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Collagen Production (collagen + production)
Selected AbstractsAttenuation of Bleomycin-Induced Lung Fibrosis by Oxymatrine Is Associated with Regulation of Fibroblast Proliferation and Collagen Production in Primary CultureBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 3 2008Xiaohong Chen Oxymatrine is an alkaloid extracted from the Chinese herb Sophora japonica (Sophora flavescens Ait.) with capacities of anti-inflammation, inhibition of immune reaction, antivirus, protection against acute lung injury and antihepatic fibrosis. In this study, the effect of oxymatrine on pulmonary fibrosis was investigated using a bleomycin-induced pulmonary fibrosis mouse model. The results showed that bleomycin challenge provoked severe pulmonary fibrosis with marked increase in hydroxyproline content of lung tissue and lung fibrosis fraction, which was prevented by oxymatrine in a dose-dependent manner. In addition, bleomycin injection resulted in a marked increase of myeloperoxidase activity and malondialdehyde level that was attenuated by oxymatrine. Administration of oxymatrine inhibited the proliferation of murine lung fibroblasts, arrested the cells at G0/G1 phase and reduced the expression of cell cycle regulatory protein, cyclin D1 in vitro. Furthermore, the steady-state production of collagen and the expression of ,1(I) pro-collagen and ,2(I) pro-collagen mRNA in fibroblasts were inhibited by oxymatrine in a dose-dependent manner. These results suggested that oxymatrine may attenuate pulmonary fibrosis induced by bleomycin in mice, partly through inhibition of inflammatory response and lipid peroxidation in lung induced by bleomycin and reduction of fibroblast proliferation and collagen synthesis. [source] The characterization and optimization of injectable silicone resin particles in conjunction with dermal fibroblasts and growth factors: An in vitro studyJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2010Robert M. Crews Abstract Minimally invasive subdermal injection of liquid silicone has been used clinically to augment the soft tissue of the foot to mitigate high pressures that cause diabetic foot ulcers. However, implant migration has been a clinical issue. The objective of this study was to assess the effects of three specific concentrations of silicone resin particles (12 ,m average diameter) in conjunction with either platelet-derived growth factor (PDGF-BB) or basic fibroblast growth factor (bFGF) on fibroblast cell proliferation, collagen synthesis, cell morphology, and migration through in vitro assays and a monolayer scratch wound model. PDGF and bFGF enhanced the proliferation of fibroblasts 5.7-fold and fivefold, respectively, while the addition of silicone particles had no significant effect on proliferation. Collagen production was increased approximately twofold with the addition of bFGF and the medium concentration of particles over bFGF without particles and the PDGF groups. The addition of silicone particles had no significant effect on collagen production compared with control groups without particles. Fibroblast migration was enhanced by the addition of both PDGF and bFGF compared to controls, although slower scratch wound closure rates were observed in the presence of particles compared to controls without particles. Cell morphology suggested that particles induced cellular aggregation encircling silicone particles postwounding as well as migration into the wound area. These results suggest that silicone particles in combination with a growth factor might enhance fibroblast aggregation and implant stability, and could promote connective tissue ingrowth and implant encapsulation in the soft tissue of the diabetic foot. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010 [source] Adenosine A2A receptors in diffuse dermal fibrosis: Pathogenic role in human dermal fibroblasts and in a murine model of sclerodermaARTHRITIS & RHEUMATISM, Issue 8 2006E. S. L. Chan Objective Adenosine regulates inflammation and tissue repair, and adenosine A2A receptors promote wound healing by stimulating collagen matrix production. We therefore examined whether adenosine A2A receptors contribute to the pathogenesis of dermal fibrosis. Methods Collagen production by primary human dermal fibroblasts was analyzed by real-time polymerase chain reaction, 14C-proline incorporation, and Sircol assay. Intracellular signaling for dermal collagen production was investigated using inhibitors of MEK-1 and by demonstration of ERK phosphorylation. In vivo effects were studied in a bleomycin-induced dermal fibrosis model using adenosine A2A receptor,deficient wild-type littermate mice, C57BL/6 mice, and mice treated with adenosine A2A receptor antagonist. Morphometric features and levels of hydroxyproline were determined as measures of dermal fibrosis. Results Adenosine A2A receptor occupancy promoted collagen production by primary human dermal fibroblasts, which was blocked by adenosine A2A, but not A1 or A2B, receptor antagonism. Adenosine A2A receptor ligation stimulated ERK phosphorylation, and A2A receptor,mediated collagen production by dermal fibroblasts was blocked by MEK-1 inhibitors. Adenosine A2A receptor,deficient and A2A receptor antagonist,treated mice were protected from developing bleomycin-induced dermal fibrosis. Conclusion These results demonstrate that adenosine A2A receptors play an active role in the pathogenesis of dermal fibrosis and suggest a novel therapeutic target in the treatment and prevention of dermal fibrosis in diseases such as scleroderma. [source] Keloid-derived fibroblasts show increased secretion of factors involved in collagen turnover and depend on matrix metalloproteinase for migrationBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2005M. Fujiwara Summary Background, ,A keloid is a specific skin lesion that expands beyond the boundaries of the original injury as it heals. Histologically, it is characterized by the excessive accumulation of collagen. However, the reasons for the expansion and the invasive nature of keloids remain unknown. Objectives, We evaluated collagen degradation and migration by cultured keloid fibroblasts based on the assumption that these variables were of functional relevance to the expanding and invasive nature of keloid lesions. Methods, Collagen production was investigated by the detection of type 1 collagen (procollagen type 1C peptide: P1P). Matrix metalloproteinase (MMP)-1 (interstitial collagenase) and MMP-2 (gelatinase-A), were investigated as elements of the collagen degradation system. Enzyme immunoassays were performed to measure the production of P1P, MMP-1, MMP-2, and tissue inhibitor of metalloproteinase (TIMP)-1. To assess the production of MMP-2 its gelatinolytic activity was measured by zymography using gelatin-containing gels. The participation of transforming growth factor-,1 (TGF-,1) in the production and degradation of collagen was also investigated. Finally, the migratory