Author Interviews, Biomarkers, Brigham & Women's - Harvard, Diabetes, Endocrinology / 26.06.2023 Interview with: Dr. Bita Zahedi MD MA Endocrinologist Massachusetts General Hospital What is the background for this study? Response: The purpose of this study was to develop and validate a measure of dietary advanced glycation end-products (AGEs) to investigate the role of dietary AGEs in diabetic disease processes.  AGEs are a group of highly reactive compounds involved in the pathophysiology of diabetic complications, such as microvascular disease, cardiomyopathy, and possibly bone health. AGEs form through a nonenzymatic reaction between reducing sugars and free amino groups of proteins, lipids, and nucleic acids, also known as a Maillard or browning reaction. Endogenous AGE formation and accumulation is a normal part of metabolism and aging, however the process of glycation can be enhanced by hyperglycemia, hyperlipidemia, and increased oxidative stress. Additionally, AGEs can be absorbed from exogenous sources via consumption of various food items. Prior studies demonstrate that skin AGEs are predictive of Dietary AGEs (dAGEs) which are naturally present in certain uncooked foods, mainly animal-derived products, furthermore the method of food preparation can result in significant AGE formation. Considering the ubiquitous intake of dAGEs, it is possible that the consumption of exogenous AGEs contribute to AGE-induced oxidative stress, inflammation, and its subsequent detrimental sequalae. (more…)
Author Interviews, Endocrinology, Gender Differences, Weight Research / 16.06.2023 Interview with: Francesca Galbiati, MD Clinical/Research fellow in Endocrinology Massachusetts General Hospital What is the background for this study? Response:  Arginine-vasopressin (AVP) is a neurohormone well known for its role in water balance regulation. It promotes renal water absorption in the kidney, to maintain normal sodium levels in the blood via a tightly controlled osmotic regulation. Besides AVP classical role, data have shown that AVP effects extend beyond water balance regulation. Animal studies have shown that AVP has metabolic effects, including reducing food intake, inducing lipolysis, and promoting muscle regeneration in male mice. Furthermore, AVP is regulated differently in males and females, and affects cognition differently across sexes, a phenomenon called sexual dimorphism. However, it is unknown whether its dimorphism translates to metabolism. Also, findings on AVP metabolic role are inconsistent, possibly due to the opposing effects of AVP at different receptor subtypes, which regulation is still largely unknown. We performed this study to better investigate AVP metabolic role, and explore sex differences. We hypothesized that AVP would be positively associated with BMI, adiposity, and lean mass (acting as a signal of energy availability). We also predicted that relationships between AVP and body composition measures would differ by sex. We used the AVP area under the curve around a standardized meal to better capture repeated measures in response to food intake (that directly impacts energy availability). This also allowed to avoid the possible risk of fluctuating AVP levels due to possible pulsatile secretion. (more…)