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Fu-Qiang Wen

Publications and source records attributed to Fu-Qiang Wen.

At least 19 recordsLinked to original sources
PubMed2006

Transforming growth factor-beta receptor type 1 (TGFbetaRI) kinase activity but not p38 activation is required for TGFbetaRI-induced myofibroblast differentiation and profibrotic gene expression.

Transforming growth factor-beta (TGFbeta) is a major mediator of normal wound healing and of pathological conditions involving fibrosis, such as idiopathic pulmonary fibrosis. TGFbeta also stimulates the differentiation of myofibroblasts, a hallmark of fibrotic diseases. In this study, we examined the underlying processes of TGFbetaRI kinase activity in myofibroblast conversion of human lung fibroblasts using specific inhibitors of TGFbetaRI (SD-208) and p38 mitogen-activated kinase (SD-282). We demonstrated that SD-208, but not SD-282, inhibited TGFbeta-induced SMAD signaling, myofibroblast transformation, and collagen gel contraction. Furthermore, we extended our findings to a rat bleomycin-induced lung fibrosis model, demonstrating a significant decrease in the number of myofibroblasts at fibroblastic foci in animals treated with SD-208 but not those treated with SD-282. SD-208 also reduced collagen deposition in this in vivo model. Microarray analysis of human lung fibroblasts identified molecular fingerprints of these processes and showed that SD-208 had global effects on reversing TGFbeta-induced genes involved in fibrosis, inflammation, cell proliferation, cytoskeletal organization, and apoptosis. These studies also revealed that although the p38 pathway may not be needed for appearance or disappearance of the myofibroblast, it can mediate a subset of inflammatory and fibrogenic events of the myofibroblast during the process of tissue repair and fibrosis. Our findings suggest that inhibitors such as SD-208 may be therapeutically useful in human interstitial lung diseases and pulmonary fibrosis.

Activin Receptors, Type I↗
PubMed2005

TGF-beta1 and serum both stimulate contraction but differentially affect apoptosis in 3D collagen gels.

Apoptosis of fibroblasts may be key for the removal of cells following repair processes. Contraction of three-dimensional collagen gels is a model of wound healing and remodeling. Here two potent inducers of contraction, TGF-beta1 and fetal calf serum (FCS) were evaluated for their effect on fibroblast apoptosis in contracting collagen gels. Human fetal lung fibroblasts were cultured in floating type I collagen gels, exposed to TGF-beta1 or FCS, and allowed to contract for 5 days. Apoptosis was evaluated using TUNEL and confirmed by DNA content profiling. Both TGF-beta1 and serum significantly augmented collagen gel contraction. TGF-beta1 also increased apoptosis assessed by TUNEL positivity and DNA content analysis. In contrast, serum did not affect apoptosis. TGF-beta1 induction of apoptosis was associated with augmented expression of Bax, a pro-apoptotic member of the Bax/Bcl-2 family, inhibition of Bcl-2, an anti-apoptotic member of the same family, and inhibition of both cIAP-1 and XIAP, two inhibitors of the caspase cascade. Serum was associated with an increase in cIAP-1 and Bcl-2, anti-apoptotic proteins. Interestingly, serum was also associated with an apparent increase in Bax, a pro-apoptotic protein. Blockade of Smad3 with either siRNA or by using murine fibroblasts deficient in Smad3 resulted in a lack of TGF-beta induction of augmented contraction and apoptosis. Contraction induced by different factors, therefore, may be differentially associated with apoptosis, which may be related to the persistence or resolution of the fibroblasts that accumulate following injury.

Apoptosis↗
PubMed2005

Smad3 mediates TGF-beta1-induced collagen gel contraction by human lung fibroblasts.

Transforming growth factor-beta1 (TGF-beta1) is a key mediator in tissue repair and fibrosis. Using small interference RNA (siRNA), the role of Smad2 and Smad3 in TGF-beta stimulation of human lung fibroblast contraction of collagenous matrix and induction of alpha-SMA and the role of alpha-SMA in contraction were assessed. HFL-1 cells were transfected with Smad2, Smad3 or control-siRNA, and cultured in floating Type I collagen gels +/- -TGF-beta1. TGF-beta1 augmented gel contraction in Smad2-siRNA- and control-siRNA-treated cells, but had no effect in Smad3-siRNA-treated cells. Similarly, TGF-beta1 upregulated alpha-SMA in Smad2-siRNA- and control-siRNA-treated cells, but had no effect on Smad3-siRNA-treated cells. Alpha-SMA-siRNA-treated cells did not contact the collagen gels with or without TGF-beta1, suggesting alpha-SMA is required for gel contraction. Thus, Smad3 mediates TGF-beta1-induced contraction and alpha-SMA induction in human lung fibroblasts. Smad3, therefore, could be a target for blocking contraction of human fibrotic tissue induced by TGF-beta1.

