心血管药物速效救心丸和通心络胶囊对大鼠细胞色素P450酶的影响

目的:观察速效救心丸和通心络胶囊对大鼠药物代谢酶细胞色素P450(CYP450)的影响。方法:给予大鼠试验药物后制备肝及小肠微粒体,CO还原差示光谱法测定肝微粒体CYP450含量,蛋白免疫印迹法检测肝微粒体中CYP1A2、CYP2C11、CYP2E1、CYP3A和肠微粒体中CYP3A蛋白的表达量。结果:速效救心丸组和通心络胶囊组与空白对照组比较,大鼠肝脏CYP450含量无显著变化(P>0.05);但是West-ern blotting实验对肝脏和肠道中多种CYP450酶表达量测定的结果显示,速效救心丸可诱导肝脏CYP1A2表达,但抑制肝脏CYP2C11和肠道CYP3A表达(P<0.05);通心络胶囊可诱导大鼠肝脏CYP1A2、CYP2E1蛋白表达(P<0.05)。结论:速效救心丸和通心络胶囊对大鼠肝脏CYP450酶总量无影响,但是,在蛋白质水平对特定亚型蛋白的表达量有影响,由此可能引发的药物相互作用不容忽视。     

双环醇对肝脏部分切除大鼠CYP450酶活性和表达的影响(英文)

本研究考察双环醇对肝脏部分切除(PH)后大鼠肝脏微粒体细胞色素P450(CYP)活性、基因和蛋白表达的影响及相关机制。大鼠PH前灌胃给予双环醇(300 mg.kg-1)3次,PH后处死大鼠,取其血清和肝组织进行检测,依次测定血清谷丙转氨酶(ALT)、肝微粒体丙二醛(MDA)和肝脏总CYP含量、4种CYP同工酶活性、基因和蛋白表达。结果显示,双环醇可显著抑制PH大鼠血清ALT和肝微粒体MDA的升高,抑制肝脏总CYP含量的减少,抑制CYP2C6、2C11活性和mRNA表达的下降,明显抑制CYP3A1/2活性的下降,并上调CYP3A1和2E1的mRNA和蛋白表达。结果表明,双环醇对PH大鼠肝脏CYP450酶及部分同工酶活性和表达的改变有明显改善作用,其作用机制可能与其抗氧化作用和酶诱导作用密切相关。     

参麦注射液对大鼠心脏细胞色素P450酶的调节作用

目的研究参麦注射液及各单药注射液对大鼠心脏P450酶mRNA表达和花生四烯酸代谢的影响。方法 SD大鼠连续腹腔注射参麦注射液及各单药注射液14 d后取心脏,采用实时荧光定量PCR(RT-q PCR)方法,检测各处理组药物对大鼠心脏P450亚酶CYP1A1、CYP1B1、CYP2B1、CYP2C11、CYP2E1、CYP2J3、CYP4A1、CYP4A3、CYP4F1、CYP4F4、CYP4F5、CYP4F6、ANP、BNP、EPHX2mRNA表达的影响。结果对各处理组的心脏P450酶mRNA表达水平检测显示:与空白组比较,除CYP2B1、CYP4A3和CYP4F6参麦注射液对其他CYP各亚型mRNA的表达均表现了上调的作用,红参注射液组对CYP2E1、CYP4A3、CYP4F1和EHPX2mRNA表达有上调作用,麦冬注射液对ANP、BNP和EHPX2mRNA的表达上调作用明显,同时能明显下调CYP2B1和CYP2C11的表达。结论虽然参麦注射液对CYP2B1的作用没有统计学意义,但总体呈现出诱导的趋势,而麦冬注射液对CYP2B1呈现明显的抑制作用,提示红参注射液可能对CYP2B1的诱导作用更大。参麦注射液、红参注射液与麦冬注射液均对CYP2E1、CYP4F1和EHPX2有诱导作用,提示参麦注射液对CYP2E1、CYP4F1和EHPX2的诱导作用可能由复方中的红参和麦冬共同贡献。参麦注射液和麦冬注射液对ANP和BNP均具有诱导的作用,提示在对ANP和BNP的作用中麦冬比红参的作用更强。同时参麦注射液对心血管疾病疗效明确,可能与其对CYP2J3、ANP和BNP等调节作用较强相关。     

