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1.
Conventional cancer therapies, the second leading cause of death worldwide, result in serious side effects and, at best, merely extend the patient''s lifespan by a few years. Searching for effective prevention is of high priority in both basic and clinical sciences. In recent decades natural products have been considered to be an important source of cancer chemopreventive agents. Red wine polyphenols, which consisted of various powerful antioxidants such as flavonoids and stilbenes, have been implicated in cancer prevention and that promote human health without recognizable side effects. Since resveratrol, a major component of red wine polyphenols, has been studied and reviewed extensively for its chemopreventive activity to interfere with the multi-stage carcinogenesis, this review focuses on recent progress in studies on cancer chemopreventive activities of red wine polyphenol extracts and fractions as well as other red wine polyphenols, like procyanidin B5 analogues and myricetin.  相似文献   

2.
Lung cancer may be prevented by a diet rich in fruits and vegetables as they are enriched with dietary antioxidant polyphenols, such as flavonoids, proanthocyanidins, lignans, stilbenes, and phenolic acids. Dietary polyphenols exert a wide range of beneficial biological functions beyond their antioxidative properties and are involved in regulation of cell survival pathways leading to anticarcinogenic and antimutagenic functions. There are sufficient evidence from in vitro, in vivo, and epidemiological studies to suggest that the dietary intervention of polyphenols in cancer prevention, including the chemopreventive ability of dietary polyphenols, act against lung carcinogens. Cohort and epidemiological studies in selected risk populations have evaluated clinical effects of polyphenols. Polyphenols have demonstrated three major actions: antioxidative activity, regulation of phase I and II enzymes, and regulation of cell survival pathways against lung carcinogenesis. They have also shown an inverse association of lung cancer occurrences among high risk populations who consumed considerable amounts of fruits and vegetables in their daily diet. In in vitro cell culture experimental models, polyphenols bind with electrophilic metabolites from carcinogens, inactivate cellular oxygen radicals, prevent membrane lipid peroxidation and DNA oxidative damage, and adduct formation. Further, polyphenols enhance the detoxifying enzymes such as the phase II enzymes, glutathione transferases and glucuronosyl transferases.  相似文献   

3.
Prostate cancer is the most prevalent disease affecting males in many Western countries, with an estimated 29,480 deaths in 2014 in the US alone. Incidence rates for prostate cancer deaths have been decreasing since the early 1990s in men of all races/ethnicities, though they remain about 60% higher in African Americans than in any other group. The relationship between dietary polyphenols and the prevention of prostate cancer has been examined previously. Although results are sometimes inconsistent and variable, there is a general agreement that polyphenols hold great promise for the future management of prostate cancer. Various dietary components, including polyphenols, have been shown to possess anti-cancer properties. Generally considered as non-toxic, dietary polyphenols act as key modulators of signaling pathways and are therefore considered ideal chemopreventive agents. Besides possessing various anti-tumor properties, dietary polyphenols also contribute to epigenetic changes associated with the fate of cancer cells and have emerged as potential drugs for therapeutic intervention. Polyphenols have also been shown to affect post-translational modifications and microRNA expressions. This article provides a systematic review of the health benefits of selected dietary polyphenols in prostate cancer, especially focusing on the subclasses of polyphenols, which have a great effect on disease prevention and treatment.  相似文献   

4.
The process of apoptosis is essential for maintaining the physiologic balance between cell death and cell growth. This complex process is executed by two major pathways that participate in activating an executioner mechanism leading to chromatin disintegration and nuclear fragmentation. Dysregulation of these pathways often contributes to cancer development and resistance to cancer therapy. Here, we review the most recent discoveries in apoptosis regulation and possible mechanisms for resensitizing tumor cells to therapy.  相似文献   

