First Author | Jiang H | Year | 2016 |
Journal | J Neurochem | Volume | 136 |
Issue | 1 | Pages | 186-93 |
PubMed ID | 26485193 | Mgi Jnum | J:228514 |
Mgi Id | MGI:5707539 | Doi | 10.1111/jnc.13400 |
Citation | Jiang H, et al. (2016) Loss-of-function mutation of serine racemase attenuates excitotoxicity by intravitreal injection of N-methyl-D-aspartate. J Neurochem 136(1):186-93 |
abstractText | Convincing data demonstrate that D-serine, a racemized product of serine racemase (SR), contributes to neurotoxicity. Furthermore, a line of evidence suggests that SR/D-serine contributes to retinal neurodegeneration in a diabetic retinopathy rat model and diabetic retinopathy patients. However, the connection between SR/D-serine and retinal neurodegeneration remains unclear. Herein, we report that intravitreal injection of N-methyl-D-aspartate (NMDA) induces excitotoxicity in rodent retina; this retinal neurodegeneration was attenuated in retina carrying a loss-of-function of mutation in Srr, the gene for SR, termed Srr(ochre269) . Under the condition of NMDA injection, either posterior pole or middle - but not peripheral - retina from Srr(ochre269) mice was found to retain more retinal ganglion cells (RGC) than the counterpart from w/t (RGCs were identified with retrograde labeling). Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining further demonstrated reduced RGC apoptosis from Srr(ochre269) compared to w/t mice under the condition of NMDA injection. Collectively, our studies demonstrate a pivotal role of SR/D-serine in retinal neurotoxicity. We demonstrated that loss-of-function mutation of the gene encoding serine racemase significantly attenuates excitotoxicity in retina; excitotoxicity accounts for retinal ganglion cell (RGC) demise in diabetic retinopathy (DR). We think that our findings deepen the current knowledge of the mechanisms of RGC degeneration. |