白族草药紫金龙成分的研究

从白族草药紫金龙根中分离得到 3种生物碱 ,通过 UV,IR,MS等方法解析 ,鉴定其结构 ,确定为普罗托品、右旋异紫堇丁和右旋紫堇丁 ,其中普罗托品盐酸盐为生药的 1 .1 %。     

异紫堇定的扩血管作用与环核苷酸的关系(英文)

应用血管平滑肌等张收缩和放射免疫测定环核苷酸水平等方法研究了异紫堇定扩血管作用及其机理 .结果表明 ,异紫堇定浓度依赖性地松弛去甲肾上腺素 (NE ,1μmol·L- 1)和KCl(30mmol·L- 1)预收缩的兔胸主动脉螺旋条 ,EC50 分别为 (12 .6± 4 .4 )和 (447± 38) μmol·L- 1,对NE的作用比对KCl强 36倍 .亚甲蓝 (10 μmol·L- 1)可部分抑制异紫堇定的扩血管作用 ,但不受格列本脲 ,吲哚美辛 ,普萘洛尔或N L 硝基精氨酸影响 .异紫堇定还可促进cGMP生成增加 ,并可被亚甲蓝完全阻断 .异紫堇定对cAMP的生成无影响 .结果提示 ,异紫堇定的扩血管作用至少部分通过激活鸟苷酸环化酶 ,促进cGMP的生成实现     

异紫堇啡碱对血管平滑肌钙内流和钙释放的影响

目的研究异紫堇啡碱（ＩＳＯＣ）对血管平滑肌钙内流和钙释放的影响，以初步阐明其作用方式。方法利用兔胸主动脉螺旋条标本观察ＩＳＯＣ对去甲肾上腺素（ＮＡ）及ＫＣｌ量效曲线的影响和对无钙液中ＮＡ、ＣａＣｌ２复钙、咖啡因缩血管效应的影响。结果ＩＳＯＣ１０μｍｏｌ·Ｌ－１对ＮＡ的量效曲线呈非竞争性拮抗作用，而对高钾的作用则不明显。在无钙液中，ＩＳＯＣ１００μｍｏｌ·Ｌ－１能明显抑制ＮＡ所致的收缩及复钙后外钙内流诱发的收缩，ＩＳＯＣ１０及３０μｍｏｌ·Ｌ－１则只作用于前者；各实验浓度的ＩＳＯＣ对咖啡因在无钙液中的缩血管作用均无影响。结论ＩＳＯＣ抑制受体中介的钙释放和钙内流，但不是典型的钙拮抗剂。     

异紫堇碱及其类似物的抗癌活性研究

采用天然产物化学研究手段,从秃疮花和云南地不容中分离得到部分异紫堇碱类生物碱,并对异紫堇碱进行化学结构修饰得到异紫堇碱类似物,采用MTT法考察了异紫堇碱类似物对3种人癌细胞株的细胞生长抑制活性。结果表明异紫堇碱及其类似物均具有一定的抗癌活性,结合异紫堇碱及其类似物的单晶衍射结构与EGFR分子对接模拟,从立体化学结构、化合物不同取代基位置以及芳香环电子云密度等角度探讨了该类化合物具有抗癌活性的构效关系。     

异紫堇碱抑制裸鼠人宫颈癌Siha细胞移植瘤的生长

目的研究异紫堇碱(ICD)对裸鼠人宫颈癌Siha细胞移植瘤的影响,探讨异紫堇碱抑制宫颈癌发生发展的机制。方法将人宫颈癌Siha细胞接种于BALB/c(nu/nu)裸鼠皮下建立动物模型,待移植瘤平均直径≥0.5 cm时,随机分为对照组及腹腔注射不同剂量异紫堇碱干预组。4周后取出瘤体组织,用HE染色法观察瘤体组织病理形态学,用免疫组化染色及Western blot方法观察负荷瘤组织中的蛋白表达。结果经异紫堇碱干预后的宫颈癌Siha细胞裸鼠负荷瘤体积减小(P<0.05);细胞形态可由干细胞样向上皮样细胞转化;上皮细胞分化成熟标记E-cadherin表达明显升高,而HPV16E6蛋白和间叶组织标志物vimentin的表达下降。结论异紫堇碱可能通过抑制携带HPV亚型的宫颈癌Siha细胞中E6蛋白的表达及EMT相关信号通路来抑制宫颈癌的发生发展。     

天然产物异紫堇二酮的半合成转化研究

通过紫外分光光度法,以异紫堇二酮的半合成转化产率为指标,详细考察反应时间、反应温度和投料比(异紫堇碱∶弗瑞米自由基)对转化产率的影响,确定异紫堇二酮的最佳合成条件:pH值为10的磷酸氢二钠溶液为反应介质、反应温度25℃、投料比(异紫堇碱∶弗瑞米自由基)=1∶2,反应时间12 h,通过氧化异紫堇碱可以半合成转化制备异紫堇二酮,产率可达到50.0%,并首次通过X-ray单晶衍射测定异紫堇二酮的化学结构。     

Ethnobotany,phytochemistry and pharmacology of Stephania rotunda Lour

Ethnopharmacological relevance

Stephania rotunda Lour. (Menispermaceae) is an important traditional medicinal plant that is grown in Southeast Asia. The stems, leaves, and tubers have been used in the Cambodian, Lao, Indian and Vietnamese folk medicine systems for years to treat a wide range of ailments, including asthma, headache, fever, and diarrhoea. Aim of the review: To provide an up-to-date, comprehensive overview and analysis of the ethnobotany, phytochemistry, and pharmacology of Stephania rotunda for its potential benefits in human health, as well as to assess the scientific evidence of traditional use and provide a basis for future research directions.

