In some animal species, presence of large offspring is associated with a decrease in life expectancy. This is mainly due to the fact that fauna representatives producing more offspring dispense their nutritional resources to support regeneration processes. It’s revealed insulin-similar factors and insulin production underlie anti-correlation between life shortening and species rebirth.
Nevertheless, last experiments have shown this link is absent in ants. Rather, on the contrary, for these insects, it is the laying of eggs that correlates with long life. It has been proven that the metabolism of ant queens works at the highest level in order to ensure regeneration without accelerating aging.
Centerpiece of such mechanism may be protein suppressing insulin. Ants release antiinsulin proteins, which becomes a blocker for segments of insulin path being in charge of aging mechanisms. As studies demonstrate, in organisms of queens, there’s the dual control of insulin producing – hormone directly involved in providing a natural “compromise” between life duration and giving of offspring. Particularly, during egg growth, level of insulin is essentially increased, whilst female ovaries release insulin blockers: it makes senescence slower.
Research’s results were announced in Science. Hua Yang, famous biologist, claimed the discovery holds the key to comprehending the aging in many animal species.
In ants, reproductive functions are assigned to queens. In certain species, ability of worker ants to move to another caste and also perform a reproductive function is seen. Moreover, despite that from birth these insects belonged to, say, the working class, their life expectancy becomes approximately five times longer. This process also works in reverse: if the royals are placed in a working environment, they will work on an equal basis with representatives of this caste – their lives will be reduced several times. How exactly these processes are regulated is still not exactly clear.
According to Professor Yang, there is a natural signaling system in the body of ants resistant to insulin dampening insulin action at time of laying eggs and developing offspring. Therefore, high reproduction isn’t a catalyst for aging processes for these insects. To estimate connections between regeneration and life endurance, a team of scientists led by Mr. Yang conducted RNA sequencing of tissues of worker and dominant insects.
The essence of the study was to compare gene behavior in caste changes. It’s revealed insulin in gamergate increased: it was necessary to stimulate oogenesis. Nevertheless, it didn’t lead to a catastrophic decrease in life expectancy. Scientists supposed part of insulin path was blocked by Imp-L2 substance: it allowed these individuals to live longer.
Thereby, Imp-L2 is activated in some cases and slows elements of insulin action catalyzing aging. Imp-L2 does not affect insulin path segment being in charge of stimulating reproduction.
Another significant moment for scientists is if mammals, incl. us, could also get advantages from insulin blocking in future. So far, studies have only been conducted in certain species of insects, which already allows scientists to understand some of the mechanisms of insulin’s influence on reproductive mechanisms and longevity.