Collagen Synthesis In Fibroblasts Research Articles

MiR-590-3p regulates proliferation, migration and collagen synthesis of cardiac fibroblast by targeting ZEB1.

Previous studies have implicated the attractive and promising role of miR‐590‐3p to restore the cardiac function following myocardial infarction (MI). However, the molecular mechanisms for how miR‐590‐3p involves in cardiac fibrosis remain largely unexplored. Using human cardiac fibroblasts (HCFs) as the cellular model, luciferase report assay, mutation, EdU assay and transwell migration assay were applied to investigate the biological effects of miR‐590‐3p on the proliferation, differentiation, migration and collagen synthesis of cardiac fibroblasts. We found that miR‐590‐3p significantly suppressed cell proliferation and migration of HCFs. The mRNA and protein expression levels of α‐SMA, Col1A1 and Col3A were significantly decreased by miR‐590‐3p. Moreover, miR‐590‐3p directly targeted at the 3’UTR of ZEB1 to repress the translation of ZEB1. Interfering with the expression of ZEB1 significantly decreased the cell proliferation, migration activity, mRNA and protein expressions of α‐SMA, Col1A1 and Col3A. Furthermore, the expressions of miR‐590‐3p and ZEB1 were identified in infarct area of MI model in pigs. Collectively, miR‐590‐3p suppresses the cell proliferation, differentiation, migration and collagen synthesis of cardiac fibroblasts by targeting ZEB1. These works will provide useful biological information for future studies on potential roles of miR‐590‐3p as the therapeutic target to recover cardiac function following MI.

Erythroid differentiation regulator 1 (Erdr1) enhances wound healing through collagen synthesis in acne skin.

Acne is a chronic skin disease of the pilosebaceous unit resulting from Propionibacterium acnes (P. acnes), a commensal microorganism. Although numerous therapies are available for acne, there is still a need for the development of effective therapies. Erythroid differentiation regulator 1 (Erdr1) has been suggested to be beneficial during inflammatory skin diseases. In the current study, we first showed that Erdr1 expression level was lower in inflammatory acne skin compared to the normal skin, suggesting that Erdr1 was negatively regulated in acne skin. To evaluate the effect of Erdr1 further, Erdr1 was injected subcutaneously in the acne mouse model. Results revealed that the necrotic lesions by inflamed acne were dramatically decreased and collagen synthesis and fibroblasts activation were induced by Erdr1. In addition, Erdr1 reduced the infiltration of inflammatory cells in vivo and accelerated collagen production in P. acnes-treated human dermal fibroblasts through TGF-β/Smad signaling. Taken together, Erdr1 enhanced wound healing through acceleration of collagen synthesis and activation of fibroblasts in acne skin, suggesting its potential use for acne improvement.

In Vitro Evaluation of Antioxidant, Anti-Inflammatory, Antimicrobial and Wound Healing Potential of Thymus Sipyleus Boiss. Subsp. Rosulans (Borbas) Jalas.

Thymus sipyleus Boiss. subsp. rosulans (Borbas) Jalas (TS) is a commonly used plant in the treatment of various complaints, including skin wounds in Turkish folk medicine. Despite the widespread traditional use of TS, there is not any scientific report confirming the effectiveness of this plant on the healing process. This research aimed to investigate the effects of different extracts obtained from TS on biological events during wound healing, on a cellular basis. In this context, proliferative activities of the extracts, as well as the effects on wound closure and hydroxyproline synthesis, were determined. In addition to wound healing properties, the antioxidant, antibacterial and anti-inflammatory activities of the extracts were evaluated. Decoction (D) and infusion (I) extracts contained the highest amount of phenolic content and showed the most potent activity against DPPH radical. All extracts exhibited complete protection against the damage induced by hydrogen peroxide (H2O2) by increasing cell viability compared to only H2O2-treated groups, both in co-treatment and pre-treatment protocols. None of the extracts exhibited cytotoxic activity, and most of the extracts from the TS stimulated fibroblast proliferation and migration. All TS extracts exert anti-inflammatory activity by suppressing the overproduction of tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO). The most pronounced activity on hydroxyproline synthesis was observed in D extract. In summary, it was observed that TS extracts can promote the healing process by enhancing fibroblast migration, proliferation and collagen synthesis as well as suppressing pro-inflammatory cytokines. The obtained data in this work support the traditional use of TS as a valuable plant-based compound for the treatment of wounds.

