Effect of glutamine on heat shock protein-70 and tumor necrosis factor-α expession in endotoxemic rats

AIM: To study the protective effect of glutamine (Gln) against endotoxemia by observing the effect of glutamine on heat shock proteins (HSPs) and tumor necrosis factor-α (TNF-α) in endotoxemic rats. METHODS: The rats were randomly divided into 3 groups, lipopolysaccharide group (LPS), glutamine-treated group (Gln) and control group (C). The blood was drawn from lateral tail vein for analysis of cytokine levels at 0, 2, 4 and 6 h post-lipopolysaccharide (LPS) challenge. TNF-α was measured by radioimmunity assay. Multiple tissues were harvested from the rats, and HSP70 was detected by immunohistochemistry. At the same time, lung, liver, and ileum tissue section were stained with hematoxylin and eosin. RESULTS: Gln treatment resulted in marked attenuation of TNF-α expression at 2 h post-LPS injection (P＜0.01). Gray gradients of HSP70 in lungs, liver and ileum tissue in group Gln were much lower than those of group LPS (P＜0.05), This suggested that HSP70 content in these tissues of group Gln was higher than that of group LPS. Tissue sample from lung, liver and ileum revealed significantly less evidence of endotoxin-induced tissue damage in Gln-treated animals. CONCLUSION: Gln can significantly enhance HSP70 expression in multiple tissues of endotoxin-treated rats. A single dose of intravenous Gln given concomitantly with an endotoxin injury can markedly reduce organ histological damage, and attenuate pro-inflammatory cytokine release.