Table 1.
Role of elastin turnover in ocular diseases. Abbreviations: MMP, Matrix Metalloproteinase; LOX, Lysyl oxidase; BrM EL, Bruch’s membrane elastin layer; CNV, choroidal neovascularization; TIMP, tissue inhibitors of metalloproteinases; EDP, elastin derived peptides; HTRA1, High-Temperature Requirement A Serine Peptidase 1; LoxL1, Lysyl oxidase like 1; POAG, primary open angle glaucoma. The arrows indicate the direction of change.
| Disease | Pathological implications | References |
|---|---|---|
| Floppy eyelid syndrome | ↓ tarsal elastin level, ↑ elastin degradation, ↑ MMP 7 and 9 levels | (Netland et al., 1994; Schlötzer-Schrehardt et al., 2005) |
| Keratoconus | ↓ LOX distribution/activity in the cornea, ↓ elastic fiber system in the cornea | (Bykhovskaya et al., 2012; Dudakova and Jirsova, 2013; Dudakova et al., 2012; White et al., 2017b) |
| Ocular components of Marfan syndrome | ↑ectopia lentis, ↑glaucoma, ↓ retinal/choroidal vascular health | (Di Marino et al., 2020; Nahum and Spierer, 2008; Zadeh et al., 2011) |
| Ocular components of Pseudoxanthoma elasticum | ↑ Calcification and fragmentation of BrM EL, ↑ risk of CNV and macular atrophy | (Charbel Issa et al., 2009; Risseeuw et al., 2020b) |
| Sorsby’s fundus dystrophy | ↑ Subretinal deposits of mutated TIMP-3, ↑ BrM thickening and fragmentation of BrM EL, ↑CNV | (Anand-Apte et al., 2019; Chong et al., 2000) |
| Rhegmatogenous retinal detachment | ↓ LOX activity and ↑ MMP 2 and 9 levels in the vitreous | (Coral et al., 2008) |
| Diabetic retinopathy | ↑Neutrophil elastase levels and ↑vascular permeability, ↓ LOX activity and ↑ MMP 2 and 9 in the vitreous, ↑ serum levels of anti-elastin IgA antibodies | (Coral et al., 2008; Liu et al., 2019; Nicoloff et al., 2000) |
| AMD | ↓ integrity of macular BrM EL, ↑ thinning of macular BrM EL, ↑ serum levels of EDPs, ↑ serum levels of elastin antibodies, ↑Elastin and HTRA1 gene polymorphisms in polypoidal choroidal vasculopathy (PCV) and AMD | (Chong et al., 2005; Dewan et al., 2006; He et al., 2021; Kondo et al., 2008; Morohoshi et al., 2012; Sivaprasad et al., 2005; Tong et al., 2010; Yamashiro et al., 2011; Yanagisawa et al., 2015) |
| Glaucoma (POAG) | ↓LoxL1 and ↑elastin fragmentation/aggregate depositions at the lamina cribrosa, ↑Thickening of the elastic fiber sheath in trabecular meshwork, ↑elastin deposition in the Schlemm’s canal endothelial cells | (Pena et al., 1998; Quigley et al., 1994; Schlötzer-Schrehardt et al., 2012; Tektas and Lütjen-Drecoll, 2009; Umihira, 1993; Umihira et al., 1994) |