AIM:To investigate the effects of glucagon-like peptide-1 (GLP-1) receptor agonist exendin-4 on white adipose tissue (WAT) and the underlying mechanisms.METHODS:Male C57BL/6J mice (8 weeks) were chal-lenged by high-fat diet for 12 weeks, and were randomly divided into saline group and exendin-4 group.The mRNA expres-sion of sirtuin 1 (SIRT1), adipose triglyceride lipase (ATGL), TNF-αand adiponectin of WAT was detected by real-time PCR.3T3-L1 adipocytes or mouse embryonic fibroblasts cells were treated with exendin-4 for 24 h.The protein levels of SIRT1, ATGL and hormone-sensitive lipase (HSL) were determined by Western blot.RESULTS:Exendin-4 significantly decreased epididymal fat weight, fasting blood glucose and serum triglyceride levels ( P<0.05) , and reduced body weight and serum TNF-αlevel.The mRNA expression of SIRT1, ATGL and adiponectin in WAT was all significantly up-regulated by exendin-4, which were contrary to the down-regulation of TNF-αmRNA expression (P<0.05).Exendin-4 promoted the protein expression of SIRT1, ATGL, and HSL in 3T3-L1 adipocytes in a dose-dependent manner.Less lipid droplets with up-regulation of lipolytic protein expression were observed when combined with SIRT1 agonist treatment, which were suppressed by SIRT1 inhibitor.Deletion of SIRT1 led to larger adipocytes with more lipid droplets, and the effect of ex-endin-4 on the lipolysis disappeared when SIRT1 was deficient.CONCLUSION:Exendin-4 promotes lipolysis in WAT of obese mice via activation of SIRT1.

Objective To observe the influence of direct peritoneal resuscitation on liver function in hemorrhagic shock rabbits with pyruvate peritoneal dialysis solution instead of lactate peritoneal dialysis solution. Methods 48 hemorrhagic shock rabbits were randomly divided into conventional intravenous resuscitation group (group A),intravenous resuscitation plus intraperitoneal injection of lactate peritoneal dialysis solution group (group B),intravenous resuscitation plus intraperitoneal injection of pyruvate peritoneal dialysis group(group C), intravenous pyruvate peritoneal dialysis resuscitation plus intraperitoneal injection of pyruvate peritoneal dialysis group(group D). The hemodynamic changes were observed and the AST and ALT were measured respectively before and 60 min after shock ,60 min and 180 min after resuscitation. The dry/wet weight ratio ,MDA and SOD of liver tissue were measured,and the liver morphological changes were observed. Results After the completion of shock resuscitation,MAP of all groups were almost restored to the basal level. 180 min after resuscitation,the MAP of animals in group A was lowered than that in group B,C and D(P<0.05). After shock,ALT and AST were signifi-cantly higher than those before shock ,but no significant difference was found between groups (P > 0.05). After resuscitation,ALT and AST continued to decline in all groups,but the decline range increased with the order of A, B,C,D group(P < 0.05). The water content and MDA in liver tissue decreased with the order of A,B,C,D group,while the SOD increased and the differences between groups were significant(P<0.05). And the degree of liver tissue morphological injury also relieved correspondingly. Conclusion Pyruvate substituting lactate peritoneal dialysis solution peritoneal resuscitation can be more effective in reducing liver damage of hemorrhagic shock rabbits.

Objective To investigate the effect of EP4 gene silencing on the growth and migration of K1 cells. Methods K1 cells with stable knockdown of EP4 were constructed with lentiviral vector. QRT-PCR and western blot analysis were used to detect the expression of EP4 mRNA and protein in K1 cells. CCK8 assay and flow cytometry were employed to measure cell viability and apoptosis. Transwell assay was applied to detect cell migration. Results Compared with the negative control group,the mRNA and protein expression of EP4 were sig-nificantly decreased in K1 cells with stable knockdown of EP4. Furthermore,shRNA-mediated silencing of EP4 gene remarkably suppressed cell viability and induced apoptosis of K1 cells.The migration of K1 cells with knock-down of EP4 was decreased compared with the negative control group. Conclusions EP4 gene silencing can in-hibit growth and induce apoptosis of K1 cells.Downregulation of EP4 can significantly reduce migration of K1 cells.

OBJECTIVE： To optimize the extraction technology of Shengmaiyin polysaccharide， and to investigate the regulation effects of Shengmaiyin and its polysaccharide on intestinal function of spleen deficiency model rats. METHODS： The contents of polysaccharide were determined by phenol-sulfuric acid method， and the extraction rate of polysaccharide was calculated. Using extraction rate of Shengmaiyin polysaccharide as investigation index， singel factor and orthogonal tests were used to optimize material-liquid ratio， extraction time， extraction temperature and extraction times of Shengmaiyin polysaccharide. Validation test was also conducted. Totally 80 male SD rats were randomly divided into blank group， model group， Shengmaiyin low-dose， medium-dose and high-dose groups （350， 700， 1 400 g/L， by crude drug）， Shengmaiyin polysaccharide low-dose， medium-dose and high-dose groups （24.5， 49， 98 g/L， by crude drug）， with 10 rats in each group. Except for blank group， other groups were given Rheum palmatum water decoction 10 mL/kg to induce spleen deficiency model， once a day， for consecutive 15 d. Since the 16th day， blank group and model group were given isovolumic water intragastrically， while other groups were given corresponding drugs， once a day， for consecutive 10 d. The general status of rats and body weights were recorded in each group. The serum contents of D-xylose， gastrin （GAS） and vasoactive intestinal peptide （VIP） were detected by phloroglucinol method or ELISA. RESULTS： The optimal extraction technology of Shengmaiyin polysaccharide was material-liquid ratio 1 ∶ 10（g/mL）， extraction time 45 min， extraction temperature 80 ℃， extracting for 1 time. Results of validation test showed that extraction rates of the polysaccharide in 3 times were 7.43％， 7.64％， 7.80％ （RSD＝1.01％， n＝3）. After modeling， except for blank group， other groups suffered from loose stools， thin body and reduced food intake， and the body weight and serum level of D-xylose were decreased significantly compared with blank group （P＜0.01）. After last medication， above symptoms of administration groups were improved to different extents. Except for model group， body weight and serum contents of D-xylose in other groups were increased significantly than those before modeling or before medication （P＜0.05 or P＜0.01）. Compared with blank group， body weight and serum content of GAS were decreased significantly in model group， while serum content of VIP was increased significantly （P＜0.01）. Compared with model group， body weight of Shengmaiyin medium-dose group and Shengmaiyin polysaccharide low-dose and high-dose groups， serum contents of D-xylose and GAS in Shengmaiyin medium-dose and high-dose groups and Shengmaiyin polysaccharide low-dose and medium-dose groups were increased significantly， while serum contents of VIP in Shengmaiyin groups and Shengmaiyin polysaccharide low-dose and medium-dose groups were all decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS： The optimized extraction technology of Shengmaiyin polysaccharide is stable and feasible. Shengmaiyin and its polysaccharide contribute to the recovery of intestinal function of spleen deficiency model rat， the effects of which may be associated with the secretion regulation of GAS and VIP.