Central nesfatin-1-expressing neurons are sensitive to peripheral inflammatory stimulus.
Recently, a novel factor with anorexigenic properties was identified and called nesfatin-1. This protein (82 aac) is not only expressed in peripheral organs but it is also found in neurons located in specific structures including the hypothalamus and the brainstem, two sites strongly involved in food intake regulation. Here, we studied whether some of the neurons that become activated following an injection of an anorectic dose of lipopolysaccharides (LPS) exhibit a nesfatin-1 phenotype. To this end, we used double immunohistochemistry to target the expression of the immediate-early gene c-fos and of nesfatin-1 on coronal frozen sections of the rat brain. The number of c-Fos+/nesfatin-1+ neurons was evaluated in the immunosensitive structures reported to contain nesfatin-1 neurons; i.e. paraventricular hypothalamic nucleus (PVN), supraoptic nucleus (SON), arcuate nucleus (ARC) and nucleus of the solitary tract (NTS). LPS strongly increased the number of c-Fos+/nesfatin-1+ neurons in the PVN, SON and NTS, and to a lesser extent in the ARC. Triple labeling showed that a portion of the nesfatin-1 neurons activated in response to LPS within the NTS are catecholaminergic since they co-express tyrosine hydroxylase (TH). Our data therefore indicate that a portion of nesfatin-1 neurons of both the hypothalamus and brainstem are sensitive to peripheral inflammatory signals, and provide the first clues suggesting that centrally released nesfatin-1 may contribute to the neural mechanisms leading to endotoxaemic anorexia.
Centre de Recherche en Neurobiologie-Neurophysiologie de Marseille, UMR 6231 CNRS, Marseille, France. marion.bonnet13@hotmail.fr
Marion S
MS
Bonnet
Emilie
E
Pecchi
Jérôme
J
Trouslard
André
A
Jean
Michel
M
Dallaporta
Jean-Denis
JD
Troadec
D000818:Animals; D000855:Anorexia / Q000139:chemically induced; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism; D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D007249:Inflammation / Q000503:physiopathology*; D008070:Lipopolysaccharides / Q000276:immunology / Q000494:pharmacology; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D000080866:Nucleobindins; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D008070:Lipopolysaccharides; D009419:Nerve Tissue Proteins; C000630652:Nucb1 protein, rat; D000080866:Nucleobindins; D016760:Proto-Oncogene Proteins c-fos