Role of brain tryptophan and serotonin in secondary anorexia

Abstract

Anorexia and reduced energy intake contribute to worsen the prognosis of patients suffering from a number of chronic diseases, by promoting skeletal muscle wasting, leading to the development of malnutrition and eventually cachexia. The pathogenesis of cancer anorexia is still matter of debate. Many possible mediators, including hormones, peptides, and neurotransmitters, appear to be involved. However, consistent animal and clinical data suggest that brain tryptophan and serotonin may represent a common final pathway shared by many contributing factors. Supporting this hypothesis, recent data showed that the manipulation of brain tryptophan availability ameliorates anorexia and food intake in cancer patients.