丹红注射液对大鼠肝微粒体5种CYP亚型酶活性的影响

摘要目的研究丹红注射液对5种细胞色素P450亚型酶活性的影响,为临床合理用药提供参考。方法采用大鼠体外肝微粒体孵育法,分别以非那西丁、甲苯磺丁脲、右美沙芬、氯唑沙宗、睾酮为CYP1A2、CYP2C9、CYP2D6、CYP2E1、CYP3A4的探针药物,在大鼠肝微粒体孵育体系中孵育,用高效液相色谱（HPLC）法测定相应的代谢产物,比较空白对照组和丹红注射液低、中、高剂量组之间探针药物代谢率的差异,评价丹红注射液对各亚型酶活性的影响。结果在体外肝微粒体孵育体系中,丹红注射液低剂量组中CYP1A2 和CYP2C9活性与空白对照组相比,差异无统计学意义（P＞0.05）;中和高剂量组中CYP1A2和CYP2C9活性与空白对照组相比降低,差异有统计学意义（P＜0.05或P＜0.01）;丹红注射液低、中、高剂量组中CYP2D6、CYP2E1、CYP3A4的活性与空白对照组相比,差异无统计学意义（P＞0.05）。丹红注射液对大鼠肝微粒体CYP1A2酶活性的半数抑制浓度（IC50）和抑制常数（Ki）分别为0.54%和0.226%。结论丹红注射液对大鼠肝微粒体CYP1A2酶活性有抑制作用,且为混合型抑制;对CYP2C9有弱抑制作用;对CYP2D6、CYP2E1、CYP3A4酶活性无明显影响。     

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.     

苦碟子注射液对大鼠肝微粒体CYP450酶5个亚型的体外抑制作用

目的研究苦碟子注射液对大鼠肝微粒体CYP450酶的体外抑制作用。方法制备大鼠肝微粒体。将苦碟子注射液分别与混合探针药物非那西丁、甲苯磺丁脲、奥美拉唑、睾酮和氯唑沙宗共同孵育,UPLC-MS/MS法检测各探针药物的代谢物。结果在测定浓度范围内,苦碟子注射液对CYP2E1、CYP2C9和CYP2C19的活性抑制率小于50%;对CYP1A2、CYP3A4的IC_(50)值分别为12.68%、8.11%,远高于临床日用药浓度0.20%~0.80%。结论在正常剂量下,苦碟子注射液对大鼠CYP2E1、CYP2C9、CYP2C19几乎不显示抑制作用,对CYP1A2、CYP3A4几乎没有抑制作用。     

柴胡注射液对大鼠细胞色素P450各亚型活性的影响

目的：观察柴胡注射液对大鼠细胞色素P450各亚型活性的影响。方法：24只Wistar大鼠,随机分成3组：对照组,柴胡注射液低、高剂量组。3组分别腹腔注射生理盐水、0.36、0.72mL/kg（相当于原药材0.72、1.44g/kg）柴胡注射液诱导两周后,于d15清晨灌胃给予探针药物咖啡因（10mg/kg）,6h后处死。用HPLC法观察探针药物代谢率的变化来反映柴胡注射液对大鼠CYP1A2活性的影响;West-ernbloting测定大鼠肝微粒体CYP1A2、3A4、4A1蛋白的相对含量。结果：体内、外探针药物代谢率在各剂量组及对照组间均无统计学差异（P〉0.05）,CYP1A2在各剂量组中表达亦无统计学差异。CYP3A4在柴胡注射液高剂量组中表达明显增多（P〈0.05）,CYP4A1在柴胡注射液低、高剂量组表达均明显减少（P〈0.05）。结论：柴胡注射液对大鼠CYP1A2亚型没有影响,但在蛋白质水平,可抑制大鼠肝CYP4A1表达。高剂量柴胡注射液可诱导大鼠肝CYP3A4表达。     

