Gypenosides alleviate myocardial ischemia-reperfusion injury via attenuation of oxidative stress and preservation of mitochondrial function in rat heart

Gypenosides (GP) are the predominant components of Gynostemma pentaphyllum, a Chinese herb medicine that has been widely used for the treatment of chronic inflammation, hyperlipidemia, and cardiovascular disease. GP has been demonstrated to exert protective effects on the liver and brain against ischemia-reperfusion (I/R) injury, yet whether it is beneficial to the heart during myocardial I/R is unclear. In this study, we demonstrate that pre-treatment with GP dose-dependently limits infarct size, alleviates I/R-induced pathological changes in the myocardium, and preserves left ventricular function in a rat model of cardiac I/R injury. In addition, GP pre-treatment reduces oxidative stress and protects the intracellular antioxidant machinery in the myocardium. Further, we show that the cardioprotective effect of GP is associated with the preservation of mitochondrial function in the cardiomyocytes, as indicated by ATP level, enzymatic activities of complex I, II, and IV on the mitochondrial respiration chain, and the activity of citrate synthase in the citric acid cycle for energy generation. Moreover, GP maintains mitochondrial membrane integrity and inhibits the release of cytochrome c from the mitochondria to the cytosol. The cytoprotective effect of GP is further confirmed in vitro in H9c2 cardiomyoblast cell line with oxygen-glucose deprivation and reperfusion (OGD/R), and the results indicate that GP protects cell viability, reduces oxidative stress, and preserves mitochondrial function. In conclusion, our study suggests that GP may be of clinical value in cytoprotection during acute myocardial infarction and reperfusion.     

Whole-genome sequencing to detect mutations associated with resistance to insecticides and Bt proteins in Spodoptera frugiperda

The fall armyworm (FAW), Spodoptera frugiperda, is a major pest native to the Americas that has recently invaded the Old World. Point mutations in the target-site proteins acetylcholinesterase-1 (ace-1), voltage-gated sodium channel (VGSC) and ryanodine receptor (RyR) have been identified in S. frugiperda as major resistance mechanisms to organophosphate, pyrethroid and diamide insecticides respectively. Mutations in the adenosine triphosphate-binding cassette transporter C2 gene (ABCC2) have also been identified to confer resistance to Cry1F protein. In this study, we applied a whole-genome sequencing (WGS) approach to identify point mutations in the target-site genes in 150 FAW individuals collected from China, Malawi, Uganda and Brazil. This approach revealed three amino acid substitutions (A201S, G227A and F290V) of S. frugiperda ace-1, which are known to be associated with organophosphate resistance. The Brazilian population had all three ace-1 point mutations and the 227A allele (mean frequency = 0.54) was the most common. Populations from China, Malawi and Uganda harbored two of the three ace-1 point mutations (A201S and F290V) with the 290V allele (0.47–0.58) as the dominant allele. Point mutations in VGSC (T929I, L932F and L1014F) and RyR (I4790M and G4946E) were not detected in any of the 150 individuals. A novel 12-bp insertion mutation in exon 15 of the ABCC2 gene was identified in some of the Brazilian individuals but absent in the invasive populations. Our results not only demonstrate robustness of the WGS-based genomic approach for detection of resistance mutations, but also provide insights for improvement of resistance management tactics in S. frugiperda.     

温度和盐分胁迫对新疆鼠尾草种子萌发的影响

利用控制实验研究了温度和盐分胁迫对新疆鼠尾草种子萌发的影响.结果显示:新疆鼠尾草种子萌发的最适温度为25℃.盐胁迫对新疆鼠尾草种子的萌发均有明显的抑制作用,随着盐浓度的增加,萌发率和萌发速率下降.在适宜萌发温度下,新疆鼠尾草耐盐极限值0.2 mmol/L.     