MicroRNA-448 overexpression inhibits fibroblast proliferation and collagen synthesis and promotes cell apoptosis via targeting ABCC3 through the JNK signaling pathway.

Idiopathic pulmonary fibrosis (IPF) is a condition that results in the progressive deterioration of lung function with poor prognosis. The current study is aimed at exploring how microRNA-448 (miR-448) targeting ABCC3 affects fibroblast proliferation, apoptosis, and collagen synthesis of mice with IPF via the Jun N-terminal kinase (JNK) signaling pathway. Bioinformatics and dual-luciferase polymerase chain reaction were used to predict the relationship of miR-448 and ABCC3. The expression of miR-448 and ABCC3 was detected in IPF tissues. Using IPF mouse models, lung fibroblasts for the experiments were treated with miR-448 mimic, miR-448 inhibitor, si-ABCC3, or SP600125 (inhibitor of JNK) to evaluate the cell proliferation and apoptosis in response to miR-448. Reverse transcription quantitative polymerase chain reaction and western blot analysis were used to identify the expression of miR-448, ABCC3, and the activation of the JNK signaling pathway. ABCC3 was targeted and downregulated by miR-448 based on bioinformatics prediction and dual-luciferase reporter gene assay. Additionally, miR-448 was found to be highly expressed in IPF lung tissues with low expression levels of ABCC3. In response to the treatment of miR-448 mimic or si-ABCC3, lung fibroblasts exhibited decreased cell proliferation and increased apoptotic rates, whereas the miR-448 inhibitor reversed the conditions. Notably, we also found that miR-448 mimic inhibited the JNK signaling pathway. In conclusion, by using miR-448 to target and downregulate ABCC3 to block the JNK signaling pathway in mice with IPF, we found an increase in fibroblast apoptosis, inhibited cell proliferation, and decreased collagen synthesis of fibroblasts.

Coagulation Factor XIII-A Subunit Missense Mutation in the Pathobiology of Autosomal Dominant Multiple Dermatofibromas

Dermatofibromas are common benign skin lesions, the etiology of which is poorly understood. We identified two unrelated pedigrees in which there was autosomal dominant transmission of multiple dermatofibromas. Whole exome sequencing revealed a rare shared heterozygous missense variant in the F13A1 gene encoding factor XIII subunit A (FXIII-A), a transglutaminase involved in hemostasis, wound healing, tumor growth, and apoptosis. The variant (p.Lys679Met) has an allele frequency of 0.0002 and is predicted to be a damaging mutation. Recombinant human Lys679Met FXIII-A demonstrated reduced fibrin crosslinking activity invitro. Of note, the treatment of fibroblasts with media containing Lys679Met FXIII-A led to enhanced adhesion, proliferation, and type I collagen synthesis. Immunostaining revealed co-localization between FXIII-A and α4β1 integrins, more prominently for Lys679Met FXIII-A than the wild type. In addition, both the α4β1 inhibitors and the mutation of the FXIII-A Isoleucine-Leucine-Aspartate-Threonine (ILDT) motif prevented Lys679Met FXIII-A-dependent proliferation and collagen synthesis of fibroblasts. Our data suggest that the Lys679Met mutation may lead to a conformational change in the FXIII-A protein that enhances α4-integrin binding and provides insight into an unexpected role for FXIII-A in the pathobiology of familial dermatofibroma.

Anti-miR-200b promotes wound healing by regulating fibroblast functions in a novel mouse model.

MicroRNA-200b (miR-200b) down-regulation has been found in wound-healing tissues. Fibroblasts are the predominant cells that orchestrate the production of collagen in wound healing. However, it is still unclear whether miR-200b can affect the wound healing by regulating the fibroblasts' function. The current rodent wound-healing models are not ideal due to their marked difference in structure compared with the human skin. In this study, we demonstrated that the murine plantar skin had similar anatomical features to the human skin. Using this model, the gain/loss-of-function studies showed that miR-200b caused a significantly delayed wound healing in vivo. Furthermore, using cell proliferation, migration and collagen synthesis assays, we found that miR-200b attenuated cell proliferation, migration and collagen synthesis of fibroblasts, which are critical aspects of wound healing. miR-200b also decreased the expression of Zeb1. Collectively, we established a new murine plantar skin model for the investigation of wound healing, and based on it we found that miR-200b affected the wound healing by regulating the biological function of fibroblasts, which provided a new insight for wound healing.