混合探针底物法测定五味子成分对大鼠肝脏细胞色素P450同工酶的影响

研究大鼠多次口服五味子成分和体外对肝脏细胞色素P450酶(CYP450)6种同工酶的影响。采用超速离心法制备正常及多次口服五味子醇/水提物的大鼠肝微粒体并与探针药进行体外温孵,应用液相色谱?串联质谱分析方法测定CYP450的6种同工酶特异性探针底物非那西丁(CYP1A2)、右美沙芬(CYP2D2)、双氯芬酸钠(CYP2C6)、美芬妥英(CYP2C11)、氯唑沙宗(CYP2E1)、咪达唑仑(CYP3A1/2)在大鼠肝微粒体的代谢产物生成(对乙酰氨基酚、右啡烷、4-羟基双氯芬酸钠、4-羟基美芬妥英、6-羟基氯唑沙宗、1-羟基咪达唑仑)以反映各CYP450同工酶活性。五味子醇提物(28～120μg.mL-1)体外对大鼠肝微粒体CYP450的6个同工酶均有不同程度的抑制作用。大鼠多次口服五味子醇提物(1.5 g.kg-1,qd×7d)对肝脏CYP3A1/2和CYP2E1有显著诱导作用,对CYP2D2和CYP2C11有明显抑制作用,而对CYP2C6和CYP1A2无明显影响。五味子水提物(100～500μg.mL-1)体外对大鼠肝脏CYP450同工酶亦有抑制作用;体内多次给药(1.5 g.kg-1,qd×7d)对肝脏CY...     

四物汤及其有效成分对大鼠肝脏主要药物代谢酶的影响

目的研究四物汤及其有效成分对大鼠肝脏P450酶的影响,从药物代谢酶角度为四物汤的配伍规律提供实验依据。方法大鼠口服灌胃四物汤10 g·kg-1·d-1及其有效成分果糖0.334 g·kg-1·d-1,阿魏酸0.002 g·kg-1·d-1,川芎嗪0.011 g·kg-1·d-1,芍药苷0.022 g·kg-1·d-1,连续给药1周后处死,用生理盐水灌流肝脏,制备肝微粒体,采用混合探针与肝微粒体体外孵育法考察四物汤及其有效成分对大鼠肝脏细胞色素P450酶的影响。利用实时定量聚合酶链式反应(Q-PCR)检测四物汤及其有效成分对大鼠肝脏P450 mRNA表达的影响,利用Western blot法检测四物汤及其有效成分对大鼠肝脏CYP2B1蛋白表达的影响。结果肝微粒体孵育结果显示,果糖对CYP1A2、CYP2B6、CYP2C9、CYP2D6酶活性具有抑制作用,阿魏酸对CYP2C9、CYP2B6酶活性具有抑制作用,川芎嗪对CYP1A2、CYP2C9、CYP2B6的酶活性具有抑制作用,芍药苷对CYP2D6、CYP2B6酶活性具有抑制作用。阿魏酸、果糖、芍药苷组对CYP2B1mRNA的表达具有抑制作用,与酶活性水平一致。4种单体成分对CYP2B1蛋白表达具有抑制作用。结论阿魏酸、果糖、芍药苷组在CYP450酶活性、mRNA基因转录水平及蛋白表达水平对CYP2B1均有抑制作用。     

