Das Gehirn als zentrale Schaltstelle des Stoffwechsels

Investigation of intraindividual differences in metabolism and diabetes risk has led to the identification of subgroups of prediabetes and diabetes mellitus. These groups show significant differences in their risk for complications and mortality. One feature of subgroups with high complication risk is a specific body fat distribution with increased visceral fat. This specific phenotype resembles that of individuals with insulin resistance in the brain, suggesting a potential pathophysiological role of brain insulin resistance in the development of such risk groups. Insulin action is not limited to peripheral tissues but is also present in the human brain. In the general population, a substantial number of individuals display brain insulin resistance. While insulin action in the brain typically influences eating behavior, coordinates metabolism in peripheral organs, and even impacts memory processes, these regulatory functions are impaired in case of brain insulin resistance. In the long-term, this appears to favor visceral fat accumulation. Insulin action in the brain differs between sexes, and the menstrual cycle also seems to influence brain insulin sensitivity and brain-derived regulation of metabolism. Preliminary smaller studies suggest that brain insulin resistance may be potentially treatable. Future studies are needed to clarify if improving brain insulin action could be a target to prevent or treat high-risk individuals and reduce their risk for complications.