Subretinal fibrosis is an end stage of neovascular age-related macular degeneration, characterized by fibrous membrane formation after choroidal neovascularization. An initial step of the pathogenesis is an epithelial-mesenchymal transition (EMT) of retinal pigment epithelium cells. αB-crystallin plays multiple roles in age-related macular degeneration, including cytoprotection and angiogenesis. However, the role of αB-crystallin in subretinal EMT and fibrosis is unknown. Herein, we showed attenuation of subretinal fibrosis after regression of laser-induced choroidal neovascularization and a decrease in mesenchymal retinal pigment epithelium cells in αB-crystallin knockout mice compared with wild-type mice. αB-crystallin was prominently expressed in subretinal fibrotic lesions in mice. In vitro, overexpression of αB-crystallin induced EMT, whereas suppression of αB-crystallin induced a mesenchymal-epithelial transition. Transforming growth factor-β2-induced EMT was further enhanced by overexpression of αB-crystallin but was inhibited by suppression of αB-crystallin. Silencing of αB-crystallin inhibited multiple fibrotic processes, including cell proliferation, migration, and fibronectin production. Bone morphogenetic protein 4 up-regulated αB-crystallin, and its EMT induction was inhibited by knockdown of αB-crystallin. Furthermore, inhibition of αB-crystallin enhanced monotetraubiquitination of SMAD4, which can impair its nuclear localization. Overexpression of αB-crystallin enhanced nuclear translocation and accumulation of SMAD4 and SMAD5. Thus, αB-crystallin is an important regulator of EMT, acting as a molecular chaperone for SMAD4 and as its potential therapeutic target for preventing subretinal fibrosis development in neovascular age-related macular degeneration.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4822331 | PMC |
http://dx.doi.org/10.1016/j.ajpath.2015.11.014 | DOI Listing |
Int J Mol Med
March 2025
Department of Ophthalmology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China.
Retinal pigment epithelial (RPE) cells undergoing epithelial‑mesenchymal transition (EMT) are a key factor in promoting the progression of subretinal fibrosis. The klotho protein and gene exert anti‑fibrotic effects in multiple fibrotic diseases. However, the mechanisms involved in the role of klotho are unclear in subretinal fibrosis.
View Article and Find Full Text PDFAging Cell
January 2025
Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
Neovascular age-related macular degeneration (nAMD), characterized by choroidal neovascularization (CNV), is one of the leading causes of severe visual impairment and irreversible vision loss around the world. Subretinal fibrosis (SRF) contributes to the incomplete response to anti-vascular endothelial growth factor (VEGF) treatment and is one of the main reasons for long-term poor visual outcomes in nAMD. Reducing SRF is urgently needed in the anti-VEGF era.
View Article and Find Full Text PDFAdv Mater
December 2024
Department of Thoracic Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
Ribonucleoprotein (RNP)-based CRISPR/Cas9 genome editing holds great potential for the treatment of choroidal neovascularization (CNV), which however, is challenged by the lack of efficient cytosolic protein delivery tools. Herein, reversibly-phosphorylated pro-proteins (P-proteins) with conjugated adenosine triphosphate (ATP) tags are engineered and coupled with a membrane-penetrating, guanidine-enriched, α-helical polypeptide (GP) to mediate robust and universal cytosolic delivery. GP forms salt-stable nanocomplexes (NCs) with P-proteins via electrostatic interaction and salt bridging, and the helix-assisted, strong membrane activities of GP enabled efficient cellular internalization and endolysosomal escape of NCs.
View Article and Find Full Text PDFGraefes Arch Clin Exp Ophthalmol
December 2024
Doheny Eye Institute, University of California, Los Angeles, 150 N. Orange Grove Blvd, Suite 232, Pasadena, CA, USA.
Anti-vascular endothelial growth factor (VEGF) therapies have transformed the treatment of retinal diseases. However, VEGF signaling is only one component of the complex, multifactorial pathophysiology of retinal diseases, and many patients have residual disease activity despite ongoing anti-VEGF treatment. The angiopoietin/tyrosine kinase with immunoglobulin and epidermal growth factor receptor-2 (Ang/Tie2) signaling pathway is critical to endothelial cell homeostasis, survival, integrity, and vascular stability.
View Article and Find Full Text PDFExpert Opin Drug Saf
December 2024
Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Department of Ophthalmology, Chengdu Fifth People's Hospital (The Second Clinical Medical College, Affiliated Fifth People's Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China.
Background: Faricimab is a novel bispecific antibody drug for treating retinal disease. We aim to study the adverse events of faricimab based on the FDA Adverse Event Reporting System (FAERS) database.
Research Design And Methods: The FAERS data from 2020 to 2024 was extracted to conduct disproportionality analysis.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!