金芪降糖片联合胰岛素激活PPAR-α/FGF21信号改善2型糖尿病大鼠胰岛素抵抗

目的 考察金芪降糖片联合胰岛素对2型糖尿病大鼠胰岛素抵抗的改善作用及作用机制。方法 采用高脂饲料喂养联合ip 3次小剂量（35 mg/kg）链脲霉素制备2型糖尿病大鼠模型,选择空腹血糖值>11.1 mmol/L的大鼠进行后续实验。模型大鼠随机分为模型组、金芪降糖片（0.5 g/kg）组、胰岛素（6.5 IU/kg）组和联合给药（金芪降糖片0.5 g/kg+胰岛素6.5 IU/kg）组,另选取10只健康大鼠作为对照组。各组均每天给药1次,连续给药4周,检测大鼠餐后2 h血糖并进行胰岛素耐量试验（ITT）,Elisa方法检测大鼠血清成纤维细胞因子21（FGF21）含量,Western Bloting检测大鼠肝脏PPAR-α表达情况。结果 与对照组比较,模型组餐后血糖明显升高（P<0.01）,胰岛素敏感性、肝脏PPAR-α均显著降低（P<0.01）,血清FGF21升高,但无显著性差异;与模型组比较,联合给药能明显降低2型糖尿病大鼠餐后血糖（P<0.01）,显著增加胰岛素敏感性（P<0.05）,显著升高血清FGF21含量（P<0.01）、增加肝脏PPAR-α表达（P<0.01）,且较两药单用效果更优。结论 金芪降糖片联合胰岛素具有改善2型糖尿病大鼠胰岛素抵抗、增加胰岛素敏感性的作用,其机制可能与协同激活PPAR-α/FGF21信号有关。     

替米沙坦对非酒精性脂肪性肝炎大鼠脂联素及PPAR-γ表达的影响

目的 探讨替米沙坦对非酒精性脂肪性肝炎大鼠脂联素及PPAR-γmRNA表达的影响. 方法 35只雄性SD大鼠随机分为正常对照组(n=10)、模型组(n=15)和替米沙坦干预组(n=10). 模型和药物干预组给予高脂饲料喂养16周诱发脂肪性肝炎,其中药物干预组于高脂喂养12周后,给予替米沙坦(5 mg&#8226;kg-1&#8226;d-1)灌胃治疗4周. 检测空腹血糖、空腹胰岛素和胰岛素抵抗指数(HOMA-IR);应用逆转录 聚合酶链反应(RT-PCR)方法 测定大鼠肝组织脂联素及PPAR-γmRNA的表达;ELISA法测定血清脂联素水平. 结果与正常对照组比较,模型组空腹血糖、空腹胰岛素和HOMA-IR均显著性升高(P<0.01),药物干预组上述指标较模型组显著下降(P<0.01). 与正常对照组比较,模型组血清脂联素及肝组织脂联素、PPAR-γmRNA水平均显著降低(P<0.01);药物干预组的血清脂联素及肝组织脂联素、PPAR-γmRNA较模型组均升高(P<0.05). 结论 替米沙坦对非酒精性脂肪性肝炎有防治作用.     

GLP-1类似物对糖尿病心肌病大鼠心脏组织PPAR-α、ET-1表达的影响

目的探讨GLP-1类似物对PPAR-α、ET-1在糖尿病心肌病大鼠心脏组织表达的影响。方法 30只雄性SD大鼠高糖高脂饲料喂养四周后腹腔注射链脲菌素(STZ)制备糖尿病模型,随机分为糖尿病心肌病组、小剂量治疗组、大剂量治疗组。给予不同剂量的Exendin-4治疗6周后测各组血脂、血糖,同时采用HE染色法、Masson染色法观察心脏病理形态学改变。免疫组织化学法观察心脏组织PPAR-α、ET-1的表达。结果小剂量治疗组和大剂量治疗组与糖尿病心肌病组相比心肌纤维化以及血糖、血脂明显改善(P<0.05),PPAR-α表达明显上升,ET-1表达明显下降(P<0.05)。大剂量治疗组与小剂量治疗组相比,心肌纤维化、血糖、血脂、PPAR-α、ET-1的表达变化更明显。结论 GLP-1类似物对糖尿病心肌病大鼠心肌纤维化具有一定的改善作用,且具有剂量依赖性。     

