How Metformin Does Its Job

Animal studies into the elusive mechanism behind the vascular protective effects of metformin suggest its efficacy stems from blunting thioredoxin-interacting protein promoter (TXNIP) overexpression, researchers said.

Such overexpression can result in poor glycemic control and endothelial dysfunction, according to Yun Yan, MD, and Mark A. Clements, MD, division of endocrinology, department of pediatrics, of Children's Mercy Hospital and University of Missouri-Kansas City, and colleagues, who reported their findings in Molecular Endocrinology.

Metformin, which is well known for its lipid-lowering and insulin sensitivity-improving actions in liver and pancreatic cells, has been considered a potential adjunctive therapy in treating poorly controlled type 1 diabetes (T1D) with obesity and insulin resistance. However, noted Yan and Clements, the underlying mechanism by which metformin improves insulin sensitivity and promotes its vascular protective effects remains obscure.