Vascular protective effects of diabetes medications that mimic or increase glucagon-like peptide-1 activity

The incidence of type 2 diabetes (T2DM) is increasing rapidly worldwide and is a strong risk factor for cardiovascular disease (CVD) events. Although hyperglycemia is associated with increased CVD, intensive glycemic control with current diabetes medications has failed in recent large clinical trials to reduce macrovascular disease, demonstrating that intensive glucose control alone is insufficient to reduce major CVD events. A new approach to lowering glucose takes advantage of the incretin system and medications that raise or mimic glucagon-like peptide-1 (GLP-1). These agents not only improve glycemic control by mechanisms that minimize hypoglycemia, but also improve lipoprotein profiles, blood pressure control and weight loss. There is also increasing evidence that at least pharmacologic concentrations of GLP-1 or GLP-1 mimetics may improve endothelial function and have direct vascular-protective effects. Importantly, these benefits transpired even before the improvements in weight and overall glucose control occurred. It remains to be seen whether the chronic effects of GLP-1 activity on glucose, CVD risk factors and vascular function will lead to lasting beneficial effects on CVD risk. If preliminary findings on the vasculoprotective effects of GLP-1 agents are validated and confirmed in longitudinal clinical trials, this class of drugs may represent a paradigm shift in the treatment of vascular disease in both patients with diabetes and in non-diabetic individuals at high risk for CVD. Recent patents regarding GLP-1 agents are discussed in this review article.