Peripheral tissue-brain interactions in the regulation of food intake

Gastrointestinal peptides controlling body weight homeostasis

Obesity has become an international public health problem. Unfortunately, effective treatment options are limited. In the last 20 years, research in obesity and associated pathologies has derived in a significant increase in the knowledge of the physiological and molecular mechanism regulating body mass, such as gastrointestinal-neuroendocrine communications. Gut-brain peptides may provide attractive therapeutic targets against this disease. This review summarizes research into energy balance through gastrointestinal tract peptides. Understanding these molecular mechanisms will provide new pharmacological targets for the treatment of obesity and appetite disorders.

Nicotine treatment regulates neuropeptide S system expression in the rat brain

Nicotine has marked effects on sleep, arousal and body weight. However, the neuronal mechanisms underlying these actions are not fully understood. Neuropeptide S (NPS) is a recently discovered neuropeptide regulating sleep, anxiety and feeding. Here, we examined the effect of acute and chronic nicotine treatment on the expression of NPS and its receptor (NPS-R) in the hypothalamus and brainstem of rats by using real-time PCR. Our results showed that chronic nicotine treatment induced significant changes in NPS and NPS-R expression whereas acute treatment exclusively induces a marked increase in the mRNA levels of NPS-R in the brainstem. Interestingly, we detected no changes in the expression levels of other set of genes present both in hypothalamus and brainstem. Overall, these data suggest that NPS system is specifically regulated by nicotine in the rat hypothalamus and brainstem.