Regulation of Opioid Receptors by Their Endogenous Opioid Peptides

Cellular and Molecular Neurobiology - Activation of μ, δ, and κ opioid receptors by endogenous opioid peptides leads to the regulation of many emotional and physiological responses....     

Reduction of In-Stent Restenosis Risk on Nickel-Free Stainless Steel by Regulating Cell Apoptosis and Cell Cycle

High nitrogen nickel-free austenitic stainless steel (HNNF SS) is one of the biomaterials developed recently for circumventing the in-stent restenosis (ISR) in coronary stent applications. To understand the ISR-resistance mechanism, we have conducted a comparative study of cellular and molecular responses of human umbilical vein endothelial cells (HUVECs) to HNNF SS and 316L SS (nickel-containing austenitic 316L stainless steel) which is the stent material used currently. CCK-8 analysis and flow cytometric analysis were used to assess the cellular responses (proliferation, apoptosis, and cell cycle), and quantitative real-time PCR (qRT-PCR) was used to analyze the gene expression profile of HUVECs exposed to HNNF SS and 316L SS, respectively. Flow cytometry analysis revealed that 316L SS could activate the cellular apoptosis more efficiently and initiate an earlier entry into the S-phase of cell cycle than HNNF SS. At the molecular level, qRT-PCR results showed that the genes regulating cell apoptosis and autophagy were overexpressed on 316L SS. Further examination indicated that nickel released from 316L SS triggered the cell apoptosis via Fas-Caspase8-Caspase3 exogenous pathway. These molecular mechanisms of HUVECs present a good model for elucidating the observed cellular responses. The findings in this study furnish valuable information for understanding the mechanism of ISR-resistance on the cellular and molecular basis as well as for developing new biomedical materials for stent applications.     

Antioxidant action of acteoside and its analogs on lipid peroxidation

Summary

We have investigated antioxidant actions of acteoside (ACT) and another natural phenylpropanoid glycoside, cistanoside F (CIS-F) on lipid peroxidation in rat liver mitochondria (RLM) and rat liver mitochondrial lipid (RLML) liposomes induced by Fe²⁺/ADP. A synthetic ACT analogue, TX-1847, was also examined. Oxygen consumption, the formation of thiobarbituric acid reactive substances (TBARs) and glutathione concentration were determined simultaneously during lipid peroxidation. The radical scavenging activity of the compounds was evaluated by using 1,1-diphenyl-2-picrylhydrazyl. ACT and its analogs produced dose-dependent inhibitions of mitochondrial and liposomal lipid peroxidation (ACT ≈ CIS-F > TX-1847). Their radical scavenging activities were ranked as follows: TX-1847 > ACT > CIS-F. ACT, CIS-F, and TX-1847 spared reduced glutathione (GSH) during mitochondrial lipid peroxidation. The radical scavenging activities of the compounds did not parallel their anti-peroxidative activities. The data are consistent with the idea that the inhibitory activities of phenylpropanoids were primarily due to a radical chain-breaking mechanism. The sugar moieties in ACT and CIS-F, and/or the conformational structure of the compounds, also seem to play an important role in their inhibitory effects on lipid peroxidation.     

Prolonging the female reproductive lifespan and improving egg quality with dietary omega‐3 fatty acids

Women approaching advanced maternal age have extremely poor outcomes with both natural and assisted fertility. Moreover, the incidence of chromosomal abnormalities and birth defects increases with age. As of yet, there is no effective and practical strategy for delaying ovarian aging or improving oocyte quality. We demonstrate that the lifelong consumption of a diet rich in omega‐3 fatty acids prolongs murine reproductive function into advanced maternal age, while a diet rich in omega‐6 fatty acids is associated with very poor reproductive success at advanced maternal age. Furthermore, even short‐term dietary treatment with a diet rich in omega‐3 fatty acids initiated at the time of the normal age‐related rapid decline in murine reproductive function is associated with improved oocyte quality, while short‐term dietary treatment with omega‐6 fatty acids results in very poor oocyte quality. Thus, omega‐3 fatty acids may provide an effective and practical avenue for delaying ovarian aging and improving oocyte quality at advanced maternal age.     

The Association between Four Genetic Variants in MicroRNAs (rs11614913, rs2910164, rs3746444, rs2292832) and Cancer Risk: Evidence from Published Studies

MicroRNAs (miRNAs) participate in diverse biological pathways and may act as either tumor suppressor genes or oncogenes. Single nucleotide polymorphisms (SNPs) in miRNA may contribute to cancer development with changes in the microRNA''s properties and/or maturation. Polymorphisms in miRNAs have been suggested in predisposition to cancer risk; however, accumulated studies have shown inconsistent conslusionss. To further validate determine whether there is any potential association between the four common SNPs (miR-196a2C>T, rs11614913; miR-146aG>C, rs2910164; miR-499A>G, rs3746444; miR-149C>T, rs2292832) and the risk for developing risk, a meta-analysis was performed according to the 40 published case-control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the extent of the association. The results demonstrated that the rs11614913TT genotype was significantly associated with a decreased cancer risk, in particular with a decreased risk for colorectal cancer and lung cancer, or for Asian population subgroup. In addition, the rs2910164C allele was associated with decreased risk for esophageal cancer, cervical cancer, prostate cancer, and hepatocellular carcinoma (HCC), in particular in Asian population subgroup. Similarly, the rs3746444G allele was observed as a risk factor for cancers in the Asian population. It is concluded that two SNPs prsent in miRNAs(rs11614913TT, and rs2910164C) may protect against the pathogenesis of some cancers, and that the rs3746444 may increase risk for cancer.     