复方丹参片对颈动脉粥样硬化兔PPAR-γ/LXR-α/ABCA1信号通路的影响

目的：通过动物实验阐明复方丹参片对颈动脉粥样硬化兔PPAR-γ/LXR-α/ABCA1信号通路的影响。方法：高脂饲料加空气干燥法建立兔颈动脉粥样硬化模型,并用100mg/kg和100mg/kg剂量的复方丹参片进行治疗后,经耳缘静脉抽血后空气栓塞处死兔,迅速剥离颈动脉,并检测各组动物血脂含量、颈动脉病理学变化及兔颈动脉中PPAR-γ、LXR-α及ABCA1的表达。结果：复方丹参片能显著降低兔血清总胆固醇、三酰甘油、低密度脂蛋白(P<0.01);并能抑制内膜增生,减少脂质沉积,增加PPAR-γ、LXR-α及ABCA1 mRNA及蛋白质的表达(P<0.01)。结论：复方丹参片可能通过激活PPAR-γ/LXR-α/ABCA1信号通路而发挥抗动脉粥样硬化作用。     

23-乙酰泽泻醇B对肥胖模型小鼠糖脂代谢紊乱的改善作用

目的:研究23-乙酰泽泻醇B对肥胖模型小鼠糖脂代谢紊乱的改善作用及机制。方法:小鼠给予高脂饲料10周以复制肥胖模型。将造模成功的小鼠随机分为模型组、奥利司他组(阳性对照,15.6 mg/kg)和23-乙酰泽泻醇B低、中、高剂量组(7.5、15、30 mg/kg),每组10只;另设置喂养普通饲料的小鼠10只为正常组。正常组和模型组小鼠灌胃水,给药组小鼠灌胃相应药物,灌胃体积均为20 mL/kg,每天1次,连续4周。末次给药后,测定小鼠的体质量、腰围和全身脂肪、肌肉和体液质量;测定小鼠血清中血脂指标[总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C)]和血糖水平;采用酶联免疫吸附法测定肝组织中过氧化物酶体增殖剂激活受体γ(PPAR-γ)、核因子κB(NF-κB)、白细胞介素6(IL-6)水平和血清中肿瘤坏死因子α(TNF-α)水平;采用苏木精-伊红染色法观察小鼠脂肪和肝组织的病理变化。结果:与正常组比较,模型组小鼠体质量、腰围、全身脂肪和体液质量均显著增加(P<0.01);血清中TC、TG、HDL-C、血糖、TNF-α水平和肝组织中PPAR-γ、NF-κB、IL-6水平均显著升高(P<0.05或P<0.01);脂肪细胞结构破裂、体积增大,伴有炎性细胞浸润;大量肝细胞水肿,细胞浆疏松淡染,伴有脂肪变性。与模型组比较,23-乙酰泽泻醇B各剂量组小鼠体质量、全身脂肪和体液质量以及血清中TG、TNF-α水平均显著降低(P<0.01);23-乙酰泽泻醇B中、高剂量组小鼠血清中TC、血糖和肝组织中IL-6均显著降低(P<0.05或P<0.01),肝组织中PPAR-γ水平均显著升高(P<0.05或P<0.01);23-乙酰泽泻醇B高剂量组小鼠腰围和肝组织中NF-κB显著减少或降低(P<0.01);23-乙酰泽泻醇B中剂量组小鼠血清中HDL-C水平显著降低(P<0.01);脂肪细胞排列紧密、体积较小;肝细胞轻中度肿胀,少量细胞浆疏松淡染或呈空泡状,少量肝细胞伴脂肪变性和炎性细胞小灶性浸润。结论:23-乙酰泽泻醇B可改善肥胖模型小鼠的糖脂代谢紊乱,其作用机制可能与调节肝组织中PPAR-γ、NF-κB、IL-6水平和血清中TNF-α水平有关。     

