Influence of high level TGF-beta1 on scleral thickness.
In order to explore the role of TGF-beta1 in scleral remodeling and the possible mechanism, the influence of high level TGF-beta1 on scleral thickness and the expression of MMP-2 and TIMP-2 was investigated in a TGF-beta1 transgenic mouse model. Alb/TGF-beta1 (Cys(223,225)Ser) TGF-beta1 transgenic mice were used as experimental subjects and non-transgenic littermates as controls. Plasma levels of TGF-beta1 were determined by ELISA. TGF-beta1, MMP-2 and TIMP-2 levels in sclera were detected by using Western blot. The thickness of posterior sclera was measured by computerized image analysis of a midsagittal section. Mean difference was analyzed with independent t-test. The results showed plasma levels of TGF-beta1 in transgenic mice were 1.68 times as much as that in the controls (P<0.01). TGF-beta1 levels in the sclera of transgenic mice were 2.68 times of the controls (P<0.01). Posterior scleral thickness in transgenic mice were significantly thicker than in the controls. There was no significant difference in the MMP-2 levels between transgenic mice and controls, but the TIMP-2 levels were increased significantly in transgenic mice as compared with those in the controls. It was suggested that high levels of TGF-beta1 in transgenic mice could result in the increased scleral thickness by inducing the expression of TIMP-2 to suppress the activity of MMP-2, finally inhibiting the degradation of collagen.
Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. hxliu136@163.com
Haixia
H
Liu
Nan
N
Xiang
Hong
H
Zhang
D000818:Animals; D006984:Hypertrophy / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009216:Myopia / Q000150:complications / Q000473:pathology; D012590:Sclera / Q000473:pathology*; D015422:Scleral Diseases / Q000209:etiology / Q000378:metabolism*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000097:blood*
D053773:Transforming Growth Factor beta1; D019716:Tissue Inhibitor of Metalloproteinase-2; D020778:Matrix Metalloproteinase 2; C522362:Mmp2 protein, mouse