Ferroptosis drives photoreceptor degeneration in mice with defects in all-trans-retinal clearance.
J Biol Chem
; 296: 100187, 2021.
Article
in En
| MEDLINE
| ID: mdl-33334878
ABSTRACT
The death of photoreceptor cells in dry age-related macular degeneration (AMD) and autosomal recessive Stargardt disease (STGD1) is closely associated with disruption in all-trans-retinal (atRAL) clearance in neural retina. In this study, we reveal that the overload of atRAL leads to photoreceptor degeneration through activating ferroptosis, a nonapoptotic form of cell death. Ferroptosis of photoreceptor cells induced by atRAL resulted from increased ferrous ion (Fe2+), elevated ACSL4 expression, system Xc- inhibition, and mitochondrial destruction. Fe2+ overload, tripeptide glutathione (GSH) depletion, and damaged mitochondria in photoreceptor cells exposed to atRAL provoked reactive oxygen species (ROS) production, which, together with ACSL4 activation, promoted lipid peroxidation and thereby evoked ferroptotic cell death. Moreover, exposure of photoreceptor cells to atRAL activated COX2, a well-accepted biomarker for ferroptosis onset. In addition to GSH supplement, inhibiting either Fe2+ by deferoxamine mesylate salt (DFO) or lipid peroxidation with ferrostatin-1 (Fer-1) protected photoreceptor cells from ferroptosis caused by atRAL. Abca4-/-Rdh8-/- mice exhibiting defects in atRAL clearance is an animal model for dry AMD and STGD1. We observed that ferroptosis was indeed present in neural retina of Abca4-/-Rdh8-/- mice after light exposure. More importantly, photoreceptor atrophy and ferroptosis in light-exposed Abca4-/-Rdh8-/- mice were effectively alleviated by intraperitoneally injected Fer-1, a selective inhibitor of ferroptosis. Our study suggests that ferroptosis is one of the important pathways of photoreceptor cell death in retinopathies arising from excess atRAL accumulation and should be pursued as a novel target for protection against dry AMD and STGD1.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Retinaldehyde
/
Lipid Peroxidation
/
Photoreceptor Cells, Vertebrate
/
Ferroptosis
/
Macular Degeneration
Limits:
Animals
Language:
En
Journal:
J Biol Chem
Year:
2021
Document type:
Article
Affiliation country:
China