Proliferation Of Scar Fibroblasts Research Articles

966 Botulinum toxin suppresses pro-fibrotic effects in hypertrophic scar fibroblasts

Hypertrophic scar (HS) is a dermal fibroproliferative disease characterized by the overproduction and deposition of extracellular matrix, cell over-proliferation, enhanced angiogenesis, and enhanced differentiation of fibroblasts to myofibroblasts. Although there has been extensive research on botulinum toxin type A (BTX) treatment for the prevention of HS formation, its effectiveness in the attenuation of skin fibrosis and the related mechanism are unclear. In this study, we investigated the inhibitory effect of BTX on HS-derived fibroblasts (HSFs) in vitro and explored the possible associated molecular mechanism by examining cell proliferation, cell migration, protein expression of scar-related factors, and intracellular signaling. Human scar fibroblasts were cultured and stimulated with BTX. The MTS, scratch, and ELISA, and western blotting were performed to detect changes in fibroblast proliferation, migration, and protein expression of pro-fibrotic factors. Our study revealed that the proliferation, viability and migration of BTX-treated human scar fibroblasts were decreased compared with those of the untreated controls. And protein expression of pro-fibrotic factors including transforming growth factor β1, interleukin-6, and connective tissue growth factor was inhibited by BTX treatment, whereas JNK phosphorylation was activated. Blocking the JNK pathway rescued the inhibitory effects on human scar fibroblast proliferation and the production of pro-fibrotic factors. Therefore it is thought that the suppressive effects of BTX are closely associated with JNK pathway activation. This study showed that BTX has a suppressive effect on extracellular matrix production and scar-related factors in human scar fibroblasts in vitro. Moreover, regulation of JNK signaling played an important role in this process. Our results provide theoretical basis, at the cellular level, for HS treatment.

Pathologic Fibroblasts in Idiopathic Subglottic Stenosis Amplify Local Inflammatory Signals

To characterize the phenotype and function of fibroblasts derived from airway scar in idiopathic subglottic stenosis (iSGS) and to explore scar fibroblast response to interleukin 17A (IL-17A). Basic science. Laboratory. Primary fibroblast cell lines from iSGS subjects, idiopathic pulmonary fibrosis subjects, and normal control airways were utilized for analysis. Protein, molecular, and flow cytometric techniques were applied in vitro to assess the phenotype and functional response of disease fibroblasts to IL-17A. Mechanistically, IL-17A drives iSGS scar fibroblast proliferation ( P < .01), synergizes with transforming growth factor ß1 to promote extracellular matrix production (collagen and fibronectin; P = .04), and directly stimulates scar fibroblasts to produce chemokines (chemokine ligand 2) and cytokines (IL-6 and granulocyte-macrophage colony-stimulating factor) critical to the recruitment and differentiation of myeloid cells ( P < .01). Glucocorticoids abrogated IL-17A-dependent iSGS scar fibroblast production of granulocyte-macrophage colony-stimulating factor ( P = .02). IL-17A directly drives iSGS scar fibroblast proliferation, synergizes with transforming growth factor ß1 to promote extracellular matrix production, and amplifies local inflammatory signaling. Glucocorticoids appear to partially abrogate fibroblast-dependent inflammatory signaling. These results offer mechanistic support for future translational study of clinical reagents for manipulation of the IL-17A pathway in iSGS patients.

LncRNA COL1A2-AS1 inhibits the scar fibroblasts proliferation via regulating miR-21/Smad7 pathway

