Protective effect of the combination of glutamine and arginine on intestinal barrier function in rats receiving fluorouracil chemotherapy

Objective To investigate the protective effect of the combination of glutamine (Gln) and ar-ginine (Arg) on intestinal barrier function in rats receiving fluorouracil (5-FU) chemotherapy.Methods Totally 40 male SD rats receiving 5-FU chemotherapy were equally randomized into four groups:enteral nutrition group,Gln group (enteral nutrition+Gln),Arg group (enteral nutrition+Arg),and Arg+Gln group (enteral nutri-tion+Arg+Gln).Observe the changes post chemotherapy such as the changes of body weight and urine lactulose/mannitol ratio before and after chemotherapy were recorded.On the 8 th post-therapy day,the blood endotoxin level in portal vein was measured,and lymph nodes and blood in portal vein were taken for bacterial culture;colon and jejunum specimens were also taken to measure the height of jejunum villus and the thickness of colon and jejunum.Results Body weights of Gln group,Arg group,and Arg+Gln group significantly increased after chemotherapy (P 0.05).Lactulose/manni-tol ratio in each group significantly increased after chemotherapy (P 0.05).The blood endotoxin level in portal vein was signifi-cantly higher in enteral nutrition group than in other groups (P=0.000);the endotoxin level was significantly lower in Gln group than in Arg group (P=O.035) and Arg+Gln group (P=0.000);however,no such differ-ence was found between Arg group and Arg+Gln group (P=0.109).The height of jejunum villus and the thick-ness of jejunum were significantly lower in enteral nutrition group than those in the other groups (P=O.000);the thickness of colon was significantly lower in enteral nutrition group than those in Arg group and Arg+Gln group (P=0.000);however,no such difference was found when compared with Gln group (P=0.058).The thickness of colon (P=0.040) and jejunum (P=0.010) was significantly higher in Gln group than that in Arg group;but there was no significant difference in term of the height of jejunum villus (P=0.286).Compared with Arg+Gln group,the thickness of jejunum in Gln group was significantly higher,but there was no significant difference in terms of the height of jejunum villus (P=0.286) or the thickness of jejunum (P=0.190).The thickness of co-lon was significantly lower in Arg group than in Arg+Gln group (P=0.010),while no such significant difference was found in terms of the height of jejunum villus (P=0.803) or the thickness of colon (P=0.059) when com-pared with Arg+Gln group.The bacterial culture results were not significantly different among all groups.Conclu-sions The combination of Arg and Gln has protective effects on intestinal barrier in rats receiving 5-FU chemother-apy.The protective effect of Gln is superior to that of Arg.No synergistic effect exists between Arg and Gln. Key words: glutamine; arginine; intestinal permeability; gut barrier; fluorouracil