The retinal macroglia in hypercholesterolemic rabbits: neuroprotective effect of a non‐lipid‐lowering statin dose

Abstract

PurposeTo evaluate the pleiotropic effects of low‐dose statins in the morphology of retinal macroglia in long‐term hypercholesterolemic rabbits and to quantify treatment‐induced astrocyte changes.MethodsNew Zealand rabbits were split into three groups: Control (G0; n = 10), fed a standard diet; Hypercholesterolemic (G1; n = 8), fed a 0.5% cholesterol‐enriched diet for 8 months; and Statins (G2; n = 8), fed a 0.5% cholesterol‐enriched diet for 8 months together with the administration of fluvastatin sodium or pravastatin sodium at a dose of 2 mg/Kg/day each. Eyes were processed for immunohistochemistry using anti‐GFAP. The retinal area occupied by astrocytes was quantified.ResultsMüller cells and astrocytes were reactive in G1 and G2. In contrast with G1, no GFAP+ Müller cells forming glial scar‐like structures were detected in G2. In comparison with G0: i) the retinal area occupied by astrocytes associated with the nerve bundles was statistically reduced in G1 (p < 0.006); however, no significant changes were observed in G2; and ii) the retinal area occupied by perivascular astrocytes in G1 was significantly reduced (p < 0.003) due to the disappearance of perivascular astrocytes from the vessels, but significantly increased in G2 (p < 0.030), given that perivascular astrocytes did not disappear from the vessels and were reactive.ConclusionsDespite serum cholesterol values remained unchanged, treatment with low‐dose statins preserved retinal macroglia. The pleiotropic effects of the statins seem to help to prevent astroglial death induced by hypercholesterolemia.