Reduced Scleral TIMP-2 Expression Is Associated With Myopia Development: TIMP-2 Supplementation Stabilizes Scleral Biomarkers of Myopia and Limits Myopia Development

Invest Ophthalmol Vis Sci. 2017 Apr 1;58(4):1971-1981. doi: 10.1167/iovs.16-21181.


Purpose: The purpose of this study was to determine the endogenous regulation pattern of tissue inhibitor of metalloproteinase-2 (TIMP-2) in the tree shrew sclera during myopia development and investigate the capacity of exogenous TIMP-2 to inhibit matrix metalloproteinase-2 (MMP-2) in vitro and both scleral collagen degradation and myopia development in vivo.

Methods: TIMP-2 expression in the sclera during myopia development was assessed using polymerase chain reaction. In vitro TIMP-2 inhibition of MMP-2 was investigated using a gelatinase activity plate assay and zymography. Tree shrews were injected with a collagen precursor before undergoing monocular form deprivation and concurrent daily subconjunctival injections of either TIMP-2 or vehicle to the form-deprived eye. In vivo ocular biometry changes were monitored, and scleral tissue was collected after 12 days and assayed for collagen degradation.

Results: The development of myopia was associated with a mean reduction in TIMP-2 mRNA expression after 5 days of form deprivation (P < 0.01). Both activation and activity of MMP-2 were inhibited by TIMP-2 with an IC50 of 10 to 20 and 2 nM, respectively. In vivo exogenous addition of TIMP-2 significantly reduced myopia development (P < 0.01), due to reduced vitreous chamber elongation (P < 0.01). In vivo TIMP-2 treatment also significantly inhibited posterior scleral collagen degradation relative to vehicle-treated eyes (P < 0.01), with levels similar to those in control eyes.

Conclusions: Myopia development in mammals is associated with reduced expression of TIMP-2, which contributes to increased degradative activity in the sclera. It follows that replenishment of this TIMP-2 significantly reduced the rate of both scleral collagen degradation and myopia development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Biomarkers / metabolism
  • Biometry
  • Cells, Cultured
  • Collagen / metabolism
  • Disease Models, Animal
  • Female
  • Fibroblasts / metabolism
  • Fibroblasts / pathology
  • Gene Expression Regulation, Developmental*
  • Matrix Metalloproteinase Inhibitors / therapeutic use
  • Myopia / drug therapy
  • Myopia / genetics*
  • Myopia / metabolism
  • RNA / genetics*
  • RNA, Messenger
  • Real-Time Polymerase Chain Reaction
  • Sclera / enzymology*
  • Tissue Inhibitor of Metalloproteinase-2 / biosynthesis
  • Tissue Inhibitor of Metalloproteinase-2 / genetics*
  • Tissue Inhibitor of Metalloproteinase-2 / therapeutic use*
  • Tupaia


  • Biomarkers
  • Matrix Metalloproteinase Inhibitors
  • RNA, Messenger
  • Tissue Inhibitor of Metalloproteinase-2
  • RNA
  • Collagen