Dr. Carmela Abraham, a professor of biochemistry and medicine at Boston University School of Medicine (BUSM) and her colleagues observed that the levels of Klotho in the brain showed a prominent decline with aging.
They found that that insulin, a hormone usually associated with diabetes, increases the levels of secreted Klotho.
They propose that Klotho could become the next "fountain of youth" if further researches are conducted to increase its level to those levels found in young individuals.
The link between Klotho and aging prompted Abraham's group to examine the regulation of Klotho further.
The Klotho protein sits in the membrane of certain cells but is also found circulating in serum and cerebrospinal fluid, which indicates that it is secreted. The fact that Klotho is secreted suggested that enzymes that act like scissors must be involved in the liberation of Klotho from the cell membrane.
Dr. Ci-Di Chen, an assistant professor working in Dr. Abraham's group, then sought to discover the enzymes responsible for Klotho release and also investigated other factors that may affect the release of active Klotho.
They found that insulin increases significantly the levels of secreted Klotho.
According to the team, the reason this finding is important is because surplus insulin has been previously implicated in a biochemical pathway that is associated with a decreased life span and elevated oxidative stress.
In addition, they add, this observation provides a potentially crucial link between Klotho and sugar metabolism, and raises an interesting relationship between Klotho and type II diabetes, commonly known as late onset diabetes.
The authors are proposing a novel mechanism of action for Klotho whereby insulin increases Klotho secretion, i.e., activity, and in turn, the secreted Klotho inhibits insulin's actions in the cell, which are known to be detrimental when insulin is in excess.
Following these findings, the Abraham laboratory is now studying various ways to increase the level of Klotho to those levels found in young individuals.
"The findings reported here may lead to new research designed to regulate the aging process, in other words, compounds that would increase Klotho could become the next "fountain of youth," said Abraham.