阿霉素心脏毒性中脂质过氧化的研究

阿霉素细胞毒性的机制尚不完全清楚,其心脏毒性中自由基的机制颇受重视。阿霉素产生的氧自由基引起细胞损伤,如使不饱和脂肪酸过氧化,产生过氧化脂质(LPO)。阿霉素静注的大鼠血清及心肌LPO升高,用活性氧基的清除剂超氧物歧化酶、过氧化氢酶、二甲基亚砜治疗阿霉素处理的大鼠,可见LPO减少,心脏病理变化也有所减轻。说明阿霉素产生的氧自由基在其心脏毒性的发生中起重要作用。     

预先给予粉防已碱对大鼠工作心脏缺血再灌注损伤的…

预给粉防已碱１５ｍｇ．ｋｇ＾－１每日２次连续３ｄ可以减轻大鼠工作心脏缺血再灌注心肌损伤；促进冠脉流出液，心输出量的恢复；防止左心室舒张末期压和等容舒张期左室内压下降时间常数的升高；抑制肌酸激敏释放；维持心肌线粒体Ｃａ＾２＋稳态，以上结果与硝苯地平类似，本研究表明粉防已碱对心肌缺血再灌注损佃具有较好的保护作用，以对心肌舒张功能及冠脉循环的保护为优。     

磷酸肌酸钠对阿霉素所致心肌损伤大鼠急性期心肌组织连接蛋白43表达的影响

目的探讨磷酸肌酸钠对阿霉素所致心肌炎大鼠急性期心肌组织连接蛋白43(Cx43)表达的影响,探讨磷酸肌酸钠对阿霉素所致心肌炎并发心律失常发挥作用的机制。方法 60只雄性SD大鼠分为磷酸肌酸钠干预组,阿霉素组和正常对照组,观察大鼠的一般情况,第14天无痛苦处死全部大鼠并留取心脏。免疫组织化学法检测Cx43蛋白水平表达,并进行定量分析。结果①阿霉素组大鼠心室肌组织炎症病灶中变性、坏死周围心肌细胞Cx43表达明显减弱,甚至阴性,分布不规则,Cx43蛋白表达明显低于对照组,差异有统计学意义(P<0.01)。②磷酸肌酸钠组Cx43蛋白表达明显高于模型组,差异有统计学意义(P<0.01)。结论阿霉素所致心肌损伤大鼠急性期心肌组织Cx43蛋白表达下降。磷酸肌酸钠能明显提高CVB心肌炎大鼠急性期心肌组织Cx43蛋白表达。     

参附注射液对大鼠慢性心力衰竭的保护作用研究

目的探讨参附注射液对阿霉素致大鼠慢性心力衰竭心脏功能的保护作用。方法腹腔注射阿霉素构建大鼠慢性心力衰竭模型,检测参附注射液静脉给药4周后动物心功能参数、心脏系数、血清脑钠肽(BNP)含量变化以及比较心室肌组织病理学改变。结果参附注射液可明显改善慢性心力衰竭模型大鼠的心脏系数和心室肌组织病理学形态,增加心率(HR)、左心室收缩压(LVSP)、左心室内压力上升最大速度(+dp/dt_(max))及左心室内压力下降最大速度(-dp/dt_(max)),降低左心室舒张末压(LVEDP)及血清BNP含量。结论参附注射液对阿霉素诱导的慢性心力衰竭具有明显保护作用。     

罗格列酮对阿霉素肾病大鼠足细胞nephrin表达的影响

目的建立阿霉素肾病模型,探讨罗格列酮对阿霉素肾病大鼠足细胞nephrin的表达的影响。方法21只大鼠随机分为3组。阿霉素肾病组和罗格列酮组大鼠予0.1%阿霉素溶液7 mg·kg~(-1)一次性尾静脉注射,罗格列酮组次日予罗格列酮5 mg·kg~(-1)·d~(-1)灌胃,每日1次,共8 wk。另外2组每日予等量自来水灌胃。检测各组大鼠24 h尿蛋白定量、血清清蛋白、血脂、肾功能及肾脏病理改变,并检测肾组织nephrin和TCFβ_1的表达。结果给药后2、4、6、8 wk,罗格列酮组大鼠24 h尿蛋白定量明显低于阿霉素肾病组(P<0.05),8 wk时其血清清蛋白高于阿霉素肾病组[(26.7±s 2.6)g·L~(-1)vs(21±4)g·L~(-1),P<0.05],血三酰甘油和胆固醇水平低于阿霉素肾病组(P<0.05)。与阿霉素肾病组比较,罗格列酮组大鼠肾组织中nephrin蛋白表达增高19%(P<0.05),而TGFβ_1蛋白表达明显降低(P<0.01),肾脏病理损害也明显减轻。结论罗格列酮可上调阿霉素肾病大鼠肾组织nephrin表达,减少尿蛋白排泄,抑制其TGFβ_1表达,从而减轻肾组织病理损害。     

