##SRS 16-86 downregulated the expression of ROS and 4-hydroxynonenal level in DN
Ferroptosis is caused by the lipid peroxidation induced by ROS accumulation: ROS decomposition produces malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), which then form covalent adjuncts with proteins, DNA, lipids, and other macromolecules to cross-link and inactivate proteins that promote ferroptosis, thus precipitating cell membrane rupture and ferroptosis. In this study, we detected the ROS (Figure 3B) and 4HNE (Figure 4A,4D) expressions. 4HNE and ROS levels were significantly upregulated post-DN in the DN group compared to the control group. After treatment with SRS 16-86, 4HNE and ROS expression was upregulated, demonstrating that SRS 16-86 could inhibit lipid peroxidation.
##SRS 16-86 upregulated thelevel of xCT, GSH, and GPX4 in DN
The xCT-GSH-GPX4 axis contributed to the negative regulation of ferroptoptic-related cell death. High extracellular glutamate levels can inhibit systemic xCT activity and thus induce ferroptosis. We detected the expression of xCT, GPX4, and GSH post-DN (Figure 4A,4B,4C,4E). xCT, GPX4, and GSH levels were significantly reduced post-DN in the DN group compared to the control group. These results indicated that the capacity of peroxidation repair in the kidneys of diabetic rats was dramatically reduced. We also found that the expression of xCT, GPX4, and GSH were upregulated after treatment with SRS 16-86. The antioxidant capacity was repaired in the SRS group.