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1.
目的 通过对比研究氧化苦参碱及其磷脂复合物大鼠离体肠吸收情况,考察磷脂复合物对氧化苦参碱肠吸收的影响。方法 采用大鼠离体外翻肠囊模型研究氧化苦参碱磷脂复合物的肠吸收特性。HPLC测定不同剂量的氧化苦参碱及氧化苦参碱磷脂复合物在大鼠十二指肠、空肠、回肠和结肠内的累积吸收量。结果 氧化苦参碱磷脂复合物在不同肠段的吸收较氧化苦参碱均有提高,低剂量组氧化苦参碱磷脂复合物在空肠、结肠处的吸收较氧化苦参碱有显著提高;中剂量组氧化苦参碱磷脂复合物在十二指肠、空肠、结肠处的累积吸收量较氧化苦参碱有显著提高;高剂量组氧化苦参碱磷脂复合物在空肠的吸收较氧化苦参碱有显著提高。结论 与氧化苦参碱相比,磷脂复合物对氧化苦参碱在大鼠肠道的吸收有显著的促进作用。  相似文献   
2.
目的:优选参柏洗剂的制备工艺,为该制剂的工业化生产提供参考。方法:采用水蒸气蒸馏法提取松叶、荆芥中挥发油,通过单因素试验优选提取工艺。以总生物碱质量浓度和固形物总量的综合评分为指标,通过正交试验考察加水量、提取时间、提取次数对参柏洗剂水提工艺的影响,并通过单因素试验筛选浓缩工艺及成型工艺。结果:最佳制备工艺条件为加14倍量水提取5 h,收集含挥发油蒸馏液,加0.1%聚山梨酯80增溶;药渣与其余4味药材加8倍量水煎煮3次,每次1 h,常压或减压浓缩,加入0.3%苯甲酸钠防腐,冷藏48 h除杂。总生物碱质量浓度不低于195 mg·L-1,保留率不低于85%。结论:该工艺稳定可行,可为参柏洗剂的规范化生产提供实验依据。  相似文献   
3.
目的:建立一种简易的测定联合服用苦参素和阿德福韦酯成人血清中苦参素和阿德福韦酯含量方法。方法采用Shim-pack VP-ODS C18色谱柱(250 mm ×4.6 mm,5μm),流动相为甲醇∶水(70∶30),流速为1.1 mL·min -1,检测波长为229 nm。结果苦参素保留时间4.6 min 左右,标准曲线的线性范围为0.0125~2 mg·L -1,r =0.9992。阿德福韦酯保留时间7.3 min 左右,标准曲线的线性范围为0.0125~0.75 mg·L -1,r =0.9991,苦参素和阿德福韦酯的日间、日内变异系数均在7%以下,回收率>92%。结论该法简便,灵敏,快速,可用于苦参素和阿德福韦酯临床联用治疗的成人血药浓度的监测。  相似文献   
4.
目的 探讨氧化苦参碱介导细胞自噬减轻溃疡性结肠炎(ulcerative colitis,UC)小鼠结肠黏膜氧化性损伤的作用机制。方法 采用2,4,6-三硝基苯磺酸灌肠复制小鼠UC模型,将造模成功小鼠按体质量随机分为模型组、氧化苦参碱组(50 mg·kg-1·d-1,ig)、羟基氯喹组(50 mg·kg-1·d-1,ig)、氧化苦参碱+羟基氯喹组,另设正常组,每组10只。治疗1周后测定各组小鼠疾病活动度(disease activity,DAI)、结肠质量系数及病理形态;MitoSOX Red法测定结肠ROS含量,ELISA法测定结肠组织SOD、MDA、MPO、GSH-PX含量;透射电镜结合免疫荧光观测结肠细胞自噬程度,Western blot测定Atg5和Beclin-1蛋白表达。结果 与模型组和羟基氯喹组比较,氧化苦参碱组小鼠DAI和结肠质量系数均有显著减小(P<0.01),结肠病理损伤明显减轻;ROS、MDA和MPO含量极显著降低(P<0.01),SOD和GSH-PX含量极显著增加(P<0.01);结肠黏膜细胞自噬,程度显著增强,Atg5和Beclin-1蛋白表达极显著上调(P<0.01)。结论 氧化苦参碱可促进UC小鼠细胞自噬,减轻小鼠结肠黏膜氧化性损伤。  相似文献   
5.
刘楠  李纳  马晓华  朱琳  时程程 《中草药》2021,52(4):1177-1184
实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)是由CD4+T细胞介导的中枢神经系统脱髓鞘性疾病,是国际公认研究多发性硬化(multiple sclerosis,MS)的动物模型。CD4+T细胞作为EAE模型的主要免疫应答细胞,存在多个亚群,可分泌多种细胞因子,参与病情进展。CD4+T细胞增殖分化及功能紊乱与EAE发病机制密切相关。目前临床尚无治疗MS的有效药物,多以对症应用皮质类固醇激素为主,但不良反应严重,且易产生药物依赖。近年来中药因作用温和、药物安全性较高、成本低、耐受性好等优点逐渐走进大众视野,针对中药对EAE中CD4+T细胞亚群分化的影响展开论述,为临床用药提供更多理论基础。  相似文献   
6.

