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81.
Hao Jia Wei Chen Xiaoping Yu Xiuhua Wu Shuai Li Hong Liu Jiru Liao Weihua Liu Mantian Mi Longjian Liu Daomei Cheng 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):345-353
The effects of black rice anthocyanidins (BRACs) on retinal damage induced by photochemical stress are not well known. In the present study, Sprague-Dawley rats were fed AIN-93M for 1 week, after which 80 rats were randomly divided into two groups and treated with (n = 40) or without BRACs (n = 40) for 15 days, respectively. After treatment, both groups were exposed to fluorescent light (3,000 ± 200 lux; 25℃), and the protective effect of dietary BRACs were evaluated afterwards. Our results showed that dietary BRACs effectively prevented retinal photochemical damage and inhibited the retinal cells apoptosis induced by fluorescent light (p < 0.05). Moreover, dietary BRACs inhibited expression of AP-1 (c-fos/c-jun subunits), up-regulated NF-κB (p65) expression and phosphorylation of IκB-α, and decreased Caspase-1 expression (p < 0.05). These results suggest that BRACs improve retinal damage produced by photochemical stress in rats via AP-1/NF-κB/Caspase-1 apoptotic mechanisms. 相似文献
82.
83.
Giovanna Romano Emiliano Manzo Gian Luigi Russo Giuliana d’Ippolito Adele Cutignano Maria Russo Angelo Fontana 《Marine drugs》2013,11(11):4527-4543
Oxylipins are a large and diverse family of fatty acid derivatives exhibiting different levels of oxidation of the carbon chain. They are involved in many biological functions in mammals, plants and diatoms. In this last group of organisms, they are suggested to play a role in the reproductive failure of copepod predators, showing clear pro-apoptotic effects on newborn nauplii. In this work, these compounds were tested for the ability to induce mitotic arrest in sea urchin embryos. We show for the first time that oxylipins have an increased efficacy in their corresponding methylated form. Natural oxylipins were also used as an inspiration for the rational design and synthesis of stable chemical analogs with apoptotic activity against tumor cell lines. This approach led to the synthesis of the linear C15-ketol (22) that was shown to induce apoptosis in human leukemia U-937 cells. These results are proof of the concept of the use of eco-physiological considerations as a platform to guide the search for novel drug candidates. 相似文献
84.
Babak Esmaeelian Kirsten Benkendorff Martin R. Johnston Catherine A. Abbott 《Marine drugs》2013,11(10):3802-3822
Dicathais orbita is a large Australian marine gastropod known to produce bioactive compounds with anticancer properties. In this research, we used bioassay guided fractionation from the egg mass extract of D. orbita using flash column chromatography and identified fractions containing tyrindoleninone and 6-bromoisatin as the most active against colon cancer cells HT29 and Caco-2. Liquid chromatography coupled with mass spectrometry (LCMS) and 1H NMR were used to characterize the purity and chemical composition of the isolated compounds. An MTT assay was used to determine effects on cell viability. Necrosis and apoptosis induction using caspase/LDH assay and flow cytometry (PI/Annexin-V) and cell cycle analysis were also investigated. Our results show that semi-purified 6-bromoisatin had the highest anti-cancer activity by inhibiting cell viability (IC50 = ~100 µM) and increasing caspase 3/7 activity in both of the cell lines at low concentration. The fraction containing 6-bromoisatin induced 77.6% apoptosis and arrested 25.7% of the cells in G2/M phase of cell cycle in HT29 cells. Tyrindoleninone was less potent but significantly decreased the viability of HT29 cells at IC50 = 390 µM and induced apoptosis at 195 µM by increasing caspase 3/7 activity in these cells. This research will facilitate the development of these molluscan natural products as novel complementary medicines for colorectal cancer. 相似文献
85.
