title: Age related changes in the non-collagenous components of the extracellular matrix of the human lamina cribrosa.
abstract: OBJECTIVE
  To investigate age related alterations in the non-collagenous components of the human lamina cribrosa.
  
  
  METHODS
  Fibronectin, elastin, and glial fibrillary acidic protein (GFAP) staining were assessed in young and old laminae cribrosae. An age range (7 days to 96 years) of human laminae cribrosae were analysed for lipid content (n=9), cellularity (n=28), total sulphated glycosaminoglycans (n=28), elastin content (n=9), and water content (n=56), using chloroform-methanol extraction, fluorimetry, the dimethylmethylene blue assay, and ion exchange chromatography, respectively.
  
  
  RESULTS
  Qualitatively, an increase in elastin and a decrease in fibronectin and GFAP were demonstrated when young tissue was compared with the elderly. Biochemical analysis of the ageing human lamina cribrosa demonstrated that elastin content increased from 8% to 28% dry tissue weight, total sulphated glycosaminoglycans decreased, and lipid content decreased from 45% to 25%. There were no significant changes in total cellularity or water content.
  
  
  CONCLUSIONS
  These alterations in composition may be indicative of the metabolic state of the lamina cribrosa as it ages, and may contribute to changes in mechanical integrity. Such changes may be implicated in the susceptibility of the elderly lamina cribrosa and also its response to glaucomatous optic neuropathy.
authors.affiliation: Department of Optometry and Vision Science, Cardiff University, UK.
authors.forename: J
authors.initials: J
authors.lastname: Albon
authors.forename: W S
authors.initials: WS
authors.lastname: Karwatowski
authors.forename: D L
authors.initials: DL
authors.lastname: Easty
authors.forename: T J
authors.initials: TJ
authors.lastname: Sims
authors.forename: V C
authors.initials: VC
authors.lastname: Duance
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D002648:Child; D002675:Child, Preschool; D003094:Collagen / Q000032:analysis*; D004549:Elastin / Q000032:analysis*; D005109:Extracellular Matrix / Q000737:chemistry*; D005353:Fibronectins / Q000032:analysis*; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006025:Glycosaminoglycans / Q000032:analysis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008055:Lipids / Q000032:analysis; D008875:Middle Aged; D009898:Optic Disk / Q000737:chemistry*
chemical_list: D005353:Fibronectins; D005904:Glial Fibrillary Acidic Protein; D006025:Glycosaminoglycans; D008055:Lipids; D003094:Collagen; D004549:Elastin