Opposite effects of bFGF and TGF-β on collagen metabolism by human periodontal ligament fibroblasts

Periodontal ligament cells mobilized by transforming growth factor-beta 1 and migrated without stimuli showed enhanced osteogenic differentiation

OBJECTIVE

This study aimed to analyze the ability of G-CSF and TGF-β1 to mobilize periodontal ligament stem cells to obtain populations with better potential for proliferation and osteogenic differentiation.

DESIGN

Primary cultures were established from the periodontal ligament of Wistar rats. After a cell migration assay, four experimental groups were obtained: PDLSC, composed of the primary culture, non-mobilized cells; MPDLSC, the spontaneously migrated cells; MPDLSC-GCSF, the cells mobilized with G-CSF; and MPDLSC-TGF-β1, the cells mobilized with TGF-β1. The expression of mesenchymal stem cell markers was assessed by flow cytometry. Clonogenicity, viability, proliferative potential, and osteogenic differentiation capacity were also analyzed.

RESULTS

All the study groups expressed well-known mesenchymal stem cell markers and exhibited clonogenic capacity. The higher proliferation potential was seen in the PDLSC and MPDLSC groups, while the MPDLSC and MPDLSC-TGFβ1 groups showed a higher number of mineralized deposits in vitro and higher ALP activity after osteogenic differentiation induction. Cells of all the groups also expressed mRNA of genes associated with osteogenic differentiation without previous induction.

CONCLUSIONS

Both agents were able to mobilize stem cells from the periodontal ligament, but G-CSF did not show an advantage, whereas TGF-β1 appears to direct the cells towards a state of increased osteogenic differentiation. Furthermore, spontaneous cell migration through a membrane was sufficient to enrich the cell population.

Actin alpha 2, smooth muscle, a transforming growth factor-β1-induced factor, regulates collagen production in human periodontal ligament cells via Smad2/3 pathway

Background/purpose

Actin alpha 2, smooth muscle (ACTA2) is an actin isoform that forms the cytoskeleton. Actin plays a crucial role in numerous cellular functions. ACTA2 is a marker of functional periodontal ligament (PDL) fibroblasts and is upregulated by transforming growth factor-β1 (TGF-β1); however, the underlying function of ACTA2 in PDL tissue is unknown. We aimed to examine the localization and potential function of ACTA2 in PDL tissues and cells.

Materials and methods

RNA expression was determined using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and quantitative RT-PCR. Protein expression was determined using immunofluorescence staining and Western blot analysis. Soluble and insoluble collagen production was examined using the Sircol collagen assay and picrosirius red staining, respectively. Small interfering RNA (siRNA) was used for knockdown assay to examine the effect of ACTA2 in human PDL cells.

Results

ACTA2 expression was observed in human primary PDL cells and PDL cell line (2-23 cells). TGF-β1 upregulated ACTA2, collagen type Ⅰ alpha1 chain (COL1A1), periostin (POSTN), and fibrillin-Ⅰ(FBN1) expression and soluble and insoluble collagen production in 2-23 cells. However, ACTA2 depletion by siRNA strongly suppressed PDL-related gene expression and collagen production compared with those of TGF-β1-stimulated control cells. Furthermore, ACTA2 knockdown significantly suppressed the phosphorylation of Smad2 and Smad3.

Conclusion

ACTA2 plays a crucial role in PDL-related marker expression and collagen production via Smad2/3 phosphorylation. Our findings might contribute to the development of novel and effective periodontal therapies.

Mechanical stretching can modify the papillary dermis pattern and papillary fibroblast characteristics during skin regeneration

Clinical application of mechanical stretching is a reconstructive method for skin repair. Although studies have reported dermal fibroblast heterogeneity, whether stretching affects individual fibroblast subpopulations equally remains unclear. Here, we show the changes in dermal structure and papillary fibroblast (Fp) in regenerated human skin. Exhausted skin regeneration caused dermal-epidermal junction (DEJ) flattening, papillary dermis thinning, and an increase in the type III collagen (COL3)/type I collagen (COL1) ratio with upregulated hallmarks of aging. Well-regenerated skin displayed a notable increase in the Fp population. Consistent changes were observed in the rat expansion model. Moreover, we found that TGFβ1 expression was especially increased in skin showing good regeneration. Activation of the TGFβ1/Smad2/3 pathway improved exhausted skin regeneration and resulted in increased collagen content and Fp proliferation, while pharmacological inhibition of TGFβ1 action impacted well-regenerated skin. Short-term mechanical stretching that promoted skin regeneration enhanced Fp proliferation, extracellular matrix (ECM) synthesis, and increased TGFβ1 expression, leading to good regeneration. Conversely, long-term stretching induced premature Fp senescence, leading to poor regeneration. This work shows the mechanism of mechanical stretching in well skin regeneration that enhances Fp proliferation and ECM synthesis via the TGFβ1/Smad2/3 pathway, and highlights a crucial role of Fps in stretching-induced skin regeneration.

Effects of different methods of demineralized dentin matrix preservation on the proliferation and differentiation of human periodontal ligament stem cells

Background/purpose

Demineralized dentin matrix (DDM) is used as a tissue regeneration scaffold. Effective preservation of DDM benefits clinical applications. Cryopreservation and freeze-drying may be effective methods to retain DDM mechanical properties and biological activity.

Materials and methods

Human periodontal ligament stem cells (hPDLSCs) isolated using enzymatic dissociation were identified by multidirectional differentiation and flow cytometry. DDM was prepared with EDTA and divided into four groups: fresh DDM (fDDM), room temperature-preserved DDM (rtDDM), cryopreserved DDM (cDDM) and freeze-dried DDM (fdDDM). The DDM surface morphology was observed, and microhardness was detected. Transforming growth factor-β1 (TGF-β1), fibroblast growth factor (FGF) and collagen-Ⅰ (COL-Ⅰ) concentrations in DDM liquid extracts were detected by enzyme-linked immunosorbent assay (ELISA). The hPDLSCs were cultured with DDM liquid extracts. The effect of DDM on cells proliferation was examined by CCK-8 assay. The effect of DDM on hPDLSC secreted phosphoprotein-1 (SPP1), periostin (POSTN) and COL-Ⅰ gene expression was examined by real-time qPCR.

