Ligustroflavone alleviates chronic kidney disease by inhibiting ferroptosis through the GSK3β/NRF2 signaling pathway

Chronic kidney disease (CKD) is a global public health concern, characterized by a gradual decline in kidney function, with death of renal tubular epithelial cells (RTECs) as a key pathological mechanism. This study investigated the protective effect of ligustroflavone in CKD and its potential molecular mechanisms.
In vivo, the unilateral ureteral obstruction (UUO) and folic acid-induced nephropathy (FAN) mouse models were employed to assess the effects of ligustroflavone. In vitro, RTECs were treated with erastin. Western blotting, qRT-PCR, immunofluorescence (IF), and immunohistochemistry (IHC) were performed to detect renal tubular injury both in vivo and in vitro.
In vivo, ligustroflavone treatment significantly improved renal tubular damage and interstitial fibrosis in mice. Furthermore, our results demonstrated that ligustroflavone alleviated ferroptosis of RTECs by inhibiting GSK3β activity and reducing lipid peroxidation in mice. In vitro, ligustroflavone treatment inhibited erastin-induced ferroptosis in RTECs. In addition, ligustroflavone inhibited activation of myofibroblasts induced by ferroptosis of RTECs. Mechanistically, ligustroflavone exerted it’s protect effects through the GSK3β/NRF2 pathway by inhibiting GSK3β and activating NRF2, thereby promoting GPX4 expression and suppressing ferroptosis.
In summary, ligustroflavone inhibits ferroptosis in RTECs and confers protection in CKD. These findings suggest that ligustroflavone holds promise as a potential therapeutic agent for CKD.

慢性肾脏病（Chronic kidney disease, CKD）是全球性公共卫生难题，以肾功能进行性减退为特征，其核心病理机制为肾小管上皮细胞（renal tubular epithelial cells, RTECs）死亡。本研究探讨了女贞黄酮（ligustroflavone）对CKD的保护作用及其潜在分子机制。
体内实验采用单侧输尿管梗阻（unilateral ureteral obstruction, UUO）与叶酸诱导性肾病（folic acid-induced nephropathy, FAN）小鼠模型，以评估女贞黄酮的干预效果；体外实验则使用艾拉斯汀（erastin）处理RTECs。通过蛋白质免疫印迹（Western blotting）、定量实时聚合酶链反应（qRT-PCR）、免疫荧光（IF）及免疫组织化学（IHC）技术，检测体内外模型的肾小管损伤程度。
体内实验结果显示，女贞黄酮给药可显著改善小鼠肾小管损伤及间质纤维化。进一步研究表明，女贞黄酮可通过抑制糖原合成激酶3β（GSK3β）活性、减少体内脂质过氧化，从而缓解小鼠RTECs的铁死亡（ferroptosis）。体外实验中，女贞黄酮可抑制艾拉斯汀诱导的RTECs铁死亡；此外，其还可阻断RTECs铁死亡所诱导的肌成纤维细胞（myofibroblasts）活化。机制层面，女贞黄酮通过抑制GSK3β、激活核因子E2相关因子2（NRF2），经GSK3β/NRF2通路发挥保护作用，进而促进谷胱甘肽过氧化物酶4（GPX4）的表达并抑制铁死亡。
综上，女贞黄酮可抑制RTECs的铁死亡，对CKD产生保护作用。本研究结果提示，女贞黄酮有望成为CKD潜在的治疗候选药物。