EP300-mediated crotonylation of malic enzyme 1 promotes ferroptosis in renal tubular epithelial cells
10.12025/j.issn.1008-6358.2026.20260387
- VernacularTitle:EP300介导苹果酸酶1巴豆酰化修饰促进肾小管上皮细胞铁死亡
- Author:
Yingxiang LI
1
;
Siyu BAO
1
;
Zixuan XUN
1
;
Daxi WANG
1
;
Shuan ZHAO
1
;
Yi FANG
2
Author Information
1. Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
2. Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai 200032, China;Shanghai Clinical Research Center for Kidney Diseases, Shanghai 200032, China;Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai 200032, China.
- Publication Type:Originalarticle
- Keywords:
acute kidney injury;
malic enzyme 1;
crotonylation modification;
ferroptosis;
renal fibrosis
- From:
Chinese Journal of Clinical Medicine
2026;33(5):762-771
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the role of E1A binding protein p300 (EP300)-mediated crotonylation (Kcr) modification of malic enzyme 1 (ME1) in ferroptosis of renal tubular epithelial cells. Methods C57BL/6 mice were divided into Sham operation group (Sham group), DMSO vehicle control + ischemia-reperfusion (IR) injury group (Vehi + IR group), and EP300 inhibitor C646 + IR injury group (C646 + IR group), with 12 mice in each group. Pathological changes in renal tissues were evaluated in each group, and indicators of renal function, ferroptosis, and fibrosis were assessed. Another 24 mice were used to establish the IR injury model to analyze changes in Kcr modification levels and EP300 expression over the 14-day course of IR injury. The in vitro HK-2 cell experimental model was established and divided into control group, hypoxia/reoxygenation (H/R) group, and C646 + H/R group. Corresponding HK-2 cells were transfected with the ME1-K337R plasmid, in which lysine 337 (K) was mutated to arginine (R) to mimic the de-Kcr modification. Small interfering RNA was used to target EP300 and transfect the cells in order to obtain EP300 knockdown cells (siEP300). The expression of ferroptosis-related proteins and fibrosis phenotypes was detected. Results At 14 d after IR injury, the protein Kcr level and EP300 expression were increased in mice. Compared with the Sham group, the Vehi+IR group showed markedly disrupted renal tissue structure, extensive red collagen deposition in the renal interstitium, decreased expression levels of glutathione, reduced nicotinamide adenine dinucleotide phosphate (NADPH), and glutathione peroxidase 4 (GPX4, P＜0.01), increased malondialdehyde and serum creatinine levels (P＜0.01), decreased ME1 enzymatic activity (P＜0.001), and increased expression of fibronectin 1 and smooth muscle actin-α (P＜0.001). Compared with the Vehi+IR group, the C646+IR group showed alleviated renal pathological injury, improved renal function, and reduced ferroptosis and fibrosis (P＜0.05). Compared with the control group, HK-2 cells subjected to H/R treatment exhibited aggravated ferroptosis and fibrosis (P＜0.05); compared with the H/R group, the C646+H/R group showed reduced ferroptosis and fibrosis (P＜0.05). Transfection with the ME1-K337R plasmid and siEP300 showed reduced ME1 Kcr, ferroptosis, and fibrosis. Conclusions EP300 contributes to ferroptosis in renal tubular epithelial cells by mediating ME1 crotonylation, and inhibition of EP300 may help alleviate the chronic progression following IR injury.
