Complement component C3 plays a critical role in protecting the aging retina in a murine model of age-related macular degeneration.
Am J Pathol
; 183(2): 480-92, 2013 Aug.
Article
em En
| MEDLINE
| ID: mdl-23747511
ABSTRACT
Complement component C3 is the central complement component and a key inflammatory protein activated in age-related macular degeneration (AMD). AMD is associated with genetic variation in complement proteins that results in enhanced activation of C3 through the complement alternative pathway. These include complement factor H (CFH), a negative regulator of C3 activation. Both C3 inhibition and/or CFH augmentation are potential therapeutic strategies in AMD. Herein, we examined retinal integrity in aged (12 months) mice deficient in both factors H and C3 (CFH(-/-).C3(-/-)), CFH alone (CFH(-/-)), or C3 alone (C3(-/-)), and wild-type mice (C57BL/6). Retinal function was assessed by electroretinography, and retinal morphological features were analyzed at light and electron microscope levels. Retinas were also stained for amyloid ß (Aß) deposition, inflammation, and macrophage accumulation. Contrary to expectation, electroretinograms of CFH(-/-).C3(-/-) mice displayed more severely reduced responses than those of other mice. All mutant strains showed significant photoreceptor loss and thickening of Bruch's membrane compared with wild-type C57BL/6, but these changes were greater in CFH(-/-).C3(-/-) mice. CFH(-/-).C3(-/-) mice had significantly more Aß on Bruch's membrane, fewer macrophages, and high levels of retinal inflammation than the other groups. Our data show that both uncontrolled C3 activation (CFH(-/-)) and complete absence of C3 (CFH(-/-).C3(-/-) and C3(-/-)) negatively affect aged retinas. These findings suggest that strategies that inhibit C3 in AMD may be deleterious.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Retina
/
Complemento C3
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Degeneração Macular
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article