左旋氧氟沙星对大鼠肝重 肝微粒体蛋白质及细胞色素P450的影响

目的 研究和比较不同剂量给予左旋氧氟沙星后对大鼠肝重、肝微粒体蛋白质及细胞色素P450含量的影响.方法 将大鼠分成空白对照组和给药组.采用连续给予不同剂量左旋氧氟沙星后,测定大鼠的肝重、肝微粒体蛋白质及细胞色素P450含量.给药方案为每组80、160、240mg@kg-1,腹腔注射给药,qd,连续给药7d.结果 研究结果显示,给予不同剂量的左旋氧氟沙星后,大鼠的肝重及细胞色素P450含量均明显降低,中剂量组及高剂量组分别与对照组及低剂量组比较有极显著性差异(P<0.01).微粒体蛋白质含量各组间比较无差异(P>0.05).结论 左旋氧氟沙星的这种作用可能引起肝药酶对某些药物代谢的改变.     

氟喹诺酮类药物对大鼠肝微粒体细胞色素P450酶系的影响

目的比较4种氟喹诺酮类药物[左氧氟沙星(LVFX)、加替沙星(GTFX)、莫西沙星(MXFX)、帕珠沙星(PZFX)]对大鼠肝微粒体细胞色素P450(CYP450)酶系的影响。方法 30只雄性Wistar大鼠随机分为空白对照组、LVFX组(LV组)、GTFX组(GT组)、MXFX组(MX组)、PZFX组(PZ组),每组6只,给药方案为120mg/(kg.d),尾静脉注射给药,连续7d。末次给药后24h处死动物,差速离心法制备肝微粒体混悬液,Lowry法测定肝微粒体蛋白浓度,分光光度法检测肝微粒体CYP450酶系的含量及活性,并采用单因素方差分析进行统计。结果与空白对照组比较,MX组和GT组大鼠肝重明显降低(P<0.01,P<0.05),LV组、GT组和MX组大鼠肝微粒体蛋白浓度明显增加(P<0.01),LV组和GT组CYP450含量增加(P<0.05,P<0.01),GT组细胞色素b5(Cytb5)含量增加(P<0.05)。肝微粒体NADPH-CytC还原酶活性测定结果显示,给药组与空白对照组差异无统计学意义(P>0.05)。氨基吡啉-N-脱甲基酶活性测定结果显示,LV组、GT组和MX组酶活性与空白对照组比较差异均有统计学意义(P<0.01)。红霉素-N-脱甲基酶活性测定结果显示,与空白对照组比较,GT组酶活性降低,MX组酶活性升高,差异有统计学意义(P<0.01)。大鼠肝微粒体CYP450酶系亚家族活性检测结果显示,与空白对照组比较,LV组、MX组和PZ组7-苄基香豆素脱烃酶(BROD)活性升高(P<0.01),GT组7-甲氧基香豆素脱烃酶(MROD)活性降低(P<0.05)、7-苯基香豆素脱烃酶(PROD)活性增加,PZ组PROD活性降低(P<0.01),4种药物均可使乙氧基香豆素脱烃酶(EROD)活性增加(P<0.01)。结论 4种氟喹诺酮类药物对CYP450酶系均有肯定作用,对不同的酶其作用效果不同,从影响范围来看,GTFX、MXFX、LVFX和PZFX的作用依次减小。     

甲磺酸加替沙星对大鼠肝微粒体细胞色素P450酶系的影响

目的研究甲磺酸加替沙星对大鼠肝微粒体细胞色素P450酶系的影响。方法将Wistar大鼠分为空白对照组、甲磺酸加替沙星高、中、低剂量组（240、160、80mg·kg^-1）,ip,qd,共7d。采用差速离心法制备大鼠肝微粒体;BAC法测定蛋白浓度;分光光度法检测肝微粒体细胞色素P450酶含量及活性;单因素方差分析进行统计。结果给药组大鼠的肝重、微粒体细胞色素P450含量均明显降低,细胞色素b5的含量增高,但增高的趋势随剂量增加有所抑制;对NADPH-Cytc还原酶的影响：低、中剂量组与对照组比较有显著性差异（P〈0.01）,高剂量组与对照组比较无显著性差异（P〉0.05）,组间比较有显著性差异（P〈0.05）;对氨基比林-N-脱甲基酶和红霉素-N-脱甲基酶的影响：给药组与对照组比较有显著性差异（P〈0.01）,组间比较也有显著性差异（P〈0.05,P〈0.01）。另外,在中、高剂量组大鼠出现肝硬度增加、腹水等现象。结论甲磺酸加替沙星对大鼠肝微粒体细胞色素P450酶具有一定的影响,对NADPH-Cytc还原酶有诱导作用,对氨基吡啉-N-脱甲基酶和红霉素-N-脱甲基酶有抑制作用。可能引起肝药酶对某些药物代谢的改变。     

