Solute carrier organic anion transporter family member 1B3 (OATP1B3) (OATP1B3)

Solute carrier organic anion transporter family member 1B3 (OATP1B3) is a key uptake transporter primarily expressed on the sinusoidal membrane of human hepatocytes (UniProt P54790). It plays a vital role in the hepatic clearance of various endogenous compounds, such as bile acids and bilirubin, as well as a broad range of clinically significant drugs including statins and immunosuppressants. Notably, OATP1B3 is responsible for the hepatic uptake of mycophenolic acid glucuronide (MPAG), the major metabolite of mycophenolate mofetil, which is essential for its enterohepatic recirculation and elimination (Yamaguchi et al., 2008, Drug Metab Dispos). Inhibition of OATP1B3 by drugs like cyclosporine or rifampicin can lead to significant drug-drug interactions, resulting in increased plasma concentrations of substrates and potential toxicity (FDA, 2020, In Vitro Drug Interactions Guidance). Furthermore, OATP1B3 is frequently overexpressed in several cancers, including prostate and colon cancer, where it may influence the uptake of endogenous hormones or chemotherapeutic agents (Nakanishi & Tamai, 2012, J Pharm Sci). Genetic deficiencies in both OATP1B3 and OATP1B1 result in Rotor syndrome, a form of hereditary conjugated hyperbilirubinemia (Van de Steeg et al., 2012, Nat Genet).

Other names

SLCO1B3OATP8LST-2SLC21A8Organic anion-transporting polypeptide 8Liver-specific organic anion transporter 2

Facilitates the uptake of organic anions from the portal blood into hepatocytes via sodium-independent facilitated diffusion across the basolateral (sinusoidal) membrane.