A Potato Peel Extract Stimulates Type I Collagen Synthesis <i>via</i> Akt and ERK Signaling in Normal Human Dermal Fibroblasts

The ability of dermal fibroblasts to synthesize collagen decreases with ages. The integrity of collagen fibers severely decreases in aged skin, causing its characteristic morphological changes such as wrinkles and sagging. To prevent and improve skin aging, the stimulation of collagen synthesis in dermal fibroblasts is important. Potato peels contain many biofunctional compounds, but not much is known about their effects on human skin physiology. To characterize the potential effects of a potato peel extract (PPE) against skin aging, we examined its effects on the synthesis of type I collagen by normal human dermal fibroblasts (NHDFs). Treatment with the PPE significantly increased the expression of type I collagen mRNA in NHDFs and their secretion of type I collagen. To elucidate the mechanism involved, we examined the signaling pathway controlled by transforming growth factor-β (TGF-β), which regulates the synthesis of type I collagen. Treatment of NHDFs with the PPE significantly increased the expression of TGF-β receptor mRNA. TGF-β signaling involves Smad-dependent and Smad-independent pathways, like phosphatidylinositol-3 kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK). The PPE did not activate Smad, but significantly activated Akt and ERK. These results demonstrate that the PPE activates PI3K/Akt and MAPK/ERK signals via TGF-β receptors, which stimulate the synthesis of type I collagen in NHDFs. These results suggest that the PPE could be a novel and effective antiaging material.

628 Activation of the alpha7 nicotinic acetylcholine receptor improves skin fibrosis

Previously we showed an inhibitory effect of tropisetron on transforming growth factor (TGF)-beta1-induced collagen synthesis in human dermal fibroblasts (HDFs) which was alpha7 nicotinic acetylcholine receptors (alpha7nAchR) dependent. In vivo data disclose that tropisetron not only reduced but also prevented experimentally-induced skin fibrosis in the bleomycin (BLM) mouse model of scleroderma. To elucidate the role of the alpha7nAchR in fibrosis, we tested PHA-543613, a full agonist of the alpha7nAchR in the BLM mouse model of scleroderma. A preventive model with simultaneous treatment with BLM and PHA-543613 and a therapeutic model with application of the agonist after induction of fibrosis were used. PHA-543613 treatment resulted in a significant suppression of BLM-induced mRNA expression of murine collagen type I and extracellular matrix genes in mouse skin. Moreover, the α7nAchR agonist dramatically improved fibrosis when added in a therapeutic approach. These results were confirmed at protein level where skin samples injected with PHA-543613 in a preventive as well as therapeutic fashion had significantly lower collagen type I deposition compared to BLM-treated skin. Accordingly, histological analyses disclosed a reduction of dermal thickness after treatment with the alpha7nAchR agonist PHA-543613 in both the preventive and therapeutic approach. These anti-collagen effects could be imitated in vitro where HDFs were treated with the profibrotic factor TGF-beta1 alone and in comparison with PHA-543613 and another full alpha7nAchR agonist AR-R17779. Mechanistically, PHA-543613 and AR-R17779 elicit their anti-TGF-beta1 effect on collagen synthesis via modulation of specific microRNA (miRNAs), such as the profibrotic miR-21 and the antifibrotic miR-29a. In summary the alpha7nAchR agonist PHA-543613 is a novel potent antifibrotic agent, which further underlines the role of the alpha7nAchR in skin fibrosis. Experiments with alpha7nAchR deficient animals lacking this gene are in preparation in our laboratory to further clarify the role of this receptor in fibrosclerotic diseases.

Psoralen attenuates bleomycin-induced pulmonary fibrosis in mice through inhibiting myofibroblast activation and collagen deposition.

Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF inthe inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reducedbody weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM-induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM-induced expression of α-smooth muscle actin atboth the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor-β1, interleukin-1β, and tumor necrosis factor-α in the lungs of BLM-stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM-induced murine model.