粉防已碱对炎症白细胞磷脂酶A2的作用及其机理探讨

给大鼠胸膜腔内注射角叉菜胶（１０ｍｇ．ｋｇ＾－１）复制胸膜炎。粉防已碱（１０－８０ｍｇ．ｋｇ＾－１）于致炎前３０ｍｉｎ和致炎后４ｈ两次给大鼠ｉｇ能明显抑制炎症白细胞磷脂酶Ａ２（ＰＬＡ２）和钙调素活性并降低胞浆内游离钙浓度；在体外，粉防已碱与白细胞悬液孵育３０ｍｉｎ亦能明显抑制炎症白细胞ＰＬＡ２活性，这种作用可被Ｃａ＾２＋和钙调素提取液逆转。提示粉防已碱降低炎症白细胞ＰＬＡ２活性的作用与其拮抗Ｃａ＾     

全反式维甲酸对阿霉素肾病大鼠足细胞的保护作用

目的 探讨全反式维甲酸(ATRA)对阿霉素肾病大鼠足细胞是否具有保护作用.方法 通过建立阿霉素肾病大鼠模型,随机分为三组,即对照组、模型组、治疗组,于阿霉素注射后第2天治疗组每天给予20 mg/kg ATRA灌胃,每周检测24-h尿蛋白定量,4周后处死大鼠,检测血清白蛋白、胆固醇、甘油三酯、血肌苷、尿素氮、nephrin的表达.结果 治疗组与模型组相比大鼠尿蛋白明显减少(P<0.01).治疗组nephrin蛋白和mRNA含量均较模型组有所增加(P<0.05).结论 ATRA对阿霉素肾病大鼠足细胞有保护作用,其机制部分与nephrin的表达改变有关.     

大鼠心脏移植中常山酮对树突状细胞的抑制作用及对血清IL-17的影响

目的：观察大鼠移植心脏中常山酮( halofuginone, HF)对树突状细胞( dendritic cell, DC)的抑制作用及对IL-17的影响。方法将30只Wistar大鼠和30只SD大鼠分别随机分为HF-DC组、DC组和对照组,供体为Wistar大鼠,受体为SD大鼠。各组在术前及术后1 d对应注射经HF处理过的DC溶液、经生理盐水处理过的DC溶液及生理盐水;观察大鼠心脏移植术后存活时间、移植心脏排斥反应病理学分级及受体大鼠血清中IL-17的含量。结果HF-DC组和对照组大鼠的存活时间均显著高于DC组(P<0．05),且HF-DC组大鼠的存活时间显著高于对照组(P<0．05)。术后第5天,HF-DC组大鼠未见明显的炎性细胞浸润和血管炎症出现,术后第7天可见少量散在的淋巴细胞浸润,分级为Ⅱ级。术后第5天,DC组大鼠移植心脏发生了广泛的炎性浸润,分级为ⅢB级;对照组有多灶性侵袭性淋巴细胞浸润或伴有心肌细胞损害,分级为ⅡA级。在各时间点,DC组和HF-DC组大鼠血清IL-17含量显著高于对照组(P<0．05);HF-DC组大鼠血清IL-17含量显著低于DC组(P<0．05)。结论经HF处理的DC诱导免疫排斥反应的能力下降,HF通过降低T细胞增殖能力抑制IL-17的表达。     

扩张型心肌病大鼠心肌α-actin和NF-кB的表达及其与心功能的关系

目的:观察扩张型心肌病(DCM)大鼠心肌骨骼肌型α-肌动蛋白(α-actin)和核因子-кB(NF-кB)的表达及其与心功能的关系。方法:通过腹腔注射阿霉素建立大鼠DCM模型。超声心动图测定左室射血分数(LVEF),RT-PCR检测心肌骨骼肌型α-actin mRNA表达,免疫组化方法检测心肌骨骼肌型α-actin和NF-кB蛋白的表达。结果:(1)与正常大鼠比较:DCM大鼠骨骼肌型α-actin mRNA及蛋白表达均上调(P<0.01);DCM大鼠NF-кB活性增强(P<0.01)。(2)DCM大鼠LVEF与骨骼肌型α-actin mRNA水平呈负相关(r=-0.596,P<0.05);NF-кB活性与LVEF呈负相关(r=-0.738,P<0.01)。结论:DCM大鼠心肌骨骼肌型α-actin表达上调作为心肌细胞肥大的标志,提示左室收缩功能恶化,心肌进行代偿。DCM大鼠心脏局部炎症反应活跃并损害心功能。     

