Advanced Materials Research Vols. 998-999

Abstract: Polycystic ovary syndrome (PCOS) is a major public health problem in reproductive-aged women worldwide, but the precise pathogenesis of PCOS remains unclear. Our previous study has clarified that hypoxia-inducible factor-1alpha (HIF-1α) mediated endthlin-2 (ET-2) signaling plays an important role in the ovulatory process in rats. Therefore, the present study used PCOS rat model to test the hypothesis that HIF-1α signaling is inhibited in ovaries during PCOS fromation. By the changed of bodyweight, ovarian histology and ovarian weight, PCOS rat model was further confirmed. And then the present study examined the changes of ET-2 and HIF-1α mRNA levels through real-time PCR finding the significant decrease of ET-2 mRNA level in PCOS rat ovaries was found, while HIF-1α mRNA significantly increased. However, by western blot analysis, the present study found HIF-1α protein expression was significantly decreased, which is consistent with ET-2 protein expression implying HIF-1α-medated ET-2 signaling is vital during PCOS formation. Moreover, the result of HIF prolyl hyodroxylase activity analysis found the decrease of HIF-1α protein may be caused through HIF protein degradation by the increased HIF prolyl hyodroxylase activity. Taken together, these results indicate that HIF-1α signaling is inhibited in PCOS rat model through increase of HIF prolyl hyodroxylase activity suggesting HIF-1α signaling plays an important role in the formation of PCOS. This HIF-1α-mediaged ET-2 expression may be on of the important mechanisms regulating PCOS formation in mammalian ovaries in vivo. Keywords: HIF-1α; ET-2; HIF prolyl hyodroxylase acitvity; polycystic ovary syndrome

Abstract: We present evidences demonstrating that overexpression of IRE1a inhibits chondrocyte differentiation, as revealed by reduced expression of Col,,SOX9, ColX, MMP-13, IHH, Runx2. Furthmore, IRE1a-mediated inhibition of chondrogenesis depends on its enzymatic activity, since its point mutant lacking enzymatic activity completely loses this activity. The RNase and Kinase domains of IRE1a C-terminal is necessary for its full enzymatic activity and inhibition of chondrocyte differentiation. Mechanism studies demonstrate that granulin-epithelin precursor (GEP),a growth factor known to stimulate chondrogenesis, induced IRE1a expression in chondrogenesis. In addition, IRE1a inhibits GEP-mediated chondrocyte differentiation as a negative regulator. Altered expression of IRE1a in chondrocyte hypertrophy was accompanied by altered levels of IHH and PTHrP.Collectively,IRE1a may be a novel regulator of chondrocyte differentiation by 1) inhibition GEP-mediated chondrocyte differentiation as a negative regulator; 2) promoting IHH/PTHrP signaling.

Abstract: Saponins from Rhizoma Panacis Majoris (SRPM), the bioactive component in Rhizoma Panacis Majoris, were reported to possess protective effects on brain injury, but the underlying mechanisms remain poorly understood. This study was performed to investigate the protective effects and possible mechanism of SRPM on cerebral ischemia/reperfusion (CI/R) injury. Neuroprotective effects of SPRM in CI/R mice was evaluated by infarct size, biochemical values, Nuclear factor erythroid 2-related factor 2 (Nrf2) and Bcl-2 family expressions. In the study, we found that SRPM exerted beneficially protective effects on CI/R injury, mainly scavenging oxidative stress-triggered overgeneration and accumulation of reactive oxygen species, improving the Nrf2-mediated antioxidant response: role of Nrf2 and Bcl-2 family expressions, and alleviating CI/R injury and cerebral cell death.

Abstract: The present study was to evaluate the effects of certain nutrients and environmental parameters on growth and production of polysaccharide of Hericium erinaceus with tofu whey. The effect of different carbon and nitrogen sources, temperature, pH and incubation period on the production of polysaccharide in flask cultures by H. erinaceus was investigated. Glucose and potato extract were found to be the most suitable carbon and nitrogen source, respectively. Optimum production of polysaccharide required glucose in the cultivation medium with a concentration of 8.0 g/L. On the other hand, the highest production of polysaccharide was obtained in a cultivation medium containing 12.0 g/L of potato extract. Furthermore, the incubation temperature at 27 °C, pH 5.5, rotation rate 180 and seven days of the incubation were found to be the optimum for maximum production of polysaccharide of H. erinaceus.