Stem Cell–Conditioned Medium Promotes Graft Remodeling of Midsubstance and Intratunnel Incorporation After Anterior Cruciate Ligament Reconstruction in a Rat Model

Background: Stem cell–conditioned medium (CM) has been increasingly used in regenerative medicine. However, its effect on graft-host integration after anterior cruciate ligament (ACL) reconstruction (ACLR) remains unclear. Purpose: To examine the effect of human bone marrow stem cell (hBMSC)–CM on graft-bone integration and graft midsubstance ligamentization in a rat model of ACLR. Study Design: Controlled laboratory study. Methods: CM was obtained from the supernatant of commercially available hBMSCs in serum-free Dulbecco’s modified Eagle medium (DMEM). In a rat model of an ACL injury, isometric ACLR was performed. Three groups were established: CM injection group (CM; n = 40), control injection group (CI; n = 40) with serum-free DMEM injections, and no injection group (NI; n = 40). An intra-articular injection was performed weekly. Micro–computed tomography was conducted at 2, 4, and 8 weeks postoperatively. Histological and biomechanical analyses were conducted at 4 and 8 weeks postoperatively. The NIH3T3 fibroblast was utilized as a model in vitro to examine the effect of CM using the cell counting kit–8 (CCK-8) assay and immunofluorescence staining of Ki-67, α–smooth muscle actin (α-SMA), and collagen 1 (Col 1). Results: At 4 and 8 weeks, the femoral and tibial bone tunnel areas as well as the interface between the graft and host bone were smaller, while the bone volume/total volume ratio was higher, in the CM group. Sharpey-like fibers formed at 8 weeks in the CM group. At 4 and 8 weeks, more Col 1 was noticed in the CM group than in the NI group (both P < .001) or CI group (both P < .001). Immunohistochemically, the α-SMA–positive area was up-regulated at the graft-bone interface at 4 weeks (P < .001) and declined at 8 weeks (P < .001) in the CM group compared with the other 2 groups. At the midsubstance, α-SMA expression decreased from 4 to 8 weeks in all groups and was significantly lower in the CM group than in the NI group (P < .01) or CI group (P < .05) at 8 weeks. The CCK-8 assay showed that CM increased NIH3T3 viability (P < .001) and the level of Ki-67 (P < .05), α-SMA (P < .001), and Col 1 (P < .001) in CM-educated NIH3T3 cells. Conclusion: hBMSC-CM accelerates graft-bone incorporation and midsubstance ligamentization and enhances the proliferation, differentiation, and collagen synthesis of fibroblasts. Clinical Relevance: Graft-host integration is essential after ACLR. The current study identified a novel agent, that is, hBMSC-CM, as a candidate for promoting integration.

Nanofiber scaffolds attenuate collagen synthesis of human dermal fibroblasts through TGF-β1/TSG-6 pathway**No benefit of any kind will be received either directly or indirectly by the authors.

Nanofiber scaffolds are promising patches for skin tissue regeneration as they provide favorable environment for the adhesion, infiltration and proliferation of skin dermal fibroblasts. However, the effects of nanofiber scaffolds on scar formation remain to be elucidated. The aim of this study was to find out the relationship between nanofiber scaffolds and scar formation, along with the underlying mechanism. We found that polycaprolactone (PCL)/gelatin nanofiber scaffolds attenuated the mRNA expression of fibrosis-associated genes in fibroblasts, including collagen I (collagen type I alpha 1), collagen III (collagen type III alpha 1) and fibronectin. Specifically thicker scaffolds displayed stronger fibrosis inhibitory effect than thin scaffolds. The mechanism relied on TGF-β1/TSG-6 pathway, and overexpression of TSG-6 impaired the anti-fibrosis effect of nanofiber scaffolds, which decreased TGF-β1 expression with thickness-dependency. Moreover, in vivo study demonstrated that nanofiber scaffolds remarkably accelerated the wound healing process by reducing the ratios of collagen I/collagen III and TGF-β1, eventually decreased the deposition of collagens. Taken together, our results suggested that the attenuation of fibrosis by PCL/gelatin nanofiber scaffolds was TGF-β1-dependent and through TGF-β1/TSG-6 pathway. Nanofiber scaffold of appropriate thickness would accelerate skin wound healing, stimulate re-epithelialization and form cutaneous skin appendages in skin trauma. Thus, PCL/gelatin nanofiber scaffolds could be adopted for scar-free skin wound healing and skin cosmetics applications.

