Ligustrazine attenuates ferroptosis in proximal straight tubule cells via IGF2BP1–Odc1 regulation in a CKD model

BACKGROUND: Chronic kidney disease (CKD) is a long-term progressive condition characterized by a decline in renal function, for which effective treatment strategies remain limited. This study aimed to evaluate the effectiveness of ligustrazine for CKD and elucidate its underlying molecular mechanisms. METHODS: A CKD rat model was established using a 2.5% adenine suspension for two consecutive weeks via intragastric administration, followed by a two-week intervention with ligustrazine from day 15. In vitro, primary proximal straight tubule cells (PSTCs) were treated with adenine for 48 h to simulate chronic kidney injury. Biotin-labeled ligustrazine was subjected to LC-MS/MS analysis to identify the target proteins. Single-cell sequencing was performed on rats in the control, CKD, and ligustrazine groups to identify the key genes and characteristic cell subpopulations involved in CKD treatment. Additionally, overexpression and knockdown plasmids of Ornithine Decarboxylase 1 (Odc1) and methyltransferase like 3 (Mettl3) were constructed to investigate their roles in alleviating CKD through cellular and animal experiments. RESULTS: Ligustrazine intervention significantly alleviated kidney damage in CKD rats. Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was identified as an intracellular target of ligustrazine. Odc1 was confirmed as a potential key gene, and PST cells were identified as a characteristic cell subset in the treatment of CKD with ligustrazine. Compared to adenine treatment, ligustrazine intervention inhibited the mRNA and protein expression of Odc1, while promoting the mRNA and protein expression of Glutathione Peroxidase 4 (Gpx4), without affecting the expression of IGF2BP1. Additionally, ligustrazine intervention reduced PSTCs apoptosis and lowered the expression of 4-HNE. Notably, Odc1 promoted adenine-induced PSTCs ferroptosis, whereas ligustrazine intervention weakened the binding of IGF2BP1 to m6A-modified Odc1 mRNA, shortening the half-life of Odc1 mRNA, thus inhibiting ferroptosis. CONCLUSIONS: Ligustrazine reduced the binding of IGF2BP1 to Odc1 mRNA, downregulated Odc1 protein expression, thereby decreasing ferroptosis, and restoring renal function.