OBJECTIVETo investigate the potential therapeutic effect of tamoxifen in treating abnormal skin scar contraction.

METHODSFibroblast-populated collagen lattices, which were made by embedding human dermal fibroblasts within type I collagen forming a three-dimensional culture system, were used as an invitro model. Then media either without or with addition of tamoxifen from 1 mumol/L to 50 mumol/L were added to the collagen lattices. Lattice areas were measured at intervals to assess the influence of tamoxifen on the lattice contraction. To visualize changes in the morphology and vitality of fibroblasts, MTT was added to the lattices.

RESULTSTamoxifen had an inhibitory effect on lattice contraction by a dose- and time-dependent pattern. 5 mumol/L or less of tamoxifen didn't show any influence on lattice contraction but 30 mumol/L or higher completely inhibited contraction. At intermediate concentrations from 10 mumol/L to 20 mumol/L the degree of lattice contraction was dose- and time-dependent, which was demonstrated by the reversibility of inhibition. Both the inhibition of contraction and the reversibility of inhibition appeared to correlate with changes in fibroblast morphology.

CONCLUSIONTamoxifen could inhibit the contraction of fibroblast-populated collagen lattices, indicating that tamoxifen may have potential effect on abnormal scar contraction in vivo.

Cicatrix ; drug therapy ; Collagen ; physiology ; Dose-Response Relationship, Drug ; Fibroblasts ; drug effects ; physiology ; Humans ; Skin ; cytology ; drug effects ; Tamoxifen ; pharmacology ; therapeutic use ; Time Factors

BACKGROUNDThrombin is a multifunctional serine protease that plays a crucial role in hemostasis following tissue injury. In addition to its procoagulation effect, thrombin is also a potent mesenchymal cell mitogen, therefore it plays important roles in the local proliferation of mesenchymal cells in the tissue repair process. Reactive oxygen species (ROS) can induce some human cells to proliferate at lower rates while at higher concentrations they promote cells to undergo apoptosis or necrosis. Accumulative evidence suggests that thrombin can induce some cells to produce ROS. Based on these observations, we provide a hypothesis that thrombin can stimulate human lung fibroblasts to produce ROS, which play an important role in human lung fibroblast proliferation.

METHODSROS were detected in fibroblasts at 30 minutes and 60 minutes following thrombin (20 U/ml) exposure using flow cytometry. The ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) was assayed in lung fibroblasts using a commercial kit following treatment with thrombin at different concentrations. NADPH oxidase and the extracellular regulated kinase1/2 (ERK1/2) signaling pathway were detected by Western blotting after thrombin stimulation to lung fibroblasts.

RESULTSThrombin, at 20 U/ml, stimulated human lung fibroblasts (HLF) to generate ROS in a time dependent manner. The ratio of GSH/GSSG in fibroblasts treated with thrombin showed a significant decrease. NADPH oxidase was activated and the ERK1/2 signal pathway was involved in the proliferation process of fibroblasts treated with thrombin.

CONCLUSIONThe activation of NADPH oxidase by thrombin leads to the production of ROS, which promotes fibroblasts proliferation via activation of the ERK1/2 signaling pathway.

Cell Proliferation ; drug effects ; Cells, Cultured ; Extracellular Signal-Regulated MAP Kinases ; analysis ; physiology ; Fibroblasts ; drug effects ; physiology ; Flow Cytometry ; Glutathione ; metabolism ; Humans ; Lung ; cytology ; NADPH Oxidases ; analysis ; physiology ; Reactive Oxygen Species ; metabolism ; Signal Transduction ; physiology ; Thrombin ; pharmacology

