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排序方式: 共有1171条查询结果,搜索用时 15 毫秒
1.
目的:探讨黄连素对人胃癌细胞SGC7901凋亡的影响。方法:MTS法检测不同浓度的黄连素(100、150、200μmol/L)对胃癌细胞的抑制作用,Hoechst 33258染色检测不同浓度的黄连素(100、150、200μmol/L)对细胞凋亡的影响;Real Time Q-PCR检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的mRNA表达;Western blot检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的蛋白表达。结果:不同浓度的黄连素能显著降低人胃癌细胞SGC701活性(P<0.05,P<0.01),促进其凋亡,升高Cleaved Caspase-3、Bax的mRNA和蛋白表达水平(P<0.05,P<0.01),降低Bcl-2的mRNA和蛋白表达水平(P<0.05,P<0.01)。结论:不同浓度的黄连素可诱导胃癌细胞凋亡,其机制可能与升高Cleaved Caspase-3、Bax的表达,降低Bcl-2的表达有关。 相似文献
2.
《药学学报(英文版)》2020,10(9):1769-1783
Atherosclerosis (AS) is the leading cause of heart attacks, stroke, and peripheral vascular disease. Berberine (BBR), a botanical medicine, has diversified anti-atherosclerotic effects but with poor absorption. The aim of this study was to develop an effective BBR-entrapped nano-system for treating AS in high-fat diet (HFD)-fed Apoe(−/−) mice, and also explore the possible underlying mechanisms involved. Three d-α-tocopherol polyethylene glycol (PEG) succinate (TPGS) analogues with different PEG chain lengths were synthesized to formulate BBR-entrapped micelles. HFD-fed Apoe(−/−) mice were administered with optimized formula (BBR, 100 mg/kg/day) orally for 5 months. The artery plaque onset and related metabolic disorders were evaluated, and the underlying mechanisms were studied. Our data showed that, BT1500M increased BBR deposition in liver and adipose by 107.6% and 172.3%, respectively. In the Apoe(−/−) mice, BT1500M ameliorated HFD-induced hyperlipidemia and lipid accumulation in liver and adipose. BT1500M also suppressed HFD-induced chronic inflammation as evidenced by the reduced liver and adipose levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β); and decreased plasma level of TNF-α, IL-6, IL-1β, interferon-γ (IFN-γ), monocyte chemotactic protein (MCP), and macrophage inflammatory factor (MIP). The mechanism study showed that BT1500M changed Ampk and Nf-κb gene expression, and interrupted a crosstalk process between adipocytes and macrophages. Further investigation proved that BT1500M decreased endothelial lesion and subsequent macrophage activation, cytokines release, as well as cholesteryl ester gathering in the aortic arch, resulting in ameliorated artery plaque build-up. Our results provide a practical strategy for treating AS using a BBR-entrapped nano-system. 相似文献
3.
Berberrubine (BRB), the active metabolite of berberine (BBR), possesses various pharmacological activities. In this study, we found BRB showed not only a stronger lipid-lowering effect than berberine but also a specific nephrotoxicity in mice fed with high fat diet (HFD). To explore the underlying mechanism, the pharmacokinetics of BRB were evaluated. There was a greater in vivo exposure of BRB in C57BL/6J mice fed with HFD than with routine chows, in terms of Cmax, AUC0-t, levels of BRB in kidney and urinary excretion. Moreover, in vitro assessment clearly showed BRB had a toxic effect on renal cell lines, while the primary metabolite, berberrubine-9-O-β-d-glucuronide (BRBG), did not show any obvious toxicity. These results suggested HFD aggravated BRB-induced nephrotoxicity by promoting the in vivo exposure of BRB especially in urine and kidney. Although our previous study indicated BRB could be metabolized into BRBG, BRBG did not show any obvious toxicity in vitro. 相似文献
4.
Yang Liu Xiaojia Liu Na Zhang Mingxiao Yin Jingwen Dong Qingxuan Zeng Genxiang Mao Danqing Song Lu Liu Hongbin Deng 《药学学报(英文版)》2020,10(12):2299-2312
Programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) blocking therapy has become a major pillar of cancer immunotherapy. Compared with antibodies targeting, small-molecule checkpoint inhibitors which have favorable pharmacokinetics are urgently needed. Here we identified berberine (BBR), a proven anti-inflammation drug, as a negative regulator of PD-L1 from a set of traditional Chinese medicine (TCM) chemical monomers. BBR enhanced the sensitivity of tumour cells to co-cultured T-cells by decreasing the level of PD-L1 in cancer cells. In addition, BBR exerted its antitumor effect in Lewis tumor xenograft mice through enhancing tumor-infiltrating T-cell immunity and attenuating the activation of immunosuppressive myeloid-derived suppressor cells (MDSCs) and regulatory T-cells (Tregs). BBR triggered PD-L1 degradation through ubiquitin (Ub)/proteasome-dependent pathway. Remarkably, BBR selectively bound to the glutamic acid 76 of constitutive photomorphogenic-9 signalosome 5 (CSN5) and inhibited PD-1/PD-L1 axis through its deubiquitination activity, resulting in ubiquitination and degradation of PD-L1. Our data reveals a previously unrecognized antitumor mechanism of BBR, suggesting BBR is small-molecule immune checkpoint inhibitor for cancer treatment. 相似文献
5.
