Die Rolle des Gehirns in der Regulation des Stoffwechsels

Zusammenfassung

Das Gehirn wird fortlaufend mit Informationen über die Verteilung und Menge der Energiereserven aus der Körperperipherie versorgt. Endokrine, autonome und kognitiv-hedonische Signale werden zentral integriert und rufen über anabole und katabole Signalwege Effekte auf den Gesamtorganismus hervor. Die Hormone Insulin und Leptin sind bedeutende Adipositassignale, d. h. ihre Konzentrationen im Blut spiegeln die Menge an Körperfett wieder und bilden einen negativen Feedbackmechanismus zwischen Körperperipherie und dem zentralen Nervensystem. Der hypothalamische Nucleus arcuatus ist die wichtigste zentralnervöse Struktur, die diese Informationen verarbeitet. Weiterhin ist das ZNS in der Lage, direkt die Konzentrationsänderungen bestimmter Nährstoffe zu messen und auf diese zu reagieren. Für die Entwicklung effektiver Therapien von Störungen der Energiebalance ist die weitere Aufklärung dieser neurobiologischen Vorgänge von entscheidender Bedeutung. Diese Arbeit gibt einen Überblick über die zentralnervöse Stoffwechselregulation und die ihr zugrunde liegenden molekularen Mechanismen.

Abstract

The brain is continuously supplied with information about the distribution and amount of energy stores from the body periphery. Endocrine, autonomic and cognitive-hedonic signals are centrally integrated and exert effects on the whole organism via anabolic and catabolic pathways. The adiposity signals insulin and leptin reflect the amount of body fat and are part of a negative feedback mechanism between the periphery and the central nervous system. The hypothalamic arcuate nucleus is the most important central nervous structure, which integrates this information. Furthermore, the CNS is able to directly measure and to respond to changes in the concentration of certain nutrients. In order to develop effective therapies for the treatment of disorders of energy balance the further elucidation of these neuro-biological processes is of crucial importance. This article provides an overview of the CNS regulation of metabolism and its underlying molecular mechanisms.

Schlüsselwörter

Leptin - Insulin - Hypothalamus - Nucleus arcuatus - Energiehomöostase

Keywords

leptin - insulin - hypothalamus - arcuate nucleus - energy homeostasis

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