还原型谷胱甘肽片改善酒精性肝损伤的作用及机制研究*

目的：探讨还原性谷胱甘肽片对酒精性肝损伤小鼠模型的保护作用及机制。方法：60只雄性ICR小鼠均分6组：空白组、模型组、水飞蓟宾组、还原型谷胱甘肽片（200、400、800 mg·kg-1）3个剂量组。采用50%的乙醇溶液连续灌胃小鼠6周的方法,构建小鼠酒精性肝损伤动物模型,采用还原性谷胱甘肽片灌胃治疗模型小鼠,检测小鼠体质量、肝脏指数、血清生化指标（ALT、AST、ALP、TC、TG、LDL-c、HDL-c）、肝脏炎症（TNF-α、HMGB-1、IL-6）基因表达水平及肝脏脂滴空泡数,研究还原性谷胱甘肽片的保肝作用。结果：与空白组相比,模型组肝脏指数、血清生化指标（ALT、AST、ALP、TC、TG、LDL-c）、肝脏炎症（TNF-α、HMGB-1、IL-6）基因表达和因子水平均显著升高（P<0.01、P<0.05）,血清中HDL-c水平显著下降（P<0.01、P<0.05）,脂滴空泡数显著增加（P<0.01）;还原型谷胱甘肽片（200、400、800 mg·kg-1）治疗后,模型动物肝脏指数血清（ALT、AST、ALP、TC、TG、LDL-c）、肝脏（TNF-α、HMGB-1、IL-6）基因表达和因子水平均显著降低（P<0.01、P<0.05）,血清中HDL-c水平显著升高（P<0.01、P<0.05）,肝脏细胞病理状态改善,脂滴空泡数显著减少（P<0.01、P <0.05）。结论：还原性谷胱甘肽片能够对酒精性肝损伤小鼠模型具有保护作用,其机制可能与减轻肝脏炎症和减少脂滴沉积有关。     

还原型谷胱甘肽片改善酒精性肝损伤的作用及机制研究*

目的：探讨还原性谷胱甘肽片对酒精性肝损伤小鼠模型的保护作用及机制。方法：60只雄性ICR小鼠均分6组：空白组、模型组、水飞蓟宾组、还原型谷胱甘肽片（200、400、800 mg·kg-1）3个剂量组。采用50%的乙醇溶液连续灌胃小鼠6周的方法,构建小鼠酒精性肝损伤动物模型,采用还原性谷胱甘肽片灌胃治疗模型小鼠,检测小鼠体质量、肝脏指数、血清生化指标（ALT、AST、ALP、TC、TG、LDL-c、HDL-c）、肝脏炎症（TNF-α、HMGB-1、IL-6）基因表达水平及肝脏脂滴空泡数,研究还原性谷胱甘肽片的保肝作用。结果：与空白组相比,模型组肝脏指数、血清生化指标（ALT、AST、ALP、TC、TG、LDL-c）、肝脏炎症（TNF-α、HMGB-1、IL-6）基因表达和因子水平均显著升高（P<0.01、P<0.05）,血清中HDL-c水平显著下降（P<0.01、P<0.05）,脂滴空泡数显著增加（P<0.01）;还原型谷胱甘肽片（200、400、800 mg·kg-1）治疗后,模型动物肝脏指数血清（ALT、AST、ALP、TC、TG、LDL-c）、肝脏（TNF-α、HMGB-1、IL-6）基因表达和因子水平均显著降低（P<0.01、P<0.05）,血清中HDL-c水平显著升高（P<0.01、P<0.05）,肝脏细胞病理状态改善,脂滴空泡数显著减少（P<0.01、P <0.05）。结论：还原性谷胱甘肽片能够对酒精性肝损伤小鼠模型具有保护作用,其机制可能与减轻肝脏炎症和减少脂滴沉积有关。     

