TY - JOUR
T1 - Vitreous TIMP-1 levels associate with neovascularization and TGF-β2 levels but not with fibrosis in the clinical course of proliferative diabetic retinopathy
AU - Van Geest, Rob J.
AU - Klaassen, Ingeborg
AU - Lesnik-Oberstein, Sarit Y.
AU - Tan, H. Stevie
AU - Mura, Marco
AU - Goldschmeding, Roel
AU - Van Noorden, Cornelis J.F.
AU - Schlingemann, Reinier O.
N1 - Funding Information: Acknowledgements This study was supported by grant 2005.00.042 from the Diabetes Fonds Nederland. The preparation of the manuscript by Monique Arendse is gratefully acknowledged.
PY - 2013/3
Y1 - 2013/3
N2 - In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and CCN2 (connective tissue growth factor; CTGF) cause blindness by neovascularization and subsequent fibrosis. This angio-fibrotic switch is associated with a shift in the balance between vitreous levels of CCN2 and VEGF in the eye. Here, we investigated the possible involvement of other important mediators of fibrosis, tissue inhibitor of metalloproteinases (TIMP)-1 and transforming growth factor (TGF)-β2, and of the matrix metalloproteinases (MMP)-2 and MMP-9, in the natural course of PDR. TIMP-1, activated TGF-β2, CCN2 and VEGF levels were measured by ELISA in 78 vitreous samples of patients with PDR (n = 28), diabetic patients without PDR (n = 24), and patients with the diabetes-unrelated retinal conditions macular hole (n = 10) or macular pucker (n = 16), and were related to MMP-2 and MMP-9 activity on zymograms and to clinical data, including degree of intra-ocular neovascularization and fibrosis. TIMP-1, CCN2 and VEGF levels, but not activated TGF-β2 levels, were significantly increased in the vitreous of diabetic patients, with the highest levels in PDR patients. CCN2 and the CCN2/VEGF ratio were the strongest predictors of degree of fibrosis. In diabetic patients with or without PDR, activated TGF-β2 levels correlated with TIMP-1 levels, whereas in PDR patients, TIMP-1 levels, MMP-2 and proMMP-9 were associated with degree of neovascularization, like VEGF levels, but not with fibrosis. We confirm here our previous findings that retinal fibrosis in PDR patients is significantly correlated with vitreous CCN2 levels and the CCN2/VEGF ratio. In contrast, TIMP-1, MMP-2 and MMP-9 appear to have a role in the angiogenic phase rather than in the fibrotic phase of PDR.
AB - In proliferative diabetic retinopathy (PDR), vascular endothelial growth factor (VEGF) and CCN2 (connective tissue growth factor; CTGF) cause blindness by neovascularization and subsequent fibrosis. This angio-fibrotic switch is associated with a shift in the balance between vitreous levels of CCN2 and VEGF in the eye. Here, we investigated the possible involvement of other important mediators of fibrosis, tissue inhibitor of metalloproteinases (TIMP)-1 and transforming growth factor (TGF)-β2, and of the matrix metalloproteinases (MMP)-2 and MMP-9, in the natural course of PDR. TIMP-1, activated TGF-β2, CCN2 and VEGF levels were measured by ELISA in 78 vitreous samples of patients with PDR (n = 28), diabetic patients without PDR (n = 24), and patients with the diabetes-unrelated retinal conditions macular hole (n = 10) or macular pucker (n = 16), and were related to MMP-2 and MMP-9 activity on zymograms and to clinical data, including degree of intra-ocular neovascularization and fibrosis. TIMP-1, CCN2 and VEGF levels, but not activated TGF-β2 levels, were significantly increased in the vitreous of diabetic patients, with the highest levels in PDR patients. CCN2 and the CCN2/VEGF ratio were the strongest predictors of degree of fibrosis. In diabetic patients with or without PDR, activated TGF-β2 levels correlated with TIMP-1 levels, whereas in PDR patients, TIMP-1 levels, MMP-2 and proMMP-9 were associated with degree of neovascularization, like VEGF levels, but not with fibrosis. We confirm here our previous findings that retinal fibrosis in PDR patients is significantly correlated with vitreous CCN2 levels and the CCN2/VEGF ratio. In contrast, TIMP-1, MMP-2 and MMP-9 appear to have a role in the angiogenic phase rather than in the fibrotic phase of PDR.
KW - CCN2
KW - Diabetic retinopathy
KW - Fibrosis
KW - MMP-2
KW - MMP-9
KW - Neovascularization
KW - TGF-β
KW - TIMP-1
KW - VEGF
UR - http://www.scopus.com/inward/record.url?scp=84874929596&partnerID=8YFLogxK
U2 - https://doi.org/10.1007/s12079-012-0178-y
DO - https://doi.org/10.1007/s12079-012-0178-y
M3 - Article
C2 - 23054594
SN - 1873-9601
VL - 7
SP - 1
EP - 9
JO - Journal of cell communication and signaling
JF - Journal of cell communication and signaling
IS - 1
ER -