Effects of Schistosoma japonicum infection on the expression of Arg-1 and Fizz-1 proteins in liver tis-sues of mice with high-fat diet induced obesity / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the effects of Schistosoma japonicum infection on selective activation of macrophages and insulin resistance in liver tissues of mice with high-fat diet induced obesity and the possible mechanism. Methods Thirty-six male C57BL/ 6J mice were randomly divided into 3 groups in-cluding normal control group(NC group,n=12),high-fat diet feeding group(HF group,n=12)and high-fat diet feeding with Schistosoma japonicum infection group(HSj group,n=12). Specimens were collected 6 and 12 weeks after high-fat diet feeding. The levels of fasting blood glucose(FBG),fasting plasma insulin (FINS)and homeostasis model assessment for insulin resistance index(HOMA-IR)were detected. The ex-pression of interleukin-6(IL-6),arginase-1(Arg-1)and found in inflammatory zone-1(Fizz-1)at mRNA and protein levels were detected by semi-quantitative reverse transcription polymerase chain reaction(RT-PCR)and immunohistochemistry,respectively. Results The mice from HF group showed higher levels of HOMA-IR than those form NC group and HSj group by the end of 6 and 12 weeks after infection(P﹤0. 05). The levels of HOMA-IR in mice from HF group were increased by the end of week 12 after infection as com-pared with those at week 6(P>0. 05). The levels of IL-6 in mice from both HF group and HSj group were higher than those from NC group by the end of week 6 after infection(P﹤0. 05). Higher levels of IL-6 were detected in mice from HF group as compared with those from HSj group and NC group by the end of week 12 after infection(P﹤0. 05). The expression of Arg-1 and Fizz-1 in mice form HF group were lower than those from NC group by the end of 6 and 12 weeks after infection(P﹤0. 05). Arg-1 was highly expressed in mice form HSj group,followed by those from NC and HF groups 12 weeks after infection. The expression of Fizz-1 in mice from HSj group was the highest among the three groups by the end of week 6 and 12 after infection (P﹤0. 05). Conclusion The proinflammatory effects on mice with diet induced obesity were induced dur-ing acute infection of Schistosoma japonicum cercariae(6 weeks). The chronic infection of Schistosoma ja-ponicum cercariae(12 weeks)might be helpful in reversing hepatic insulin resistance in mice with diet in-duced obesity by changing the polarity of macrophages in liver tissues.