Programmed Longevity Theory OR "The Program of Longevity"

Author:

A group of researches: G. Lithgow, S. Murakami, T. Johnson; L. Guarente, C. Kenyon, v. Longo et al.

History:

This theory is as it were the theory of anti-aging. It explains when longevity may emerge in the process of evolution. The theory has been developing since 1990s.

Example:

Under stress, the organism enters the «waiting mode». In this mode, the organism saves its resources suppressing biosynthesis of structural proteins, switching the household genes off, holding the growth and reproduction up. Besides, the organism delays the entry into the reproduction cycle and increases its stress resistance (it means that the organism activates its antioxidant systems, induces heat-shock proteins, DNA repair and autophagy-related enzymes). Measures of economy and increasing of the stress resistance help the organism overcome spontaneous injuries. That delays the aging of the whole organism.

Description of the Theory:

According to this theory, the program of longevity might appear in evolution to overcome short-time extreme environmental conditions (overheating, supercooling, decrease of caloric value of food). This program allows the organism to exceed its normal life span by entering the «maintenance mode». The fact is that survival rate of descendants will be extremely low under short-time negative environmental conditions so it is profitable to an organism to direct its resources to waiting and delay reproduction. In the «maintenance mode» cell growth and divisions as well as reproduction pause but stress resistance increases. So we can say about the peculiar cross adaptation.

Molecular and cellular mechanisms of stress resistance turning on in the «maintenance mode» can afterwards help to overcome another sorts of stress (e.g. negative effects of radiation). The same mechanisms withstand the age-related accumulation of damages causing aging.
Mutations are currently known which increase the life span in experimental animal. Individuals with such mutations get into the «maintenance mode» irrespective of the environmental conditions.

Additions and Сriticism:

While the mutation accumulation and the disposable soma theories of aging rest upon permanent pressure of the environmental conditions (predators, diseases), the program of longevity could arise in evolution for overcoming the short-time extreme environmental conditions.

The programmed longevity theory predicts that if an individual undergoes moderate stress (overheating, supercooling, decrease of caloric value of food) at the early stages of its life, this individual will live longer. However, this assumption needs careful examination in experiments. Nevertheless, it is established that low-calorie diet (30–40% decrease in volume of food without underfeeding) increases the lifespan and delays aging in yeasts, worms, mice, rats and primates.

Publications:

• Kahn, Arnold, and Anders Olsen. «Stress to the rescue: Is hormesis a ‘cure’for aging?." Dose-Response 8.1 (2010): dose-response.
• Gems, David, and Linda Partridge. «Stress-response hormesis and aging: «that which does not kill us makes us stronger»." Cell metabolism 7.3 (2008): 200–203.
• Murakami, Shin, and Thomas E. Johnson. «A genetic pathway conferring life extension and resistance to UV stress in Caenorhabditis elegans." Genetics 143.3 (1996): 1207–1218.
• Guarente, Leonard, and Cynthia Kenyon. «Genetic pathways that regulate ageing in model organisms." Nature 408.6809 (2000): 255–262.