activity of keloid fibroblasts was evaluated using a colony dispersion assay. Results, The production of type 1 collagen, MMP-1, MMP-2, and TIMP-1 by keloid fibroblasts was 3-fold, 6-fold, 2·4-fold, and 2-fold greater than that of normal dermal fibroblasts, respectively. Production of P1P was increased when TGF-,1 was added to cultures of keloid fibroblasts, while it was decreased when anti-TGF-,1 antibody was added to the cultures. In contrast, the production of MMP-1 was decreased by the addition of TGF-,1 to cultured keloid fibroblasts, while it was increased when anti-TGF-,1 antibody was added to the cultures. The production of MMP-2 increased after treatment with TGF-,1, but did not change significantly when anti-TGF-,1 antibody was added to the cultures. Production of TIMP-1 did not change significantly when either TGF-,1 or anti-TGF-,1 antibody was added to the cultures. Keloid fibroblasts showed a 2·5-fold increase of migratory activity compared with normal dermal fibroblasts, while the migratory activity of these fibroblasts was reduced to the control level by treatment with a broad-spectrum MMP inhibitor (GM 6001). Conclusions, Cultured keloid fibroblasts showed increased production of collagen and MMPs, and TGF-,1 played a role in this regulation of production. In addition, increased production of MMPs had a role in the high migratory activity of cultured keloid fibroblasts. [source] Vitamin C attenuates ERK signalling to inhibit the regulation of collagen production by LL-37 in human dermal fibroblastsEXPERIMENTAL DERMATOLOGY, Issue 8 2010Hyun Jeong Park Please cite this paper as: Vitamin C attenuates ERK signalling to inhibit the regulation of collagen production by LL-37 in human dermal fibroblasts. Experimental Dermatology 2010; 19: e258,e264. Abstract:, Vitamin C is used as an anti-ageing agent because of its collagen enhancing effects. The precise cellular signalling mechanism of vitamin C is not well known. Here, we investigate the profibrotic mechanism of vitamin C against LL-37. Antimicrobial peptide LL-37 decreases collagen expression at mRNA and protein levels in human dermal fibroblasts (HDFs). The ability of LL-37 to inhibit collagen expression is dependent on phosphorylation of extracellular signal-regulated kinase (ERK). HDFs and human keloid fibroblasts were treated with vitamin C followed by 2 h of LL-37 treatment. Collagen mRNA expression and total soluble collagen production inhibited by LL-37 was enhanced by treatment with 0.5 mm vitamin C. Vitamin C also decreased intracellular reactive oxygen intermediates (ROI) levels that were increased by LL-37. Furthermore, the phosphorylation of ERK was analysed by Western blot following treatment with vitamin C and LL-37. Vitamin C turned off phosphorylation of ERK that was induced by LL-37. Ets-1 transcriptional factor, which is involved in the regulation of collagen expression by LL-37, was also inhibited by vitamin C. This study shows that vitamin C enhances collagen production by inhibiting the ERK pathway induced by LL-37. [source] The molecular chaperone HSP47 rapidly senses gravitational changes in myoblastsGENES TO CELLS, Issue 11 2006Asami Oguro Skeletal muscle unloading induced by spaceflight or bed rest leads to muscle atrophy. It is unclear how muscle atrophy is caused and how muscles respond to microgravity. We addressed the response of collagen and its chaperone system to gravitational forces. We show here that expression of HSP47, a collagen-specific molecular chaperone, responds to gravitational changes, including microgravity and hypergravity in vitro and in vivo. By using the method hindlimb suspension of rats, which mimics microgravity conditions, we demonstrated that the expression of Hsp47 mRNA decreased within 1 day and the mRNA levels of collagen types I and IV were subsequently reduced. In contrast, hypergravity stimulated HSP47 expression. HSP47 and collagen types I and IV were localized intracellularly in the endoplasmic reticulum and/or Golgi apparatus of myoblasts, as expected. Intriguingly, Hsp47 mRNA levels in cultured myoblasts increased significantly with hypergravity treatment at 40G for 2 h, and decreased with microgravity treatment at almost 0G for 1,2 h. Collagen mRNA levels were also altered, although changes were slower and less pronounced compared with those for HSP47. The gravity-regulated HSP47 may play a role in the maintenance of the extracellular matrix by modulating collagen production at the primary stage of adaptation. [source] Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin,INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 3 2005L. R. Robinson Synopsis The palmitoyl pentapeptide palmitoyl-lysine-threonine-threonine-lysine-serine (pal-KTTKS) is a synthetic material that was designed as a topical agent to stimulate collagen production and thus provide a skin anti-wrinkle benefit. To determine if pal-KTTKS is effective, the clinical study reported here was conducted. Caucasian female subjects (n = 93, aged 35,55) participated in a 12-week, double-blind, placebo-controlled, split-face, left,right randomized clinical study assessing two topical products: moisturizer control product vs. the same moisturizer product containing 3 ppm pal-KTTKS. Pal-KTTKS was well tolerated by the skin and provided significant improvement vs. placebo control for reduction in wrinkles/fine lines by both quantitative technical and expert grader image analysis. In self-assessments, subjects also reported significant fine line/wrinkle improvements and noted directional effects for other facial improvement parameters. Résumé Le pentapeptide palmitoyl-lysine-thréonine-lysine-sérine (pal-KTTKS) est un composé synthétique décrit comme agent topique stimulant la production de collagène et possédant donc des propriétés anti-rides. L'efficacité du pal-KTTKL a étéévaluée dans l'étude clinique faisant l'objet de cet article. Des femmes de type caucasien (n = 93, de 35 à 55 ans) ont participé pendant 12 semaines à un test en double aveugle avec placébo, en apparié par demie face comparant deux produits topiques: un produit témoin hydratant et le même produit contenant 3 ppm de pal-KTTKS. Bien toléré par la peau, le pal-KTTKS a montré par rapport au témoin, une amélioration significative dans la réduction des rides et ridules que se soit par des techniques quantitatives et par l'analyse d'image quantifiée par un expert. Dans le cadre d'auto-évaluations, les sujets ont fait état d'améliorations significatives et attiré l'attention sur des effets pouvant servir de pistes pour d'autres paramètres d'amélioration faciale. [source] Effects of sevoflurane on collagen production and growth factor expression in rats with an excision woundACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2010H.