Fig. 3

Lowering general MMP activity after ONC does not influence RGC survival, nor reduces retinal thickness. A,B: Representative confocal images of retinal sections immunostained for activated caspase-3 reveal no apoptotic cells in GM6001-treated eyes at 2 dpi (A) and only a limited number of apoptotic cells in the RGCL at 7 dpi (see arrows) (B). C-F: Magnifications of an activated caspase-3 immunostaining on retinal sections of PBS-, DMSO-, and GM6001-treated fish indicate a similar amount of apoptotic RGCs at 7 dpi in the three conditions, while apoptosis is absent in UCC fish. Moreover, no obvious disruption of retinal structure, nor retinal thinning can be observed in GM6001-injected fish. DAPI (blue) was used as nuclear counterstain. G: Quantitative analysis of the ratio of activated caspase-3⁺ cells/DAPI⁺ cells in the RGCL reveals no difference between PBS-, DMSO-, and GM6001-treated fish at 7 dpi. Data represent five fish per group and are shown as mean ± SEM. H: Likewise, the number of DAPI⁺ cells per 100 µm of RGCL was similar in all conditions, both at 2 and 7 dpi, confirming that no significant cell loss is induced after ONC/treatment. Data represent five fish per group and are shown as mean ± SEM. I: A quantitative analysis on retinal sections did not reveal any significant differences in retinal thickness of uninjected, PBS-, DMSO-, and GM6001-treated fish at 7 dpi. Six retinal sections were analyzed per fish, using five fish per condition. Data are shown as mean ± SEM. Dpi, days postinjury; PBS, phosphate-buffered saline; DMSO, dimethyl sulfoxide; NFL, nerve fiber layer; RGCL, retinal ganglion cell layer; IPL, inner plexiform layer; INL, inner nuclear layer; OPL, outer plexiform layer; ONL, outer nuclear layer; PRL, photoreceptor layer. Scale bars = 50 µm in A,B; 20 µm in C-F.