多基因及miRNA"网络"调控下丙戊酸个体化用药研究

Epilepsy is one of the most common forms of nervous system diseases. Valproic acid (2-propylpentanoic acid, VPA) is the first-line agent for epilepsy, but VPA treatment is challenging due to its narrow therapeutic index and marked inter-individual variation in drug response. Therapeutic drug monitoring (TDM), to some extent, can be the instruction for clinical treatment, but the hysteretic nature of TDM limit its application in the adjustment of dosage regimen. The study carried out in our lab in the past 3 years focusing on the interviriability in epileptic patients treated with VPA showed that genetic polymorphisms in the metabolic enzymes involved accounted for only 25% of the inter-individual pharmacokinetic variation. Network pharmacology prompted us to confirme that the mechanism of inter-individual variation in drug response could be explained extensively by "Network". Funded by NSFC (No.30873025), we have explored the effects of genetic polymorphisms in CYP3A4 and in the upstream regulator PXR on the drug metabolism in both cells and volunteers,studied the regulation of different target genes by epigenetic regulators such as mir-148. Based on the previous research，in the present program we are going to thoroughly screen the factors that affect the pharmacokinetics and the pharmacodynamics of VPA by investigating the effect of the more comprehensive genetic mutations in nuclear receptors (PXR/RXR/FXR/CAR etc.) and the blood concentrations of miRNAs predicted by bioinformatic softwares, and the regulatory network comprising of nuclear receptors, metabolic enzymes and transporter, and drug targets (neuropeptide Y and leptin,etc) and associated miRNAs on VPA response, therefore identifying biomarkers with clinical significance, and ultimately developing a dosing algorithm verified by prospecitve clinical trials.

癫痫是神经系统最常见疾病之一，丙戊酸（VPA）是经典抗癫痫药物，但其治疗窗窄、个体差异大困扰着临床用药。虽TDM在一定程度上能指导用药，但其存在显著滞后性。本实验室3年来对癫痫者使用VPA显著个体差异的研究表明，其主要代谢酶遗传多态性只能解释25%的药动学个体差异。网络药理学提示我们必须用"网络"的观念才有可能阐明药物反应个体差异机制。本人已在国家自然基金（30873025）资助下，在细胞及人体水平对CYP3A4及上游调控因子PXR等的基因多态性对药物代谢的影响、表观遗传学水平的调控因子mir-148等对不同靶基因的调控作用进行了研究。本课题将在前期研究基础上，探索更广泛的核受体遗传变异及相关miRNA组成的调控网络对VPA药物反应的影响，结合其药理作用新靶点NPY通路遗传多态性，更全面地筛查与VPA药动学和药效学 相关的影响因素，找出具临床意义的生物标志物，建立剂量预测方程并通过临床验证

丙戊酸（VPA）是经典的一线抗癫痫药物，但其治疗窗窄、个体差异大困扰着临床用药。虽 TDM 在一定程度上能指导用药，但其存在显著滞后性。前期研究发现VPA原形药的浓度并不能很好预测其疗效及毒性，本研究拓展考察了五种代谢产物2-PGA, 3-OH-VPA, 3-keto-VPA, 4-OH-VPA以及4-ene-VPA与VPA药物反应的关系，并从基因组学的角度探索了其药动学差异的影响因素。此外，前期研究表明其主要代谢酶基因多态性仅能解释一部分VPA的药动学个体差异，网络药理学提示我们必须用“网络”的观念才有可能阐明药物反应个体差异机制。本项目系统地研究了众多基因多态性（如转运体，上游调控因子，靶点基因等）及2590种已知的miRNA对 VPA 所致体重增加的的影响，全面筛查了与VPA药动学和药效学相关的影响因素，以期为临床合理应用提供依据。.研究发现：VPA及其五种代谢产物血药浓度在单药治疗组与VPA的疗效无著相关性。基于TOX rs2726599及年龄的多重线性模型，可以解释14.3%的疗效差异。VPA及其代谢产物的浓度与体重增加的发生无关，但本研究率先发现食欲及能量代谢通路的基因对体重增加的影响，提示LEPR及ANKK1基因多态性对预测VPA诱导的体重增加有一定价值；同时我们的研究共筛选出51种与体重增加相关的差异表达miRNAs，进一步为后续的功能验证实验提供理论依据。4-ene-VPA血药浓度升高是肝毒性发生的风险因素，基于年龄、性别以及CPT1A rs2228502的多重线性回归模型可解释14.6%的4-ene-VPA药动学差异，表明该模型能够较有效的预测4-ene-VPA的浓度，并对肝毒性的发生有一定的预测作用。