scholarly journals Peroxisome Proliferator-Activated Receptor-γ Activation Inhibits Tumor Metastasis by Antagonizing Smad3-Mediated Epithelial-Mesenchymal Transition

2010 ◽  
Vol 9 (12) ◽  
pp. 3221-3232 ◽  
Author(s):  
Ajaya Kumar Reka ◽  
Himabindu Kurapati ◽  
Venkata R. Narala ◽  
Guido Bommer ◽  
Jun Chen ◽  
...  
Keyword(s):  
Tumor Metastasis ◽  
Epithelial Mesenchymal Transition ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Mesenchymal Transition

scholarly journals Fenofibrate Improved Interstitial Fibrosis of Renal Allograft through Inhibited Epithelial-Mesenchymal Transition Induced by Oxidative Stress

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Yishu Wang ◽  
Lei Pang ◽  
Yanghe Zhang ◽  
Jiahui Lin ◽  
Honglan Zhou
Keyword(s):  
Oxidative Stress ◽  
Rat Model ◽  
Renal Allograft ◽  
Epithelial Mesenchymal Transition ◽  
Interstitial Fibrosis ◽  
Peroxisome Proliferator ◽  
Tubular Atrophy ◽  
Peroxisome Proliferator Activated Receptor ◽  
Mesenchymal Transition ◽  
Stage Renal Disease

The best treatment for end-stage renal disease is renal transplantation. However, it is often difficult to maintain a renal allograft healthy for a long time following transplantation. Interstitial fibrosis and tubular atrophy (IF/TA) are significant histopathologic characteristics of a compromised renal allograft. There is no effective therapy to improve renal allograft function once IF/TA sets in. Although there are many underlying factors that can induce IF/TA, the pathogenesis of IF/TA has not been fully elucidated. It has been found that epithelial-mesenchymal transition (EMT) significantly contributes to the development of IF/TA. Oxidative stress is one of the main causes that induce EMT in renal allografts. In this study, we have used H2O2 to induce oxidative stress in renal tubular epithelial cells (NRK-52e) of rats. We also pretreated NRK-52e cells with an antioxidant (N-acetyl L-cysteine (NAC)) 1 h prior to the treatment with H2O2. Furthermore, we used fenofibrate (a peroxisome proliferator-activated receptor α agonist) to treat NRK-52e cells and a renal transplant rat model. Our results reveal that oxidative stress induces EMT in NRK-52e cells, and pretreatment with NAC can suppress EMT in these cells. Moreover, fenofibrate suppresses fibrosis by ameliorating oxidative stress-induced EMT in a rat model. Thus, fenofibrate may effectively prevent the development of fibrosis in renal allograft and improve the outcome.

scholarly journals Curcumin Suppresses Intestinal Fibrosis by Inhibition of PPARγ-Mediated Epithelial-Mesenchymal Transition

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Su Xu ◽  
Bin Jiang ◽  
Hui Wang ◽  
Cunsi Shen ◽  
Hao Chen ◽  
...  
Keyword(s):  
Nuclear Translocation ◽  
Epithelial Mesenchymal Transition ◽  
Smooth Muscle Actin ◽  
Peroxisome Proliferator ◽  
Colon Tissue ◽  
Peroxisome Proliferator Activated Receptor ◽  
Smad Pathway ◽  
Mesenchymal Transition ◽  
Intestinal Fibrosis ◽  
E Cadherin

Intestinal fibrotic stricture is a major complication of Crohn’s disease (CD) and epithelial-to-mesenchymal transition (EMT) is considered as an important contributor to the formation of intestinal fibrosis by increasing extracellular matrix (ECM) proteins. Curcumin, a compound derived from rhizomes ofCurcuma, has been demonstrated with a potent antifibrotic effect. However, its effect on intestinal fibrosis and the potential mechanism is not completely understood. Here we found that curcumin pretreatment significantly represses TGF-β1-induced Smad pathway and decreases its downstreamα-smooth muscle actin (α-SMA) gene expression in intestinal epithelial cells (IEC-6); in contrast, curcumin increases expression of E-cadherin and peroxisome proliferator-activated receptorγ(PPARγ) in IEC-6. Moreover, curcumin promotes nuclear translocation of PPARγand the inhibitory effect of curcumin on EMT could be reversed by PPARγantagonist GW9662. Consistently, in the rat model of intestinal fibrosis induced by 2,4,5-trinitrobenzene sulphonic acid (TNBS), oral curcumin attenuates intestinal fibrosis by increasing the expression of PPARγand E-cadherin and decreasing the expression ofα-SMA, FN, and CTGF in colon tissue. Collectively, these results indicated that curcumin is able to prevent EMT progress in intestinal fibrosis by PPARγ-mediated repression of TGF-β1/Smad pathway.

scholarly journals PGC-1α Suppresses the Activation of TGF-β/Smad Signaling via Targeting TGFβRI Downregulation by let-7b/c Upregulation

2019 ◽  
Vol 20 (20) ◽  
pp. 5084 ◽  
Author(s):  
Hoon-In Choi ◽  
Jung Sun Park ◽  
Dong-Hyun Kim ◽  
Chang Seong Kim ◽  
Eun Hui Bae ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Epithelial Mesenchymal Transition ◽  
Kidney Diseases ◽  
Peroxisome Proliferator ◽  
Major Pathway ◽  
Peroxisome Proliferator Activated Receptor ◽  
Mesenchymal Transition ◽  
Smad Signaling ◽  
Smad Signaling Pathway ◽  
Signaling Activation

