五味子醇甲对APP/PS1小鼠学习记忆和NF-κB p65的影响

目的研究五味子醇甲(SCH)对APP/PS1双转基因痴呆小鼠行为学和NF-κB p65的影响。方法将35只APP/PS1双转基因痴呆小鼠随机分为模型(APP/PS1)组、五味子醇甲(SCH+APP/PS1)组;另以同背景同月龄的C 57 BL/6 J阴性小鼠为空白(WT)组。SCH+APP/PS1组给予SCH悬浊液灌胃(2.6 mg·kg^-1·d^-1),模型组和空白组给予等量蒸馏水灌胃。各组灌胃30 d进行Mirror水迷宫空间探索试验后取材。HE染色法观察皮层及海马CA1区神经细胞的形态结构。运用DCFH-DA法检测脑组织活性氧(ROS)含量。Western印迹检测法检验磷酸化核转录因子(NF-κB p65,pp65)的表达。结果与APP/PS 1组相比,APP/PS 1+SCH组有效区停留距离及时间明显延长,差异有统计学意义(P<0.05,P<0.01);APP/PS 1+SCH组穿越有效区次数和平台区停留距离增加,均差异有统计学意义(P<0.01)。APP/PS 1+SCH组HE染色观察皮层有部分神经细胞萎缩、减少,较APP/PS1组明显好转,海马细胞排列整齐度尚可、较均匀。与APP/PS1组相比,APP/PS1+SCH组能降低ROS含量,差异有统计学意义(P<0.05)。APP/PS 1+SCH组皮层及海马pp65蛋白相对表达量下调(P<0.05,P<0.01)。结论SCH可能通过降低ROS含量和抑制pp65保护脑组织形态结构和提高APP/PS1鼠空间探索记忆能力。     

甘草素在体外不同种属肝微粒体中的代谢差异研究

目的对甘草苷的苷元甘草素在体外不同种属肝微粒体中的代谢差异进行比较研究,为甘草苷的进一步研究开发提供参考依据。方法甘草素与不同种属,包括大鼠、小鼠、人、犬及猴的肝微粒体进行孵育,比较其代谢稳定性和代谢转化情况。代谢稳定性通过底物消除法分析甘草素的剩余底物浓度水平随时间的变化,计算体外消除半衰期(t1/2)。进一步对甘草素在肝微粒体孵育后生成的代谢产物谱以及代谢途径进行分析。结果在I相肝微粒体孵育体系中,甘草素在5个种属肝微粒体中发生代谢的t1/2依次为大鼠小鼠人猴犬;在II相肝微粒体孵育体系中,甘草素代谢都非常快,除小鼠外,均在5 min内下降50%以上。甘草素与人肝微粒体进行II相孵育产生的代谢产物谱和猴的相同,其余种属则与人有明显不同。结论甘草素在猴肝微粒体中的代谢稳定性和代谢产物谱均与人最相似,其次为犬肝微粒体,大鼠和小鼠则与人存在明显差异。在进一步的临床前药代和毒理研究中可选用猴或犬作为模型动物。     

双氢青蒿素通过调节凋亡相关蛋白的表达及活性氧的产生而抑制胰腺癌JF-305细胞的增殖

探讨双氢青蒿素诱导人胰腺癌JF-305细胞凋亡作用及活性氧在双氢青蒿素诱导JF-305细胞凋亡中的作用。采用MTT法考察不同浓度双氢青蒿素对人胰腺癌JF-305细胞增殖的影响,流式细胞术检测细胞周期,Hochest 333258荧光染色法观察细胞凋亡形态,Annexin V荧光染色法检测JF-305细胞凋亡的变化,DCFH-DA检测凋亡过程中活性氧(ROS)的变化。Western blot检测细胞内Bax,Bcl-2,Cleaved caspase-3,Cleaved caspase-9和Cyto C蛋白表达的变化。与对照相比,双氢青蒿素作用JF-305细胞48 h,细胞增殖受到明显抑制(P0.05);细胞被阻滞于G2/M期;细胞出现核浓缩聚集、碎裂的凋亡形态,细胞凋亡比例升高(P0.05);DCFH-DA检测双氢青蒿素给药组细胞ROS明显升高(P0.05);Western blot结果显示,双氢青蒿素作用后细胞内Bcl-2蛋白表达下调,Bax蛋白表达上调,Bax/Bcl-2蛋白表达比例升高,Cleaved caspase-3,Cleaved caspase-9和Cyto C蛋白表达升高。双氢青蒿素能诱导JF-305细胞凋亡,其凋亡过程可能与ROS的生成增加相关。     

