Obesity-related drug transporter expression alterations in human liver and kidneys.

Background: Pathophysiological changes associated with obesity might impact various drug pharmacokinetics (PK) parameters. The liver and kidneys are the primary organs involved in drug clearance, and the function of hepatic and renal transporters is critical to efficient drug elimination (or reabsorption). Considering the impact of an increased BMI on the drug's PK is crucial in directing dosing decisions. Given the critical role of transporters in drug biodisposition, this study investigated how overweight and obesity affect the gene expression of renal and hepatic drug transporters.

Methods: Human liver and kidney samples were collected post-mortem from 32 to 28 individuals, respectively, which were divided into the control group (lean subjects; 18.5 ≤ BMI < 25 kg/m²) and the study group (overweight/obese subjects; BMI ≥ 25 kg/m²). Real-time quantitative PCR was performed for the analysis of 84 drug transporters.

Results: Our results show significant changes in the expression of genes involved in human transporters, both renal and hepatic. In liver tissue, we found that ABCC4 was up-regulated in overweight/obese subjects. In kidney tissue, up-regulation was only observed for ABCC10, while the other differentially expressed genes were down-regulated: ABCA1, ABCC3, and SLC15A1.

Conclusions: The observed alterations may be reflected by the differences in drug PK between lean and obese populations. However, these findings need further evaluation through the proteomic and functional study of these transporters in this patient population.