| First Author | Martín P | Year | 2014 |
| Journal | Am J Physiol Renal Physiol | Volume | 307 |
| Issue | 1 | Pages | F75-85 |
| PubMed ID | 24872318 | Mgi Jnum | J:211647 |
| Mgi Id | MGI:5575809 | Doi | 10.1152/ajprenal.00398.2013 |
| Citation | Martin P, et al. (2014) Relevant role of PKG in the progression of fibrosis induced by TNF-like weak inducer of apoptosis. Am J Physiol Renal Physiol 307(1):F75-85 |
| abstractText | TNF-like weak inducer of apoptosis (TWEAK) is an inflammatory cytokine that activates the FGF-inducible 14 receptor. Both TWEAK and the FGF-inducible 14 receptor are constitutively expressed in the kidney. TWEAK has been shown to modulate several biological responses, such as inflammation, proliferation, differentiation, and apoptosis, that contribute to kidney injury. However, the role of TWEAK in fibrosis and TWEAK-activated intracellular signaling pathways remain poorly understood. We tested the hypothesis that TWEAK can be a potent inducer of renal fibrosis by increasing transforming growth factor (TGF)-beta1 expression (a well-known switch in the fibrosis process) through PKG-I downregulation. We showed that in human mesangial cells, TWEAK increased TGF-beta1 expression and activity, leading to higher levels of the extracellular matrix protein fibronectin and decreased PKG-I expression and activity via the Ras pathway. PKG-I activation with 8-bromo-cGMP, Ras inactivation with dominant negative Ras, or Ras pathway inhibition with the ERK1/2 inhibitor PD-98059 resulted in the prevention of TWEAK-induced TGF-beta1 upregulation. In vivo, exogenous administration of TWEAK to wild-type mice downregulated kidney PKG-I and increased kidney TGF-beta1 expression. These effects were blunted in H-Ras knockout mice. Together, these data demonstrate, for the first time, the key role of PKG-I in TGF-beta1 induction by TWEAK in kidney cells. |
