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Potential protection against the neurotoxic damages of high levels of fluoride on rats and SH-SY5Y cells by extract of Ginkgo biloba leaves, as well as underlying mechanisms, were examined.The rats were divided randomly into 4 groups, i.e., control, treatment with the extract (100 mg/kg body weight, gavage once daily), treatment with fluoride (50 ppm FThe rats with prolong treatment of fluoride exhibited dental fluorosis, the increased contents of fluoride in brains and urine and the declined ability of learning and memory. In the hippocampus of the rats and SH-SY5Y cells exposed to fluoride, the levels of ROS, MDA, apoptosis, 8-OHdG and the protein expressions of histone H2A.XGinkgo biloba extract attenuated neurotoxic damages induced by fluoride exposure to rats and SH-SY5Y cells and the underlying mechanism might involve the inhibition of PARP-1 and the promotion of SIRT1.

Three new (1-3) and four known (4-7) compounds were isolated from the stems of Baccaurea ramiflora. By analysis of 1D, 2D NMR, and MS data, the new compounds were identified as 4'-O-(6- O-vanilloyl)-beta-D-glucopyranosyl tachioside D (1), 6'-O-vanilloylpicraquassioside D (2), and 6'-O-vanilloylicariside B(5) (3). Compound 1 exhibited significant DPPH radical-scavenging activity, with an IC(50) value of 36.9 microM, while compound 4 revealed weak antioxidant activity against H (2)O(2)-induced impairment in PC12 cells.

Eight new lignan glucosides, tarennanosides A-H (1-8, resp.), were isolated from the whole plant of Tarenna attenuata, together with three known compounds, fernandoside, (-)-lyoniresinol, and (-)-isolariciresinol. The planar structures of new compounds were elucidated mainly by analysis of physical and spectroscopic data, and the absolute configurations were determined by acid hydrolysis as well as CD spectroscopy. Compounds 1 and 2 exhibited potent antioxidant activities against H2O2-induced impairment in PC12 cells. Preliminary mechanism study by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method showed that these two compounds could act as radical scavengers.

To study insulino-mimetic effects of bis(alpha-furancarboxylato) oxovanadium (IV) (BFOV), a orally active antidiabetic vanadyl complex, on glucose uptake and lipogenesis in isolated rat adipocytes were determined by using 2-deoxy-D-[3H]-glucose and D-[3H]-glucose, respectively. Lipolysis was assayed by free fatty acids (FFA) released from isolated rat adipocytes treated with epinephrine. The results showed that BFOV, similar to insulin, concentration-dependently significantly enhanced the uptake of 2-deoxy-D-[3H]-glucose and the transformation from D-[3H]-glucose to lipid in isolated rat adipocytes, with the EC50 values of (0.31 +/- 0.08) mmol L(-1) and (0.49 +/- 0.12) mmol L(-1), respectively. Moreover, BFOV markedly inhibited FFA release from isolated rat adipocytes treated with epinephrine, and the IC50 value was (0.30 +/- 0.20) mmol L(-1). BFOV had insulino-mimetic effects such as enhancing glucose uptake and lipogenesis, as well as inhibiting lipolysis.

To study the effects of ephrinB2 gene transfection on the differentiation of bone marrow mesenchymal stem cells (BMSCs) into vascular endothelial cells.Wistar rat BMSCs were isolated by density gradient centrifugation and purified on the basis of their adhesion ability. The BMSCs were transfected with a lenti-virus vector encoding a constitutively active form of human ephrinB2 gene, and the cell markers including CD105, CD73, CD44, von Willebrand factor (VWF) and vascular growth factor receptor 2 (KDR) were detected using flow cytometry. The potential of ephrinB2-BMSCs for differentiation into osteoblasts and adipoblasts in vitro were tested, and the differentiation of the cells into endothelial-like cells was induced by culture in the presence of 2% fetal bovine serum and 50 ng/ml vascular endothelial growth factor.EphrinB2-BMSCs were positive for the markers CD105, CD73 and CD44, and negative for the typical endothelial markers like VWF and KDR, and retained high potentials for differentiation into osteoblasts and adipoblasts in vitro after cultivation in respective media. After induced differentiation, ephrinB2-BMSCs expressed VWF and KDR and showed greater ability of differentiation into vascular endothelial cells and formation of capillary structures on matrix gel than the BMSCs without transfection.EphrinB2 gene transfection efficiently promotes the differentiation of BMSCs into vascular endothelial cells. These genetically engineered cells provide valuable sources for new therapies of coronary heart disease.

Two novel chalcone constituents, tarennane (1) and tarennone (2), together with nine known compounds, were isolated from the whole plant of Tarenna attenuata. By analysis of physical and spectroscopic data, the structures of new compounds were elucidated as (E)-4-[3-(4-hydroxy-3-methoxyphenyl)-acryl]3,4,5-trimethoxycyclohexa-2,5-dienone (1) and 1,2-bis(3,5-dimethoxy-4-hydroxyphenyl)-3-hydroxypropan-1 -one (2). These two compounds were tested for antioxidant activities in the MTT and DPPH assays. Compound I revealed potent antioxidant activities against H2O2-induced impairment in PC12 cells, but neither of them showed DPPH radical-scavenging activity with lC(50) values of 181.1 and 210.3 mu M, respectively.

Six new mixed lignan-neolignans and 20 known compounds were isolated from the whole plant of Tarenna attenuata. By analysis of physical and spectroscopic data, the structures of the new compounds were elucidated as (1R,5R,6R)-6-{4-O-[2-(1-(4-hydroxy-3-methoxyphenyl))glycerol]-3,5-dimethoxyphenyl}-3,7-dioxabicyclo[3.3.0]octan-2-one (1), 5' '-methoxyhedyotisol A (2), 4' '-O-(8-guaiacylglycerol)buddlenol A (3), 5' '-methoxy-4' '-O-(8-guaiacylglycerol)buddlenol A (4), 4,6-dimethoxy-5-hydroxy-3-hydroxymethyl-2-(3,4,5-trimethoxyphenyl)-2,3-dihydrobenzofuran (5), and 7-O-ethylguaiacylglycerol (6). Compounds 1, 5, 6, and 8 showed potent antioxidant activities against H2O2-induced impairment in PC12 cells, and compounds 1, 2, 5, and 7 scavenged DPPH radical strongly with IC50 values of 72, 87, 45, and 55 microM, respectively.