Promotion of skin fibroblasts collagen synthesis by polydioxanone mats combined with concentrated growth factor extracts

The purpose of this study was to combine polydioxanone and concentrated growth factor extracts to enhance the stimulation of fibroblast collagen synthesis by polydioxanone in facial plastic. In this experiment, polydioxanone was prepared as a nanoscale bioresorbable scaffold by electrospinning. The PDO-CGF mat was prepared by loading the concentrated growth factor extract onto the polydioxanone mat by lyophilization after soaking. The diameter of the mat fibers was observed by scanning electron microscopy, and the mechanical properties, biocompatibility and cytotoxicity of the material were analyzed. The release rate of transforming growth factor-beat1 (TGF-β1) in the PDO-CGF mat was evaluated by enzyme-linked immunosorbent assay (ELISA), and the amount of collagen synthesis was evaluated by real-time polymerase chain reaction (RT-PCR) and immunofluorescence. The results showed that the PDO-CGF mat had a nanometer-scale fiber diameter and an elastic modulus similar to skin and was able to pull during cell contraction. The PDO-CGF mat showed good biocompatibility, and the appropriate concentration of the PDO-CGF mat can significantly promote cell proliferation. ELISA showed that the PDO-CGF mat stably and continuously released TGF-β1. RT-PCR and immunofluorescence staining showed that the PDO-CGF mat stimulated fibroblasts to synthesize type I and type III collagen. These results indicate that a suitable concentration of the PDO-CGF mat can better promote the synthesis of collagen by fibroblasts.

Swainsonine inhibits proliferation and collagen synthesis of NIH-3T3 cells by declining miR-21

Swainsonine (SW) is an indolizidine alkaloid first discovered in Swainsona canescens. This study explored the effects of SW on mouse embryo fibroblast NIH-3T3 cell proliferation and collagen synthesis, as well as potential molecule mechanisms. We discovered that SW exposure lowered the viability and proliferation of NIH-3T3 cells. The collagen synthesis was reduced after SW exposure, as evidenced by declines of the mRNA and protein levels of collagen I (CoI I), collagen III (CoI III) and α-smooth muscle actin (α-SMA) in NIH-3T3 cells, as well as reduction of collagen concentration in the culture supernatant of NIH-3T3 cells. Mechanically, transforming growth factor β1 (TGF-β1) stimulation elevated the microRNA-21 (miR-21) expression in NIH-3T3 cells. SW reversed the TGF-β1-caused elevation of miR-21. Up-regulation of miR-21 attenuated the inhibitory influences of SW on NIH-3T3 cell viability, proliferation and collagen synthesis. Silence of miR-21 had converse influence. Besides, SW inactivated PI3K/AKT and NF-κB pathways via declining miR-21. Altogether, SW inhibited the proliferation and collagen synthesis of fibroblast NIH-3T3 might be through declining miR-21 and then suppressing PI3K/AKT and NF-κB pathways. SW may be an effective therapeutic medicine for scar hyperplasia.

The protective effects of Berberine and Hesperidin on inflammatory factor-stimulating cardiac fibroblasts.

The previous work has shown that Berberine and Hesperidin have beneficial effects on cardiovascular diseases. However, the underlying mechanisms remain unknown. This study aimed to investigate the effect of Berberine and Hesperidin on inflammatory cytokine secretion, proliferation, differentiation, and collagen synthesis of cardiac fibroblasts stimulated by the transforming growth factor-β1 (TGF-β1), and the potential of these drugs to regulate the Notch1 signaling pathway. Neonatal rat primary cardiac fibroblasts were stimulated with 5 ng/mL TGF-β1 as model (TGF) group. In the Berberine (TGF+B) group cells were given TGF-β1, along with 1.25/2.5/5/10 mg/L Berberine, while the Hesperidin (TGF+H) group was treated with TGF-β1 and 12.5/25/50/100 µmmol/L Hesperidin. Cellular proliferation, differentiation, and collagen synthesis were evaluated. The role of the Notch1 signaling pathway in the protective effects of Berberine and Hesperidin was analyzed by using γ-secretase inhibitor (DAPT) to block the Notch1 pathway. 5/10 mg/L Berberine intervention could noticeably decrease both TGF-β1 and IL-1β levels, 25/50/100 µmol/L Hesperidin could reduce IL-1β secretion from TGF-β1 stimulated cardiac fibroblasts. Both Berberine and Hesperidin decreased the expression of α-SMA and cell viability in a concentration-dependent manner; however, the apoptosis of cardiac fibroblasts was not influenced. 10 mg/L Berberine or at least 50 µmol/L Hesperidin could noticeably decrease MMP-1 expression, and at least 5 mg/L Berberine or 100 µmol/L Hesperidin could markedly reduce MMP-9 expression. Using DAPT to block Notch1 signaling could reverse the protective effects of Berberine and Hesperidin. Berberine and Hesperidin can reduce the secretion of inflammatory cytokines, differentiation, and proliferation, and increase the collagen synthesis of cardiac fibroblasts stimulated by TGF-β1 via the Notch1 signaling pathway.

