LCN2 and type 2 diabetes mellitus: Previous investigations have demonstrated that NGAL is highly expressed in the kidney proximal tubules of diabetic rats [13, 26] and uNGAL is markedly elevated in microalbuminuric patients with T1DM [22, 34] or T2DM [35, 36], uNGAL is positively correlated with proteinuria, and can reflect the severity of diabetic nephropathy [36, 37].