Background: Endothelial dysfunction and postprandial hyperglycemia represent independent risk factors for cardiovascular diseases. Obesity is connected with endothelial impairments; however, it is unclear whether weight loss can modify endothelial function during the postprandial period. The aim of this study was to evaluate endothelial response (post-ischemic forearm blood flow, PIFBF) in a fasted state and following ingestion of 75g glucose before and after very low caloric diet (VLCD).
Material/Methods: 40 obese premenopausal women (age 39.6±7.8 years, BMI 34.3±3.2 kg/m2) participated in 4-week very low caloric diet (VLCD, 800kcal/day). Before and after VLCD, the baseline blood flow and PIFBF were measured using a mercury strain gauge plethysmography in fasting state as well as 1 hour after ingestion of 75 g glucose.
Results: Dietary intervention resulted in a 7% weight loss (p<0.05) and a decrease in insulin resistance index HOMA-IR (2.44±1.25 vs. 1.66±0.81, p<0.05). Before VLCD intervention, PIFBF following oral glucose challenge decreased by 8.2±9.1 ml/min/100 g tissue, while after weight loss identical stimulus increased PIFBF by 4.2±8.9 ml/min/100 g tissue (p<0.05). Plasma ICAM-1 and VCAM-1 decreased by 8% and 10%, respectively, throughout the study.
Conclusions: Postprandial endothelial dysfunction is ameliorated following weight loss in obese women. This finding demonstrates the beneficial effects of weight reduction on atherosclerosis risk.

Keywords: Obesity - physiopathology, Plethysmography, Linear Models, Forearm - blood supply, Endothelium, Vascular - physiopathology, Caloric Restriction, Blood Glucose, Anthropometry, Postprandial Period - physiology, Premenopause - physiology, Regional Blood Flow - physiology, Weight Loss - physiology