Abstract:
The kidney is a vital organ for the elimination of therapeutic drugs and their metabolites. Renal drug transporters, which are primarily located in the renal proximal tubules, play an important role in tubular secretion and reabsorption of drug molecules in the kidney. Tubular secretion is characterized by high clearance capacities, broad substrate specificities, and distinct charge selectivity for organic cations and anions. In the past two decades, substantial progress has been made in understanding the roles of transporters in drug disposition, efficacy, toxicity and drug–drug interactions (DDIs). In the kidney, several transporters are involved in renal handling of organic cation (OC) and organic anion (OA) drugs. These transporters are increasingly recognized as the target for clinically significant DDIs. This review focuses on the functional characteristics of major human renal drug transporters and their involvement in clinically significant DDIs.
Key Words
Renal drug transporters; Drug–drug interactions; Organic cations; Organic anions; Nephrotoxicity
Citation: Jia Yin, Joanne Wang Renal Drug Transporters And Their Significance In Drug–drug Interactions http://dx.doi.org/10.1016/j.apsb.2016.07.013
Received: 27 April 2016, Revised: 30 June 2016, Accepted: 7 July 2016, Available online: 9 August 2016
Copyright: © 2016 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical
Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Conclusions
In conclusion, renal drug transporters play an important role in drug disposition, efficacy and toxicity. Like drug-metabolizing enzymes, they are also the target sites for DDIs. Despite the significant progresses made in our understanding on drug transporters, our knowledge of renal drug transporters and our comprehension of their roles in the kidney and the mechanisms of renal transporter-mediated DDIs are still limited. There are still significant challenges to predict and understand DDIs mediated by renal drug transporters. For example, it is still difficult to precisely locate the actual sites (apical vs. basal membranes) of renal DDIs in vivo. While the plasma concentrations of the inhibitor drug are used for DDI prediction, the actual concentrations of inhibitor that the transporter encounters at the site of inhibition may be significantly different and difficult to measure. Lastly, substrate-dependent and time-dependent inhibitions have been recently reported 136, 137, 138 and 139, which further complicates the assessment and in vitro–to–in vivo prediction of DDIs. Nevertheless, the field of drug transporters is rapidly evolving. With the conceptual and technological advancements in drug transport research, we are now at the forefront to gain a better understanding of renal drug transporters, predict and ameliorate adverse renal DDIs, and design beneficial DDIs to improve drug efficacy and minimize drug toxicity.
Acknowledgements
This study was supported by the U. S. National Institutes of Health National Institute of General Medical Sciences [Grant R01 GM066233] and the National Center for Advancing Translational Sciences [Grant TL1 TR000422]. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.