Researchers at Yeshiva University's Albert Einstein College of Medicine and at the University of California-Los Angeles said their study, which focused on diabetic rodents, is the first to show a role in glucose metabolism for humanin, a small peptide that previous studies suggest might protect nerve cells from death associated with Alzheimer's and other brain diseases.
"This new role of humanin in glucose metabolism … is very intriguing since scientists have long proposed a link between type 2 diabetes and Alzheimer's disease," said Professor Nir Barzilai, a co-senior author of the study and director of the Institute for Aging Research at Einstein.
In the study, the scientists infused humanin into the brains of diabetic rats. The researchers said the infused humanin significantly improved overall insulin sensitivity, and a single treatment with a highly-potent form of humanin significantly lowered blood-sugar levels in the diabetic rats.
"The improvement in insulin sensitivity caused by centrally administered humanin may be one of the main mechanisms through which humanin regulates cell survival," Barzilai said. "This may provide another potential mechanism by which humanin protects against Alzheimer's disease."
The research appears in the online journal PLoS One.