-J. LEE Background: Sevoflurane is a widely used inhalation anesthetic, but there are no studies on its effect on the wound-healing process. This study was undertaken to evaluate the effect of exposure time to sevoflurane on wound healing. Method: Male Sprague,Dawley rats were used. Two circular full-thickness skin defects 8 mm in diameter were made on the dorsum of the rats. The animals were divided into six groups according to exposed gas type and time: S1 (sevoflurane, 1 h), S4 (sevoflurane, 4 h), S8 (sevoflurane, 8 h), O1 (oxygen, 1 h), O4 (oxygen, 4 h), and O8 (oxygen, 8 h). The surface area of the wounds was measured 0, 1, 3, and 7 days after surgery. Separately, the mean blood pressures (MBP) and arterial oxygen pressures (PaO2) were monitored during the sevoflurane exposure. Collagen type I production and transforming growth factor-,1 (TGF-,1) and basic fibroblast growth factor (bFGF) expression on the wound surface were analyzed. Routine histological analysis was also performed. Result: Exposure duration to sevoflurane had no influence on MBP and PaO2. The reduction in wound size and collagen type I production was delayed in S8. The expression of TGF-,1 and bFGF on the wound surface in S8 was significantly attenuated in S8. The histology of the S8 demonstrated a delayed healing status. Conclusions: Prolonged exposure to sevoflurane might alter the inflammatory phase of the wound-healing process by attenuation of growth factor expression such as TGF-,1 and bFGF and subsequently by reduced collagen production. [source] The characterization and optimization of injectable silicone resin particles in conjunction with dermal fibroblasts and growth factors: An in vitro studyJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2010Robert M. Crews Abstract Minimally invasive subdermal injection of liquid silicone has been used clinically to augment the soft tissue of the foot to mitigate high pressures that cause diabetic foot ulcers. However, implant migration has been a clinical issue. The objective of this study was to assess the effects of three specific concentrations of silicone resin particles (12 ,m average diameter) in conjunction with either platelet-derived growth factor (PDGF-BB) or basic fibroblast growth factor (bFGF) on fibroblast cell proliferation, collagen synthesis, cell morphology, and migration through in vitro assays and a monolayer scratch wound model. PDGF and bFGF enhanced the proliferation of fibroblasts 5.7-fold and fivefold, respectively, while the addition of silicone particles had no significant effect on proliferation. Collagen production was increased approximately twofold with the addition of bFGF and the medium concentration of particles over bFGF without particles and the PDGF groups. The addition of silicone particles had no significant effect on collagen production compared with control groups without particles. Fibroblast migration was enhanced by the addition of both PDGF and bFGF compared to controls, although slower scratch wound closure rates were observed in the presence of particles compared to controls without particles. Cell morphology suggested that particles induced cellular aggregation encircling silicone particles postwounding as well as migration into the wound area. These results suggest that silicone particles in combination with a growth factor might enhance fibroblast aggregation and implant stability, and could promote connective tissue ingrowth and implant encapsulation in the soft tissue of the diabetic foot. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010 [source] Diosmetin Induces Human Osteoblastic Differentiation Through the Protein Kinase C/p38 and Extracellular Signal-Regulated Kinase 1/2 Pathway,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2008Ya-Ling Hsu Abstract Introduction: The survival of osteoblasts is one of the determinants of the development of osteoporosis. This study is the first to investigate the osteoblastic differentiation induced by diosmetin, a flavonoid derivative, in osteoblastic cell lines MG-63, hFOB, and MC3T3-E1 and bone marrow stroma cell line M2-10B4. Materials and Methods: Osteoblastic differentiation was determined by assaying alkaline phosphatase (ALP) activity and mineralization degree and measuring various osteoblast-related markers using ELISA. Expression and phosphorylation of Runt-related transcription factor 2 (Runx2), protein kinase C, (PKC,), extracellular signal-regulated kinase (ERK), p38, and c- jun -N-terminal kinase (JNK) was assessed by immunoblot. Rac1 activity was determined by immunoprecipitation, and Runx2 activity was assessed by EMSA. Genetic inhibition was performed by small hairpin RNA plasmids or small interfering RNA (siRNA) transfection. Results: Diosmetin exhibited an effect on osteoblastic maturation and differentiation by means of ALP activity, osteocalcin, osteopontin, and type I collagen production, as well as Runx2 upregulation. Induction of differentiation by diosmetin was associated with increased PKC, phosphorylation and the activations of Rac1 and p38 and ERK1/2 kinases. Blocking PKC, by siRNA inhibition significantly decreased osteoblastic differentiation by inhibiting Rac1 activation and subsequently attenuating the phosphorylation of p38 and ERK1/2. In addition, blocking p38 and ERK1/2 by siRNA transfection also suppressed diosmetin-induced cell differentiation. Conclusions: In this study, we show that diosmetin induced osteoblastic differentiation through the PKC,-Rac1-MEK3/6-p38 and PKC,-Rac1-MEK1/2- ERK1/2-Runx2 pathways and that it is a promising agent for treating osteoporosis. [source] Positive Linear Growth and Bone Responses to Growth Hormone Treatment in Children With Types III and IV Osteogenesis Imperfecta: High Predictive Value of the Carboxyterminal Propeptide of Type I Procollagen,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2003Joan C Marini MD Abstract Extreme short stature is a cardinal feature of severe osteogenesis imperfecta (OI), types III and IV. We conducted a treatment trial of growth hormone in children with OI and followed linear growth velocity, bone metabolism markers, histomorphometrics, and vertebral bone density. Twenty-six children with types III and IV OI, ages 4.5,12 years, were treated with recombinant growth hormone (rGH), 0.1,0.2 IU/kg per day for 6 days/week, for at least 1 year. Length, insulin-like growth factor (IGF-I), insulin-like growth factor binding protein (IGFBP-3), bone metabolic markers, and vertebral bone density by DXA were evaluated at 6-month intervals. An iliac crest biopsy was obtained at baseline and 12 months. Approximately one-half of the treated OI children sustained a 50% or more increase in linear growth over their baseline growth rate. Most responders (10 of 14) had moderate type IV OI. All participants had positive IGF-I, IGFBP-3, osteocalcin, and bone-specific alkaline phosphatase responses. Only the linear growth responders had a significant increase in vertebral DXA z-score and a significant decrease in long bone fractures. After 1 year of treatment, responders' iliac crest biopsy showed significant increases in cancellous bone volume, trabecular number, and bone formation rate. Responders were distinguished from