Cocktail 探针药物法评价辣椒素对大鼠CYP450亚型的影响

目的：采用cocktail 探针药物法研究辣椒素在体外对大鼠肝微粒体CYP 450四种亚型的影响。方法：分为试验组和对照组,试验组采用大鼠肝微粒体孵育体系、探针药物和系列浓度的辣椒素（对照组仅加入缓冲液）共同孵育20 min,反应终止后用HPLC方法检测代谢产物的生成量以代表酶的活性。采用Graphpad prism 5.0计算辣椒素对各亚型的IC50值。将辣椒素与大鼠肝微粒体分别预孵育0,5,10,15,20,30 min,计算不同预孵育时间下各亚型的相对活性百分比。结果：辣椒素对大鼠肝微粒体CYP1A2、CYP2C11、CYP2E1和CYP3A2的IC50值分别为36.21,17.19,51.64,18.86μmol·L-1。预孵育没有增强辣椒素对CYP450的抑制作用。结论：辣椒素在体外对大鼠肝微粒CYP1A2、CYP2C11、CYP2E1和CYP3A2具有抑制作用,且未呈现出预孵育时间依赖性。     

雷公藤甲素单次及多次给药对大鼠肝药酶活性的影响

目的:研究雷公藤甲素对大鼠肝药酶活性的影响。方法:对SD大鼠以雷公藤甲素(150、300、450μg·kg-1)灌胃给药,每天1次,给药1d或14d,分别测定细胞色素P450、细胞色素b5含量及红霉素N-去甲基酶(ERD)、二甲基亚硝胺脱甲基酶(NDMA)、甲氧基异唑脱甲基酶(MROD)、乙氧基异唑脱乙基酶(EROD)和戊氧基异唑脱烷基酶(PROD)活性;CYP3A和CYP2E1蛋白含量采用Westernblotting法分析。结果:单次灌胃雷公藤甲素对肝药酶活性及CYP2E1、CYP3A蛋白表达基本无影响;多次给予雷公藤甲素(450μg·kg-1,14d)能诱导NDMA活性,抑制ERD活性,轻度升高CYP2E1蛋白表达,显著降低CYP3A蛋白表达。结论:长期较高剂量给予雷公藤甲素能抑制CYP3A活性,轻度诱导CYP2E1活性。     

灯盏细辛注射液对大鼠肝微粒体CYP3A的抑制作用

目的：研究灯盏细辛注射液对大鼠肝微粒体CYP3A酶活性的抑制作用。方法：在体外大鼠肝微粒体孵育体系中加入底物睾酮和不同体积的灯盏细辛注射液,用高效液相色谱法测定睾酮的羟化代谢产物6β-羟基睾酮的生成量反映CYP3A酶的活性。酮康唑用作阳性对照药。结果：在体外孵育体系中,灯盏细辛注射液对大鼠肝微粒体CYP3A酶活性有抑制作用,IC50和Ki值分别为0.40%和0.24%（V/V）。结论：体外给药灯盏细辛注射液对大鼠肝微粒体CYP3A酶活性有抑制作用,符合混合型抑制模型。     

Differential activities of CYP1A isozymes in hepatic and intestinal microsomes of control and 3-methylcholanthrene-induced rats

Differences in expression of CYP1A isoforms (CYP1A1 and CYP1A2) in liver and small intestine of male Wistar rats and their inducibility by 3-methylcholanthrene as well as the effect of different CYP1A1/1A2 expression on caffeine metabolism were investigated. In rat liver, CYP1A2 is the predominant isoform and CYP1A1 protein expression in liver is significantly increased after treatment by 3-methylcholanthrene. In contrast, only CYP1A1 was detected in control and 3-methylcholanthrene induced small intestine microsomes. Treatment with 3-methylcholanthrene (40 mg/kg intraperitoneally daily during 1, 2, 3 or 4 days) demonstrated that liver CYP1A1 is more sensitive for the induction effects than CYP1A2 and also that significant induction of CYP1A1 in rat small intestine only occurred after 3 to 4 days pretreatment. Caffeine metabolism and inhibition studies by furafylline, CYP1A1 antiserum and ketoconazole revealed that the differences in the expression of CYP1A1 and CYP1A2 in the two tissues led to significant changes in the contribution of the various isoenzymes involved in the biotransformation of caffeine. Whereas in liver paraxanthine formation was almost exclusively catalyzed by CYP1A2, in rat proximal intestine it was formed by CYP1A1. In addition, other CYP enzymes (most probably CYP3A) play a significant role in theobromine and theophylline formation from caffeine in rat intestine. Overall, this study shows different expression and inducibility of CYP1A1/1A2 by 3-methylcholanthrene in rat liver and small intestine. Furthermore in rat intestine cytochrome P450 isozymes such as CYP1A1 and CYP3A replace CYP1A2 in the caffeine metabolism.     

