Tobacco smoking and its drug interactions with comedications involving CYP and UGT enzymes and nicotine

Tobacco smoking is a global public health threat causing several illnesses including cardiovascular disease(Myocardial infarction), cerebrovascular disease(Stroke), peripheral vascular disease(Claudication), chronic obstructive pulmonary disease, asthma, reduced female infertility, sexual dysfunction in men, different types of cancer and many other diseases. It has been estimated in 2015 that approximately 1.3 billion people smoke, around the globe. Use of medications among smokers is more common, nowadays. This review is aimed to identify the medications affected by smoking, involving Cytochrome P450(CYP)and uridine diphosphate-glucuronosyltransferases(UGTs) enzymes and Nicotine. Polycyclic aromatic hydrocarbons(PAHs) of tobacco smoke have been associated with the induction of CYP enzymes such as CYP1A1, CYP1A2 and possibly CYP2E1 and UGT enzymes. The drugs metabolized by CYP1A1,CYP1A2, CYP2E1 and UGT enzymes might be affected by tobacco smoking and the smokers taking medications metabolized by those enzymes, may need higher doses due to decreased plasma concentrations through enhanced induction by PAHs of tobacco smoke. The prescribers and the pharmacists are required to be aware of medications affected by tobacco smoking to prevent the toxicityassociated complications during smoking cessation.

嘌呤核苷磷酸化酶/嘧啶核苷磷酸化酶共表达及固定化催化合成阿糖核苷

将嘌呤核苷磷酸化酶(PNP)和尿苷磷酸化酶(UP)进行共表达和双酶固定化,提高生物法合成阿糖核苷过程中底物转化率和催化剂稳定性。首先,构建大肠杆菌内源(PNP)和(UP)过表达工程菌,考察工程菌催化不同阿糖核苷之间转化的效率。将PNP和UP双酶固定化,并对固定化双酶进行回收利用,考察重复使用过程中固定化双酶的催化效率。结果表明:工程菌催化阿糖尿苷和腺嘌呤生成阿糖腺苷的反应最高转化率可达93.6%。固定化双酶催化合成阿糖2,6-二氨基嘌呤核苷的最高转化率可达99.8%。重复回收使用固定化双酶19次后对底物的转化率达到60.6%,累计有效催化时长可达684 h。PNP和UP的双酶耦合体系能高效催化阿糖核苷之间的转化,固定化修饰有利于延长酶的使用寿命,为生物法生产核苷类似物提供重要科学参考。

丹酚酸A对大鼠肝脏尿苷二磷酸葡醛酸转移酶活性的影响

目的考察丹酚酸A(salvianolic acid A,SAA)对大鼠肝脏尿苷二磷酸葡醛酸转移酶(UGTs)的影响。方法SD大鼠48只,雌雄各半,随机分为SAA组、阳性对照组和空白对照组3组。连续给药1周后断头处死动物,分离制备肝组织亚细胞组分,以对硝基酚(4-NP)为探针药物,HPLC法测定各亚细胞组分UGTs活性。结果在不同肝组织亚细胞组分中,以肝微粒体的UGTs酶活性最高,且雄鼠显著高于雌鼠;与空白对照组比较,SAA组大鼠的肝微粒体蛋白浓度和UGTs酶活性均无显著变化,差异无统计学意义(P>0.05)。结论 SAA经静脉途径连续给药1周对SD大鼠肝脏的UGTs酶活性无显著的诱导或抑制作用,提示其在临床应用时发生经UGTs酶介导的药物相互作用的潜在风险较小。

Interactions of drug-metabolizing enzymes with the Chinese herb Psoraleae Fructus

Psoraleae Fructus(the dried fruits of Psoralea corylifolia), one of the most frequently used Chinese herbs in Asian countries, has a variety of biological activities. In clinical settings, Psoraleae Fructus or Psoraleae Fructus-related herbal medicines frequently have been used in combination with a number of therapeutic drugs for the treatment of various human diseases, such as leukoderma, rheumatism and dysentery. The use of Psoraleae Fructus in combination with drugs has aroused concern of the potential risks of herb-drug interactions(HDI) or herb-endobiotic interactions(HEI). This article reviews the interactions between human drug-metabolizing enzymes and the constituents of Psoraleae Fructus;the major constituents in Psoraleae Fructus, along with their chemical structures and metabolic pathways are summarized, and the inhibitory and inductive effects of the constituents in Psoraleae Fructus on human drug-metabolizing enzymes(DMEs), including target enzyme(s), its modulatory potency, and mechanisms of action are presented. Collectively, this review summarizes current knowledge of the interactions between the Chinese herb Psoraleae Fructus and therapeutic drugs in an effort to facilitate its rational use in clinical settings, and especially to avoid the potential risks of HDI or HEI through human DMEs.

