Purpose: To investigate the concentrations of transforming growth factor (TGF)-β2, matrix metalloproteinase (MMP)-2, and tissue inhibitor of metalloproteinase (TIMP)-2 in the vitreous of patients with high myopia.
Methods: Twenty-six patients with high myopia (HM) who received vitrectomy for macular retinoschisis or macular hole were enrolled in this prospective study. Twenty-six patients with idiopathic macular hole or macular epiretinal membrane were chosen as a control group. Vitreous samples were obtained during the vitrectomy surgery. The levels of TGF-β2、MMP-2、TIMP-2 in the vitreous samples were measured by enzyme-linked immunosorbent assay. The MMP activity was determined by a fluorometric assay.
Results: There was no significant difference in the vitreous level of TGF-β2 between HM (1.64 ± 0.38 ng/ml) and the control group (1.56 ± 0.32 ng/ml, p = 0.56). The vitreous levels of MMP-2 in HM (32.40 ± 14.90 ng/ml) were significantly higher than in the control group (21.42 ± 6.74 ng/ml, p < 0.01). The ratio of MMP-2/TIMP-2 was significantly elevated in the vitreous samples from HM (0.61 ± 0.19), compared to the control group (0.48 ± 0.11, p < 0.05). The MMP activity was also significantly elevated in the vitreous samples from HM (4,030.8 ± 1,257.3 FIU), compared to the control group (3,245.8 ± 835.6 FIU, p < 0.05).
Conclusions: The elevated MMP/TIMP ratio and MMP activity may play a role in the pathogenesis of human high myopia. Large prospective studies are needed to further investigate the effect of MMPs in the pathogenesis of human high myopia.