Genotoxic and tumorigenic pyrrolizidine alkaloids in Chinese herbal plants

Pyrrolizidine alkaloids are a class of hepatotoxic and tumorigenic compounds detected in Chinese herbal plants, contaminated foods, and dietary supplements. In this review, the sources, toxicity, genotoxicity, tumorigenicity, and the metabolic pathways,particular the activation pathways leading to hepatotoxicity and tumorigenicity, of pyrrolizidine alkaloids are briefly discussed, with a focus on the most recent important findings concerning the genotoxic mechanism by which riddelliine liver tumors. This mechanism involves the formation of 6,7-dihydro-7-hydroxy-1-hydroxymethy1-5H-pyrrolizine (DHP)-derived DNA adducts and may be general to most carcinogenic pyrrolizidine alkaloids.     

吡咯里西啶生物碱的细胞毒性及致毒机制研究进展

吡咯里西啶生物碱广泛分布于6 000多种高等植物中，是一类肝毒性很强的天然产物。吡咯里西啶生物碱在肝脏代谢成活性代谢物吡咯后产生肝毒性。利用体外细胞毒性研究方法评价吡咯里西啶生物碱的毒性，对于阐明吡咯里西啶生物碱的致毒机制，研究开发拮抗其毒性的药物及保证临床用药安全具有重要意义。本文对吡咯里西啶生物碱的细胞毒性及致毒机制的研究进展进行综述。     

Comfrey: assessing the low-dose health risk

The regular use of comfrey as part of the diet or for medicinal purposes may be a potential health risk as a result of the presence of naturally-occurring pyrrolizidine alkaloids. The majority of these alkaloids are hepatotoxic in both animals and humans, and some have been shown to induce tumours in experimental animals. In this article, the toxic properties of pyrrolizidine alkaloids are reviewed briefly, with particular reference to their presence in comfrey. The acute and long-term health risks at the normally-low levels of comfrey consumption are evaluated and discussed. On the basis of the data that are available currently, the small but significant long-term risk that is associated with the consumption of comfrey justifies the need to limit its intake. This is being achieved by controls under various state Poisons Acts, but also requires further education on the potential dangers of naturally-occurring chemicals of plant origin.     

Plant profile,phytochemistry and pharmacology of Cordia dichotoma (Indian cherry): A review

More than half of the world''s population relies on the traditional medicine and major role of the traditional medicine including the use of plant extract and their active constituents. Among them, Cordia dichotoma Forst., a small to moderate size plant of family Boragenaceae, commonly called bhokar, lasura, gonda, Indian cherry and shlesmataka. Plant parts such as leaves, fruit, bark and seed have been reported for possessing antidiabetic, antiulcer, anti-inflammatory, immune-modulator and analgesic activity. Screening of fruit, leaves and seed shows the presence of pyrrolizidine alkaloids, coumarins, flavonoids, saponins, terpenes and sterols. Present review focuses on details of geographical distribution, physicochemical parameters, phytoconstituents and pharmacological properties of Cordia dichotoma reported so far.     

液质联用技术在乌头类生物碱定性定量研究中的应用

为了更好地控制乌头类生物碱的药品质量,阐明该类成分在体内的代谢转化及药动学特征,综述了液质联用技术在乌头类生物碱的裂解、成分鉴别、炮制配伍前后成分变化、药物的体内代谢转化、药物代谢动力学及药材、饮片、成药质量控制等方面的应用。     

THH碱不通过钙离子信号通道诱导Jurkat淋巴瘤细胞株凋亡

目的 探讨昆明山海棠碱在凋亡中对细胞内游离钙离子浓度的影响。方法 THH碱诱导Jurkat细胞后，采用Indo-1 AM及PI进行细胞染色、流式细胞术等手段在单细胞水平上检测细胞内钙离子浓度的变化。结果 THH碱诱导后细胞内钙离子浓度未见明显变化。结论 THH碱不通过钙离子信号通道诱导Jurkat细胞凋亡。     

乳腺癌干细胞分离及异质性的研究进展

乳腺癌干细胞是来源于乳腺干细胞或乳腺上皮细胞祖细胞的具有自我更新能力、致瘤性和分化能力等特性的乳腺癌细胞,其表面抗原预示了乳腺癌干细胞的异质性。同时,不同信号调节通路在乳腺癌调节作用中的研究进一步表明乳腺癌干细胞的异质性。现针对近年来乳腺癌干细胞分离研究中其表面标记分子的演化及异质性表现进行分析,从而为开展相关研究提供参考。     

基于网络药理学酸枣仁生物碱抗抑郁作用机制的研究

目的:采用网络药理学方法预测酸枣仁生物碱抗抑郁的作用机制。方法:首先挖掘相关的数据库如TCMSP、TCMDatabase@Taiwan、Drug Bank、Pharm Mapper、DAVID等,获得酸枣仁生物碱的主要成分和生物碱抗抑郁的潜在作用靶点,并对潜在靶点进行KEGG通路和GO分析。进一步采用软件Cytoscape构建并分析“成分-靶点-通路”生物网络图,最终从整体角度预测酸枣仁生物碱抗抑郁的作用机制。结果:酸枣仁生物碱抗抑郁的主要成分包括荷叶碱（nuciferine）、原荷叶碱（nornuciferine）、右旋衡州乌药碱（coclaurine）、木兰花碱（magnoflorine）,主要作用于钙调蛋白（CALM1）、表皮生长因子受体（EGFR）、糖原合成酶激酶-3β（GSK3B）、视黄酸受体（RXRA）等靶点,涉及并影响磷脂酰肌醇3激酶-蛋白激酶B（PI3K-Akt）、钙离子等信号通路以及丝裂原活化蛋白激酶（MAPK）级联、蛋白结合等生物进程,发挥抗抑郁作用。结论:初步预测获得酸枣仁生物碱抗抑郁作用机制,多成分-多靶点-多通路的特点符合中医整体综合作用理念。     

IL—2和IL—3基因共转染白血病细胞的体内外生物学特性

目的：研究细胞介素２（ＩＬ－２）、白细胞介素３（ＩＬ－３）基因共转染瘤苗的体现人外生物学特性。方法：用ＩＬ－２重组腺病毒（Ａｄ－ＩＬ－２）、ＩＬ－３重组腺病毒（Ａｄ－ＩＬ－３）转染ＦＢＬ－３红白血病细胞株，观察其体外增殖能力及体内致瘤性的变化。结果：ＩＬ－１、ＩＬ－３共转染的ＦＢＬ－３细胞１周内能较稳定地分泌ＩＬ－２和ＩＬ－３，体外增殖能力无明显变化，但体内致瘤性明显下降，ＩＬ－２、ＩＬ－３共转染     

Safety Issues of Chinese Medicine: A Review of Intoxication Cases in Hong Kong

中药在香港的应用已有几个世纪的历史。实际上,大约60%的香港人使用中药。然而,近年来,关于中药中毒致死的报道越来越多。误用有毒的或具有潜在毒性的中药可以导致严重的中毒反应。从该角度出发,本文综述了发生在香港的中药中毒事件,对中药的毒性和副作用以及质量控制也给出了深入的见解。通过提高对中药毒性的认知,可以更好地研究中药毒性成分、机理及质量控制。