Skip to main content
. 2017 Jan 31;7:41768. doi: 10.1038/srep41768

Figure 4. ST266-induced signaling pathways contributing to RGC neuroprotection.

Figure 4

EAE mice were treated daily with intranasal PBS or ST266 beginning day 15 post-immunization through sacrifice (days 22, 30 or 42). Protein was isolated for Western blot analysis. Alternatively, optic nerves were stained with MitoSOX Red. Data represent mean ± SD levels from 3 mice/group. (A) ST266 increases day 22 retinal SIRT1 expression (*p < 0.05 vs. EAE). (B) ST266 increases day 22 retinal PGC1α expression (*p < 0.05 vs. EAE). By day 30, PGC1α expression in EAE retinas decreases (***p < 0.001 vs. controls), while ST266 still increases PGC1α (@p < 0.05 vs. EAE). (C) ST266 increases day 30 SDH expression in retina and optic nerves (@p < 0.05 vs. EAE). (D) Increased MitoSOX Red staining of superoxide in EAE optic nerves (***p < 0.001 vs. controls) on day 22 is reduced by ST266 (@@p < 0.01 vs. EAE). Images show MitoSOX Red staining in one optic nerve/group (original magnification X40) in (D,E). At day 42, increased MitoSOX Red staining in EAE optic nerves (**p < 0.01 vs controls) is further reduced by ST266 (@@p < 0.01 vs EAE). (F) Primary retinal cell cultures exposed to 5 μM staurosporine for 24 h show loss of Thy1+ RGCs (**p < 0.01 vs. controls), that is prevented by 24 h treatment with ST266 diluted 1:20 in medium (@@p < 0.01). 2 μM EX527 (SIRT1 inhibitor) blocks protective effects of ST266 (##p < 0.01). EX527 alone does not affect RGC survival (^^p < 0.01 vs. staurosporine +ST266 + EX527). N = 3–4 wells/culture condition. One of two experiments shown. (G) ST266 increases day 30 retinal pAKT expression (*p < 0.05 vs. EAE). (H) ST266 decreases retinal pPDK1 expression (*p < 0.05 vs. EAE). (I) ST266 (1:20) prevention (@p < 0.05) of staurosporine- induced RGC loss in primary retinal cultures (**p < 0.01 vs. controls) is blocked by 7 μM pAKT inhibitor X (^p < 0.05). pAKT inhibitor X alone does not affect RGC survival (@p < 0.05 vs staurosporine +ST266 + pAKT inhibitor X). N = 3–4 wells/culture condition. One of two experiments shown.