中草药复方制剂对青脚麻鸡法氏囊免疫功能、抗氧化性及增殖凋亡基因表达的影响 总被引:1,自引:0,他引:1
试验旨在研究由金银花、黄连、蒲公英等药材组成的中草药复方制剂,对青脚麻鸡法氏囊组织结构、抗氧化功能、细胞因子和抗体分泌及增殖凋亡相关基因(PCNA和Caspase-3)表达的影响。采用单因子试验设计,将400羽青脚麻鸡按照体重相近原则分为对照组(基础日粮)和试验Ⅰ-Ⅲ组(分别添加0.5%、1.0%和1.5%中草药复方制剂),每组5个重复(n=20),试验期56 d。结果表明,28日龄时,添加1.0%中草药复方制剂可增加青脚麻鸡法氏囊细胞因子(IL-2和IFN-γ)、IBDV抗体和GSH-Px含量及PCNA mRNA和蛋白表达量(P0.05),降低Caspase-3 mRNA和蛋白表达量(P0.05)。56日龄时,添加1.0%中草药复方制剂可增加青脚麻鸡法氏囊IFN-γ、IBDV抗体和GSH-Px含量(P0.05),降低MDA含量及Caspase-3蛋白表达量(P0.05)。显微观察可见,28和56日龄时,添加1.0%中草药复方制剂可显著增加法氏囊小叶和淋巴小结面积(P0.05),降低法氏囊Caspas-3阳性细胞数量,说明日粮中添加1.0%中草药复方制剂对法氏囊组织结构及免疫抗氧化功能均有明显改善,对法氏囊增殖和凋亡相关基因表达有明显调控作用。文章分别从分子和组织水平揭示中草药复方制剂对青脚麻鸡法氏囊生长发育和免疫功能的影响及可能机制,为新型中草药复方制剂研发及其在青脚麻鸡生产中的应用提供科学依据。 相似文献
86.
目的 探讨三物白散对Survivin-RNA基因沉默转染胃癌SGC-7901细胞凋亡、迁移的影响。方法 将实验分成6组:空白对照组、LV-RNAi 组、Survivin-RNAi-LV组、空白对照+中药组、LV-RNAi+中药组、Survivin-RNAi-LV+中药组;采用流式细胞仪检测各组细胞的凋亡,划痕实验检测各组细胞的迁移能力。结果 细胞凋亡率:Survivin-RNAi-LV组明显高于空白对照组和LV-RNAi组(P<0.05);Survivin-RNAi-LV+中药组与空白对照+中药组、LV-RNAi+中药组比较明显较高(P<0.05);Survivin-RNAi-LV+中药组高于Survivin-RNAi-LV组,差异具有统计学意义(P<0.05)。胃癌细胞的24 h迁移率:Survivin-RNAi-LV组明显低于空白对照组和LV-RNAi组(P<0.05);Survivin-RNAi-LV+中药组与空白对照+中药组、LV-RNAi+中药组比较,其结果明显低于后两组(P<0.05);Survivin-RNAi -LV+中药组与Survivin-RNAi-LV组比较,细胞迁移率明显降低,差异有统计学意义(P<0.05)。结论 Survivin基因沉默转染,增强了三物白散诱导胃癌SGC-7901细胞凋亡和抑制其迁移的作用。 相似文献
87.
目的 探讨加味大柴胡汤在临床上辅助治疗老年阻塞性黄疸的理论机制。方法 通过结扎胆总管的外科手术方法建立阻塞性黄疸老年大鼠模型,实验分为假手术组、模型组、加味大柴胡汤组,予以相应干预,分3、7、10 d共3个时间段,每组10只SPF级老年SD大鼠,在各时间段取老年大鼠肝组织及心脏血,检测AST、ALT及TBA;采用钙离子试剂盒检测老年鼠肝组织匀浆钙离子浓度;采用Western Blot法检测老年鼠肝组织TRPC1蛋白的表达,采用Tunel法观察肝细胞凋亡情况。结果 造模成功后各时间点模型组、加味大柴胡汤组与假手术组比较,ALT、AST、TBA和Ca2+浓度均升高,且模型组上升更明显(P<0.01),模型组、加味大柴胡汤组的TRPC1的蛋白含量也均高于假手术组(P<0.01),且加味大柴胡汤组肝细胞的凋亡率低于模型组(P<0.01)。结论 梗阻性黄疸老年大鼠TRPC1表达明显升高,加味大柴胡汤下调TRPC1的表达,可能是其降低钙超载,减少肝细胞凋亡的机制之一。 相似文献
88.