泽泻多糖激活PPAR-γ/LXR-α/ABCG1信号通路发挥对糖尿病肾病大鼠的保护作用

目的 探究泽泻多糖对糖尿病大鼠肾损伤的改善作用。方法 SPF级SD雄性大鼠随机分为对照组,模型组,吡格列酮［过氧化物酶体增殖物激活受体γ（PPAR-γ）激活剂,20 mg·kg^-1］组,泽泻多糖低、中、高剂量（100、200、400 mg·kg^-1）组和泽泻多糖（400 mg·kg^-1）＋ GW9662（PPAR-γ抑制剂,10 mg·kg^-1）组,除对照组外均采用高糖高脂＋链脲佐菌素（STZ）柠檬酸钠缓冲液法制备糖尿病肾病（DN）大鼠模型,造模后各组ig给药,每天1次,连续6周。血糖仪测定大鼠空腹血糖（FBG）水平;全自动生化分析仪检测大鼠血清肌酐、尿酸、尿素氮水平,检测24 h尿蛋白及尿肌酐,计算内生肌酐清除率（Ccr）;处死大鼠,计算大鼠肾脏指数;HE染色观察大鼠右侧肾脏组织病理学变化;Western blotting法检测肾脏组织PPAR-γ/肝X受体-α（LXR-α）/ATP结合盒转运蛋白G1（ABCG1）、肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）蛋白水平。结果 与对照组比较,模型组大鼠毛色枯黄,体质量显著减轻（P<0.05）;肾小球细胞空泡化、肾小球基底膜增厚;肾脏指数、FBG、24 h尿蛋白、尿酸、尿素氮、TNF-α和IL-1β蛋白水平显著升高（P<0.05）,Ccr和PPAR-γ、LXR-α、ABCG1蛋白水平显著降低（P<0.05）;与模型组比较,吡格列酮组和中、高剂量泽泻多糖组大鼠毛色及饮食、饮水逐渐恢复,体质量显著增加（P<0.05）;肾损伤程度减轻;FBG、24 h尿蛋白、尿酸、TNF-α和IL-1β蛋白水平显著降低（P<0.05）,Ccr及PPAR-γ、LXR-α、ABCG1蛋白水平显著升高（P<0.05）;泽泻多糖高剂量组肾脏指数显著降低（P<0.05）。高剂量泽泻多糖组与吡格列酮组各指标差异比较无统计学意义,GW9662可逆转高剂量泽泻多糖对大鼠肾脏功能的保护作用。结论 泽泻多糖可能通过激活PPAR-γ/LXR-α/ABCG1通路保护DN大鼠肾脏。     

卷柏提取物改善高脂血症大鼠肝脏脂肪变及 肝脏保护作用的实验研究

目的: 采用高脂饲料喂养法建立大鼠高脂血症模型,研究卷柏提取部位（A,B,C,D）对此大鼠模型肝脏的影响。方法：健康雄性Wistar大鼠70只,除正常对照组10只大鼠给予基础饲料外,其余均给予高脂饲料喂养,4周后尾部采血,测量血液中总胆固醇（TC）、三酰甘油（TG）的含量。根据TC值将大鼠随机分为模型组、阳性对照组、卷柏A组、卷柏B组、卷柏C组和卷柏D组（n=10）。连续给药16周后处死,给药的同时给予高脂饲料。计算大鼠的体重增长情况和肝脏指数,检测血清中丙氨酸氨基转移酶（ALT）、天冬氨酸转氨酶（AST）和肝脏中TC,TG,高密度脂蛋白胆固醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）、脂联素（APN）、肿瘤坏死因子-α（TNF-α）、极低密度脂蛋白（VLDL）的水平。结果:给药16周后,卷柏A组和D组的ALT,AST,TC,TG,TNF-α水平均显著低于模型组（P<0.05,P<0.01）,APN,VLDL水平均显著高于模型组（P<0.05,P<0.01）,并且D组用药量明显低于A组,相当于A组用药量的1/4。结论:卷柏提取物对高脂血症大鼠肝脏有一定的调节作用,能降低脂肪在肝脏中积聚,有保护肝脏的作用。卷柏提取物减少脂肪在肝脏中积聚、改善肝脏脂肪变的作用可能与其提高肝脏中VLDL水平有关;卷柏提取部位D可能是其主要活性部位。     