Actins↗
PubMed2005

Smad3 mediates TGF-beta1 induction of VEGF production in lung fibroblasts.

Transforming growth factor-beta1 (TGF-beta1) is a key factor in a variety of physiological and pathological processes. Vascular endothelial growth factor (VEGF) is a key angiogenic factor, and vascular change is one of the features of airway remodeling. We examined the effect of TGF-beta1 on VEGF production by fibroblasts from mice lacking expression of Smad2 or Smad3 as well as human lung fibroblasts treated with or without Smad2 or Smad3 siRNA. TGF-beta1 stimulated VEGF production by fibroblasts from Smad2 deficient animals and wildtype animals. In contrast, TGF-beta1 did not affect VEGF production by fibroblasts from Samd3 deficient mice. Similarly, TGF-beta1 failed to stimulate VEGF production by HFL-1 cells treated with Samd3 siRNA but significantly increased VEGF production by the cells treated with Smad2 siRNA. These result suggest that TGF-beta1 stimulation of VEGF production by fibroblasts is regulated by Smad3 but not by Smad2 signaling.

Animals↗
PubMed2005

[Progress in study of ADAM33 gene].

A disintegin and metalloprotease-encoding gene (ADAM) 33, located on the short arm of chromosome 20 (20p13), was recently identified through a genome-wide scan for asthma. It is a new member of a family of genes encoding a group of the metalloproteinase superfamily called the ADAM family. The proteolytic activity of the ADAMs plays important role in the healthy and disease states. The identification of ADAM33 as a candidate gene for asthma may provide a newly therapeutic target for this disease.

ADAM Proteins↗
PubMed2004

Reversible cigarette smoke extract-induced DNA damage in human lung fibroblasts.

Cigarette smoke contains thousands of chemicals, many of which may contribute to cytotoxicity and carcinogenesis. Using assays detecting DNA strand breaks (terminal transferase dUTP nick end labeling [TUNEL]) and DNA content (flow cytometry), we evaluated the genotoxic effect of cigarette smoke extract (CSE) on human fetal lung fibroblasts (HFL-1) cultured in three-dimensional collagen gels as well as in monolayer culture. When HFL-1 cells were exposed to CSE, DNA strand breaks were detected in most, as determined by TUNEL. This effect was dependent on CSE concentration, duration of CSE exposure, and the density of HFL-1 cells cast into the collagen gels. Buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis, significantly increased DNA damage induced by 1% CSE, and N-acetylcysteine, a glutathione precursor, blocked 5% CSE from inducing DNA damage. After CSE exposure, most cells were TUNEL-positive, but DNA quantification revealed no hypodiploid cells, indicating that apoptosis was not occurring during the CSE exposure. CSE-induced DNA damage was reversible, and cells proliferated when CSE was removed after 24 h exposure. These results demonstrate that cigarette smoke can induce DNA damage in HFL-1 cells cultured in both three-dimensional collagen gels and monolayer cultures, and that oxidants likely play a role in this damage. Moreover, this DNA damage is reversible, with cells surviving and TUNEL positivity reversing when CSE is removed within 24 h.

Acetylcysteine↗
PubMed2004

Interferon-gamma inhibits transforming growth factor-beta production in human airway epithelial cells by targeting Smads.

