Department of Plastic Surgery, Henan Provincial People's Hospital (Zhengzhou University People's Hospital), Zhengzhou, China.
Exp Dermatol. 2024 Nov;33(11):e70008. doi: 10.1111/exd.70008.
Keloid scarring is a complex fibroproliferative disorder characterised by excessive fibroblast proliferation. Inhibition of cellular glycolysis effectively suppresses the proliferation of keloid fibroblasts (KFs). Neural precursor cell-expressed developmentally downregulated gene 4-like (NEDD4L), a ubiquitin ligase, regulates cell proliferation in different diseases. This study investigated the effects of NEDD4L on glucose metabolism, proliferation and migration in KFs. Primary KFs were isolated from keloid skin tissues obtained from patients with active-stage keloids. Cell transfection was used to upregulate or downregulate NEDD4L and Yin Yang 1 (YY1) in KFs. Protein expression was assessed by immunohistochemistry and western blotting. The viability, proliferative capacity and migration ability of KFs were evaluated using the MTT method and the EdU and wound healing assays, respectively. The regulatory effect of NEDD4L on YY1 ubiquitination was examined by coimmunoprecipitation. The interaction between YY1 and hexokinase 2 (HK2) was confirmed by a dual-luciferase reporter assay. NEDD4L was downregulated, whereas YY1 and HK2 were highly expressed in keloid tissues compared with normal skin. Overexpression of NEDD4L inhibited the proliferation and migration of KFs. NEDD4L promoted YY1 degradation in KFs by inducing its ubiquitination. Upregulation of YY1 induced glucose consumption and lactate production in KFs via the transcriptional regulation of HK2. Increased expression of YY1 reversed the reduced viability, proliferation, and migration of KFs overexpressing NEDD4L. YY1 also reversed the NEDD4L-induced inhibition of glucose consumption and lactate production in KFs. Additionally, an in vivo study confirmed the inhibitory roles of NEDD4L overexpression and YY1 knockdown in keloid formation. NEDD4L suppressed the viability, proliferation and migration of KFs by regulating YY1 ubiquitination-mediated glycolysis through HK2. These findings suggest a novel regulatory axis, NEDD4L/YY1/HK2, that mediates glucose metabolism in keloid formation.
瘢痕疙瘩是一种复杂的纤维增生性疾病，其特征是成纤维细胞过度增殖。抑制细胞糖酵解可有效抑制瘢痕疙瘩成纤维细胞（KFs）的增殖。神经前体细胞表达的发育下调基因 4 样（NEDD4L）是一种泛素连接酶，可调节不同疾病中的细胞增殖。本研究探讨了 NEDD4L 对 KFs 葡萄糖代谢、增殖和迁移的影响。从处于活动期的瘢痕疙瘩患者的瘢痕疙瘩皮肤组织中分离出原代 KFs，通过细胞转染上调或下调 KFs 中的 NEDD4L 和 YY1。通过免疫组织化学和 Western blot 检测蛋白质表达。使用 MTT 法和 EdU 及划痕愈合实验分别评估 KFs 的活力、增殖能力和迁移能力。通过免疫共沉淀检测 NEDD4L 对 YY1 泛素化的调节作用。通过双荧光素酶报告基因实验证实 YY1 与己糖激酶 2（HK2）的相互作用。与正常皮肤相比，瘢痕疙瘩组织中 NEDD4L 下调，而 YY1 和 HK2 高表达。过表达 NEDD4L 可抑制 KFs 的增殖和迁移。NEDD4L 通过诱导其泛素化促进 KFs 中 YY1 的降解。上调 YY1 通过转录调控 HK2 诱导 KFs 中葡萄糖消耗和乳酸生成。过表达 YY1 逆转了过表达 NEDD4L 时 KFs 活力、增殖和迁移的降低。YY1 还逆转了 NEDD4L 诱导的 KFs 中葡萄糖消耗和乳酸生成的抑制作用。此外，体内研究证实了 NEDD4L 过表达和 YY1 敲低在瘢痕疙瘩形成中的抑制作用。NEDD4L 通过调节 YY1 泛素化介导的 HK2 糖酵解来抑制 KFs 的活力、增殖和迁移。这些发现表明，NEDD4L/YY1/HK2 是一种新的调节轴，介导了瘢痕疙瘩形成中的葡萄糖代谢。