nonresponders by higher baseline carboxyterminal propeptide (PICP) values (p < 0.05), suggesting they have an intrinsically higher capacity for collagen production. The results show that growth hormone can cause a sustained increase in the linear growth rate of children with OI, despite the abnormal collagen in their bone matrix. In the first year of treatment, growth responders achieve increased bone formation rate and density, and decreased fracture rates. The baseline plasma concentration of PICP was an excellent predictor of positive response. [source] Inhibition of osteoblast function in vitro by aminobisphosphonatesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2009Isabel R. Orriss Abstract Bisphosphonates are analogues of pyrophosphate, a key physicochemical inhibitor of mineralisation. We examined the direct actions of bisphosphonates on the function of cultured osteoblasts derived from rat calvariae. Treatment with zoledronate, the most potent bisphosphonate studied, reduced osteoblast number at concentrations ,100 nM and was strongly toxic at 10 µM, causing a threefold decrease in osteoblast viability after 2 days and a 90% decrease in cell numbers after 14 days. In control osteoblast cultures on plastic, abundant formation of ,trabecular' mineralised bone matrix nodules began after 10 days. Continuous exposure to zoledronate inhibited bone mineralisation at concentrations as low as 10 nM. Pamidronate and clodronate exerted similar effects but at higher doses (,1 and ,10 µM, respectively). Short-term or intermittent exposure of osteoblasts to zoledronate and pamidronate (1,10 µM) was sufficient to inhibit bone mineralisation by ,85%. Zoledronate but not pamidronate or clodronate also strongly inhibited osteoblast alkaline phosphatase activity at concentrations ,100 nM and soluble collagen production at concentrations ,1 µM. We additionally studied the effects of zoledronate on osteoblasts cultured on dentine, a bone-like mineralised substrate, observing similar inhibitory effects, although at concentrations 10,100-fold higher; this shift presumably reflected adsorption of zoledronate to dentine mineral. Thus, zoledronate blocked bone formation in two ways: first, a relatively non-toxic, selective inhibition of mineralisation at concentrations in the low nanomolar range and second, a cytotoxic inhibition of osteoblast growth and function at concentrations ,1 µM. Although no data are available on the bisphosphonate concentrations that osteoblasts could be exposed to in vivo, our results are consistent with earlier observations that bisphosphonates may inhibit bone formation. J. Cell. Biochem. 106: 109,118, 2009. © 2008 Wiley-Liss, Inc. [source] B-type natriuretic peptide and extracellular matrix protein interactions in human cardiac fibroblastsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2010Brenda K. Huntley Cardiac fibroblasts (CFs) regulate myocardial remodeling by proliferating, differentiating, and secreting extracellular matrix (ECM) proteins. B-type natriuretic peptide (BNP) is anti-fibrotic, inhibits collagen production, augments matrix metalloproteinases, and suppresses CF proliferation. Recently, we demonstrated that the ECM protein fibronectin (FN) augmented production of BNP's second messenger, 3,, 5, cyclic guanosine monophosphate (cGMP) in CFs, supporting crosstalk between FN, BNP, and its receptor, natriuretic peptide receptor A (NPR-A). Here, we address the specificity of FN to augment cGMP generation by investigating other matrix proteins, including collagen IV which contains RGD motifs and collagen I and poly- L -lysine, which have no RGD domain. Collagen IV showed increased cGMP generation to BNP similar to FN. Collagen I and poly- L -lysine had no effect. As FN also interacts with integrins, we then examined the effect of integrin receptor antibody blockade on BNP-mediated cGMP production. On FN plates, antibodies blocking RGD-binding domains of several integrin subtypes had little effect, while a non-RGD domain interfering integrin ,v,3 antibody augmented cGMP production. Further, on uncoated plates, integrin ,v,3 blockade continued to potentiate the BNP/cGMP response. These studies suggest that both RGD containing ECM proteins and integrins may interact with BNP/NPR-A to modulate cGMP generation. J. Cell. Physiol. 225: 251,255, 2010. © 2010 Wiley-Liss, Inc. [source] Copper stimulates human oral fibroblasts in vitro: a role in the pathogenesis of oral submucous fibrosisJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 8 2001C. Trivedy Abstract: Copper is implicated in the pathogenesis of several fibrotic disorders. Areca nut has been shown to have a high copper content and areca chewing is associated with oral submucous fibrosis (OSF). The effects of copper on human oral fibroblasts were investigated in vitro. Human oral fibroblasts were incubated with copper chloride (CuCl2) at concentrations ranging from 0.01 ,M to 500 ,M for 24 h, and in vitro cell proliferation was assayed by incorporation of tritiated,thymidine; soluble and non-soluble collagen synthesis was assayed using tritiated-proline. Addition of copper chloride at concentrations ranging from 0.1 ,M to 50 ,M increased the collagen synthesis by the oral fibroblasts compared with growth without copper (P<0.05). The addition of copper chloride neither increased the synthesis of non-collagenous proteins by the fibroblasts nor influenced their proliferation rate. We conclude that copper upregulates collagen production in oral fibroblasts. This appears to be concentration dependent, with peak collagen synthesis at 50 ,M CuCl2. These in vitro results taken together with the recent findings of copper in oral biopsies from OSF subjects support the hypothesis that copper in areca nut acts as a mediator of OSF. [source] Flutamide inhibits nifedipine- and interleukin-1,-induced collagen overproduction in gingival fibroblastsJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2010H.-K. Lu Lu H-K, Tseng C-C, Lee Y-H, Li C-L, Wang L-F. Flutamide inhibits nifedipine- and interleukin-1,-induced collagen overproduction in gingival fibroblasts. J Periodont Res 2010; 45: 451,457. © 2010 John Wiley & Sons A/S Background and Objective:, To understand the role of the androgen receptor in gingival overgrowth, the effects of flutamide on interleukin-1,- and nifedipine-induced gene expression of connective tissue growth factor (CTGF/CCN2) and collagen production in gingival fibroblasts were examined. Material and Methods:, Gingival fibroblasts from healthy subjects and patients with dihydropyridine-induced gingival overgrowth (DIGO) were used. Confluent cells were treated with nifedipine, interleukin-1, or both. The mRNA expression was examined using real-time polymerase chain reaction, and the concentration of total soluble collagen in conditioned media was analysed by Sircol Collagen Assay. In addition, the protein expressions of androgen receptor, CTGF/CCN2 and type I collagen in gingival tissue were determined by western