β-胡萝卜素对阿霉素所致的大鼠心脏毒性的作用(英文)

目的:研究β-胡萝卜素减轻阿霉素所致的大鼠心脏毒性的作用及其机制,方法:应用光学显微镜技术观察心肌组织的病理变化,心肌MDA值用巴比妥酸法测定,SOD活性用邻苯三酚法测定,GSH-Px活性用DTNB法测定,运用顺磁共振(ESR)技术测定半醌自由基。结果:β-胡萝卜素10或30mg·kg~(-1)可明显减轻阿霉素引起的大鼠心肌损害,保护SOD,GSH-Px活性,对抗阿霉素引起的心肌MDA水平升高,体外实验表明,β-胡萝卜素可以清除阿霉素诱导产生的半醌自由基,在0.02,0.1,1.0mmol·L~(-1)三个浓度时的抑制率分别为47.7％,76.6％,85.2％。结论:β-胡萝卜可以减轻阿霉素引起的大鼠心肌损害,其机制与抗脂质过氧化和清除半醌自由基有关。     

粉防己碱在体内的代谢转化

粉防已碱有多种药理作用,近年我国又发现它可以防治矽肺。薄层层析及高压液相层析结果表明,粉防己碱进入大鼠及人体内,大部分以原形存在,少部分被转化,在大鼠的肝、肺、尿及人尿中,代谢产物可能有两个粉防己碱-N-2′-氧化物异构体和N-2′-去甲基粉防己碱。在两个粉防己碱-N-2′-氧化物中,其一前人已有报道,另一个为新化合物,根据核磁共振谱、质谱以及它能还原成粉防己碱,确定了其化学结构。本文给出了粉防己碱的气相层析及高压液相层析的实验条件。     

The plasma glucose lowering action of tetrandrine in streptozotocin-induced diabetic rats

The effect of tetrandrine, an active principle of Stephaniae tetrandrae, on the plasma glucose level in streptozotocin-induced diabetic rats (STZ-diabetic rats) was investigated. A single intravenous injection of tetrandrine decreased the plasma glucose in a dose-dependent manner in STZ-diabetic rats. Moreover, tetrandrine (1.0 mg x kg(-1)) significantly attenuated the rise in plasma glucose induced by the intravenous glucose challenge test in normal rats. A stimulatory effect of tetrandrine on glucose uptake was obtained in soleus muscles isolated from STZ-diabetic rats with a concentration-dependent manner from 0.01 to 10.0 micromol L(-1). The increase in glucose utilization by tetrandrine was further characterized using the enhancement of glycogen synthesis in the hepatocytes of STZ-diabetic rats. These results suggest that tetrandrine has the ability to enhance glucose utilization in peripheral tissue, resulting in the lowering of plasma glucose in diabetic rats lacking insulin.     

Pulmonary toxicity and metabolic activation of tetrandrine in CD-1 mice

Tetrandrine, a bisbenzylisoquinoline alkaloid, has demonstrated promising pharmacologic activities. The alkaloid has a great potential for clinical use, so a careful, thorough toxicity evaluation of the alkaloid is required. In the present study, 24 h acute toxicity of tetrandrine was evaluated in CD-1 mice. Single intraperitoneal doses of tetrandrine at 150 mg (0.24 mmol)/kg were found to cause alveolar hemorrhage and over 3-fold elevation of lactate dehydrogenase activity in bronchoalveolar lavage fluids. Ethidium-based staining showed loss of membrane integrity in significant numbers of cells in the lungs of the animals treated with the same doses of tetrandrine. As much as 60% reduction in cell viability was observed after 24 h of exposure to tetrandrine at 40 μM in human lung cell lines NL-20 and WI-38. Ketoconazole, an inhibitor of P450 3A, showed a protective effect on the pulmonary injury in mice given tetrandrine. A glutathione (GSH) conjugate derived from O-demethylated tetrandrine was detected in incubations of tetrandrine with NADPH- and GSH-supplemented human liver and mouse lung microsomes. The electrophilic metabolite trapped by GSH is considered to be a quinone methide derivative. The formation of the metabolite reactive to GSH was found to require the presence of NADPH. The coincubation of ketoconazole suppressed the generation of the GSH conjugate. Tetrandrine was incubated with a selection of recombinant human cytochrome P450 enzymes, and only P450s 3A4 and 3A5 were responsible for the production of the reactive metabolite. The results implicate a possible correlation between the formation of the quinone methide metabolite of tetrandrine and the pulmonary toxicity induced by tetrandrine.     

