[Progress in studies of effects on brain-derived neurotrophic factor in degenerative fundus disease].

Degenerative fundus diseases are a group of outer retinal disease caused by dysfunction of photoreceptors, some of which have the inner layer defection. Brain-derived neurotrophic factor (BDNF) has been shown to play a key role in the neuronal survival, which accomplishes its protection via receptors, including a low affinity p75 and a high affinity tyrosine kinase receptor TrkB, retinal growth cone filopodia and cofactor of Zinc. It is proved that BDNF can induce differentiation of stem cells and retinal progenitor, in case for the effective retinal transplantation. The protection by BDNF has also been observed through the interaction with retinal neurons such as photoreceptors, bipolar cells, horizontal neurons, ganglion cells and dopaminergic cells, as well as other cells of eyes. Furthermore, BDNF has been used to attenuate the injuries of optic nerve and the application of BDNF combined with other neurotrophic factors and drugs also manifests a certain efficiency.

Effect of brain-derived neurotrophic factor on c-jun expression in the rd mouse retina.

AIM: To determine the location of c-jun protein, dynamic changes in c-jun mRNA and protein expression, and ultrastructure characteristics in the rd mouse retina, following a single dose of brain-derived neurotrophic factor (BDNF) in a short period of time. METHODS: A single intravitreal injection of BDNF at two dosages (25µg/L or 50µg/L) was given to the right eye of the rd mouse at age 2 and 3 weeks respectively. Two weeks after injection, the location of c-jun protein in the retina was observed by immunofluorescence detection, c-jun mRNA and protein expression in retinas were detected by quantitative real time polymerase chain reaction (RT-PCR) and western immunoblotting analysis, ultrastructure characteristics of retinas were detected by transmission electron microscope (TEM) observation. RESULTS: c-jun protein was expressed in the inner nuclear layer (INL) of retina. BDNF at two dosages (25µg/L and 50µg/L) increased c-jun mRNA expression at PN-4 weeks respectively (P(1)=0.019, P(2)=0.021). 50µg/L BDNF increased c-jun protein expression at PN-4 weeks (P =0.000). The retinal ultrastructure was improved. CONCLUSION: The effects of BDNF exerts on the c-jun expression in the retina are dose-dependent and time-dependent, which may mediate photoreceptor rescue indirectly in the pathological process of retinitis pigmentosa (RP) at early stage.