Evaluation of the addition of ingredients in coffee beverages on the glycemic index and glycemic load in vivo and its relationship with glucose uptake in Caco-2 cells

Abstract

Diabetes Mellitus (DM) is an important chronic disease and a growing public health problem, with its incidence associated with factors such as urbanization, epidemiological and nutritional transition, sedentary lifestyle, overweight, and population aging. Changes in lifestyle such as physical activity and health eating habits contribute to the reduction of glycaemia and diabetes control. As such, coffee is a widely consumed food rich in phenolic compounds with antioxidant properties, and clinical studies suggest that higher coffee consumption may be associated with a lower risk of mortality and cardiovascular disease in DM. Studies on the glycemic index (GI) of foods are of great relevance, as they are related to possible physiological and therapeutical effects of low GI diets, both for health people and those with DM. The coffee beverage is the second most consumed in the world, however, there are few studies regarding the addition of ingredients in the beverage and the effects of its components on glucose metabolism. Therefore, it is interesting to investigate the impact of phenolic compounds and added ingredients in coffee beverages on carbohydrate digestion and absorption. Objectives: To evaluate the glycemic index and glycemic load in healthy individuals and the mechanism of action of coffee beverages in modulating genes related to glucose uptake in intestinal Caco-2 cells, and to verify the ability of these beverages in inhibiting the enzymes ±-amylase, ±-glucose, and DPP-IV. Methods: Coffee samples and ingredients will be purchased from local retailers. The beverages will undergo in vitro digestion and the phenolic compounds will be quantified and identified. Assays of glucose permeation and quantification in Caco-2 cells; assays of ±-glucosidase, ±-amylase, and DPP-IV inhibition; and gene expression and protein content of glucose transporters (SGLT1 and GLUT2) in Caco-2 intestinal cells will be performed. The glycemic index and glycemic load will be evaluated in healthy coffee drinkers. Expected results: We aim to verify whether coffee beverages have effects on glucose uptake, reduction of carbohydrate digestion and absorption, as well as modulation of gene expression and protein content of membrane transporters (SGLT1, GLUT2). (AU)