四物汤传统汤剂与配方颗粒的有效成分比较研究

目的 建立四物汤传统汤剂与配方颗粒的有效成分比较研究的质量特征.方法 采用薄层色谱法对处方中的当归、芍药进行定性鉴别;采用高效液相色谱法测定处方里当归中的阿魏酸和芍药中的芍药苷含量.结果 薄层色谱检出当归、芍药的特征斑点;阿魏酸的质量浓度在22.9~617.3ng范围内、芍药苷质量浓度在30.5~2469.1ng范围内时,其各自的积分面积与进样量呈现良好的线性关系(r=0.9995,0.9996),阿魏酸的平均回收率为97.46%,RSD为1.24%;芍药苷的平均回收率为98.13%,RSD为1.07%.结论 该种方法精密度良好,内稳定性好,操作简捷准确,重复性好,可用于四物汤传统汤剂与配方颗粒的有效成分的比较研究,为四物汤在临床上的应用提供一定参考.     

中药对药物代谢酶的影响

药物代谢酶在众多中西药物代谢中起着非常重要的作用.本文综述了近年来国内外学者就中药对药物代谢酶影响的研究思路、方法和进展.通过深入研究中药对药物代谢酶活性的影响,有利于中药基础理论的深入和发展;临床上应该重视中药与其他药物合用时所发生的代谢性相互作用,优化给药方案,从而提高临床用药的有效性和安全性.     

植物药及果蔬对药物代谢酶P450活性的影响

中草药及其他植物药在我国及东南亚国家应用广泛，在欧美也逐渐受到重视，一些中草药及植物药可能诱导或抑制肝脏细胞色素P450(CYP)药物代谢酶，从而引起自身及其他合用药物代谢的改变，因此可能导致药物不良反应和药物相互作用。     

探究黑胡椒粉对SD大鼠肝脏七种主要P450酶亚型的影响

目的进行大鼠体内外实验探究黑胡椒粉对肝脏七种主要P450酶亚型的影响。方法采用体外探针底物孵育法结合LC-MS/MS技术测定黑胡椒粉乙醇提取物与大鼠肝微粒体共孵育各时间点七种酶亚型的酶活力;采用Cocktail探针法结合LC-MS/MS技术测定体内连续灌胃黑胡椒粉一、二和三天大鼠肝脏七种酶亚型的酶活力。结果与对照组相比,黑胡椒粉乙醇提取物在体外实验中对大鼠CYP2D2、CYP3A、CYP2C11、CYP2E1和CYP1A2具有抑制作用;与空白组相比,灌胃黑胡椒粉一天对大鼠CYP2A5、CYP2D2和CYP1A2具有明显的诱导作用,且诱导作用在连续灌胃二和三天随之减弱。结论黑胡椒粉对大鼠肝脏P450酶有诱导作用,且经P450酶代谢产生的代谢产物是其诱导作用的物质基础。     

口服黄芩素对大鼠药物代谢酶的影响

目的:考察口服黄芩素对大鼠肝细胞色素P450(CYP450)、谷胱甘肽-S-转移酶(GST)和尿苷二磷酸-葡萄糖醛酸转移酶(UGT)活性的影响。方法:大鼠连续7 d口服200 mg.kg-1黄芩素后,差速离心法制备肝微粒体和肝胞浆,采用特异性探针底物法测定肝微粒体CYP450酶系6种同工酶活性的变化,采用比色法检测GST和UGT活性的变化。结果:大鼠口服黄芩素对CYP2C9,CYP2E1,GST和UGT有显著的抑制作用,抑制率分别为26.76%,29.12%,37.45%和70.86%(P<0.05或0.01),对CYP1A2,CYP2C19,CYP2D6和CYP3A4没有明显的影响。结论:其他药物与黄芩素合用时,需考虑可能由于代谢酶活性变化引起的药物相互作用。     

食物对细胞色素P450药物代谢酶的影响

细胞色素P450酶系在大多数内源性和外源性分子的生物氧化过程中发挥重要的作用,尤其在药物代谢方面。CYP450酶个体差异大,除了遗传因素的影响外,食物等外界因素也可能影响其活性或表达,从而影响经酶代谢药物的疗效和不良反应。故本文就食物因素对细胞色素P450酶影响的相关研究进行综述。     

