SLC22A5 and diabetes mellitus: Interestingly, as shown in Figure 2C, protein levels of PPAR-α increased in STZ-induced diabetic rats compared to control rats, indicating that PPAR-α expression is not correlated with either γ-BBH or OCTN2 expression in STZ-induced diabetes but is more closely associated with increased plasma NEFAs, its natural ligand (Table 1).