Antioxidant activity of Areca catechu extracts in human hepatocarcinoma HepG2 cell lines

The effect of aqueous and various organic extracts from the different parts of Areca catechu L. (Arecaceae) on oxidative DNA damage in human hepatocarcinoma HepG2 cells was investigated using single cell gel electrophoresis (comet) assay. Comparison of a series of organic extracts from the nut husk and different parts of this plant was performed. Incubation of methanol extract of Areca nut husk showed a dose-dependent inhibition of comet formation while other solvent extracts did not. Significant protection of H₂O₂-induced DNA damage was observed at 0.1% w/v concentration which was at the same level of protection by 1 μM butylated hydroxytoluene (BHT). The age of Areca catechu nut husk also played important role in chemical constituents exhibiting antioxidation since only two out of five different ages of husks displayed anti-oxidative effects in the comet assay. Among the different parts of this plant that were tested, the nut husk was the only consistent part that demonstrated antioxidant activity.     

槟榔与焦槟榔的红外指纹图谱研究

目的：探讨槟榔药材炒焦炮制前、后的红外光谱指纹图谱特性及化学成分的变化。方法：采用红外光谱法对槟榔与焦槟榔药材进行检测,并对其特征峰进行归属。结果：获得了槟榔与焦槟榔药材的红外指纹图谱与特征吸收峰、鉴别特征峰,并找到其炮制前、后红外光谱指纹图谱与化学成分的变化规律。结论：该法具有简便、快速、灵敏的特点,可作为槟榔与焦槟榔药材定性检测与成分比对的分析方法,并为其质量控制提供依据。     

Expression of p53 protein correlates with decreased survival in patients with areca quid chewing and smoking-associated oral squamous cell carcinomas in Taiwan

Expression of p53 protein was examined in oral squamous cell carcinoma (SCC) from patients who were areca quid (AQ) chewers and/or tobacco smokers, using anti-p53 antibodies with an immunoperoxidase technique. Positive p53 stain was observed in 47 of 81 (58%) cases of oral SCC. p53 overexpression was found to higher in patients without AQ chewing and smoking habits than in patients with these two habits (80% vs 52%, P=0.076). No significant correlation was found between p53 expression and the patients' age, sex, cancer location, clinical staging, primary tumor TNM status, or histological differentiation of SCC. The Kaplan-Meier analysis showed that the prognosis for patients with p53-negative tumors was significantly better than that for patients with p53-positive tumors (P<0.05). A significant correlation was also observed between positive lymph node status and poor prognosis (P<0.05). These results suggest that p53 may serve as an adjuvant marker of poor survival in patients with oral SCCs in Taiwan.     

儿茶提取物抗甲型流感病毒作用的实验研究

目的　研究从中药儿茶中提取的药物成分抗甲型流感病毒的作用。方法　用狗肾传代MDCK细胞培养法观察儿茶提取物抑制甲型流感病毒的致细胞病变作用;用鸡胚培养法观察儿茶提取物抑制甲型流感病毒增生的作用;用红细胞凝集试验观察儿茶提取物体外直接抑制甲型流感病毒的作用。结果　1)儿茶提取物的细胞毒性较低,可有效抑制甲型流感病毒感染细胞(P<0.05);2)儿茶提取物在一定范围内可明显抑制甲型流感病毒在鸡胚内的增生,经红细胞凝集试验测定抑制病毒效价为8倍或8倍以上;3)儿茶提取物直接与甲型流感病毒作用后可抑制病毒血凝效价达16 倍以上。结论　儿茶提取物具有很好的抗甲型流感病毒的作用。     

酸浆醇提取物诱导人食管癌细胞凋亡的实验研究

目的探讨酸浆醇提取物(ethanol extracts of physalis alkekengi linn,EPL)能否诱导食管癌细胞株EC-1.71凋亡。方法用显微镜观察经EPL作用24、48、72 h后的EC-1.71细胞生长状况;流式细胞术检测EC-1.71细胞线粒体膜电位的变化及细胞凋亡率;western blot检测EC-1.71细胞PARP(poly ADP-ribose polymerase)裂解状况。结果在EPL作用下,EC-1.71细胞数量减少,细胞间接触疏松,凋亡细胞随着药物作用时间的延长而增多。流式细胞术结果表明,EPL作用后的细胞线粒体膜电位(△ψm)降低。与对照组比较,差异有统计学意义(P均<0.05)。作用48、72 h的细胞凋亡率随药物作用时间的延长而增高(P均<0.05)。western blot结果表明,在EPL作用48 h时可检测到相对分子量(Mr)为89 000的PARP片段。结论 EPL可以诱导EC-1.71细胞发生凋亡,其凋亡程度呈时间依赖性。     

