A new study was designed to find whether prolonged receptor antagonism using daily injections of GIP was capable of reversing diet-induced obesity and related metabolic abnormalities in an animal model.
The 8-week old mice selected for the study were given access to drinking water and a high fat diet—20% protein and 35% protein, percent of total energy 26.15kg/g. Control mice were fed a standard rodent maintenance diet—10% fat, 30% protein, 60% carbohydrate, percent of total energy of 12.99.
Before the study, mice were fed a high-fat diet for 160 days. Another set of mice were given a high-fat diet for 112 days before measuring circulating GIP and GLP-1 levels. For both samples, obesity and diabetes were unmistakably evident.
Among the key findings were that consumption of the high-fat diet produced progressive weight gain and elevations of plasma and gyrated hemoglobin, resulting in impaired insulin sensitivity and glucose intolerance within 10 days. (Pro3)GIP countered many of the detrimental effects of high fat diet on body weight and indices of glucose and lipid metabolism.
This study showed that blocking GIP activity using (Pro3)GIP in mice with established, high fat diet-induced obesity and diabetes results in significant weight loss, improvement of insulin resistance and amelioration of diabetes. These findings represent an interesting new approach to the treatment of obesity and metabolic disturbances.
Nigel Irwin, PH.D., of the research team said that possible parallels exist with the benefits of gastric bypass surgery in treating gross obesity and diabetes in people. In this procedure nutrients surgically bypass the area of the small intestine, resulting in a deficiency of circulating GIP.
Source: American Physiological Society (APS)