Prolonging the lifespan of humans considerably still remains a distant dream. Researchers say that we need to look closely at nature to find ways of increasing human longevity. Present methods allow increasing the lifespan of animal models by 10-20% only. However, now researchers have found that an anti-insulin protein called Imp-L2 may increase the lifespan of ants by as much as 500%. Humans have long sought the key to longevity, if not immortality. Of course, human life expectancy has almost doubled in the last century due to better healthcare and disease prevention including diabetic neuropathy treatment. However, we are still far from revolutionary achievements like slowing down aging and increasing the average lifespan multiple times.
One of the ways of understanding aging and finding ways of longevity is by looking at nature. For example, one may study animal species that live much longer than humans. However, that is of little help as those animals have a very different kinds of metabolism. Another, perhaps more practical, way of finding a key to longevity is looking at species where some can live much longer than others. Just take the example of garden ants. In these ants, a queen can live for as long as 30 years, while workers barely live for 2-3 years, though both share similar genes. Ants are unique in many ways. In the animal kingdom, bearing many offspring generally reduces lifespan. It is a cost one has to pay for higher fertility. Bearing offspring require the allocation of many nutritional and metabolic resources.
However, ants differ from other species. In ants, a queen ant lays millions of eggs in its lifespan, and yet it can live ten or more times longer than worker ants. It means that the queen ant may have some unique way of prolonging life. Science has found that it has to do with insulin pathways. Insulin is not just needed for glucose metabolism; it plays an important role in many other metabolic pathways. It appears that high insulin level is associated with faster aging. It seems that blocking specific insulin pathways may prolong life, including pancreatic pain treatment. This ability to block certain insulin pathways ensures much longer survival of queen ant.
However, there is one problem in studying the queen ant. Although it may be genetically similar to workers, the queen is born that way. As a result, it is born to live longer than worker ants. However, researchers have made an exciting finding. An ant species called Harpegnathos saltator, which is native to India, has some uniqueness about it. In these ants, if the queen dies, one of the worker ants can fight its way to become a queen ant. What is unbelievable here is that once any worker ant becomes queen and starts laying eggs, its lifespan increases significantly. Thus, workers live for merely seven months in this ant species, and the queen can live for four years.
It means that the Harpegnathos saltator is ideal for finding the key to longevity. Researchers have to just identify the biochemical changes that occur in the ant after it becomes the queen. Then, if they can find those chemicals responsible for longevity, they might even be able to increase human lifespan. It appears that researchers have found the secret to longevity in these pseudoqueens. It seems that though egg-laying results in increased insulin production in these pseudoqueens, they can counter its ill effects. They produce an insulin-suppressing protein called Imp-L2. This protein can block certain insulin effects, thus blocking the pathways associated with aging and shorter lifespan.
Researchers say that to prolong the life of humans significantly, it is vital to find the right kind of model system. For example, by manipulating various factors, science can prolong the life of mice or flies by just 10-20%. However, in ants, life can be extended by 500%. So now it is time to understand how these findings may help increase the longevity of mammals.