Jiawei Lu, Yifei Feng, Yidan Wang, Yongkai Yu, Wene Zhao, Xuechen Cao, Ziyu Li, Yan Lu
{"title":"Nitric oxide induces apoptosis of human primary melanocytes by regulating calcium homeostasis via VDAC1.","authors":"Jiawei Lu, Yifei Feng, Yidan Wang, Yongkai Yu, Wene Zhao, Xuechen Cao, Ziyu Li, Yan Lu","doi":"10.1007/s11010-025-05361-5","DOIUrl":null,"url":null,"abstract":"<p><p>Vitiligo is an autoimmune skin disease that originates from damage and loss of melanocytes (MCs). Studies have identified abnormal nitric oxide (NO) metabolism in vitiligo patients, but the mechanisms by which NO contributes to MC loss remain unclear. Skin samples from patients with vitiligo and healthy controls were collected to evaluate the expression of three nitric oxide synthases (NOS) isoforms. Keratinocytes, MCs, and fibroblasts were exposed to a cytokine cocktail (IFN-γ, TNF-α, IL-1β and LPS) to simulate the pro-inflammatory microenvironment of vitiligo. Then NOS activation and the capacity for NO production were examined in each cell type. Sodium nitroprusside (SNP) was used as the NO donor to evaluate its cytotoxic effects on MCs. Cell viability, trypan blue staining rate, and lactate dehydrogenase release were measured following SNP exposure. Ultrastructural changes in MCs were observed using transmission electron microscopy. Apoptosis rate, intracellular calcium concentration, and mitochondrial membrane potential were assessed using flow cytometry. BAPTA-AM was used for intracellular calcium chelation and small interfering RNA was used to silence VDAC1 expression in MCs. Inducible NOS (iNOS) expression was significantly upregulated in patients in the active vitiligo lesions. Under pro-inflammatory conditions, keratinocytes and fibroblasts produced increased NO via iNOS activation. MCs exposed to a high-NO environment displayed dose-dependent cellular damage. SNP-treated MCs showed ultrastructural features of apoptosis, including condensed nuclear chromatin and swollen mitochondria. Flow cytometry and analysis of pro-apoptotic markers confirmed mitochondrial-mediated apoptosis in MCs. Both calcium chelation and VDAC1 silencing alleviated the apoptosis of MCs by restoring calcium homeostasis and mitochondrial membrane potential. NO-induced apoptosis in MCs was mediated by calcium overload and mitochondrial dysfunction. iNOS activation may represent a contributor to melanocyte loss in vitiligo and a potential therapeutic target.</p>","PeriodicalId":18724,"journal":{"name":"Molecular and Cellular Biochemistry","volume":" ","pages":""},"PeriodicalIF":3.7000,"publicationDate":"2025-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular and Cellular Biochemistry","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1007/s11010-025-05361-5","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Vitiligo is an autoimmune skin disease that originates from damage and loss of melanocytes (MCs). Studies have identified abnormal nitric oxide (NO) metabolism in vitiligo patients, but the mechanisms by which NO contributes to MC loss remain unclear. Skin samples from patients with vitiligo and healthy controls were collected to evaluate the expression of three nitric oxide synthases (NOS) isoforms. Keratinocytes, MCs, and fibroblasts were exposed to a cytokine cocktail (IFN-γ, TNF-α, IL-1β and LPS) to simulate the pro-inflammatory microenvironment of vitiligo. Then NOS activation and the capacity for NO production were examined in each cell type. Sodium nitroprusside (SNP) was used as the NO donor to evaluate its cytotoxic effects on MCs. Cell viability, trypan blue staining rate, and lactate dehydrogenase release were measured following SNP exposure. Ultrastructural changes in MCs were observed using transmission electron microscopy. Apoptosis rate, intracellular calcium concentration, and mitochondrial membrane potential were assessed using flow cytometry. BAPTA-AM was used for intracellular calcium chelation and small interfering RNA was used to silence VDAC1 expression in MCs. Inducible NOS (iNOS) expression was significantly upregulated in patients in the active vitiligo lesions. Under pro-inflammatory conditions, keratinocytes and fibroblasts produced increased NO via iNOS activation. MCs exposed to a high-NO environment displayed dose-dependent cellular damage. SNP-treated MCs showed ultrastructural features of apoptosis, including condensed nuclear chromatin and swollen mitochondria. Flow cytometry and analysis of pro-apoptotic markers confirmed mitochondrial-mediated apoptosis in MCs. Both calcium chelation and VDAC1 silencing alleviated the apoptosis of MCs by restoring calcium homeostasis and mitochondrial membrane potential. NO-induced apoptosis in MCs was mediated by calcium overload and mitochondrial dysfunction. iNOS activation may represent a contributor to melanocyte loss in vitiligo and a potential therapeutic target.
期刊介绍:
Molecular and Cellular Biochemistry: An International Journal for Chemical Biology in Health and Disease publishes original research papers and short communications in all areas of the biochemical sciences, emphasizing novel findings relevant to the biochemical basis of cellular function and disease processes, as well as the mechanics of action of hormones and chemical agents. Coverage includes membrane transport, receptor mechanism, immune response, secretory processes, and cytoskeletal function, as well as biochemical structure-function relationships in the cell.
In addition to the reports of original research, the journal publishes state of the art reviews. Specific subjects covered by Molecular and Cellular Biochemistry include cellular metabolism, cellular pathophysiology, enzymology, ion transport, lipid biochemistry, membrane biochemistry, molecular biology, nuclear structure and function, and protein chemistry.