L7811鼠腹水肿瘤细胞^31P核磁共振的研究

用~(31)P核磁共振技术(~(31)P-NMR)研究了L_(7811)鼠腹水肿瘤细胞和615系鼠胸腺细胞(正常对照细胞)。结果发现在肿瘤晚期阶段,L_(7811)腹水肿瘤细胞的含磷化合物未进入完全不活跃状态。此外,腹水肿瘤细胞的磷脂组成与含量亦有明显改变。因此,~(31)P-NMR谱可做为观察肿瘤细胞内能量生成和某些磷脂合成宏观动态过程的一项参考指标。     

韩国赫坎按蚊复合体3成员种核糖体DNA内转录间隔2区的比较(英文)

本文对韩国中华按蚊、雷氏按蚊和八代按蚊核糖体DNA (rDNA)内转录间隔 2区 (ITS2 )序列进行了比较研究。用PCR扩增的rDNA ITS2片段直接测序 ,每种蚊测定 3个个体 ,结果显示 :韩国中华按蚊、雷氏按蚊和八代按蚊的rDNA ITS2序列长度分别为 4 6 8bp、 4 51bp和 4 53bp ,GC含量分别为 4 4 .87%、 4 6 .2 %和 4 5.7% ,3种按蚊序列差异范围为 12 .16 %— 30 .74 %。研究表明 ,rDNA ITS2序列差异可用于韩国中华按蚊、雷氏按蚊和八代按蚊的分子鉴别。     

幽门螺杆菌HspA融合蛋白口服疫苗的构建

构建表达幽门螺杆菌的保护性抗原分热休克蛋白A亚单位(HspA）和霍乱毒素B亚单位（CtxB）的重组融合蛋白的生物工程菌株,以此制备幽门螺杆菌的口服疫苗。用PCR方法扩增hspA和ctxB两个目的的基因片段,将它们分别克隆至pSK（＋）质粒上,然后插入含T7启动子ET－22b（＋）的表达载体中,构建嗓基因的表达质量pET－hct,转化E.coliBL21(DE3）,经IPTG诱导表达融合蛋白HCT。经测序,hspA-ctxB(hct)融合基因片段由726bp组成,可以编码242个氨基酸残基的多肽。经SDS－PAGE和免疫印迹分析检测发现,融合基因表达的蛋白质相对分子质量约为30kD。融合蛋白经镍离子柱纯化、复性后,和HspA共同标记同位素^125I,然后给小鼠灌胃,结果观察到HCT组小鼠血清中的^125I的放射量要明显高于HspA组（P＜0．001）,且吸收峰值时间明显提前。融合蛋白中的CtxB可明显促进小鼠对HspA的吸收,HCT融合蛋白可以作为预防和治疗幽门螺杆菌感染的侯选口服疫苗。     

The Mitochondrial Genome of Raphanus sativus and Gene Evolution of Cruciferous Mitochondrial Types

To explore the mitochondrial genes of the Cruciferae family, the mitochondrial genome of Raphanus sativus (sat) was sequenced and annotated. The circular mitochondrial genome of sat is 239,723 bp and includes 33 protein-coding genes, three rRNA genes and 17 tRNA genes. The mitochondrial genome also contains a pair of large repeat sequences 5.9 kb in length, which may mediate genome reorga-nization into two sub-genomic circles, with predicted sizes of 124.8 kb and 115.0 kb, respectively. Furthermore, gene evolution of mitochondrial genomes within the Cruciferae family was analyzed using sat mitochondrial type (mitotype), together with six other re-ported mitotypes. The cruciferous mitochondrial genomes have maintained almost the same set of functional genes. Compared with Cycas taitungensis (a representative gymnosperm), the mitochondrial genomes of the Cruciferae have lost nine protein-coding genes and seven mitochondrial-like tRNA genes, but acquired six chloroplast-like tRNAs. Among the Cruciferae, to maintain the same set of genes that are necessary for mitochondrial function, the exons of the genes have changed at the lowest rates, as indicated by the numbers of single nucleotide polymorphisms. The open reading frames (ORFs) of unknown function in the cruciferous genomes are not conserved. Evolutionary events, such as mutations, genome reorganizations and sequence insertions or deletions (indels), have resulted in the non- conserved ORFs in the cruciferous mitochondrial genomes, which is becoming significantly different among mitotypes. This work represents the first phylogenic explanation of the evolution of genes of known function in the Cruciferae family. It revealed significant variation in ORFs and the causes of such variation.     