lncRNA COL1A2-AS1 (COL1A2 antisense RNA 1), a lncRNA overexpressed in hypertrophic scar, has been demonstrated to be involved in the hypertrophic scar formation. However, the mechanisms of lncRNA COL1A2-AS1 inhibiting the scar fibroblasts proliferation remains not well understood. In this study, we demonstrated that lncRNA COL1A2-AS1 was upregulated in hypertrophic scar tissue and fibroblasts, and suppressed fibroblasts proliferation by promoting Smad7 expression. Furthermore, we found that miR-21 was involved in lncRNA COL1A2-AS1-induced expression of Smad7, by which COL1A2-AS1 acted as endogenous sponge to adsorb miR-21 and in turn regulated Smad7 and a cascade of molecular to play a protective role in hypertrophic scar. In addition, overexpression of miR-21 attenuated COL1A2-AS1-mediated proliferation suppression of hypertrophic scar fibroblasts. In conclusion, our study demonstrated that COL1A2-AS1/miR-21/Smad pathway plays an important role in inhibiting hypertrophic scar formation, and suggested this novel pathway may be a new target for hypertrophic scar treatment.

Mast cell chymase promotes hypertrophic scar fibroblast proliferation and collagen synthesis by activating TGF-β1/Smads signaling pathway.

The present study assessed the existence of mast cell chymase in hypertrophic scars and determined whether chymase promotes fibrosis via the transforming growth factor (TGF)-β1/Smads signaling pathway. Five patients with hypertrophic scars and another five patients subjected to repair and reconstruction of other tissue defects were included in the present study. To detect the existence of mast cells and mast cell chymase in hypertrophic scars, immunohistochemistry was employed. To test the effect of chymase on TGF-β1, angiotensin, and type I and III collagen mRNA expression in isolated hypertrophic scar fibroblasts in vitro, reverse-transcription quantitative PCR was performed. To investigate how chymase affects TGF-β1, phosphorylated (P)-Smad2/3 as well as Smad4 and Smad7 protein expression, western blot analysis was used. Mast cell chymase was identified to promote the mRNA expression of TGF-β1, angiotensin, and type I and III collagen in hypertrophic scar fibroblasts in a time- and dose-dependent manner. Furthermore, treatment with 60 ng/ml mast cell chymase for 12 h led to the upregulation of TGF-β1, P-Smad2/3, Smad4 and Smad7 in hypertrophic scar fibroblasts. The present study demonstrated that mast cells and chymase are present in hypertrophic scars, and chymase promotes hypertrophic scar fibroblast proliferation and collagen synthesis by activating the TGF-β1/Smads signaling pathway.

923 The effects of rose bengal on hypertrophic scar fibroblast cell viability and proliferation

923 The effects of rose bengal on hypertrophic scar fibroblast cell viability and proliferation

Expression of mTOR/70S6K signaling pathway in pathological scar fibroblasts and the effects of resveratrol intervention.

The aim of the study was to examine the expression of mammalian target of rapamycin (mTOR)/70S6K signaling pathway in pathological scar fibroblasts and the effects of resveratrol (Res) intervention. The mTOR and 70S6K in pathological scar and normal skin fibroblasts were detected by immunofluorescence following treatment with different concentrations of Res. RT-PCR and western blot analysis were used to detect the expression of mTOR and 70S6K mRNA and protein, respectively. Immunofluorescence showed that the expression of 70S6K and mTOR was significantly enhanced in pathological scar fibroblasts, and mainly expressed in the nucleus, but not in normal skin fibroblasts. RT-PCR and western blot analysis showed that after different concentrations of Res treatments, the mTOR and 70S6K mRNA and protein expression significantly (P<0.05) decreased in a dose-dependent manner. In conclusion, the expression of mTOR/70S6K signaling pathway in pathological scar fibroblasts was significantly enhanced. Res can downregulate the expression of mTOR and 70S6K to achieve the inhibition of pathological scar fibroblast proliferation.

Effects of resveratrol on the expression of molecules related to the mTOR signaling pathway in pathological scar fibroblasts.

