Session Title: Quick Fire Free Paper Session 02
Session Date/Time: Thursday 26/09/2013 | 14:30-16:00
Paper Time: 15:20
Venue: Hall G1 (Level 2)
First Author: G.Bikbova JAPAN
Co Author(s): O. Toshiyuki S. Yamamoto
To determine whether neurorptective and regenerative effect of neurotrophin-4 (NT-4) is correlated with the reduction of caspase-9 and AIF expression in rat retinas exposed to AGEs.
Department of Ophthalmology and Visual Science, Chiba University
Retinal explants of 4 adult SD rats were three-dimensionally cultured in collagen gel and were incubated either in; 1) serum free control culture media, 2) 10 μg/ml glucose-AGE-BSA media, 3) 10 μg/ml glycolaldehyde-AGE-BSA media, 4) 10 μg/ml glyceraldehyde-AGE-BSA media, 5) glucose-AGE+100ng/ml NT-4 media, 6) glycol-AGE+100ng/ml NT-4 media, or 7) glycer-AGE+100 ng/ml NT-4 supplemented culture media. After 7 days, the number of regenerating neurites from the explants was counted under a phase-contrast microscope. After counting, retinal explants were fixed, cryosectioned, and stained by TUNEL and DAPI. The ratio of TUNEL-positive cells to the number of DAPI-staining nuclei in the ganglion cell layer was calculated. Immunohistochemistry for the active form of caspase 9 and apoptosis-inducing factor (AIF) was performed. Statistical analysis was performed by one-way ANOVA.
In retinas incubated with AGEs (glucose-AGE, glycol-AGE, and glycer-AGE), the numbers of regenerating neurites were fewer than in retinas without AGE (P=0.0033, P=0.0044, P=0.0238) and the numbers of TUNEL-positive cells (P < 0.0001, P < 0.0001, P < 0.0001) and caspase -9 (P < 0.0001; P < 0.0001; P < 0.0001) and AIF immunopositive cells (P =0.0004, P =0.0002; P=0.056) in the ganglion cell layer were higher than in control media. NT-4 supplementation increased, the numbers of regenerating neuritis (P<0.0001, P<0.0001, P<0.0001). The numbers of TUNEL-positives cells (P<0.001, P=0.005, P=0.0003) caspase -9 (P<0.001, P<0.005, P<0.001) and AIF (P=0.026, P=0.026, P=0.016) immunopositive cells were significantly lower than those in glucose-AGE without NT-4 in glycol-AGE without NT-4 and in glycer-AGE without NT-4.
Caspase-dependent and caspase-independent cell death pathways are associated with retinal neuronal cell death in low dose AGE-BSA exposed rat retinas. NT-4 showed strong regenerative and neuroprotective effect.