5.
目的探讨姜黄素(Curcumin)对人喉癌Hep-2细胞的生长抑制及诱导凋亡作用。方法将Hep-2细胞用含不同浓度姜黄素(3、6、12.5、25μmol/L)的培养基分别培养24和48h,采用MTT法检测其对细胞增殖的影响;台盼蓝染色法检测其对细胞活力的影响;流式细胞术检测其对细胞周期分布及细胞凋亡的影响;DNA琼脂糖凝胶电泳检测其对细胞DNA的影响。结果姜黄素可明显抑制Hep-2细胞增殖,且呈时间-剂量依赖性;可明显降低细胞活力,且呈剂量依赖性;可使细胞阻滞在G2/M期,并诱导细胞出现典型的凋亡峰,凋亡率呈时间-剂量依赖性;能使细胞DNA形成典型的DNA-Ladder。结论姜黄素对人喉癌Hep-2细胞增殖及细胞活力具有显著的抑制作用,并能诱导Hep-2细胞发生凋亡。  相似文献   

6.
Glutamine metabolism has been proved to be dysregulated in many cancer cells, and is essential for proliferation of most cancer cells, which makes glutamine an appealing target for cancer therapy. In order to be well used by cells, glutamine must be transported to cells by specific transporters and converted to glutamate by glutaminase. There are currently several drugs that target glutaminase under development or clinical trials. Also, glutamine metabolism restriction has been proved to be effective in inhibiting tumor growth both in vivo and vitro through inducing apoptosis, growth arrest and/or autophagy. Here, we review recent researches about glutamine metabolism in cancer, and cell death induced by targeting glutamine, and their potential roles in cancer therapy.  相似文献   

7.
目的探讨鱼藤素诱导乳腺癌MDA-MB-231细胞凋亡的作用及其与线粒体凋亡途径的关系。方法用不同浓度的鱼藤素处理MDA-MB-231细胞,MTT法检测鱼藤素对MDA-MB-231细胞的增殖抑制作用;AnnexinV-FITC/PI双染流式细胞术检测细胞的凋亡率;罗丹明123单染法观察细胞线粒体膜电位的变化;Western blot法检测细胞cyt-c、caspase-3蛋白的表达水平;分光光度法检测细胞caspase-3蛋白活性。结果鱼藤素对MDA-MB-231细胞的增殖具有明显的抑制作用,且呈时效、量效依赖性;800和1200nmol/L鱼藤素处理组的细胞早期凋亡率显著高于未处理组;鱼藤素处理后,细胞线粒体膜电位降低,细胞浆内cyt-c和caspase-3蛋白的表达水平及caspase-3活性均明显升高。结论鱼藤素对乳腺癌MDA-MB-231细胞具有显著的增殖抑制、诱导凋亡作用,其作用与线粒体膜电位降低、释放细胞色素c,从而激活caspase-3依赖途径有关。  相似文献   

8.
重点对植物多酚的不同提取方法及其原理进行概述,并对比不同提取方法的优缺点.  相似文献   

9.
Echinacoside is a natural compound with potent reactive oxygen species (ROS)-scavenging and anti-oxidative bioactivities, which protect cells from oxidative damages. As cancer cells are often under intense oxidative stress, we therefore tested if Echinacoside treatment would promote cancer development. Surprisingly, we found that Echinacoside significantly inhibited the growth and proliferation of a panel of cancer cell lines. Treatment of the human SW480 cancer cells with Echinacoside resulted in marked apoptosis and cell cycle arrest, together with a significant increase in active caspase 3 and cleaved PARP, and upregulation of the G1/S-CDK blocker CDKN1B (p21). Interestingly, immunocytochemistry examination of drug-treated cancer cells revealed that Echinacoside caused a significant increase of intracellular oxidized guanine, 8-oxoG, and dramatic upregulation of the double-strand DNA break (DSB)-binding protein 53BP1, suggesting that Echinacoside induced cell cycle arrest and apoptosis in SW480 cancer cells via induction of oxidative DNA damages. These results establish Echinacoside as a novel chemical scaffold for development of anticancer drugs.  相似文献   