用鱼血清转氨酶监测水污染的研究

以三硝基甲苯(INT)、六六六、滴滴涕(DDT)、对硫磷(E-605)、氯化汞分别进行白鲢鱼种的急性致毒实验,与对照组相比,鱼血清谷草转氨酶活性显著增加;对硫磷还引起血清谷丙转氨酶活性的升高。血清转氨酶活性增加的程度与氯化汞浓度相关。不同种类的我国淡水鲤科鱼类、不同鱼龄、不同水体以及短期饥饿、惊扰及网箱饲养对血清转氨酶活性没有影响,但水温升高或溶氧低于1ppm会使鱼血清谷草转氨酶活性升高。水温与鱼血清谷草转氨酶活性有相关性。       

A study on the protective effects of CpG oligodeoxynucleotide-induced mucosal immunity against lung injury in a mouse acute respiratory distress syndrome model

This study aims to determine the feasibility of using oligodeoxynucleotides with unmethylated cytosine-guanine dinucleotide sequences (CpG ODN) as an immunity protection strategy for a mouse model of acute respiratory distress syndrome (ARDS). This is a prospective laboratory animal investigation. Twenty-week-old BALB/c mice in Animal research laboratory were randomized into groups. An ARDS model was induced in mice using lipopolysaccharides (LPSs). CpG ODN was intranasally and transrectally immunized before or after the 3rd and 7th days of establishing the ARDS model. Mice were euthanized on Day 7 after the second immunization. Then, retroorbital bleeding was carried out and the chest was rapidly opened to collect the trachea and tissues from both lungs for testing. CpG ODN significantly improved the pathologic impairment in mice lung, especially after the intranasal administration of 50 μg. This resulted in the least severe lung tissue injury. Furthermore, interleukin-6 (IL-6) and IL-8 concentrations were lower, which was second to mice treated with the rectal administration of 20 µg CpG ODN. In contrast, the nasal and rectal administration of CpG ODN in BALB/c mice before LPS immunization did not appear to exhibit any significant protective effects. The intranasal administration of CpG ODN may be a potential treatment approach to ARDS. More studies are needed to further determine the protective mechanism of CpG ODN.     

The effect of receptor protein tyrosine phosphatase kappa on the change of cell adhesion and proliferation induced by N‐acetylglucosaminyltransferase V

N‐acetylglucosaminyltransferase V (GnT‐V) has been reported to be positively associated with tumor progression, but its mechanism still remains unknown. In the present study, we found that GnT‐V overexpression not only changed the glycosylation of receptor protein tyrosine phosphatase kappa (RPTPκ) but also decreased its protein level. Moreover, GnT‐V overexpression decreased cell calcium‐independent adhesion and increased the tyrosine phosphorylation level of β‐catenin, in which RPTPκ played an important role. Since RPTPκ has an RXKR motif, which is a favored cleavage site for furin, we used furin inhibitor to further explore the effect of RPTPκ on the change of cell adhesion and β‐catenin signaling induced by GnT‐V. Our results showed that preventing RPTPκ cleavage rescued the above effects of GnT‐V, suggesting that furin cleavage could be one of the factors for RPTPκ to regulate cell adhesion and β‐catenin signaling in GnT‐V overexpression cell lines. In addition, the increased tyrosine phosphorylation level of β‐catenin was associated with the increased nuclear level of β‐catenin and downstream signaling molecules such as c‐myc and cyclin D1 that were associated with cell proliferation. Our results suggest that GnT‐V could decrease human hepatoma SMMC‐7721 cell adhesion and promote cell proliferation partially through RPTPκ. J. Cell. Biochem. 109: 113–123, 2010. © 2009 Wiley‐Liss, Inc.