Figure 2. The characteristics of renal cellular aging and injuryinduced by D-galactose in vitro. (A) The morphological changes in the NRK-52E cells with or without 100 mM D-gal treatment for 24 hours by light microscope. (B) The cell viability in the NRK-52E cells exposed to D-gal at 0, 25, 50, 100, and 200 mM for 24 hours. (C) SA-β-gal staining in the NRK-52E cells exposed to D-gal at 0, 50, 100, and 200 mM for 24 hours, and the percentage of SA-β-gal-positive cells. (D) The NRK-52E cells were treated with D-gal at 0, 25, 50, 100, and 200 mM for 24 hours, and subjected to a WB analysis of klotho, p53, p21, IL-1, TGF-β and MCP-1. The data are expressed as the mean ± SD, (n=3), *P < 0.05, **P < 0.01. Abbreviation: D-gal, D-galactose; SA-β-gal, senescence-associated-β-galactosidase; WB, Western blot; IL-1, interleukin-1; TGF-β, transforming growth factor-β; MCP-1, monocyte chemoattractant protein-1.