半枝莲粗提物对小鼠肝脏药物代谢酶的调节作用

目的通过研究半枝莲水提物和乙醇提取物对昆明（KM）小鼠细胞色素P450酶（CYP）、谷胱甘肽S-转移酶（GST）活性的抑制作用,研究半枝莲与其他药物合用时可能发生的相互作用。方法按照随机对照原则,以半枝莲水提物和乙醇提取物1、2和5g·kg^-1·d^-1剂量为低、中和高剂量连续灌胃给药5d,以HPLC方法检测探针药及其代谢产物量来表示相应酶的活性;以分光光度法测定细胞溶质中GST酶活性。结果与对照组比较,中、高剂量半枝莲水提物组与乙醇提取物组CYP2C与CYP3A活性显著下降;高剂量水提物组GST活性显著下降;而各组CYP2D与CYP2E1活性未见改变。结论半枝莲水提物和乙醇提取物对KM小鼠的细胞色素P450酶和GST活性都有不同程度的抑制作用,呈现出剂量相关性。     

布格呋喃与大鼠肝脏药物代谢酶的相互作用

目的：研究参与布格呋喃代谢的CYP450同工酶类型和体外代谢的酶促动力学特征,并观察口服布格呋喃对大鼠肝脏药物代谢酶的影响。方法：采用比色／动态荧法光及UV—HPLC法检测大鼠口服布格呋喃（8mg&#183;kg^-1&#183;d^-1,连续3日）后肝脏CYP450同工酶（CYP1A2、2C6、2C11、2D2、2E1和3A2）和Ⅱ相酶-谷胱甘肽巯基转移酶（GST）、尿苷二磷酸葡萄糖醛酸转移酶（UDPGT）和谷胱甘肽还原酶（GR）活性。应用肝微粒体温孵法测定布格呋喃体外代谢速率（Vmax和米氏常数Km）。比较布格呋喃在正常及高诱导大鼠肝微粒体中代谢速率的差异以及CYP1A2、2C6、2C11、2D2、2E1和3A2的选择l生抑制剂（呋拉茶碱、磺基苯吡唑、奥美拉唑、奎尼丁、戒酒硫和酮康唑）对布格呋喃代谢的抑制程度,鉴定参与布格呋喃代谢的CYP450同工酶类型。结果：布格呋喃在乙醇、地塞米松和3-甲基胆葸诱导大鼠肝微粒体中的Km、Vmax分别为正常组的11倍、6倍和1.3倍;应用CYP3A2、2E1和IA2的选择性抑制剂酮康唑、戒酒硫和呋拉茶碱可不同程度地抑制布格呋喃的代谢,使代谢速率下降为对照组的34％、47％和78％。     

草甘膦对大鼠肝微粒体酶活力的影响及其机理初探

运用体内试验和体外试验的方法，研究了草甘膦对大鼠肝微粒体酶活力的影响，并对其作用机理进行了初步探讨。结果表明，体内试验中，草甘膦能明显增加细胞色素Ｐ４５０含量，诱导氨基比林Ｎ－脱甲基酶（ＡＰＮＤ）和乙基吗啡Ｎ－脱甲基酶（ＥＭＮＤ）的活力；体外试验中，在３．３×１０－８～３．３×１０－４ｍｏｌ／Ｌ浓度范围内，未见草甘膦对Ｐ４５０含量有明显增加，而在２×１０－６ｍｏｌ／Ｌ和２．５×１０－５～２×１０－４ｍｏｌ／Ｌ浓度范围内可分别对ＡＰＮＤ和ＥＭＮＤ呈现诱导作用，在２×１０－８～２×１０－４ｍｏｌ／Ｌ浓度范围内，随草甘膦浓度增高，ＡＰＮＤ和ＥＭＮＤ活力均有上升趋势。初步观察结果，草甘膦在体内对肝微粒体酶诱导作用机理与其促进蛋白质合成作用有关。     