Autophagy mediates 2-methoxyestradiol-inhibited scleroderma collagen synthesis and endothelial-to-mesenchymal transition induced by hypoxia.

To investigate whether autophagy mediates 2-methoxyestradiol (2-ME)-inhibited hypoxia-induced fibrosis and endothelial-to-mesenchymal transition (endoMT) in SSc. Autophagy in the skin of SSc patients was assessed by transmission electron microscopy. SSc skin fibroblasts and human umbilical vein endothelial cells (HUVECs) were cultured under hypoxic (1% O2) conditions with 2-ME or autophagy inhibitor. Collagen I and connective tissue growth factor (CTGF) in fibroblasts and vascular endothelial (VE)-cadherin, CD31, vimentin and α-smooth muscle actin (α-SMA) in HUVECs were examined by western blotting. Autophagic markers were evaluated by confocal microscopy and immunofluorescence. SSc skins presented increased autolysosomes, LC3-II, collagen I and CTGF. Hypoxia-challenged fibroblasts and HUVECs formed more autophagosomes and autolysosomes, with increased LC3 and decreased P62. Meanwhile, hypoxia increased collagen I and CTGF in fibroblasts and increased vimentin and α-SMA but decreased VE-cadherin and CD31 in HUVECs. Bafilomycin A1 increased LC3-II and P62 in fibroblasts and HUVECs and decreased collagen I and CTGF in fibroblasts and vimentin and α-SMA in HUVECs, while upregulating VE-cadherin and CD31. 3-methyladenine decreased autophagy and fibrosis in fibroblasts and endothelial-to-mesenchymal transition in HUVECs. 2-ME-treated HUVECs showed more autophagosomes and fewer autolysosomes while 2-ME-treated fibroblasts showed fewer of both. Moreover, 2-ME decreased LC3-II and increased P62 in fibroblasts and increased both in HUVECs. Inhibition of autophagy by 2-ME showed the same effect with bafilomycin A1 on fibroblast collagen synthesis as well as endothelial and mesenchymal markers in HUVECs. Autophagy mediated hypoxia-induced fibroblast collagen synthesis and endoMT in SSc, which could be reversed by 2-ME.

Anti-fibrotic Effects of Cardiac Progenitor Cells in a 3D-Model of Human Cardiac Fibrosis.

Cardiac fibroblasts play a key role in chronic heart failure. The conversion from cardiac fibroblast to myofibroblast as a result of cardiac injury, will lead to excessive matrix deposition and a perpetuation of pro-fibrotic signaling. Cardiac cell therapy for chronic heart failure may be able to target fibroblast behavior in a paracrine fashion. However, no reliable human fibrotic tissue model exists to evaluate this potential effect of cardiac cell therapy. Using a gelatin methacryloyl hydrogel and human fetal cardiac fibroblasts (hfCF), we created a 3D in vitro model of human cardiac fibrosis. This model was used to study the possibility to modulate cellular fibrotic responses. Our approach demonstrated paracrine inhibitory effects of cardiac progenitor cells (CPC) on both cardiac fibroblast activation and collagen synthesis in vitro and revealed that continuous cross-talk between hfCF and CPC seems to be indispensable for the observed anti-fibrotic effect.

Effect of swim bladder matrix treated with hyaluronic acid on wound healing: an animal model evaluation.