Results

cDDM dentinal tubules were larger than those of the other groups. The three storage conditions had no significant effect on DDM microhardness and COL-Ⅰ concentration. However, TGF-β1 and FGF concentrations decreased after storage, with the greatest change in rtDDM, followed by fdDDM and cDDM. The liquid extracts of fDDM, cDDM and fdDDM slightly inhibited hPDLSCs proliferation, but those of rtDDM had no significant effect. The hPDLSCs cultured with fDDM, cDDM and fdDDM liquid extracts showed increased SPP1, POSTN and COL-Ⅰ gene expression.

Conclusion

Cryopreservation and freeze-drying better maintain the mechanical properties and biological activity of DDM.

bFGF stimulated plasminogen activation factors, but inhibited alkaline phosphatase and SPARC in stem cells from apical Papilla: Involvement of MEK/ERK, TAK1 and p38 signaling

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bFGF induced uPA, uPAR, PAI-1 production/expression in SCAP →

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bFGF induced decline of ALP and SPARC of SCAP →

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The effects of bFGF are regulated by ERK, p38, TAK1 and Akt signaling →

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Crucial for SCAP proliferation, matrix turnover and differentiation →

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These events are important for revascularization/root apexogenesis

Introduction

Objectives

Methods

Results

Conclusion

Low Ozone Concentrations Differentially Affect the Structural and Functional Features of Non-Activated and Activated Fibroblasts In Vitro

Oxygen-ozone (O2-O3) therapy is increasingly applied as a complementary/adjuvant treatment for several diseases; however, the biological mechanisms accounting for the efficacy of low O3 concentrations need further investigations to understand the possibly multiple effects on the different cell types. In this work, we focused our attention on fibroblasts as ubiquitous connective cells playing roles in the body architecture, in the homeostasis of tissue-resident cells, and in many physiological and pathological processes. Using an established human fibroblast cell line as an in vitro model, we adopted a multimodal approach to explore a panel of cell structural and functional features, combining light and electron microscopy, Western blot analysis, real-time quantitative polymerase chain reaction, and multiplex assays for cytokines. The administration of O2-O3 gas mixtures induced multiple effects on fibroblasts, depending on their activation state: in non-activated fibroblasts, O3 stimulated proliferation, formation of cell surface protrusions, antioxidant response, and IL-6 and TGF-β1 secretion, while in LPS-activated fibroblasts, O3 stimulated only antioxidant response and cytokines secretion. Therefore, the low O3 concentrations used in this study induced activation-like responses in non-activated fibroblasts, whereas in already activated fibroblasts, the cell protective capability was potentiated.

The Role of Type 2 Fibroblast Growth Factor in Periodontal Therapy

The prevalence of periodontitis is around 20-50% in the global population. If it is not treated, it can cause tooth loss. Periodontal treatment aims at preserving the patient's teeth from various damages, including infection control and restoring lost periodontal tissue. The periodontium has great biological regenerative potential, and several biomaterials can be used to improve the outcome of periodontal treatment. To achieve the goal of periodontal tissue regeneration, numerous studies have used fibroblast growth factor 2 (FGF2) to stimulate the regeneration of both the soft tissue and bone. FGF2 induced a significant increment in the percentage of bone fill, bone mineral levels of the defect sites, length of the regenerated periodontal ligament, angiogenesis, connective tissue formation on the root surface, formation of dense fibers bound to the alveolar bone and newly synthesized cementum in teeth. This review will open further avenues to better understand the FGF2 therapy for periodontal regeneration.

Investigating the effect of antiseptic solution on the release of interleukin-6 and transforming growth factor beta 1 from human gingival fibroblasts using wound healing assays

This in vitro study evaluated the effect of different antiseptics and different concentrations thereof in a model of wound healing using human gingival fibroblasts. The fibroblasts were rinsed with four different antiseptic solutions: sodium hypochlorite (HYP), hydrogen peroxide (H₂O₂), chlorhexidine digluconate (CHX), and benzalkonium chloride (BC). The effect on the release of interleukin-6 (IL-6) and transforming growth factor beta 1 (TGF-β1) was investigated using enzyme-linked immunosorbent assays (ELISAs). In addition, the effects of the antiseptics on wound healing at 1, 12, 24, and 48 h were assessed through a wound healing assay. The viability of the fibroblasts rinsed with antiseptics was investigated with respect to the concentrations inhibiting cell growth by 50% (IC₅₀), 25% (IC₂₅), and ≤2% (IC₂). A statistically significant increased release of IL-6 was obtained with BC IC₂₅ and IC₂ after 12, 24, and 48 h (P < 0.01). For TGF-β1, no significant release was found for CHX IC₂ after 24 and 48 h or for IC₅₀ and IC₂₅ after 12 h. There was no significant effect on wound healing capacity for CHX or for BC IC₂₅ and IC₂. This study demonstrated that antiseptic rinses of human gingival fibroblasts alter the release of IL-6 and TGF-β1 and impact wound healing capacity, with both BC and CHX conferring neutral effects.

Developmental Dysplasia of the Hip: A Review of Etiopathogenesis, Risk Factors, and Genetic Aspects

As one of the most frequent skeletal anomalies, developmental dysplasia of the hip (DDH) is characterized by a considerable range of pathology, from minor laxity of ligaments in the hip joint to complete luxation. Multifactorial etiology, of which the candidate genes have been studied the most, poses a challenge in understanding this disorder. Candidate gene association studies (CGASs) along with genome-wide association studies (GWASs) and genome-wide linkage analyses (GWLAs) have found numerous genes and loci with susceptible DDH association. Studies put major importance on candidate genes associated with the formation of connective tissue (COL1A1), osteogenesis (PAPPA2, GDF5), chondrogenesis (UQCC1, ASPN) and cell growth, proliferation and differentiation (TGFB1). Recent studies show that epigenetic factors, such as DNA methylation affect gene expression and therefore could play an important role in DDH pathogenesis. This paper reviews all existing risk factors affecting DDH incidence, along with candidate genes associated with genetic or epigenetic etiology of DDH in various studies.

