title: Elastin development-associated extracellular matrix constituents of subepithelial connective tissue in human pterygium.
abstract: OBJECTIVE
  We evaluated the expression of several extracellular matrix constituents implicated in the synthesis and reticulation of elastin in human pterygium, according to age and sex of the patients.
  
  
  METHODS
  Pterygia and normal conjunctiva samples were divided into groups according to age (<50/≥50 years) and sex. Tissue was subjected to immunohistochemical staining with anti-lysyl oxidase (LOX), lyxyl oxidase-like 1 (LOXL-1), fibulin (FBLN)-5 and FBLN4, and fibrillin-1 (FBN1) antibodies. Specific primers for the same constituents were used in a quantitative real-time PCR (qRT-PCR) analysis to determine gene expression.
  
  
  RESULTS
  The LOXL-1 (P = 0.0002), FBLN5 (P = 0.0035), and FBN1 (P < 0.0001) mRNAs were significantly higher in pterygium than conjunctiva. No differences were found for LOX and FBLN4 mRNA. The expression of LOXL-1 was not affected by age or sex; however, pterygium from men and patients over 50 years old exhibited significantly higher FBLN5/FBN1 expression than did controls. The LOX gene expression was higher in the pathologic samples from the over 50-year-olds compared to the conjunctiva (P = 0.0396) and in men's versus women's pterygium (P = 0.0173). In general, the levels of LOX, LOXL-1, and FBLN5 decreased with age in healthy samples, while the pathology seemed to have increased expression of the three proteins, and even more so in older patients. The FBLN4 and FBN1 immunostaining was slight in all samples, displaying no differences between groups.
  
  
  CONCLUSIONS
  Several extracellular matrix constituents, LOXs, FBN1, and FBLN5, implicated in the development of elastin, are overexpressed in the subepithelial connective tissue extracellular matrix of human pterygium, supporting our hypothesis that elastic synthesis and reticulation is dysregulated in this type of pathology.
authors.affiliation: Department of Surgery, Medical and Social Sciences, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain Department of Ophthalmology, University Hospital Principe de Asturias, Alcala de Henares, Madrid, Spain.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Pérez-Rico
authors.affiliation: Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Pascual
authors.affiliation: Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Sotomayor
authors.affiliation: Department of Surgery, Medical and Social Sciences, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain.
authors.forename: Ángel
authors.initials: Á
authors.lastname: Asúnsolo
authors.affiliation: Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Cifuentes
authors.affiliation: Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Natalio
authors.initials: N
authors.lastname: García-Honduvilla
authors.affiliation: Department of Medicine and Medical Specialities, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, Spain.
authors.forename: Julia
authors.initials: J
authors.lastname: Buján
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000096:biosynthesis / Q000235:genetics; D003228:Conjunctiva / Q000378:metabolism* / Q000473:pathology; D003238:Connective Tissue / Q000378:metabolism* / Q000473:pathology; D004549:Elastin / Q000096:biosynthesis / Q000235:genetics*; D005109:Extracellular Matrix / Q000378:metabolism* / Q000473:pathology; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011625:Pterygium / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D016326:Extracellular Matrix Proteins; D012333:RNA, Messenger; D004549:Elastin; D000594:Amino Acid Oxidoreductases
keywords: elastin; extracellular matrix; pterygium