ObjectiveTo investigate the role of peroxisome proliferator-activated receptor gamma (PPARγ)/Caspase-8/Caspase-3 signaling pathway in the development of hyperlipidemia in rats.Methods 60 healthy male SD rats 〔4-week old,weight (110 ± 10) g〕 were randomly divided into control group,high-fat diet group,folic acid group,vitamin B12 group,folic acid and vitamin B12 group.After one week's feeding for adaptability,the groups of foloc acid,vitamine B12 and foloc acid + vitamineB12 were dealt with intraperitoneal injection of folic acid (0.5 mg/d),vitamin B12 (0.05mg/d),and folic acid (0.5 mg/d) plus vitamin B12 (0.05 mg/d),respectively,and fed with high fat diet simultaneously.Control group was dealt with intraperitoneal injection of normal saline (0.5 ml/d)and fed with normal diet.High-fat diet group was only fed with high fat diet.Reverse transcription polymerase chain reaction (RT-PCR) was used to measure the mRNA level of PPARy,Caspase-8 and Caspase-3 in aorta abdominalis dissected at 17 weekends.Results Folic acid alone or jointed with vitamin B12 could effectively increase the level of PPARγ,while decrease the mRNA levels of Caspase8 and Caspase-3 as compared with high-fat diet group (P＜0.05),and folic acid plus vitamin B12 was more effective than folic acid alone (P＜0.05).Conclusions Folic acid alone or joined with vitamin B12 can improve the mRNA levels of PPARγ,Caspase-8 and Caspase-3 in vascular wall to protect endothelial injury from hyperlipidemia.

Objective To investigate the myocardial protection of adiponectin (ADP) /adiponectin receptor 1 (ADPR1) related-signal pathway in rats with limb ischemic preconditioning.Methods Thirty SD male rats were randomly divided into sham-operation group,myocardial ischemia reperfusion injury (MIRI) group,limb ischemic preconditioning (LIPC) group,LY294002 (the PI3-specific inhibitor) pretreatment group and LY294002+LIPC group (n=10 each).The mRNA level of myocardial ADP and ADPR1,the protein expressions of phosphatidylinositol 3-kinase (PI3k)phosphorylated Akt (p-Akt) were determined by RT-PCR and Western blot,respectively. Results As compared with sham-operation group,the mRNA levels of ADP and ADPR1 in MIRI group were significantly decreased (0.53 ± 0.07 vs.0.74 ± 0.08 and 0.52 ± 0.02 vs.0.72 ± 0.04,P＜0.05).Compared with MIRI group,the mRNA levels of ADP (0.72±0.21) and ADPRI (0.80±0.023) in LIPC group were increased,ADP(0.49±0.07) and ADPR1 (0.52± 0.02) mRNA were decreased in LY294002 group (both P＜0.05),but there were no difference in ADP(0.70±0.16) and ADPR1(0.78±0.05) mRNA between LY294002+LIPC group and MIRI group.The protein levels of Pl3k and p-Akt were lower in MIRI group than in sham-operation group (3.85±0.23 vs.2.83±0.22and 3.77±0.32 vs.2.66±0.29,P＜0.05).In contrast to MIRI group,the yield of PI3k (2.65±0.32)and p-Akt(2.26±0.27) protein (P＜0.05) were increased in LIPC group,but there were unproductive protein of PI3k (3.75 ± 0.65) and p-Akt (4.01 ± 0.71) in LY294002 group with no differences versus the levels of PI3k (3.23 ± 0.48) and p-Akt (3.17 ± 0.54) in LY294002 + LIPC group. Conclusions Limb ischemic preconditioning may protect myocardium by promoting serum adiponectin levels,improving myocardial mRNA expressions of ADP and ADPR1,activating the ADP/PI3k/Akt signaling pathway in reperfusion injury.

BACKGROUND: Nowadays, biological tissue engineering is a growing field of research. Biocompatibility is a key indicator for measuring tissue engineering biomaterials, which is of great significance for the replacement and repair of damaged tissues. METHODS: In this study, using gelatin, carboxymethyl chitosan, and sodium alginate, a tissue engineering material scaffold that can carry cells was successfully prepared. The material was characterized by Fourier transforms infrared spectroscopy. In addition, the prepared scaffolds have physicochemical properties, such as swelling ratio, biodegradability.we observed the biocompatibility of the hydrogel to different adult stem cells (BMSCs and ADSCs) in vivo and in vitro. Adult stem cells were planted on gelatin-carboxymethyl chitosan-sodium alginate (Gel/SA/CMCS) hydrogels for 7 days in vitro, and the survival of stem cells in vitro was observed by live/died staining. Gel/SA/CMCS hydrogels loaded with stem cells were subcutaneously transplanted into nude mice for 14 days of in vivo culture observation. The survival of adult stem cells was observed by staining for stem cell surface markers (CD29, CD90) and Ki67. RESULTS: The scaffolds had a microporous structure with an appropriate pore size (about 80 lm). Live/died staining showed that adult stem cells could stably survive in Gel/SA/CMCS hydrogels for at least 7 days. After 14 days of culture in nude mice, Ki67 staining showed that the stem cells supported by Gel/SA/CMCS hydrogel still had high proliferation activity. CONCLUSION Gel/SA/CMCSs hydrogel has a stable interpenetrating porous structure, suitable swelling performance and degradation rate, can promote and support the survival of adult stem cells in vivo and in vitro, and has good biocompatibility. Therefore, Gel/SA/CMCS hydrogel is a strong candidate for biological tissue engineering materials.