Suppression of VEGF and Decrease in Vascular Leakage by Pyridoxal 5'-Phosphate in Diabetic Rats. |
In Hwan Hong, Hyeong Gon Yu, Sung Pyo Park |
1Department of Ophthalmology, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea. sungpyo@hanafos.com 2Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea. 3Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea. |
당뇨 쥐에서 Vitamin B6 (PLP)의 망막혈관누출 감소와 혈관내피성장인자의 억제 효과 |
홍인환1⋅유형곤2,3⋅박성표1 |
Department of Ophthalmology, Kangdong Sacred Heart Hospital, Hallym University College of Medicine1, Seoul, Korea Department of Ophthalmology, Seoul National University College of Medicine2, Seoul, Korea Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute3, Seoul, Korea |
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Abstract |
PURPOSE The authors of the present study investigated whether pyridoxal 5'-phosphate (PLP), an active coenzyme of vitamin B6, could inhibit the development of diabetic retinopathy in streptozotocin (STZ)-induced diabetic rats. METHODS: Seven-week-old Spraque-Dawley rats (n = 20) were used in the present study. STZ (70 mg/kg) was injected intraperitoneally to induce diabetes. Blood glucose and body weight were monitored. Intraperitoneal injections of 5 microg and 50 microg PLP were administered every two days from the second week of induced diabetes. During the third week of PLP injections, the concentration level of plasma homocysteine was measured. In addition, functional status was examined by vitreous fluorophotometer and anatomical status by vascular endothelial growth factor (VEGF) staining in the retina. RESULTS: Based on vitreous fluorophotometry examination, the PLP injection group proved to have a lower level of fluorescein concentration in the vitreous. Additionally, immunohistochemical staining revealed down-regulation of VEGF expression in the PLP group. In addition, the PLP group had a lower plasma homocysteine concentration. However, an over-dosage injection of PLP did not appear to have any noticeable impact on the treatment of diabetes. CONCLUSIONS: PLP, an active coenzyme of vitamin B6, proved to have inhibitory effects on VEGF expression and vascular leakage in the diabetic rat retina. |
Key Words:
Diabetic retinopathy;Pyridoxal 5'-phosphate (PLP);Vascular endothelial growth factor (VEGF);Vitreous fluorophotometry |
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