黄芪注射液拮抗阿霉素心脏毒性作用的研究

目的：研究黄芪注射液对阿霉素心脏毒性的保护作用及其机制。方法：采用阿霉素体外损伤大鼠心肌线粒体和体内小鼠心脏毒性两种模型,应用生化方法测定黄芪注射液对其心脏毒性的保护作用。结果：阿霉素体外引起大鼠心肌线粒体丙二醛（MDA）水平升高,谷胱甘肽（GSH）含量降低及线粒体肿胀等,黄芪注射液对上述损伤有明显的保护作用。体内实验表明,黄芪注射液对阿霉素引起的小鼠心肌线粒体丙二醛（MDA）、血清肌酸磷酸激酶（CK）、门冬氨酸氨基转移菌（AST）活性水平增高及超氧化物歧化酶（SOD）活性降低等损伤均有较好的保护作用。结论：黄芪注射液能拮抗阿霉素引起的心脏毒性,为临床应用黄芪注射液作为抗肿瘤辅助药物提供了实验依据。     

Connexin 43在银杏叶提取物抗大鼠脑缺血损伤中的作用

目的通过体内体外实验研究缝隙连接蛋白43(Cx43)与EGb761脑缺血神经保护作用的关系,探讨银杏叶制剂EGb761治疗脑缺血的机制。方法在大鼠原代神经细胞中转染荷载Cx43-shRNA的慢病毒,干扰Cx43蛋白表达,同时给予EGb761 200μg/mL处理观察Cx43的表达以及EGb761对Cx43蛋白表达的影响。建立大鼠脑缺血模型,腹腔给予EGb761 50、100 mg/kg,使用HE染色,TTC染色,免疫组化和westernblot方法检测大鼠脑组织细胞的形态变化和大鼠海马Caspase-3,TUNEL阳性细胞,Cx43,p-Cx43蛋白的表达变化。结果 EGb761给药可以减少脑缺血大鼠脑组织梗死面积,显著性抑制脑缺血大鼠海马Caspase-3表达和TUNEL阳性凋亡细胞数目,显著性抑制大鼠海马神经细胞p-Cx43的表达水平。体外培养的大鼠神经细胞转染Cx43-shRNA慢病毒,给予EGb761处理,处理前后神经细胞Cx43/p-Cx43蛋白表达未见明显变化。结论 EGb761可以减轻脑缺血缺氧引起的细胞损伤,其神经保护作用与抑制缺血引起的缝隙连接蛋白Cx43的表达和激活有关。     

三七皂苷对阿霉素致心肌损伤保护作用的研究

目的：研究三七皂苷对阿霉素所致心肌损伤的保护作用及其对阿霉素抗肿瘤活性的影响。方法：15 mg·kg^-1腹腔注射阿霉素造成小鼠急性心肌损伤模型,观察不同剂量三七皂苷(25,50,100 mg·kg^-1)干预对动物血清心肌酶谱指标及心肌组织中抗氧化酶活力的影响；采用大鼠心肌细胞H₉C₂,考察不同质量浓度三七皂苷(625～100 mg·L^-1)减轻阿霉素心肌细胞毒性的作用；以MTT法测定三七皂苷对阿霉素抑制肿瘤细胞生长作用的影响。结果：阿霉素显著升高小鼠血清心肌酶指标,降低心肌组织抗氧化酶活力,不同剂量三七皂苷均能减轻心肌损伤、抑制心肌组织抗氧化酶活力的下降。阿霉素抑制离体培养心肌细胞的活力,三七皂苷能提高细胞存活率,但并不拮抗阿霉素对肿瘤细胞生长的抑制作用。结论：三七皂苷在体内和体外均显示减轻阿霉素心脏毒性的作用,同时并不影响后者抑制肿瘤细胞生长的作用。     

银杏叶提取物对视网膜神经细胞活性的影响

目的测定银杏叶提取物（EGb761）对SD大鼠视网膜神经细胞活性的影响，初步探讨EGb 761对大鼠视网膜神经细胞作用机理。方法建立体外培养大鼠视网膜神经细胞，用MTT法检测不同浓度EGb 761对视网膜神经细胞活性的影响。结果EGb 761对视网膜神经细胞有显著的保护作用，且随浓度的增加，保护作用加大。结论EGb 761有较好的保护视网膜神经细胞的作用。     