An extracellular matrix protein plays an important role in skin wound healing. In the present study, we engineered a recombinant protein encompassing the 9th and 10th type III domains of fibronectin, and 4th FAS1 domain of beta ig-h3. This recombinant protein, in total, harbors four known-cell adhesion motifs for integrins: Pro-His-Ser-Arg-Asn (PHSRN) and Arg-Gly-Asp (RGD) in 9th and 10th type III domains of fibronectin, respectively, and Glu-Pro-Asp-Ile-Met (EPDIM) and Try-His (YH) in 4th FAS1 domain of big-h3, were designated to tetra-cell adhesion motifs (T-CAM). In vitro studies showed T-CAM supporting adhesion, migration and proliferation of different cell types including keratinocytes and fibroblasts. In an animal model of full-thickness skin wound, T-CAM exhibited excellent wound healing effects, superior to both 4th FAS1 domain of beta ig-h3 or 9th and 10th type III domains of fibronectin. Based on these results, T-CAM can be applied where enhancement of cell adhesion, migration and proliferation are desired, and it could be developed into novel wound healing drug.
Amino Acid Motifs ; Animals ; Cell Adhesion/*drug effects ; Cell Line ; Cell Movement/*drug effects ; Cell Proliferation/*drug effects ; Extracellular Matrix Proteins/chemistry/genetics/pharmacology ; Fibroblasts/cytology/drug effects/physiology ; Fibronectins/chemistry/genetics/*pharmacology ; Humans ; Keratinocytes/cytology/drug effects/physiology ; Mice ; NIH 3T3 Cells ; Rabbits ; Recombinant Fusion Proteins/chemistry/genetics/pharmacology ; Transforming Growth Factor beta/chemistry/genetics/pharmacology ; Wound Healing/*drug effects/physiology

To explore the influence of calculus bovis on the function of primary cultured mice oral fibroblasts, we determined the effects of calculus bovis on the fibroblast proliferation, collagen production, matrix metalloproteinases-2, -9 activities and tissue inhibitor of metalloproteinase-1 production by MTT assay, chloramine T method, gelatin zymography and enzyme-linked immunosorbent assays respectively. The results showed that calculus bovis could significantly inhibit the proliferation of fibroblasts and collagen synthesis in a concentration dependent manner, could significantly (P<0.05) suppress matrix metalloproteinases-2 activity and very significantly (P<0.01) inhibit the production of tissue inhibitor of metalloproteinase-1. In conclusion, the major function of calculus bovis in the process of ulcer healing is not to promote tissue regeneration, the mechanism that calculus bovis inhibits collagen synthesis may be partly due to its ability to very significantly (P<0.01) suppress the production of tissue inhibitor of metalloproteinase-1.
Animals ; Cattle ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cholelithiasis ; chemistry ; veterinary ; Collagen ; drug effects ; metabolism ; Fibroblasts ; cytology ; physiology ; Materia Medica ; pharmacology ; Mice ; Mice, Inbred BALB C ; Mouth Mucosa ; cytology ; Tissue Inhibitor of Metalloproteinase-1 ; drug effects ; metabolism

OBJECTIVETo study the role of cycline dependent kinase 4 (CDK4) in the malignant transformation of human fetal lung diploid fibroblast cell (2BS) induced by silica.

METHODSRecombination vectors with antisense pXJ41-CDK4 were constructed, and then were transfected into the malignant transformed cells induced by silica. In situ hybridization and immunohistochemistry were used to analyze the expression of CDK4. Cell growth curve, doubling time, cell cycle distribution and the growth capacities on soft agar were analyzed before and after antisense CDK4 RNA was transferred into malignant transformed cells induced by silica.

RESULTSDuring the malignant transformation of 2BS cells induced by silica, CDK4 gene was overexpressed. Antisense pXJ41-CDK4 transduction suppressed CDK4 gene expression in the antisense pXJ41-CDK4 transfected cells. Antisense CDK4 RNA led to cell cycle arrest, resulting in lengthened G1 phase (the percentages of cells in the G1 phase increased from 45.1% to 58.0%), and eventually attenuated the proliferation of malignant transformed cells induced by silica. At the 8th day, the suppression rates decreased by 77.43%. The doubling time prolonged from 21.0 h to 42.7 h. The growth capacities on soft agar of cells transfected by antisense pXJ41-CDK4 were decreased.

CONCLUSIONCDK4 might play an important role in maintaining the transformed phenotype of the cancer cells.

