In ob/ob mice, the mRNA and protein expression levels of hepatic Oatp1a1 as well as renal Oatp1a1mRNA expression levels were also down-regulated, and the expression of breast cancer resistance protein (Bcrp) and Oat2 in kidney of rats with T2DM were upregulated [14]. Here, ABCG2 is linked to type 2 diabetes mellitus.