Renal efflux transporter expression in pregnant mice with Type I diabetes

Prior research suggests that sex hormones and metabolic changes, such as obesity and hyperglycemia, can alter renal transporter expression in rodents. The purpose of this study was to characterize the expression of kidney efflux transporters and regulatory transcription factors in response to Type I diabetes and pregnancy. Female C57BL/6 mice were treated with multiple low doses of streptozotocin (STZ) to induce hyperglycemia and then mated with normoglycemic male mice. Transporter mRNA and protein expression were quantified in kidneys from vehicle- and STZ-treated non-pregnant and pregnant mice on gestation day 14. Pregnancy decreased the expression of Mdr1b, Mrp4, and 5 proteins and increased the mRNA and protein expression of Mrp3 by 50–60%. STZ treatment elevated Mrp1, 2, 4, and 5 and reduced Mrp3, 6, and Mdr1b mRNA and/or protein in non-pregnant mice. Pregnancy had little effect on STZ-mediated changes in renal efflux transporter expression. Transcriptional profiles of Hnf1α, PXR, AhR, and Nrf2 were altered in patterns similar to some efflux transporters suggesting potential involvement in their regulation. Taken together, these results suggest that renal drug efflux transporters and regulatory signaling pathways are altered by endocrine and metabolic changes that occur during pregnancy and Type I diabetes.

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► Renal transporters are differentially regulated by diabetes and pregnancy in mice.
► Pregnancy has minimal effect on diabetes-induced transporter changes.
► Expression of Mrp3 was increased in pregnancy and reduced by diabetes.
► Mrp1, 4, and 5 were increased by diabetes similar to Nrf2 and its target genes.