We observed the effects of resveratrol on the expression of molecules involved in the mTOR signaling pathway in pathological scar fibroblasts, including PI3K, Akt and mTOR. We detected the expression of PI3K, Akt and mTOR in pathological scar and normal skin fibroblasts through immunofluorescence. After being treated with different concentrations of resveratrol, the expression of PI3K, Akt and mTOR mRNA and protein were detected by RT-PCR and Western Blot respectively. Results showed that the expression of PI3K, Akt and mTOR were significantly enhanced in pathological scar fibroblasts and mainly expressed in the nucleus, with no expression in normal skin fibroblasts. Results from RT-PCR and Western Blot tests demonstrated that after Res intervention with different concentrations for pathological scar fibroblasts, the relative expression quantity of PI3K mRNA and protein decreased and showed a dose dependent relationship. Compared to the control group, the differences were statistically significant (P<0.05). However, decrease in the expression of PI3K mRNA and protein was not obvious and there were no significant differences in comparison to the control group (P>0.05). The mechanism of resveratrol in the inhibition of the proliferation of pathological scar fibroblasts may be related to its down-regulation in the expression of Akt and mTOR, which are the key molecules of mTOR signaling pathway.

Mitomycin C induces apoptosis in human epidural scar fibroblasts after surgical decompression for spinal cord injury.

Numerous studies have shown that topical application of mitomycin C after surgical decompression effectively reduces scar adhesion. However, the underlying mechanisms remain unclear. In this study, we investigated the effect of mitomycin C on the proliferation and apoptosis of human epidural scar fibroblasts. Human epidural scar fibroblasts were treated with various concentrations of mitomycin C (1, 5, 10, 20, 40 μg/mL) for 12, 24 and 48 hours. Mitomycin C suppressed the growth of these cells in a dose- and time-dependent manner. Mitomycin C upregulated the expression levels of Fas, DR4, DR5, cleaved caspase-8/9, Bax, Bim and cleaved caspase-3 proteins, and it downregulated Bcl-2 and Bcl-xL expression. In addition, inhibitors of caspase-8 and caspase-9 (Z-IETD-FMK and Z-LEHD-FMK, respectively) did not fully inhibit mitomycin C-induced apoptosis. Furthermore, mitomycin C induced endoplasmic reticulum stress by increasing the expression of glucose-regulated protein 78, CAAT/enhancer-binding protein homologous protein (CHOP) and caspase-4 in a dose-dependent manner. Salubrinal significantly inhibited the mitomycin C-induced cell viability loss and apoptosis, and these effects were accompanied by a reduction in CHOP expression. Our results support the hypothesis that mitomycin C induces human epidural scar fibroblast apoptosis, at least in part, via the endoplasmic reticulum stress pathway.

Effect of calcium channel blockers on primary cultured human urethra scar fibroblasts

To investigate effects of verapamil on primary cultured human urethral scar fibroblasts (USFs) and to provide basis for protecting the formation of urethra scar. Methods: The cell proliferation was evaluated with the cell counting kit (CCK)-8 method after USFs were incubated various verapamil concentrations (50, 100, 150, 200, or 250 μmol/L) or solvent for 12, 24, or 48 h. The protein level of matrix metalloproteinase (MMP) was evaluated with ELISA after cells were incubated with verapamil (100 μmol/L) or solvent (control cells) for 24 h. Results: The proliferation of USFs was obviously suppressed after verapamil treatment, which was in a dose-dependent and time-dependent manner. Meanwhile, the protein levels of MMP-2 and MMP-9 in the verapamil treatment group increased obviously compared with those of the control groups (P<0.05). Conclusion: Calcium channel blockers may prevent the excessive formation of urethra scar by inhibiting the proliferation of urethral scar fibroblasts and enhancing the activity of MMP.

TGF-β1 promotes scar fibroblasts proliferation and transdifferentiation via up-regulating MicroRNA-21.

