For the first time DZD scientists evaluated the specific brain areas affected by insulin resistance. They compared the cerebral blood flow (CBF) of lean and overweight/obese participants after application of intranasal insulin. Dr. Stephanie Kullmann, Dr. Hubert Preißl and colleagues (Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at the Eberhard-Karls-University of Tübingen) found a significant CBF decrease in the hypothalamus in both lean and overweight/obese participants compared with placebo. The magnitude of this response correlated with visceral adipose tissue independent of other fat compartments. Furthermore, they observed a differential response in the lean compared with the overweight/obese group in the prefrontal cortex, resulting in an insulin-induced CBF reduction in lean participants only. This prefrontal cortex response significantly correlated with peripheral insulin sensitivity and eating behavior measures as disinhibition and food craving. Behaviorally, a significant reduction for the wanting of sweet foods after insulin application was observed in lean men only.
The identification of hormone-brain interactions that modulate food intake can potentially aid in the development of effective obesity therapies. Reduction of body weight would also contribute to the prevention of type 2 diabetes.
Kullmann S, Heni M, Veit R, Scheffler K, Machann J, Häring HU, Fritsche A, Preissl H. Selective Insulin Resistance in Homeostatic and Cognitive Control Brain Areas in Overweight and Obese Adults. doi: 10.2337/dc14-2319, Diabetes Care March 20, 2015
Link to the publication:http://care.diabetesjournals.org/content/early/2015/03/19/dc14-2319.long