A method of high performance liquid chromatographic separation of clausenamide enantiomers with chiral-AGP(α_1-acid glycoprotein) stationary phases has been established.The absolute configurations of(-)clausenami...A method of high performance liquid chromatographic separation of clausenamide enantiomers with chiral-AGP(α_1-acid glycoprotein) stationary phases has been established.The absolute configurations of(-)clausenamide and(+)clausenamide are 3S, 4R,5R,6S and 3R,4S,5S,6R,respectively.The present method has been used to analyze the(-)clausenamide and(+)clausenamide and its analogues such as the major metabolite and synthetic derivatives of clausenamide.展开更多
A normal phase enantioselective high performance liquid chromatographic method was developed for enantiomeric resolution of Ezetimibe it reduces the overall delivery of cholesterol to the liver. The enantiomers of Eze...A normal phase enantioselective high performance liquid chromatographic method was developed for enantiomeric resolution of Ezetimibe it reduces the overall delivery of cholesterol to the liver. The enantiomers of Ezetimibe were resolved on a Chiral Pak AS-H (250 × 4.6 mm, 5 μm) column using a mobile phase system containing n-Hexane, etha-nol, 2-Propanol and Trifloroacetic acid (84:12:4:0.1 v/v). The resolution between enantiomers was found to be more than 2.0. The limit of detection and limit of quantification of (R)-enantiomer were found to be 0.2 μg/mL and 0.5 μg/mL, respectively, for 10 μL injection volume. The sample solution and mobile phase were found to be stable for at least 48 h. The final optimized method was successfully applied to separate (R)-enantiomer from Ezetimibe and was proven to be reproducible and accurate for the quantitative determination of (R)-enantiomer in bulk drugs.展开更多
Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption,...Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.展开更多
文摘A method of high performance liquid chromatographic separation of clausenamide enantiomers with chiral-AGP(α_1-acid glycoprotein) stationary phases has been established.The absolute configurations of(-)clausenamide and(+)clausenamide are 3S, 4R,5R,6S and 3R,4S,5S,6R,respectively.The present method has been used to analyze the(-)clausenamide and(+)clausenamide and its analogues such as the major metabolite and synthetic derivatives of clausenamide.
文摘A normal phase enantioselective high performance liquid chromatographic method was developed for enantiomeric resolution of Ezetimibe it reduces the overall delivery of cholesterol to the liver. The enantiomers of Ezetimibe were resolved on a Chiral Pak AS-H (250 × 4.6 mm, 5 μm) column using a mobile phase system containing n-Hexane, etha-nol, 2-Propanol and Trifloroacetic acid (84:12:4:0.1 v/v). The resolution between enantiomers was found to be more than 2.0. The limit of detection and limit of quantification of (R)-enantiomer were found to be 0.2 μg/mL and 0.5 μg/mL, respectively, for 10 μL injection volume. The sample solution and mobile phase were found to be stable for at least 48 h. The final optimized method was successfully applied to separate (R)-enantiomer from Ezetimibe and was proven to be reproducible and accurate for the quantitative determination of (R)-enantiomer in bulk drugs.
基金Changshu Science and Technology Plan(Social Development)Project(No.CS202130)Key Project of Changshu No.2 People’s Hospital(No.CSEY2021007)。
文摘Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.