中药对细胞色素P450诱导或抑制作用的影响因素

本文通过查阅近年来国内外有关中草药对CYP450影响的文献，并加以归纳、总结，综述了能够影响中药对CYP450诱导或抑制作用的各种药物因素和其他因素，从而指导和促进中草药对CYP450影响的研究。     

1,5-二咖啡酰奎宁酸对大鼠肝微粒体细胞色素P450含量的影响

1,5-二咖啡酰奎宁酸(1,5-d icaffeoylqu in ic ac id,1,5-DC-QA)是我国近期自主研发的拟申报治疗艾滋病(acqu ired im-mune defic iency syndrom e,AIDS)的一类创新新药(药品注册管理办法,注册分类1),它为首次合成的全新化合物,其抑制人类免疫缺陷病毒(hum an immunodefic ienc     

1，5-二咖啡酰奎宁酸对大鼠所微粒体细胞色素P450含量的影响

1，5-二咖啡酰奎宁酸（1,5-dicaffeoylquini cacid，1，5-DCQA）是我国近期自主研发的拟申报治疗艾滋病（acquired immune deficiency syndrome，AIDS）的一类创新新药（药品注册管理办法，注册分类1），它为首次合成的全新化合物，其抑制人类免疫缺陷病毒（human immunodeficiency virus，HIV）的作用已经在细胞与整体动物等多种实验模型上得到证实。研究表明它的作用靶点为HIV-1整合酶，该酶是介导HIV基因组进入宿主染色体的一个关键性的酶。毒理学实验表明该药的毒性较低，提示该化合物为有独特作用特点的、毒副反应小的潜在新药。     

氟喹诺酮类药物在人肝微粒体对环孢霉素A代谢影响的研究

目的　研究 1 0种氟喹诺酮类药物对环孢霉素A代谢的影响。方法　采用人肝微粒体酶体外代谢试验 ,用荧光偏振免疫法测定环孢霉素A的浓度。结果　诺氟沙星、氧氟沙星、左氧沙星 ,司帕沙星、洛美沙星、培氟沙星和环丙沙星对环孢霉素A的代谢具有显著抑制作用 (P <0 .0 5 ) ;氟罗沙星、芦氟沙星和依诺沙星在相应浓度下未见对环孢霉素A的显著抑制。其抑制程度依次为 :洛美沙星 >氧氟沙星 >司帕沙星 >左氧沙星 >环丙沙星 >培氟沙星 >诺氟沙星 >氟罗沙星 >依诺沙星 >芦氟沙星。本体外试验数据与临床结果并不完全相关。结论　本试验结果提示某些氟喹诺酮药物对人细胞色素P450 中CsA代谢酶具有潜在的选择性抑制作用     

细胞色素P—450与电离辐射的关系

电离辐射可以改变细胞色素P-450(主要有CYP1Bl、CYPlAl、CYP4All、CYP2E1等)的活性和(或)mRNA、蛋白含量，从而影响药物代谢和有毒化学物的生物转化过程及其生物学作用。细胞色素P—450参与了生物还原活性物TMQ、AQ4N在机体内的还原。动物实验和已有的临床研究表明，调节P-450可以提高生物还原活性物的辐射增敏作用和抗肿瘤作用。     

黄芩甙对小鼠肝细胞色素P450及其亚家族的诱导

目的：观察黄芩甙对小鼠肝细胞色素Ｐ４５０及其亚家族的影响,深入探讨黄芩甙保肝作用的机理。方法：采用分光光度法分别测定小鼠肝微粒体细胞色素Ｐ４５０、ｂ５含量及氨基比林Ｎ－脱甲基酶（ＡＤＭ）、７－乙氧基香豆素Ｏ－脱乙基酶（ＥＣＤ）、苯并芘羟化酶（ＡＨＨ）。采用蛋白印迹杂交技术鉴定细胞色素Ｐ４５０同功酶。结果：给小鼠黄芩甙（１００ｍｇ．ｋｇ＾－１．ｄ＾－１）灌胃,连续７ｄ,可使小鼠肝微粒体细胞色素Ｐ４５     

复方丹参滴丸对大鼠肝CYP450酶系诱导作用的研究

目的观察复方丹参滴丸诱导处理对大鼠肝细胞色素P450及其主要亚型的影响.方法 Wistar大鼠用125、750、4 500mg*kg-1*d-1复方丹参滴丸连续灌胃诱导处理5d,测定微粒体中总CYP450含量和CYP1A2、2B1/2、2E1和3A亚型活性.结果不同剂量复方丹参滴丸诱导处理后大鼠肝脏脏器系数、总CYP450含量及CYP1A2、2E1、3A亚型活性未见明显增高.高剂量复方丹参滴丸诱导后,大鼠肝脏CYP2B1/2活性与空白对照组相比有显著升高(P<0.05),中、低剂量组CYP2B1/2活性未见明显升高.相应的阳性对照剂均导致肝脏CYP450及其亚型活性明显升高.结论复方丹参滴丸对大鼠肝脏CYP450及主要亚型CYP1A2、2E1、3A无诱导效应,高剂量下仅对CYP2B1/2有轻度诱导效应,此种作用无明显临床意义.     