blot. Results:, Interleukin-1, was more potent than nifedipine in stimulating CTGF/CCN2 and procollagen ,1(I) mRNA expression, and there was an additive effect of the two drugs. Healthy cells exhibited an equal or stronger response of procollagen ,1(I) than those with DIGO, but DIGO cells displayed a stronger response in the secretion of soluble collagen in the same conditions. Flutamide, an androgen receptor antagonist, inhibited stimulation by nifedipine or interleukin-1,. Additionally, the protein expressions of androgen receptor and type I collagen were higher in DIGO gingival tissue than those in healthy gingival tissue. Conclusion:, The data suggest that both nifedipine and interleukin-1, play an important role in DIGO via androgen receptor upregulation and that gingival overgrowth is mainly due to collagen accumulation. Flutamide decreases the gene expression and protein production of collagen from dihydropyridine-induced overgrowth cells. [source] Aesthetic effects of topical photodynamic therapyJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 11 2010E Kohl Abstract Topical photodynamic therapy has shown to be effective for the treatment of several aspects of skin ageing. Multiple studies have demonstrated improvement of fine wrinkles, mottled hyperpigmentation, tactile roughness and sallowness. These results are supported by immunohistochemical analysis that revealed both upregulation of collagen production and increased epidermal proliferation. Neocollagenesis as an indirect dermal effect of photodynamic therapy is stimulated through cytokine induction. This article reviews the available literature for photodynamic rejuvenation while discussing cosmetic effects, light sources, adverse effects and the mechanism of action. [source] The influence of endothelial cells on the ECM composition of 3D engineered cardiovascular constructs,JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 1 2009Rolf A. A. Pullens Abstract Tissue engineering of small diameter (<5 mm) blood vessels is a promising approach to develop viable alternatives for autologous vascular grafts. Development of a functional, adherent, shear resisting endothelial cell (EC) layer is one of the major issues limiting the successful application of these tissue engineered grafts. The goal of the present study was to create a confluent EC layer on a rectangular 3D cardiovascular construct using human venous cells and to determine the influence of this layer on the extracellular matrix composition and mechanical properties of the constructs. Rectangular cardiovascular constructs were created by seeding myofibroblasts (MFs) on poly(glycolic acid) poly-4-hydroxybutyrate scaffolds using fibrin gel. After 3 or 4 weeks, ECs were seeded and co-cultured using EGM-2 medium for 2 or 1 week, respectively. A confluent EC layer could be created and maintained for up to 2 weeks. The EGM-2 medium lowered the collagen production by MFs, resulting in weaker constructs, especially in the 2 week cultured constructs. Co-culturing with ECs slightly reduced the collagen content, but had no additional affect on the mechanical performance. A confluent endothelial layer was created on 3D human cardiovascular constructs. The layer was co-cultured for 1 and 2 weeks. Although, the collagen production of the MFs was slightly lowered, co-culturing ECs for 1 week results in constructs with good mechanical properties and a confluent EC layer. Copyright © 2008 John Wiley & Sons, Ltd. [source] Photodamage therapy using an electro-optic q-switched Nd:YAG laserLASERS IN SURGERY AND MEDICINE, Issue 8 2010Dina Yaghmai MD Abstract Background and Objective Q-Switched Nd:YAG lasers produce photoacoustic effects in addition to photothermal effects which may allow for greater tissue collagen production. The objective of the study is to determine the effectiveness and tolerability of an Electro-Optic (EO) Q-switched Nd:YAG laser with Single Pulse and novel Double Pulse (DP) options in the treatment of photodamaged skin. Materials and Methods Sixteen subjects with photoaging were enrolled in this prospective, randomized, split-faced study. Subjects received 6 bi-weekly laser treatments. One half of the face was treated with a Single Pulse while the other half was treated with energies divided into a DP. Blinded investigators and subjects assessed improvement after the sixth treatment for wrinkles, coarseness, pigmentation, redness, laxity, comedones, pore size, and overall skin condition. Subjects also rated the tolerability of the treatments. Results For the Single Pulse side of the face, the investigators rated 33% of the patients as having a good to excellent (51% or greater) improvement in the overall condition of the skin while 47% of the subjects reported these levels. On the DP side, the overall improvement was good to excellent at a 27% rate by the investigators and 54% by the subjects. Distributions of improved ratings among investigators and subjects were similar for both sides of the treatment area. The majority of stinging/burning sensations during treatment were reported as mild on the DP side (62.8%) and moderate (63.8%) on the Single Pulse side. The chance of reporting none or only mild stinging/burning sensation during treatment was four times greater on the side of the face treated with the DP (P,<,0.0001). Conclusions Results have shown that treatment with the EO QS Nd:YAG laser provides a safe and effective method of skin rejuvenation with the additional benefit of significantly lower patient discomfort during use of the DP mode. Lasers Surg. Med. 42:699,705, 2010 © 2010 Wiley-Liss, Inc. [source] Development of Electrospun Three-arm Star Poly(, -caprolactone) Meshes for Tissue Engineering ApplicationsMACROMOLECULAR BIOSCIENCE, Issue 8 2010Dario Puppi Abstract We have developed three-dimensional electrospun microfibrous meshes of a novel star branched three-arm poly(, -caprolactone) (*PCL) as potential scaffolds for tissue engineering applications. The processing conditions required to obtain uniform fibers were optimized by studying their influence on fiber morphology and size. Polymer molecular weight and solution feed rate influenced both the mesh microstructure and the tensile properties of the developed mats. Electrospun samples were also tested for their mechanical properties in wet conditions, showing higher yield strength and strain in comparison to that observed in dry conditions. Cell culture experiments employing MC3T3-E1 osteoblast like cells showed good cell viability adhesion and collagen production on the *PCL scaffolds. [source] Mast cell adhesion to bronchial smooth muscle in asthma specifically depends on CD51 and CD44 variant 6ALLERGY, Issue 8 2010P.