Exendin-4 alleviates high glucose-induced rat mesangial cell dysfunction through the AMPK pathway.
Cell Physiol Biochem
; 33(2): 423-32, 2014.
Article
em En
| MEDLINE
| ID: mdl-24556697
ABSTRACT
BACKGROUND/AIMS:
Glucagon-like peptide-1 (GLP-1), which counteracts insulin resistance in humans with type 2 diabetes, has been shown to ameliorate diabetic nephropathy in experimental models. However, the mechanisms through which GLP-1 modulates renal function remained illdefined. The present study investigated the putative mechanisms underlying effects of exendin-4, a GLP-1 analog, on mesangial cell proliferation and fibronectin.METHODS:
Rat mesangial cells (MCs) were treated with exendin-4 under high glucose conditions. AMP-activated protein kinase (AMPK) inhibitors (compound C) and agonists (AICAR) were used to analyze the role of this kinase. Cell proliferation was measured using a MTT assay. Fibronectin expression and AMPK-signaling pathway activity were assessed using ELISA and Western blotting, respectively. The production of matrix metalloproteinase (MMP)-2 and tissue inhibitors of metalloproteinases (TIMP)-2 was evaluated using quantitative real-time RT-PCR.RESULTS:
Exendin-4 inhibited cell proliferation and fibronectin secretion in high glucose-induced MCs. It also caused phosphorylation of AMPK and subsequently increased the ratio of MMP-2 to TIMP-2, which resulted in the degradation of fibronectin. Exendin-4 reversed extracellular signal-regulated kinase (ERK) phosphorylation and enhanced expression of mammalian target of rapamycin (mTOR) in MCs. Moreover, the activation of the AMPK pathway by exendin-4 was induced by AICAR, which was inhibited by compound C.CONCLUSION:
Exendin-4 exerts an inhibitory effect on cell proliferation and fibronectin secretion in rat MCs, partly through AMPK activation. These results may explain some of the beneficial effects of exendin-4 on the kidney.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Edulcorantes
/
Peçonhas
/
Sistema de Sinalização das MAP Quinases
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Nefropatias Diabéticas
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Proteínas Quinases Ativadas por AMP
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Glucose
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Hipoglicemiantes
Limite:
Animals
Idioma:
En
Revista:
Cell Physiol Biochem
Assunto da revista:
BIOQUIMICA
/
FARMACOLOGIA
Ano de publicação:
2014
Tipo de documento:
Article