A long-acting isomer of Ac-SDKP attenuates pulmonary fibrosis through SRPK1-mediated PI3K/AKT and Smad2 pathway inhibition.
IUBMB Life
; 72(12): 2611-2626, 2020 12.
Article
em En
| MEDLINE
| ID: mdl-33135306
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a progressive, life-threatening lung disease with a poor prognosis. N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a critical negative regulator of fibrosis development. However, it's extremely short half-life greatly limits its applications. Previously, we reported an Ac-SDKP analog peptide in which Asp and Lys residues were replaced with D-amino acids (Ac-SDD KD P). Ac-SDD KD P exhibits better resistance to angiotensin-1-converting enzyme (ACE)-mediated degradation and a longer half-life than Ac-SDKP in rat and human sera. The objective of this study was to explore the potential application of Ac-SDD KD P for the treatment of IPF and to clarify the underlying mechanisms. We found that Ac-SDD KD P exerted similar antifibrotic effects as Ac-SDKP on human fetal lung fibroblast-1 (HFL-1) proliferation, α-smooth muscle actin (α-SMA), collagen I and collagen III expression, and Smad-2 phosphorylation in vitro. In vivo, Ac-SDD KD P exhibited significantly greater protective effects against bleomycin-induced pulmonary fibrosis than Ac-SDKP in mice. α-SMA, CD45, collagen I and collagen III expression, and Smad-2 phosphorylation were significantly decreased in the lungs of Ac-SDD KD P-treated but not Ac-SDKP-treated mice. Furthermore, a pull-down experiment was used to screen for molecules that interact with Ac-SDKP. Co-immunoprecipitation (Co-IP) and computer-based molecular docking experiments demonstrated an interaction between Ac-SDKP or Ac-SDD KD P (Ac-SDKP/Ac-SDD KD P) and serine/arginine-rich protein-specific kinase 1 (SRPK1) that caused inhibition SRPK1-mediated phosphatidylinositol-3 kinase/ serine/threonine kinase (PIK3/AKT) signaling pathway activation and Smad2 phosphorylation and thereby attenuated lung fibrosis. Our data suggest that long-acting Ac-SDD KD P may potentially be an effective drug for the treatment of pulmonary fibrosis. The interacting molecule and antifibrotic mechanism of Ac-SDKP/Ac-SDD KD P were also identified, providing an experimental and theoretical foundation for the clinical application of the drug.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligopeptídeos
/
Fibrose Pulmonar
/
Proteínas Serina-Treonina Quinases
/
Fosfatidilinositol 3-Quinases
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Proteínas Proto-Oncogênicas c-akt
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Proteína Smad2
/
Pulmão
Tipo de estudo:
Etiology_studies
Limite:
Animals
/
Female
/
Humans
Idioma:
En
Revista:
IUBMB Life
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China