Gypenosides Inhibits Xanthine Oxidoreductase and Ameliorates Urate Excretion in Hyperuricemic Rats Induced by High Cholesterol and High Fat Food (Lipid Emulsion).

BACKGROUND The aim of this study was to study the effects of gypenosides (GPS) on lowering uric acid (UA) levels in hyperuricemic rats induced by lipid emulsion (LE) and the related mechanisms. GPS are natural saponins extracted from Gynostemma pentaphyllum. MATERIAL AND METHODS Forty-eight male SD rats were randomly divided into six groups: normal, model, two positive controls, and two GPS treated groups (two different doses of GPS). The normal group rats were fed a basic diet, and the other rats were orally pretreated with LE. Urine and blood were collected at regular intervals. Full automatic biochemical analyzer was used to detect the concentration levels of serum UA (SUA), serum creatinine (SCr), BUN, and urine UA (UUA), and urine creatinine (UCr) and fractional excretion of UA (FEUA). ELISA kits were used to detect enzymes activities: xanthine oxidase (XOD), adenosime deaminase (ADA), guanine deaminase (GDA), and xanthine dehydrogenase (XDH). Immunohistochemistry was used to observe kidney changes and protein (URAT1, GLUT9, and OAT1) expression levels. RT-PCR was used to detect the relevant mRNA expression levels. RESULTS Treatment with GPS significantly reduced the SUA, prevented abnormal weight loss caused by LE, and improved kidney pathomorphology. Treatment with GPS also decreased the levels of XOD, ADA, and XDH expression, increased the kidney index and FEUA, downregulated URAT1 and GLUT9 expression and upregulated OAT1 expression in the kidney. CONCLUSIONS GPS may be an effective treatment for hyperuricemia via a decrease in xanthine oxidoreductase through the XOD/XDH system; and via an increase in urate excretion through regulating URAT1, GLUT9, and OAT1 transporters.

[Protective Effect of Total Flavonoids from Carya cathayensis Leaf on Cultured H9C2 Cardiomyocytes During Hypoxia / Reoxygenation Injury].

Objective: To study the protective effect of total flavonoids from Carya cathayensis leaf on cultured H9C2 cardimyocytes during hypoxia / reoxygenation( H / R) injury. Methods: Co Cl2 was used to induce the H / R injury model in H9C2 cells at different concentrations,different H / R time. Total flavonoids from Carya cathayensis leaf was added into culture medium with final concentration of2. 5,5 and 10 µg / m L before H / R. Lactate dehydrogenase( LDH), Malondialdehyde( MDA) content, Superoxidedimutase( SOD) activity in the bathing medium were assayed for the evaluation of myocardial cell injury. Myocardial cell viability was detected by the MTS assay kit. Apoptotic changes in H9C2 cells were observed by using Hoechst-PI staining and flow cytometry analysis. The expression of HIF-1αprotein was detected by Western blot. Results: Using 1 200 µmol / L Co Cl2 to hypoxia the cells for 18 h and then reoxygenation for 2 h were the best condition of H / R injury model. Compared with model group,the cells treated with total flavonoids from Carya cathayensis leaf could decrease the activity of LDH and the content of MDA, while increased the activity of SOD. Moreover, they could regulate the expression of HIF-1α protein to normal level. Conclusion: It is suggested that total flavonoids from Carya cathayensis leaf has a protective effect on H9C2 cardiomyocyte during H / R injury. The mechanism may be relate to enhancing the capability of the cell clearing the oxygen free radial, decreasing the production of lipid peroxidation and reducing apoptosis.

[Study on anti-angiogenesis effect of three curcumin pigments and expression of their relevant factors].

To study the in vitro anti-angiogenesis effect of three curcumin pigments (curcumin, demethoxycurcumin, bisdemethoxycurcumin). In the study, the inhibitory effect of the three curcumin pigments on proliferation of HUVEC cells induced by OX-LDL and the effect on migration of HUVEC cells were detected. The effect on neovascularization was observed by chorioallantoic membrane (CAM) test. The effect on cell adhesion factors ICAM-1 and VCAM-1 of HUVECs were tested by Real-time RT-PCR. It was found that the three curcumins could inhibit the proliferation of HUVEC cells induced by OX-LDL within the dosage range 4, 8, 16 mg x L(-1), with a dose-dependence. The proliferative effect of curcumins on HUVECs was greater than the other two derivatives (P < 0.01). All of the three curcumin pigments inhibited the migration of HUVEC cells and the angiogenesis of chick chorioallantoic membrane (CAM). The migration inhibition rate of curcumins at middle and high concentrations was greater than the other two (P < 0.01). All of the three curcumin could down-regulate the expression of VEGF and ICAM-1, and curcumins showed more obvious effect in down-regulating VEGF than demethoxycurcumin and bisdemethoxycurcumin(P < 0.01); Bisdemethoxycurcumin showed the most significant effect in down-regulating ICAM-1 (P < 0.01). All of the three showed no remarkable effect on expression of VCAM-1, and only bisdemethoxycurcumin showed the down-regulating effect (P < 0.05). According to the findings, all of the three curcumin pigments could resist angiogenesis by inhibiting proliferation and migration of endothelial cells and down-regulating the expression of VEGF and adhesion molecules ICAM-1.

