RRM2B/Ca2+/CaMKK2调控LdT为代表的核苷类似物致慢乙肝患者CK升高的机制研究

核苷类似物替比夫定（LdT）因e抗原血清学转换率高、改善肾功能等特点在抗乙肝病毒治疗中有一定优势。然而高达70%以上的患者有肌酸激酶（CK）升高的不良反应，因此研究CK升高的机制并找寻有效干预措施对临床安全用药具重要意义。课题组前期研究发现：CK升高组患者的血药浓度显著高于CK正常组，且血药浓度升高与RRM2B基因单核苷酸多态性有关；细胞实验发现LdT浓度增加可激活Ca2+/CaMKK2轴产生氧化应激损伤致CK升高。推测：CK升高可能因RRM2B多态引起LdT血药浓度增高、产生氧化应激损伤所致。本研究拟采用CRISPR/Cas9定点修饰技术构建RRM2B多态性细胞和小鼠模型，研究多态模型下相同剂量LdT给药后的血药浓度、氧化应激、Ca2+/CaMKK2轴及CK的差异，探究CK升高机制。并依此机理设计药物干预方案，为临床安全用药提供依据，亦为其他核苷类似物致CK升高的机理研究提供参考。

Telbivudine (LdT), one of the nucleoside analogue, has some advantages in anti-hepatitis B virus treatment due to the high seroconversion rate of e antigen and the improvement of renal function. However, up to 70% of patients have the side effect of creatine kinase (CK) elevation. Therefore, to study the mechanism of CK elevation and find effective intervention is of great significance to the clinical safety of medication. We found that (i) The Plasma CK concentrations in elevated CK group were significantly higher than CK normal group, RRM2B gene single nucleotide polymorphism（SNPs） have a positive correlation with patients’ plasma concentration and their CK levels. (ii) In vitro experiments showed that high concentrations of LdT could induced the CK elevation as resulted by activating the Ca2+/CaMKK2 axis, caused the oxidative stress damage. Speculation: RRM2B polymorphism caused by increased blood concentration, resulting the oxidative stress damage, leading to elevated CK. This study intends to use CRISPR / Cas9 site-directed modification technology to build RRM2B polymorphic cells and mouse models, To study the difference of plasma concentration, oxidative stress, Ca2 + / CaMKK2 axis and CK after administration of LdT under the same dose in the polymorphic model, And To explore the mechanism of CK elevation. Based on this mechanism, to design a drug intervention program, not only to provide a basis for clinical safety medication, but also provide a reference for the mechanism of other nucleoside analogues caused by CK elevation.