title: Intravitreous high expression level of netrin-1 in patients with proliferative diabetic retinopathy.
abstract: OBJECTIVE
  To investigate the significance of netrin-1 and vascular endothelial growth factor (VEGF) in the pathogenesis of retinal angiogenesis, the levels of netrin-1 and VEGF in the vitreous fluid and serum of the proliferative diabetic retinopathy (PDR) and non-proliferative diabetic retinopathy (non-PDR) patients were measured. We then determined the netrin-1 and VEGF expression in the oxygen induced retinopathy (OIR) mice retinas.
  
  
  METHODS
  A total of 18 eyes from 18 patients were included in our study and 10 of them were collected from PDR patients and 8 from non-PDR patients. Undiluted vitreous fluid samples were collected during pars plana vitrectomy. Appropriate blood samples were collected if possible. Netrin-1 and VEGF levels in the vitreous fluid and plasma were determined by Enzyme-linked Immunosorbent Assays. OIR mice models were established, and netrin-1 and VEGF levels were determined by immunohistochemistry analysis.
  
  
  RESULTS
  The levels of netrin-1 and VEGF in the vitreous of PDR patients were significantly higher than those in the controls (Mediannetrin-1=509.94 vs. 85.91 pg/ml, P<0.001 and Median VEGF=762.60 vs. 77.52 pg pg/ml, P<0.001). Netrin-1 was mainly expressed in GCL and INL of the retina in mice. Both netrin-1 and VEGF were up-regulated in OIR mice.
  
  
  CONCLUSIONS
  Netrin-1 and VEGF levels were elevated in vitreous fluid of the PDR patients and the OIR mice retinas. Therefore, netrin-1 may play important roles in pathological retinal angiogenesis.
authors.affiliation: Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Jiaolian
authors.initials: J
authors.lastname: Liu
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Xia
authors.forename: Siqi
authors.initials: S
authors.lastname: Xiong
authors.forename: Yunzheng
authors.initials: Y
authors.lastname: Le
authors.forename: Huizhuo
authors.initials: H
authors.lastname: Xu
mesh_terms: D000818:Animals; D003930:Diabetic Retinopathy / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D051379:Mice; D009389:Neovascularization, Pathologic; D009414:Nerve Growth Factors / Q000378:metabolism*; D000075388:Netrin-1; D012160:Retina / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism
chemical_list: C000617351:NTN1 protein, human; D009414:Nerve Growth Factors; C000617353:Ntn1 protein, mouse; D025521:Tumor Suppressor Proteins; D042461:Vascular Endothelial Growth Factor A; D000075388:Netrin-1