Additionally, diabetes markedly increased the immunoreactivity of IL-1β and TNF-α in cells around the glomeruli that are probably tubular cells and/or recruitment and accumulation of interstitial inflammatory cells; sitagliptin treatment decreased the overexpression of IL-1β and TNF-α protein levels in the diabetic kidney (Figures 5(b1) and 5(b2)). Here, TNF is linked to diabetes mellitus.