The role of TGF-beta1 in hydrogen peroxide-induced senescence-like morphogenesis has been described. The aim of this work was to investigate whether TGF-beta1-independent changes in protein synthesis are involved in this morphogenesis and to study possible mechanisms occurring earlier than TGF-beta1 overexpression. Among the multiple TGF-beta1-independent changes in protein neosynthesis, followed or not by posttranslational modifications, identified by proteomic analysis herein, those of ezrin, L-caldesmon, and HSP27 were particularly studied. Rho-GTPase cdc42 was shown to be responsible for p38(MAPK) activation, in turn triggering phosphorylation of L-caldesmon and HSP27. Cdc42 was also shown to be mainly responsible for the increase in TGF-beta1 mRNA level observed at 24 h after treatment with H(2)O(2) and onward. This study further clarified the mechanisms of senescence-like morphogenesis in addition to the previously demonstrated role of TGF-beta1 signaling pathways.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.freeradbiomed.2008.01.026DOI Listing

Publication Analysis

Top Keywords

tgf-beta1-independent changes
12
changes protein
12
senescence-like morphogenesis
12
protein neosynthesis
8
hydrogen peroxide-induced
8
peroxide-induced senescence-like
8
role tgf-beta1
8
l-caldesmon hsp27
8
cdc42 responsible
8
role tgf-beta1-independent
4

Similar Publications

Purpose: To evaluate the role of interleukin-4 in influencing idiopathic epiretinal membrane (iERM) formation and early progression post cataract surgery (PCS) from clinical and experimental perspectives.

Methods: We quantified levels of IL-4 in aqueous humor (AH) samples from 22 iERM patients and 31 control subjects collected before and 20 hours after cataract surgeries using ELISA. After a 3-month follow-up, the association between IL-4 levels and iERM progression measurements was identified.

View Article and Find Full Text PDF

Background: The activation of hepatic stellate cells (HSCs) plays a central role in liver fibrosis. α-ketoglutarate is a natural metabolite and previous studies have shown that increase in intracellular α-ketoglutarate can inhibit HSC activation.

Aim: The aim of the present study is to determine the changes and role of intracellular α-ketoglutarate in HSC activation and clarify its mechanism of action.

View Article and Find Full Text PDF

Upregulation of Smad7, an inhibitor of transforming growth factor-β1 (TGF-β1), occurs in sporadic colorectal cancer (CRC) and knockdown of Smad7 inhibits CRC cell growth, a phenomenon that associates with decreased expression of cell division cycle 25 homolog A and arrest of cells in the S phase of the cell cycle. These findings occur in CRC cells unresponsive to TGF-β1, thus suggesting the existence of a Smad7-mediated TGF-β1-independent mechanism that controls CRC cell behavior. Here we show that Smad7 inhibition with a specific Smad7 antisense oligonucleotide upregulates eukaryotic translation initiation factor 2α (eIF2α) phosphorylation, a transcription factor involved in the regulation of cell cycle arrest and induction of cell death, and induces activating transcription factor 4 (ATF4) and CCAAT/enhancer binding protein homology protein (CHOP), two downstream targets of eIF2α.

View Article and Find Full Text PDF

Tubular epithelial-myofibroblast transition (TEMT) is an important process in renal tubulointerstitial fibrosis. Interleukin-1α (IL-1α) and transforming growth factor-β1 (TGF-β1) have been demonstrated to be key inducers of TEMT. In mouse embryonic fibroblast cells (NIH3T3), P311 protein induces phenotypic changes that are consistent to myofibroblast transformation.

View Article and Find Full Text PDF

TNF-related weak inducer of apoptosis (TWEAK) regulates junctional proteins in tubular epithelial cells via canonical NF-κB pathway and ERK activation.

J Cell Physiol

July 2015

Laboratory of Nephrology and Vascular Pathology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.

The tubular epithelium may be intrinsically involved in promoting kidney injury by junctional instability, epithelial-mesenchymal transition (EMT) and extracellular matrix remodelling. In this work, we investigated whether the pleiotropic and proinflammatory cytokine tumor necrosis factor-like weak inducer of apoptosis (TWEAK), could be able to disturb junctional protein expression and to induce EMT of tubular cells. In cultured murine proximal tubular cells TWEAK induced phenotypic changes that were accompanied by F-actin redistribution, loss of epithelial adherent (E-cadherin, Cadherin-16, β-catenin) and tight junction (ZO-1) proteins, and re-expression of the mesenchymal protein Vimentin.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!