Department of Pharmaceutics, Rutgers, the State University of New Jersey, 160 Frelinghuysen Road, Piscataway, New Jersey, 08854, USA.
AAPS J. 2021 Mar 11;23(2):41. doi: 10.1208/s12248-021-00575-z.
Organic anion transporter 3 (OAT3) plays an important role in the disposition of various anionic drugs which impacts the pharmacokinetics and pharmacodynamics of the therapeutics, thus influencing the pharmacological effects and toxicity of the drugs. In this study, we investigated the effect of insulin on the regulation of OAT3 function, expression, and SUMOylation. We demonstrated that insulin induced an increase in OAT3 transport activity through a dose- and time-dependent manner in COS-7 cells. The insulin-induced elevation in OAT3 function was blocked by PKA inhibitor H89, which correlated well with OAT3 protein expression. Moreover, both PKA activator Bt2-cAMP-induced increase and insulin-induced increase in OAT3 function were blocked by PKB inhibitor AKTi1/2. To further investigate the involvement of SUMOylation, we treated OAT3-expressing cells with insulin in presence or absence of H89 or AKTi1/2 followed by examining OAT3 SUMOylation. We showed that insulin enhanced OAT3 SUMOylation, and such enhancement was abrogated by H89 and AKTi1/2. Lastly, insulin increased OAT3 function and SUMOylation in rat kidney slice. In conclusion, our investigations demonstrated that insulin regulated OAT3 function, expression, and SUMOylation through PKA/PKB signaling pathway. Graphical abstract.
有机阴离子转运蛋白 3（OAT3）在各种阴离子药物的处置中发挥着重要作用，这影响了治疗药物的药代动力学和药效学，从而影响了药物的药理作用和毒性。在这项研究中，我们研究了胰岛素对 OAT3 功能、表达和 SUMO 化的调节作用。我们证明，胰岛素在 COS-7 细胞中以剂量和时间依赖的方式诱导 OAT3 转运活性增加。PKA 抑制剂 H89 阻断了胰岛素诱导的 OAT3 功能升高，这与 OAT3 蛋白表达很好地相关。此外，PKA 激活剂 Bt2-cAMP 诱导的 OAT3 功能增加和胰岛素诱导的 OAT3 功能增加均被 PKB 抑制剂 AKTi1/2 阻断。为了进一步研究 SUMO 化的参与，我们用胰岛素处理表达 OAT3 的细胞，然后在存在或不存在 H89 或 AKTi1/2 的情况下检查 OAT3 SUMO 化。我们表明胰岛素增强了 OAT3 SUMO 化，这种增强被 H89 和 AKTi1/2 阻断。最后，胰岛素增加了大鼠肾切片中的 OAT3 功能和 SUMO 化。总之，我们的研究表明，胰岛素通过 PKA/PKB 信号通路调节 OAT3 的功能、表达和 SUMO 化。
