Abstract
Purpose: :
Brain-derived neurotrophic factor (BDNF) has been shown to induce neuroprotective and antiapoptotic processes to improve neurological function in animal models of stroke and retinal detachment (RD). Intravitreal injection of BDNF may provide a therapeutic approach to inhibit retinal neuronal cell death and loss of vision observed in RD. Little is known about endogenous intravitreal BDNF in normal human eyes or RD patients. The purpose of this study is to establish BDNF levels in vitreous samples collected from rhegmatogenous retinal detachment (RRD) patients and human eyes without disease.
Methods: :
Undiluted vitreous samples were collected from RRD patients prior to pars plana vitrectomy, and stored immediately at -80ºC. Vitreous collected from fresh donor eyes without documented eye disease served as controls. The concentration of total protein within each vitreous sample was determined with a BCA assay kit. The vitreal BDNF concentration in RRD samples and controls were measured by enzyme-linked immunosorbent assay (ELISA), and normalized to total protein concentration. The BDNF/total protein ratios were statistically analyzed using a 2-tailed t-test.
Results: :
The BDNF levels detected within the vitreous samples ranged from 4.8pg/ml to 11.8pg/ml. The BDNF/total protein ratio in the RRD group was 2.49±0.44 and found to be significantly higher than that of the control group which was 1.42±0.61, (p=0.042).
Conclusions: :
BDNF is present at low levels within normal human vitreous. A higher level of intravitreal BDNF in RRD patients may indicate a natural cell survival response initiated by the RRD. Increasing the vitreal levels of BDNF, either exogenously or endogenously, may prove beneficial for protecting neurons in a detached retina as well as retinal neurodegenerative disorders.
Keywords: retinal detachment • vitreous • neuropeptides