Glutamine supplementation alleviated aortic atherosclerosis in mice model and in vitro.

This study aimed to clarify the role of glutamine in atherosclerosis and its participating mechanism. Forty C57BL/6J mice were divided into wild control (wild Con), ApoE- /- control (ApoE- /- Con), glutamine + ApoE- /- control (Glut + ApoE- /- Con), ApoE- /- high fat diet (ApoE- /- HFD), and glutamine + ApoE- /- HFD (Glut + ApoE- /- HFD) groups. The degree of atherosclerosis, western blotting, and multiomics were detected at 18 weeks. An in vitro study was also performed. Glutamine treatment significantly decreased the degree of aortic atherosclerosis (p = 0.03). O-GlcNAcylation (O-GlcNAc), IL-1ß, IL-1α, and pyruvate kinase M2 (PKM2) in the ApoE- /- HFD group were significantly higher than those in the ApoE- /- Con group (p < 0.05). These differences were attenuated by glutamine treatment (p < 0.05), and aggravated by O-GlcNA transferase (OGT) overexpression in the in vitro study (p < 0.05). Multiomics showed that the ApoE- /- HFD group had higher levels of oxidative stress regulatory molecules (guanine deaminase [GUAD], xanthine dehydrogenase [XDH]), proinflammatory regulatory molecules (myristic acid and myristoleic acid), and stress granules regulatory molecules (caprin-1 and deoxyribose-phosphate aldolase [DERA]) (p < 0.05). These differences were attenuated by glutamine treatment (p < 0.05). We conclude that glutamine supplementation might alleviate atherosclerosis through downregulation of O-GlcNAc, glycolysis, oxidative stress, and proinflammatory pathway.

Application of perioperative immunonutrition for gastrointestinal surgery: a meta-analysis of randomized controlled trials.

The aim of this study was to evaluate clinical and economic validity of perioperative immunonutrition and effect on postoperative immunity in patients with gastrointestinal cancers. Immunonutrition diet supplemented two or more of nutrients including glutamine, arginine, omega-3 polyunsaturated fatty acids and ribonucleic acids. A meta-analysis of all relevant clinical randomized controlled trials (RCTs) was performed. The trials compared perioperative immunonutrition diet with standard diet. We extracted RCTs from electronic databases: Cochrane Library, MEDLINE, EMBASE, SCI and assessed methodological quality of them according handbook for Cochrane reviewer in June 2006. Statistical analysis was performed by RevMan4.2 software. Thirteen RCTs involving 1269 patients were included. The combined results showed that immunonutrition had no significant effect on postoperative mortality (OR =0.91, p= 0.84). But it had positive effect on postoperative infection rate (OR =0.41, p<0.00001), length of hospital stay (WMD=-3.48, p<0.00001). Furthermore, it improved immune function by increasing total lymphocytes (WMD=0.40, p<0.00001), CD4 levels (WMD=11.39, p<0.00001), IgG levels (WMD=1.07, p=0.0005) and decreasing IL6 levels (WMD=-201.83, p<0.00001). At the same time, we did not found significant difference in CD8, IL2 and CRP levels . There were no serious side effects and two trials found low hospital cost. In conclusion, perioperative diet adding immunonutrition is effective and safe to decrease postoperative infection and reduce length of hospital stay through improving immunity of postoperative patients as compared with the control group. Further prospective study is required in children or critical patients with gastrointestinal surgery.