Abstract: PLK1 has been implicated in tumorigenesis and progression. The role of PLK1 in carcinogenesis has not been fully understood. In our study, we established PLK1-overexpressed stable transfectants in esophageal squamous cell carcinoma (ESCC) cells. Ectopic overexpression of PLK1 enhanced invasiveness of ESCC cells. Compared with the empty vector-transfected cells, PLK overexpression dramatically decreased expression of E-cadherin and increased expression of Vimentin in ESCC cells. Furthermore, Vimentin was also significantly increased at mRNA level in PLK overexpressed ESCC cells. These data suggest that PLK1 promotes invasion of ESCC cells by inducing EMT.

Abstract: Nacre composing the inner layer of mollusk shell is a typical product of biomineralization. While main components of the organics in nacre are proteins, which mediate its distinctive lamellate structure. Although kinds of nacre proteins have been reported, the whole process of nacre formation is still unclear—especially on molecular level. In this paper, homology, structure, classification and mineralization characters of nacre proteins are elaborated and summarized.

Abstract: Osteoarthritis (OA) is a degenerative joint disease that affects millions of people. Currently, there is no effective drug treatment for it. The purpose of this study is to investigate the chondroprotective effects of 5,7,3’,4’- tetramethoxyflavone in isolated cartilage chondrocytes cultured pre-treatment by IL-1β. The results showed that 5,7,3’,4’- tetramethoxyflavone could significantly down regulate the concentration of MMP-13, but up regulate the expression of TIMP-1, increase the proliferative activity of rat chondrocytes.

Abstract: In order to search for new structural modification strategies on quercetin, we have designed and synthesized a series of quercetin derivatives. Several novel quercetin derivatives displayed potent protect effect on H₂O₂-induced injury in PC12 cells. In the recent study, we investigated the effect of 3,3',4',5,7-pentahydroxyflavone 2-(3,4-dihydroxyphenyl)-3,5,7-trihydroxy-4H-1-benzopyran-4-one (HPS5) on the apoptosis of PC12 cells in vitro. We used neuronal PC12 cell line to study the regulation role of HPS5 in H₂O₂ induced cell apoptosis. MTT assay was used for detection the proliferation of PC12 cells upon H₂O₂ treatment. PC12 cell nuclear morphological change was detected with Hoechst 33258 staining. The antioxidative capacity was judged by SOD determinations. The protein levels of Bax and Bcl-2 were deteanined by Western blotting. Our results demonstrated that Quercetin derivatives HPS5 can prevent and protect against H₂O₂-induced injury in PC12 cells. Together, our studies provided new insights activities of quercetin, and may contribute to pharmacological study of quercetin in future research.

Abstract: Punica granatum L. Pomegranate has been traditionally used as a folk fruits for centuries in Oriental countries. It extract and subsequent fractions were used to evaluate antioxidant and related activities of Punica granatum L. It were extracted by 70% acetone, and then purified by HPD-400 macroporous adsorbent resins column. The aim of this study was to verify the antioxidant properties of acetone extracts of pomegranate pericarps and their lyophilized samples, and also to study the relationship between the activity and the contents of the tannins. The effects of natural extracts on microsomal lipid of mice liver and erythrocyte membrane lipid were examined. Vc/Fe²⁺, Cys/Fe²⁺induced microsomal lipid peroxidation, UV light induced erythrocyte membrane lipid peroxidation were measured by malondialdehyde (MDA) content with spectrophotometric methods. The natural plant extracts not only diminish the Vc/Fe²⁺,Cys/Fe²⁺ induced microsomal lipid peroxidation, UV light induced erythrocyte membrane lipid peroxidation and also showed its activity in a concentration-dependent manner. Our study found that the higher tannins contents showed more effective of antioxidant properties. Keywords: Punica granatum L.; liver microsome; antioxidant activity; Lipid peroxidation

Abstract: As one of Best Management Practices, Vegetative Filter Strip (VFS) had been widely application and their effects were fine. Planning and design VFS is based on quantitative predicting the purification effect. A mathematical model by coupling Vegetative Filter Strip Model (VFSMOD) with the Modified Universal Soil Loss Equation (MUSLE) was designed to estimate sediments trapping efficiency of VFS under the different conditions. Furthermore, in this paper the applicability of coupling model had been tested well by plot experiments in Chinese northwest, so the coupling model was applied to simulate the efficacy of VFS in Shaanxi Heihe River basin. Result reveals that grassed filter strips with about 10 m width are reasonable in Heihe River basin. Besides that, it is unsuitable to set grassed filter strips under the conditions of 15° above slope in river bank.