有机阴离子转运多肽1B1和1B3(OATP1B1/3)作为重要的摄取转运体,在外源性药物和内源性物质向细胞内的转运中起着基础性作用。大鼠OATP1B2,由Slco1b2基因编码,与人OATP1B1/3同源。虽然OATP1B1/3非常重要,很少有动物模型可以用来研究它的特性。在这份报告中,首次利用CRISPR/Cas9技术成功构建Slco1b2基因敲除(KO)大鼠模型。新型大鼠模型显示OATP1B2蛋白表达缺失,没有脱靶效应,也没有对其他转运蛋白的补偿性调节。匹伐他汀的进一步药代动力学研究,OATP1B2的典型底物证实OATP1B2功能缺失。由于胆红素和胆汁酸是OATP1B2的底物,总胆红素的含量,直接胆红素,间接胆红素,Slco1b2KO大鼠血清总胆汁酸明显高于野生型大鼠。这些结果与转子综合征中OATP1B1/3缺失引起的症状一致。因此,这种大鼠模型不仅是研究OATP1B2介导的药物运输的有力工具,也是研究高胆红素血症相关疾病的良好疾病模型。
Organic anion transporting polypeptide 1B1 and 1B3 (OATP1B1/3) as important uptake transporters play a fundamental role in the transportation of exogenous drugs and endogenous substances into cells. Rat OATP1B2, encoded by the Slco1b2 gene, is homologous to human OATP1B1/3. Although OATP1B1/3 is very important, few animal models can be used to study its properties. In this report, we successfully constructed the Slco1b2 knockout (KO) rat model via using the CRISPR/Cas9 technology for the first time. The novel rat model showed the absence of OATP1B2 protein expression, with no off-target effects as well as compensatory regulation of other transporters. Further pharmacokinetic study of pitavastatin, a typical substrate of OATP1B2, confirmed the OATP1B2 function was absent. Since bilirubin and bile acids are the substrates of OATP1B2, the contents of total bilirubin, direct bilirubin, indirect bilirubin, and total bile acids in serum are significantly higher in Slco1b2 KO rats than the data of wild-type rats. These results are consistent with the symptoms caused by the absence of OATP1B1/3 in Rotor syndrome. Therefore, this rat model is not only a powerful tool for the study of OATP1B2-mediated drug transportation, but also a good disease model to study hyperbilirubinemia-related diseases.