%0 Journal Article
%T Interleukin-7, a New Cytokine Targeting the Mouse Hypothalamic Arcuate Nucleus: Role in Body Weight and Food Intake Regulation
%A Laurence Macia
%A Odile Viltart
%A Myriam Delacre
%A Christelle Sachot
%A Laurent H¨¦liot
%A James P. Di Santo
%A Isabelle Wolowczuk
%J PLOS ONE
%D 2012
%I Public Library of Science (PLoS)
%R 10.1371/journal.pone.0009953
%X Body weight is controlled through peripheral (white adipose tissue) and central (mainly hypothalamus) mechanisms. We have recently obtained evidence that overexpression of interleukin (IL)-7, a critical cytokine involved in lymphopoiesis, can protect against the development of diet-induced obesity in mice. Here we assessed whether IL-7 mediated its effects by modulating hypothalamic function. Acute subcutaneous injection of IL-7 prevented monosodium glutamate-induced obesity, this being correlated with partial protection against cell death in the hypothalamic arcuate nucleus (ARC). Moreover, we showed that IL-7 activated hypothalamic areas involved in regulation of feeding behavior, as indicated by induction of the activation marker c-Fos in neural cells located in the ventromedial part of the ARC and by inhibition of food intake after fasting. Both chains of the IL-7 receptor (IL-7R¦Á and ¦Ãc) were expressed in the ARC and IL-7 injection induced STAT-3 phosphorylation in this area. Finally, we established that IL-7 modulated the expression of neuropeptides that tune food intake, with a stimulatory effect on the expression of pro-opiomelanocortin and an inhibitory effect on agouti-related peptide expression in accordance with IL-7 promoting anorectic effects. These results suggest that the immunomodulatory cytokine IL-7 plays an important and unappreciated role in hypothalamic body weight regulation.
%U http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0009953