TGF-β1, upregulated in keloid tissue, promotes the proliferation, collagen formation and differentiation of dermal fibroblasts. miR-21 is one of microRNAs first found in human genome. The aim of our study is to explore the mechanisms of miR-21 in TGF-β1-induced scar fibroblasts proliferation and transdifferentiation. In the present study, first we found that TGF-β1 promoted scar fibroblasts proliferation and transdifferentiation via up-regulating miR-21 expression, which could be attenuated when miR-21 was inhibited. Overexpression of miR-21 had similar effect as TGF-β1 on proliferation and transdifferentiation. Additionally, TGF-β1 increased the expressions and activities of MMP2 and MMP9 in keloid fibroblasts, which was suppressed by miR-21 inhibition. Finally, the results demonstrated that PTEN/AKT signaling pathway played important role in TGF-β1-induced transdifferentiation. In conclusion, our study suggests that TGF-β1 promotes keloid fibroblasts proliferation and transdifferentiation via up-regulation of miR-21 and PTEN/AKT signalling pathway plays important role in this process, which provides a potential theoretical basis for clinical treatment of skin scars.

Scar Reducing Effect of the Silicone Gel Sheet with Verapamil in a Rabbit Model of Hypertrophic Scar

INTRODUCTION: The CCB verapamil is clinically effective in the treatment of HTSs when injected intralesionally.1,2 We developed a novel treatment based on the topical application of a silicone gel sheet (SGS) containing verapamil microparticles. The ability of these SGSs to inhibit hypertrophic scar (HTS) formation in a rabbit ear wound model was examined. MATERIALS AND METHODS: Ten New Zealand White (NZW) rabbits with a total of 80 wounds in both ears were used in this study. The rabbits were divided into five groups (control, SGS, and SGS+0.25, 2.5, and 25 mg verapamil/g). Histopathologic findings were quantified based on the scar elevation index (SEI) and fibroblast and capillary counts. RESULTS: The mean SEI, fibroblast counts, and capillary counts differed significantly among the five groups (P < 0.05). The median SEI was significantly lower in the SGS+2.5 mg verapamil/g group (Figure 1) than in the SGS group (Figure 2) (1.2 vs. 2.2). The median number of fibroblasts was significantly lower in the SGS+0.25 mg verapamil/g group than in the SGS group (172.5 vs. 243). The median number of capillary lumina was significantly higher in the untreated control group (29.5) whereas there was no significant difference between the SGS group and the SGS+0.25, SGS+2.5, and SGS+25 mg verapamil/g groups (28.5, 18, 20, and 18, respectively).Figure 1: Histopathologic findings of the SGS+0.25 mg verapamil/g group. It has the hypertrophic scar. But scar hypertrophy, fibroblast proliferation and dense connective tissue are less prevalent in this group as compared with the control group and the SGS group (arrow).Figure 2: Histopathologic findings of the SGS group. There are fibroblast proliferation with dense connective tissue, rich capillary lumina and hypertrophic scar (arrow).CONCLUSION: Topical application of SGS with verapamil microparticles may be a novel, effective treatment method for HTS but its safety and efficacy in humans must be tested in clinical trials.

Loureirin B inhibits fibroblast proliferation and extracellular matrix deposition in hypertrophic scar via TGF-β/Smad pathway.

The ethanolic extract of Resina Draconis (RDEE) has been reported beneficial to normal wound healing yielding more regularly arranged collagen fibres. Loureirin B, a major component in RDEE, has been supposed to be effective on the prevention and treatment of pathological scars. To investigate the therapeutic effects of loureirin B on hypertrophic scar (HS), fibroblasts from human HS and normal skin (NS) were isolated. Results showed that loureirin B dose-dependently downregulated both mRNA and protein levels of type I collagen (ColI), type III collagen (ColIII) and α-smooth muscle actin (α-SMA) in HS fibroblasts. Loureirin B also suppressed fibroblast proliferative activity and redistributed cell cycle, but did not affect cell apoptosis. In vivo rabbit ear scar model, loureirin B significantly improved the arrangement and deposition of collagen fibres, decreased protein levels of ColI, ColIII and α-SMA and suppressed myofibroblast differentiation and scar proliferative activity. In NS fibroblasts, loureirin B effectively inhibited TGF-β1-induced upregulation of ColI, ColIII and α-SMA levels, myofibroblast differentiation and the activation of Smad2 and Smad3. Loureirin B also affected mRNA levels of major MMPs and TIMPs in TGF-β1-stimulated fibroblasts. Taken together, this study demonstrates that loureirin B could downregulate the expression of fibrosis-related molecules by regulating MMPs and TIMPs levels, inhibit scar fibroblast proliferation and suppress TGF-β1-induced fibrosis, during which TGF-β1/Smad2/3 pathway is likely involved. These findings suggest that loureirin B is a potential therapeutic compound for HS treatment.

