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AIM：To analyse sequences of p62dok amino acid and cDNA and to investigate p62dok tyrosine phosphorylation and its relation with p21ras GAP. METHODS：The purified p62dok was extracted from CHO/IR cells. The peptide sequence of p62dok was carried out on a high performance analyzer. PCR was performed with the primers designed from the sequence of p62dok amino acid. Western blot and immunoprecipitation were used to identify tyrosine phosphorylation of p62dok and the binding of p62dok with p21ras GAP. RESULTS：The p62dok cDNA is a 1863 bp sequence and code 481 amino acid with 15 tyrosine residues and a putative pleckstrin homology domain. The p62dok protein is rich in PxxP motif. The tyrosine-phosphorylated p62dok can bind p21ras GAP. CONCLUSION：Perhaps p62dok is a new signaling molecule and play an important role in insulin signaling networks through RAS/MAPK pathway.
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AIM and METHODS: The protective effects of multi-enzyme Ⅱ was studied on cultured endothelial cells which was injuried by hyperlipidemia serum. RESULTS: Hyperlipidemia serum increased ICAM-1 expression on the surface of endothelial cells, and decreased NO- 2 release significantly (P
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AIM: To study the effect of thyroid hormone on the expressional change of myosin heavy chain(MHC) gene in cardiomyocyte induced by angiotensinⅡ(AngⅡ) and its potential mechanism. METHODS: Cardiac myocyte was cultured according to the method of Simpson. 10 -8 mol/L T_3 and 10 -7 mol/L AngⅡ were added to the culture medium,respectively or synchronously. After 48 h,the expression of ? and ?-MHC mRNA in myocytes were detected by RT-PCR. The protein kinase C activation were detected by PepTag non-radioactive PKC assay. The incorporation of -Leucine and -thymine to test the protein and DNA synthesis in myocytes were also performed. RESULTS: AngⅡalone increased the incorporation of -Leucine of myocytes while it had no effect on the incorporation of -thy mine. The expression of ?-MHC mRNA was increased and the expression of ?-MHC mRNA was decreased significantly at the condition of AngⅡ. The enhanced PKC activation was induced by AngⅡalso. When AngⅡand T_3 were added to the culture medium synchronously,though the incorporation of -leucine and -thymine were not changed compared with AngⅡ treated alone. The ?-MHC mRNA expression was increased and the ?-MHC mRNA expression was decreased significantly. The PKC activation of the myocytes also was decreased. CONCLUSIONS: T_3 inhibited the expressional change of myosin heavy chain gene in cardiac myocytes induced by AngⅡ. The effect of T_3 on the change of PKC activation in cardiac myocytes may be one of its mechanisms.
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AIM: To investigate the effects of sodium ferulate on cholesterol and triglyceride metabolism in atherosclerosis with hyperlipidemia.METHODS: The rabbit model of atherosclerosis was produced by feeding high lipid forages.RAW264.7 foam cell and HepG2 injured cell models were established by incubation with oxidized low density lipoprotein(ox-LDL).The atherosclerotic plaque area was measured,and serum lipids were detected.The cellular lipid accumulation was examined by oil red O staining.The cellular contents of total cholesterol and cholesterol ester were quantified by high performance liquid chromatography.The hepatic lipase(HL) mRNA expression was determined by RT-PCR.RESULTS:(1) Compared with hyperlipid group,the aorta atherosclerosis plaque area and the serum triglyceride level were significantly decreased in sodium ferulate-treated rabbits,but the serum cholesterol level showed little change.(2) Compared with ox-LDL group,the HL mRNA expression in HepG2 cells was enhanced significantly in sodium ferulate-treated group,but the cellular contents of total cholesterol and cholesterol ester in RAW264.7 foam cells showed little change.CONCLUSION: Sodium ferulate inhibits the formation of atherosclerotic plaque in high-cholesterol-fed rabbits aorta.This antiatherosclerotic function may reduce serum triglyceride level through enhancing the expression of HL mRNA without influencing serum cholesterol level and foam cell formation.
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AIM:To analyse sequences of p62 dok amino acid and cDNA and to investigate p62 dok tyrosine phosphorylation and its relation with p21 ras GAP. METHODS:The purified p62 dok was extracted from CHO/IR cells. The peptide sequence of p62 dok was carried out on a high performance analyzer. PCR was performed with the primers designed from the sequence of p62 dok amino acid. Western blot and immunoprecipitation were used to identify tyrosine phosphorylation of p62 dok and the binding of p62 dok with p21 ras GAP. RESULTS:The p62 dok cDNA is a 1863 bp sequence and code 481 amino acid with 15 tyrosine residues and a putative pleckstrin homology domain. The p62 dok protein is rich in PxxP motif. The tyrosine-phosphorylated p62 dok can bind p21 ras GAP. CONCLUSION:Perhaps p62 dok is a new signaling molecule and play an important role in insulin signaling networks through RAS/MAPK pathway.
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AIM: The effects of BDM on isolated rat heart in cold cardioplegia were studied METHODS: Rat heart were subjected to cold cardioplegia at 4℃ for 8, 18 and 24 h Then each heart was perfused (90 cm H 2O) in Langendorff model at 37℃ for 40 min In the high K + group( n =24) the hearts were preserved in St Thomas cardioplegic solution, in BDM group( n =24) hearts were preserved in K-H solution with BDM 30 mmoL/L RESULTS: After 18 h, heart rate and the coronary flow in BDM group were significantly higher than in high K + group( P