To investigate the potential restorative effects of the white fish (Rutilus frisii kutum) swim bladder matrix (FSBM) treated with hyaluronic acid (HA) in the repair of skin wounds in an animal model. Wistar rats were used to investigate the repair function of FSBM as a biological scaffold. Rats were given four round wounds on their back. Wounds were divided into four groups: control, acellular fish swim bladder matrix (AFSBM), HA and AFSBM impregnated with HA (AFSBM-HA). Macroscopic and histological studies in wound healing were investigated on days three, five and seven after injury. The AFSBM-HA group showed a rapid reduction in wound area compared with the other groups, indicating faster wound healing (p<0.001). At day seven after injury, the AFSBM group showed a faster process in epidermal layer formation and angiogenesis compared with the control group (p<0.001). In the AFSBM-HA group, in addition to the reduction of inflammatory cells density, a significant increase in the number of fibroblast cells and collagen synthesis was observed. An elevation in collagen synthesis and angiogenesis was also observed in the HA group compared with the control group. The findings of this study indicate that AFSBM-HA can potentially be used as a biological dressing in wound healing.

Is leukotriene B4 one of the keloid marker? a fibroblast keloid study

Keloid pathogenesis occurs due to the duration of prolonged inflammatory phase and increased production of various growth factors such as TGF-β1 which may cause increasing fibroblast proliferation and collagen synthesis. Existence of one of the chemical mediators released during inflammation, leukotriene B4 (LTB4), in keloid pathogenesis specifically in the phases of inflammation and proliferation, is still unclear. The purpose of the study is to analyze the levels of LTB4 in keloid. Methods: Fibroblast culture that was done by explanting keloid and normal skin of a keloid patient. Measurement of LTB4 on keloid and normal fibroblast was done by Elisa method. This experiment was run in triplicate. Statistical test was conducted by t test for the unpaired data and Anova test. The experiment was done at cell culture laboratory of Medical Faculty of Padjadjaran University Bandung. Levels of LTB4 in keloid fibroblast was higher than that of normal skin fibroblast (mean 23143.27 vs 18191.85 pg/ml; p&lt;0.05). Conclusion, increased LTB4 levels in keloid fibroblast showed the existence of LTB4 role in the prolonged inflammatory process in keloid pathogenesis.

MicroRNA-155 attenuates profibrotic effects of transforming growth factor-beta on human lung fibroblasts.

Transforming growth factor-beta (TGF-β) functions in fibrogenesis as a profibrotic mediator, regulating cell proliferation, migration, apoptosis and collagen production of fibroblasts. microRNA-155 (miR-155), the expression of which has been related to bleomycin-induced idiopathic pulmonary fibrosis, has been involved in TGF-β induced epithelial-mesenchymal transition. Here, we found that miR-155 expression was decreased in human pulmonary fibroblasts by TGF-β treatment. We overexpressed miR-155 in fibroblasts to investigate the functional impact of miR-155 on TGF-β-induced fibrotic phenotype of fibroblasts. It is suggested that miR-155 overexpression attenuated the stimulatory effect of TGF-β on fibroblast proliferation, migration and collagen synthesis, by evidence from assessment of cell cycle, viability, apoptosis, migration and collagen content. Furthermore, quantitative measurement showed that SMAD1 gene expression was decreased following miR-155 inhibition, thereby demonstrating an indirect miRNA-SMAD interaction that links miR-155 to TGF-β signaling. Our work helped uncover an miRNA-mediated mechanism of fibroblast response to TGF-β. Moreover, it will help to achieve a better understanding of the regulatory roles of miR-155 in fibrogenesis.

Irisin attenuates angiotensin II-induced cardiac fibrosis via Nrf2 mediated inhibition of ROS/ TGFβ1/Smad2/3 signaling axis

Angiotensin II-related cardiac fibrosis is one of the key pathological changes of the hypertrophied left ventricle in various heart disease. Irisin was recently reported to confer cardio-protective and anti-oxidative effects, while whether it can reverse the renin–angiotensin–aldosterone system(RAAS) activation related(angiotensin II-induced) cardiac fibrosis is unknown. In this study, we found that angiotensin II-induced cardiac dysfunction and fibrotic responses were dampened by irisin treatment in mice. Mechanistically, angiotensin II induced robust ROS generation, which in turn triggered activation of pro-fibrotic TGFβ1-Smad2/3 signaling and subsequent collagen synthesis and fibroblast-myofibroblast transformation in cardiac fibroblasts. In contrast, Irisin treatment suppressed angiotensin II-induced ROS generation, TGFβ1 activation, collagen synthesis and fibroblast-myofibroblast transformation, the effects of which was accompanied by Nrf2 activation and also abolished by a Nrf2 targeted siRNA. Taken together, we here identified irisin as a promising anti-fibrotic therapeutic for angiotensin II-related cardiac fibrosis.