Effects of visfatin on the apoptosis of intestinal mucosal cells in immunological stressed rats.

This study was undertaken to determine if visfatin is involved in the inflammation or apoptosis introduced by LPS in rats. Forty 8-week old Wistar rats were divided into four groups (n=10 in each group) and injected with saline, visfatin, LPS and visfatin+LPS co-stimulated via caudal vein. The duodenum, jejunum and ileum were harvested from all the rats. Compared to the saline treated group, visfatin significantly increased the number of TUNEL-positive apoptotic cells and the expression of caspase-3 protein in intestinal mucosa. Similarly, ELISA and western blot analysis also showed the up-regulation of pro-caspase-3 and cleaved caspase-3 expression in the visfatin group compared to the control group. In contrast to LPS, visfatin down-regulated the expression of cleaved-caspase-3 in the visfatin+LPS co-stimulated group, resulting in a significant decrease in apoptosis in intestinal mucosal cells. We observed more pro-caspase-3 positive cells in the visfatin+LPS co-stimulated group. The results indicate that, in the presence of LPS, visfatin plays an important role in the regulation of cell apoptosis and inflammation.

The regulation mechanism of apoptosis by visfatin in the mesenteric lymph nodes of LPS-treated rats.

Visfatin is an adipocytokine displaying multiple functional properties, which plays a role in the regulation of cell apoptosis and inflammation by an as yet unidentified mechanism. The aim of the present study was to determine if visfatin is involved in apoptosis pathway induced by LPS in rat Mesenteric lymph nodes (MLNs). Experimental rats were divided into four groups and MLNs samples were collected from each group. The morphological changes of the MLNs were examined by histological imaging. CD68 and ENPP1 were detected with immunohistochemistry and Western Blot. Apoptosis was evaluated with TUNEL and Flow Cytometry, the mRNA levels of the apoptosis-related genes were detected by qRT-PCR, and the protein levels of the apoptotic-related factors were detected by western blot. The main results showed that visfatin could significantly increase the macrophages in MLNs and prevent cell apoptosis from LPS-induced mesenteric lymph nodes, activate apoptotic signaling pathways and regulate the mRNA levels of the apoptosis-related genes. Visfatin had a pro-apoptotic effect on normal MLNs, whereas it exerted an anti-apoptotic effect during LPS-induced cell apoptosis in rat MLNs. In short, visfatin plays a dual role in the apoptosis in rat MLNs, which is mediated by both the mitochondrial apoptotic pathway and the death-receptor apoptotic pathway.

The role of visfatin on the regulation of inflammation and apoptosis in the spleen of LPS-treated rats.

The purpose of the present study is to determine if visfatin is involved in inflammation or apoptosis induced by LPS in rat. Forty Wistar rats were divided into four groups: saline group, LPS group, visfatin group and Visfatin + LPS co-stimulated group. Spleen samples from each group of rats were collected for study. The spleen structure was examined by histological imaging. Apoptosis was evaluated with TUNEL reaction. Caspase-3 was detected with immunohistochemistry and western blot. The apoptosis-related genes were detected by qPCR and inflammatory cytokines were tested by ELISA. Our main findings were as follows. (1) Macrophages were markedly increased in the visfatin group compared with the saline group. This finding was confirmed when spleen samples were examined with western blot using CD68 antibody. (2) Visfatin promoted the expression of CD68 and caspase-3 in rat spleen, whereas visfatin could inhibit the expression of CD68 and activated caspase-3 in spleen of LPS-induced acute inflammation. (3) Visfatin had a pro-apoptotic effect on normal rat spleen, whereas it exerted an anti-apoptotic effect during LPS-induced lymphocytes apoptosis in rat spleen. Moreover, the effect of visfatin on cell apoptosis was mediated by the mitochondrial pathway. (4) Visfatin could modulate both the anti-inflammatory cytokines and pro-inflammatory cytokines in rat spleen, such as IL-10, IL-4, IL-6, TNF-α and IL-1ß. Taken together, we demonstrate that visfatin could participate in the inflammatory process in rat spleen by modulating the macrophages and inflammatory cytokines. Also, visfatin plays a dual role in the apoptosis in rat spleen, which is mediated by the mitochondrial pathway.