MiR-138/peroxisome proliferator-activated receptor β signaling regulates human hypertrophic scar fibroblast proliferation and movement in vitro.

Excessive scars affect a patient's quality of life, both physically and psychologically, by causing pruritus, pain and contractures. Because there is a poor understanding of the complex mechanisms underlying the processes of hypertrophic scar formation, most therapeutic approaches remain clinically unsatisfactory. In this study, we found that miR-138 was downregulated and peroxisome proliferator-activated receptor (PPARβ) was inversely upregulated in hypertrophic scar tissues compared to in paired normal skin tissues. Using a dual-luciferase assay, we validated that miR138 directly targets PPARβ and regulates its expression at the transcriptional and translational levels. In gain-and-loss experiments, we found that miR-138/PPARβ signaling regulated human hypertrophic scar fibroblast proliferation and movement, and affected scarring-related protein expression, which suggests that miR-138/PPARβ signaling is important for hypertrophic scarring. Thus, our study provides evidence to help determine whether miR-138/PPARβ signaling may be a potential target for hypertrophic scarring management.

Resveratrol Inhibits Proliferation and Induces Apoptosis of Pathological Scar Fibroblasts Through the Mechanism Involving TGF-β1/Smads Signaling Pathway.

The objective of this study was to determine the effect of resveratrol (Res) treatment on pathological scar fibroblasts and the changes in TGF-β1/Smads signaling pathway. For this purpose, cultured pathological scar fibroblasts were treated with various concentrations of Res (10, 50, and, 100 µmol/l), and the morphological changes in target cells were studied using scanning electron microscopy (SEM). The cellular proliferation was assessed by MTT assay; the mRNA and protein expressions of TGF-β1 and Smad-2,3,4,7 were determined by reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescence assay, respectively. We found that Res-treated fibroblasts exhibited the typical apoptotic morphological changes. As shown by MTT assay, the OD values of Res-treated fibroblasts, as a measure of cell growth, were significantly lower than those of controls (P < 0.05). In addition, as compared to controls, TGF-β1 and Smad-2,3,4 mRNA/protein expression decreased but those of Smad7 increased in a dose-dependent manner (P < 0.05). It was, therefore, concluded that Res treatment inhibited the pathological scar fibroblast proliferation and induced cell apoptosis through the mechanism involving downregulation of TGF-β1, Smad-2,3,4, and upregulation of Smad7.

The dose-dependence biological effect of laser fluence on rabbit fibroblasts derived from urethral scar.

Two-micrometer laser vaporization resection has been used in clinic for years, but some patients received the treatment are still faced with excessive and abnormal wound repair which leads to the recurrent of urethral stricture eventually. Fibroblasts play a key role in the processes of "narrow-expansion/operation-restenosis" recurring problems. Here, we investigated the effect of laser fluence biomodulation on urethral scar fibroblasts as well as the underlying mechanism. Urethral scar fibroblasts were isolated and cultured, and laser irradiation (2μm) was applied at different laser fluence or doses (0, 0.125, 0.5, 2, 8, 32J/cm(2)) with a single exposure in 1day. The effect of 2-μm laser irradiation on cell proliferation, viability, and expression of scar formation related genes were investigated. Two-micrometer laser irradiation with intermediate dose (8J/cm(2)) promoted scar fibroblasts proliferation and reactive oxygen species (ROS) production, while higher doses of 32J/cm(2) are suppressive as it decreased the survival rate, viability, and proliferation of fibroblasts. In addition, qRT-PCR and Western blotting results both proven that collagen type I, collagen IV, MMP9, and CTGF display significant increase, yet the TGF-β1 expression was severely reduced at intermediate dose (8J/cm(2)) group when compared with the others groups. Our findings suggest the scar formation-related genes are sensitive to intermediate laser irradiation dose, the most in scar fibroblasts. We revealed the bioeffect and molecular mechanism of 2-μm laser irradiation on rabbit urethral scar fibroblasts. Our study provides new insights into the mechanisms which involved in the excessive and abnormal wound repair of 2-μm laser vaporization resection. These results could potentially contribute to further study on biological effects and application of 2-μm laser irradiation in urethral stricture therapy.