Effect of bFGF on the growth and matrix turnover of stem cells from human apical papilla: Role of MEK/ERK signaling

BACKGROUND/PURPOSE

Basic fibroblast growth factor (bFGF) exhibits multiple biological functions in various tissues. Stem cells from apical papilla (SCAP) can be isolated from human apical papilla tissues in developmental teeth of children. The purposes of this study were to investigate the expression of FGF receptors (FGFRs) and the effects of bFGF on SCAP and related MEK/ERK signaling.

METHODS

SCAP cells were treated under different concentrations of bFGF with or without U0126 (an inhibitor of MEK/ERK). Expression of FGFR1 and FGFR2 in SCAP was analyzed by RT-PCR. Cell proliferation was measured by MTT assay. The expressions of type I collagen, cdc 2, cyclin B1, TIMP-1 and p-ERK proteins were examined by Western blot.

RESULTS

SCAP cells expressed FGFR1 and FGFR2. Exposure of SCAP to bFGF enhanced cell proliferation, and the expression cyclinB1, cdc 2, and TIMP-1, but not type I collagen. U0126 pretreatment and co-incubation attenuated the bFGF-induced proliferation, cdc2, cyclin B1 and TIMP-1 proteins' expression, but not type I collagen in SCAP.

CONCLUSION

SCAP cells express FGFRs. bFGF may stimulate proliferation and affect the matrix turnover of SCAP cells, possibly via stimulation of FGFRs and MEK/ERK signaling pathway. These results are useful for clinical therapies for apexogenesis and regeneration of pulpo-dentin complex.

Basic fibroblast growth factor regulates phosphate/pyrophosphate regulatory genes in stem cells isolated from human exfoliated deciduous teeth

Background

Basic fibroblast growth factor (bFGF) regulates maintenance of stemness and modulation of osteo/odontogenic differentiation and mineralization in stem cells from human exfoliated deciduous teeth (SHEDs). Mineralization in the bones and teeth is in part controlled by pericellular levels of inorganic phosphate (P_i), a component of hydroxyapatite, and inorganic pyrophosphate (PP_i), an inhibitor of mineralization. The progressive ankylosis protein (gene ANKH; protein ANKH) and ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1/ENPP1) increase PP_i and inhibit mineralization, while tissue-nonspecific alkaline phosphatase (ALPL; TNAP) is a critical pro-mineralization enzyme that hydrolyzes PP_i. We hypothesized that regulation by bFGF of mineralization in SHEDs occurs by modulation of P_i/PP_i-associated genes.

Methods

Cells were isolated from human exfoliated deciduous teeth and characterized for mesenchymal stem cell characteristics. Cells were treated with bFGF, and the osteogenic differentiation ability was determined. The mRNA expression was evaluated using real-time polymerase chain reaction. The mineralization was examined using alizarin red S staining.

Results

Cells isolated from primary teeth expressed mesenchymal stem cell markers, CD44, CD90, and CD105, and were able to differentiate into osteo/odontogenic and adipogenic lineages. Addition of 10 ng/ml bFGF to SHEDs during in vitro osteo/odontogenic differentiation decreased ALPL mRNA expression and ALP enzyme activity, increased ANKH mRNA, and decreased both P_i/PP_i ratio and mineral deposition. Effects of bFGF on ALPL and ANKH expression were detected within 24 h. Addition of 20 mM fibroblast growth factor receptor (FGFR) inhibitor SU5402 revealed the necessity of FGFR-mediated signaling, and inclusion of 1 μg/ml cyclohexamide (CHX) implicated the necessity of protein synthesis for effects on ALPL and ANKH. Addition of exogenous 10 μm PP_i inhibited mineralization and increased ANKH, collagen type 1a1 (COL1A1), and osteopontin (SPP1) mRNA, while addition of exogenous P_i increased mineralization and osterix (OSX), ANKH, SPP1, and dentin matrix protein 1 (DMP1) mRNA. The effects of PP_i and P_i on mineralization could be replicated by short-term 3- and 7-day treatments, suggesting signaling effects in addition to physicochemical regulation of mineral deposition.

Conclusion

This study reveals for the first time the effects of bFGF on P_i/PP_i regulators in SHEDs and implicates these factors in how bFGF directs osteo/odontogenic differentiation and mineralization by these cells.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-1093-9) contains supplementary material, which is available to authorized users.

In vitro cell response on CP-Ti surfaces functionalized with TGF-β1 inhibitory peptides

Osseointegration of implants is conversely related to the generation of a fibrous tissue capsule around the implant by the host environment. Although TGF-β1 plays many roles in regeneration processes, it is the cytokine to be mostly associated to the production of fibrotic tissue and thus, its inhibition has demonstrated to be beneficial to prevent several fibrotic reactions. Surface biofunctionalization enables the immobilization of biologically active molecules on an implant surface to tailor the biological response of the host. Here, we studied in vitro biological effects of biofunctionalized CP-Ti surfaces with a TGF-β1 inhibitor peptide, P144. A reliable biofunctionalization process that tethers P144 peptides to commercially pure titanium was developed. Differentiation of human mesenchymal stem cells, osteoblasts and fibroblasts on P144-functionalized and control surfaces was assessed at the gene expression and protein production levels. Results showed that P144-functionalized surfaces reduced expression and production of fibrotic differentiation markers and increased osteoblastic differentiation markers. Therefore, biofunctionalization of surfaces with TGF-β1 inhibitor peptides are an alternative promising strategy for inducing osseointegration around medical devices and implants.

Topical application of bFGF on acid-conditioned and non-conditioned dentin: effect on cell proliferation and gene expression in cells relevant for periodontal regeneration

Periodontal regeneration is still a challenge in terms of predictability and magnitude of effect. In this study we assess the biological effects of combining chemical root conditioning and biological mediators on three relevant cell types for periodontal regeneration.

Association study of candidate genes for susceptibility to Kashin-Beck disease in a Tibetan population

Background

Many osteoarthritis (OA) susceptibility genes have been identified in recent years. Given the overlap in the phenotype of joint inflammation between OA and Kashin-Beck disease (KBD), the aim of this study is to explore whether the reported OA susceptibility genes and two genes that may link to OA pathophysiology are associated with KBD in the Tibetan population.

