Metoprolol rescues endothelial progenitor cell dysfunction in diabetes

Area of Science:

• Cardiovascular Pharmacology
• Endothelial Biology
• Diabetes Complications

Background:

• Diabetes and hypertension amplify endothelial dysfunction, increasing cardiovascular risk.
• Beta-blockers are standard cardiovascular treatments, but their effect on endothelial progenitor cells (EPCs) in diabetes is unclear.

Purpose of the Study:

• To investigate the impact of five beta-blockers on EPC function in diabetes.
• To evaluate metoprolol's efficacy in preclinical diabetic models and human subjects.

Main Methods:

• In vitro screening of five beta-blockers (metoprolol, atenolol, propranolol, bisoprolol, nebivolol) on EPC function.
• In vivo studies in STZ-induced diabetic mice assessing EPC function, wound healing, and angiogenesis.
• Clinical evaluation using Reactive Hyperemia Peripheral Arterial Tonometry (RH-PAT) in diabetic patients.

Main Results:

• Metoprolol uniquely improved EPC function in vitro (tube formation, migration).
• In diabetic mice, metoprolol restored EPC migration, increased circulating EPCs, accelerated wound healing, and promoted angiogenesis.
• Metoprolol enhanced eNOS phosphorylation and reduced superoxide levels in diabetic EPCs.
• Clinical trials showed higher RH-PAT index in metoprolol-treated versus bisoprolol-treated diabetic patients.

Conclusions:

• Metoprolol demonstrates superior efficacy in improving EPC function compared to other tested beta-blockers.
• Metoprolol treatment accelerates wound healing and improves endothelial function in diabetic subjects, likely via enhanced EPC function.