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1.
Prostate cancer (PCa) is a reproductive system cancer in elderly men. We investigated the effects of betel nut arecoline on the growth of normal and cancerous prostate cells. Normal RWPE-1 prostate epithelial cells, androgen-independent PC-3 PCa cells, and androgen-dependent LNCaP PCa cells were used. Arecoline inhibited their growth in dose- and time-dependent manners. Arecoline caused RWPE-1 and PC-3 cell cycle arrest in the G2/M phase and LNCaP cell arrest in the G0/G1 phase. In RWPE-1 cells, arecoline increased the expression of cyclin-dependent kinase (CDK)-1, p21, and cyclins B1 and D3, decreased the expression of CDK2, and had no effects on CDK4 and cyclin D1 expression. In PC-3 cells, arecoline decreased CDK1, CDK2, CDK4, p21, p27, and cyclin D1 and D3 protein expression and increased cyclin B1 protein expression. In LNCaP cells, arecoline decreased CDK2, CDK4, and cyclin D1 expression; increased p21, p27, and cyclin D3 expression; had no effects on CDK1 and cyclin B1 expression. The antioxidant N-acetylcysteine blocked the arecoline-induced increase in reactive oxygen species production, decreased cell viability, altered the cell cycle, and changed the cell cycle regulatory protein levels. Thus, arecoline oxidant exerts differential effects on the cell cycle through modulations of regulatory proteins.  相似文献   
2.
Oral submucous fibrosis (OSF) is known as a potentially malignant disorder, which may result from chemical irritation due to areca nuts (such as arecoline). Emerging evidence suggests that fibrogenesis and carcinogenesis are regulated by the interaction of long noncoding RNAs (lncRNAs) and microRNAs. Among these regulators, profibrotic lncRNA H19 has been found to be overexpressed in several fibrosis diseases. Here, we examined the expression of H19 in OSF specimens and its functional role in fibrotic buccal mucosal fibroblasts (fBMFs). Our results indicate that the aberrantly overexpressed H19 contributed to higher myofibroblast activities, such as collagen gel contractility and migration ability. We also demonstrated that H19 interacted with miR-29b, which suppressed the direct binding of miR-29b to the 3′-untranslated region of type I collagen (COL1A1). We showed that ectopic expression of miR-29b ameliorated various myofibroblast phenotypes and the expression of α-smooth muscle actin (α-SMA), COL1A1, and fibronectin (FN1) in fBMFs. In OSF tissues, we found that the expression of miR-29b was downregulated and there was a negative correlation between miR-29b and these fibrosis markers. Lastly, we demonstrate that arecoline stimulated the upregulation of H19 through the transforming growth factor (TGF)-β pathway. Altogether, this study suggests that increased TGF-β secretion following areca nut chewing may induce the upregulation of H19, which serves as a natural sponge for miR-29b and impedes its antifibrotic effects.  相似文献   
3.
李卫  郑成 《广东化工》2007,34(5):23-25
采用高压耦合纤维素酶水解技术软化槟榔壳。研究表明,高压处理有助于纤维组织的软化。实验得出最佳酶解温度为50℃,最佳酶解时间5 h,纤维素酶的最适用量为30 FIU/g;pH=4.8时纤维素酶对槟榔壳纤维水解效果最佳。  相似文献   
4.
槟榔生理效应研究进展   总被引:6,自引:0,他引:6  
槟榔是棕榈科植物槟榔的干燥成熟种子,含有多种人体所需的营养元素以及多种生理活性成分,是一种常用的中药。在国内外,槟榔果作为一种嗜好品-槟榔嚼块的主料而被广泛的使用。从槟榔的临床药用、抗菌驱虫、对神经系统、消化系统、心脑血管系统的作用以及其的遗传及细胞毒性等方面对槟榔生理效应的研究加以综述,并对其的发展前景作了探讨,以期让基础科研人员、公共卫生工作者以及广大槟榔嗜好者对槟榔在人类健康中的作用有更深入的了解。  相似文献   
5.
目的评定气相色谱法测定食用槟榔中环己基氨基磺酸钠(又名甜蜜素)的不确定度评定方法。方法根据气相色谱法定量测定食用槟榔中甜蜜素含量的测定原理,较全面的考虑整个测定过程的不确定度来源,建立结果不确定度评定的数学模型,并探讨其测定结果不确定度。结果在95%的置信区间下,当槟榔中甜蜜素含量为6.19 g/kg时,其扩展不确定度为0.18 g/kg, k=2。结论槟榔中甜蜜素的检测不确定度主要来源为标准曲线的拟合。  相似文献   
6.