Method

Fifteen single-nucleotide polymorphisms (SNPs) in 12 candidate genes previously reported as OA susceptibility loci were selected for investigation. Genotyping was performed using the SNaPshot method for these SNPs in a Tibetan population composed of 849 KBD patients and 565 normal controls. Meanwhile, the coding regions of two genes, COL10A1 and HABP2, which may involve in the pathological mechanism of OA/KBD, were sequenced by Sanger sequencing to identify susceptibility coding variants for KBD in the Tibetan population.

Results

The two arthritis-susceptible candidate SNPs, rs7775 (p.Arg324Gly) in the FRZB gene and rs7033979 in the ASPN gene, showed associations with KBD (OR = 1.568, P = 4 × 10⁻³ and OR = 0.744, P = 8 × 10⁻³, respectively). The coding variants rs142463796 (p.Asp128Asn) and rs2228547 (p.Gly545Arg) in the COL10A1 gene (OR = 9.832 and P = 6 × 10⁻³ and OR = 1.242, P = 0.043, respectively) and rs548354451 (p.Asp272Glu) in the HABP2 gene (OR = 2.813, P = 0.010) were associated with KBD patients.

Conclusion

These finding suggested that rs7775 in the FRZB gene may increase susceptibility to KBD, while rs7033979 in the ASPN gene may play a protective role in susceptibility to KBD in Tibetans. Moreover, genetic variants in chondrogenesis-related genes COL10A1 and HABP2 may play a role in the risk of developing KBD in the Tibetan population.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-017-0423-6) contains supplementary material, which is available to authorized users.

Release kinetics and mitogenic capacity of collagen barrier membranes supplemented with secretome of activated platelets - the in vitro response of fibroblasts of the periodontal ligament and the gingiva

Background

Platelet preparations can stimulate the healing process and have mitogenic properties. We hypothesized that collagen barrier membranes (CBM), clinically used in guided bone regeneration and guided tissue regeneration, can serve as carriers for platelet secretome.

Methods

Secretome was generated from washed platelets and unwashed platelets (washed/unwashed PSEC) and lyophilized onto CBM. Overall appearance of CBM was evaluated by scanning electron microscopy. The impact of PSEC on cell attachment was measured based on fluorescence microscopy with DiI-labeled cells. To assess the release kinetics, supernatants of CBM were collected and medium was replaced at hour 1–48. The mitogenic effect was evaluated with periodontal fibroblasts. Furthermore, the release of total protein, platelet-derived growth factor (PDGF)-BB, and transforming growth factor (TGF) β1 was measured.

Results

CBM overall appearance and cell attachment was not modulated by PSEC. Supernatants taken after one hour induced a mitogenic response in fibroblasts and showed the highest levels of total protein, TGFβ1 and PDGF-BB. These effects decreased rapidly in subsequent supernatants. While supernatants of CBM loaded with unwashed PSEC induced a stronger mitogenic response than supernatants of CBM loaded with washed PSEC this difference between the PSEC preparations was not observed when cells were seeded on 48–hours-washed CBM.

Conclusions

CBM release platelet-derived factors in continuously declining release kinetics.

The association of functional polymorphisms in genes encoding growth factors for endothelial cells and smooth muscle cells with the severity of coronary artery disease

Background

Despite the important roles of vascular smooth muscle cells and endothelial cells in atherosclerotic lesion formation, data regarding the associations of functional polymorphisms in the genes encoding growth factors with the severity of coronary artery disease (CAD) are lacking. The aim of the present study is to analyze the relationships between functional polymorphisms in genes encoding basic fibroblast growth factor (bFGF, FGF2), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1), platelet derived growth factor-B (PDGFB), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor A (VEGF-A) and the severity of coronary atherosclerosis in patients with stable CAD undergoing their first coronary angiography.

Methods

In total, 319 patients with stable CAD who underwent their first coronary angiography at the Silesian Centre for Heart Diseases in Zabrze, Poland were included in the analysis. CAD burden was assessed using the Gensini score. The TaqMan method was used for genotyping of selected functional polymorphisms in the FGF2, PDGFB, TGFB1, IGF1 and VEGFA genes, while rs4444903 in the EGF gene was genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The associations between the selected polymorphisms and the Gensini were calculated both for the whole cohort and for a subgroup of patients without previous myocardial infarction (MI).

Results

There were no differences in the distribution of the Gensini score between the genotypes of the analyzed polymorphisms in FGF2, EGF, IGF1, PDFGB, and TGFB1 in the whole cohort and in the subgroup of patients without previous MI. The Gensini score for VEGFA rs699947 single-nucleotide polymorphism (SNP) in patients without previous myocardial infarction, after correction for multiple testing, was highest in patients with the A/A genotype, lower in heterozygotes and lowest in patients with the C/C genotype, (p value for trend = 0.013, false discovery rate (FDR) = 0.02). After adjustment for clinical variables, and correction for multiple comparisons the association between the VEGFA genotype and Gensini score remained only nominally significant (p = 0.04, FDR = 0.19) under the dominant genetic model in patients without previous MI.

Conclusions

We were unable to find strong association between analyzed polymorphisms in growth factors and the severity of coronary artery disease, although there was a trend toward association between rs699947 and the severity of CAD in patients without previous MI.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-016-0402-4) contains supplementary material, which is available to authorized users.

Aminoacyl-tRNA synthetase interacting multi-functional protein 1 attenuates liver fibrosis by inhibiting TGFβ signaling

The aminoacyl-tRNA synthetase interacting multi-functional protein 1 (AIMP1) participates in a variety of cellular processes, including translation, cell proliferation, inflammation and wound healing. Previously, we showed that the N-terminal peptide of AIMP1 (6-46 aa) induced ERK phosphorylation. Liver fibrosis is characterized by excessive deposition of extracellular matrix, which is induced by TGFβ signaling, and activated ERK is known to induce the phosphorylation of SMAD, thereby inhibiting TGFβ signaling. We assessed whether the AIMP1 peptide can inhibit collagen synthesis in hepatic stellate cells (HSCs) by activating ERK. The AIMP1 peptide induced phosphorylation of SMAD2 via ERK activation, and inhibited the nuclear translocation of SMAD, resulting in a reduction of the synthesis of type I collagen. The AIMP1 peptide attenuated liver fibrosis induced by CCl4, in a dose-dependent manner. Masson-Trichrome staining showed that the AIMP1 peptide reduced collagen deposition. Immunohistochemical staining showed that the levels of α-SMA, TGFβ and type I collagen were all reduced by the AIMP1 peptide. Liver toxicity analysis showed that the AIMP1 peptide improved the levels of relevant biological parameters in the blood. These results suggest that AIMP1 peptide may have potential for development as a therapeutic agent to treat liver fibrosis.

