Article

Low-dose paclitaxel ameliorates renal fibrosis in rat UUO model by inhibition of TGF-beta/Smad activity.

Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, PR China.
Laboratory Investigation (Impact Factor: 3.96). 02/2010; 90(3):436-47. DOI: 10.1038/labinvest.2009.149
Source: PubMed

ABSTRACT Transforming growth factor-beta (TGF-beta) has a pivotal function in the progression of renal fibrosis in a wide variety of renal diseases. Smad proteins have been identified to have an important function in regulating the expression of extracellular matrix (ECM) proteins through TGF-beta signaling pathway. Aberrant TGF-beta/Smad signaling can be modulated by stabilization of microtubules with paclitaxel. In this study, we investigated if paclitaxel can attenuate tubulointerstitial fibrosis in a rat model of unilateral ureteral obstruction (UUO). Rats in groups of six were subjected to UUO and received low-dose intraperitoneal injection of paclitaxel (0.3 mg/kg) twice a week. They were killed at day 7 and 14 after UUO or Sham operation. TGF-beta signaling cascade and status of various ECM proteins were evaluated by RT-PCR, western blotting and immunohistochemical or immunofluorescence staining. The paclitaxel treatment markedly suppressed Smad2 and Smad3 phosphorylation. This was associated with attenuated expression of integrin-linked kinase, collagens I and III, fibronectin (FN) and alpha-smooth muscle actin, and a substantial decrease in renal fibrosis in animals that underwent UUO and received paclitaxel. These data indicate that the low-dose paclitaxel ameliorates renal tubulointerstitial fibrosis by modulating TGF-beta signaling, and thus, the paclitaxel may have some therapeutic value in humans.

0 Bookmarks
 · 
118 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Epithelial-to-mesenchymal transition (EMT) induced by TGF-ß1 is one of well-recognized factors contributing to renal fibrosis. However, the underlying molecular mechanisms of EMT are not fully understood. Brachyury, an evolutionarily conserved transcription factor, was recently identified as an important factor promoting EMT in human carcinoma cell lines. There is no evidence that Brachyury is involved in renal tubular EMT.ResultsOur results demonstrated that Brachyury was prominently induced in TGF-ß1-treated human proximal tubular epithelial (HK-2) cells and that this induction was accompanied by changes characteristic of EMT. Blockage of Brachyury expression by short interfering RNA (siRNA) in HK-2 cells effectively reversed the TGF-ß1-induced EMT phenotype. Brachyury induction repressed E-cadherin transcription; the E-cadherin promoter contains a Brachyury binding site, and decreased expression of E-cadherin occurred in Brachyury-overexpressing cells when they were transfected with reporter constructs using the promoter. This effect was partially mediated by Slug and Snail, as knockdown of Snail and Slug by siRNA effectively reversed Brachyury-mediated EMT and partially restored E¿cadherin expression. The expression of Brachyury also presented in a rat model of obstructive nephropathy and in tubulointerstitial fibrosis tissues of IgA nephropathy, suggesting that it may have a role in EMT and renal fibrosis in vivo.Conclusion Our results demonstrate for the first time that Brachyury plays an important role in regulating TGF-ß1¿mediated renal EMT and could be an attractive target for progression of renal disease therapies.
    Cell Communication and Signaling 11/2014; 12(1):76. · 4.67 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Urethral stricture, a frequent source of lower urinary tract disorders in men, is still a difficult problem for urologists. Based the anti-restenosis effect of paclitaxel on coronary artery, the role of docetaxel, a semi-synthetic analogue of paclitaxel, in limiting urethral stricture formation was studied.
    PLoS ONE 11/2014; 9(11):e112097. · 3.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: La esclerodermia es una enfermedad caracterizada por la acumulación excesiva de tejido fibroso que lleva a alteración en la estructura y función de la piel y de órganos internos. La principal citoquina involucrada en este proceso es el factor transformante de crecimiento beta y sus funciones se realizan principalmente a través de la señalización intracelular mediada por las proteínas Smad. Se han desarrollado estrategias para bloquear los efectos del factor transformante de crecimiento beta y la identificación de la vía de transmisión de señales proporciona nuevas herramientas para la investigación de futuras terapias, pero son necesarios más estudios en modelos animales y en humanos que logren reproducir en forma satisfactoria y segura los resultados.
    Revista Colombiana de Reumatología. 10/2011; 18(4):285-294.

Preview

Download
1 Download
Available from