Background

Sophora flavescens Ait. is a traditional Chinese medicine with a long history in China. It is mainly used in the treatment of heat dysentery and similar ailments in the clinical. The objective of this paper was to isolate, purify and identify alkaloids from Sophora flavescens Ait. and to explore their inhibitory effects on C6 glioma cells.

Materials and Methods

Column chromatography, extraction and NMR spectroscopy were used to structurally identify the isolated compounds. MTT assay and flow cytometry were used to detect the inhibitory effect of matrine on C6 cells.

Results

Three compounds were isolated from Sophora flavescens Ait., namely matrine, oxymatrine and lupeol. Different concentrations of matrine solution all had inhibitory effects on growth of C6 cell lines, which showed apparent dose-effect relationship. Compared with the control group, proportion of G0/G1 phase cells increased in each matrine concentration group to a maximum of 79.8%; proportion of S phase cells reduced, and proportion of G2/M phase cells declined slightly to a minimum of 6.3%, suggesting that after the action of matrine proliferation of C6 cells was significantly inhibited and the cells were arrested in the G1 phase.

Conclusion

We concluded that Sophora flavescens Ait. has an inhibitory effect on C6 cell proliferation.  相似文献   
7.
苦参碱类生物碱(包括有苦参碱、氧化苦参碱、氧化槐定碱、槐果碱、氧化槐果碱等)具有镇痛作用,镇痛特征是以中枢性为主、无成瘾性和耐药性,综述其镇痛作用及作用机制研究进展。苦参碱类生物碱的中枢性镇痛作用机制可能是:激活大麻素受体-2和上调电压门控钙离子N-型通道表达,促进抑制性神经递质(γ-氨基丁酸、甘氨酸)合成和释放,下调GAT-1表达,使突触间隙γ-氨基丁酸浓度升高以及上调γ-氨基丁酸-A受体表达,从而增强γ-氨基丁酸能神经功能。γ-氨基丁酸能神经功能的增强可抑制兴奋性神经递质谷氨酸过度表达并下调NMDA受体和蛋白激酶Cγ表达,降低NMDA受体对谷氨酸的兴奋性,从而下调电压门控钙离子L-型通道的表达,抑制钙离子内流,阻滞CaMKⅡ/CREB通路,减轻炎症反应和产生镇痛作用。  相似文献   
8.
目的观察氧化苦参碱(oxymatrine,OXY)对青霉素(penicillin,PEN)致痫大鼠学习记忆功能和海马神经元形态的影响。方法成年SD大鼠48只随机分为生理盐水对照组(normal saline,NS)、癫痫模型组(epilepsy,EP)、氧化苦参碱组(OXY)和苯巴比妥钠阳性对照组(PBS),腹腔注射青霉素诱导大鼠癫痫发作,观察大鼠行为学改变,Morris水迷宫检测大鼠空间学习和记忆,观察大鼠海马区神经元细胞形态学改变。结果通过Morris水迷宫视频跟踪系统观察各组大鼠在A区和C区停留的时间和在A区和C区游泳路径的长度,PBS组和OXY组在A区的停留时间和在A区的游泳路径比EP组明显增长(P<0.05),对大鼠空间记忆能力有所改善。NS组神经细胞结构正常;EP组可见神经细胞肿胀、细胞器的损伤等改变;PBS组变性坏死程度较轻,大部分神经细胞胞膜都较完整;OXY组神经元细胞肿胀明显减轻,细胞器等损伤能够得到改善。结论 OXY可以对癫痫大鼠在空间学习和记忆方面起到保护作用。  相似文献   
9.
Background  Oxymatrine has certain antiviral effects in the treatment of chronic hepatitis B (CHB), but its exact mechanism is unclear. The objective of the present study was to explore oxymatrine’s antiviral mechanism by studying its effect on the hepatitis B virus (HBV) specific cytotoxic T lymphocyte (CTL) surface programmed death receptor-1 (PD-1) expression in CHB patients.
Methods  Sixty-five CHB patients who had HBV DNA³104 copies/ml, positive HBeAg, positive human leukocyte antigen (HLA)-A2, alanine aminotransferase (ALT) >2´upper limit of normal value (ULN) were randomly divided into two groups: treatment group (n=33), treated with an intravenous infusion of 600 mg oxymatrine in glucose solution once a day for a month, then with a 200 mg oxymatrine oral capsule three times a day, and a 200 mg silibin meglumine tablet three times a day; control group (n=32) patients were treated only with silibin meglumine tablet, method and dosage were the same as those of treatment group. Three months later, peripheral blood HBV-specific CTL surface PD-1 expression, HBV-specific CTL level, HBV DNA, HBeAg, and results of liver function tests were analyzed and compared.