澜沧县受威胁药用维管束植物的多样性及其分布特征

丰富的药用植物多样性是我国中医药事业发展的重要物质基础,摸清地区资源现状,可以为其药用资源的可持续保护和开发利用提供科学指导。该文依据《全国中药资源普查技术规范》和《县域植物物种多样性调查与评估技术指导手册》对云南省澜沧拉祜族自治县(简称"澜沧县")开展了全县范围的中药资源普查及野生植物多样性调查与评估工作,分析了其中受威胁药用植物维管束植物的多样性及其分布特征,结果发现:全县境内共有受威胁药用维管束植物33种,隶属于17科23属,分别包括极危、濒危、易危等级的物种1种、10种、22种。这些受威胁药用维管束植物分布在澜沧县境内的不同区域,以县东南部的糯扎渡镇和发展河乡、西南部的糯福乡以及西部的竹塘乡包含的受威胁物种多样性最为丰富,且其物种丰富度随海拔的变化呈单峰格局。研究仅发现6种受威胁药用维管束植物在糯扎渡自然保护区澜沧片区内受到保护,而多数该类群物种丰富的区域尚未得到有效保护。因此,该文建议进一步完善现有保护体系,以更好地保护和利用澜沧县地区的药用植物多样性。     

燕窝DNA条形码的鉴定研究

应用Cytb序列对燕窝进行DNA条形码(DNA barcodes)研究,为燕窝的溯源研究及全面评价燕窝质量提供理论依据。以马来西亚、印度尼西亚、越南、泰国等地的燕窝,共计39个样本为研究对象,提取基因组DNA,扩增Cytb序列并双向测序。采用MEGA 7.0软件,对39条样本序列及36条从Gen Bank中下载5种金丝燕的Cytb序列进行序列特征分析,基于Kimura双参数法计算序列种内、种间遗传距离,构建NJ和UPGMA系统聚类树进行分析。研究结果表明,39个样本共来源于3个不同的金丝燕物种。Cytb序列种间变异显著大于其种内变异,可以准确地区分不同种类的燕窝。所构建的NJ和UPGMA系统发育树,也能将全部物种区分开。表明基于Cytb序列的DNA条形码技术可用于准确快速地鉴别燕窝的生物基原。     

Prunus armeniaca L (apricot) protects rat testes from detrimental effects of low-dose x-rays

Exposure to low x-ray doses damages the spermatozoa, mainly by late-onset (ie, after 3 months) oxidative stress. Antioxidants ameliorate oxidation and prevent tissue damage. Prunus armeniaca L (apricot), rich in carotenoids and vitamins, is a potent natural antioxidant. We hypothesized that an apricot-rich diet might ameliorate the detrimental effects of low-dose x-rays on testis tissue. A 20% apricot diet was composed isoenergetically to the regular rodent diet. The total phenolic content, reducing power, and antioxidant capacity of both diets were determined. Sprague-Dawley rats received apricot-rich diets before and after x-ray exposure. Regular diets were given to controls. Rats were exposed to 0.2 Gy x-rays at the eighth week and were euthanized at the 20th postexposure week. Testicular oxidative status was determined by tissue thiobarbituric acid-reactive substances, reduced glutathione, superoxide dismutase, and catalase activities. For histologic evaluation, qualitative and quantitative microscopic determinations were performed, and Leydig and Sertoli cell counts and Johnsen scores were measured. The control diet group had significant testicular oxidative stress and mild tissue deterioration. Leydig and Sertoli cell counts, tubule diameters, and Johnsen scores were significantly decreased in the exposure groups. Apricot-rich diet significantly ameliorated the oxidative status and prevented the damage in tubular histology. The protective effects were prominent when the diet was maintained throughout the time course and were partially protected when the diet was initiated after exposure. The natural antioxidant activity of apricot ameliorates the delayed detrimental effects of low-dose irradiation on testis tissue. The high total antioxidant capacity of the apricot deserves further investigation.     