雷公藤红素调控NLRP3炎症小体改善大鼠代谢相关脂肪性肝病研究

目的 评价雷公藤红素对高脂饮食诱导的代谢相关脂肪性肝病（MAFLD）大鼠的保护作用,并探讨其可能的作用机制。方法 60只健康雄性Wistar大鼠,随机分为6组：对照组、模型组、水飞蓟素胶囊组（阳性对照,100 mg·kg⁻¹）和雷公藤红素低、中、高剂量（125、250、500 μg·kg⁻¹）组,每组10只。对照组给予普通饲料喂养,其余5组给予高脂饲料喂养建立MAFLD模型,造模4周后,从第5周开始给药,ig给予相应剂量的药物至第8周。记录大鼠体质量和肝脏湿质量,计算肝脏系数;腹主动脉取血,检测大鼠血清中丙氨酸氨基转移酶（ALT）、天冬氨酸氨基转移酶（AST）、三酰甘油（TG）、总胆固醇（TC）、低密度脂蛋白-胆固醇（LDL-C）、高密度脂蛋白-胆固醇（HDL-C）、肿瘤坏死因子-α（TNF-α）和白细胞介素-1β（IL-1β）水平;HE染色观察肝脏病理变化;Western blotting法检测肝脏中NOD样受体热蛋白结构域相关蛋白3（NLRP3）和半胱氨酸蛋白酶-1（Caspase-1）蛋白表达水平。结果 与模型组比较,雷公藤红素各剂量组的肝脏病理学表现均有所改善,肝脏系数均显著降低（P＜0.05、0.01）;中、高剂量组大鼠血清中TC、TG、LDL-C、AST、ALT、TNF_-α和IL-1β水平均显著降低（P＜0.05、0.01）;肝脏中NLRP3和Caspase-1的蛋白表达显著减少（P＜0.05、0.01）。结论 雷公藤红素可明显减轻MAFLD大鼠的肝脏病理学损伤,改善血脂水平,其机制可能与调控NLRP3通路密切相关。     

联合用药进行抗肿瘤治疗的研究进展

近年来联合用药逐渐成为肿瘤治疗的研究热点,联合用药可以通过发挥药物的协同抗肿瘤作用,达到在减小化疗药物毒副作用的同时增加药物抗肿瘤效果的目的.本文综述了近年来联合用药用于肿瘤治疗的相关研究,包括:抗体-药物偶联物、多药耐药逆转剂联合抗肿瘤药、基因治疗联合抗肿瘤药以及光动力疗法联合抗肿瘤药,为联合用药的设计及应用提供参考.     

土元乳液对胃癌化疗药物增效作用的体外研究

目的：比较土元乳液对胃癌化疗药物的体外增效作用。方法：采用MTT法体外药敏试验分别测定土元乳液与羟基喜树碱（HCPT）、氟尿嘧啶（5-Fu）、奥沙利铂（Oxa）、多西紫杉醇（泰素帝）体外对人胃癌细胞系BGC-823细胞株的药物敏感性，通过Weeb系数比较细胞生存率（fa），分析土元乳液对其体外增效作用，得出土元乳液最佳体外增效药物。结果：土元乳液对HCPT、Oxa的高中低3个剂量组体外药敏试验增效作用较好，增效作用明显高于5-Fu、泰素帝组（P〈0．05）。结论：土元乳液对HCPT、Oxa有更高的体外增效作用，从而有益于临床上合理配伍用药，更能有效提高临床上联合化疗对肿瘤的抑制率。     

肿瘤时辰治疗的研究与探索

大量研究表明抗肿瘤化疗药物具有昼夜节律性。按照时辰药理学原理进行肿瘤时辰治疗，对于减少不良反应，增加最大耐受量，提高疗效方面的优越性，已为现代临床研究证实。现综述各类时辰化疗药物的特性，阐明药物化疗的疗效与毒性和昼夜节律有关，同时说明放疗也存在着时辰依赖性。开展肿瘤时辰治疗正日益受到重视。     

Nanotechnology-based combinational drug delivery: an emerging approach for cancer therapy

Combination therapy for the treatment of cancer is becoming more popular because it generates synergistic anticancer effects, reduces individual drug-related toxicity and suppresses multi-drug resistance through different mechanisms of action. In recent years, nanotechnology-based combination drug delivery to tumor tissues has emerged as an effective strategy by overcoming many biological, biophysical and biomedical barriers that the body stages against successful delivery of anticancer drugs. The sustained, controlled and targeted delivery of chemotherapeutic drugs in a combination approach enhanced therapeutic anticancer effects with reduced drug-associated side effects. In this article, we have reviewed the scope of various nanotechnology-based combination drug delivery approaches and also summarized the current perspective and challenges facing the successful treatment of cancer.     