四物汤效应成分基于CYP酶的相互作用研究

目的研究四物汤效应成分果糖、阿魏酸、芍药苷和川芎嗪及其配伍对CYP同工酶的抑制及诱导作用,为从代谢角度解释中药方剂的配伍规律提供依据。方法应用人肝微粒体体外孵育模型和探针底物代谢产物的LC-MS/MS定量方法,评价各单药及药对配伍组对CYP酶同工酶CYP1A2、2B6、2C9、2C19、2D6和3A4的抑制作用。应用"三明治"培养的大鼠原代肝细胞模型,评价各单药及其药对配伍组对CYP1A和CYP3A的诱导作用。结果果糖、阿魏酸、芍药苷、川芎嗪及其配伍组(100μmol·L-1),对人肝微粒体CYP1A2、2B6、2C9和2C19的抑制率均<62%,对CYP3A4和CYP2D6的活性无影响。各单药及配伍组对CYP3A1/2无明显的诱导作用;芍药苷及其药对和配伍(50μmol·L-1)对CYP1A2诱导活性的提高>阳性诱导剂的40%。结论四物汤各成分及其药对配伍对6个主要CYP同工酶均无明显的抑制作用,芍药苷单药对CYP1A2有一定诱导作用,与果糖、阿魏酸和川芎嗪配伍时,诱导活性明显增强。     

甘草水煎液对大鼠肝微粒体细胞色素P450酶活性的影响

目的：观察甘草水煎液对大鼠肝细胞色素P450酶活性的影响。方法：SD大鼠随机分为4组,分别为空白对照组（给予生理盐水）、酶诱导剂组（给予苯巴比妥）、酶抑制剂组（给予西咪替丁）及甘草水煎液组（给予甘草水煎液）,各组动物连续灌胃给药14 d,第15天腹腔注射探针药物非那西丁,不同时间点采集血样后,HPLC法测定血浆中非那西丁浓度,并估算其药代动力学参数。结果：生理盐水组、苯巴比妥组、西咪替丁组及甘草水煎液组非那西丁的t1/2分别为（104±10）、（178±15）、（86±9）、（90±9）min。结论：甘草水煎液对大鼠肝药酶P450具有一定的诱导作用。     

六味地黄丸对大鼠肝微粒体代谢酶P450活性的影响

目的:考察六味地黄丸对大鼠肝微粒体代谢酶P450活性的影响.方法:大鼠灌胃分别给予生理盐水、西咪替丁、苯巴比妥钠和六味地黄丸7 d后,腹腔注射非那西丁,不同时间点采集血样,用HPLC法测定血浆中探针药物非那西丁的浓度,用DAS软件估算其药动学参数.结果:生理盐水组、西咪替丁组、苯巴比妥钠组和六味地黄丸组探针药物的t1/2分别为(93.5±9.2),(161.7±11.0),(85.4±9.0),(67.0±6.7)min.结论:六味地黄丸对大鼠肝微粒体代谢酶P450活性有一定的诱导作用.     

丹参活性成分或制剂对CYP450活性的影响及药物相互作用研究进展

丹参是一种传统医疗的草本植物,临床上广泛应用于心脑血管疾病的辅助治疗。丹参活性成分复杂,部分成分可影响肝脏中细胞色素P450酶（CYP450）的活性,可能导致药物相互作用的发生。探讨丹参对CYP450活性的影响及药物相互作用机制,对指导临床合理联用丹参与其他药物具有重要的意义。     

Effects of coffee and its chemopreventive components kahweol and cafestol on cytochrome P450 and sulfotransferase in rat liver.

Coffee drinking appears to reduce cancer risk in liver and colon. Such chemoprevention may be caused by the diterpenes kahweol and cafestol (K/C) contained in unfiltered beverage. In animals, K/C treatment inhibited the mutagenicity/tumorigenicity of several carcinogens, likely explicable by beneficial modifications of xenobiotic metabolism, particularly by stimulation of carcinogen-detoxifying phase II mechanisms. In the present study, we investigated the influence of K/C on potentially carcinogen-activating hepatic cytochrome P450 (CYP450) and sulfotransferase (SULT). Male F344 rats received 0.2% K/C (1:1) in the diet for 10 days or unfiltered and/or filtered coffee as drinking fluid. Consequently, K/C decreased the metabolism of four resorufin derivatives representing CYP1A1, CYP1A2, CYP2B1, and CYP2B2 activities by approximately 50%. For CYP1A2, inhibition was confirmed at the mRNA level, accompanied by decreased CYP3A9. In contrast to K/C, coffee increased the metabolism of the resorufin derivatives up to 7-fold which was only marginally influenced by filtering. CYP2E1 activity and mRNA remained unchanged by K/C and coffee. K/C but not coffee decreased SULT by approximately 25%. In summary, K/C inhibited CYP450s by tendency but not universally. Inhibition of CYP450 and SULT may contribute to chemoprevention with K/C but involvement in the protection of coffee drinkers is unlikely. The data confirm that the effects of complex mixtures may deviate from those of their putatively active components.     