Relative deprivation and child health in the USA

Some recent papers have suggested that relative deprivation could be negatively related to health through psychosocial stress and related behaviors. While there is a large literature on the association between absolute deprivation, i.e., income, and child health, little is known about the association between relative deprivation and child health. This paper asks: controlling for a measure of absolute deprivation, is a mother’s relative deprivation related to infant health and maternal health behavior? There are many limitations regarding our measures and methods, and we interpret our results only as associations. Using US 2001 Natality Detail data, we find that pregnant women of lower socioeconomic status relative to other expectant mothers in their Metropolitan Statistical Area give birth to very slightly lighter babies and are more likely to smoke. A back-of-the envelope calculation shows the magnitude of the association we observe between relative deprivation and birthweight is close to what medical studies would predict if the probability of prenatal tobacco use were to increase by the amount we estimate.     

Resveratrol inhibits angiotensin II-induced ERK1/2 activation by downregulating quinone reductase 2 in rat vascular smooth muscle cells

Our previous studies showed that resveratrol could inhibit the proliferation of vascular smooth muscle cells (VSMCs) and repress mRNA and protein expression of quinone reductase 2 (NQO2).This study further explored the potential mechanisms whereby resveratrol inhibits the proliferation of rat VSMCs.Lentiviral vectors that incorporated NQO2 small interfering RNA (siRNA) were constructed and transduced into rat VSMCs.The cell proliferation was detected using the bromodeoxyuridine (BrdU) assay.Cultured rat VSMCs were stimulated with angiotensin II and the level of reactive oxygen species (ROS) was measured using a ROS assay kit.A realtime quantitative PCR was used to detect NQO2 mRNA levels.Extracellular signal-regulated kinase (ERK1/2) and NQO2 protein expression were determined by Western blotting analysis.The inhibitory effect of resveratrol (10 and 50 μmol/L) on the proliferation of rat VSMCs in the NQO2 siRNA group was significantly weaker than that in the normal and scrambled siRNA group (P < 0.01).The ROS level in the NQO2 siRNA and resveratrol (50 μmol/L) treatment groups were lower than that in the normal and scrambled siRNA groups (P < 0.01 in both).Compared with the normal and scrambled siRNA group,the phosphorylation of ERK1/2 was significantly decreased in the NQO2 siRNA and resveratrol (50 μmol/L) treatment group (P < 0.01 in both).In conclusion,high concentration of resveratrol inhibits angiotensin II-induced ERK1/2 phosphorylation and subsequent proliferation by down-regulation of NQO2 in cultured rat VSMCs.     

Involvement of Rho kinase (ROCK) in sepsis-induced acute lung injury

Indirect acute lung injury is associated with high morbidity and mortality. We investigated the link between Rho kinase (ROCK) activation and apoptotic cell death in sepsis induced acute lung injury. This hypothesis was tested by administering a specific, selective inhibitor of ROCK (Y-27632) to rats subjected to cecal ligation and puncture (CLP). Rats were randomly divided into 4 groups as; sham-operated, sham + Y-27632, CLP and CLP + Y-27632. Twenty-four hours later, each experiment was terminated and lungs analyzed. Histopathology was assessed by hematoxylin-eosin staining and the presence of apoptosis was evaluated through the TUNEL assay. Pulmonary activity of caspase 3 and ROCK 1 & 2 were measured by western blot. Interstitial edema, severely damaged pulmonary architecture with massive infiltration of the inflammatory cells and an increase in lung tissue TBARS levels as well as 3-NT to total tyrosine ratios were observed in untreated CLP animals. Pretreatment of animals with Y-27632, reduced lung injury in the CLP induced septic rats in each of these parameters of lung injury (p<0.05). Western immunoblot revealed active caspase cleavage and increased expression of active fragment of ROCK 1 & 2 in the CLP group. TUNEL assay showed an increase in percentage of apoptotic cells when comparing the CLP group with the CLP + Y-27632 group. These results suggest an important role of Rho kinase in sepsis induced lung injury by a mechanism that might be related to oxidative and/or nitrosative stress mediated caspase cleavage leading to apoptosis.