汉防己甲素聚乳酸微球小鼠肺靶向研究

目的 :研究汉防己甲素聚乳酸微球的肺靶向性。方法 :分别对小鼠尾静脉注射汉防己甲素聚乳酸微球和汉防己甲素注射剂 ,以反相高效液相色谱法测定并比较小鼠各组织中汉防己甲素的浓度。结果 :汉防己甲素在血浆中检测浓度范围为0 .519～17 000μg/ml(r=0. 9996) ,加样回收率为97 .32 % ,相对标准差平均值为4 .46 % ;应用汉防己甲素聚乳酸微球后汉防己甲素在小鼠各组织中浓度明显高于汉防己甲素注射剂 ;汉防己甲素在小鼠肺中浓度明显高于其它组织。结论 :汉防己甲素聚乳酸微球具有明显的肺靶向性。     

Effect of tetrandrine combined with epirubicin on the growth of human breast carcinoma multidrug resistance cell line

Multidrug resistance presents a serious problem in cancer chemotherapy. Recent studies have shown that the multidrug resistance of tumor cells can be reversed by tetrandrine by potentiating the cytotoxicity of chemotherapeutic agents. However, whether tetrandrine has such potentiating effect on epirubicin has not been reported. Thus, the combined effect of tetrandrine and epirubicin on the growth of human breast carcinoma multidrug-resistant MCF-7/ADM cells was studied in the present study. It was shown that tetrandrine significantly potentiated the cytotoxicity of epirubicin. To examine the mechanism of the combined effect of tetrandrine and epirubicin on MCF-7/ADM cell growth, cell cycle progression was evaluated by using flow cytometry. The combined use of tetrandrine and epirubicin caused an accumulation of cells at G(2)/M phase, accompanied with a concomitant decrement of cell number at G(0)/G(1) phase. The present study demonstrated for the first time that tetrandrine potentiated the cytotoxcity of epirubicin on MCF-7/ADM cells. Cell cycle arrest at G(2)/M phase may contribute to the combined effect of tetrandrine and epirubicin.     

粉防己碱和甲基莲心碱对大鼠离体胸主动脉环收缩的影响

以苯肾上腺素为激动剂,在无钙K-H液中诱发大鼠去内皮主动脉环收缩并随后复钙的方法,观察粉防已碱和甲基莲心碱对主动脉环Ⅰ相收缩(胞内Ca~(++)释放)和Ⅱ相收缩(胞外Ca~(++)内流)的效应。结果表明,2×10~(-5)mol/L粉防己碱或甲基莲心碱预孵20min后,对Ⅰ、Ⅱ相的收缩均有非常明显的抑制作用(抑制率>92%,P<0.001);而短时预孵(5～10min)两药仅对Ⅲ相收缩有抑制作用,甲基莲心碱比粉防己碱起效慢、作用弱。     

汉防己甲素及乙素对心血管系统的作用

1.以汉防已甲素或乙素3毫克/公斤靜脉注射、肌肉注射或灌胃,均可使麻醉猫的血压明显下降,甲素之降压作用較乙素大而持久,甲素靜脉注射时,降压作用急驟而持久,可維持1—5小时;肌肉注射及灌胃时,降压作用較緩慢,但亦甚持久。2.乙素之降压作用較甲素弱而短暫,靜脉給药之作用較肌肉注射为强,灌胃之降压作用又較肌肉注射为弱。3.静脉注射甲素或乙素3毫克/公斤,在血压下降的同时,可見暫时性心收縮力減弱;但肌肉注射同样或更大剂量(5毫克/公斤),則不出現心力抑制現象,甲素对心率之影响較少,乙素則往往引起心率減慢,心动电流圖上仅見R波幅度之減小,对P-R間歇及T波等均無影响。4.甲素及乙素可使脾容积增加,但在血压急剧下降时,則可使脾容积縮小。5.甲素及乙素均可使离体兎耳血管扩張,直接对平滑肌之抑制作用及神經反射机制均参加在內.甲素之血管扩張作用較乙素及罂粟硷为大而持久。     

