ABSTRACT
Objective To establish an HPLC method for the content determination of morroniside, sweroside, paeoniflorin and loganin of Liuwei Dihuang Decoction and its Cornus Officinalis-Cortex Moutan couple; To discuss the relationship between the whole prescription and the couple of main pharmacodynamic components. Methods The HPLC method was used at Hypersile C18 column (4.6 mm × 250 mm, 5 μm); the mobile phase consisted of methanol-water (24:76); the detective wavelength was 236 nm; the flow rate was 1.0 mL/min; the column temperature was 30 ℃. Results The linear ranges of morroniside, sweroside, paeoniflorin and loganin were among 0.480–7.680 μg (r=0.999 3), 0.103–1.650 μg (r=0.999 5), 0.120–1.920 μg (r=0.999 1) and 0.227–3.630 μg (r=0.999 7), respectively. The average recovery rates and RSD were 102.79%, 102.29%, 100.99%, 102.48%, and 1.73%, 1.48%, 1.32%, 0.75%, respectively. The contents of morroniside, sweroside and paeoniflorin in Liuwei Dihuang Decoction were slightly higher than that in Cornus Officinalis - Cortex Moutan couple, and the contents of loganin were almost the same. Conclusion The method is simple, stable, accurate and reproducible. It can be used for content determinate of glycosides in Liuwei Dihuang Decoction and Cornus Officinalis-Cortex Moutan couple. Cornus Officinalis-Cortex Moutan couple has the glycosides with tonifying kidney effect of Liuwei Dihuang Decoction.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the role of c-Jun N-terminal kinase (JNK) signal transduction pathway in the rats of nonalcoholic fatty liver disease (NAFLD).</p><p><b>METHODS</b>Sixty four Sprague-Dawley rats were randomly divided into four groups: 8-week control group (NG8w), 12-week control group (NG12 w), 8-week high-fat diet (HG8w), and 12-week high-fat diet group (HG12w), with 16 rats in each group. Glucose infusion rate (GIR) was tested by euglycemic hyperinsulinemic clamp; aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC), free fatty acid (FFAs), fast insulin (FIns), tumor necrosis factor alpha (TNF alpha), superoxide dismutase (SOD) and malondialdehyde (MDA) were tested by biochemistry automatic analyzer or RIA; The expression of JNK1, insulin receptor substrate-1 (IRS-1), phospho-IRS-1 Ser307 (p-IRS-1 Ser307), Protein kinase B (PKB) and phospho-PKB Ser473 (p- PKB Ser473) were detected by Western blot.</p><p><b>RESULTS</b>Compared to control group, body weight, liver index, serum levels of ALT, AST, TG, TC, FIns, FFAs, TNF alpha, and TC, TG FFAs, MDA in liver homogenates were increased, while the level of SOD, and GIR were decreased. The expression of JNK1 protein and p-IRS-1 Ser307 in liver tissue was up-regulated, while expression of p-PKB Ser473 was decreased (P < 0.05). A positive correlation was found between the expression intensity of JNK1 and IR (Pearson correlation: 0.718, P < 0.01).</p><p><b>CONCLUSION</b>The high-fat could induce the expression of JNK1, which in turn modulates the phosphorylation of proteins in the insulin signaling pathway, and induces insulin resistant.</p>