CYP450、GSTs、UGT基因多态性与抗结核药物肝损伤的关系

目的探讨细胞色素P450(CYP450)、谷胱甘肽转移酶(GSTs)、尿苷二磷酸葡萄糖醛酸转移酶(UGT)基因多态性及其交互作用与抗结核药物性肝损伤(ADLI)发生的关系。方法选择接受抗结核化疗6个月内出现肝损伤的汉族结核病患者207例纳入病例组,以同期治疗中未出现肝功能异常的结核病患者207例为对照组。采用聚合酶链反应-限制性片段长度多态性法观察CYP1A2 734C/A、CYP3A4 18B-20232G/A、CYP3A5 3-6986A/G、CYP2C19 681G/A、GSTA1-69C/T、GSTM3缺失突变、UGT2B7-268A/G、UGT2B7 802C/T位点的多态性。采用单因素、多因素Logistics回归分析法分析CYP450、GSTs、UGT基因多态性与ADLI发生的关系。采用多因子降维法分析CYP450、GSTs、UGT基因多态性位点之间的交互作用与ADLI发生的关系。结果 CYP1A2 734C/A的AA基因型、CYP3A4 18B-20232G/A的GA基因型、UGT2B7-268A/G的AG基因型、UGT2B7 802C/T的TT基因型是ADLI的保护基因型,而CYP3A5 3-6986A/G的AG及GG基因型、GSTA1-69C/T的TT基因型则是ADLI的危险基因型。调整其他基因多态性的影响后,发现CYP3A4*18B-20232G/A、CYP3A5*3-6986A/G、UGT2B7-268A/G和UGT2B7802C/T位点基因多态性与ADLI的发生有关。多因子降维法分析得到UGT2B7-268A/G、CYP3A4 18B-20232G、CYP3A5 3-6986G组成的3因素模型为最佳模型,检验样本准确度为61.29%,交叉验证一致性为10/10。最佳模型的估计结果显示,与低危基因型组合相比,高危基因型组合显著增加ADLI的发病风险。结论 CYP3A4*18B-20232G/A、CYP3A5*3-6986A/G、UGT2B7-268A/G、UGT2B7 802C/T位点基因多态性与ADLI的发生有关,且基因位点之间存在交互作用,其中UGT2B7-268A/G、CYP3A4 18B-20232G、CYP3A5 3-6986G组合将显著增加ADLI的发生风险。

Human liver stem/progenitor cells decrease serum bilirubin in hyperbilirubinemic Gunn rat

AIM: To test the ability of adult-derived human liver stem/progenitor cells (ADHLSC) from large scale cultures to conjugate bilirubin in vitro and in bilirubin conjugation deficient rat.

尿苷二磷酸葡萄糖醛酸转移酶1A1基因多态性的表达研究进展

尿苷二磷酸葡萄糖醛酸转移酶1A1(UGT1A1)基因突变可影响UGT1A1的表达及其酶活性,使胆红素代谢减慢,导致高未结合胆红素血症。随着分子生物学技术的发展,越来越多的研究通过分析UGT1A1基因多态性的表达情况及酶活性来明确这些多态性的致病机制。现就UGT1A1基因多态性的表达研究进展进行综述。

UGT1A6单核苷酸多态性与缺血性卒中患者阿司匹林低反应性的关联性研究

目的研究UGT1A6单核苷酸多态性（SNPs）与阿司匹林反应性的关系。方法连续纳入2011年9月至2014年10月在南京卒中注册系统注册的缺血性卒中患者。运用血栓弹力图检测所有入组患者血小板功能，采用改进的多重连接酶反应技术检测患者基因型。采用广义线性模型分析SNPs与阿司匹林反应性之间的相关性。结果共纳入323例缺血性卒中患者，广义线性模型分析发现，rs2070959的显性模型（p=0．084，P=0．010，P校正=0．029）和加性模型（β=0．060，P=0．033）都与血小板抑制率呈显著的正相关。男性患者中，显性模型β=0．098，P=0．006，P校正=0．01；加性模型β=0．072，P=0．024。表明显性模型中，该位点的野生型个体（AA）较含突变基因的个体（GA、GG）发生阿司匹林低反应性的风险更高。结论UGT1A6基因rs2070959位点基因多态性与缺血性卒中患者阿司匹林低反应性相关，其野生型患者（AA）较含突变基因的患者（GA、GG）发生阿司匹林低反应性的风险增高，这种关系在男性患者中尤为显著。因此检测与阿司匹林代谢相关的基因多态性或实验室检测血小板功能可能有助于临床医师为缺血性卒中患者制定个体化抗血小板治疗方案。

甜橙中UDP-鼠李糖合成酶基因CsRHM的克隆与鉴定

UDP-鼠李糖是一种由鼠李糖合成酶(rhamnose synthase,RHM)催化合成的糖苷供体,是合成各种鼠李糖糖苷类次生代谢产物的重要组成之一。该研究从甜橙中首次克隆得到一个RHM基因(CsRHM),并进行生物学信息分析,体外功能鉴定等特异性分析。结果显示CsRHM的开放阅读框为2007 bp,编码668个氨基酸,推测相对分子质量为75.27 kDa,理论等电点为6.97,具有RHM酶家族的特征信号序列(GxxGxxG/A和YxxxK)。多序列对比与系统进化树显示,CsRHM与其他物种的RHM具有同源性。体外酶促反应结果证实CsRHM重组蛋白具有将UDP-葡萄糖转化为UDP-鼠李糖的催化活性,并且明确了其催化的酶动力学参数V_(max)=0.3737μmol·L^(-1)·min^(-1),K_(m)=21.29μmol·L^(-1),K_(cat)=0.24 s^(-1),K_(cat)/K_(m)=1.13×10^(4)s^(-1)·L·mol^(-1)。该研究首次报道了CsRHM,并验证了其体外催化功能,为进一步研究生物合成UDP-鼠李糖奠定基础。

