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排序方式: 共有1359条查询结果,搜索用时 0 毫秒
1.
目的 探究白藜芦醇对脑小血管疾病(CSVD)大鼠神经细胞损伤及免疫因子白细胞介素-6(IL-6)、白细胞介素-10(IL-10)水平的影响。方法 将60只CSVD大鼠分为假手术组、模型组和治疗组,每组20只。通过水迷宫实验测试大鼠神经认知功能,HE染色观察大鼠海马组织病理学改变,TUNEL染色检测大鼠海马组织神经细胞凋亡率,Western blotting检测大鼠海马组织BAX/BCL-2、IL-6、IL-10蛋白的表达,酶联免疫吸附试验(ELISA)检测外周血IL-6、IL-10、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽(GSH)和丙二醛(MDA)水平。结果 模型组大鼠神经行为评分高于治疗组(P <0.05)。模型组大鼠穿越次数和停留时间少于假手术组(P <0.05),治疗组大鼠穿越次数和停留时间较模型组增加(P <0.05)。模型组大鼠海马组织神经细胞凋亡率、BAX/BCL-2蛋白表达比值高于假手术组(P <0.05),治疗组大鼠海马组织神经细胞凋亡凋亡率、AX/BCL-2蛋白表达比值低于模型组(P <0.05)。与假手术组比较,模型组...  相似文献   
2.
Resveratrol, a natural polyphenolic phytoalexin, has been considered as a potential anti-inflammatory agent because of its suppressive effect on nuclear factor-kappaB (NF-kappaB). However, we recently found that treatment of glomerular mesangial cells with resveratrol significantly and dose-dependently enhanced NF-kappaB activation triggered by proinflammatory cytokines. This finding was evidenced by different reporter assays as well as by expression of an endogenous NF-kappaB-dependent gene, intercellular adhesion molecule-1. The NF-kappaB promoting effect of resveratrol was also observed in renal tubular LLCPK1 cells, but not in HepG2 hepatoma cells. In all cell types tested, treatment with resveratrol alone did not affect NF-kappaB activity. The enhanced activation of NF-kappaB by resveratrol progressed for at least 24 h and was accompanied by sustained down-regulation of an endogenous NF-kappaB inhibitor, IkappaBbeta, but not IkappaBalpha. Although expression of inducible nitric oxide synthase was suppressed by resveratrol, nitric oxide, a negative regulator of NF-kappaB, was not involved in the regulation of NF-kappaB by resveratrol. These data elucidated, for the first time, that resveratrol may enhance activation of NF-kappaB under certain circumstances.  相似文献   
3.
Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer.  相似文献   
4.
Among therapeutic approaches that have been investigated, targeting of receptors implicated in managing neuroinflammation has been described. One such family of receptors comprises the formyl peptide receptors (FPRs) whose ligands could play a role in host defense. The murine FPR gene family includes at least six members while in humans there are only three. The two most important members are the Fpr1 and Fpr2. Fpr1encodes murine FPR1, which is considered the murine orthologue of human FPR. Resveratrol, a non-flavonoid polyphenol rich in red wine and grapes, apart from its beneficial health effects and anti-inflammatory properties, has been reported to reduce neuroinflammation in different neurodegenerative disease models. Resveratrol anti-inflammatory responses involve the activation of the protein deacetylase sirtuin 1 (SIRT1) gene. In this work we have investigated in an LPS-based murine model of neuroinflammation the role of FPR1, examining not only if this receptor undergoes a reduction of its expression during neuroinflammation, but also whether treatment with resveratrol was able to modulate its expression leading to an amelioration of neuroinflammatory picture in a murine model of neuroinflammation. Results of this work showed that FPR1 together with SIRT1 resulted upregulated by resveratrol treatment and that this increase is associated with an amelioration of the neuroinflammatory picture, as demonstrated by the induction of IL-10 and IL1-RA expression and the downregulation of proinflammatory mediators, such as TNF-α and IL-1β. The expression and the modulation of FPR1 by resveratrol may be evaluated in order to propose a novel anti-inflammatory and pro-resolving therapeutic approach for the reduction of the detrimental effects associated with neuro-inflammation based neurodegenerative diseases and also as a promising strategy to promote human health by a diet rich in antioxidative bioactive compounds.  相似文献   
5.
