems that the pinealocyte is both an endocrine and gravisensory cell. A periodic secretion of the pineal gland probably stimulates, in a lunaphasic mode, the neuroendocrine system that, in turn, periodically exerts influence on different organs of the body. The observed effect probably serves, within the lifelong clock of a brain, to control development and aging in time.

Alzheimer's disease is not "brain aging": neuropathological, genetic, and epidemiological human studies

Human studies are reviewed concerning whether "aging"-related mechanisms contribute to Alzheimer's disease (AD) pathogenesis. AD is defined by specific neuropathology: neuritic amyloid plaques and neocortical neurofibrillary tangles. AD pathology is driven by genetic factors related not to aging per se, but instead to the amyloid precursor protein (APP). In contrast to genes involved in APP-related mechanisms, there is no firm connection between genes implicated in human "accelerated aging" diseases (progerias) and AD. The epidemiology of AD in advanced age is highly relevant but deceptively challenging to address given the low autopsy rates in most countries. In extreme old age, brain diseases other than AD approximate AD prevalence while the impact of AD pathology appears to peak by age 95 and decline thereafter. Many distinct brain diseases other than AD afflict older human brains and contribute to cognitive impairment. Additional prevalent pathologies include cerebrovascular disease and hippocampal sclerosis, both high-morbidity brain diseases that appear to peak in incidence later than AD chronologically. Because of these common brain diseases of extreme old age, the epidemiology differs between clinical "dementia" and the subset of dementia cases with AD pathology. Additional aging-associated mechanisms for cognitive decline such as diabetes and synapse loss have been linked to AD and these hypotheses are discussed. Criteria are proposed to define an "aging-linked" disease, and AD fails all of these criteria. In conclusion, it may be most fruitful to focus attention on specific pathways involved in AD rather than attributing it to an inevitable consequence of aging.

Biogerontology in Russia: from past to future

The paper presents major steps of gerontology development in Russia. The issues of training in gerontology and geriatrics, institutional infrastructure within the Gerontological Society of the Russian Academy of Sciences and its activities have been considered therein. Some results of Russian researchers obtained during 2005-2010 have been summarized as well. Special attention is given to the prospects of gerontology in Russia.