Prodrug-activating Gene Therapy with Rabbit Cytochrome P450 4B1/4-Ipomeanol or 2-Aminoanthracene System in Glioma Cells

Objective

We determined the cytotoxic properties of cytochrome P450 4B1 (CYP4B1) activated 4-ipomeanol (4-ipo) and 2-aminoanthracene (2-AA) in rat glioma to verify the CYP4B1/4-ipo or 2-AA system for prodrug-activating gene therapy.

Methods

The cyp4B1 cDNA was cloned into pcDNA3.1/Hygro from rabbit lung total RNA (pcDNA-cyp4B1). Lentiviral vector encoding firefly luciferase (fLuc) was infected into C6 (rat glioma), and the fLuc-expressing cell was selected (C6-L). After transfection with pcDNA-cyp4B1 vector into C6-L, the single clone expressing cyp4B1 gene was selected (C6-CL). Prodrug for various concentrations of 4-ipo or 2-AA was treated for 72 h and 96 h. The cell survival rate of C6-CL was determined using MTT assay and trypan-blue dye exclusion methods.

Results

By RT-PCR analysis, fLuc and CYP4B1 expression was detected in C6-CL, but not in C6. MTT assay and trypan-blue dye exclusion showed that IC₅₀ of C6-CL was 0.3 mM and <0.01 mM after 4-ipo or 2-AA treatment at 96 h or 72 h exposure, respectively. Cell survivals of C6-CL were more rapidly reduced after treatment with 4-ipo or 2-AA than those of C6-L cells. The cell survival rate with MTT and trypan-blue dye exclusion assay was well correlated with fLuc activity in C6-CL cells.

Conclusion

CYP4B1-based prodrug-activating gene therapy may have the potential to treat glioma and the cytotoxic effects of CYP4B1 enzyme activated 4-ipo or 2-AA in C6, and could be clearly determined by bioluminescent activity in C6-CL.     

The relevance of cytochrome P450 polymorphism in forensic medicine and akathisia-related violence and suicide

Adverse drug reactions and interactions are among the major causes of death in the United States. Antidepressants have been reported as causing suicide and homicide and share the class attribute of frequently producing akathisia, a state of severe restlessness associated with thoughts of death and violence. Medical examiners can now identify some pharmacogenetic interactions that cause drugs, deemed safe for most, to be lethal to others. Such deaths do not yet include medication-induced, akathisia-related suicides and homicides. An extrapyramidal side effect, akathisia is a manifestation of drug toxicity whose causes lie, inter alia, in drugs, doses, and co-prescribed medications that inhibit and compete for metabolizing enzymes, which may themselves be defective. In this paper, we report our investigation into adverse drug reactions/interactions in three persons who committed homicide, two also intending suicide, while on antidepressants prescribed for stressful life events. Their histories of medication use, adverse reactions and reasons for changes in medications are presented. DNA samples were screened for variants in the cytochrome P450 gene family; that produce drug metabolizing enzymes. All three cases exhibit genotype-based diminished metabolic capability that, in combination with their enzyme inhibiting/competing medications, decreased metabolism further and are the likely cause of these catastrophic events.     

耐力训练和益气补肾中药对睾酮合成的调节因素--StAR蛋白和P450SCC酶mRNA表达的影响

目的:探讨运动训练和益气补肾中药对影响睾酮合成的StAR蛋白和P450SCC酶的作用.方法:50只雄性Wistar大鼠随机分为安静对照组(n=10)、安静服药组(n=10)、耐力训练组(n=15)和训练服药组(n=15).经6周递增负荷游泳训练后,采用放免法测定大鼠血清睾酮水平,利用RT-PCR方法检测大鼠睾丸StAR和P450SCC mRNA的表达水平.结果:(1)训练组大鼠血清睾酮水平显著降低,而训练服药组大鼠的血清睾酮水平则未降低.(2)未服药训练大鼠的StAR mRNA水平比安静对照组明显下降(P<0.01);服用中药的安静大鼠和运动大鼠的StAR mRNA表达比安静对照组和训练组显著增强(P均小于0.001).(3)训练组和训练服药组大鼠P450SCC mRNA水平均显著低于安静对照组和安静服药组(P<0.05).结论:(1)研究结果提示长期大负荷训练后大鼠睾丸间质细胞StAR mRNA表达下降,益气补肾中药对StAR mRNA的表达转录水平有增强作用.长期大负荷运动造成的血清睾酮水平下降与StAR mRNA的表达强弱有关.(2)长期大负荷运动可造成大鼠睾酮合成限速酶P450SCC mRNA表达降低,益气补肾中药可维持血清睾酮水平,但其在mRNA水平对P450SCC的表达无明显效应,其对睾酮合成酶的影响仍需进一步探讨.     

