Increased tumor necrosis factor-α, cleaved caspase 3 levels and insulin receptor substrate-1 phosphorylation in the ß1-adrenergic receptor knockout mouse.
Mol Vis
; 17: 1822-8, 2011.
Article
em En
| MEDLINE
| ID: mdl-21850156
ABSTRACT
PURPOSE:
To investigate the role of ß1-adrenergic receptors on insulin like growth factor (IGF)-1 receptor signaling and apoptosis in the retina using ß1-adrenergic receptor knockout (KO) mice.METHODS:
Western blotting and enzyme-linked immunosorbent assay analyses were done on whole retinal lysates from ß1-adrenergic receptor KO mice and wild-type littermates. In addition, vascular analyses of degenerate capillaries and pericyte ghosts were done on the retina of the ß1-adrenergic receptor KO mice versus littermates.RESULTS:
Lack of ß1-adrenergic receptors produced a significant increase in both degenerate capillaries and pericyte ghosts. This was accompanied by an increase in cleaved caspase 3 and tumor necrosis factor α levels. IGF-1 receptor phosphorylation was not changed; however, protein kinase B (Akt) phosphorylation was significantly decreased. The decrease in Akt phosphorylation is likely caused by increased insulin receptor substrate-1 serine 307 (IRS-1(Ser307)) phosphorylation, which is inhibitory to IGF-1 receptor signaling.CONCLUSIONS:
These studies further support the idea that maintenance of ß-adrenergic receptor signaling is beneficial for retinal homeostasis. Loss of ß1-adrenergic receptor signaling alters tumor necrosis factor α and apoptosis levels in the retina, as well as Akt and IGF-1 receptor phosphorylation. Since many of these same changes are observed in the diabetic retina, these data support that novel ß-adrenergic receptor agents may provide additional avenues for therapeutics.
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Base de dados:
MEDLINE
Assunto principal:
Retina
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Transdução de Sinais
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Fator de Necrose Tumoral alfa
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Receptores Adrenérgicos beta 1
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Retinopatia Diabética
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Caspase 3
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Proteínas Substratos do Receptor de Insulina
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article