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11.
Lycopene is a nutraceutical with health-promoting and anti-cancer activities, but due to a lack of evidence, there are no recommendations regarding its use and dosage. This review aimed to evaluate the benefits of lycopene supplementation in cancer prevention and treatment based on the results of in vivo studies. We identified 72 human and animal studies that were then analysed for endpoints such as cancer incidence, improvement in treatment outcomes, and the mechanisms of lycopene action. We concluded that the results of most of the reviewed in vivo studies confirmed the anti-cancer activities of lycopene. Most of the studies concerned prostate cancer, reflecting the number of in vitro studies. The reported mechanisms of lycopene action in vivo included regulation of oxidative and inflammatory processes, induction of apoptosis, and inhibition of cell division, angiogenesis, and metastasis formation. The predominance of particular mechanisms seemed to depend on tumour organ localisation and the local storage capacity of lycopene. Finally, there is a need to look for predictive factors to identify a population that may benefit from lycopene supplementation. The potential candidates appear to be race, single nucleotide polymorphisms in carotene-cleaving enzymes, some genetic abbreviations, and insulin-like growth factor-dependent and inflammatory diseases. 相似文献
12.
番茄红素对大鼠非酒精性脂肪肝的作用研究 总被引:7,自引:0,他引:7
目的观察番茄红素对非酒精性脂肪肝的影响并探讨其作用机制。方法用高脂饲料诱导建立大鼠脂肪肝模型,再给予番茄红素治疗,观察各组大鼠血清或组织中天门冬酸氨基转移酶(AST)、谷氨酸氨基转移酶(ALT)、超氧化物歧化酶(SOD)、丙二醛(MDA)、甘油三酯(TG)、胆固醇(CHO)、高密度脂蛋白胆固醇(HDL—C)、低密度脂蛋白胆固醇(LDL—C)、游离脂肪酸(FFA)、胆碱酯酶(CHE)的活性或含量。并观察肝组织病理学改变情况。结果与自然恢复组比较,番茄红素给药组血清AST及ALT的活性显著降低;肝组织中SOD活性升高、MDA含量降低;血清中TG,CHO,LDL—C及FFA水平降低,HDL—C水平升高;血清及肝组织中的CHE活性降低;肝脏脂肪沉积减少,肝组织的病理改变显著。结论番茄红素能够减轻非酒精性脂肪肝的病变程度,其机制可能与其所具有的调血脂及抗氧化等作用有关。 相似文献
13.
番茄红素对高脂兔血管脂质过氧化损伤的影响及机制探讨 总被引:6,自引:0,他引:6
目的:观察番茄红素对高脂喂饲所致家免主动脉脂质过氧化损伤的影响。方法:采用高脂喂饲模型,将30只新西兰家兔随机分为3组:对照组、高脂模型组和番茄红素组,分别给予普通饲料和高脂饲料喂养,番茄红素组另加用番茄红素;于实验开始前1d和开始后第2、4、6、8周末取空腹血测定血清总胆固醇、甘油三酯、高密度脂蛋白胆固醇、血清超氧化物歧化酶活性、丙二醛含量、血清一氧化氮含量和一氧化氮合酶活性。实验结束后,苏丹Ⅳ染色和HE染色观察主动脉血管病理变化。结果:与高脂模型组相比,番茄红素组血清甘油三酯含量减低;血清超氧化物歧化酶活性明显增加;血清丙二醛的含量减少;一氧化氮含量增加;主动脉脂质斑块面积减少。结论:番茄红素对兔主动脉脂质过氧化损伤具有较好的保护作用,能减轻高脂兔动脉粥样硬化病变形成。降甘油三酯,抗脂质过氧化损伤及保护血管内皮功能可能是番茄红素产生抗动脉粥样硬化作用的重要机制。 相似文献
14.
目的探讨番茄红素对人体的安全性和抗氧化作用。方法将120名健康志愿者按血清丙二醛(MDA)含量随机分为试食组和对照组,试食组连续服用番茄红素90 d,对照组服用安慰剂,测定2组人群血清中MDA含量及超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性和安全性指标。结果试食前后,试食组志愿者血清MDA含量分别为4.06和3.61 nmoL/mL,下降11.03%;SOD活性分别为90.7和96.7 U/mL,上升6.80%;GSH-Px活性分别为122.6和136.9 NU/mL,上升11.74%,与对照组比较,差异均有统计学意义(P<0.01);试食前后2组人群各项安全性指标均在正常范围内。结论番茄红素可提高人体抗氧化能力,且对人体健康无损害。 相似文献
15.
《International journal of food sciences and nutrition》2013,64(3):239-249
The stem, leaf, and root of Tinospora cordifolia (willd.) have been highly exploited for medicinal preparations; however, the nutritional and nutraceutical potential of its attractive red berries (fruits) have not so far been studied. Pigments, berberine (107.0 mg/100 g) and lycopene (50.8 mg/100 g), were identified in the deseeded fruit. Total phenol content in the fruit was 3.2 mg gallic acid equivalent/g. The IC50 of DPPH√ (82, and 468 ppm) and OH√ (100, and 1,000 ppm) scavenging activity, and the EC50 of reducing power (2,616, and 1,472 ppm) of hexane and methanol extracts, respectively, were observed. Oxygen radical absorbance capacities of the fruit extracts (150 and 300 ppm) were 1,107 and 2,614 μM trolox equivalent/g, respectively. Nutrient composition including carbohydrate (18.4%), proteins (1.5%), lipids (6%) of which ~62% was unsaturated fatty acids, vitamins like ascorbic acid (0.24 μg), niacin (0.7 mg), and tocopherols (2.4 mg) in 100 g fruits were determined. Potassium content was 1.2 g/100 g dry tissue of berries. These findings show that components of T. cordifolia fruit could be bioactive and used in food, pharmaceutical, and cosmetics. 相似文献
16.
