NFE2L2 and type 2 diabetes mellitus: However, the feasibility of a plasma assay of Nrf2 has been demonstrated by Ban WH et al. [52], who reported that plasma Nrf2 concentrations gradually increased with disease severity and the extent of systemic inflammation in patients with COPD, and by Sireesh D. et al. [53], who found that plasma Nrf2 concentrations were lower in patients with type 2 diabetes when compared to control subjects.