A new, bioactive, antibacterial-eluting, composite graft for infection-free wound healing.

The current work focuses on the in vivo performance of a newly developed injectable composite graft in infected full-thickness wounds. The composite graft was composed of bioactive porous Poly dl-lactide-co-glycolide scaffolds, antibiotic gentamicin, and crosslinked gelatin as carrier gel. Treated infected wounds exhibited a faster wound closure, rapid weight gain, lower neutrophil count, higher breaking strength, and 100 times lesser microbial count (10(2) colony forming units/g in infected treated vs. 10(4) colony forming units/g in infected control group) in comparison with infected control group 28 days post treatment. During healing, collagen production was more in the treated groups at day 7 than controls and thereafter gradually reduced to normal levels. Histology revealed a mature scar tissue formation, fibroblast proliferation, epidermal resurfacing, and collagen deposition in reticular alignment similar to normal healthy skin in treated wounds. Further, the plasma concentration of gentamicin was 35-45 μg/mL during the initial 12 hours and reduced to 1 μg/mL in 24 hours, which indicated safe levels of the antibiotic drug during healing. These results clearly indicate a faster, infection-free, and safe after treatment with the developed graft.

Effect of uighur medicine abnormal savda munzip on human hypertrophic scar fibroblasts in vitro

To evaluate in vitro effect of abnormal savda munziq (ASMq) on the proliferation and apoptosis of human hypertrophic scar fibroblasts (HSFs). HSFs were divided into six groups to receive different treatments as group A (blank control group), group B-E (ASMq in different concentration), and group F(5-Fu). Each group contains six specimens. The HSFs were cultured in vitro. After culture for 48 hours, the CCK8 test and flow cytometry methods were used to detect the proliferation, cell cycle and apoptosis. The proliferation of HSFs in the B, C, D and E groups was inhibited at G2/M period, while it was inhibited at G0/S period in group F (P < 0.05). The inhibition effect of ASMq (0.1-1.0 mg/ml) on the fibroblasts enhanced in a concentration-dependent manner. Flow cytometry analysis with annexin V-FITC and PI staining confirmed the apoptotic. When HSFs were exposed to ASMq at 1.0 mg/ml (group E) for 48 h, the percentage of apoptotic cells increased to (43.7 +/- 2.58)%, which was significantly higher than that of blank control group (2.2 +/- 0.59)%. The induced apoptosis effect was also increased in a concentration-dependent manner. ASMq has a inhibitory effect on the proliferation and an enhancement effect on the apoptosis of fibroblast. ASMq could be used as an effective drug for treatment of hypertrophic scar.

Lapachol suppresses cell proliferation and secretion of interleukin-6 and plasminogen activator inhibitor-1 of fibroblasts derived from hypertrophic scars

