载蟾毒灵聚氰基丙烯酸正丁酯纳米粒的制备及其评价

目的以聚氰基丙烯酸正丁酯(PBCA)纳米粒为载体,制备包载中药单体蟾毒灵的纳米粒制剂。方法采用醇中聚合法制备了包载蟾毒灵的PBCA纳米粒,通过单因素试验及正交试验设计对制备工艺进行考察,并测定了纳米粒的粒径分布、形态、包封率、载药量及溶血性等理化性质。结果醇中聚合法制备的蟾毒灵PBCA纳米粒形态均匀,平均粒径为(151.2-6.1)nm,多分散系数为0.133±0.024,Zeta电位为(-7.09±0.58)mV,包封率为(70.812±6.139)%,载药量为(1.990±0.291)%;与蟾毒灵原料药相比,该制剂的溶血性更低,安全性有所提高。结论蟾毒灵PBCA纳米粒的制备方法,可有效缩短中药单体与酸性介质的接触时间,制得的纳米粒各项理化性质良好,可为易水解中药单体纳米粒载体的制备提供新思路。     

蟾酥的镇痛活性成分

药效学实验结果表明：蟾酥镇痛的活性成分主要存在于氯仿提取物中．分离蟾酥的氯仿提取物得到了脂蟾毒配基等６种单体化合物．６种单体化合物均具有一定的镇痛作用．华蟾毒精和脂蟾毒配基有非常显著的镇痛作用；蟾毒灵镇痛作用较平稳；南美蟾毒精镇痛作用较弱     

Anti-tumor effect of bufalin on the orthotopic transplantation tumor model of human hepatocellular carcinoma in nude mice

Objective: To investigate anti-tumor effect of bufalin on the orthotopic transplantation tumor model of human hepatocellular carcinoma in nude mice. Methods: BEL-7402 cells of human hepatocellular carcinoma were inoculated to form subcutaneous tumors in nude mice by subcutaneous injection. Then the subcutaneous tumors were implanted into the liver of nude mice, and the orthotopic transplantation tumor models of human hepatocellular carcinoma were established. Seventy-five models were randomized into 5 groups ( n = 15) . Bufalin was injected intraperitoneally into the 3 groups at dose of 1.5,1 and 0.5 mg/kg for day 15 - 24, respectively. NS group were injected equal volume saline as above and adriamycin were injected intraperitoneally into ADM group at dose of 8.0 mg/kg for day 15. Ten mice in each group were killed at day 25 and detected on morphological and ultrastructural changes in myocardium, brain, liver, kidney and tumor tissues by pathology and electron microscope. The survival time in each group     

