The Study Of SH2-Bβ Expression And Functions In Hypothalamus And Lung Of Obese Mice

OBJECTIVES:The aim of this study was to compare the difference of SH2-B(3expression in hypothalamus and lung and leptin level in serum between diet-induced obese mice and normal mice,and to explore the association of SH2-Bβand obesity and inflammation.Inorder to find the mechnism and good treatment for obesity-asthma.METHODS:45 C57BL/6 mice(male) aged 6 weeks were used thoughout the study. Mice were randomized to a standard rodent chow (NC,n=20) or to a high fat diet chow (HFD,n=25).After 12 weeks on diet, bodylength(from top of nose to anus) and body weight were measured.and according to (Wt>NC Wt mean+2S),20 HFD mice were chosen from 25 HFD to be obese group.In the morning without diet,10 from each group were used to measure the airway resistance through animal respiratory machine,other 10 were taken blood from eyes, taken hypothalamus for western blot detecting SH2-Bβexpression and taken lung for immunohistory detecting SH2-Bβexpression.Blood serum was separated by centifugation and samples were stored at -70℃until further use.Fasting plasma glucose (FPG) was determind using glucose oxidase;The fasting plasma insulin (FINS)and leptin(LEP)were tested by ELISA; HOMA-IR (FPG* FINS/22.5)and Lee's index[(wt(g)1/3*1000/length(cm)] was calculated.RESULTS:1.Compared with the NC group, Wt, Lee's index, FPG,LEP,FINS and HOMA-IR were increased in obesemice.2. Immunohistochemistry and HE stained demonstrated that more imflammatory cells were in the lung in obese mice than NC group, and the mean optic density(MOD) 0.685±0.025 of SH2-Bβpositive substance in the airway epithelium and imflammatory cells in obese mice was much higher than NC group(0.127±0.019) (P＜0.01).3.Western Blot demonstrated that the mean ratio of SH2-BβMOD toβ-actin MOD in hypothalamus was (0.686±0.056) in obese mice, much lower than (2.487±0.204) (P＜0.01) in normal control group (P＜0.01)4.analysis of correlation showed the level of serum LEP was negtively corelated with SH2-Bβexpression in hypothalamus and positively corelated with SH2-Bβexpressionin lung.CONCLUSION:1.High fat diet may induce leptin and insulin resistance,and decreased SH2-Bβexpression in hypothalamus and induced obesity.2. The lungs of high fat diet mice were in the inflammatory condition,SH2-Bpexpression in airway epithelium and imflammatory cells was increased and make the airway resistance higher.