人参与藜芦合用对CYP1A酶活性的影响

目的研究中药十八反中人参,藜芦合用对CYP1A酶活性的影响,发现基于CYP1A酶活性变化的两者配伍禁忌机制。方法采用高效液相色谱法对人参,藜芦合用对CYP1A酶活性影响进行测定。结果人参与藜芦作用后,大鼠肝微粒体CYP1A的活性呈上升趋势。人参高剂量组、低剂量合用组、藜芦低、高剂量组、高剂量合用组的CYP1A活性上升与空白组比较存在显著性差异（P〈0.05）,低剂量合用组CYP1A活性发生了极为显著的上升（P〈0.01）。结论人参与藜芦配伍前后对CYP1A亚型酶活性调控作用发生明显变化,可能存在基于CYP1A的相反作用,需进一步结合代谢研究加以综合分析,阐明相反作用的机理。     

In vivo study on the roles of cytochrome P450 enzymes for metabolism of 3,4-methylenedioxymethamphetamine (Ecstasy) in rats

Some major metabolic pathways of 3,4-methylenedioxymethamphetamine (MDMA) have been shown to be dependent on cytochrome P450 (CYP) isozymes by in vitro studies. The aim of this study was to clarify the roles of these CYP enzymes for in vivo metabolism of MDMA with respect to two pathways using rats: N-demethylation of MDMA to 3,4-methylenedioxyamphetamine (MDA) and O-demethylenation of MDMA to 3,4-dihydroxymethamphetamine (HHMA)followed by O-methylation to 4-hydroxy-3-methoxymethamphetamine (HMMA). Rats were pretreated with phenobarbital (PB, 80 mg/kg i.p.) or β-naphthoflavone (BNF, 80 mg/kg i.p.) once a day for 3 days before administration of MDMA (10 mg/kg i.p.). Metabolic changes were monitored by measuring the urinary excretion of MDMA and its metabolites. Twenty-four hours after MDMA administration, MDA in rat urine was significantly decreased by 43% and 70%, and HMMA was significantly increased by 33% and 64% in urine samples from PB-pretreated and BNF-pretreated rats, respectively, as compared with the control values. Testosterone 6β-hydroxylase (CYP3A), pentoxyresorufin O-dealkylase (CYP2B1), ethoxyresorufin O-deethylase (CYP1A1), and methoxyresorufin O-demethylase (CYP1A2) activities were increased 2–6 fold in both PB-pretreated and BNF-pretreated rat liver microsomes sampled at 24 h after MDMA administration as compared with the control values. These results suggest that PB-induced and BNF-induced CYP enzymes have inhibitory effects on N-demethylation of MDMA to MDA in vivo in rats. If HHMA is the precursor of HMMA in rats, there is a possibility that the O-demethylenation of MDMA to HHMA is increased by the induced CYP enzymes. The decreased urinary concentration of MDMA and very low percent recoveries of MDA, HMMA, and (4-hydroxy-3-methoxyphenyl)acetone (HMPA) in the inducer-pretreated groups suggest that other metabolic pathways of MDMA exist and are activated under the present experimental conditions.     

围生期双酚A暴露对断乳期雄性子代脑芳香化酶表达的影响

目的：研究围生期双酚A暴露对断乳期雄性子代大鼠脑中芳香化酶P450（P450arom）表达的影响，探索双酚A影响脑发育的机制。方法：对母鼠从妊娠第11d直至产后断乳期（即出生后第21d，postnatal day 21，PND21）给予双酚A（Bisphenot A，BPA）2，20，100mg／kg。各组在断乳期PND21取雄性子代大鼠断头处死，迅速取脑组织进行免疫组织化学染色检测P450arom表达。结果：免疫组织化学染色结果显示，P450arom在大鼠海马和大脑皮层都有表达；对结果进行灰度值分析显示，高剂量组和中剂量组雄性子代大鼠断乳期P450arom在海马CA3区表达的灰度值分别为143．43和130．76，与对照组179．4612比较，有统计学意义；高剂量组雄性子代大脑皮层P450arom的灰度值为185．21，与对照组196．88比较，有统计学意义。结论：围生期暴露于BPA可使断乳期雄性子代脑中P450arom蛋白表达增加，这可能是影响发育机制的途径之一。