Solute carrier family 22 member 8 (OAT3) (SLC22A8)

Solute carrier family 22 member 8 (SLC22A8), commonly known as Organic Anion Transporter 3 (OAT3), is a multispecific transmembrane protein primarily localized to the basolateral membrane of renal proximal tubule cells [1, 4]. It plays a fundamental role in renal physiology by mediating the uptake of a diverse array of endogenous organic anions, such as urate and prostaglandins, as well as exogenous compounds, including many clinically significant drugs like antibiotics, diuretics, and statins [1, 5, 13]. By functioning as an organic anion/dicarboxylate exchanger, SLC22A8 facilitates the first step of renal tubular secretion, thereby governing the systemic clearance and half-life of its substrates [4, 11, 12]. Beyond the kidney, it is expressed in the blood-brain barrier and choroid plexus, where it contributes to the detoxification of the central nervous system by removing metabolites from the cerebrospinal fluid [4, 9, 17]. Due to its broad substrate specificity, SLC22A8 is a major site for clinically relevant drug-drug interactions, where competition for the transporter can lead to altered drug exposure and potential toxicity [3, 11, 14]. Dysregulation of SLC22A8 is implicated in metabolic disorders like gout and hyperuricemia, and its expression levels have been identified as prognostic markers in clear cell renal cell carcinoma [2, 6, 15].

Other names

OAT3hOAT3Organic anion transporter 3Organic anion/dicarboxylate exchangerSolute carrier family 22 (organic anion transporter) member 8

Drugs targeting SLC22A8 primarily act as competitive inhibitors (e.g., probenecid, benzbromarone, cilastatin) to reduce the renal clearance of co-administered drugs or to prevent the uptake of nephrotoxic substances [10, 11, 14]. Additionally, many drugs act as substrates (e.g., ciprofloxacin, methotrexate, furosemide), utilizing the transporter for their systemic elimination [3, 5, 7].