Effects of duration of phenytoin administration on mRNA expression of cytochrome P450 and P-glycoprotein in the liver and small intestine of rats

Phenytoin (5,5-diphenylhydantoin; DPH) induces expression of cytochromes P450 (CYPs). Interactions between DPH and tacrolimus suggested that the persistence of CYP induction after discontinuation of DPH is dependent on the history of administration and dosing period of DPH. However, the relationship between the duration of DPH administration and expression of CYPs in the liver and small intestine of rats is not known. Alterations in levels of P-glycoprotein (P-gp; MDR1; ABCB1) as well as CYPs cause drug interactions in the small intestine. We examined the effects of the duration of DPH administration on expression of CYPs and P-gp in the liver and small intestine of rats. Rats were treated with DPH (100 mg/kg, peroral (p.o.) twice a day (b.d.)) for 2, 4, 8, and 16 d. mRNA levels of CYPs and P-gp were examined using the total RNA extracted from the liver and duodenum 2 h and 24 h after the final administration of DPH. CYP3A activities were determined using microsomes. DPH administration for 2 d and 4 d markedly increased mRNA levels of CYPs such as CYP3A1, CYP3A2, CYP2B1, and CYP2B2 in the liver. A relatively long duration of DPH administration (8 d and 16 d) resulted in abolition of the induction of hepatic CYP but increased CYP3A activities were maintained. These results suggest that the duration of DPH administration could be an important determinant of hepatic CYP induction.     

Differential Activities of CYP1A Isozymes in Hepatic and Intestinal Microsomes of Control and 3‐Methylcholanthrene‐Induced Rats

Abstract: Differences in expression of CYP1A isoforms (CYP1A1 and CYP1A2) in liver and small intestine of male Wistar rats and their inducibility by 3‐methylcholanthrene as well as the effect of different CYP1A1/1A2 expression on caffeine metabolism were investigated. In rat liver, CYP1A2 is the predominant isoform and CYP1A1 protein expression in liver is significantly increased after treatment by 3‐methylcholanthrene. In contrast, only CYP1A1 was detected in control and 3‐methylcholanthrene induced small intestine microsomes. Treatment with 3‐methylcholanthrene (40 mg/kg intraperitoneally daily during 1, 2, 3 or 4 days) demonstrated that liver CYP1A1 is more sensitive for the induction effects than CYP1A2 and also that significant induction of CYP1A1 in rat small intestine only occurred after 3 to 4 days pretreatment. Caffeine metabolism and inhibition studies by furafylline, CYP1A1 antiserum and ketoconazole revealed that the differences in the expression of CYP1A1 and CYP1A2 in the two tissues led to significant changes in the contribution of the various isoenzymes involved in the biotransformation of caffeine. Whereas in liver paraxanthine formation was almost exclusively catalyzed by CYP1A2, in rat proximal intestine it was formed by CYP1A1. In addition, other CYP enzymes (most probably CYP3A) play a significant role in theobromine and theophylline formation from caffeine in rat intestine. Overall, this study shows different expression and inducibility of CYP1A1/1A2 by 3‐methylcholanthrene in rat liver and small intestine. Furthermore in rat intestine cytochrome P450 isozymes such as CYP1A1 and CYP3A replace CYP1A2 in the caffeine metabolism.     