Results  Three months post-treatment, in the treatment group, peripheral blood HBV-specific CTL surface PD-1 expression ((19.42±15.94)%) decreased significantly compared to the pretreatment level ((31.30±24.06)%; P <0.05), and decreased significantly compared to that of control group three months after treatment ((29.45±21.62)%; P <0.05). HBV-specific CTL level ((0.42±0.07)%) significantly increased compared with the pretreatment ((0.29±0.15)%; P <0.01), and the control group posttreatment level was (0.31±0.15)% (P <0.05). HBV DNA level in 11 cases became negative (HBV DNA<500 copies/ml, 33.33%), which was higher than that of the control group after treatment (two cases, 6.25%; χ2=7.45, P <0.01), HBeAg of nine cases turned negative (27.27%), which was higher than that of the control group after treatment (one case, 3.13%; χ2=7.27, P <0.01).
Conclusion  Oxymatrine could downregulate peripheral blood HBV-specific CTL surface PD-1 expression in CHB patients, increase HBV-specific CTL level, which may be one of the possible mechanisms by which oxymatrine clears or inhibits HBV in CHB patients.
  相似文献   
10.
Objective:To investigate the effects of oxymatrine on hepatic gene expression profile in a rat model of liver fibrosis.Methods:Forty healthy male SD rats were randomly divided into three groups,a normal group(n=8),a model group(n=16),and an oxymatrine treatment group(n=16).Experimental hepatic fibrosis was induced by subcutaneous injection of carbon tetrachloride(CCI4).The rats in the treatment group received oxymatrine via celiac injection at a dosage of 40 mg/kg once a day at the same time.The rats in the model and normal groups received saline at the same dosage via celiac injection.Serum levels of aspartate aminotransferase (AST),alanine transarninase(ALT),alkaline phosphatase(AKP),hyaluronic acid(HA),and laminin(LN)were assayed.The deposition of collagen was observed with HE and Masson staining.Effect of oxymatrine on hepatic gene expression profile was detected by oligonucleotide microarray analysis with Affymetrix gene chip rat U230A. Quantitative real-time polymerase chain reaction(QRT-PCR)was carried out to confirm the expression changes of six genes.Results:Oxymatrine significantly improved liver function,lowered serum levels of HA and LN,and decreased the degree of liver fibrosis,compared with the model group(P<0.05).A total of 754 differentially expressed genes were identified by gene chip between the model group and the normal group,among which 438 genes increased and 316 genes decreased over two folds.Compared with the model group,86 genes were downregulated markedly in the oxymatrine group(P<0.05),including collagen I and other genes related to extracellular material(ECM),integrin signal transduction genes,early growth response factor genes,and proinflammatory genes;28 genes were upregulated significantly(P<0.05),including cytochrome P450(CYP450) superfamily genes,glycolipids metabolism and biological transformation related genes.Six genes were confirmed with QRT-PCR,consistent with the result from microarray.Conclusion:Oxymatrine could affect the expression of many functional genes and may be useful in the prevention and treatment of liver fibrosis.  相似文献   
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