Fibroblast growth factor-2 regulates human cardiac myofibroblast-mediated extracellular matrix remodeling

BACKGROUND

Tissue fibrosis and chamber remodeling is a hallmark of the failing heart and the final common pathway for heart failure of diverse etiologies. Sustained elevation of pro-fibrotic cytokine transforming growth factor-beta1 (TGFβ1) induces cardiac myofibroblast-mediated fibrosis and progressive structural tissue remodeling.

OBJECTIVES

We examined the effects of low molecular weight fibroblast growth factor (LMW-FGF-2) on human cardiac myofibroblast-mediated extracellular matrix (ECM) dysregulation and remodeling.

METHODS

Human cardiac biopsies were obtained during open-heart surgery and myofibroblasts were isolated, passaged, and seeded within type I collagen matrices. To induce myofibroblast activation and ECM remodeling, myofibroblast-seeded collagen gels were exposed to TGFβ1. The extent of ECM contraction, myofibroblast activation, ECM dysregulation, and cell apoptosis was determined in the presence of LMW-FGF-2 and compared to its absence. Using a novel floating nylon-grid supported thin collagen gel culture platform system, myofibroblast activation and local ECM remodeling around isolated single cells was imaged using confocal microscopy and quantified by image analysis.

RESULTS

TGFβ1 induced significant myofibroblast activation and ECM dysregulation as evidenced by collagen gel contraction, structural ECM remodeling, collagen synthesis, ECM degradation, and altered TIMP expression. LMW-FGF-2 significantly attenuated TGFβ1 induced myofibroblast-mediated ECM remodeling. These observations were similar using either ventricular or atrial-derived cardiac myofibroblasts. In addition, for the first time using individual cells, LMW-FGF-2 was observed to attenuate cardiac myofibroblast activation and prevent local cell-mediated ECM perturbations.

CONCLUSIONS

LMW-FGF-2 attenuates human cardiac myofibroblast-mediated ECM remodeling and may prevent progressive maladaptive chamber remodeling and tissue fibrosis for patients with diverse structural heart diseases.

The growth factors involved in flexor tendon repair and adhesion formation

Flexor tendon injuries remain a significant clinical problem, owing to the formation of adhesions or tendon rupture. A number of strategies have been tried to improve outcomes, but as yet none are routinely used in clinical practice. Understanding the role that growth factors play in tendon repair should enable a more targeted approach to be developed to improve the results of flexor tendon repair. This review describes the main growth factors in tendon wound healing, and the role they play in both repair and adhesion formation.

Optimization of culture conditions for stem cells derived from human anterior cruciate ligament and bone marrow

Tissue engineering with stem cells is a fascinating approach for treating anterior cruciate ligament (ACL) injuries. In our previous study, stem cells isolated from the human anterior cruciate ligament were shown to possess extensive proliferation and differentiation capabilities when treated with specific growth factors. However, optimal culture conditions and the usefulness of fetal bovine serum (FBS) as a growth factor in in vitro culture systems are yet to be determined. In this study, we compared the effects of different culture media containing combinations of various concentrations of FBS and the growth factors basic fibroblastic growth factor (bFGF) and transforming growth factor-β1 (TGF-β1) on the proliferation and differentiation of ligament-derived stem cells (LSCs) and bone marrow mesenchymal stem cells (BMSCs). We found that α-MEM plus 10% FBS and bFGF was able to maintain both LSCs and BMSCs in a relatively undifferentiated state but with lower major extracellular matrix (ECM) component gene expression and protein production, which is beneficial for stem cell expansion. However, the differentiation and proliferation potentials of LSCs and BMSCs were increased when cultured in MesenPRO, a commercially available stem cell medium containing 2% FBS. MesenPRO in conjunction with TGF-β1 had the greatest ability to induce the differentiation of BMSCs and LSCs to ligament fibroblasts, which was evidenced by the highest ligamentous ECM gene expression and protein production. These results indicate that culture media and growth factors play a very important role in the success of tissue engineering. With α-MEM plus 10% FBS and bFGF, rapid proliferation of stem cells can be achieved. In this study, MesenPRO was able to promote differentiation of both LSCs and BMSCs to ligament fibroblasts. Differentiation was further increased by TGF-β1. With increasing understanding of the effects of different culture media and growth factors, manipulation of stem cells in the desired direction for ligament tissue engineering can be achieved.

Exposure to transforming growth factor-β1 after basic fibroblast growth factor promotes the fibroblastic differentiation of human periodontal ligament stem/progenitor cell lines

Basic fibroblast growth factor (bFGF) is a cytokine that promotes the regeneration of the periodontium, the specialized tissues supporting the teeth. bFGF, does not, however, induce the synthesis of smooth muscle actin alpha 2 (ACTA2), type I collagen (COL1), or COL3, which are principal molecules in periodontal ligament (PDL) tissue, a component of the periodontium. We have suggested the feasibility of using transforming growth factor-β1 (TGFβ1) to induce fibroblastic differentiation of PDL stem/progenitor cells (PDLSCs). Here, we investigated the effect of the subsequent application of TGFβ1 after bFGF (bFGF/TGFβ1) on the differentiation of PDLSCs into fibroblastic cells. We first confirmed the expression of bFGF and TGFβ1 in rat PDL tissue and primary human PDL cells. Receptors for both bFGF and TGFβ1 were expressed in the human PDLSC lines 1-11 and 1-17. Exposure to bFGF for 2 days promoted vascular endothelial growth factor gene and protein expression in both cell lines and down-regulated the expression of ACTA2, COL1, and COL3 mRNA in both cell lines and the gene fibrillin 1 (FBN1) in cell line 1-11 alone. Furthermore, bFGF stimulated cell proliferation of these cell lines and significantly increased the number of cells in phase G2/M in the cell lines. Exposure to TGFβ1 for 2 days induced gene expression of ACTA2 and COL1 in both cell lines and FBN1 in cell line 1-11 alone. BFGF/TGFβ1 treatment significantly up-regulated ACTA2, COL1, and FBN1 expression as compared with the group treated with bFGF alone or the untreated control. This method might thus be useful for accelerating the generation and regeneration of functional periodontium.