10.
超声波协助提取茶多酚的工艺研究   总被引:5,自引:0,他引:5  
研究了在超声波协助下采用正交设计法优选茶多酚的提取工艺。结果表明,影响茶多酚提取率的最佳工艺条件为:浸提温度70℃;时间1.5 h;料液比20∶1;乙醇浓度70%。影响茶多酚含量的最佳工艺条件为:浸提温度80℃;时间1.5 h;料液比15∶1;乙醇浓度70%。这些结果为改善茶多酚的提取条件提供了实验基础。  相似文献   

11.
周文杰  鲍时安 《广东化工》2008,35(2):46-48,82
提取了苹果中的多酚成份,并对其防晒性能进行了研究,并和纳米二氧化钛、纳米氧化锌、新型防晒剂NT-200A、新型防晒剂NT-200B等紫外线屏蔽剂进行复合使用,研究其复合防晒性能。结果显示,多酚具有一定的防晒功能,加入其它防晒剂复配后制成防晒霜,得到较为理想的防晒产品。  相似文献   

12.
Herein we report novel pyrrole‐ and benzene‐based hydroxamates ( 8 , 10 ) and 2′‐aminoanilides ( 9 , 11 ) bearing the tert‐butylcarbamate group at the CAP moiety as histone deacetylase (HDAC) inhibitors. Compounds 8 b and 10 c selectively inhibited HDAC6 at the nanomolar level, whereas the other hydroxamates effected an increase in acetyl‐α‐tubulin levels in human acute myeloid leukemia U937 cells. In the same cell line, compounds 8 b and 10 c elicited 18.4 and 21.4 % apoptosis, respectively (SAHA: 16.9 %), and the pyrrole anilide 9 c displayed the highest cytodifferentiating effect (90.9 %). In tests against a wide range of various cancer cell lines to determine its antiproliferative effects, compound 10 c exhibited growth inhibition from sub‐micromolar (neuroblastoma LAN‐5 and SH‐SY5Y cells, chronic myeloid leukemia K562 cells) to low‐micromolar (lung H1299 and A549, colon HCT116 and HT29 cancer cells) concentrations. In HT29 cells, 10 c increased histone H3 acetylation, and decreased the colony‐forming potential of the cancer cells by up to 60 %.  相似文献   

13.
Inhibition of apoptosis leads to activation of cell survival factors (e.g., AKT) causes continuous cell proliferation in cancer. Apoptosis, the major form of cellular suicide, is central to various physiological processes and the maintenance of homeostasis in multicellular organisms. A number of discoveries have clarified the molecular mechanism of apoptosis, thus clarifying the link between apoptosis and cell survival factors, which has a therapeutic outcome. Induction of apoptosis and inhibition of cell survival by anticancer agents has been shown to correlate with tumor response. Cellular damage induces growth arrest and tumor suppression by inducing apoptosis, necrosis and senescence; the mechanism of cell death depends on the magnitude of DNA damage following exposure to various anticancer agents. Apoptosis is mainly regulated by cell survival and proliferating signaling molecules. As a new therapeutic strategy, alternative types of cell death might be exploited to control and eradicate cancer cells. This review discusses the signaling of apoptosis and cell survival, as well as the potential contribution of marine bioactive compounds, suggesting that new therapeutic strategies might follow.  相似文献   

14.
茶多酚是一种新型天然食品添加剂和新兴的医药保健品.医药保键用茶多酚对产品质量要求较高,采用本工艺得到的绿茶提取物茶多酚含量≥95%,儿茶素含量≥70%,咖啡因含量≤0.5%~1%,达到或超过医药保健用茶多酚产品的要求.  相似文献   

15.
天然抗氧化剂茶多酚的提取研究进展   总被引:2,自引:0,他引:2  
综述了茶多酚的提取方法研究进展,并且简要介绍其功能、性质和结构。  相似文献   

16.
朱鑫鑫  熊志勇  汪烈焰  王辉 《广东化工》2011,38(7):292+291-292,291
以绿茶茶末为原料,以乙醇为介质,用超声波协助法提取茶多酚,并通过改变浸提温度,浸提时间,料液比(茶醇比),溶剂浓度等条件对产品提取率的影响进行了探讨,获得最佳的提取条件。结果表明,超声波协助提取茶多酚最佳产率的工艺条件为:浸提温度60℃,浸提时间2gmin,料液比1:9,乙醇浓度60%。该方法与传统提取方法相比,提取率高,省溶剂,大大提高了提取效率。  相似文献   

