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Objective To evaluate the effect of Ji Tang Zhi on glucose metabolism in insulin resistance (IR) HepG 2 cell line,and to explore the related mechanism.Methods The HepG2 cells were incubated in culture medium addition of 10-7 mol/L insulin for 24 h to establish the IR cell model.Effect of Ji Tang Zhi on rate of glucose absorption in HepG2 cell was detected by the method of glucose oxidase-peroxidase (GOD-POD).We performed an MTT assay to determine cytotoxicity effects of Ji Tang Zhi on HepG2 cell line.The expression of p-IRS-1 Ser307,PI3K and GLUT-4 were detected by Western blotting.Results Incubated with 10-7 mol/L insulin for 24 h,the insulin resistance cell model had been built.Compared with model group,the rate of glucose absorption of cell treated with JTZ (30 ～ 120 μg/mL) was significantly improved.According to model cells,the expression of GLUT-4 and PI3K decreased significantly compared to control cells.While the expression of p-IRS-1 Ser 307 was inhibited and GLUT-4 and PI3K expression were increased in IR cells after treated with JTZ (30 ～ 120 μtg/mL).Conclusion JTZ exert beneficial effects on hyperglycosemia in IR cell line possibly through regulating the levels of GLUT-4,p-IRS-1 Ser307 and PI3K in HepG2 cell.
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Objective To explore the effects of water extract from Jiangtang Decoction (WEJTD) on PI3K/Akt signal pathway of skeletal muscle metabolism in KK-Ay diabetic mice.Methods Totally 50 KK-Ay mice were randomly divided into five groups:model group,metformin (positive drug,250 mg/kg) group,WEJTD low,medium,and high dose (2,4,and 8 g/kg) group,with 10 C57BL/6J mice as normal group.The relative drugs were ig administered once a day for 12 weeks,and mice in control group and model group were perfused with distilled water of equal volume.After 12 weeks' oral administration,mice were executed to separate serum,serum insulin level was detected by ELISA kit method;RNA was extracted from muscle tissue by Trizol,and real-time PCR were used to detect the level of PI3K,Akt,GLUT-4,GSK-3β,GS and IRS-1 mRNA.Results WEJTD can down-regulate concentration of insulin in serum and GSK-3β mRNA in skeletal muscle (P ＜ 0.05 and 0.001),and down-regulate mRNA of PI3K,Akt,IRS-1,GLUT-4,and GS in skeletal muscle (P ＜ 0.05,0.01,and 0.001).Conclusion WEJTD decreased glycogen deposition and stimulated glucose transport in skeletal muscle through upregulation of PI3K/Akt signaling pathway.
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Objective: To evaluate the effect of low-dose insulin [1 U/(kg·d)] in combination with selenium [180 g/(kg·d)] on general physiological parameters and glucose transporter (GLUT4) level in skeletal muscle of streptozotocin (STZ)-induced diabetic rats. Methods: Diabetic rats were treated with insulin, selenium, and insulin and selenium in combination for four weeks. The level of blood glucose was determined using One Touch SureStep Blood Glucose meter and the level of GLUT4 in skeletal muscle was examined by immunoblotting and immunohistochemistry. Results: Our data showed that insulin in combination with selenium could significantly lower blood glucose level and restore the disturbance in GLUT4 level in skeletal muscle. Treatment with insulin was only partially effective in restoring diabetic alterations. Conclusion: It can be concluded that there is a synergistic action between insulin and selenium, and that treatment of diabetic rats with combined doses of insulin and selenium is effective in the normalization of blood glucose level and correction of altered GLUT4 distribution in skeletal muscle of diabetic rats.
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Objective To evaluate the effect of low-dose insulin [1 U/(kg · d)] in combination with selenium [180 g/(kg · d)] on general physiological parameters and glucose transporter (GLUT4) level in skeletal mnscle of streptozotocin (STZ)-induced diabetic rats. Methods Diabetic rats were treated with insulin, selenium, and insulin and selenium in combination for four weeks. The level of blood glucose was determined using One Tonch SnreStep Blood Glucose meter and the level of GLUT4 in skeletal muscle was examined by immunobiotting and immnnohistochemistry. Results Our data showed that insulin in combination with selenium could significantly lower blood glucose level and restore the disturbance in GLUT4 level in skeletal muscle. Treatment with insulin was only partially effective in restoring diabetic alterations. Conclusion It can be concluded that there is a synergistic action between insulin and selenium, and that treatment of diabetic rats with combined doses of insulin and selenium is effective in the normalization of blood glucose level and correction of altered GLUT4 distribution in skeletal mnscle of diabetic rats.
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Objective To acquire glucose transporter 4 (GLUT4) cDNA from tissues of human muscle by RT-PCR, and to clone and express GLUT4 cDNA in E.coli. Methods GLUT4 cDNA primers were designed first and ascertained by detecting through Genbank on NCBI and DNA Star, then by using specific primers, the subjective cDNA segment was acquired by RT-PCR from human tissue. After that, it was cloned into cloning vector of pGEM-3zf(-) and sequenced automatically. Finally the subjective cDNA was cloned into vector of pBV220 and expressed in E.coli. Results The desired DNA could be acquired from tissues of human muscle by RT-PCR using special primers, the acquired cDNA fragment could be cloned into vector of pGEM-3zf(-) and sequenced. The GLUT4 cDNA sequence was highly conserved. GLUT4 cDNA could be expressed in E.coli, too. Conclusion The entire GLUT4 cDNA can be acquired from human muscular tissue by RT-PCR, and it can be expressed in E.coli.