Cell Transformation, Neoplastic ; drug effects ; Cells, Cultured ; Cyclin-Dependent Kinase 4 ; Cyclin-Dependent Kinases ; genetics ; physiology ; Embryo, Mammalian ; Fibroblasts ; cytology ; drug effects ; Humans ; Lung ; cytology ; Proto-Oncogene Proteins ; genetics ; physiology ; RNA, Antisense ; pharmacology ; RNA, Messenger ; genetics ; Silicon Dioxide ; toxicity

OBJECTIVELipoxin A(4) is formed by the metabolism of arachidonic acid. Anti-inflammatory and anti-proliferative effect of lipoxin A(4) has been shown in many human diseases. Recently, as a novel high affinity receptor for ligand lipoxin A(4), Lipoxin A(4) receptor-like protein (LRLP) has been identified. Currently close attention is paid to the important contribution of connective tissue growth factor (CTGF) in lung fibrosis. The purpose of the study was to transfect LRLP gene into human lung fibroblasts and investigate the mechanism of its enhancing antagonistic effect of Lipoxin A(4) on human lung fibroblasts proliferation induced by connective tissue growth factor.

METHODSEukaryocytic expression vector pEGFP/LRLP which contained LRLP and green fluorescence protein fusion gene (GFP) was constructed and transfected into human lung fibroblasts (HLF). After selecting with G418, HLF/LRLP cell clone which stably expressed LRLP/GFP fusion protein was isolated and characterized by the laser scanning confocal microscope. Cultured HLF and HLF/LRLP were stimulated for 24 h with CTGF (1 microg/ml) in the presence and absence of pretreatment of Lipoxin A(4) (10.0 nmol/L) for 30 min. Inhibition of cell proliferation was determined by MTT assay. Cell cycle analysis was performed by flow cytometry. Western blot was used to detect the expression of cyclin D(1) protein. Electrophoretic mobility shift assay (EMSA) was employed to detect the DNA binding activity of STAT(3).

RESULTS(1) HLF/LRLP cell clone which stably expressed LRLP and GFP fusion protein was successfully obtained. (2) Proliferation of HLF and HLF/LRLP was induced by 1 microg/ml CTGF. Pretreatment with 10 nm Lipoxin A(4) inhibited the proliferation of HLF and HLF/LRLP. And the inhibitory rate of HLF/LRLP was significantly higher than that of HLF [(54.1 +/- 4.2)%, (21.2 +/- 3.7)%, P < 0.05]. (3) The flow cytometry analysis showed that compared with HLF, more HLF/LRLP were arrested at G(0)/G(1) phase in the presence of pretreatment of Lipoxin A(4). [(76.3 +/- 3.5)%, (60.8 +/- 2.0)%, P < 0.05]. (4) Ten nmol/L Lipoxin A(4) antagonized CTGF induced increase of cyclin D(1) protein expression in HLF and HLF/LRLP. And its antagonistic effect on HLR/LRLP was stronger than that on HLF (P < 0.05). (5) Ten nmol/L Lipoxin A(4) antagonized CTGF induced increase of STAT(3) DNA binding activity, and its antagonistic effect on HLF/LRLP was more powerful than that on HLF (P < 0.05).

CONCLUSIONSTransfection of Lipoxin A(4) receptor-like protein gene enhanced the inhibitory effect of Lipoxin A(4) on human lung fibroblasts proliferation induced by CTGF. Its mechanism might be related to regulation of cyclin D(1) protein expression and STAT(3) DNA binding activity.

Connective Tissue Growth Factor ; antagonists & inhibitors ; Cyclin D1 ; analysis ; DNA ; metabolism ; Fibroblasts ; cytology ; drug effects ; Humans ; Lipoxins ; pharmacology ; Lung ; cytology ; drug effects ; Receptors, Formyl Peptide ; genetics ; physiology ; Receptors, Lipoxin ; genetics ; physiology ; STAT3 Transcription Factor ; metabolism ; Transfection

OBJECTIVETo investigate the role of calcineurin (CaN) in the lung fibroblast proliferation and collagen synthesis induced by basic fibroblast growth factor (bFGF).

