【作者】 赵洋；

【导师】 李建新；

【作者基本信息】 南京大学 ， 化学工程（专业学位）， 2016， 硕士

【摘要】 药物代谢动力学(Pharmacokineties,PK)是药理学的一个重要组成部分,是应用动力学原理研究药物在机体中吸收、分布、代谢、排泄的时间过程。理想的候选化合物不仅需要较强的药理活性,还必须有适宜的作用时间和良好的生物利用度。在新药的研制过程中,候补分子的药物代谢和动力学特行极其重要。骨质疏松是一种全身骨代谢障碍疾病,被形象地称为沉默的杀手,是老龄社会的重大问题。市场上抗骨质疏松的药物主要分为两大类:抑制骨吸收和促进骨形成。目前临床以抑制骨吸收类药物为主,主要为双膦酸盐。遗憾的是目前具有促进骨形成作用的临床药物只有一个,甲状旁腺素(PTH1-34),而且有给药期限限制及较大的副作用。因此,开发新的抗骨质疏松药物具有重大意义。齐墩果酸具有广泛生物活性,课题组前期合成了系列的齐墩果酸衍生物,并发现其中的一个衍生物K显示体内外抗骨质疏松活性。为了了解K的成药性,本文对该化合物的大鼠体内的药代动力学特性及其组织分布进行了研究。一、化合物K在大鼠体内血药浓度的测定及其药代动力学建立了测定SD大鼠血浆中K浓度的灵敏、快速的LC-MS/MS测定方法,探讨K在大鼠体内的药代动力学。血浆样品加入内标8aIS后,经过甲醇沉淀蛋白,高速离心,取上层清液进行LC-MS/MS分析。采用的色谱柱为Xbridge C18(2.1mm × 50mm,2.5μm),流动相为0.1%甲酸乙腈-0.02%甲酸水梯度洗脱,流速为0.5mL/min,柱温为40℃。质谱采用ESI离子源,多反应检测模式(MRM)进行正离子检测,K和内标8aIS的选择性检测离子分别为m/z 821.437→203.200和m/z 582.271→409.300。结果表明K的线性良好,方法灵敏、快速、专属性强,方法学考察符合相关要求,可以用于K在大鼠体内的药代动力学研究。SD大鼠,每组为6只,静脉以及灌胃给药后,测定给药后不同时间的血药浓度,利用DAS软件计算其药代动力学参数。SD大鼠灌胃给药组剂量为10mg/kg,得到的血药浓度-时间曲线经过非房室模型拟合后,半衰期T1/2为2.42±0.39h,达峰时间为3.2±0.84h,曲线下面积AUC为180.33 ± 40.47μg/L*h。SD大鼠静脉注射给药组剂量为1mg/kg,血药浓度-时间曲线经过二房室模型拟合后,分布半衰期t1/2α为0.04±0.01h,消除半衰期t1/2β为1.46±0.19h,曲线下面积AUC为4306.61±546.41μg/L*h。最终得到化合物K在大鼠体内的生物利用度为0.419%。二、K在大鼠体内的组织分布研究建立了 UFLC-MS/MS的方法,测定K在雄性大鼠八个脏器(心、肝、脾、肾、胃、空肠、肌肉、脂肪)3个时间点(1h、3h、10h)的含量,进行了组织器官分布研究。K在SD大鼠空肠和胃中分布较多,其余组织中分布较少且较为均匀。大部分组织中,给药后1h时K的含量最高,在给药10h时,能够检测到的K含量非常低,说明其在体内分布较为迅速,且无蓄积。在除去肠胃的各组织中,心和脾组织中的含量较多,说明K优先分布于血流丰富的组织;而同时肝脏中含量较少,说明K能够很快被肝脏代谢。值得注意的是,K在肌肉组织中的含量多于其他组织,提示其对骨质疏松症的治疗作用可能与肌肉与骨的某种相互作用有关。更多还原

【Abstract】 Pharmacokinetic(Pharmacokineties,PK)is an important part of pharmacology,which studies the drug absorption,distribution,metabolism and excretion(ADME)in organism within a time process.The ideal drug candidates need not only strong pharmacological activities but also the effect of the appropriate action time and good bioavailability.In the process of the development of new drugs,the pharmacodynamics of candidate molecule is extremely important.Osteoporosis is a kind of systemic metabolic bone disorder,which is called a silent killer and is a major problem of aging society.Osteoporosis drugs available in current market are mainly divided into two categories:anti-resorptive and bone anabolic agents.Bisphosphonates is the main representative of anti-resorptive drugs in clinic.PTH 1-34 is the only clinically available bone anabolic drug for the treatment of osteoporosis,while,with dosing period limitation and side effects.Hence,development of anabolic agents for improving bone formation and bone repair has considerable social and economic impact.Oleanolic acid(OA)has extensive biological activity,our group have synthesized novel series of OA derivatives.Among the derivatives,a compound named K displayed a potent inhibitory effect on osteoporosis in vitro and in vivo.In this article,to understand the drugability of K,the pharmacokinetics and tissue distribution of K in rats are studied.1.Determination of K in rat plasma and pharmacokineties study of K in ratsTo establish a simple and sensitive method for quantification of K by LC-MS/MS and study the pharmacokineties of K in rats,K,and 8aIS as an internal standard(IS)in rat plasma samples were extracted by methanol and analyzed by LC-MS/MS after centrifugation.Methods:samples were analyzed with a gradient mobile phase system at a flow-rate of 0.5 mL/min on a Xbridge C18 column(2.1mm×50mm,2.5μm).Measurement of K was performed by positive ion electro spray ionization in multiple reaction monitoring mode,monitoring the transitions m/z 821.437→203.20 and m/z 582.271→409.300 for K and 8aIS,respectively.Results demonstrated that the linearity,sensitivity,specificity and so on met the requirements of biological samples analysis.Therefore,the developed method was applied to the current PK study.The rats were divided into groups and 6 rats per group.After oral administration of K(10mg/kg)to rats,the plasma drug concentration-curve analyzed by non-compartment model.The half-life was 2.415±0.391h.The Tmax was 3.2±0.837h.The AUC(0-t)was 180.33 ± 40.47μg/L*h.After intravenous administration of K(lmg/kg)to rats,the plasma drug concentration-curve analyzed by two-compartmental model.The distribution half-life time was 0.04 ± 0.008h,the elimination half-life time was 1.46±0.189h.The AUC(0-t)was 4306.61 ± 546.41μg/L*h.2.Tissue distribution study on KA method for the determination of K in rat tissues was developed using ultra-fast liquid chromatography-tandem mass spectrometry(UFLC-MS/MS).Eight tissues including heart,liver,spleen,kidney,stomach,jejunum,muscle and fat were measured at 3 different time points(1,3 and 10h).After administration of K,the jejunum and stomach had higher concentration than any other tissues.In most tissues,the concentration of K was the highest in each group at the time of 1h,while at 10h,K can be hardly found in the tissues.It shows that K can be rapidly spread and eliminated.The heart and spleen received more drug than other tissues,implied that K has a priority distribution in the organs of abundant blood flow.On the other hand,we found less K in liver that suggested a quick metabolism by liver.It is worth mentioning that the concentration in muscle was much more than those in others,which suggested there might be a certain interaction between muscle and bone.更多还原