-O. Girodet To cite this article: Girodet P-O, Ozier A, Trian T, Begueret H, Ousova O, Vernejoux J-M, Chanez P, Marthan R, Berger P, Tunon de Lara JM. Mast cell adhesion to bronchial smooth muscle in asthma specifically depends on CD51 and CD44 variant 6. Allergy 2010; 65: 1004,1012. Abstract Background:, Mast cells infiltrate the bronchial smooth muscle (BSM) in asthmatic patients, but the mechanism of mast cell adhesion is still unknown. The adhesion molecules CD44 (i.e. hyaluronate receptor) and CD51 (i.e. vitronectin receptor) are widely expressed and bind to many extracellular matrix (ECM) proteins. The aims of the study are (i) to identify the role of ECM in mast cell adhesion to BSM and (ii) to examine the role of CD51 and CD44 in this adhesion. Methods:, Human lung mast cells, human mast cell line (HMC-1), and BSM cells from control donors or asthmatic patients were cultured in the presence/absence of various cytokines. Mast cell,BSM interaction was assessed using 3H-thymidine-pulsed mast cells, confocal immunofluorescence, or electron microscopy. Adhesion molecules expression and collagen production on both cell types were evaluated by quantitative RT-PCR, western blot, and flow cytometry. Results:, Mast cell adhesion to BSM cells mostly involved type I collagen of the ECM. Such an adhesion was increased in normal BSM cells under inflammatory condition, whereas it was maximal in asthmatic BSM cells. Blockade of either CD51 or CD44 significantly decreased mast cell adhesion to BSM. At the molecular level, protein and the transcriptional expression of type I collagen, CD51 or CD44 remained unchanged in asthmatic BSM cells or in mast cells/BSM cells under inflammatory conditions, whereas that of CD44 variant isoform 6 (v6) was increased. Conclusions:, Mast cell,BSM cell adhesion involved collagen, CD44, and CD51, particularly under inflammatory conditions. CD44v6 expression is increased in asthmatic BSM cells. [source] Roxithromycin inhibits transforming growth factor-, production by cultured human mesangial cellsNEPHROLOGY, Issue 6 2006HIDEAKI YAMABE SUMMARY: Background: Transforming growth factor-, (TGF-,) plays an important role in progression of renal injury. However, few materials which inhibit TGF-, have been known. Roxithromycin (ROX), macrolide antibiotics, is known to have anti-inflammatory, immunomodulatory and tissue reparative effects besides its bacteriostatic activity, although the exact mechanism of its anti-inflammatory and immunomodulatory effects was not defined. We examined the effect of ROX on production of TGF-, and type IV collagen by cultured human mesangial cells (HMC). Methods: Human mesangial cells were incubated with several concentrations of ROX and TGF-, and type IV collagen levels in the culture supernatants were measured by enzyme-linked immunoassay. Amount of TGF-, mRNA was also quantified by using a colourimetric mRNA quantification kit and semiquantitative reverse transcriptase polymerase chain reaction. We also examined the effect of ROX on tyrosine kinase, MAP kinase and NF-,B stimulated by thrombin. Results: Roxithromycin (0.1,10.0 µg/mL) inhibited TGF-, production by HMC in a dose- and time-dependent manner without inducing cell injury. ROX (10.0 µg/mL) also inhibited mRNA expression of TGF-, in HMC. Thrombin (5 U/mL) stimulated TGF-, production by HMC and ROX significantly inhibited the stimulating effect of thrombin on TGF-, production. ROX also inhibited the increment of type IV collagen production stimulated by thrombin. ROX (10.0 µg/mL) suppressed the thrombin-induced NF-,B activation, although ROX did not inhibit the activation of tyrosine kinase and MAP kinase by thrombin. Conclusion: Roxithromycin has an inhibitory effect on TGF-, production by HMC possibly via inhibition of NF-,B. ROX may be a potential agent for the treatment of glomerulosclerosis. [source] Effect of a novel botanical agent Drynol Cibotin on human osteoblast cells and implications for osteoporosis: promotion of cell growth, calcium uptake and collagen productionPHYTOTHERAPY RESEARCH, Issue S2 2010Barbara Wegiel Abstract Osteoporosis is a widespread problem afflicting millions of people. Drynol Cibotinis is a newly developed proprietary botanical combination of eight botanicals including Angelica sinensis, Glycine max, Wild yam, Ligustrum lucidum, Astragalus membranaceus, Cuscuta chinensis, Psoraleae corylifoliae, and Drynaria fortune. Each of the botanicals has been used in traditional Chinese medicine to treat osteoporosis. The effect of Drynol Cibotinis, with the specific combination of these anti-osteoporosis botanicals for promoting bone growth, was examined in this study. The effects of Drynol Cibotin on cell growth, apoptosis, cell spreading, calcium uptake and production of bone matrix proteins Collagen I and Laminin B2 on human osteoblast cells were assessed by BrdU incorporation, TUNEL assay, cell staining, intracellular Ca2+ measurement and Western blot analysis. The results showed that Drynol Cibotin significantly increased cell proliferation and inhibited apoptosis in osteoblasts (P < 0.01). In addition, Drynol Cibotin was found to promote cell spreading and greatly increase calcium uptake both instantaneously and in the long term (P < 0.01). Furthermore, Drynol Cibotin significantly increased production of two key extracellular matrix proteins in bone cells: Collagen I and Laminin B2. These results indicate that Drynol Cibotin alone or in combination with amino acids and vitamins may have prophylactic potentials in osteoporosis. Copyright © 2009 John Wiley & Sons, Ltd. [source] Smad3 signalling plays an important role in keloid pathogenesis via epithelial,mesenchymal interactionsTHE JOURNAL OF PATHOLOGY, Issue 2 2005TT Phan Abstract Smad signalling plays important roles in developmental and cancer biology as well as in fibropathogenesis. Its role in keloid biology is not known. Epithelial,mesenchymal interactions, originally described in normal skin, have recently been established to play a significant role in keloid pathogenesis, and demonstrate the important influence of keratinocyte paracrine factor signalling on fibroblast behaviour. The present study investigated the role of downstream Smad cascade induction in this interaction. Normal fibroblasts (NF) and keloid fibroblasts (KF) were co-cultured in serum-free medium with normal keratinocytes (NK) or keloid keratinocytes (KK) for 5 days, after which fibroblast cell lysates were subjected to western blot and immunoprecipitation analysis to quantify the levels of Smad and Smad2/3/4 binding complex. In another set of experiments, wild-type (wt), Smad2-null (Smad2,/,) and Smad3-null (Smad3,/,) mouse embryonic fibroblasts (MEF) were assayed for cell proliferation and collagen production after serum-free co-culture with KK or exposure to conditioned media collected from serum-free KK/KF co-culture. Compared to normal skin, keloids expressed high basal levels of TGF,R1 and TGF,R2, Smad2, 3 and 4 and phospho-Smad2. Upregulation of TGF,R1 and TGF,R2, Smad3 and p-Smad2 was observed in KF co-cultured with KK, together with enhanced Smad3 phosphorylation and Smad2/3/4 binding complex production. When MEF-wt, MEF-Smad2,/, or MEF-Smad3,/, were co-cultured with KK or exposed to KK/KF co-culture conditioned media, enhanced proliferation and collagen production were seen in MEF-wt and MEF-Smad2,/, but not in MEF-Smad3,/, cells. The activation of Smad signalling, importantly that of Smad3, appears to be one facet of the complex epithelial,mesenchymal interactions in keloid pathogenesis, resulting in active KF proliferation and collagen-ECM production in co-culture with KK. This finding suggests the suppression of Smad signalling as a novel approach in keloid therapy. