Deoxynivalenol-induced anorexia is mediated by brain-gut peptides through CaSR-TRPM5 signaling axis.

Deoxynivalenol (DON), a secondary metabolite produced by Fusarium, can widely contaminate foods and feeds, endangering human and animal health. DON can cause anorexia in animals. However, the specific mechanism is unclear. In this study, in vivo and in vitro experiments were conducted in mice and mouse intestinal organoid, respectively. Specific antagonists NPS2143, U73122, Xestospongin C, TPPO, EGTA, and Nitrendipine were selected to inhibit CaSR, PLCβ2, IP3R, TRPM5, extracellular calcium, and L-type VSCCs to explore the effect of the CaSR-TRPM5 signaling axis in DON-induced anorexia and secretion of brain-gut peptide. The results showed that these antagonists attenuated the DON-induced anorexia and secretion of the brain-gut peptides CCK, PYY, GLP-1, and GIP. DON could significantly increase the expression of hypothalamic anorectic genes MC4R, POMC, and CART. Blocking the CaSR-TRPM5 signaling axis could attenuate these changes. The mouse small intestinal organoid can be induced to differentiate into EECs by blocking the Wnt/Notch/Mek pathway. DON-induced brain-gut peptides secretion was attenuated by inhibition of CaSR-TRPM5 signaling axis in mouse intestinal organoid. In summary, DON could act on enteroendocrine cells to induce secretion of brain-gut peptide and activate the hypothalamic anorectic genes to evoke anorexia through the CaSR-TRPM5 signaling axis.