TNF and Nephropathy: In light of our findings of TAA-induced kidney damage that was protected by metformin, we assessed the kidney tissue levels of phospho-AMPK (Figure 2A,B), total AMPK (Figure 2A,C), MDA (Figure 2D), SOD (Figure 2E), and TNF-α (Figure 2F) as well as blood levels of MDA, hsCRP, and TNF-α (data not shown) in all rats at the end of the experiment.