四氢巴马汀对大鼠心肌缺血再灌注损伤的保护作用 总被引:1,自引:0,他引:1
目的:探讨四氢巴马汀(l-THP)对大鼠心肌缺血再灌注损伤的保护作用。方法:Wistar大鼠24只,分为假手术组、模型组和l-THP治疗组,结扎大鼠冠状动脉左前降支30min再灌注120min造成心肌缺血再灌注损伤模型,分别于缺血30min、再灌注30min、60min、90min、120min观察l-THP对大鼠心功能、心肌酶学和脂质过氧化的影响。结果:l-THP能够对抗心肌缺血再灌注损伤引起的左心室内压(LVSP)、左心室内压最大上升与下降速率(±dp/dtmax)下降,左心室舒张末期压力(LVEDP)的升高,并能够稳定心肌组织Na -K -ATPase和Ca2 -Mg2 -ATPase活性,降低丙二醛(MDA)含量和增高超氧化物歧化酶(SOD)的活性。结论:四氢巴马汀(l-THP)对大鼠心肌缺血再灌注引起的心功能降低具有明显的保护作用,其机制可能与改善能量代谢障碍和抑制自由基生成或清除氧自由基作用有关。 相似文献
6.
目的:对小劈碱(BBR)对大肠杆菌的抑制作用的分子靶点进行探讨。方法:鉴于BBR对DNA结合的偏好性,本文从基因转录表达水平对BBR的大肠杆菌生长抑制作用靶点进行实验研究。结果:BBR对于大肠杆菌基因上游调控元件UP element具有较强的亲和力,而在此元件地转录起始区含有TATA碱基序列。进一步对启动子上游含有UP element调控元件的基因sulA、recA、16S和启动子上游不含UP element调控元件的基因lpxC、secG、mutT的mRNA表达比较表明,BBR抑制sulA、recA、16S的表达,对lpxC、secG、mutT无明显作用,提示TATA序列是BBR的作用靶点。结论:本结果对从基因转录水平探讨BBR抑菌作用提供了新思路。 相似文献
7.
8.
黄连素长久以来一直作为广谱抗菌药物使用,具有显著的抑菌作用,原是治疗肠炎、痢疾的经典中药。近年来发现黄连素在降糖调脂、治疗心内科疾病、肿瘤科疾病等众多方面也有重要作用。现将其在这些方面的临床应用作一综述。 相似文献
9.
目的建立直接数码扫描薄层色谱的影像,利用计算机软件测定黄连提取物中巴马汀、小檗碱、表小檗碱、黄连碱含量的新方法。方法薄层色谱的制备:硅胶高效薄层板;展开剂为乙酸丁酯∶甲醇∶异丙醇∶氨水(25%~28%)=5∶2∶1.5∶1.2;定量操作获得荧光薄层色谱经摄像获取色谱的影像,经专业软件数码扫描,替代常规薄层色谱需采用薄层扫描仪定量的测定方法,利用获取的色谱中小檗碱、巴马汀、表小檗碱、黄连碱斑点的积分值,直接外标法同时测定含量。结果经精密度、准确度、重复性测试,结果符合方法学验证的技术要求。与液相色谱测定的数据比较完全具有可比性。结论用自编计算机软件(‘digiscan’)作为虚拟扫描仪进行数码扫描薄层色谱的影像(薄层色谱视觉数据的永久记录),通用软件Origin Pro积分,外标法计算含量,不需要昂贵的薄层色谱扫描仪,即可进行含量测定,通过黄连提取物中4种生物碱的含量测定,证明这一替代方法用于中药有效成分含量测定的可行性。本法最大优点是不需要昂贵的薄层扫描仪,依靠软件操作,薄层色谱的影像可长期保存,测定不受时间和地点的限制,检测成本效益高。符合中药指标成分含量测定的需求,有推广应用的价值,尤其适合生产企业的全程检验、新药研发过程检验及市场商品的检验。 相似文献
10.