目的 细胞凋亡作为昆虫免疫应答的重要组成部分,在病毒与宿主相互作用的过程中扮演着重要角色,以细胞凋亡相关基因为研究对象对阐明其在病毒感染过程中的作用具有重要的参考价值。本研究旨在筛选家蚕凋亡抑制蛋白(Bombyx mori inhibitor of apoptosis protein,BmIAP)的相互作用蛋白,并验证其在家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus, BmNPV)侵染过程中与Bmiap的相互调控关系及在BmNPV增殖过程中的作用,为探明宿主与BmNPV相互作用的分子机制提供理论依据。方法 利用免疫共沉淀技术筛选在BmNPV侵染家蚕细胞过程中与BmIAP相互作用的蛋白,对获得的特异性差异条带进行LC-MS/MS蛋白质谱分析,根据蛋白分子量大小并利用生物信息学方法对获得的蛋白进行鉴定,确定候选基因;通过分子克隆技术对候选基因进行克隆,利用SMART在线工具及BioEdit分别对候选基因的结构域进行预测及多序列比对分析;通过免疫荧光试验验证BmIAP和候选蛋白的细胞共定位情况,并进一步利用免疫共沉淀验证它们的相互作用;分别通过真核表达和基于CRISPR/Cas9的基因编辑系统对候选基因进行过表达和敲除,利用qRT-PCR技术检测相应基因的表达情况,以确定Bmiap和Bmpp5在BmNPV侵染过程中的调控关系;同样,在过表达和敲除Bmpp5后检测杆状病毒Vp39的表达量,以确定Bmpp5对BmNPV增殖的影响。结果 通过免疫共沉淀获得7个可能与BmIAP相互作用的宿主蛋白和1个BmNPV蛋白,进一步分析确定1个与凋亡相关的候选基因Bmpp5;Bmpp5的开放阅读框为1 473 bp,编码490个氨基酸,预测的蛋白分子量约为56 kD,含3个TRP结构域和1个PP2Ac结构域,在昆虫间具有较高的保守性;免疫荧光检测证明BmIAP和BmPP5共定位于细胞质中,免疫共沉淀结果表明两者可以相互作用;在BmNPV侵染过程中,过表达Bmiap后,Bmpp5的表达量显著上调,而敲除Bmiap后,Bmpp5的表达量显著下调,表明Bmiap能够促进Bmpp5的表达;同时,过表达Bmpp5后,Bmiap显著上调表达,而敲除Bmpp5后,Bmiap显著下调表达,表明Bmpp5同样能够促进Bmiap的表达;过表达Bmpp5能够促进BmNPV的增殖,敲除Bmpp5能够抑制BmNPV的增殖,表明Bmpp5的表达利于BmNPV的增殖。结论 鉴定了1个能够与BmIAP相互作用的蛋白BmPP5,且该蛋白在昆虫中高度保守;在BmNPV侵染过程中,Bmiap和Bmpp5能够相互促进,且Bmpp5能够促进BmNPV的复制增殖。 相似文献
89.
Jinglong LI Peng ZHANG Hongju LIU Wei REN Jinjing SONG Elizabeth RAO Eiki TAKAHASHI Ying ZHOU Weidong LI Xiaoping CHEN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1235-1240
Iron is involved in various physiological processes of the human body to maintain normal
functions. Abnormal iron accumulation in brain has been reported as a pathogenesis of
several neurodegenerative disorders and cognitive impairments. Hemojuvelin (HVJ) is a
membrane-bound and soluble protein in mammals that is responsible for the iron overload
condition known as juvenile hemochromatosis. Although iron accumulation in brain has been
related to neurodegenerative diseases, it remains unknown the effect of mutation of HVJ
gene on cognitive performance. In our studies, HJV(−/−) mice showed deficits in novel
object recognition and Morris water maze tests. Furthermore, the expression ration of
apoptotic marker Bax and anti-apoptotic marker Bcl-2 in the hippocampus and prefrontal
cortex showed higher levels in HJV(−/−) mice. Our results suggested that deletion of HJV
gene could increase apoptosis in brain which might contribute to learning and memory
deficits in mutant mice. These results indicated that HJV(−/−) mice would be a useful
model to study cognitive impairment induced by iron overload in brain. 相似文献
90.
African swine fever(ASF) is an acute and highly contagious disease that causes severe economic losses to the swine industry. ASF is caused by infection of African swine fever virus(ASFV) in domestic pigs, leading to almost 100% mortality. However, no effective vaccines and pharmacologic treatment against ASF are available. ASF poses a severe threat to the swine industry and the economy. Here we summarize potential virus-host cell interaction mechanisms involving the suppression of innate and adaptive immune responses to ASFV entry and infection. These mechanisms include modulation of apoptosis, inhibition of inflammatory responses, reduction of IFN production, inhibition of autophagy, and suppression of MHC-I expression. Insights into immunoevasion strategies by ASFV may shed light on the development of vaccines, as well as preventive and therapeutic drugs. 相似文献