Purpose:
To investigate the potential protective effects of introducingbrain-derived neurotrophic factor (BDNF) combining with Bcl-2gene into retinal ganglion cells (RGCs) in vivo by electroporationin adult Sprague-Dawley (SD) rats’ optic nerve transectionmodel.
Methods:
SD rats were randomly assigned to five groups: Group 1 (BDNF/Bcl-2,+/+), Group 2 (BDNF/Bcl-2, +/-), Group 3 (BDNF/Bcl-2,-/+), Group4 (BDNF/Bcl-2,-/-), Group 5 (control). The BDNF-GFP and Bcl-2-GFPfusion eukaryotic expressing plasmid was constructed and intravitreouslyinjected into the eyes of adult SD rats followed by in vivoelectroporation. One week after electroporation, the rats’optic nerve were transected in Group 1-4. The expression ofboth BDNF and Bcl-2 mRNA and protein were detected by RT-PCRand Western immunoblot analysis. The number of surviving RGCswas counted using the retrograde axonal tracer 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanineperchlorate(DiI) and the TdT-dUTP terminal nick-end labeling(TUNEL) method was used to detect the apoptotic RGCs at differenttime points after introduction of plasmid.
Results:
Group1-3 showed a significantly higher rescue ratio and a lowernumber of TUNEL-positive RGCs than did the control eyes at varioustime points, while Group 1 had the highest ratio and lowestnumber. The expression of BDNF was up-regulating when introducedcombining with Bcl-2 gene.
Conclusions:
These findings provide evidence that electroporation is an effectivemethod for gene transfer into RGCs and more effective rescueof RGCs can be achieved by BDNF combining with Bcl-2 gene transfectionwith electroporation.
Keywords: gene transfer/gene therapy • neuroprotection • ganglion cells