Prospective potency of TGF-β1 on maintenance and regeneration of periodontal tissue

Periodontal ligament (PDL) tissue, central in the periodontium, plays crucial roles in sustaining tooth in the bone socket. Irreparable damages of this tissue provoke tooth loss, causing a decreased quality of life. The question arises as to how PDL tissue is maintained or how the lost PDL tissue can be regenerated. Stem cells included in PDL tissue (PDLSCs) are widely accepted to have the potential to maintain or regenerate the periodontium, but PDLSCs are very few in number. In recent studies, undifferentiated clonal human PDL cell lines were developed to elucidate the applicable potentials of PDLSCs for the periodontal regenerative medicine based on cell-based tissue engineering. In addition, it has been suggested that transforming growth factor-beta 1 is an eligible factor for the maintenance and regeneration of PDL tissue.

Genetic study on developmental dysplasia of the hip

BACKGROUND

Developmental dysplasia of the hip (DDH) is a developmental disorder of the hip joint that results in an abnormal socket of the femoral head, ranging from instability, subluxation and complete dislocation of the hip joint. DDH has a considerable genetic component.

DESIGN

We reviewed the recent progress on genetic study of DDH.

RESULTS

By linkage and case-control association studies, DDH loci have been identified with several susceptibility genes that involve in bone and joint biology; however, no unequivocal genes with global significance have been detected. The current problem of the association study in DDH is discussed.

CONCLUSIONS

By advanced technologies and international collaboration, we need to find more susceptibility genes and bridge the gap between genetic evidence and molecular mechanisms.

Cigarette smoke extract induces select matrix metalloproteinases and integrin expression in periodontal ligament fibroblasts

BACKGROUND

The periodontal ligament (PDL) is the connective tissue that anchors the cementum of the teeth to the alveolar bone. PDL fibroblasts are responsible for the production of collagen and remodeling of the PDL. Periodontal disease is increased among smokers in both incidence and severity. This study examines the direct effect of smoking on PDL fibroblasts and their production of various matrix components and remodeling enzymes.

METHODS

PDL cells were plated for 1 day and then treated with various concentrations of cigarette smoke extract (CSE). Survival of PDL cells was quantified after exposure to CSE, and their ability to contract three-dimensional collagen gels was examined. Changes in transcript expression after CSE treatment was compared using reverse transcription-polymerase chain reaction analysis for matrix metalloproteinases (MMPs), collagens, and integrins.

RESULTS

Treatment with CSE-induced cell death at concentrations of ≥5%. PDL-cell-induced collagen gel contraction was reduced at concentrations of 1.5% CSE. Treatment with CSE selectively increased the expression of collagen Vα3 and decreased collagen XIα1. CSE increased the expression of MMP1 and MMP3 and, to a lesser extent, MMP2 and MMP8. CSE also increased the expression of integrins α1, α2, and α10 (collagen receptors) and α9 (a tenascin receptor).

CONCLUSIONS

This study shows that cigarette smoking has local effects on the cells of the PDL. CSE reduced survival of PDL cells and their ability to contract collagen matrices. CSE also altered the expression of molecules known to provide the structural integrity of the ligament by altering collagen synthesis and remodeling as well as cell adhesion.

Growth Differentiation Factor 5 (GDF-5) Induces Matrix Metalloproteinase 2 (MMP-2) Expression in Periodontal Ligament Cells and Modulates MMP-2 and MMP-13 Activity in Osteoblasts

Growth differentiation factor 5 (GDF-5), a member of the transforming growth factor beta (TGF-β) superfamily expressed in periodontal tissues, promotes extracellular matrix (ECM) in periodontal ligament (PDL) cells. Matrix metalloproteinases (MMP) are proteolytic enzymes that degrade ECM and are expressed in PDL cells. To date, little is known about the regulation of MMP synthesis and secretion in PDL cells. The aim of this study is to examine the effects of GDF-5 on MMP production and activity in PDL cells. GDF-5 increased both collagen type I alpha 2 (Col Iα2) and MMP-2 gene expression in cells derived from mouse PDL tissues after 3 days of culture. Because PDL cells represent a heterogeneous population, we examined gelatinolytic activity and gene expression profiles in an osteoblast cell line. After 6, 12, 24, and 48 hours of culture, GDF-5 increased both Col Iα2 and MMP gene expression in osteoblasts. GDF-5 also promoted MMP-2 activity as revealed by gelatin zymography after 7 days of culture. In the presence of the p38 MAP kinase inhibitor SB202190, on the other hand, MMP-2 activity was blocked. Taken together, these results indicate that GDF-5 may increase simultaneously the gene expression of type I collagen and MMP-2 in the osteoblast-like cells among the PDL cells and p38 MAP kinase pathway in osteoblast could involve in the regulation of MMP-2 enzyme activity induced by GDF-5.

Association of the D repeat polymorphism in the ASPN gene with developmental dysplasia of the hip: a case-control study in Han Chinese

Introduction

Developmental dysplasia of the hip (DDH) is a common skeletal disease, which is characterized by abnormal seating of the femoral head in the acetabulum. Genetic factors play a considerable role in the etiology of DDH. Asporin (ASPN) is an ECM protein which can bind to TGF-β1 and sequentially inhibit TGF-β/Smad signaling. A functional aspartic acid (D) repeat polymorphism of ASPN was first described as an osteoarthritis-associated polymorphism. As TGF-β is well known as an important regulator in the development of skeletal components, ASPN may also be involved in the etiology of DDH. Our objective is to evaluate whether the D repeat polymorphism of ASPN is associated with DDH in Han Chinese.

Methods

The D repeat polymorphism was genotyped in 370 DDH patients and 445 control subjects, and the allelic association of the D repeat was examined.