The pathogenesis and therapy of hypertrophic scar have not yet been established. Our aim was to investigate the antiproliferative and antisecretory effects of lapachol, isolated from the stem bark of Avicennia rumphiana Hall. f., on hypertrophic scar fibroblasts. The effects of lapachol on hypertrophic scar fibroblast proliferation were measured using the MTT assay, cell-cycle analyses and lactate dehydrogenase assays. The type I collagen α-chain (COL1A1), interleukin-6 (IL-6) and plasminogen activator inhibitor-1 (PAI-1) mRNA and/or protein levels of hypertrophic scar-fibroblasts were quantitated by real-time PCR and ELISA. Lapachol at 25 and 50 µm significantly inhibited the in vitro proliferation of hypertrophic scar fibroblasts, but not fibroblasts from non-lesional skin sites. In addition, lapachol had no apparent effect on cell cycle and lactate dehydrogenase activity in conditioned medium from lapachol-treated hypertrophic scar fibroblasts was nearly equal to that in medium from vehicle-treated cells. Lapachol treatment also inhibited COL1A1 and PAI-1 mRNA levels in hypertrophic scar fibroblasts, but did not affect IL-6 mRNA levels. The protein levels of IL-6 and PAI-1 in conditioned medium from hypertrophic scar fibroblasts treated with 50 µm lapachol were lower than those from vehicle-treated hypertrophic scar fibroblasts. Lapachol decreased the proliferation rate of hypertrophic scar fibroblasts. As IL-6 and PAI-1 secretion was also lowered in lapachol-treated hypertrophic scar fibroblasts, our findings suggested that lapachol may have suppressed extracellular matrix hyperplasia in wound healing and possibly alleviated the formation of hypertrophic scar.

Effects of verapamil and nicardipine on human sear fibroblast in serum-free culture

Objective To study the inhibitory effect of verapamil and nicardipine on human scar fibroblast in serum-free culture and to compare the effectness of the two drugs.Methods We used MTT method to detect the effect of two drugs on human scar fibroblast proliferation:adding verapamil and nicardipine with different concentrations in the culture of fibroblasts which were in logarithmic growth phase (150,100,50,10,0μmol/L).After 24,72,and 120 h,we used MTT method to detect the cell proliferation,and converted the absorbance into growth inhibitory ratio.Results Verapamil and nicardipine showed the definite inhibition on the hypertrophic scar fibroblast (HSFB) and keloid fibroblast (KDFB) which were cultured in vitro.There was some difference in the action feature.In the earlier period,the effect of verapamil was powerful than that of nicardipine.With time,the effect did not reinforce.When fibroblast had been cultured for three to five days,the inhibition became weak.But nicardipine showed lasting inhibition on fibroblast proliferation.Conclusion Combination of verapamil with nicardipine may be a valuable method in the treatment of scar. Key words: Verapamil; Nicardipine; Scar; Fibroblast

Crosstalk between adipose‐derived stem/stromal cells and vocal fold fibroblasts in vitro

To explore adipose-derived stem cell/fibroblast interactions as a potential remodeling pathway for vocal fold scar. Fibroblasts and adipose-derived stem/stromal cells (ASCs) were cultured alone and in combination in a cell-contact-independent paracrine system. Analyses of cell proliferation, and the production of hyaluronic acid (HA) and collagen were performed on samples collected on days 1, 3, and 7. Normal fibroblasts (NFs) were isolated bilaterally from the subepithelial lamina propria of two normal ferret vocal folds. Scar fibroblasts (SFs) were isolated from vocal folds that were electrocauterized 2 weeks before harvest. ASCs were isolated from lipoaspirated subcutaneous abdominal fat of two ferrets. A transwell cell-contact-independent cell communication culturing system was used for coculture experiments. Cells were seeded at 50,000/well in both monoculture and coculture experiments. In monoculture, SFs proliferated faster and produced less HA and more collagen than NFs at day 7 (P < .05). In SF/ASC coculture, SF proliferation was diminished and collagen production at day 7 decreased (P < .05). HA production did not differ between monoculture and coculture conditions. Normal and scar-tissue-derived vocal fold fibroblasts maintain phenotypic differences in culture, thus validating this in vitro scar model. In co-culture, contact-independent crosstalk occurs between SFs and ASCa, leading to less collagen secretion. The data support the hypothesis that ASCs can induce favorable remodeling of scarred vocal folds in vivo by their interactions with endogenous fibroblasts.