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Treatment with rapamycin prevents fibrosis in tight-skin and bleomycin-induced mouse models of systemic sclerosisARTHRITIS & RHEUMATISM, Issue 8 2010Ayumi Yoshizaki Objective Rapamycin, a novel macrolide immunosuppressive drug, is increasingly used as an agent for posttransplant immunosuppression and treatment of autoimmune disease. The molecular mechanism related to rapamycin-mediated immunosuppression is that rapamycin binds to FK-506 binding protein 12, and the formed complex inhibits the function of the mammalian target of rapamycin (mTOR), which in turn reduces protein phosphorylation, cell cycle progression, and cytokine production. The aim of this study was to examine the effect of rapamycin against the development of fibrosis and autoimmunity in 2 different types of systemic sclerosis (SSc) model mice. Methods Tight skin (TSK/+) mice and bleomycin- induced SSc model mice were used to evaluate the effect of rapamycin on fibrosis and immunologic abnormalities. Furthermore, the antifibrotic effect of rapamycin was assessed using TSK/+ mouse fibroblasts. Results Treatment with rapamycin reduced skin fibrosis of TSK/+ mice and skin and lung fibrosis of bleomycin-induced SSc model mice. The production of fibrogenic cytokines, such as interleukin-4 (IL-4), IL-6, IL-17, and transforming growth factor ,1, was attenuated by rapamycin. Hypergammaglobulinemia and anti,topoisomerase I antibody production were also reduced by rapamycin treatment in TSK/+ mice. In addition, mTOR expression levels were increased in TSK/+ mouse fibroblasts compared with those in wild-type mouse fibroblasts. Rapamycin treatment inhibited proliferation and collagen production of TSK/+ mouse fibroblasts in a dose-dependent manner. Conclusion This study is the first to show that rapamycin has a significant inhibitory effect on fibrosis in both TSK/+ and bleomycin-induced SSc model mice. These results suggest that rapamycin might be an attractive candidate for clinical trials in SSc patients. [source] Intracellular Na+ and Ca2+ modulation increases the tensile properties of developing engineered articular cartilageARTHRITIS & RHEUMATISM, Issue 4 2010Roman M. Natoli Objective Significant collagen content and tensile properties are difficult to achieve in tissue-engineered articular cartilage. The aim of this study was to investigate whether treating developing tissue-engineered cartilage constructs with modulators of intracellular Na+ or Ca2+ could increase collagen concentration and construct tensile properties. Methods Inhibitors of Na+ ion transporters and stimulators of intracellular Ca2+ were investigated for their ability to affect articular cartilage development in a scaffoldless, 3-dimensional chondrocyte culture. Using a systematic approach, we applied ouabain (Na+/K+ -ATPase inhibitor), bumetanide (Na+/K+/2Cl, tritransporter inhibitor), histamine (cAMP activator), and ionomycin (a Ca2+ ionophore) to tissue-engineered constructs for 1 hour daily on days 10,14 of culture and examined the constructs at 2 weeks or 4 weeks. The gross morphology, biochemical content, and compressive and tensile mechanical properties of the constructs were assayed. Results The results of these experiments showed that 20 ,M ouabain, 0.3 ,M ionomycin, or their combination increased the tensile modulus by 40,95% compared with untreated controls and resulted in an increased amount of collagen normalized to construct wet weight. In constructs exposed to ouabain, the increased percentage of collagen per construct wet weight was secondary to decreased glycosaminoglycan production on a per-cell basis. Treatment with 20 ,M ouabain also increased the ultimate tensile strength of neo-tissue by 56,86% at 4 weeks. Other construct properties, such as construct growth and type I collagen production, were affected differently by Na+ modulation with ouabain versus Ca2+ modulation with ionomycin. Conclusion These data are the first to show that treatments known to alter intracellular ion concentrations are a viable method for increasing the mechanical properties of engineered articular cartilage and identifying potentially important relationships to hydrostatic pressure mechanotransduction. Ouabain and ionomycin may be useful pharmacologic agents for increasing tensile integrity and directing construct maturation. [source] Loss of ,1 integrin in mouse fibroblasts results in resistance to skin scleroderma in a mouse modelARTHRITIS & RHEUMATISM, Issue 9 2009Shangxi Liu Objective Activated adhesive signaling is a hallmark of fibroblasts isolated from the scars of scleroderma (systemic sclerosis) lesions. Beta-1 integrin plays a key role in adhesive signaling. The aim of the present study was to examine the role of ,1 integrin in a mouse model of skin scleroderma using mice bearing a fibroblast-specific deletion of ,1 integrin. Methods Cutaneous sclerosis was induced by subcutaneous injection of bleomycin. Control groups were treated with phosphate buffered saline. Mice bearing a fibroblast-specific deletion of ,1 integrin and control mice were investigated. Dermal thickness, collagen production, and the number of ,-smooth muscle actin,positive cells were determined. The quantity of the collagen-specific amino acid hydroxyproline was also measured. Results Bleomycin treatment induced marked cutaneous thickening and fibrosis in control mice. Conversely, the deletion of ,1 integrin resulted in resistance to bleomycin-induced fibrosis. Conclusion Expression of ,1 integrin by fibroblasts is required for fibrogenesis. Inhibition of ,1 integrin may be a viable method to alleviate the development of cutaneous sclerosis. [source] Altered mineralization of human osteoarthritic osteoblasts is attributable to abnormal type I collagen productionARTHRITIS & RHEUMATISM, Issue 5 2009Denis Couchourel Objective Bone tissue in osteoarthritis (OA) is composed of abundant undermineralized osteoid matrix. The aim of this study was to investigate the mechanisms responsible for this abnormal matrix, using in vitro OA subchondral osteoblasts. Methods Primary normal and OA osteoblasts were prepared from tibial plateaus. Phenotype was determined by alkaline phosphatase activity, and osteocalcin, osteopontin, prostaglandin E2 (PGE2), and transforming growth factor ,1 (TGF,1) were assessed by enzyme-linked immunosorbent assay. Expression of COL1A1 and COL1A2 was determined by real-time polymerase chain reaction. The production of type I collagen was determined by the release of its C-terminal propeptide and Western blot analysis. In