The Physiology of Weight Loss after Gastric Bypass

Our current research program is based on a prospective study of of a cohort of morbidly obese individuals who will undergo weight reduction therapy through the MGH weight center, of which I am director. DNA will be banked, and all subjects will be characterized by metabolic, hormonal, cardiorespiratory, psychological and anthropomorphic measurements before and after initiation of a closely supervised outpatient program of caloric restriction coupled with behavioral modification. A subset of this group will subsequently undergo gastric bypass surgery, with continued characterization of these parameters, as well as with fasting and stimulated hormone levels (insulin, leptin, ghrelin, NPY, etc,) .

In laboratory-based studies, we have developed a rat model of gastric bypass, and are seeking to extend this to the mouse, so as to utilize the numerous genetically modified murine models of obesity.

References:

1. Kaplan LM.      Body weight regulation and obesity. J Gastrointest Surg. 2003;7:443-51.

2. Hoppin AG, Kaplan LM. The leptin era: new insight into the mechanisms of body weight homeostasis. J Pediatr Gastroenterol Nutr. 1999;29:250-64.