OBJECTIVE - Incidence of type II diabetes mellitus is rapidly increasing worldwide. This study aimed to investigate whether blueberry, yoghurt, cyanidin-3-O-β-glucoside (C3G), or peptides with angiotensin converting enzyme (ACE) inhibitory activity, alone or in combination, alter body fat pad mass or weight and improve glucose tolerance in the C57BL/6 mouse induced obesity with a high-fat-high-carbohydrate (HFHC) diet.
RESEARCH DESIGN AND METHODS – 6-weeks-old male C57BL/6 mice consumed a HFHC diet for eight week to induced obesity. Obese mice were fed different dietary supplements, including blueberry, C3G, yoghurt, peptides extracted from yoghurt, alone and in combination of blueberry and yogurt, or C3G and peptides for additional eight weeks. Mice were killed via cardiac puncture following deep anaesthesia using isoflurane. Sequentially, heart, epididymal fat, mesenteric fat, liver and kidney were collected and weighed. Body weight was measured twice a week. Echo MRI system was utilised to determine the body composition every four weeks. Intraperitoneal glucose tolerance test was completed before the dietary supplementation (baseline) and at the end of experiment.
RESULTS – Body weight and body fat were significantly decreased and glucose tolerance was improved in yoghurt, peptides and the combination of C3G and peptides at the end of the dietary supplementation, compared to the HFHC group. However, body fat was significantly increased in blueberry group, compared to HFHC group. The ratio of epididymal fat to body weight was significantly decreased in yoghurt group, compared to HFHC group. The ratio of mesenteric fat, liver and kidney to body weight in all treatment groups did not differ from the HFHC group.
CONCLUSIONS - Yoghurt and its peptides with ACE inhibitory activity decrease body weight and body fat and improve glucose uptake in obese mice. This provides a potential novel approach for the regulation of glucose metabolism in obese and diabetic individuals.