Diet-Induced weight loss improves vascular insulin sensitivity in patients with type 2 diabetes

Abstract

Background: Insulin-stimulated blood flow plays a key role in glucose and insulin delivery to target tissues, such as skeletal muscle. With the development of obesity and type 2 diabetes (T2D), there are impairments in vascular insulin signaling and, consequently, blunting of insulin-induced vasodilation. However, it remains unknown if diet-induced weight loss attenuates vascular insulin resistance in both men and women with T2D. Methods: Nine women (aged 61.9±2.8 yrs; BMI 36.1±1.8) and seven men (aged 54.9±6.0 yrs; BMI 37.6±2.6) with T2D were recruited to undergo a six-month diet to induce weight loss by reducing sugar intake to <5% of energy and total daily energy intake by 500 kilocalories. Anthropometrics, superficial femoral artery blood flow and skeletal muscle perfusion responses to systemic insulin infusion, brachial artery flow-mediated dilation (FMD), carotid-to-femoral pulse wave velocity (PWV), and biochemical parameters were assessed at baseline and at the end of the six-month dietary intervention. Dietary records were analyzed using Nutrition Data System for Research software. Results: The low-energy diet was effective at reducing body weight, as well as other metabolic outcomes including markers of liver function and inflammation. These improvements were accompanied with an increase in FMD, but not a reduction in PWV. Lastly, leg blood flow and skeletal muscle perfusion responses to insulin infusion were enhanced following the dietary intervention, an effect primarily driven by women. Conclusions: Our results indicate that diet-induced weight loss enhances vascular insulin sensitivity in patients with T2D and that these effects are primarily observed in women. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.