Cytochrome P450‐mediated metabolism in the human gut wall

Objective Although the human small intestine serves primarily as an absorptive organ for nutrients and water, it also has the ability to metabolise drugs. Interest in the small intestine as a drug‐metabolising organ has been increasing since the realisation that it is probably the most important extrahepatic site of drug biotransformation. Key findings Among the metabolising enzymes present in the small intestinal mucosa, the cytochromes P450 (CYPs) are of particular importance, being responsible for the majority of phase I drug metabolism reactions. Many drug interactions involving induction or inhibition of CYP enzymes, in particular CYP3A, have been proposed to occur substantially at the level of the intestine rather than exclusively within the liver, as originally thought. CYP3A and CYP2C represent the major intestinal CYPs, accounting for approximately 80% and 18%, respectively, of total immunoquantified CYPs. CYP2J2 is also consistently expressed in the human gut wall. In the case of CYP1A1, large interindividual variation in the expression levels has been reported. Data for the intestinal expression of the polymorphic CYP2D6 are conflicting. Several other CYPs, including the common hepatic isoform CYP2E1, are expressed in the human small intestine to only a very low extent, if at all. The distribution of most CYP enzymes is not uniform along the human gastrointestinal tract, being generally higher in the proximal regions of the small intestine. Summary This article reviews the current state of knowledge of CYP enzyme expression in human small intestine, the role of the gut wall in CYP‐mediated metabolism, and how this metabolism limits the bioavailability of orally administered drugs. Possible interactions between drugs and CYP activity in the small intestine are also discussed.     

Development of an optimized procedure for the preparation of rat intestinal microsomes: comparison of hepatic and intestinal microsomal cytochrome P450 enzyme activities in two rat strains

1. The objective of this study was to characterize cytochrome P450 (CYP) activities in both intestinal and hepatic microsomes from Wistar and Sprague–Dawley rats.

2. Specific probes for measuring CYP activities were selected using rat recombinant CYP.

3. The intestinal microsome preparation was optimized getting a more relevant and reproducible abundance of CYPs to measure CYP activities.

4. Testosterone, propranolol, diclofenac, and midazolam were determined as specific substrates of rat CYP2C11, CYP2D2, CYP2C6, and CYP3A, respectively. Ethoxyresorufin and pentoxyresorufin were not specific substrates of CYP1A2 and CYP2B1, respectively. Hepatic and intestinal microsomes expressed active CYP1A1, CYP1A2, CYP2B1, and CYP3A2. Only liver expressed active CYP2C6, CYP2C11, and CYP2D2. Wistar liver expressed more active CYP1A and CYP3A2, but less active CYP2B1 than Wistar intestine. Sprague–Dawley liver expressed more active CYP2B1 and CYP3A2, but less active CYP1A than Sprague–Dawley intestine.

5. In conclusion, CYP activities were qualitatively equivalent but not quantitatively in both strains.

     

抗肿瘤活性物CH330331在大鼠肝微粒体代谢及对药酶影响作用的研究

目的：体外研究大鼠肝微粒体中CH330331代谢的酶促动力学,并利用＂Cocktail＂探针药物模型,研究CH330331对主要CYP450亚型的体外抑制作用。方法：优化CH330331在大鼠肝微粒体中孵育的条件,并进行酶促动力学研究;探讨体外＂Cocktail＂探针药物模型的组成,并研究CH330331对CYP450亚型的体外抑制作用。结果：CH330331代谢的酶促动力学参数：最大反应速率（Vmax）为2.08μmol/（min.mgpro-tein）,米氏常数（Km）为18.96μmol/L。CH330331对大鼠CYP1A2、CYP2C9和CYP2D6有弱抑制作用,对大鼠CYP2C19、CYP2E1和CYP3A4没有抑制作用。结论：临床使用中CH330331可以增加主要通过CYPCYP1A2,CYP2C9和CYP2D6代谢的药物浓度。