Low SIRT3 Expression Correlates with Poor Differentiation and Unfavorable Prognosis in Primary Hepatocellular Carcinoma

SIRT3, a mitochondrial sirtuin belonging to nicotinamide adenine nucleotide (NAD) dependent deacetylases, is implicated in metabolism, longevity and carcinogenesis. SIRT3 expression and its significance in hepatocellular carcinoma (HCC) remain largely unclear. In this study, we demonstrated that SIRT3 expression in HCC tissue was much lower than that in paracarcinoma tissue, at both mRNA and protein levels. The cutoff value for low SIRT3 expression in HCC was defined according to receiver operating characteristic curve (ROC) analysis. As disclosed by immunohistochemistry (IHC) results, low SIRT3 expression was present in 67.3% (167/248) of HCC cases. Furthermore, low expression of SIRT3 was significantly correlated to differentiation (P = 0.013), clinical stage (P = 0.005), serum AFP level (P<0.01), tumor multiplicity (P = 0.026) and relapse (P = 0.028). Moreover, Kaplan-Meier analysis indicated that low SIRT3 expression associated with unfavorable overall survival (P<0.01) and recurrence-free survival (P = 0.004). The prognostic impact of SIRT3 was further confirmed by stratified survival analysis. Importantly, multivariate analysis revealed that low SIRT3 expression was an independent poor prognostic marker for overall survival (Hazard Ratio (HR) 0.555, 95% confidence interval (95% CI) 0.344–0.897, P = 0.016). Collectively, we conclude that SIRT3 is decreased in HCC and is a novel unfavorable marker for prognosis of patients with this fatal disease.     

A Report on the Chromosome Numbers of Chinese Umbelliferae

Chromosome numbers are reported for 26 species and varieties of Umbelliferae which belong to 3 subfamilies and 19 genera in this paper. Of these, 13 counts are new records and some problems about chromosome numbers of Umbelliferae are simplydiscussed.     

Probiotic Properties and Cellular Antioxidant Activity of <Emphasis Type="Italic">Lactobacillus plantarum</Emphasis> MA2 Isolated from Tibetan Kefir Grains

Lactobacillus plantarum MA2 was isolated from traditional Chinese Tibetan kefir grains. Its antioxidant properties had been demonstrated in vitro and in vivo previously. In the present study, the probiotic characteristics of this strain were further evaluated by investigating its acid and bile salt tolerances, cell surface hydrophobicity, and autoaggregation, respectively. In addition, the cellular antioxidant activity (CAA) assay was applied to test the antioxidant capacity of the isolate in different growth phases. Same method was also used to evaluate the antioxidant capacity of its fermentation supernatant, cell-free extract, and intact cell quantitatively. The results of probiotic characteristic tests showed that MA2 could survive at pH 2.5 and 0.3% bile salt. Meanwhile, the measurements of cell surface hydrophobicity and autoaggregation were 45.29?±?2.15 and 6.30?±?0.34%, respectively. The results of cellular antioxidant activity tests indicated that MA2 had high antioxidant potential. The CAA value of logarithmic phase cell-free extract of MA2 (39,450.00?±?424.05 μmol quercetin equivalents/100 g sample) was significantly higher than that in stationary phase cell-free extract (3395.98?±?126.06 μmol quercetin equivalents/100 g sample) and that of fermentation supernatant in logarithmic phase (2174.41?±?224.47 μmol quercetin equivalents/100 g sample) (p?<?0.05). The CAA method was successively applied to evaluate the antioxidant capacity of MA2 in this study, which suggests that it could be used as a useful method for lactic acid bacteria antioxidant potential evaluation.     

黄土高原部分地区180－73万年间孢粉植物群和环境演变初探

根据黄土高原３个剖面的孢粉资料及测年数据,恢复了本区１８０－７３万年期间的植被面貌。在此基础上,结合中国和全球其它地区的孢粉、构造、地层、水系演化和火山活动等特征。将此期间植被、气候和环境的演化划分为３个主旋回,６个主要演化阶段,１０个亚阶段和５个事件。初步认识到,该时间段的气候环境演化有较大波动,且这些变化不限于局部地区,而是区域性的,是多种因素（内外动力）作用的结果,且有规律可循。