Intestinal ischemia-reperfusion induces the release of IL-17A to regulate cell inflammation, apoptosis and barrier damage.

Intestinal ischemia-reperfusion (I/R) injury promotes the release of IL-17A, and previous studies have indicated that TGF-ß activated kinase 1 (TAK1) is an important signaling molecule in the regulatory function of IL-17A. The present study aimed to explore the potential effects of IL-17A release in intestinal I/R injury, and to investigate the underlying regulatory mechanisms. Initially, the expression levels of TAK1 and JNK in a hypoxia/reoxygenation model were determined, and the effects of TAK1-knockdown on JNK phosphorylation and the viability, inflammation, apoptosis and barrier function of Caco-2 cells were assessed using Cell Counting Kit-8, reverse transcription-quantitative PCR, TUNEL and transepithelial electrical resistance assays, respectively. Subsequently, an antibody targeting IL-17A was used, and the effects of the IL-17A antibody on the expression levels of TAK1 as well as cell viability, inflammation, apoptosis and barrier function were determined. The results of the present study demonstrated that TAK1-knockdown markedly reduced JNK phosphorylation and improved the levels of cell viability, inflammation, apoptosis and barrier function via the MAPK signaling pathway. In addition, treatment with the IL-17A antibody inhibited the expression of TAK1, and reversed the aforementioned effects of TAK1 on Caco-2 cells. In conclusion, intestinal I/R induces the release of IL-17A to regulate cell viability, inflammation, apoptosis and barrier damage via the TAK1/MAPK signaling pathway.

Can pigment gallstones be induced by biliary stricture and prevented by medicine in Guinea pigs?

AIM: To determine the relationship between biliary stricture and pigment gallstone formation, and the prevention of pigment gallstones with medicine. METHODS: One hundred and eighteen male guinea pigs were randomly divided into four groups: stricture group (S, n = 30) underwent partial ligation of common bile duct, and fed on regular chow; S plus medicine group (S+M, n = 27) underwent the same operation but fed on medicinal chow (0.3 g chenodeoxycholic acid, 0.5 g glucurolactone, and 0.5 g aspirin were mixed up in 1.2 kg regular chow); medicinal control group (C+M, n = 30) was free of operation, and fed on medicinal chow; and control group (C, n = 31) was free of operation and fed on regular chow. One week later, laparotomy was performed, and the bile of gallbladder was collected, measured, and cultured. RESULTS: Gallstones were identified. Pigment gallstones were induced by biliary stricture in 95% (22/23) of S group. In the S+M group, the incidence of gallstone was reduced to 55% (11/20, vs S group, P < 0.01). The changes of indirect bilirubin and ionized calcium in the bile were consistent with gallstone incidences. CONCLUSION: Biliary stricture can cause pigment gallstone formation in guinea pigs, and the medicines used can lower the incidence of gallstones. The bilirubin and ionized calcium play important roles in pigment gallstone formation.