Scientists from UT Southwestern Medical Center have elucidated the mechanism of a recently identified klotho gene, a probable “aging-suppressor” gene:
Researchers at UT Southwestern Medical Center have discovered that a protein prolonging life in mice works by controlling insulin.
The protein, Klotho, is found in several species. In mice, the researchers discovered, it acts as a hormone, circulating through the blood and binding to cells.
Therapies based on this hormone could prove to be a way to extend life or slow its effects, said Dr. Makoto Kuro-o, assistant professor of pathology and senior author of the study published in today’s online issue of Science Express and appearing in an upcoming issue of Science. “It could be one of the significant steps for developing anti-aging therapy…”
The researchers were especially interested in how the hormone affected insulin, because making an animal resistant to insulin increases its lifespan – a phenomenon found in animals ranging from worms to fruit flies to mice.
The mice with higher levels of Klotho had more insulin in their system than the normal mice, suggesting that the Klotho mice were resistant to insulin; they had to make more of it to make up for the resistance. The opposite was true with the mice deficient in Klotho. They were more sensitive to insulin and had reduced levels of it.
The influence on insulin creates a problem for Klotho should it be used as a therapy against aging: It may extend life, but it could also make an animal diabetic.
Mice with the excessive Klotho also had fewer offspring than normal mice, said Dr. Kuro-o, a Southwestern Medical Foundation Scholar in Biomedical Research.