Sesquiterpenes: natural products that decrease cancer growth

Despite recent advances in our understanding of the biological processes leading to the development of cancer, there is still a need for new and effective agents to help bring this disease under control. One of the oldest and most effective strategies for developing new chemotherapeutics is the isolation and evaluation of chemicals of natural origin. The importance of natural products for drug discovery has been impressive: One has to only look at the number of clinically active drugs that are used in cancer therapy to see how many are either natural products or are based on natural products. It is also apparent that materials from natural sources are excellent probes (indicators) for cellular targets that, when modulated, may have a deleterious effect upon the survival or proliferation of tumor cells. And the search goes on. Sesquiterpenes are a class of naturally occurring molecules that have demonstrated therapeutic potential in decreasing the progression of cancer. These molecules are 15-carbon isoprenoid compounds that are typically found in plants and marine life. Although this class of compounds has frequently provided encouraging leads for chemotherapeutics, they have not been evaluated as potential anticancer agents. In this review, we provide a current overview of sesquiterpenoids that have potential as anticancer agents.     

Functions of the breast cancer resistance protein (BCRP/ABCG2) in chemotherapy

The breast cancer resistance protein, BCRP/ABCG2, is a half-molecule ATP-binding cassette transporter that facilitates the efflux of various anticancer agents from the cell, including 7-ethyl-10-hydroxycamptothecin, topotecan and mitoxantrone. The expression of BCRP can thus confer a multidrug resistance phenotype in cancer cells, and its transporter activity is involved in the in vivo efficacy of chemotherapeutic agents. Thus, the elucidation of the substrate preferences and structural relationships of BCRP is essential to understanding its in vivo functions during chemotherapeutic treatments. Single nucleotide polymorphisms (SNPs) have also been found to be key factors in determining the efficacy of chemotherapeutics, and those therapeutics that inhibit BCRP activity, such as the SNP that results in a C421A mutant, may result in unexpected side effects of the BCRP- anticancer drugs interaction even at normal dosages. In order to modulate the BCRP activity during chemotherapy, various compounds have been tested as inhibitors of this protein. Estrogenic compounds including estrone, several tamoxifen derivatives in addition to phytoestrogens and flavonoids have been shown to reverse BCRP-mediated drug resistance. Intriguingly, recently developed molecular targeted cancer drugs, such as the tyrosine kinase inhibitors imatinib mesylate, gefitinib and others, can also interact with BCRP. Since both functional SNPs and inhibitory agents of BCRP modulate the in vivo pharmacokinetics and pharmacodynamics of its substrate drugs, BCRP activity is an important consideration in the development of molecular targeted chemotherapeutics.     

Multi-functional polymeric nanoparticles for tumour-targeted drug delivery

The use of nanoparticles as drug delivery vehicles for anticancer therapeutics has great potential to revolutionise the future of cancer therapy. As tumour architecture causes nanoparticles to preferentially accumulate at the tumour site, their use as drug delivery vectors results in the localisation of a greater amount of the drug load at the tumour site; thus improving cancer therapy and reducing the harmful nonspecific side effects of chemotherapeutics. In addition, formulation of these nanoparticles with imaging contrast agents provides a very efficient system for cancer diagnostics. Given the exhaustive possibilities available to polymeric nanoparticle chemistry, research has quickly been directed at multi-functional nanoparticles, combining tumour targeting, tumour therapy and tumour imaging in an all-in-one system, providing a useful multi-modal approach in the battle against cancer. This review will discuss the properties of nanoparticles that allow for such multiple functionality, as well as recent scientific advances in the area of multi-functional nanoparticles for cancer therapeutics.     

Caspase-mediated pro-apoptotic interaction of panaxadiol and irinotecan in human colorectal cancer cells