Sodium arsenite induces ROS-dependent autophagic cell death in pancreatic ß-cells.

Inorganic arsenic is a worldwide environmental pollutant. Inorganic arsenic's positive relationship with the incidence of type 2 diabetes mellitus arouses concerns associated with its etiology in diabetes among the general human population. In this study, the inhibitor of autophagosome formation, 3-methyladenine, protected the cells against sodium arsenite cytotoxicity, and the autophagy stimulator rapamycin further decreased the cell viability of sodium arsenite-treated INS-1 cells. These finding suggested the hypothesis that autophagic cell death contributed to sodium arsenite-induced cytotoxicity in INS-1 cells. Sodium arsenite increased the autophagosome-positive puncta in INS-1 cells observed under a fluorescence microscope, and this effect was confirmed by the elevated LC3-II levels detected through Western blot. The LC3 turnover assay indicated that the accumulation of autophagosomes in the arsenite-treated INS-1 cells was due to increased formation rather than impaired degradation. The pretreatment of INS-1 cells with the ROS inhibitor NAC reduced autophagosome formation and reversed the sodium arsenite cytotoxicity, indicating that sodium arsenite-induced autophagic cell death was ROS-dependent. In summary, the precise molecular mechanisms through which arsenic is related to diabetes have not been completely elucidated, but the ROS-dependent autophagic cell death of pancreatic ß-cells described in this study may help to elucidate the underlying mechanism.

Cardamonin inhibits angiotensin II-induced vascular smooth muscle cell proliferation and migration by downregulating p38 MAPK, Akt, and ERK phosphorylation.

Cardamonin is a chalconoid isolated from various herbs, such as Alpinia katsumadai and Carya cathayensis Sarg. This study examined the effect of cardamonin on angiotensin II (Ang II)-induced proliferation and migration in rat vascular smooth muscle cells (VSMCs) as well as its underlying mechanisms. The results showed that cardamonin significantly inhibited Ang II-induced proliferation and migration in rat VSMCs in a concentration-dependent manner. Moreover, cardamonin suppressed Ang II-induced phosphorylation of p38 MAPK, Akt, and extracellular regulated protein kinase (ERK). These findings indicate that the downregulation of p38 MAPK, Akt, and ERK phosphorylation might be, at least in part, involved in cardamonin-suppressed proliferation and migration induced by Ang II in rat VSMCs. As proliferation and migration of VSMCs play critical roles in the pathogenesis of atherosclerosis, cardamonin might be a potential candidate for atherosclerosis treatment.

Flavonoids from the leaves of Carya cathayensis Sarg. inhibit vascular endothelial growth factor-induced angiogenesis.

The total flavonoids (TFs) were isolated from the leaves of Carya cathayensis Sarg. (LCC), a well-known Chinese medicinal herb commercially cultivated in Tianmu Mountain district, a cross area of Zhejiang and Anhui provinces in China. Five flavonoids, i.e. cardamonin, pinostrobin chalcone (PC), wogonin, chrysin, and pinocembrin were the main components of the TFs. The TFs and these pure compounds suppressed vascular endothelial growth factor (VEGF)-induced angiogenesis as detected in the mouse aortic ring assay, and cardamonin showed the best effect among them. To further elucidate the mechanisms for suppressing angiogenesis of these flavonoids, assays of VEGF-induced proliferation and migration in human umbilical vein endothelial cells (HUVECs) were performed. The TFs, cardamonin, pinocembrin, and chrysin obviously suppressed both VEGF-induced HUVEC proliferation and migration. However, PC and wogonin not only slightly inhibited VEGF-induced proliferation but also remarkably suppressed those of migration in HUVECs. Our further study showed that cardamonin decreased the phosphorylation of ERK and AKT induced by VEGF with a dose-dependent manner in HUVECs. Our findings indicate that the TFs and these pure flavonoids may become potential preventive and/or therapeutic agents against angiogenesis-related diseases.