Metformin Prevents Renal Stone Formation through an Antioxidant Mechanism In Vitro and In Vivo

Figure 2

Effect of various concentrations of oxalate and metformin on cytotoxicity in cultured HK-2 cells. (a) HK-2 cells were treated with the indicated concentrations (0.05–6.4 mM) of sodium oxalate for 2 days. (b) HK-2 cells were treated with the indicated concentrations (0.5–64 mM) of metformin for 2 days. (c) HK-2 cells were pretreated with different concentrations of metformin (0, 0.5, and 1 mM) for 2 h and then incubated with or without 1.6 mM sodium oxalate for an additional 24 h. Viability of cells was assessed by MTT assay. Percentage of cell viability was relative to the untreated control cells. Values represent mean ± SD of 3 independent experiments. ; , versus control.

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