Because interferon (IFN)-gamma may attenuate pulmonary fibrosis, we hypothesized that IFN-gamma may regulate transforming growth factor (TGF)-beta production by airway epithelial cells. Human bronchial epithelial cells (HBECs) were incubated with IFN-gamma +/- TGF-beta1, -beta3, or interleukin (IL)-1beta, platelet-derived growth factor (PDGF), epidermal growth factor, and IL-4. TGF-beta2 protein was measured by enzyme-linked immunosorbent assay and mRNA expression for TGF-beta2, Smad 2, 3, 4, and 7 was evaluated by real-time reverse transcriptase-polymerase chain reaction. Localization of Smads 2, 3, 4, and 7 was evaluated by immunostaining. Exogenous TGF-beta1 and 3, IL-1beta, PDGF, and IL-4 enhanced TGF-beta2 release by HBECs (P < 0.01). IFN-gamma reduced basal and TGF-beta or IL-4-augmented TGF-beta2 release, but had little effect on IL-1beta- or PDGF-augmented TGF-beta2 release. IFN-gamma stimulated Smad 7 protein and mRNA expression. Smad 7-specific siRNA decreased Smad 7 protein expression both in control and IFN-gamma-treated cells. The inhibitory effect of IFN-gamma on TGF-beta2 production was abrogated when the HBECs were treated with Smad 7 siRNA. These results suggest that IFN-gamma down regulates TGF-beta2 production by HBECs by regulating Smad 7. Through this mechanism, IFN-gamma may play an important role in tissue remodeling.

Cells, Cultured↗
PubMed2004

Cytokines modulate cilomilast response in lung fibroblasts.

Fibroblasts, as a major source of extracellular interstitial connective tissue matrix, play an important role in wound healing and the development of fibrosis. The phosphodiesterase (PDE) 4 inhibitor cilomilast inhibits fibroblast chemotaxis and fibroblast-mediated gel contraction. Using the Boyden blindwell chamber chemotaxis assay and the type I collagen gel contraction model, this study investigated whether specific cytokines modulate cilomilast's inhibitory effect through regulation of endogenous PGE(2) production. Human recombinant IL-1beta stimulated PGE(2) production and shifted the cilomilast concentration-dependence curve to the left in both assay systems, indicating increased sensitivity to cilomilast. In contrast, human recombinant IL-4 inhibited PGE(2) production and shifted the cilomilast concentration-dependence curve to the right in both systems. In summary, the inhibitory effect of cilomilast on fibroblast migration and collagen gel contraction is modulated by IL-1beta and IL-4 through regulation of PGE(2) production.

Bronchodilator Agents↗
PubMed2004

IL-4 and IL-13 induce chemotaxis of human foreskin fibroblasts, but not human fetal lung fibroblasts.

Through shared receptors, IL-4 and IL-13 have been suggested to regulate not only inflammatory cells, but also to play a role in stimulating fibroblasts during fibrotic processes. Previous studies have shown that IL-4 is a chemoattractant for foreskin fibroblasts. The current study was designed to determine the effect of IL-4 and IL-13 on the migration of two types of fibroblasts: foreskin and human fetal lung fibroblasts (HFL-1). Using the Boyden blindwell chamber method, human foreskin or fetal lung fibroblasts (both 10(6)/mL) were placed in upper wells with various concentrations of IL-4 or IL-13 in the lower wells as chemoattractants. Both IL-4 (1 pg/mL) and IL-13 (100 pg/mL) induced foreskin fibroblast chemotaxis, up to 50 +/- 8 and 24 +/- 7 cells/5 high-power fields, respectively (both p < 0.05). In contrast, neither cytokine induced migration of the lung fibroblasts although both type of cells express IL-4 receptor and IL-13alpha1 receptor. These results suggest that fibroblasts are heterogeneous with regard to their ability to respond to cytokine-driven chemotaxis. Therefore, the role of specific cytokines in mediating fibrotic responses might vary depending on local mesenchymal cell responses.

Cell Movement↗
PubMed2004

Cigarette smoke stimulates MMP-1 production by human lung fibroblasts through the ERK1/2 pathway.

