Nesfatin-1 Regulates Feeding， Glucosensing and Lipid Metabolism in Rainbow Trout.

Nesfatin-1 is an 82 amino acid peptide that has been involved in a wide variety of physiological functions in both mammals and fish. This study aimed to elucidate the role of nesfatin-1 on rainbow trout food intake， and its putative effects on glucose and fatty acid sensing systems. Intracerebroventricular administration of 25 ng/g nesfatin-1 resulted in a significant inhibition of appetite， likely mediated by the activation of central POMC and CART. Nesfatin-1 stimulated the glucosensing machinery (changes in ， and mRNA expression) in the hindbrain and hypothalamus. Central fatty acid sensing mechanisms were unaltered by nesfatin-1， but this peptide altered the expression of mRNAs encoding factors regulating lipid metabolism (α， and γ)， suggesting that nesfatin-1 promotes lipid accumulation in neurons. In the liver， intracerebroventricular nesfatin-1 treatment resulted in decreased capacity for glucose use and lipogenesis， and increased the potential of fatty acid oxidation. Altogether， the present results demonstrate that nesfatin-1 is involved in the homeostatic regulation of food intake and metabolism in fish.