Effect of Late Second to Early Third Trimester of Pregnancy on the Activity of Renal Organic Anion Transporters (OAT1 and OAT3): A Biomarker Study

Key Points

• This research aims to examine how the activity of renal organic anion transporters OAT1 and OAT3 changes during the late second to early third trimester of pregnancy.
• Measured ratios of biomarkers during late second and early third trimester (T2-T3) compared to postpartum (PP).
• Analyzed net renal secretory clearance and unbound secretory clearance of specific biomarkers including pyridoxic acid and p-cresol sulfate.
• Evaluated changes in OAT1/3 activity based on endogenous biomarker data.
• OAT1/3 activity increased in T2-T3 with ratios of biomarkers ranging from 1.3 to 1.6, except for GCDCA-S and kynurenine where ratios were approximately 5.
• Net renal secretory clearance ratios for multiple biomarkers were consistent with the increased activity, supporting in vivo data for OAT1/3 substrates.