Material and methods

Peer-reviewed articles on Stephania rotunda were acquired via an electronic search of the major scientific databases (Pubmed, Google Scholar, and ScienceDirect). Data were collected from scientific journals, theses, and books.

Results

The traditional uses of Stephania rotunda were recorded in countries throughout Southeast Asia (Cambodia, Vietnam, Laos, and India). Different parts of Stephania rotunda were used in traditional medicine to treat about twenty health disorders. Phytochemical analyses identified forty alkaloids. The roots primarily contain l-tetrahydropalmatine (l-THP), whereas the tubers contain cepharanthine and xylopinine. Furthermore, the chemical composition differs from one region to another and according to the harvest period. The alkaloids exhibited approximately ten different pharmacological activities. The main pharmacological activities of Stephania rotunda alkaloids are antiplasmodial, anticancer, and immunomodulatory effects. Sinomenine, cepharanthine, and l-stepholidine are the most promising components and have been tested in humans. The pharmacokinetic parameters have been studied for seven compounds, including the three most promising compounds. The toxicity has been evaluated for liriodenine, roemerine, cycleanine, l-tetrahydropalmatine, and oxostephanine.

Conclusion

Stephania rotunda is traditionally used for the treatment of a wide range of ailments. Pharmacological investigations have validated different uses of Stephania rotunda in folk medicine. The present review highlights the three most promising compounds of Stephania rotunda, which could constitute potential leads in various medicinal fields, including malaria and cancer.     

An isocorydine derivative (d-ICD) inhibits drug resistance by downregulating IGF2BP3 expression in hepatocellular carcinoma

In our previous studies, we reported that CD133⁺ cancer stem cells (CSCs) were chemoresistant in hepatocellular carcinoma (HCC) and that isocorydine treatment decreased the percentage of CD133⁺ CSCs. Here, we found that a derivative of isocorydine (d-ICD) inhibited HCC cell growth, particularly among the CD133⁺ subpopulation, and rendered HCC cells more sensitive to sorafenib treatment. d-ICD inhibited IGF2BP3 expression in a time-dependent manner, and IGF2BP3 expression negatively correlated with d-ICD-induced growth suppression. IGF2BP3 overexpression enriched the CD133⁺ CSC subpopulation in HCC, enhanced tumor sphere formation and suppressed the cytotoxic effects of sorafenib and doxorubicin. The expression of drug resistance-related genes, including ABCB1 and ABCG2, and the CSC marker CD133 expression was increased after IGF2BP3 overexpression. The significance of these observations was underscored by our findings that high IGF2BP3 expression predicted poor survival in a cohort of 236 patients with HCC and positively correlated with ABCG2 and CD133 expression in vivo. These results suggested that the d-ICD may inhibit HCC cells growth by IGF2BP3 decrease and that IGF2BP3 may serve as a therapeutic target for HCC.     

RP-HPLC同时测定紫金龙中4种异喹啉生物碱的含量

 目的建立同时测定紫金龙药材4种异喹啉类生物碱含量的RP-HPLC方法。方法采用Hypersil BDS C₁₈色谱柱(4.6mm×250mm,5μm),流动相为梯度洗脱,A相:0.2%磷酸水溶液(三乙胺调pH为7.0),B相:甲醇;流速:1mL·min^-1;检测波长:265nm;柱温:30℃。结果4种生物碱可达到基线分离。青藤碱、原阿片碱、紫堇定和异紫堇定的线性范围分别为0.0073～0.0657μg,0.1722～4.304μg,0.486～4.86μg和0.4870～9.7392μg,相关系数r均大于0.9990。平均加样回收率分别为97.84%(RSD=0.89%)、98.98%(RSD=0.58%)、97.14%(RSD=1.13%)和97.65%(RSD=0.74%)。结论本法精确、简便、重现性好,可用于对紫金龙药材及其制剂的质量控制。     

异紫堇定的扩血管作用与环核苷酸的关系

应用血管平滑肌等张收缩和放射免疫测定环核苷酸水平等方法研究了异紫堇定扩血管作用及其机理. 结果表明,异紫堇定浓度依赖性地松弛去甲肾上腺素（NE, 1 μmol·L^-1）和KCl（30 mmol·L^-1）预收缩的兔胸主动脉螺旋条, EC₅₀分别为（12.6±4.4）和（447±38）μmol·L^-1,对NE的作用比对KCl强36倍. 亚甲蓝(10 μmol·L^-1)可部分抑制异紫堇定的扩血管作用,但不受格列本脲,吲哚美辛,普萘洛尔或N-L-硝基精氨酸影响. 异紫堇定还可促进GMP生成增加,并可被亚甲蓝完全阻断. 异紫堇定对cAMP的生成无影响. 结果提示,异紫堇定的扩血管作用至少部分通过激活鸟苷酸环化酶,促进cGMP的生成实现.