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The methanol fraction of an ethanolic extract from the roots of Polygala tenuifolia Willd. showed antagonistic action on neurotoxicity induced by glutamate and serum deficiency in PC12 cells. Bioassay-guided fractionation led to the isolation of six new triterpenoid saponins, onjisaponins V - Z, and Vg ( 1 - 6), together with ten known saponins ( 7 - 16). The structures of 1 - 6 were elucidated by spectroscopic and chemical methods. Screening results indicated that compounds 1 - 16 showed neuroprotective effects against serum deficiency and glutamate at the concentration of 10 (-5) mol/L.

In dose range of 200-800 mg, multiple-dose oral baicalein administration was safe and well tolerated, dose proportionality was inconclusive, and no serious accumulation of baicalein was observed.

We have produced and characterized polyclonal antiidiotypic antibodies (anti-ids) that mimic the antigenic structures of gp53 from bovine viral diarrhoea virus (BVDV). In this study, the anti-ids were used to identify cell receptors for BVDV. The anti-ids bound specifically to bovine cells, as determined by flow cytometric analysis, and inhibitory binding assays showed that they bound to the cell surface receptors for BVDV. A cell surface protein with an M,, of approximately 50K was immunoprecipitated by the anti-ids from MDBK cells; this was blocked by preincubation of cell lysate with BVDV. This indicates that the 50K protein might be a specific receptor for BVDV gp53. Thirteen BVDV strains were used to evaluate inhibition ofanti-id binding to MDBK cells and inhibition of BVDV infection of anti-id-treated MDBK cell monolayers. Results demonstrated that both processes were inhibited to varying degrees depending on virus strain. The results suggested that multiple receptors for BVDV attachment may exist on MDBK cells, and that different virus strains do not have the same receptor.

Aim: The aim of this study was to investigate the cognition-enhancing activity and underlying mechanisms of a triterpenoid saponin (polygalasaponin XXXII, PGS32) isolated from the roots of Polygala tenuifolia Willd. Methods: The Morris water maze was used to evaluate the spatial learning and memory of mice. To detect the basic properties of synaptic transmission and long-term potentiation (LTP) in the dentate gyrus of rats, electrophysiological recordings were made of evoked potentials. Western blotting analysis and immunofluorescence assays were used to determine the phosphorylation of extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), synapsin I and the expression of brain derived neurotrophic factor (BDNF). Results: When administered at 0.125, 0.5, or 2 mg/kg, PGS32 could significantly prevent scopolamine-induced cognitive impairments in mice. Intracerebroventricular (icv) administration of PGS32 greatly enhanced basic synaptic transmission in the dentate gyrus of rats and induced LTP. In primary hippocampal neurons, as well as in the hippocampus of maze-trained mice, PGS32 activated the mitogen-activated protein (MAP) kinase cascade by promoting phosphorylation of ERK, CREB and synapsin I. The expression of BDNF was also greatly enhanced in the hippocampus. Conclusion: Our findings suggest that PGS32 can improve hippocampus-dependent learning and memory, possibly through improvement of synaptic transmission, activation of the MAP kinase cascade and enhancement of the level of BDNF. Therefore, PGS32 shows promise as a potential cognition-enhancing therapeutic drug.

Phospholipase C epsilon 1 (PLCE1) plays an important role in cell growth, differentiation and oncogenesis. An increasing number of individual studies have investigated the association between PLCE1 rs2274223 polymorphism and cancer risk, but the conclusions are inconclusive. To obtain a comprehensive conclusion, we performed a meta-analysis of 22 studies with 13188 cases and 14666 controls. The pooled results indicated that PLCE1 rs2274223 A > G polymorphism was associated with an increased risk of overall cancer (G vs. A: OR = 1.15, 95% CI = 1.06–1.25; GG vs. AA: OR = 1.30, 95% CI = 1.10–1.55; GA vs. AA: OR = 1.18, 95% CI = 1.08–1.30; GG/GA vs. AA: OR = 1.20, 95% CI = 1.08–1.32; GG vs. GA/AA: OR = 1.22, 95% CI = 1.04–1.42). The stratification analysis showed the polymorphism was significantly associated with an increased risk of esophageal squamous cell carcinoma (ESCC) other than gastric cancer (GC), especially among the subgroups of Asian, high quality score, sample size > 1000 and the studies consistent with Hardy-Weinberg equilibrium (HWE). This meta-analysis demonstrated that PLCE1 rs2274223 A > G polymorphism may be associated with increased susceptibility to cancer, especially for ESCC. However, due to the substantial heterogeneities across the studies, the conclusion might be not conclusive that need more studies to confirm.

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