RESUMO
Dietary selenium intake within the normal physiological range is critical for various supporting biological functions. However, the effect of nano-selenium on biological mechanism of goblet cells associated with autophagy is largely unknown.The purpose of this study was to investigate the effect of nano-selenium on the mucosal immune-defense mechanism of goblet cells (GCs) in the small intestine of laying hens.The autophagy was determined by using specific markers. Nano-selenium-treated group of immunohistochemistry (IHC), immunofluorescence (IF), and western blotting (WB) results indicated the strong positive immune signaling of microtubule-associated light chain (LC3) within the mucosal surface of the small intestine. However, weak expression of LC3 was observed in the 3-methyladenine autophagy inhibitor (3-MA) group. IHC and IF staining results showed the opposite tendency for LC3 of sequestosome 1 (P62/SQSTM1). P62/SQSTM1 showed strong positive immune signaling within the mucosal surface of the small intestine of the 3-MAgroup, and weak immune signaling of P62/SQSTM1 in the nano-selenium-treated group. Moreover, pinpointing autophagy was involved in the mucosal production and enrichment of mucosal immunity of the GCs. The morphology and ultrastructure evidence showed that the mucus secretion of GCs was significantly increased after nano-selenium treatment confirmed by light and transmission electron microscopy. Besides that, immunostaining of IHC, IF and WB showed that autophagy enhanced the secretion of Mucin2 (Muc2) protein in nano-selenium-treated group. This work illustrates that the nano-selenium particle might enhance the mucosal immune-defense mechanism via the protective role of GCs for intestinal homeostasis through autophagy.
