Combining the circulatory systems of old and young mice has provided evidence that aging begins when the body receives a command to self-destruct.

Researchers who study life extension are interested in the causes of senescence.

“Some believe that this is a natural process, caused by accumulation of wastes of vital functions and by insult to cells due to environmental influence. Others assume that self-repairing and self-purification capabilities of a human organism are quite high and are far from exhausted within the 85 years assigned for a life of an individual,” says Gennady Boutenko, a member of the Russian Academy of Medical Sciences. “It means that at some point, a command is turned on to slow down the recovery process, and this is when the old age begins.”
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