17.
杨金伟  杨斌 《云南化工》2019,(3):108-109
茶多酚是茶叶的主要活性化合物,有效提取茶多酚,实现其综合利用具有十分重要的现实意义。初步探讨浸提次数、提取温度、不同浓度的提取液、不同的反应时间和茶叶的粉碎情况对茶多酚提取结果的影响。结果表明:70℃水浴为最佳提取温度,70%的甲醇水为最佳提取浓度,60min为最佳放置时间。  相似文献   

18.
Pogostemon cablin (PC) is a traditional herbal medicine used in the treatment of the common cold, nausea, diarrhea, and even for headaches and fever. However, the mechanisms underlying the anti-proliferative activity of PC in endometrial cancer (EC) cells have yet to be fully elucidated. This study investigated the anticancer effects of an aqueous extract of Pogostemon cablin (PCAE), specifically induced apoptosis in EC (Ishikawa) cells. Proliferation of EC cells following exposure to PCAE was assessed by an MTT assay. DNA content and the induction of cell cycle apoptosis were analyzed by flow cytometry (FACS Calibur). Protein caspase-3 and, -9 as well as AIF were investigated using Western blot. Our results demonstrate growth inhibition of Ishikawa cells by PCAE. Furthermore, caspase-3 activity caused PCAE-treated cell lines to accumulate in apoptosis. Gene expression profiling (GEP) results further suggest that, in addition to its known effects with regard to EC prevention, PCAE may also exert antitumor activity on established EC cells. Many previous studies have identified the chemo-preventive effects of natural plant materials and the potential role of these materials in chemotherapy. This current study used human EC Ishikawa cells to investigate the anti-tumor effects of PCAE in EC cells. Our results demonstrate that PCAE inhibits the growth of cancer cells and induces apoptosis, which suggests the potential applicability of PCAE as an antitumor agent.  相似文献   

19.
烟草废料中多酚类物质的浸提条件研究   总被引:4,自引:0,他引:4  
对烟草废料中多酚类物质的提取进行了探讨,对浸提溶剂的种类、料液比、浸提次数及浸提温度等条件进行了优化,同时研究了微波、超声波等不同处理方法对浸提效果的影响.实验结果表明,以丙酮和水(1:2)作为浸提剂效果较好,在料液比1:9,温度40℃,48h的条件下,浸出液中多酚类物质的浓度为4.13 mg·mL-1.而用超声波处理时,浸提时间缩短至5 min,浸提液中多酚的浓度为4.31 mg·mL-1;在用微波处理时所需时间更短(90s),浸提液中的多酚类浓度为4.99mg·mL-1.利用微波或超声波辅助处理,可以大幅度缩短浸提时间,提高浸提效率.  相似文献   

20.
目的探讨普洱茶提取物对人宫颈癌HeLa细胞系的诱导凋亡作用及其分子机制。方法应用不同浓度的普洱茶提取物(15、30、60、120、250、500μg/ml)作用HeLa细胞后,采用MTT法检测其对细胞增殖的影响;DAPI染色法分析细胞凋亡形态学变化;Annexin V-FITC/PI双染流式细胞术检测细胞早期凋亡;Western blot分析pro-caspase-3和pro-caspase-9的变化。结果普洱茶提取物对HeLa细胞的增殖具有明显的抑制作用,且呈浓度依赖性;经普洱茶提取物处理的细胞荧光显微镜下可见典型的凋亡形态学变化,细胞早期凋亡率显著高于未处理的细胞(P<0.05);经普洱茶提取物处理的细胞pro-caspase-3和pro-caspase-9均被活化。结论普洱茶提取物具有可以诱导HeLa细胞凋亡的天然活性成分,且凋亡途径可能依赖于caspase-3、caspase-9相关的线粒体凋亡途径。  相似文献   

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