Results

From D11 to D18, eight alleles were identified. D13 allele is the most common allele both in control and DDH groups, the frequencies are 67.3% and 58.1% respectively. In the DDH group, a significantly higher frequency of the D14 allele and significantly lower frequency of D13 was observed. The association of D14 and D13 was found in both females and males after stratification by gender. There was no significant difference in any other alleles we examined.

Conclusions

Our results show an obvious association between the D repeat polymorphism of ASPN and DDH. It indicates that ASPN is an important regulator in the etiology of DDH.

Migration of periodontal ligament fibroblasts on nanometric topographical patterns: influence of filopodia and focal adhesions on contact guidance

Considered to be the "holy grail" of dentistry, regeneration of the periodontal ligament in humans remains a major clinical problem. Removal of bacterial biofilms is commonly achieved using EDTA gels or lasers. One side effect of these treatment regimens is the etching of nanotopographies on the surface of the tooth. However, the response of periodontal ligament fibroblasts to such features has received very little attention. Using laser interference lithography, we fabricated precisely defined topographies with continuous or discontinuous nanogrooves to assess the adhesion, spreading and migration of PDL fibroblasts. PDL fibroblasts adhered to and spread on all tested surfaces, with initial spreading and focal adhesion formation slower on discontinuous nanogrooves. Cells had a significantly smaller planar area on both continuous and discontinuous nanogrooves in comparison with cells on non-patterned controls. At 24 h post seeding, cells on both types of nanogrooves were highly elongated parallel to the groove long axis. Time-lapse video microscopy revealed that PDL fibroblast movement was guided on both types of grooves, but migration velocity was not significantly different from cells cultured on non-patterned controls. Analysis of filopodia formation using time-lapse video microscopy and labeling of vinculin and F-actin revealed that on nanogrooves, filopodia were highly aligned at both ends of the cell, but with increasing time filopodia and membrane protrusions developed at the side of the cell perpendicular to the cell long axis. We conclude that periodontal ligament fibroblasts are sensitive to nanotopographical depths of 85-100 µm, which could be utilized in regeneration of the periodontal ligament.

TGF-ß1 and FAK regulate periostin expression in PDL fibroblasts

Recently identified as a key component of the murine periodontal ligament (PDL), periostin has been implicated in the regulation of collagen fibrillogenesis and fibroblast differentiation. We investigated whether periostin protein is expressed in the human PDL in situ and the mechanisms regulating periostin expression in PDL fibroblasts in vitro. With immunohistochemistry, periostin protein was identified in the PDL, with expression lower in teeth with reduced occlusal loading. In vitro application of uniaxial cyclic strain to PDL fibroblasts elevated periostin mRNA levels, depending on the age of the patient. Treatment with transforming growth factor-beta1 (TGF-β1) also significantly increased periostin mRNA levels, an effect attenuated by focal adhesion kinase (FAK) inhibition. FAK-null fibroblasts contained no detectable periostin mRNA, even after stimulation with cyclic strain. In conclusion, periostin protein is strongly expressed in the human PDL. In vitro, periostin mRNA levels are modulated by cyclic strain as well as TGF-β1 via FAK-dependent pathways.

The effects of exogenous basic fibroblast growth factor on intrasynovial flexor tendon healing in a canine model

BACKGROUND

Studies have demonstrated that flexor tendon repair strength fails to increase in the first three weeks following suturing of the tendon, a finding that correlates closely with the timing of many clinical failures. The application of growth factors holds promise for improving the tendon-repair response and obviating failure in the initial three weeks.

METHODS

The effects of basic fibroblast growth factor on flexor tendon healing were evaluated with use of a canine model. Operative repair followed by the sustained delivery of basic fibroblast growth factor, at two different doses, was compared with operative repair alone. Histological, biochemical, and biomechanical methods were used to evaluate the tendons twenty-one days after repair.

RESULTS

Vascularity, cellularity, and adhesion formation were increased in the tendons that received basic fibroblast growth factor as compared with the tendons that received operative repair alone. DNA concentration was increased in the tendons that received 1000 ng of basic fibroblast growth factor (mean and standard deviation, 5.7 ± 0.7 μg/mg) as compared with the tendons that received 500 ng of basic fibroblast growth factor (3.8 ± 0.7 μg/mg) and the matched control tendons that received operative repair alone (4.5 ± 0.9 μg/mg). Tendons that were treated with basic fibroblast growth factor had a lower ratio of type-I collagen to type-III collagen, indicating increased scar formation compared with that seen in tendons that received operative repair alone (3.0 ± 1.6 in the group that received 500-ng basic fibroblast growth factor compared with 4.3 ± 1.0 in the paired control group that received operative repair alone, and 3.4 ± 0.6 in the group that received 1000-ng basic fibroblast growth factor compared with 4.5 ± 1.9 in the paired control group that received operative repair alone). Consistent with the increases in adhesion formation that were seen in tendons treated with basic fibroblast growth factor, the range of motion was reduced in the group that received the higher dose of basic fibroblast growth factor than it was in the paired control group that received operative repair alone (16.6° ± 9.4° in the group that received 500 ng basic fibroblast growth factor, 13.4° ± 6.1° in the paired control group that received operative repair alone, and 29.2° ± 5.8° in the normal group [i.e., the group of corresponding, uninjured tendons from the contralateral forelimb]; and 15.0° ± 3.8° in the group that received 1000 ng basic fibroblast growth factor, 19.3° ± 5.5° in the paired control group that received operative repair alone, and 29.0° ± 8.8° in the normal group). There were no significant differences in tendon excursion or tensile mechanical properties between the groups that were treated with basic fibroblast growth factor and the groups that received operative repair alone.

CONCLUSIONS

Although basic fibroblast growth factor accelerated the cell-proliferation phase of tendon healing, it also promoted neovascularization and inflammation in the earliest stages following the suturing of the tendon. Despite a substantial biologic response, the administration of basic fibroblast growth factor failed to produce improvements in either the mechanical or functional properties of the repair. Rather, increased cellular activity resulted in peritendinous scar formation and diminished range of motion.

