Pioglitazone Prevents Capillary Rarefaction in Streptozotocin-Diabetic Rats Independently of Glucose Control and Vascular Endothelial Growth Factor Expression

glucose, left ventricular weight, or body weight but nearly doubled absolute and relative capillary densities compared to untreated controls (1.2 vs. 0.6 capillaries/myocyte in heart and 1.5 vs. 0.9 capillaries/myocyte in quadriceps muscle) af-ter 13 weeks of diabetes. No antiapoptotic or angiogenic in-fluence of pioglitazone was detected while a reduced ex-pression of hypoxia-inducible factor-3 and PPAR coactiva-tor-1 (PGC-1 ) mRNA as well as vascular endothelial growth factor (VEGF) protein possibly occurred as a consequence of improved vascularization. Conclusion: Pioglitazone pre-serves microvascular structure in diabetes independently of improvements in glycemic control and by a mechanism un-related to VEGF-mediated angiogenesis. Copyright © 2012 S. Karger AG, Base