地塞米松对大鼠肝脏微粒体细胞色素P-450的诱导效应

目的:观察地塞米松(dexamethasone,DEX)对细胞色素P-450(cytochrome P450,CYP450)的诱导效应,并探讨其诱导机制.方法:雄性Wistar大鼠分别以DEX 0,25,50和100mg·kg-1·d-1诱导处理(ip)4d后,测定大鼠肝脏总CYP450含量,CYP3A1,CYP3A2和CYP2B 1/2的mRNA及蛋白的表达水平,肝脏ERD(CYP3A活性),PROD(CYP2B活性)和BROD(总CYP450活性).结果:CYP450含量、ERD、PROD和BROD活性在DEX多次诱导后都有升高.CYP3A1 mRNA表达水平、蛋白含量和酶活性有明显的升高,剂量效应关系明显;CYP3A2蛋白明显升高,但mRNA表达水平却无明显变化.PROD和CYP2B1/2的mRNA表达水平以及总CYP450含量均在50mg·kg-1·d-1剂量组达到最高值.结论:DEX对雄性大鼠主要诱导CYP3A1和CYP3A2两个CYP450成员表达上调,对CYP2B1/2也有一定的诱导作用,其诱导作用主要表现在酶活性、酶蛋白含量和mRNA表达水平的升高.CYP3A1和CYP3A2的诱导方式可能不同.     

Effect of natamycin on cytochrome P450 enzymes in rats

Natamycin is a polyene macrolide antibiotic widely used in the food industry as a feed additive to prevent mold contamination of foods. There are many contradictory results on the genotoxic effects of macrolides which could suggest a potential risk for humans. In the present study, the effects of natamycin on the activities of some drug metabolizing enzymes in rat liver microsomes were determined in vivo. Rats were treated orally with natamycin at doses of 0.3, 1, 3 and 10 mg/kg body weight (bw)/day for 6 days. Determinations of cytochrome P450 (CYP) enzyme activities were carried out in hepatic microsomes isolated from rats treated. The activities of CYP2E1, CYP1A1/2 CYP2B1/2 and CYP4A1/2 enzymes significantly decreased after treatment with 1, 3 and 10 mg/kg bw/day, in a dose-dependent manner as compared to control. This effect was not observed after natamycin treatment at dose of 0.3 mg/kg bw/day. Our results suggest that natamycin may not potentiate the toxicity of many xenobiotics via metabolic activation and/or accumulation of reactive metabolites but also might affect the clearance of other xenobiotics detoxified by the studied CYP enzymes.     

Effects of photoisomers of cyclodiene insecticides on liver and microsomal cytochrome P450 in rats

Threshold dosages of the photoisomers of cyclodiene insecticides, namely photochlordane, photodieldrin, and photoheptachlor, for the induction of hepatic microsomal cytochrome P450 (P450) and liver hypertrophy in male rats were at least one-quarter of those reported for corresponding parent cyclodienes. Maximum increase in total P450 concentration (30%) and demethylases activities (100%) was always respectively one-third or one-tenth of that reported for parent cyclodienes. The P450 isozymic form induced by photoheptachlor resembled that induced by pentobarbital (P4502B1) in its substrate specificity, spectral characteristics, and electrophoretic mobility. The induction of P450 was initially followed by hepatic hypertrophy. However, higher dosages of photoisomers caused wasting and lowered both the liver weight and the activity of aniline hydroxylase while those of mirex and endrin, which also caused wasting and lowered aniline hydroxylase activity, continued causing further hepatic hypertrophy.     

