■瘢痕疙瘩是由异常的成纤维细胞增殖和过度的细胞外基质(ECM)产生引起的慢性增生性纤维化疾病。许多纤维化疾病受到铁凋亡的显著影响,靶向铁凋亡可以有效缓解纤维化发展。本研究旨在探讨铁性凋亡在瘢痕疙瘩发生发展中的作用及机制。
■收集来自瘢痕疙瘩患者的瘢痕疙瘩组织和来自健康对照的正常皮肤组织。铁含量,脂质过氧化(LPO)水平,和铁凋亡相关基因的mRNA和蛋白表达,包括溶质载体家族7成员11(SLC7A11),谷胱甘肽过氧化物酶4(GPX4),转铁蛋白受体(TFRC),并测定核因子红系2相关因子2(Nrf2)。使用透射电子显微镜(TEM)观察线粒体形态。瘢痕疙瘩成纤维细胞(KFs)从瘢痕疙瘩组织中分离,并用铁凋亡抑制剂铁抑素-1(fer-1)或铁凋亡激活剂erastin治疗。铁含量,铁凋亡相关标志物水平,LPO液位,线粒体膜电位,ATP含量,并检测到KFs中的线粒体形态。此外,α-平滑肌肌动蛋白(α-SMA)的蛋白质水平,胶原蛋白I,和胶原蛋白III进行了测量,以研究铁死亡是否影响KF的纤维化。
■我们发现瘢痕疙瘩组织和KFs中铁含量和LPO水平显著升高。SLC7A11,GPX4和Nrf2在瘢痕疙瘩组织和KFs中下调,TFRC上调。瘢痕疙瘩组织和KFs中的线粒体表现为铁凋亡相关病理。Fer-1处理降低了铁含量,抑制KFs的铁凋亡和线粒体功能障碍,此外,铁抑制素-1抑制α-SMA蛋白表达,胶原蛋白I,和KF中的胶原蛋白III。而擦除素处理显示出相反的结果。
■瘢痕疙瘩中存在铁凋亡。Ferrostatin-1通过抑制铁蛋白凋亡抑制瘢痕疙瘩ECM沉积和纤维化,erastin通过强化铁蛋白诱导ECM沉积和纤维化。
UNASSIGNED: Keloid is a chronic proliferative fibrotic disease caused by abnormal fibroblasts proliferation and excessive extracellular matrix (ECM) production. Numerous fibrotic disorders are significantly influenced by ferroptosis, and targeting ferroptosis can effectively mitigate fibrosis development. This study aimed to investigate the role and mechanism of ferroptosis in keloid development.
UNASSIGNED: Keloid tissues from keloid patients and normal skin tissues from healthy controls were collected. Iron content, lipid peroxidation (LPO) level, and the mRNA and protein expression of ferroptosis-related genes including solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), transferrin receptor (TFRC), and nuclear factor erythroid 2-related factor 2 (Nrf2) were determined. Mitochondrial morphology was observed using transmission electron microscopy (TEM). Keloid fibroblasts (KFs) were isolated from keloid tissues, and treated with ferroptosis inhibitor ferrostatin-1 (fer-1) or ferroptosis activator erastin. Iron content, ferroptosis-related marker levels, LPO level, mitochondrial membrane potential, ATP content, and mitochondrial morphology in KFs were detected. Furthermore, the protein levels of α-smooth muscle actin (α-SMA), collagen I, and collagen III were measured to investigate whether ferroptosis affect fibrosis in KFs.
UNASSIGNED: We found that iron content and LPO level were substantially elevated in keloid tissues and KFs. SLC7A11, GPX4, and Nrf2 were downregulated and TFRC was upregulated in keloid tissues and KFs. Mitochondria in keloid tissues and KFs exhibited ferroptosis-related pathology. Fer-1 treatment reduced iron content, restrained ferroptosis and mitochondrial dysfunction in KFs, Moreover, ferrostatin-1 restrained the protein expression of α-SMA, collagen I, and collagen III in KFs. Whereas erastin treatment showed the opposite results.
UNASSIGNED: Ferroptosis exists in keloid. Ferrostatin-1 restrained ECM deposition and fibrosis in keloid through inhibiting ferroptosis, and erastin induced ECM deposition and fibrosis through intensifying ferroptosis.