Metformin restores prohormone processing enzymes and normalizes aberrations in secretion of proinsulin and insulin in palmitate-exposed human islets.

Metformin normalized proinsulin and insulin secretion after prolonged nutrient-overstimulation, coupled with normalization of the converting enzymes, in isolated islets. In adolescents with obesity, metformin treatment was associated with improved PI/I, which was coupled with improved glycaemic control.