To investigate Wnt3a and vascular endothelial growth factor (VEGF) levels in the vitreous fluid of patients with proliferative diabetic retinopathy (PDR) and to examine their correlation with PDR activity.
Vitreous samples from 45 eyes with PDR and 28 eyes with nondiabetic macular disease were collected. Active PDR was present in 24 patients and inactive PDR in 21 patients, according to retinal neovascularization. The Wnt3a and VEGF level of vitreous fluid samples were measured by enzyme-linked immunosorbent assay.
Comparison revealed that mean intravitreal levels of Wnt3a increased significantly in PDR eyes compared with control eyes (13.55 ng/mL vs. 1.57 ng/mL, P < 0.001). The mean VEGF concentrations in the vitreous fluid of patients with PDR were also higher than those in nondiabetic controls, with the values being 723.21 pg/mL and 20.81 pg/mL, respectively (P < 0.001). In addition, vitreous concentrations of Wnt3a and VEGF were significantly higher in active PDR than in eyes with inactive PDR (P = 0.016 and P = 0.008, respectively). Furthermore, a significant positive correlation was detected between Wnt3a and VEGF levels in the vitreous.
Intravitreous levels of Wnt3a and VEGF in patients with PDR are increased and correlated mutually. Wnt3a may be an important player in the development of diabetic retinopathy and its activity in vitreous fluid can be biomarker of PDR.
Proliferative diabetic retinopathy (PDR) is a major cause of visual impairment and its mechanism remains unclear till date. In this article, the authors conduct a study to examine the concentration of Wnt3a in vitreous fluid and investigate the relationship between intravitreal levels of Wnt3a and VEGF. To the best of the author's knowledge, this study is the first to analyze the expression of Wnt3a in the vitreous of patients with PDR. The activity of Wnt3a in vitreous fluid can be a biomarker of PDR.
*Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Science Key Laboratory, Beijing, China;
†Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China;
‡Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China; and
§Clinical Lab of Tissue and Cell Research Center, Department of Biotech Treatment, Logistics College of Chinese People's Armed Police Force, Tianjin, China.
Reprint requests: Xiaoyan Peng, MD, PhD, Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Science Key Laboratory, 17 Hougou Lane, Chongnei Street, Beijing 100005, China; e-mail: email@example.com
None of the authors have any financial/conflicting interests to disclose.