鲜食槟榔的护绿保鲜研究   总被引:2,自引:0,他引:2  
对鲜槟榔果的护绿保鲜进行了研究。试验表明 ,在鲜食槟榔制作中 ,由于鲜槟榔果色泽变化的敏感性 ,采用热烫、微波、冷藏工艺或应用柠檬酸、山梨酸钾、对羟基苯甲酸乙酯 (尼泊金乙酯 )处理 ,都无法满足制作要求。试验选择了采用质量分数为 0 .3 %的护绿保鲜剂溶液浸泡鲜槟榔2 4h、入味保护后真空包装 ( -0 .1MPa)的工艺。结果 3 0℃下产品货架期可达 4个月。  相似文献   
7.
The antioxidant activity of methanol extract/fractions of leaf, bark, and heartwood of Acacia catechu was evaluated by various antioxidant assays, including free radical, superoxide and hydroxyl radical, reducing power, metal ion chelation, as well as hydroxyl radical induced DNA strand scission. The leaf, bark, and heartwood powder was extracted in methanol and the lyophilized methanol extract was fractionated with different solvents in the order of increasing polarity. The results indicate that ethyl acetate fraction of heartwood has the highest antioxidant capacities, presenting lower EC(50) values particularly in free radical scavenging activity, including DPPH radicals (4.76 ± 0.14 μg/mL), superoxide anions (26.21 ± 0.79 μg/mL), and hydroxyl radicals (33.69 ± 1.42 μg/mL), in direct assay systems. Reducing power was also highest in ethyl acetate fraction of heartwood (EC(50) of 79.05 ± 1.02 μg/mL). As for the chelating power on ferrous ions, leaf extract was more effective than bark and heartwood extracts. Furthermore, the ethyl acetate and acetone fractions of heartwood significantly protected pBR322 supercoiled plasmid DNA against strand scission induced by hydroxyl radicals in a Fenton's reaction mixture. PRACTICAL APPLICATION: The present investigation suggests that the three organs of A. catechu differ significantly in their antioxidant potential as seen in the DPPH radical scavenging assay, reducing power assay, metal ion chelating assay, superoxide radical scavenging assay and hydroxyl radical scavenging assay. Further, our results showed that crude methanol extract and ethyl acetate fraction of heartwood of A. catechu might have a good potential as a source for natural health products due to its antioxidant and DNA protective activities.  相似文献   
8.
采用甲醇超声提取槟榔嫩果中的儿茶素,先用石油醚除去杂质,再用乙酸乙酯萃取,提取物经抽真空浓缩,高效液相色谱- 质谱联用法测定。结果表明:槟榔嫩果中儿茶素类组分为(+)- 儿茶素和表没食子儿茶素没食子酸酯。  相似文献   
9.
以海南产槟榔鲜果为原料,制备槟榔提取物,研究槟榔提取物对小白鼠体内的抗氧化作用,通过体外实验筛选出来活性较好的提取物,将其作为受试物,以血清SOD及血清MDA水平为评价指标,进行小白鼠体内抗氧化作用研究。结果表明,槟榔粗提取物、乙酸乙酯萃取物和水溶出物三种组分对羟自由基(·OH)具有良好的清除作用,清除率均在53%以上。三种受试物的各个剂量均能显著提高小白鼠的血清SOD水平(p<0.05);而除乙酸乙酯萃取物高剂量作用效果不显著外(p>0.05),其他各受试物的各个剂量均能显著降低实验动物的血清MDA浓度(p<0.05)。槟榔提取物在小白鼠体内具有良好的抗氧化活性作用。  相似文献   
10.
Fenton氧化/强化混凝法预处理槟榔废水的试验研究   总被引:1,自引:0,他引:1  
采用Fenton氧化/强化混凝法对湖南某食用槟榔生产排放的废水进行预处理实验研究.实验结果表明:采用Fenton试剂,在初始pH值为5.0,H202投加量为247.5 g/L,Fe2投加量为1.40 g/L,反应时间为2h的条件下,CODcr去除率达到88.56%,色度去除率达到83.33%.继续采用10%的氢氧化钠对上清液进行强化混凝处理,在调节pH为9.0,反应时间为10 min的条件下,出水的CODcr可降至1980.0 mg/L,色度可降至20倍,颜色清澈,极大的消减了污染负荷,达到了良好的预处理效果.  相似文献   
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