健脾理气中药对肝癌端粒酶活性的影响

目的：在体内和体外观察健脾理气中药对端粒酶活性的影响,探讨其抗肿瘤治疗的作用机制。方法：采用TRAP方法,观察H22肝癌荷瘤小鼠在服用健脾理气中药后肿瘤端粒酶活性的变化,以及健脾理气中药对体外培养的人肝癌细胞株SMMC-7721端粒酶活性的影响。结果：体内实验显示中药组端粒酶的活性明显低于对照组(P=0．038)。体外实验表明,健脾理气冲剂对SMMC-7721细胞的端粒酶活性有抑制作用。结论：对肿瘤细胞端粒酶活性的抑制可能是健脾理气中药抗肿瘤作用机制的一部分。     

中药人参、附子及其小复方参附汤抑制阿霉素心脏毒性损伤大鼠细胞凋亡的研究

目的:探讨参附汤对阿霉素心脏毒性损伤大鼠细胞凋亡线粒体途径的影响。方法:采用ELISA法测定心肌细胞线粒体Bcl-2、Bax、cytc、Caspase-9、Caspase-3的含量。结果:阿霉素心脏毒性损伤模型大鼠心肌线粒体Bcl-2含量降低、Bax含量提高,有统计学意义(P<0.05);而Caspase-9、Caspase-3含量均提高,有统计学意义(P<0.05)。结论:阿霉素心脏毒性损伤与细胞凋亡线粒体途径有关,参附汤通过抑制线粒体途径的细胞凋亡,以防治阿霉素毒性损伤,进而保护心肌功能。     

中药葛根素对Adr所致不同时段心肌线粒体损伤的保护

目的：从不同时段观察葛根素（Pue）对阿霉素（Adr）大鼠心肌线粒体损伤的保护作用，为临床Pue防治Adr心脏毒性提供依据。方法：用透射电子显微镜观察线粒体形态，激光扫描共聚焦显微镜观测心肌细胞内钙离子浓度。结果：随着给药时间的推进，线粒体逐渐出现肿胀空泡，钙离子浓度明显升高，但较模型组有显著改善。结论：Pue能改善Adr大鼠心肌线粒体损伤，并能推迟Adr心脏毒性的出现时间。     

生脉注射液对阿霉素所致大鼠心肌线粒体损伤的影响

目的观察生脉注射液(Shengm ai In jection,SM I)对阿霉素(Adriamyc in,ADM)诱导大鼠心肌损伤的影响及机制,并对照提前应用生脉注射液组(SM I I组)与先用阿霉素再用生脉注射液组(SM I II组)对阿霉素心肌损伤的影响程度。方法选用阿霉素诱导大鼠心肌损伤的模型。到期测定心肌线粒体中丙二醛(m alond ialdehyde,MDA)含量、超氧化物歧化酶(superoxid ized d ismutase,SOD)、琥珀酸脱氢酶(succ inate dehydrogenase,SDH),Ca2 -ATP酶活性,并应用电镜观察心肌超微结构改变。结果生脉注射液明显降低心肌线粒体内MDA含量,提高SOD,SDH,Ca2 -ATP酶活性,电镜下心肌损伤明显减轻。结论生脉注射液对阿霉素所引起的心脏毒性具有保护作用,其机理可能是提高对氧自由基的清除和抑制脂质过氧化。     

人参、黄芪、附子、干姜对阿霉素心脏毒性损伤大鼠线粒体途径细胞凋亡的影响

目的:探讨人参、黄芪、附子、干姜对阿霉素心脏毒性损伤大鼠线粒体途径细胞凋亡的影响。方法:采用ELISA法测定心肌线粒体Bcl-2、Bax、cytc、Caspase-9、Caspase-3含量。结果:阿霉素心脏毒性损伤模型大鼠心肌线粒体Bcl-2含量降低、Bax、cytc、Caspase-9、Caspase-3含量均升高,有统计学意义(P<0.05)。结论:Bcl-2、Bax、cytc、Caspase-9、Caspase-3参与了阿霉素心脏毒性损伤的发生、发展过程,人参、黄芪、附子、干姜通过调节线粒体途径的细胞凋亡而达到保护心肌作用。     

银杏提取物EGb761对大鼠肝细胞色素P450及对大鼠和人类固醇代谢和排泄的影响

一些对大鼠的体内、体外试验显示,服用银杏提取物可能影响肝的异生物体代谢和引起药物相互作用,而在人体试验未获得该提取物能调节细胞色素P450(CYP450)酶活性的证据。基于这些相互矛盾的发现,作者研究了银杏叶标准提取物EGb761对大鼠肝CYP450的影响和对大鼠与人类固醇代谢和排     

Antimutagenic in vitro activity of plant polyphenols: Pycnogenol and Ginkgo biloba extract (EGb 761)