淫羊藿苷对不同月龄大鼠肝微粒体细胞色素P450的影响

目的 揭示淫羊藿苷(Ica)对大鼠肝微粒体细胞色素P450的含量及部分亚型的影响,并比较月龄的差异.方法 ig给予6月龄和18月龄的♂SD大鼠Ica( 60 mg· kg -1),4周后取肝脏,用钙沉淀法提取肝微粒体,BCA法测定微粒体蛋白浓度;用一氧化碳还原差示光谱法测定CYP450的含量;用ELISA法测定CYP1 A1、CYPb5的含量;用比色法测定苯胺羟化酶(反映CYP2E1活性)和红霉素-N-脱甲基酶(反映CYP3A活性)的活性;用real - time RT - PCR检测CYP1 A1、CYP2A3、CYP2E1、CYP3A1、CYP3A2和CYP4B1 mRNA的表达.结果 60 mg· kg-1 Ica明显增加了CYP450的总酶和CYP1 A1的含量、CYP3A的活性及CYP1 A1、CYP3A1、CYP3A2 mRNA的表达,降低了CYP2E1的活性及其mRNA的表达;但Ica对上述各指标的诱导或抑制作用在大鼠月龄方面差异不明显;Ica对CYPb5的含量及CYP2A3、CYP4B1 mRNA的表达未见明显影响.结论 Ica对大鼠肝微粒体CYP450总酶、CYPI A1和CYP3A具有诱导作用,对CYP2E1具有抑制作用,该作用未见明显月龄差异.     

Effects of Phyllanthus amarus on the pharmacokinetics of midazolam and cytochrome P450 activities in rats

Phyllanthus amarus, a commonly used medicinal herb, was investigated for possible herb-drug interactions. The effect on CYP3A-mediated drug metabolism in rats after single dose administration of P. amarus extract was investigated using midazolam (MDZ) as a probe substrate. The effect of multiple dose administration of P. amarus extract on activity and expression of various CYP isoforms were studied. Oral administration of P. amarus extract (800?mg/kg) 1?h before oral MDZ increased the C(max) and AUC(0--∞) of MDZ by 3.9- and 9.6-fold and decreased the clearance by 12%, but did not alter the pharmacokinetics of intravenous MDZ. Daily administration of P. amarus extract (200 or 800?mg/kg/day) for 15 days in rats increased the activity and expression of CYP3A and CYP2B1/2. In contrast, the activities and expressions of CYP1A, CYP2C and CYP2E1 were not significantly changed. The dual effects of P. amarus extract on CYP enzymes were demonstrated. Single dose administration of the extract increased oral bioavailability of MDZ through inhibition of intestinal CYP3A whereas repeated administration of the extract slightly induced hepatic CYP3A and CYP2B1/2 in rats, which suggested that herb-drug interactions by P. amarus may potentially occur via CYP3A and 2B.     

Effects of Phyllanthus amarus on the pharmacokinetics of midazolam and cytochrome P450 activities in rats

1. Phyllanthus amarus, a commonly used medicinal herb, was investigated for possible herb–drug interactions. The effect on CYP3A-mediated drug metabolism in rats after single dose administration of P. amarus extract was investigated using midazolam (MDZ) as a probe substrate. The effect of multiple dose administration of P. amarus extract on activity and expression of various CYP isoforms were studied.

2. Oral administration of P. amarus extract (800?mg/kg) 1?h before oral MDZ increased the C_max and AUC_0–-∞ of MDZ by 3.9- and 9.6-fold and decreased the clearance by 12%, but did not alter the pharmacokinetics of intravenous MDZ.

3. Daily administration of P. amarus extract (200 or 800?mg/kg/day) for 15 days in rats increased the activity and expression of CYP3A and CYP2B1/2. In contrast, the activities and expressions of CYP1A, CYP2C and CYP2E1 were not significantly changed.

4. The dual effects of P. amarus extract on CYP enzymes were demonstrated. Single dose administration of the extract increased oral bioavailability of MDZ through inhibition of intestinal CYP3A whereas repeated administration of the extract slightly induced hepatic CYP3A and CYP2B1/2 in rats, which suggested that herb–drug interactions by P. amarus may potentially occur via CYP3A and 2B.