乙酰短杆菌中核苷磷酸化酶的性质研究

以乙酰短杆菌完整细胞为酶源,研究不同条件下核苷磷酸化酶的性质。方法:将乙酰短杆菌湿菌体置于不同保藏温度及在不同种类缓冲溶液中考察其稳定性;在有或无核保护下核苷磷酸化酶对热的稳定性;并设计核苷的磷酸解反应或合成反应,测定核苷磷酸化酶的活力及酶促反应的表观米氏常数。结果:乙酰短杆菌中的核苷磷酸化酶经低温保藏可以保持较长时间的稳定性;菌体在60℃处理1小时即失去核苷磷酸化酶的活力,但是添加胸腺嘧啶有明显的保护作用;菌体中核苷磷酸化酶的合成能力明显大于磷酸解能力;对尿苷和5-甲基尿苷的表观米氏常数和最大反应速率分别为16.7、11.4 mmol/L,0.0063、0.0041 mmol/L.min。结论:含核苷磷酸化酶的乙酰短杆菌完整细胞作为酶源,在低温下可以长时间保藏,反应中的碱基对核苷磷酸化酶的抗热性有益,该菌种可以作为工业上核苷磷酸化酶的来源。

固定化尿苷-胞苷激酶和聚磷酸激酶偶联催化制备5′-胞苷酸

尿苷-胞苷激酶作为生物体核苷酸代谢补偿途径中的重要催化剂,可以催化胞苷的磷酸化反应合成5′-胞苷酸(简称胞苷酸),但需要NTP作为磷酸供体。为了提高胞苷酸的生产效率,文中首先使用大肠杆菌分别异源表达来源于嗜热栖热菌Thermus thermophiles HB8的尿苷-胞苷激酶和来源于类球红细菌Rhodobacter sphaeroides的聚磷酸激酶,其中尿苷-胞苷激酶用于催化胞苷和ATP形成胞苷酸,聚磷酸激酶则用于ATP的循环再生。然后,使用D403金属螯合树脂吸附Ni^2+形成固定化载体,再利用固定化载体特异性吸附重组酶形成固定化酶。最后,单因素优化实验确定固定化酶的催化反应条件,在30℃、pH 8.0的条件下,以60 mmol/L胞苷和0.5 mmol/L ATP为底物,可实现5批次的高效连续催化反应,胞苷酸平均摩尔得率达到91.2%。上述制备方法反应成本低,产物得率高,酶利用率高,在工业生产中具有较好的应用潜力。

Inhibitory potential of three Yin-tonification herbal formulas on the activities of human major cytochrome P450 and UDP-glucuronosyltransferases isozymes in vitro

OBJECTIVE:To investigate the influence of Yin-tonification herbal formulas Jaeumganghwa-tang(Ziyin Jianghuo Tang,JEGHT),Ssanghwa-tang(Shuanghe Tang,SHT) and Yukmijihwang-tang(Liuwei Di huang Tang,YMJHT) on the activities of human major cytochrome P450(CYP450 s) and UDP-glucuronosyltransferases isozymes(UGTs) in vitro.METHODS:The activities of CYP450 s(CYP1 A2,CYP3 A4,CYP2 B6,CYP2 C9,CYP2 C19,CYP2 D6 and CYP2 E1) and UGTs(UGT1 A1,UGT1 A4 and UGT2 B7)were assessed using in vitro fluorescence-and luminescence-based enzyme assays,respectively.The effects of herbal formulas on the activities of CYP450 s and UGTs were presented as IC50 values.RESULTS:JEGHT showed the potent inhibition of the CYP2 D6 activity,with weak inhibition on the activities of CYP1 A2,CYP2 B6,CYP2 C9,CYP2 C19,CYP2 E1,CYP3 A4,UGT1 A1,UGT1 A4 and UGT2 B7.SHT inhibited the activities of CYP1 A2 and CYP2 E1,whereas the negligible inhibition of the activities of CYP2 B6,CYP2 C9,CYP2 C19,CYP2 D6,CYP3 A4,UGT1 A1,UGT1 A4 and UGT2 B7 through SHT was observed.YMJHT inhibited CYP2 E1 activity,with a negligible inhibition on the activities of CYP1 A2,CYP2 B6,CYP2 C9,CYP2 C19,CYP2 D6,CYP3 A4,UGT1 A1,UGT1 A4 and UGT2 B7.CONCLUSION:These findings provide information about the potential interactions between three Yin-tonification herbal formulas and conventional drugs.