Glutamine modulates the changes of intestinal intraepithelial γδT lymphocyte expression in mice with ischemia/reperfusion injury

Abstract

This study investigated the effect of glutamine (GLN) on small intestinal intraepithelial lymphocyte (IEL) γδT‐cell proinflammatory cytokines and apoptotic regulatory factor genes expression in a mouse model of ischemia/reperfusion (I/R) injury. Mice were assigned to a normal (NC) group and 3 I/R groups. Mice in the NC group had no ischemia treatment, whereas I/R groups had hindlimb ischemia 90 min with 0 h or 24 h reperfusion afterwards. IR0 group was sacrificed immediately after reperfusion. IR24S group was injected with saline and IR24G group was given 0.75 g GLN/kg body weight once via tail vein before reperfusion. IR24 groups were sacrificed 24 h after reperfusion. The small intestinal IEL γδT‐cells of the animals were isolated for further analysis. Results showed that IR injury resulted in lower small intestinal IEL γδT‐cells percentage and higher proinflammatory cytokines messenger (m)RNA expressions of interleukin (IL)‐1β, IL‐6, tumor necrosis factor‐α by IEL γδT‐cells. Compared to the IR24S group, the IR24G group had higher IEL γδT‐cells percentage. The fold changes of mRNA of anti‐apoptosis Bcl‐xl and proliferation gene IL‐7R expression in IR24G were higher in IEL γδT‐cells. Histological findings also showed that damage to the intestinal mucosa was less severe in the IR group with GLN.These results indicated that a single dose of GLN administered before reperfusion maintained small intestinal IEL γδT‐cell population and reduced the intestinal inflammatory cytokine expressions, which may consequently have ameliorated the severity of IR‐induced small intestinal epithelial injury.