Zhang Shan, Wen Zhige, Chen Yupeng, Yang Yanan, Song Changheng, Wang Jialing, Zhou Yang, Ni Qing
Department of Endocrinology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China.
Phytomedicine. 2025 May 19;145:156776. doi: 10.1016/j.phymed.2025.156776.
BACKGROUND: Diabetic nephropathy (DN) is often accompanied by dysregulated lipid metabolism, which exacerbates renal injury. Keluoxin (KLX), a therapeutic agent approved by the National Medical Products Administration of China, has demonstrated efficacy in treating DN. However, the mechanisms underlying KLX's beneficial effects, particularly its role in lipid metabolism regulation, remain poorly understood. PURPOSE: To investigate the molecular mechanisms by which KLX ameliorates ectopic lipid deposition (ELD) in DN. METHODS: Spontaneous diabetic nephropathy was induced in KKAy mice, which were then administered oral KLX at doses of 0.9 g/kg or 1.8 g/kg for 12 weeks. The effects of KLX on blood glucose, lipid profiles, proteinuria, and renal function were evaluated. Pathological changes, with a particular focus on ELD, were assessed using Masson's trichrome staining, PASM staining, electron microscopy, and Oil Red O staining. The regulation of the AMPK/NFκB signaling axis was examined through RT-qPCR and Western blotting. In vitro, high-glucose/high-fat conditions were employed to simulate a diabetic environment. The effects of KLX on mesangial cell proliferation and fibrosis under glucolipotoxic conditions were assessed using ROS staining, EDU staining, and SMA staining. To confirm the role of AMPK in KLX-mediated renal protection, the AMPK inhibitor compound C were used for further validation. RESULTS: KLX treatment significantly reduced blood glucose levels (p<0.01), urinary protein excretion (p<0.05; p<0.01), and serum creatinine and blood urea nitrogen levels (p<0.01), improving renal function in DN mice. Histological analysis revealed that KLX alleviated mesangial expansion, matrix thickening, and renal fibrosis, thus preserving renal structure. It also led to a reduction in peripheral blood triglyceride levels (p<0.01) and mitigated lipid accumulation in both the liver and kidneys. KLX downregulated the mRNA expression of genes associated with lipid synthesis (Fasn, Srebp1, Acc) and fibrosis (Fn1, Pai1), while upregulating the expression of genes involved in lipid breakdown (Cpt1, Cpt2) and antioxidant defense (Sod2, Sod3, Cat). This treatment also enhanced the expression of AMPK and phosphorylated(p) AMPK, while inhibiting NFκB and pNF-κBp65. In vitro, compound C partially inhibited the effects of KLX, and subsequent experiments confirmed that KLX exerts its lipid-regulatory effects through the AMPK/NF-κB axis, thereby attenuating mesangial cell proliferation, fibrosis, and oxidative stress. CONCLUSION: These findings provide compelling evidence that KLX regulates lipid metabolism via the AMPK/NFκB axis, inhibiting lipid synthesis and promoting fatty acid oxidation. By reducing ELD, KLX protects renal structure and function in DN, offering a promising therapeutic approach for this condition.
背景:糖尿病肾病(DN)常伴有脂质代谢失调,这会加剧肾损伤。克络新(KLX)是中国国家药品监督管理局批准的一种治疗药物,已证明在治疗DN方面有效。然而,KLX有益作用的潜在机制,尤其是其在脂质代谢调节中的作用,仍知之甚少。 目的:研究KLX改善DN中异位脂质沉积(ELD)的分子机制。 方法:在KKAy小鼠中诱导自发性糖尿病肾病,然后以0.9 g/kg或1.8 g/kg的剂量口服KLX,持续12周。评估KLX对血糖、血脂、蛋白尿和肾功能的影响。使用Masson三色染色、PASM染色、电子显微镜和油红O染色评估病理变化,特别关注ELD。通过RT-qPCR和蛋白质印迹法检测AMPK/NFκB信号轴的调节。在体外,采用高糖/高脂条件模拟糖尿病环境。使用ROS染色、EDU染色和SMA染色评估KLX在糖脂毒性条件下对系膜细胞增殖和纤维化的影响。为了证实AMPK在KLX介导的肾脏保护中的作用,使用AMPK抑制剂化合物C进行进一步验证。 结果:KLX治疗显著降低了血糖水平(p<0.01)、尿蛋白排泄(p<0.05;p<0.01)以及血清肌酐和血尿素氮水平(p<0.01),改善了DN小鼠的肾功能。组织学分析显示,KLX减轻了系膜扩张、基质增厚和肾纤维化,从而保护了肾脏结构。它还导致外周血甘油三酯水平降低(p<0.01),并减轻了肝脏和肾脏中的脂质积累。KLX下调了与脂质合成(Fasn、Srebp1、Acc)和纤维化(Fn1、Pai1)相关基因的mRNA表达,同时上调了参与脂质分解(Cpt1、Cpt2)和抗氧化防御(Sod2、Sod3、Cat)的基因表达。这种治疗还增强了AMPK和磷酸化(p)AMPK的表达,同时抑制了NFκB和pNF-κBp65。在体外,化合物C部分抑制了KLX的作用,随后的实验证实KLX通过AMPK/NF-κB轴发挥其脂质调节作用,从而减轻系膜细胞增殖、纤维化和氧化应激。 结论:这些发现提供了令人信服的证据,表明KLX通过AMPK/NFκB轴调节脂质代谢,抑制脂质合成并促进脂肪酸氧化。通过减少ELD,KLX保护DN中的肾脏结构和功能,为这种疾病提供了一种有前景的治疗方法。
J Diabetes Res. 2025-7-17
Front Endocrinol (Lausanne). 2025-6-6