An imbalance between proteases and anti-proteases is believed to play an important role in the pathogenesis of emphysema. In this study, we explored the hypothesis that cigarette smoke can alter tissue structure through an effect on the release of matrix metalloproteinase-1 (MMP-1) and type I tissue inhibitor of metalloproteinases (TIMP-1). Cigarette smoke extract (CSE) significantly stimulated pro-MMP-1 production (determined by ELISA and immunoblots) and mRNA expression (by real-time RT-PCR) by human fetal lung fibroblasts (HFL-1) in a concentration-dependent manner (2.5-10%). High concentrations of CSE (10%) could potentially activate the latent form of MMP-1 as the high molecular weight (52 kDa) form was converted into a low molecular weight (42 kDa) form consistent with active MMP-1. TIMP-1 production, however, was not significantly altered by the concentrations of CSE tested. After 30 min exposure, CSE significantly induced ERK1/2 phosphorylation, which then gradually decreased from 90 minutes to 3 hours. PD98059, a specific inhibitor of ERK-MAPK, significantly blocked the CSE effect on ERK1/2 phosphorylation. Furthermore, PD98059 significantly inhibited the CSE effect on MMP-1 production and mRNA expression by fibroblasts. These results suggest that cigarette smoke stimulates production and likely activates MMP-1 through activating ERK1/2 signal transduction pathway. By inducing MMP-1, cigarette smoke may result in excess tissue destruction and contribute to the development of emphysema.

Calcium-Calmodulin-Dependent Protein Kinases↗
PubMed2003

Smad3 mediates the TGF-beta-induced contraction of type I collagen gels by mouse embryo fibroblasts.

TGF-beta signals through TGF-beta receptors and Smad proteins. TGF-beta also augments fibroblast-mediated collagen gel contraction, an in vitro model of connective tissue remodeling. To investigate the importance of Smad2 or Smad3 in this augmentation process, embryo-derived fibroblasts from mice lacking expression of Smad2 or Smad3 genes were cast into native type I collagen gels. Fibroblast-populated gels were then released into 0.2% FCS-DMEM alone or with recombinant human TGF-beta1, beta2, beta3, or recombinant rat PDGF-BB. Gel contraction was determined using an image analyzer. All three isoforms of TGF-beta significantly augmented contraction of collagen gels mediated by fibroblasts with genotypes of Smad2 knockout (S2KO), Smad2 wildtype (S2WT), and Smad3 wildtype (S3WT), but not Smad3 knockout (S3KO) mice. PDGF-BB augmented collagen gel contraction by all fibroblast types. These results suggest that expression of Smad3 but not Smad2 may be critical in TGF-beta augmentation of fibroblast-mediated collagen gel contraction. Thus, the Smad3 gene could be a target for blocking contraction of fibrotic tissue induced by TGF-beta.

Animals↗
PubMed2003

Glucocorticoids modulate TGF-beta production by human fetal lung fibroblasts.

TGF-beta1 is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGF-beta isoforms affect TGF-beta production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFLF) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TGF-beta1, -beta2, or -beta3. Post-culture media were collected for ELISA assays of TGF-beta1, -beta2, and -beta3. TGF-beta mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TFG-beta2 and -beta3 stimulated TGF-beta1 production significantly (p < 0.01 relative to control). TGF-beta1 stimulated TGF-beta2 production (p < 0.01 relative to control). TGF-beta3 was undetectable. Glucocorticoids significantly inhibited TGF-beta1 and TGF-beta2 production and reduced expression of the up-regulated TGF-beta1 and TGF-beta2 mRNA induced by exogenous TGF-beta1, -beta2, or -beta3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF-beta-stimulated cells, it was reduced by glucocorticoids. Thus, TGF-beta isoforms may stimulate production of various TGF-beta isoforms in the lung. Glucocorticoids then may block TGF-beta production by modulating mRNA levels and c-Jun.

Cells, Cultured↗
PubMed2003

TH2 Cytokine-enhanced and TGF-beta-enhanced vascular endothelial growth factor production by cultured human airway smooth muscle cells is attenuated by IFN-gamma and corticosteroids.

BACKGROUND: T(H)2 and T(H)1 cytokines have opposite effects on many aspects of the inflammatory response. METHODS: This study was designed to determine if cytokines possibly present in asthma can modulate airway smooth muscle cell (ASMC) production of vascular endothelial growth factor (VEGF) and thus contribute to altered airway vascularity. ASMC were incubated for 24 hours with various concentrations of T(H)2 cytokines (IL-4, IL-5, IL-10, and IL-13); transforming growth factor (TGF)-beta1, TGF-beta2, or TGF-beta3; and IL-1beta or TNF-alpha with or without IFN-gamma. Budesonide and exogenous prostaglandin (PG)E(2) were also evaluated. Postculture media were assayed for VEGF and PGE(2) by ELISA. RESULTS: IL-4, IL-5, and IL-13 alone but not IL-10 enhanced VEGF production by ASMC in a concentration-dependent manner. IFN-gamma alone inhibited spontaneous VEGF release by ASMC and concentration-dependently attenuated IL-4-augmented, IL-5-augmented, or IL-13-augmented production of VEGF (P <.01). All three TGF-beta isoforms augmented VEGF production, which was reduced by IFN-gamma (P <.005). IL-1beta also increased VEGF production, but this was not affected by IFN-gamma (P >.05). TNF-alpha alone had little effect on VEGF release by ASMC. Production of VEGF stimulated by all cytokines was inhibited by budesonide. Exogenous PGE(2) increased VEGF release, but cytokine modulation of PGE(2) release did not always correlate with VEGF release. CONCLUSIONS: T(H)2 cytokines and TGF-beta stimulate ASMC release of VEGF. This can be inhibited by IFN-gamma and glucocorticoids.