Padma T. Uppala Tixieanna Dissmore Benjamin H. S. Lau Tracy Andacht Sujatha Rajaram 《Phytotherapy research : PTR》2013,27(4):595-601
Lycopene, a red pigmented carotenoid present in many fruits and vegetables such as tomatoes, has been associated with the reduced risk of breast cancer. This study sought to identify proteins modulated by lycopene during cell proliferation of the breast cancer cell line MCF‐7 to gain an understanding into its mechanism of action. MCF‐7 breast cancer cells and MCF‐10 normal breast cells were treated with 0, 2, 4, 6, 8, and 10 μM of lycopene for 72 h. 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) tetrazolium reduction assay was used to measure cell proliferation and two‐dimensional fluorescence difference gel electrophoresis to assess the changes in protein expression, which were identified using MALDI‐ToF/ToF (matrix‐assisted laser desorption ionization tandem time‐of‐flight) and Mascot database search. MTT and cell proliferation assays showed that lycopene selectively inhibited the growth of MCF‐7 but not MCF‐10 cells. Difference gel electrophoresis analysis revealed that proteins in the MCF‐7 cells respond differently to lycopene compared with the MCF‐10 cells. Lycopene altered the expression levels of proteins such as Cytokeratin 8/18 (CK8/18), CK19 and their post translational status. We have shown that lycopene inhibits cell proliferation in MCF‐7 human breast cancer cells but not in the MCF‐10 mammary epithelial cells. Lycopene was shown to modulate cell cycle proteins such as beta tubulin, CK8/18, CK19 and heat shock proteins. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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18.
目的:通过在人精子冷冻保护液中添加不同浓度的番茄红素,研究番茄红素对精子冷冻损伤的可能保护作用及机制。方法:选择吉林省人类精子库捐精者的精液标本25份,每份精液一式4份,3∶1加入冷冻保护液后混匀,不含番茄红素者设为对照组(Ly0),而Ly2、Ly5、Ly10实验组混合液中分别含有2、5、10μmol/L的番茄红素,冷冻复苏精液进行常规分析,采用流式细胞术分析冻融后各组精子的凋亡率;采用硫代巴比妥酸(TBA)比色法检测精子中脂质过氧化产物丙二醛(MDA)浓度。利用JC-1标记法检测线粒体膜电位。结果:冻融后各组精子运动参数较新鲜精液参数均明显下降(P<0.01),Ly5组冻融后精子凋亡率[(25.68±4.36)%]较对照组[(33.26±4.78)%]显著下降(P<0.05);Ly5组线粒体膜电位水平[(66.18±14.23)%]显著高于对照组[(55.24±12.31)%],P<0.05;Ly2、Ly5、Ly10组的MDA水平与对照组比较,无统计学差异(P>0.05)。结论:在精液冷冻保护液中添加一定浓度的番茄红素可以减少线粒体氧化损伤,减轻活性氧对精子质膜的氧化应激损伤,从而提高精子的抗凋亡能力。 相似文献
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20.
目的研究番茄红素对大鼠肺缺血再灌注损伤的保护作用,并考察其作用机制。方法取120只SD大鼠随机分为假手术组、模型组、舒血宁注射液(4 mg/kg)组以及番茄红素5、10、20 mg/kg组,每组20只。除假手术组外采用夹闭左肺门45 min后松夹的方法制备大鼠肺缺血再灌注损伤模型。再灌注2 h后,分别测定各组大鼠肺组织湿质量/干质量比值;通过苏木精–尹红(HE)染色观察肺组织病理学改变;原位末端标记(TUNEL)法观察肺组织细胞凋亡并计算凋亡指数(AI);检测血清中丙二醛(MDA)含量和髓过氧化物酶(MPO)活性;测定肺组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性。结果与模型组比较,番茄红素10、20 mg/kg组肺组织湿质量/干质量比值显著降低(P0.05、0.01),肺组织病变显著改善,肺组织细胞凋亡状况明显改善;血清中MDA含量和MPO活性显著降低(P0.05、0.01),肺组织中SOD、CAT活性显著升高(P0.05、0.01)。其中番茄红素20 mg/kg组对肺缺血再灌注损伤大鼠肺组织病变改善最为显著、细胞凋亡状况改善以及凋亡指数降低效果最为显著,对血清中MDA含量和MPO活性显著降低效果更加显著、肺组织中GSH-Px活性显著升高(P0.01)。结论番茄红素能够有效降低肺组织湿质量/干质量比值,改善肺组织病变,抑制肺组织细胞凋亡、降低凋亡指数,提示番茄红素对大鼠肺缺血再灌注损伤具有剂量相关性的保护作用,其作用机制可能与番茄红素能够有效改善机体抗氧化酶活性、抑制氧化应激损伤有关。 相似文献