METHODSWe used Western blot and immunohistochemical methods for investigating the content and distribution of calcineurin in the lung tissue. Calcineurin activity in different tissues was measured using (32)P-labelled substrate. In the primary culture of lung fibroblasts, (3)H-thymidine ((3)H-TdR) and (3)H-proline incorporation methods were used to study the effect of cyclosporin A (CsA), an inhibitor of calcineurin, on the lung fibroblast DNA and collagen synthesis stimulated by bFGF.

RESULTSWe found that calcineurin was expressed in lung tissue and has phosphatase activity (7.1 +/- 2.0 pmol Pi/mg pr/min). CsA (10(-8) - 10(-6) mol/L) inhibited lung fibroblast (3)H-TdR incorporation induced by bFGF in a dose-dependent manner, with the inhibitory rates by 20%, 46% and 66% (P < 0.01). CsA (10(-7) - 10(-6) mol/L) inhibited (3)H-proline incorporation in lung fibroblasts stimulated by bFGF, with the inhibitory rates by 21% and 37% (P < 0.01). In a culture medium, CsA (10(-8) - 10(-6) mol/L) inhibited (3)H-proline secretion induced by bFGF in a dose-dependent manner, with the inhibitory rates by 19%, 29% (P < 0.05) and 56% (P < 0.01). CsA (10(-7) mol/L) could inhibit calcineurin activity by 44% in lung fibroblasts (P < 0.01).

CONCLUSIONSCalcineurin is expressed in lung tissue and has phosphatase activity. It is involved in the bFGF stimulated lung fibroblast DNA and collagen synthesis.

Animals ; Calcineurin ; analysis ; physiology ; Cell Division ; Cell Survival ; drug effects ; Collagen ; biosynthesis ; Fibroblast Growth Factor 2 ; pharmacology ; Fibroblasts ; drug effects ; physiology ; Lung ; cytology ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley

This study was aimed to investigate the effects of human bone marrow fibroblastoid stromal cell line (HFCL) on chemosensitivity of acute myeloid leukemia sensitive HL-60 cell line and multidrug-resistant (MDR) HL-60/VCR cell line in vitro co-culture. Setting up co-culture system of HL-60 or HL-60/VCR cells in direct contact with HFCL cells, or with HFCL cells separated by transwell, and exposing HL-60 or HL-60/VCR cells to different concentrations of topotecon (TPT), morphologic evidence for apoptosis was determined by staining with Wright-Giemsa stain and acridine orange/ethidium bromide (AO/EB). Cell cycle, sub-G(1) and annexin V FITC staining were detected by flow cytometry. The expression of active caspase-3, Bcl-2 and Pgp was detected by Western blot. The results showed that HL-60 or HL-60/VCR cells treated by TPT revealed characteristic apoptotic morphological changes by Wright-Giemsa and AO/EB staining. The percentage of annexin V-positive cells and apoptotic cells decreased when they were cocultured with HFCL cells. The proportion of G(0)/G(1) HL-60 or HL-60/VCR cells treated by TPT increased and the sub-G(1) appeared significantly, but apoptotic and sub-G cells reduced after direct contact with HFCL cells. Meanwhile, although HL-60 or HL-60/VCR cells treated by TPT expressed activated caspase-3, and the expression of Bcl-2 decreased, the expression of activated caspase-3 decreased and Bcl-2 increased after direct contact with HFCL cells. In conclusion, HFCL stromal cells can prevent TPT-induced apoptosis in HL-60 and HL-60/VCR cells via modulation of Bcl-2 and active caspase-3.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; physiology ; Blotting, Western ; Bone Marrow Cells ; cytology ; physiology ; Caspase 3 ; metabolism ; Cell Cycle ; drug effects ; physiology ; Cell Line ; Coculture Techniques ; Dose-Response Relationship, Drug ; Drug Resistance, Neoplasm ; Fibroblasts ; cytology ; physiology ; Flow Cytometry ; HL-60 Cells ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Stromal Cells ; cytology ; physiology ; Topotecan ; pharmacology ; Vincristine ; pharmacology

OBJECTIVETo observe the effects of Bushen Qianggu decoction proliferation and PCNA and Bcl-2 expression.

