Figure 6.

The inhibition of SIRT1 by NAM reversed the KGN-mediated antioxidant effect on BM-MSCs. To inhibit the activity of SIRT1, BM-MSCs were treated with 10 mM NAM with or without the supplementation of 10⁻⁶ M KGN. (a) Intracellular ROS of KGN-treated and NAM-treated BM-MSCs were determined using flow cytometry. (b) Quantification data showed that NAM significantly increased the levels of intracellular ROS in BM-MSCs. (c) The protein levels of SIRT1 and AMPK and the phosphorylated levels of AMPK were determined using Western blot assays. (d) The protein levels of intracellular antioxidant enzymes, including SOD1, SOD2, CAT, and GPX1, were determined using Western blot assays. Values are the mean ± SEM of four independent experiments (n = 4) in ROS assays and of three independent experiments (n = 3) in Western blot assays. Statistically significant differences are indicated by ^∗ where p < 0.05 between the indicated groups.