Current Aging Science - Volume 8, Issue 1, 2015

In contraposition to the view of aging as a stochastic time-dependent accumulation of damage, phenoptotic theories of aging postulate that senescence may provide supra-individual advantages, and therefore it might have been promoted by natural selection. We reason that although programmed aging theories are subjectively appealing because they convey a cure for aging, they also raise a number of objections tha Read More

There is increasing evidence that nutritional and hormonal signals during development can influence longevity. It was reported that mice subjected to mild calorie restriction only during the preweaning period live longer than control animals. In long-lived hypopituitary dwarf mice, longevity can be reduced by growth hormone replacement therapy during pre- and peri-pubertal period. These findings suggest that trajectory of agi Read More

The longstanding debate about whether aging may have evolved for some adaptive reason is generally considered to pit evolutionary theory against empirical observations consistent with aging as a programmed aspect of organismal biology, in particular conserved aging genes. Here I argue that the empirical evidence on aging mechanisms does not support a view of aging as a programmed phenomenon, but rather su Read More

In the 60 years since Medawar questioned the assumption that aging is a selected trait with a fitness benefit, mainstream biogerontology has overwhelmingly adopted the view that aging is a product of evolutionary neglect rather than evolutionary intent. Recently, however, this question has come to merit further scrutiny, for three reasons: a variety of new ways in which aging could indeed be “programmed” have been p Read More

For more than 150 years there has been some level of scientific argument regarding whether aging in humans and other mammals is purposely genetically programmed because living too long produces an evolutionary disadvantage, or whether aging in mammals is non-programmed because there is no such disadvantage. Although for many decades it was very widely thought that programmed aging in mammals was Read More

There are two modern evolutionary theories of mammal senescence: Programmed theories contend that mammals purposely limit their lifespans because doing so creates an evolutionary advantage. Non-programmed theories contend that each mammal specie only needs a particular lifespan and therefore only evolved and retained the capability for attaining that lifespan. Arguments over the evolutionary nature of agi Read More

The modern synthesis or evolutionary theory of aging assumes that aging results from the accumulation of errors or damages at the cellular level through the inadequacies of an organism's repair and maintenance machinery. The demonstration of cellular and organic rejuvenation requires the hypothesis that aging is the result of irreparable damage to be rejected. I will propose basic principles of mammalian aging based only o Read More

There are two opposite paradigms to explain aging, here precisely defined as “age-related progressive mortality increase, i.e. fitness decline, in the wild”. The first maintains that natural selection is unable to maintain fitness as age increases. The second asserts that, in particular ecological conditions, natural selection favors specific mechanisms for limiting the lifespan. The predictions derived from the two paradigms are qu Read More

Aging is now viewed as programmed under genetic control by a growing minority of evolutionary biologists, and a larger proportion of researchers in gerontology. The hypothesis of programmed aging has been regarded as encouraging for anti-aging science. Some mechanisms of programmed aging may present ready targets for medical interference [mitigation alleviation attenuation], while other kinds of programmed mechan Read More

It is supposed that the development and aging of multicellular animals and humans are controlled by a special form of the clock mechanism - a chronograph. The development of animals and their aging are interconnected by the program of the species lifespan that has been selected in the evolution of each species to fit the resources of its ecological niche. The theory is based on the idea about a controlled loss by the neuro Read More

Ageing is generally viewed as a detrimental phenotype; with age comes increasing susceptibility to disease and frailty. Recent data also suggests that disease can result in an increase in ageing phenotypes suggesting a positive feedback loop. It is clear that lifespan can be modified genetically and by interventions in certain organisms but the mechanisms by which this is achieved have not yet been fully elucidated, as indeed is t Read More

During the last decade, several pieces of convincing evidence were published indicating that aging of living organisms is programmed, being a particular case of programmed death of organism (phenoptosis). Among them, the following observations can be mentioned. (1) Species were described that show negligible aging. In mammals, the naked mole rat is the most impressive example. This is a rodent of mouse size liv Read More

During the last decade, our understanding of the molecular mechanisms regulating the cellular environment has made significant advances. With the new dynamical description of the functionalities of the cell, several processes known to play a crucial role in the onset of aging such as cell senescence, the increase of ROS level and telomere shortening appear to be a consequence of the disruption of a systemic dynamical e Read More