蟾毒灵抑制人结肠癌HCT116细胞侵袭机制探讨

目的 肿瘤侵袭转移的发生是影响结肠癌治疗的重要原因,结肠癌细胞黏附能力的下降以及迁移能力的增强是促进结肠癌细胞侵袭转移的重要原因.有研究发现,蟾毒灵具有抑制结肠癌细胞侵袭能力的作用,但其作用机制尚不明确.本研究探讨蟾毒灵对人结肠癌HCT116细胞侵袭的影响,并探索其可能的作用机制.方法 用蟾毒灵溶液干预结肠癌HCT116细胞,采用细胞划痕实验与细胞黏附实验检测蟾毒灵溶液对结肠癌HCT116细胞侵袭能力的影响;ELISA法检测蟾毒灵溶液干预结肠癌HCT116细胞培养基中细胞外泌TGFβ1蛋白的含量;蛋白质印迹法检测蟾毒灵干预后结肠癌HCT116细胞中P-smad3、smad4和钙黏链蛋白(E-cadherin)表达的变化;免疫荧光实验检测蟾毒灵干预后各组HCT116细胞中P-smad3与smad4蛋白表达的变化.结果 细胞划痕实验结果显示,低、中、高剂量蟾毒灵均可降低HCT116细胞迁移能力;细胞黏附实验显示,对照组、低剂量组、中剂量组和高剂量组黏附细胞平均值分别为833.33±7.80、877.00±17.75、1 304.00±15.82和1 406.00±20.53,相对黏附率分别为100％、105.24％、156.48％和168.73％,差异有统计学意义,x2 =297.597,P＜0.001.ELISA检测结果显示,对照组、低、中和高剂量细胞培养液中转化生长因子β(transforming growth factor-β,TGFβ1)蛋白含量分别为(1 198.78±38.96)、(1 106.58±35.76)、(1 040.80±47.47)和(987.74±37.52) pg/mL,F=16.357,P=0.005.蛋白质印迹法检测结果显示,与对照组相比,中、高剂量蟾毒灵处理后HCT116细胞中P-smad3表达呈现明显下降;而smad4蛋白表达明显上调,组间差异有统计学意义,F=56.993,P＜0.001;低剂量蟾毒灵也可上调smad4蛋白的表达,t=5.342,P=0.006.各用药组HCT116细胞中E-cadherin蛋白的表达水平也随着蟾毒灵剂量的增加而增加,分别为对照组的2.514±0.385(t=4.833,P=0.008)、3.524±0.397(t=9.200,P=0.001)和3.937±0.318(t=10.675,P＜0.001)倍;免疫荧光法检测发现,蟾毒灵处理后结肠癌HCT116细胞中P-smad3与smad4蛋白的表达呈现出与蛋白质印迹法检测相似的趋势.结论 蟾毒灵可通过抑制TGFβ1/smad信号通路的信号传导抑制结肠癌HCT116细胞的侵袭.     

Ouabain attenuates cardiotoxicity induced by other cardiac steroids

Background and purpose:

All cardiac steroids have a similar structure, bind to and inhibit the ubiquitous transmembrane protein Na⁺, K⁺-ATPase and increase the force of contraction of heart muscle. However, there are diverse biological responses to different cardiac steroids both at the cellular and at the molecular level. Moreover, we have recently shown that ouabain inhibits digoxin- and bufalin-induced changes in membrane traffic. The present study was designed to test the hypothesis that ouabain also has an inhibitory effect on cardiotoxicity induced by other cardiac steroids.

Experimental approach:

The hypothesis was tested in isolated heart muscle preparations and in an in vivo model of cardiotoxicity in guinea pigs.

Key results:

Ouabain at a low dose attenuated the toxicity induced by bufalin and digoxin in heart muscle preparations. In addition, ouabain at the low dose (91 ng·kg⁻¹·h⁻¹), but not at a higher dose (182 ng·kg⁻¹·h⁻¹), delayed the development of digoxin-induced (500 µg·kg⁻¹·h⁻¹) cardiotoxicity in anaesthetized guinea pigs, as manifested by delayed arrhythmia and terminal ventricular fibrillation, as well as a reduced heart rate. In addition, as observed with ouabain, the phosphoinositide 3-kinase inhibitor wortmannin (100 µg·kg⁻¹·h⁻¹) delayed the digoxin-induced arrhythmia in anaesthetized guinea pigs.

Conclusions and implications:

The present study demonstrates the inhibitory effect, probably through signal transduction pathways, of ouabain on digoxin- and bufalin-induced cardiotoxicity in guinea pigs. Further understanding of this phenomenon could be beneficial for increasing the therapeutic window for cardiac steroids in the treatment of chronic heart failure.     

蟾酥中3种蟾毒配基组合物的表观溶解度和表观油水分配系数的测定

目的：测定蟾酥中3种蟾毒配基组合物的表观溶解度和表观油水分配系数。方法：采用高效液相色谱法测定了蟾酥中3种蟾毒配基组合物中RBG，CBG，BL的表观溶解度，采用摇瓶法测定了RBG，CBG，BL的表观油水分配系数。结果：37 ℃，pH 7.0时，蟾酥中3种蟾毒配基组合物中RBG，CBG，BL的表观溶解度均为最大值，分别是76.29，51.85，32.76 μg·mL^-1，总溶解度为160.9 μg·mL^-1。在偏酸和偏碱性条件下，三者均有不同程度的降解。RBG，CBG，BL在不同pH条件下各自log P值差别不大，pH对RBG，CBG，BL的油水分配系数影响不显著，三者的油水分配系数均较大，为典型的疏水性产物，三者的疏水性大小顺序为RBG>BL>CBG。结论：蟾酥中3种蟾毒配基组合物中RBG，CBG，BL的水溶性差，疏水性极强，应考虑加入表面活性剂增溶，以利于注射制剂的成型。     

