New approach lowers blood sugar in both type 1 and type 2 diabetes, say US researchers

Researchers at the Children's Hospital Boston in the USA have discovered a mechanism for normalizing blood sugar that does not involve insulin and could offer a new therapeutic approach to both kinds of diabetes.

Reporting in Nature Medicine online on February 13, Umut Ozcan and colleagues in the Children's Division of Endocrinology show that a regulatory protein called XBP-1s, when activated artificially in the liver, can normalize high blood sugar in both lean, insulin-deficient type 1 diabetic mice and obese, insulin-resistant type 2 diabetic mice. This suggests that approaches aimed at increasing XBP-1s activity may benefit patients with either type of diabetes.

In previous work, Dr Ozcan's lab identified XBP-1s as a key to the body's sensitivity to insulin, and shown that its function is impaired in the presence of obesity. Initially, XBP-1s was thought to increase insulin sensitivity and normalize blood glucose by binding to DNA and relieving stress on the endoplasmic reticulum, a cellular organ that assembles and folds proteins. When XBP-1s was artificially activated, "blood sugars in obese mice with type 2 diabetes came down abruptly," Dr Ozcan says.