title: Matrix metalloproteinases and tissue inhibitors of metalloproteinases in the aqueous humour of patients with primary angle closure glaucoma - a quantitative study.
abstract: BACKGROUND
  Altered levels of specific matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in the aqueous humour of primary open-angle glaucoma (POAG) eyes have been described. In this study, levels of specific MMPs and TIMPs in the aqueous humour of primary angle-closure glaucoma (PACG) eyes were measured and compared with those of POAG as well as non-glaucoma control eyes.
  
  
  METHODS
  Aqueous humour from 16 PACG, 28 POAG and 27 control eyes were sampled during intraocular surgery. Levels of total protein, MMP-2, MMP-3, TIMP-1 and TIMP-2 were quantified by protein assay and enzyme immunoassay.
  
  
  RESULTS
  Total protein levels were significantly higher in PACG (0.426 ± 0.126 mg/ml, p = 0.043) and POAG (0.578 ± 0.360 mg/ml, p = 0.007) compared to controls (0.292 ± 0.192 mg/ml). The difference between PACG and POAG was not significant (p = 0.158). MMP-2 was significantly higher in PACG (p = 0.032) and POAG (p < 0.001) compared to controls. The difference between PACG and POAG was also not significant (p = 0.133). MMP-3 was significantly higher in POAG compared to controls (p = 0.002) and PACG (p = 0.029). The difference between PACG and controls was not significant (p = 0.962). TIMP-1 was significantly higher in PACG (p = 0.049) and POAG (p = 0.010) compared to controls. The difference between PACG and POAG was also not significant (p = 0.961). TIMP-2 was significantly higher in POAG (p = 0.004) compared to controls. The difference between PACG and either controls or POAG was not significant (p > 0.05). Although not statistically significant (p > 0.05), the MMP-2/TIMP-2 ratio was highest in PACG (2.83 ± 7.40), followed by POAG (1.38 ± 1.55) and controls (1.34 ± 3.05). Similarly, the MMP-2/TIMP-1 ratio was highest in PACG (1.50 ± 1.69), followed by POAG (1.40 ± 0.77) and controls (1.15 ± 0.92). The MMP-2 + MMP-3/TIMP-1 + TIMP-2 ratio was higher in PACG (0.83 ± 0.80) and POAG (0.82 ± 0.53) compared to controls (0.70 ± 0.63). In both POAG and PACG, there were no significant differences in the levels of total protein, MMP-2, MMP-3, TIMP-1 and TIMP-2 between patients on prostaglandin analogues and those not.
  
  
  CONCLUSIONS
  We found altered levels of MMPs and TIMPs as well as imbalance of MMP:TIMP ratios in the aqueous humour of PACG eyes that were different from POAG and non-glaucoma control eyes.
authors.forename: Angeline D C
authors.initials: AD
authors.lastname: Nga
authors.forename: Soon-Lek
authors.initials: SL
authors.lastname: Yap
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, University Malaya, Kuala Lumpur 50603, Malaysia. amir@ummc.edu.my.
authors.forename: Amir
authors.initials: A
authors.lastname: Samsudin
authors.forename: Puteri S
authors.initials: PS
authors.lastname: Abdul-Rahman
authors.forename: Onn H
authors.initials: OH
authors.lastname: Hashim
authors.forename: Zahari
authors.initials: Z
authors.lastname: Mimiwati
mesh_terms: D000368:Aged; D001082:Aqueous Humor / Q000378:metabolism*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000378:metabolism*; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism*; D008875:Middle Aged; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism*
chemical_list: D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D019278:Matrix Metalloproteinase 3; D020778:Matrix Metalloproteinase 2