vitro mineralization was evaluated by alizarin red staining. Inhibition of TGF,1 expression was performed using a small interfering RNA technique. Results Mineralization of OA osteoblasts was reduced compared with mineralization of normal osteoblasts, even in the presence of bone morphogenetic protein 2 (BMP-2). Alkaline phosphatase and osteocalcin levels were elevated in OA osteoblasts compared with normal osteoblasts, whereas osteopontin levels were similar. The COL1A1 -to- COL1A2 messenger RNA ratio was 3-fold higher in OA osteoblasts compared with normal osteoblasts, and the production of collagen by OA osteoblasts was increased. Because TGF,1 inhibits BMP-2,dependent mineralization, and because TGF,1 levels are ,4-fold higher in OA osteoblasts than in normal osteoblasts, inhibiting TGF,1 levels in OA osteoblasts corrected the abnormal COL1A1 -to- COL1A2 ratio and increased alizarin red staining. Conclusion Elevated TGF,1 levels in OA osteoblasts are responsible, in part, for the abnormal ratio of COL1A1 to COL1A2 and for the abnormal production of mature type I collagen. This abnormal COL1A1 -to- COL1A2 ratio generates a matrix that blunts mineralization in OA osteoblasts. [source] Involvement of the notch pathway in the regulation of matrix metalloproteinase 13 and the dedifferentiation of articular chondrocytes in murine cartilageARTHRITIS & RHEUMATISM, Issue 2 2009Régis Blaise Objective To demonstrate the activation of the Notch signaling pathway during changes in the phenotype of chondrocytes in vitro, and to assess the influence of Notch on the production of chondrocyte markers. Methods Serial monolayer primary cultures of murine articular chondrocytes (MACs), as a model of chondrocyte dedifferentiation, were prepared. MACs were cultured with or without a Notch inhibitor and transfected with different Notch -expressing vectors. The Notch pathway and chondrocyte marker profiles were assessed by quantitative reverse transcription,polymerase chain reaction, immunoblotting, and immunocytochemistry. Results Successive passages of MACs resulted in a loss of type II collagen and aggrecan (chondrocyte differentiation markers), an increase in type I collagen (dedifferentiation marker), an increase in Notch ligands, and augmented target gene activity. The Notch inhibitor decreased the type II collagen protein content but had no effect on Col2a1 messenger RNA, while transfection with the constitutive active forms of the Notch1 receptor led to a decrease in type II collagen in transfected cells. In assays to investigate the mechanism of type II collagen breakdown, matrix metalloproteinase 13 (MMP-13) synthesis was regulated in a Notch-dependent manner, whereas MMP-2 synthesis was unchanged. Conclusion The Notch signaling pathway is associated with decreased type II collagen production during the dedifferentiation of MACs in vitro. This may be correlated with the increase in MMP-13 production linked to activation of Notch. [source] Adenosine A2A receptors in diffuse dermal fibrosis: Pathogenic role in human dermal fibroblasts and in a murine model of sclerodermaARTHRITIS & RHEUMATISM, Issue 8 2006E. S. L. Chan Objective Adenosine regulates inflammation and tissue repair, and adenosine A2A receptors promote wound healing by stimulating collagen matrix production. We therefore examined whether adenosine A2A receptors contribute to the pathogenesis of dermal fibrosis. Methods Collagen production by primary human dermal fibroblasts was analyzed by real-time polymerase chain reaction, 14C-proline incorporation, and Sircol assay. Intracellular signaling for dermal collagen production was investigated using inhibitors of MEK-1 and by demonstration of ERK phosphorylation. In vivo effects were studied in a bleomycin-induced dermal fibrosis model using adenosine A2A receptor,deficient wild-type littermate mice, C57BL/6 mice, and mice treated with adenosine A2A receptor antagonist. Morphometric features and levels of hydroxyproline were determined as measures of dermal fibrosis. Results Adenosine A2A receptor occupancy promoted collagen production by primary human dermal fibroblasts, which was blocked by adenosine A2A, but not A1 or A2B, receptor antagonism. Adenosine A2A receptor ligation stimulated ERK phosphorylation, and A2A receptor,mediated collagen production by dermal fibroblasts was blocked by MEK-1 inhibitors. Adenosine A2A receptor,deficient and A2A receptor antagonist,treated mice were protected from developing bleomycin-induced dermal fibrosis. Conclusion These results demonstrate that adenosine A2A receptors play an active role in the pathogenesis of dermal fibrosis and suggest a novel therapeutic target in the treatment and prevention of dermal fibrosis in diseases such as scleroderma. [source] Induction of prolonged infiltration of T lymphocytes and transient T lymphocyte,dependent collagen deposition in mouse lungs following adenoviral gene transfer of CCL18ARTHRITIS & RHEUMATISM, Issue 8 2006Irina G. Luzina Objective Levels of CCL18 are elevated in patients with scleroderma lung disease and other fibrotic pulmonary diseases associated with T lymphocyte involvement. We sought to determine whether CCL18 alone can induce pulmonary T lymphocytic infiltration and fibrosis in mouse lungs. Methods An adenovirus vector was constructed and used for CCL18 delivery to mouse lungs in vivo. Immunohistochemical, flow cytometric, and enzyme-linked immunosorbent assay analyses were used to assess the resulting changes. Results Overexpression of CCL18 led to massive perivascular and peribronchial infiltration of T lymphocytes. Although the expression of CCL18 peaked on day 7, the infiltration persisted up to day 64 after infection. The infiltrates were negative for proliferating cell nuclear antigen and TUNEL, suggesting the role of cell trafficking, rather than proliferation and apoptosis, in the infiltration dynamics. Patchy destruction of the alveolar architecture and collagen accumulation in association with the infiltrates were also noticed. These changes were infiltration-dependent, rather than CCL18-dependent, since treatment with antilymphocyte serum completely abrogated the CCL18-induced changes. The infiltrates consisted almost exclusively of T lymphocytes that were minimally activated, with a minimal increase in the expression of CD69 and no changes in the expression of CD25, Fas, FasL, or CD40L. There was no increase in total pulmonary levels of profibrotic cytokines transforming growth factor ,1 (TGF,1) or interleukin-13, although active TGF,1 was present locally in association with the infiltrates and areas of distorted alveolar architecture. Prestimulation of primary T lymphocytes with CCL18 in vitro caused an up-regulation of TGF,1 and collagen production in T lymphocyte/fibroblast cocultures. Conclusion CCL18 promotes selective, long-term pulmonary infiltration of T lymphocytes and infiltration-dependent accumulation of collagen through a TGF,1-dependent mechanism. [source] | ||||||||||||||||||||||||||||