Ofloxacin (15 microg/mL) and acridine orange (5 microg/mL) induce mutagenicity by different mechanisms in the photosynthetic flagellate Euglena gracilis. The present study examined whether Pycnogenol (PYC; 5-100 microg/mL) or Ginkgo biloba extract (EGb 761; 5-100 microg/mL) could protect against the mutagenic effects of each of the mutagens and the potential mechanisms underlying such protection. The highest concentration of PYC and EGb 761 effectively reduced the mutagenic activity of both ofloxacin and acridine orange by more than 99% (p < 0.001). Using luminol-dependent photochemical methodology it was demonstrated that EGb 761 and PYC were effective antioxidants. In addition, as determined by spectrophotometry, PYC and EGb 761 bound acridine orange. Both PYC and EGb 761 have been shown to produce dual antimutagenic effects, as evidenced by both antioxidant and physicochemical properties. The findings suggest that EGb 761 and PYC would thus be suitable for future study, not only as antioxidants, but also as antimutagenic agents.     

Involvement of Ca2+, CaMK II and PKA in EGb 761-induced insulin secretion in INS-1 cells

EGb 761, a standardized form of Ginkgo biloba L. (Ginkgoaceae) leaf extract, was recently reported to increase pancreatic beta-cell function. To determine whether EGb 761 elicits insulin secretion directly, we treated INS-1 rat beta cells with EGb 761 and then measured insulin release. Treatment of EGb 761 (50 microg/ml) significantly stimulated insulin secretion in INS-1 cells, compared with untreated control (p<0.05) and the stimulatory effect of EGb 761 on insulin secretion was dose-dependent. To elucidate the mechanism of EGb 761-induced insulin secretion, we investigated the involvement of calcium. The treatment with nifedipine, an L-type calcium channel blocker, prevented EGb 761-induced insulin secretion and furthermore, EGb 761 itself elevated [Ca(2+)](i), suggesting the involvement of calcium in this process. To identity the protein kinases involved in EGb 761-induced insulin secretion, INS-1 cells were treated with different kinase inhibitors and their effects on EGb 761-induced secretion were investigated. KN62 and H89, calium/calmodulin kinase (CaMK) II and protein kinase A (PKA) inhibitor, respectively, significantly reduced EGb 761-induced insulin secretion. Immunoblotting studies showed an increase in the phosphorylated-forms of CaMK II and of PKA substrates after EGb 761 treatment. Our data suggest that EGb 761-induced insulin secretion is mediated by [Ca(2+)](i) elevation and subsequent activation of CaMK II and PKA.     

银杏叶提取物EGb761对海马神经元氧糖剥夺后神经元凋亡及Bcl-2蛋白表达的影响

目的:通过观察银杏叶提取物(extract of ginkgo biloba,EGb761)对氧糖剥夺处理的原代培养海马神经元凋亡及Bcl-2蛋白表达的影响,探讨EGb761对脑缺血的神经保护作用。方法:采用海马神经元培养氧糖剥夺损伤(OGD)模型,分为正常对照组、OGD组及EGb761组,观察神经元凋亡及抗凋亡蛋白Bcl-2表达情况。结果:EGb761组较OGD组能明显减少神经元凋亡,上调Bcl-2表达(P<0.05)。结论:EGb761对氧糖剥夺处理后的海马神经元具有明显保护作用。     

Suppression of experimental abdominal aortic aneurysms in the mice by treatment with Ginkgo biloba extract (EGb 761)

Ethnopharmacological relevance

Ginkgo biloba extract (EGb 761) is widely used to treat cerebral disorders. Clinical trials have demonstrated therapeutic benefits of EGb 761 in various vascular diseases. Because the potential pathophysiological mechanisms appear similar to those involved in aneurysmal degeneration, we postulated that EGb 761 might affect the development and progression of experimental abdominal aortic aneurysm (AAA). This study was aimed to investigate whether EGb 761 influences the development of experimental AAAs, and to explore the underlying mechanisms.

Material and methods

C57/BL6 mice underwent abluminal application of CaCl₂ to the abdominal aorta followed by gavages with either 200 mg/kg EGb 761 per day or vehicle. Six weeks after AAA induction, aortic tissue was excised for further examinations.

Results

EGb 761 treatment reduced the aneurysm size compared with vehicle-treated controls. EGb 761 had no effect on hemodynamics or macrophage infiltration in the aortic wall. However, nuclear factor κB protein levels were decreased in the aortas of EGb 761 treated animals. The increased ROS production, SOD and CAT activities, and mRNA expression of p47phox nicotinamide adenine dinucleotide phosphate oxidase were attenuated by EGb 761 treatment. Moreover, administration of EGb 761 preserved the destruction of the wavy morphology of the elastin during AAA formation. Zymographic activity of matrix metalloproteinase (MMP)-9 and MMP-2 was lowered in EGb 761 treated mice.