粉防己碱对大鼠离体主动脉条45Ca内流的影响

本文研究了粉防己碱（Ｔｅｔｒａｄｒｉｎｅ，Ｔｅｔ）对大鼠离体胸主动脉条~（４５）Ｃａ内流的影响。结果表明，粉防己碱（３×１０~（－５）ｍｏｌ·Ｌ~（－１））与维拉帕米（Ｖｅｒａｐａｍｉｌ，浓度为１×１０~（－５）ｍｏｌ·Ｌ~（－１））相似，可以抑制高Ｋ~＋激发的主动脉条~（４５）Ｃａ的内流量，但不能阻断由苯肾上腺素（Ｐｈｅｎｙｌｅｐｈｒｉｎｅ，浓度为１×１０~（－５）ｍｏｌ·Ｌ~（－１））激发的~（４５）Ｃａ内流量。结果提示，粉防己碱可能是选择性地阻断电压操纵的钙通道而抑制~（４５）Ｃａ内流。     

Plant alkaloid tetrandrine downregulates protein kinase C-dependent signaling pathway in T cells

Tetrandrine, a purified traditional Chinese medicinal herb that acts as an immunosuppressant and a Ca2+ channel blocker, has been clinically used to treat patients with arthritis, silicosis and hypertension. Since T cells play a critical role as autoreactive and pathogenic population in autoimmune diseases, in this study, we examined the immunosuppressive effect of tetrandrine on human peripheral blood T cells. We showed that tetrandrine inhibited phorbol 12-myristate 13-acetate (PMA) + ionomycin-induced T cell proliferation, interleukin-2 secretion and the expression of the T cell activation antigen, CD71. Further investigation of the molecular mechanism demonstrated that tetrandrine inhibited the expression of the protein kinase C-dependent interleukin-2 receptor alpha chain and CD69 but not the expression of the Ca2+-dependent CD40 ligand and CD69. Interestingly, when tetrandrine and cyclosporin A were added together, significant synergism in the suppression of T cell activation was observed. Moreover, of the several tetrandrine analogues studied, hernandezine was the most potent inhibitor of protein kinase C signaling events. These results also suggest that the protein kinase C-inhibitory capacity of tetrandrine and its analogues may not be associated with their function as Ca2+ channel blockers. Lastly, we showed that, within therapeutic concentrations, tetrandrine and its analogues could induce cellular apoptosis, which is defective in autoimmune diseases. In conclusion, our findings provide novel information about the molecular mechanism of the immunosuppressive effect of tetrandrine and its analogues in human peripheral blood T cells.     

磁感应加热诱导汉防己甲素释放及对肿瘤相关双孔钾离子通道TASK-3的作用研究

目的：构建体外K_2P 9.1（TASK-3）通道过度表达的非洲爪蟾卵母细胞模型;建立外部和磁感应加热2种加热方法,研究其对载汉防己甲素磁性纳米粒中药物释放行为的影响,进一步研究药物及载药磁性纳米粒对TASK-3通道电流的影响。方法：制备载汉防己甲素的聚乳酸-羟基乙酸共聚物（PLGA）磁性纳米粒,采用RP-HPLC考察外部和磁感应加热2种方法对药物释放的影响。采用双电极电压钳技术研究了汉防己甲素、Fe₃O₄-PLGA纳米粒和Tet-Fe₃O₄-PLGA纳米粒及运用磁感应加热诱导药物释放对卵母细胞表面TASK-3通道电流的影响。结果：药物释放量与速率呈现温度依赖性,汉防己甲素对Xenopus oocytes表面TASK-3通道电流有明显抑制作用并呈现剂量依赖性,未载药的PLGA磁性纳米粒对TASK3通道电流不产生影响,而Tet-Fe₃O₄-PLGA NPs在2种加热体系下均显示出对TASK-3通道明显的抑制作用。结论：Tet-Fe₃O₄-PLGA NPs在磁感应作用下能可控性增加汉防己甲素对TASK3通道电流的阻滞作用,这种应激响应性药物递送系统有望成为基于双孔钾通道K_2P9.1靶向治疗的新方法,并有可能用于其他各种癌症治疗。