Objectives Panaxadiol is a purified sapogenin of ginseng saponins that exhibits anticancer activity. Irinotecan is a second‐line anticancer drug, but clinical treatment with irinotecan is limited due to its side effects. In this study, we have investigated the possible synergistic anticancer effects of panaxadiol and irinotecan on human colorectal cancer cells and explored the potential role of apoptosis in their synergistic activity. Key findings The combination of panaxadiol and irinotecan significantly enhanced antiproliferative effects in HCT‐116 cells (P < 0.05). Cell cycle analysis demonstrated that combining irinotecan treatment with panaxadiol significantly increased the G1‐phase fractions of cells, compared with irinotecan treatment alone. In apoptotic assays, the combination of panaxadiol and irinotecan significantly increased the percentage of apoptotic cells compared with irinotecan alone (P < 0.01). Increased activity of caspase‐3 and caspase‐9 was observed after treating with panaxadiol and irinotecan. The synergistic apoptotic effects were supported by docking analysis, which demonstrated that panaxadiol and irinotecan bound two different chains of the caspase‐3 protein. Conclusions Data from this study suggested that caspase‐3‐ and caspase‐9‐mediated apoptosis may play an important role in the panaxadiol enhanced antiproliferative effects of irinotecan on human colorectal cancer cells.     

Metformin enhancing the antitumor efficacy of carboplatin against Ehrlich solid carcinoma grown in diabetic mice: Effect on IGF-1 and tumoral expression of IGF-1 receptors

Diabetes has been listed as a risk factor for various types of cancer. Cancer cell development can be promoted by increased levels of IGF-1 and hyperinsulinemia that are associated with diabetes type II. Metformin is an anti-diabetic agent and its potential antitumor impact has become the objective of numerous studies. In this vein, we hypothesize that using metformin in diabetes type II mice may synergistic with carboplatin for reducing the risk of cancer. Therefore, the study aimed to evaluate the in vivo antitumor activity of metformin against solid EAC tumor growth in female diabetic mice and its potential pro-apoptotic and anti-proliferative effects with clarification of its inconclusive biological mechanisms. Mice were assigned into nine groups; normal control, diabetic control, diabetic plus EAC control, EAC control, and treated groups received carboplatin and/or metformin (100, 200 mg/kg). Metformin administration especially with high dose potentiated the antitumor activity of carboplatin displayed by increased pro-apoptotic activators “caspase-3 and bax” and reduced anti-apoptotic protein bcl-2. This was confirmed by the histopathological scores. Moreover, the combination therapy was effective in attenuating the expression of the pro-angiogenic mediator “VEGF” and the microvessel density as revealed by the CD₃₄. Additionally, this combination down-regulated the high levels of the mutagenic element “IGF-1” and its receptor expression, and attenuated the intensity of inflammatory mediators. In conclusion, it was found that metformin therapy could enhance apoptotic marker, and suppress the neovascularization and proliferation process. This clarified the ability of metformin to support carboplatin activity in reducing tumor progression in type II diabetes.     

NF-κB-mediated anti-inflammatory activity of the sesquiterpene lactone 7-hydroxyfrullanolide

Metformin is an antidiabetic drug with anticancer properties, which mainly acts through induction of AMP-activated protein kinase (AMPK). In the present study we investigated the influence of metformin on the in vitro anticancer activity of the well-known chemotherapeutic agent cisplatin. Cell viability was determined by MTT and LDH release assay, oxidative stress and apoptosis (caspase activation, DNA fragmentation, and phosphatidylserine exposure) were assessed by flow cytometry, while activation of AMPK and Akt was analyzed by immunoblotting. Although metformin reduced the number of tumour cells when applied alone, it surprisingly antagonized the cytotoxicity of cisplatin towards U251 human glioma, C6 rat glioma, SHSY5Y human neuroblastoma, L929 mouse fibrosarcoma and HL-60 human leukemia cell lines. Only in B16 mouse melanoma cells metformin augmented the cytotoxicity of cisplatin. In U251 glioma cells metformin suppressed cisplatin-induced apoptotic cell death through inhibition of oxidative stress and caspase activation. The observed cytoprotection was apparently AMPK-independent, as metformin did not further increase cisplatin-induced AMPK activation in U251 cells and other pharmacological AMPK activators failed to block cisplatin-mediated apoptosis. On the other hand, metformin induced Akt activation in cisplatin-treated cells and Akt inhibitor 10-DEBC hydrochloride or phosphoinositide 3-kinase/Akt inhibitor LY294002 abolished metformin-mediated antioxidant and antiapoptotic effects. In conclusion, the antidiabetic drug metformin reduces cisplatin in vitro anticancer activity through AMPK-independent upregulation of Akt survival pathway. These data warrant caution when considering metformin for treatment of diabetic cancer patients receiving cisplatin or as a potential adjuvant in cisplatin-based chemotherapeutic regimens.