Impairment of thymocyte function via induction of apoptosis by areca nut extract

Abstract

Areca quid (AQ) chewing is a popular oral habit, especially in Southeast Asia cultures, in which children may be engaged in the addictive habit early in their lives. Extracts of areca nuts, the main component of AQ, have been shown to affect the functionality of T-cells. However, the potential influence of ANE on the development of T-cells is unknown. This study, therefore, investigated the impact of areca nut extracts (ANE) on thymocytes and the potential mechanisms of action. Mice administered intraperitoneally with ANE at 1, 5, or 25?mg/kg daily for 5 days showed significant dose-dependent reductions in thymocyte viability. A marked decrease in the total number of thymocytes and the proportion of thymic CD4⁺CD8⁺ cells was observed in the 25?mg ANE/kg-treated mice, whereas the proportion of CD4 and CD8 single positive and CD4^?CD8^? cells was significantly increased. Further examination on the functionality of thymocytes showed that ANE suppress IL-2 production both ex vivo and in vitro. These results suggest that ANE may attenuate the development and functionality of thymic T-cells. ANE also directly induced apoptosis in thymic T-cells through activation of casapase-3 and apoptosis inducing factor (AIF). Collectively, the data suggested that the thymus is a sensitive target to ANE. Early exposure to ANE may interfere with the development and functionality of thymic T-cells.     

Expression of phosphorylated Akt in oral carcinogenesis and its induction by nicotine and alkaline stimulation

Background:  In Taiwan, it is well documented that cigarette smoking and areca nut chewing contribute to the risk of oral squamous cell carcinoma (OSCC). The role of phosphorylated Akt (p-Akt) in oral carcinogenesis induced by nicotine and alkaline environments was investigated.
Method:  Immunohistochemistry (IHC) was used to detect p-Akt expression in cancerous ( n  = 30) precancerous ( n  = 30), and normal mucosa tissues ( n  = 10). Western blotting was used to detect time-dependent induction of p-Akt by 100 μM nicotine in normal human bronchial epithelial cell (NHBE), normal human oral keratinocytes (NHOK), immortalized human epithelial cells (HaCaT) and OEC-M1 cells, dose-dependent induction of p-Akt in OEC-M1 and HaCaT cells and pH effect of p-Akt in OEC-M1. The unpaired t -test and the Fisher's exact test were used to analyze the p-Akt immunoreactivity in various groups and its association with clinicopathological parameters.
Results:  Higher p-Akt expression in cancerous group than in normal mucosa ( P  = 0.0002) and precancerous ( P  = 0.0049) groups was observed. A time-dependent increase in p-Akt in the NHBE, NHOK, HaCaT and OEC-M1 cell lines was observed with 100 μM nicotine treatment. The dose-dependent increase in p-Akt by nicotine treatment in HaCaT and OEC-M1 cells was obviously observed. Higher p-Akt expression in more alkaline environment (pH 8.0) was observed than at pH 7.4 in OEC-M1 cells.
Conclusion:  A potential role for increased p-Akt may relate to the dose and time of nicotine use. The potential role of an alkaline environment to enhance nicotine-related oral carcinogenesis may exist.     

Depigmentation of oral mucosa as the earliest possible manifestation of oral submucous fibrosis in Sri Lankan preschool children

This article reports the presentation of oral submucous fibrosis in five Sri Lankan preschool children, aged 2–3 years, with loss of pigmentation of the lips as the sole clinical feature. Oral submucous fibrosis has not been reported in this age group of children. The five 2–3 year olds did not display any classical features of oral submucous fibrosis, due to the disease having been detected at a very early stage. The present study attempts to establish that depigmentation of the lips and oral mucosa is perhaps the earliest feature to develop in the natural history of oral submucous fibrosis. The differential diagnosis of oral mucosal depigmentation relevant to these cases is also discussed. Previously‐reported cases of oral submucous fibrosis in children are reviewed.     

民族药儿茶的生药学鉴定

目的 对多民族常用的植物药儿茶进行生药学鉴定,为其鉴别及应用提供科学依据.方法 采用原植物、性状、显微和薄层鉴别的方法 .结果 儿茶在原植物、性状、显微和薄层等方面具有专属性的特征.结论 通过原植物、性状、显微鉴别和薄层能够很好地鉴定该药材.