Anti-Inflammatory Agents↗
PubMed2003

Ultrafine carbon black particles inhibit human lung fibroblast-mediated collagen gel contraction.

Both acute and chronic exposure to particulates have been associated with increased mortality and morbidity from a number of causes, including chronic obstructive pulmonary disease and other chronic lung diseases. The current study evaluated the hypothesis that ultrafine carbon particles, a component of ambient particulates, could affect tissue repair. To assess this, the three-dimensional collagen gel contraction model was used. Ultrafine carbon black particles, but not fine carbon black, inhibited fibroblast-mediated collagen gel contraction. Although previous research has indicated that inflammatory effects of ultrafine carbon black particles are mediated by oxidant mechanisms, the current study suggests that ultrafine carbon black's inhibition of fibroblast gel contraction is mediated by the binding of both fibronectin and transforming growth factor (TGF)-beta to the ultrafine particles. Binding of TGF-beta was associated with a reduction in nuclear localization of Smads, indicative of inhibition of TGF-beta signal transduction. There was also a decrease in fibronectin mRNA, consistent with a decrease in TGF-beta-mediated response. Taken together, these results demonstrate the ability of ultrafine particles to contribute to altered tissue repair and extend the known mechanisms by which these biologically active particles exert their effects.

Base Sequence↗
PubMed2002

Effect of cigarette smoke on fibroblast-mediated gel contraction is dependent on cell density.

Cigarette smoke exposure has been associated with a variety of diseases, including emphysema. The current study evaluated the interaction of cell density and cigarette smoke extract (CSE) on fibroblast contraction of collagen gels. Protein levels of transforming growth factor (TGF)-beta1, fibronectin, PGE(2), and TGF-beta1 mRNA were quantified. Although both 5 and 10% CSE inhibited contraction by low-density fibroblasts (1 x 10(5) cell/ml), only 5% CSE augmented contraction in higher-density cultures (3-5 x 10(5) cells/ml). CSE also inhibited fibronectin and TGF-beta1 production in low-density cultures but stimulated fibronectin production in high-density cultures. Active TGF-beta1 was readily detectable only in higher-density cultures and was markedly augmented by 5% CSE. In contrast, although TGF-beta1 mRNA expression was inhibited in high-density cultures by 10% CSE, expression was increased in the presence of 5% CSE. These results suggest that CSE-induced inhibition of low-density fibroblast contraction is due to inhibition of fibronectin production, whereas CSE's stimulatory effect on high-density cells is the result of increased release of TGF-beta1. These effects may help explain the varied pathologies associated with exposure to cigarette smoke.

Antibodies↗
PubMed2002

Glucocorticoids modulate TGF-beta production.

TGF-beta is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB-beta isoforms affect TGF-beta production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-beta1, -beta2, and -beta3. TGF-beta mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-beta2 and -beta3 stimulated TGF-beta1 production significantly (p < 0.01 relative to control). TGF-beta1 stimulated TGF-beta2 production (p < 0.01 relative to control). TGF-beta3 was undetectable. Glucocorticoids significantly inhibited TGF-beta1 and -beta2 production and reduced expression of the upregulated TGF-beta1 and -beta2 mRNA induced by exogenous TGF-beta1, -beta2 or -beta3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF-beta-stimulated cells, it was reduced by glucocorticoids. Thus, TGF-beta isoforms may stimulate production of various TGF-beta isoforms in the lung. Glucocorticoids then may block TGF-beta production by modulating mRNA levels and c-Jun.

Animals↗