Vitreous levels of IGF-I, IGF binding protein 1, and IGF binding protein 3 in proliferative diabetic retinopathy: a case-control study.

摘要: OBJECTIVE: To evaluate vitreous levels of IGF-I and its binding proteins IGFBP-1 IGFBP-3 in patients with proliferative diabetic retinopathy (PDR). Because intravitreal are elevated PDR due to the disruption blood-retinal barrier, we have corrected vitreal IGFBPs by total avoid this confounding factor. RESEARCH DESIGN AND METHODS: We compared 21 (group A) 13 nondiabetic B) whom a vitrectomy was performed. Both groups were matched age, serum IGF-I, IGFBP-1, levels. Serum measured immunological methods. Vitreal assessed turbidimetric method. RESULTS: group A (median 1.35 ng/ml [range 0.3-8.7]) comparison B 0.25 0-1.38]), P<0.001. After adjusting [ratio (ng/ml)/protein (mg/ml)], differences remain significant (P<0.005). also (IGFBP-1: A, median 1.6 0.6-20.7]; B, 0.4 0.3-1.9], IGFBP-3: 102.6 53.9-350.8]; 29.0 3.2-87.8], P<0.001). However, when ratio IGFBP/protein considered, not significant. CONCLUSIONS: Intraocular synthesis contributes concentrations found PDR. By contrast, unspecific increase is main factor explaining patients.