Conclusions

These results suggest that treatment with EGb 761 in mice prevented the development of CaCl₂-induced AAA. The possible mechanisms include decreased oxidative damage and inflammation, preservation of aortic wall architecture, and altered MMPs activities.     

Antarth, a polyherbal preparation protects against the doxorubicin-induced toxicity without compromising its Antineoplastic activity

Doxorubicin (DOX), an anthracycline drug widely used for the treatment of various cancers, causes a cumulative dose-dependent cardiotoxicity that is characterized by an irreversible dilated cardiomyopathy and congestive heart failure. Antarth (ANT) a polyherbal preparation was evaluated for its cardioprotective properties against doxorubicin-induced cardiotoxicity in mice. Mice were treated with 25 mg/kg ANT orally once daily for 5 consecutive days before a single intraperitoneal injection of 15 mg/kg doxorubicin. The animals were killed 30 h after DOX treatment. DOX induced a significant elevation in the serum levels of glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), creatine kinase (CK-MB) and lactate dehydrogenase (LDH), indicating its acute cardiotoxicity. The treatment of mice with ANT before DOX administration significantly reduced the serum levels of GPT, GOT, CK-MB and LDH indicating that ANT protected against the DOX-induced cardiotoxicity. Pretreatment of mice with 25 mg/kg ANT inhibited the DOX-induced decline in the antioxidant status. Intraperitoneal injection of 1.25 mg/kg DOX once daily for 9 consecutive days significantly improved the survival of mice bearing Ehrlich ascites carcinoma (EAC). Treatment of EAC with 25 mg/kg ANT alone did not affect the anticancer activity of DOX since ANT did not alter the tumor cell growth, the median survival time and average survival time of tumor bearing mice. The present study demonstrates that ANT protects mice against DOX-induced cardiotoxicity, without compromising the antineoplastic activity of DOX.     

天麻素对同型半胱氨酸诱导的细胞因子表达的影响

目的：研究天麻素对同型半胱氨酸诱导的小胶质细胞白介素-1β（IL-1β）、白介素-6（IL-6）和肿瘤坏死因子-α（TNF-α）表达的影响,并对其结果与银杏叶提取物EGb761进行比较。方法：将体外培养的小鼠小胶质瘤细胞（BV-2细胞）分成空白对照组、同型半胱氨酸组、EGb761组（100mg／L）和天麻素低、中、高（2．5、5、10mmol／L）剂量组,培养72h。应用RT—qPCR方法评价IL-1β、IL-6和TNF-αmRNA表达,酶联免疫吸附法（ELISA）测定培养上清中上述细胞因子的蛋白浓度。结果：与对照组相比,同型半胱氨酸组细胞内IL—18、IL-6和TNF—dmRNA表达和细胞培养上清液中蛋白浓度明显增加;与同型半胱氨酸组相比,EGb761组和天麻素各组细胞因子mRNA表达及培养上清液中蛋白浓度均降低,尤其是高剂量天麻素组与EGb761组作用相当,结果均具有统计学意义（P〈0．05）。结论：天麻素能抑制同型半胱氨酸诱导的小胶质细胞IL-1β、IL-6和TNF-α表达,在一定浓度条件下其作用不亚于银杏叶提取物。     

银杏叶提取物的心肌延迟保护作用及其机制研究

目的观察银杏叶提取物(EGb761)对大鼠离体心脏心肌的延迟保护作用及其机制。方法离体大鼠心脏全心停灌缺血30min后再灌注30min产生缺血再灌损伤,观测心率(HR)、冠脉流量(CF)、左室内压(LVP)和左室内压变化最大速率( dp/dtmax),测定心肌组织中肌酸激酶(CK)释放量、心肌组织丙二醛(MDA)和一氧化氮(NO)的量。结果实验前24h单次ig给予EGb761(50或100mg/kg)可显著改善心肌缺血再灌注所致的心功能(LVP和 dp/dtmax)损伤,抑制心肌组织CK释放和MDA水平的增加以及NO水平的降低。预先给予NO合酶抑制剂L-NAME(5mg/kg)或心肌肌细胞膜ATP敏感钾通道(sarcKATP)阻断药HMR1883(3mg/kg),均可明显抑制EGb761对心肌缺血再灌注损伤的延迟保护作用。结论EGb761对缺血再灌注诱导大鼠心肌损伤具有延迟性保护作用,这一保护作用可能与增加NO合成和开放sarcKATP通道有关。