METHODSSerum containing BQD was made and synovial fibroblasts were separated and cultured and passaged in vitro. Four groups were divided as 20% blank control group, serum containing 20% Tripterygium wilfordii multi-glycosides drug (TWMD), 20% of serum containing high and low of BQD, respectively. Serum containing drugs of different concentration were added into the synovial fibroblasts of the third generation, and then the synovial fibroblasts were cultured continued. The effects of different drugs on synovial fibroblasts and PCNA and Bcl-2 expression were observed.

RESULTSCompared with the control serum, BQD-containing serum promoted the apoptosis of synovial fibroblasts (P < 0.000 1); especially, high dose could inhibit proliferation. The expression of PCNA and Bcl-2 was significantly lower in BQD-containing serum (P < 0.000 1 vs control group).

CONCLUSIONBQD can promote the apoptosis of synovial fibroblasts by improving of expression of PCNA and Bcl-2, which may be one of the mechanisms of BQD in preventing and treating osteoporosis of rheumatoid arthritis.

Animals ; Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Female ; Fibroblasts ; drug effects ; physiology ; Proliferating Cell Nuclear Antigen ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rats ; Rats, Wistar ; Synovial Membrane ; chemistry ; cytology ; drug effects

OBJECTIVETo study the molecular mechanism of the inhibitory effects of vitamin C on benzo[a]pyrene (B[a]P)-induced changes of cell cycle in human embryo lung fibroblast (HELF) cells.

METHODSThe stable transfectants, HELF transfected with antisense cyclin D1 and antisense CDK4, were established. Cells were cultured and pretreated with vitamin C before stimulation with B[a]P for 24 h. The expression levels of cyclin D1, CDK4, E2F1, and E2F4 were determined by Western blot. Flow cytometric analysis was employed to detect the distributions of cell cycle.

RESULTSB[a]P significantly elevated the expression levels of cyclin D1, E2F1, and E2F4 in HELF cells. Vitamin C decreased the expression levels of cyclin D1, E2F1, and E2F4 in B[a]P-stimulated HELF cells. Dose-dependent relationships were not found between the different concentrations of vitamin C (10, 100, 500, 1000, and 5000 micromol/L) and the expression levels of cyclin D1, E2F1, and E2F4 in HELF cells. The expression levels of cyclin D1, E2F1, and E2F4 in B[a]P-treated transfectants were lower than those in B[a]P-treated HELF cells. The expression levels of cyclin D1 and E2F4 treated with vitamin C and antisense cyclin D1 were decreased compared with those treated with antisense cyclin D1 alone. The effects of vitamin C combined with antisense CDK4 on the expression levels of cyclin D1 and E2F1/E2F4 were similar to those of antisense CDK4 alone. B[a]P progressed HELF cells from G1 to S phase. Both vitamin C and antisense cyclin D1 suppressed the changes of cell cycle progressed by B[a]P. However, antisense CDK4 did not attenuate the above changes. Vitamin C combined with antisense CDK4 markedly suppressed B[a]P-induced changes of cell cycle as compared with antisense CDK4. But the inhibitory effects of vitamin C combined with antisense cyclin D1 on B[a]P-induced changes of cell cycle were similar to those of vitamin C alone or antisense cyclin D1 alone.

CONCLUSIONSB[a]P progressed HELF cells from G1 to S phase via intracellular signaling pathway of cyclin D1/E2F. Vitamin C may modulate this signaling pathway to protect cells from injury caused by B[a]P.

Ascorbic Acid ; pharmacology ; Benzo(a)pyrene ; Blotting, Western ; methods ; Cell Cycle ; drug effects ; physiology ; Cells, Cultured ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Dose-Response Relationship, Drug ; E2F1 Transcription Factor ; metabolism ; Fibroblasts ; cytology ; drug effects ; metabolism ; G1 Phase ; drug effects ; physiology ; Humans ; Lung ; cytology ; embryology ; RNA, Antisense ; genetics ; S Phase ; drug effects ; physiology ; Transfection ; methods