Effects of sevoflurane on collagen production and growth factor expression in rats with an excision wound

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 (PaO(2)) were monitored during the sevoflurane exposure. Collagen type I production and transforming growth factor-beta1 (TGF-beta1) 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 PaO(2). The reduction in wound size and collagen type I production was delayed in S8. The expression of TGF-beta1 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-beta1 and bFGF and subsequently by reduced collagen production.

bFGF and PDGF-BB for tendon repair: controlled release and biologic activity by tendon fibroblasts in vitro

Flexor tendon injuries are often encountered clinically and typically require surgical repair. Return of function after repair is limited due to adhesion formation, which leads to reduced tendon gliding, and due to a lack of repair site strength, which leads to repair site gap formation or rupture. The application of the growth factors basic fibroblastic growth factor (bFGF) and platelet derived growth factor BB (PDGF-BB) has been shown to have the potential to enhance tendon healing. The objectives of this study were to examine: (1) the conditions over which delivery of bFGF can be controlled from a heparin-binding delivery system (HBDS) and (2) the effect of bFGF and PDGF-BB released from this system on tendon fibroblast proliferation and matrix gene expression in vitro over a 10-day interval. Delivery of bFGF was controlled using a HBDS. Fibrin matrices containing the HBDS retained bFGF better than did matrices lacking the delivery system over the 10-day period studied. Delivery of bFGF and PDGF-BB using the HBDS stimulated tendon fibroblast proliferation and promoted changes in the expression of matrix genes related to tendon gliding, strength, and remodeling. Both growth factors may be effective in enhancing tendon healing in vivo.

ABM/P-15 modulates proliferation and mRNA synthesis of growth factors of periodontal ligament cells

OBJECTIVE

Periodontal regeneration is histologically defined as regeneration of the tooth supporting structures, including alveolar bone, periodontal ligament, and cementum. Cells in the remaining periodontal tissues need optimal conditions if they are to perform their functions in the regeneration process. The present study is an investigation of the molecular effects of ABM/P-15 on human periodontal ligament cells (PDL) in vitro.

MATERIAL AND METHODS

PDL cells obtained from healthy subjects were used for in vitro experiments. Cell proliferation, morphology, and mineralization using Von kossa staining were evaluated. mRNA expressions for transforming growth factor-beta (TGF-beta), insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF), bone morphogenic protein-2 (BMP-2), platelet-derived growth factor (PDGF), and type 1 collagen (COL1) were assessed on days 3 and 7 using RT-PCR.

RESULTS

ABM/P-15 enhanced proliferation of cultured PDL cells. It increased the mRNA expression of TGF-beta and BMP-2 in cultured PDL cells on days 3 and 7. IGF-I and b-FGF mRNA expressions showed a slight decrease, while PDGF expression was observed to have increased on day 3. VEGF and COL1 mRNA expressions were found not to be different on days 3 and 7. No differences were observed in the mineralization properties of cultured PDL cells treated with or without ABM/P-15.

CONCLUSIONS

Based on the results of this in vitro study, it may be concluded that ABM/P-15 enhanced the regenerative capacity of PDL by regulating specific gene expressions of cells during early wound healing.

Basic fibroblast growth factor inhibits ventricular remodeling in Dahl salt-sensitive hypertensive rats

OBJECTIVE

Basic fibroblast growth factor (bFGF) inhibits the progression of ventricular remodeling in ischemic and hypertensive heart diseases (HHDs). Recent studies have revealed that bFGF induces the transition from myofibroblasts to fibroblasts with decreased expression of alpha-smooth muscle actin (alpha-SMA). To clarify the mechanisms underlying the reduced ventricular remodeling in hypertensive heart diseases caused by bFGF, we examined the degree of interstitial fibrosis associated with alpha-smooth muscle actin expression and matrix metalloproteinase activity in hypertensive heart diseases.

METHODS

Dahl salt-sensitive rats were fed with a high-salt diet from 6 to 18 weeks of age and injected with a single dose of bFGF (100 microg) into the left myocardium at 15 weeks. Others were administered PBS without bFGF. Control age-matched Dahl salt-sensitive rats were fed with a low-salt diet.

RESULTS

Cardiac systolic function was well preserved and decompensation of heart failure was prevented at 18 weeks in the rats treated with bFGF at 15 weeks. The bFGF-treated rats had significantly fewer interstitial alpha-SMA-positive myofibroblasts and significantly decreased prolyl 4-hydroxylase expression. Increased matrix metalloproteinase-9 gelatinase activity correlated with the downregulation of transforming growth factor-beta1 by bFGF, suggesting that inhibited extracellular matrix deposition is associated with a decreased number of myofibroblasts induced by bFGF.

CONCLUSION

bFGF can inhibit the progression of ventricular remodeling by inhibiting interstitial fibrosis and promoting angiogenesis without decreasing blood pressure in hypertensive heart disease.

Transplantation of basic fibroblast growth factor-pretreated adipose tissue-derived stromal cells enhances regression of liver fibrosis in mice

Adipose tissue-derived stromal cells (ADSC) potentially differentiate into various cell types similar to bone marrow-derived mesenchymal stromal cells (BMSC). Unlike BMSC, ADSC can be harvested easily and repeatedly. However, the advantages of ADSC for cell transplantation in liver disease remain unclear. To investigate this, we developed a novel culture system for ADSC, as well as effective methods for transplantation of ADSC into mice liver. ADSC were isolated from subcutaneous adipose tissues of male C57BL6/J mice and cultured on plastic dishes with or without basic fibroblast growth factor (bFGF). In the in vivo study, ADSC isolated from green fluorescent protein-transgenic mice were transplanted into carbon tetrachloride-injured C57BL6/J mice liver. bFGF-treated ADSC expressed several liver-specific marker genes and demonstrated liver-related functions such as albumin secretion, glycogen synthesis, urea production, and low-density lipoprotein uptake. Importantly, pretreatment of ADSC with bFGF for 1 wk enhanced the repopulation rate of ADSC in mice liver, attenuated liver fibrosis, and restored normal serum alanine aminotransferase and albumin levels. The results indicate that basic FGF facilitates transdifferentiation of ADSC into hepatic lineage cells in vitro and that transplantation of bFGF-pretreated ADSC reduced hepatic fibrosis in mice. ADSC are a potentially valuable source of cells for transplantation therapy.