蟾蜍灵对肝癌细胞SMMC 7721的细胞毒作用及生长相关基因表达的影响

为探讨蟾蜍灵的抗癌作用机理 ,以肝癌SMMC772 1细胞为靶细胞 ,应用噻唑蓝还原法检测细胞毒作用 ,双荧光染色法和DNA电泳技术检测细胞凋亡与坏死 ;免疫组织化学方法检测细胞生长相关基因p2 1waf1/cip1和增殖细胞核抗原 (PCNA)蛋白表达 .结果表明 ,0 .0 1μmol·L- 1及以上浓度蟾蜍灵对SMMC772 1细胞具有显著细胞毒作用 ,形态学和DNA片段化检测证实蟾蜍灵诱导的细胞死亡以凋亡为主 ;p2 1waf1/cip1在蟾蜍灵诱导下表达上调 ,同时PCNA的表达下降 ,两者呈负相关 (P <0 .0 1) .提示蟾蜍灵通过上调p2 1waf1/cip1表达 ,下调PCNA表达 ,从而抑制肝癌细胞生长     

布法灵体外透皮试验

目的：以蟾酥灵定量分析布法灵对皮肤的通透性及透皮吸收规律。方法：用紫外分光光度法测定了布法灵的透皮吸收量和吸收率。结果：布法灵体外皮肤吸收速度与浓度和时间之间均有依赖关系;吸收速度随时间的延长而由快变慢、高浓度大于低浓度。结论：布法灵外涂给药能通透皮肤屏障,从而发挥镇痛作用。     

蟾蜍灵诱导人胃癌SGC7901细胞自噬与凋亡的研究

目的：探讨自噬在蟾蜍灵（bufalin）诱导人胃癌SGC7901细胞死亡中的作用.方法：不同浓度的bu-falin处理人胃癌SGC7901细胞,采用MTT法检测bufalin对SGC7901细胞增殖的抑制作用.透射电镜观察给药后SGC7901细胞的自噬现象;流式细胞术检测细胞凋亡.Western blot检测自噬标志LC3蛋白表达.结果：Bufalin对胃癌SGC7901细胞生长有显著的抑制作用,且此作用呈明显的时间-剂量依赖性.Bufalin给药后可诱导SGC7901细胞发生自噬;并且在bufalin给药前用氯喹阻断自噬明显提高了bufalin对SGC7901的细胞毒性（P＜0.05）.结论：Bufalin能明显抑制SGC7901细胞的生长,并且诱导其发生保护性自噬.Bufalin和自噬抑制剂的联合应用可能为胃癌治疗提供新的策略.     

HPLC法同时测定不同产地蟾酥中的5种活性成分

目的 建立了同时测定蟾酥中活性成分的HPLC方法,并对5个不同产地的药材中5种活性成分进行测定.方法 采用HPLC法测定,色谱柱为Hypersil ODS柱(250 mm×4.6 mm,25 μm),流动相为醇-水(50∶50),检测波长296 nm,柱温30℃,体积流量1 mL/min,并在此色谱条件下测定不同产地经60％甲醇回流提取的蟾酥样品中活性成分的量.结果 各成分的质量浓度和峰面积具有良好的线性关系,且有很好的分离度.日蟾毒它灵、蟾毒灵、沙毒精、华蟾酥毒基、脂蟾毒配基平均回收率为99.9％、99.6％、97.9％、96.7％、99.5％,RSD为2.8％、3.2％、1.9％、1.0％、3.4％.不同产地蟾酥样品的HPLC色谱图差别明显,所含成分的种类和质量分数差异较大.结论 本方法简便、灵敏度高,具有实用性,可作为蟾酥药材的质量控制方法.