AGEs Inducing EPCs Apoptosis via ROS and p38 MAPK/JNK Pathways in Diabetic Vascular Complications.

Abstract

Endothelial progenitor cells (EPCs) promote blood-vessel repair, but their apoptosis worsens diabetes-related vascular damage. Although advanced glycation end products (AGEs) abound in diabetes, it remains unclear whether they trigger EPC apoptosis through oxidative stress and driven MAPK activation. EPCs were extracted from Sprague-Dawley rats' bone marrow. Cells were treated with varying AGEs concentrations (50, 100, 200 µg/mL) and durations (6, 12, 24, 48 hours). Apoptosis was measured via Annexin V/PI staining flow cytometry, and protein expression of Bax (pro-apoptotic) and Bcl-2 (anti-apoptotic) was analyzed by Western blot. Reactive oxygen species (ROS) levels were detected by flow cytometry using DCFH-DA molecular probes. The effects of antioxidants (NAC) and specific inhibitors (SP600125 for JNK and SB203580 for p38MAPK) on apoptosis and protein expression were also examined. EPC apoptosis increased with AGEs concentration and exposure time, peaking at 24 hours. Bax expression rose, while Bcl-2 decreased with higher AGEs levels and prolonged exposure. ROS generation increased up to 12 hours before declining. Antioxidant NAC reduced ROS and Bax expression. Inhibitors SP600125 and SB203580 decreased JNK and p38MAPK activation, lowered Bax, and increased Bcl-2 expression.