肖振  李盛华 《中草药》2023,54(5):1526-1539
目的 基于生物信息学分析筛选激素性股骨头坏死(steroid induced osteonecrosis of femoral head,SONFH)中涉及血管生成相关的基因,进一步探讨其作用机制并筛选靶向中药活性成分。方法 通过Perl语言和R软件处理GEO数据,获得SONFH的关键差异基因,使用David工具进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)分析。然后使用STRING平台和Cytoscape软件分析蛋白互作关系,用MCODE和CytoHubba插件识别重要基因簇模块和核心基因,并进一步验证。使用CTD数据库搜索靶向核心基因的中药活性成分并用autodock vina软件进行分子对接,以及探索核心基因与SONFH的相互作用。利用激素诱导人股骨头骨微血管内皮细胞(bone microvascular endothelial cells,BMECs),通过CCK-8、细胞划痕实验和Transwell实验观察白藜芦醇对细胞增殖及迁移的影响,通过Western ...  相似文献   
6.
毛穗藜芦中茋类化合物的化学研究   总被引:1,自引:0,他引:1  
目的:对毛穗藜芦根茎进行化学成分研究。方法:采用柱层析和薄层层析法进行分离,用UV,IR,MS,1HNMR等光谱技术鉴定化合物的结构。结果:得到2个类化合物,为白藜芦醇和2,3′,4,5′四羟基。结论:为首次从该植物中分离得到  相似文献   
7.
白藜芦醇对小鼠免疫系统调节作用的研究   总被引:11,自引:0,他引:11  
目的研究白藜芦醇对小鼠免疫功能的影响。方法通过碳粒廓清试验,测定白藜芦醇对小鼠腹腔巨噬细胞功能的影响;通过比色法测定鸡红细胞免疫后小鼠血清溶血素抗体水平,研究白藜芦醇对小鼠体液免疫的影响。结果白藜芦醇30 mg/kg和15 mg/kg剂量对环磷酰胺致小鼠细胞免疫抑制有对抗作用,能使免疫功能低下小鼠吞噬指数和吞噬系数得到恢复;白藜芦醇30 mg/kg剂量可对抗环磷酰胺致小鼠体液免疫抑制,提高血清溶血素抗体水平。结论白藜芦醇对小鼠免疫功能有较好的调节作用。  相似文献   
8.
探讨白黎芦醇(Res)对人晶状体上皮细胞(HLEC)增殖的影响。体外培养HLEC 24h,加入重组人碱性成纤维细胞生长因子(终浓度20μg/L)使HLEC处于增殖状态。MTT比色法检测不同浓度Res作用于增殖状态的HLEC 24h及25mg/L Res作用于增殖状态HLEC 6h、12h、24h、48h对细胞增殖的影响。结果表明不同浓度的Res,25mg/L Res于不同时间对增殖状态的HLEC有明显的抑制作用,并具有时间及剂量依赖关系。提示Res能够明显抑制HLEC增殖,有望成为防治后发性白内障的有效药物。  相似文献   
9.
目的 :研究大鼠血浆中白藜芦醇含量的测定方法。方法 :采用液 -液萃取反相高效液相色谱梯度洗脱法对大鼠血浆样品中的白藜芦醇含量进行测定。结果 :因为血浆中白藜芦醇在 0 .0 0 35~1.4 0 0mg·L-1线性范围内关系良好 (r =0 .9998) ,最低定量限为 0 .0 35mg·L-1;低、中、高三种浓度下的回收率、日内及日间精密度均符合方法学要求。故用本法测定大鼠一次性灌服虎杖提取物后白藜芦醇的血药浓度并计算药代动力学参数 ,半衰期t1 2 =11.5min ,达峰时间tmax=10 .0min ,达峰浓度Cmax=1.93mg·L-1。结论 :本法符合生物样品分析要求 ,可用于体内白藜芦醇浓度测定  相似文献   
10.
Diabetes incidence is rising globally at an accelerating rate causing issues at both the individual and societal levels. However, partly inspired by Ayurvedic medicine, a naturally occurring compound called pterostilbene has been demonstrated to protect against diabetes symptoms, though mainly in rats. The purpose of this study was to investigate the putative protective effect of pterostilbene on the two main aspects of diabetes, namely insulin resistance and decreased insulin secretion, in mice. To accomplish this, we employed diet-induced obese as well as streptozotocin-induced diabetic C57BL/6NTac mice for fasting glucose homeostasis assessment, tolerance tests and pancreas perfusions. In addition, we used the polygenic model of diabetes TALLYHO/JngJ to assess for prevention of β-cell burnout. We found that the diet-induced obese C57BL/6NTac mice were insulin resistant, but that pterostilbene had no impact on this or on overall glucose regulation. We further found that the reported protective effect of pterostilbene against streptozotocin-induced diabetes was absent in C57BL/6NTac mice, despite a promising pilot experiment. Lastly, we observed that pterostilbene does not prevent or delay onset of β-cell burnout in TALLYHO/JngJ mice. In conjunction with the literature, our findings suggest variations in the response to pterostilbene between species or between strains of species.  相似文献   
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