TGF-β/Smad signaling is a major pathway in progressive fibrotic processes, and further studies on the molecular mechanisms of TGF-β/Smad signaling are still needed for their therapeutic targeting. Recently, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) was shown to improve renal fibrosis, making it an attractive target for chronic kidney diseases (CKDs). Here, we show the mechanism by which PGC-1α regulates the TGF-β/Smad signaling pathway using HK-2 cell lines stably overexpressing empty vector (mock cells) or human PGC1α (PGC1α cells). Stable PGC-1α overexpression negatively regulated the expression of TGF-β-induced epithelial-mesenchymal transition (EMT) markers (fibronectin, E-cadherin, vimentin, and α-SMA) and EMT-related transcription factors (Snail and Slug) compared to mock cells, inhibiting fibrotic progression. Interestingly, among molecules upstream of Smad2/3 activation, the gene expression of only TGFβRI, but not TGFβRII, was downregulated in PGC-1α cells. In addition, the downregulation of TGFβRI by PGC-1α was associated with the upregulation of let-7b/c, miRNA for which the 3′ untranslated region (UTR) of TGFβRI contains a binding site. In conclusion, PGC-1α suppresses TGF-β/Smad signaling activation via targeting TGFβRI downregulation by let-7b/c upregulation.

scholarly journals PPAR-gamma induced AKT3 expression increases levels of mitochondrial biogenesis driving prostate cancer

Oncogene ◽  
2021 ◽  
Vol 40 (13) ◽  
pp. 2355-2366
Author(s):  
Laura C. A. Galbraith ◽  
Ernest Mui ◽  
Colin Nixon ◽  
Ann Hedley ◽  
David Strachan ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Mitochondrial Biogenesis ◽  
Nuclear Export ◽  
Epithelial To Mesenchymal Transition ◽  
Ppar Gamma ◽  
Peroxisome Proliferator ◽  
Serine Threonine Kinase ◽  
Peroxisome Proliferator Activated Receptor ◽  
Mesenchymal Transition ◽  
And Function

AbstractPeroxisome Proliferator-Activated Receptor Gamma (PPARG) is one of the three members of the PPAR family of transcription factors. Besides its roles in adipocyte differentiation and lipid metabolism, we recently demonstrated an association between PPARG and metastasis in prostate cancer. In this study a functional effect of PPARG on AKT serine/threonine kinase 3 (AKT3), which ultimately results in a more aggressive disease phenotype was identified. AKT3 has previously been shown to regulate PPARG co-activator 1 alpha (PGC1α) localisation and function through its action on chromosome maintenance region 1 (CRM1). AKT3 promotes PGC1α localisation to the nucleus through its inhibitory effects on CRM1, a known nuclear export protein. Collectively our results demonstrate how PPARG over-expression drives an increase in AKT3 levels, which in turn has the downstream effect of increasing PGC1α localisation within the nucleus, driving mitochondrial biogenesis. Furthermore, this increase in mitochondrial mass provides higher energetic output in the form of elevated ATP levels which may fuel the progression of the tumour cell through epithelial to mesenchymal transition (EMT) and ultimately metastasis.

scholarly journals Phosphorylation of Serine 11 and Serine 92 as New Positive Regulators of Human Snail1 Function: Potential Involvement of Casein Kinase-2 and the cAMP-activated Kinase Protein Kinase A

2010 ◽  
Vol 21 (2) ◽  
pp. 244-253 ◽  
Author(s):  
Matthew Reid MacPherson ◽  
Patricia Molina ◽  
Serhiy Souchelnytskyi ◽  
Christer Wernstedt ◽  
Jorge Martin-Pérez ◽  
...  
Keyword(s):  
Nuclear Export ◽  
Tumor Metastasis ◽  
Epithelial Mesenchymal Transition ◽  
Cop9 Signalosome ◽  
Mesenchymal Transition ◽  
Depth Analysis ◽  
Positive Regulators

Snail1 is a major factor for epithelial-mesenchymal transition (EMT), an important event in tumor metastasis and in other pathologies. Snail1 is tightly regulated at transcriptional and posttranscriptional levels. Control of Snail1 protein stability and nuclear export by GSK3β phosphorylation is important for Snail1 functionality. Stabilization mechanisms independent of GSK3β have also been reported, including interaction with LOXL2 or regulation of the COP9 signalosome by inflammatory signals. To get further insights into the role of Snail1 phosphorylation, we have performed an in-depth analysis of in vivo human Snail1 phosphorylation combined with mutational studies. We identify new phosphorylation sites at serines 11, 82, and 92 and confirmed previously suggested phosphorylations at serine 104 and 107. Serines 11 and 92 participate in the control of Snail1 stability and positively regulate Snail1 repressive function and its interaction with mSin3A corepressor. Furthermore, serines 11 and 92 are required for Snail1-mediated EMT and cell viability, respectively. PKA and CK2 have been characterized as the main kinases responsible for in vitro Snail1 phosphorylation at serine 11 and 92, respectively. These results highlight serines 11 and 92 as new players in Snail1 regulation and suggest the participation of CK2 and PKA in the modulation of Snail1 functionality.

Sign in / Sign up

Export Citation Format

Share Document