OBJECTIVES: To investigate the effect of Haematococcus pluvialis (HP) on bleomycin (BLM)-induced pulmonary fibrosis in mice and on TGF-β1-induced human fetal lung fibroblasts (HFL1). METHODS: Thirty male C57BL/6 mice were randomly divided into control group, BLM-induced pulmonary fibrosis model group, low- and high-dose HP treatment groups (3 and 21 mg/kg, respectively), and 300 mg/kg pirfenidone (positive control) group. The effects of drug treatment for 21 days were assessed by examining respiratory function, lung histopathology, and expression of fibrosis markers in the lung tissues of the mouse models. In TGF-β1-induced HFL1 cell cultures, the effects of treatment with 120, 180 and 240 μg/mL HP or 1.85 μg/mL pirfenidone for 48 h on expression levels of fibrosis markers were evaluated. Transcriptome analysis was carried out using the control cells and cells treated with TGF-β1 and 240 μg/mL HP. RESULTS: HP obviously alleviated BLM-induced lung function damage and fibrotic changes in mice, evidenced by improved respiratory function, lung tissue morphology and structure, inflammatory infiltration, and collagen deposition and reduced expressions of fibrotic proteins. HP at the high dose produced similar effect to PFD. In TGF-β1-induced HFL1 cells, treatment with 240 μg/mL HP significantly reduced the mRNA and protein expression levels of α-SMA and FN. Transcriptome analysis revealed that multiple key genes and pathways mediated the protective effect of HP against pulmonary fibrosis. CONCLUSIONS HP alleviates pulmonary fibrosis in both the mouse model and cell model, possibly as the result of the synergistic effects of its multiple active components.
Animals ; Pulmonary Fibrosis/chemically induced* ; Bleomycin/adverse effects* ; Mice, Inbred C57BL ; Male ; Mice ; Fibroblasts/drug effects* ; Lung/pathology* ; Transforming Growth Factor beta1/pharmacology* ; Myofibroblasts/drug effects* ; Humans ; Pyridones

OBJECTIVE: Silicosis, caused by inhalation of silica dust, is the most serious occupational disease in China and the aim of present study was to explore the protective effect of Ang (1-7) on silicotic fibrosis and myofibroblast differentiation induced by Ang II. METHODS: HOPE-MED 8050 exposure control apparatus was used to establish the rat silicosis model. Pathological changes and collagen deposition of the lung tissue were examined by H.E. and VG staining, respectively. The localizations of ACE2 and α-smooth muscle actin (α-SMA) in the lung were detected by immunohistochemistry. Expression levels of collagen type I, α-SMA, ACE2, and Mas in the lung tissue and fibroblasts were examined by western blot. Levels of ACE2, Ang (1-7), and Ang II in serum were determined by ELISA. Co-localization of ACE2 and α-SMA in fibroblasts was detected by immunofluorescence. RESULTS: Ang (1-7) induced pathological changes and enhanced collagen deposition in vivo. Ang (1-7) decreased the expressions of collagen type I and α-SMA and increased the expressions of ACE2 and Mas in the silicotic rat lung tissue and fibroblasts stimulated by Ang II. Ang (1-7) increased the levels of ACE2 and Ang (1-7) and decreased the level of Ang II in silicotic rat serum. A779 enhanced the protective effect of Ang (1-7) in fibroblasts stimulated by Ang II. CONCLUSION Ang (1-7) exerted protective effect on silicotic fibrosis and myofibroblast differentiation induced by Ang II by regulating ACE2-Ang (1-7)-Mas axis.
Actins ; metabolism ; Angiotensin I ; blood ; pharmacology ; therapeutic use ; Angiotensin II ; blood ; Animals ; Animals, Newborn ; Cell Differentiation ; drug effects ; Cells, Cultured ; Collagen Type I ; metabolism ; Disease Models, Animal ; Lung ; metabolism ; pathology ; Myofibroblasts ; drug effects ; Peptide Fragments ; blood ; pharmacology ; therapeutic use ; Peptidyl-Dipeptidase A ; metabolism ; Rats, Wistar ; Silicosis ; metabolism ; pathology ; prevention & control

BackgroundRecent research indicates that nerve growth factor (NGF) promotes cardiac repair following myocardial infarction by promoting angiogenesis and cardiomyocyte survival. The purpose of this study was to investigate the effects of NGF on cardiac fibroblasts (CFs) proliferation, cell cycle, migration, and myofibroblast transformation in vitro.

MethodsCFs were obtained from ventricles of neonatal Sprague-Dawley rats and incubated with various concentrations of NGF (0, 0.01, 0.1, 1, 10, and 100 ng/ml; 0 ng/ml was designated as the control group). Cell proliferation and cell cycle of the CFs were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry (FCM), respectively. A cell scratch wound model and transwell were carried out to observe effects of NGF on migration of CFs after 24 h of culture. Real-time polymerase chain reaction (RT-PCR) and Western blotting were used to measure α-smooth muscle actin (α-SMA) at mRNA and protein levels after CFs were incubated with various concentrations of NGF.

ResultsExpression of α-SMA measured by RT-PCR and Western blotting significantly increased in the 1 and 10 ng/ml NGF groups (P < 0.05). Absorbance values of CFs showed that NGF did not influence the proliferation of CFs (The Avalues were 0.178 ± 0.038, 0.182 ± 0.011, 0.189 ± 0.005, 0.178 ± 0.010, 0.185 ± 0.025, and 0.177 ± 0.033, respectively, in the 0, 0.01, 0.1, 1, 10, and 100 ng/ml NGF groups [P = 0.800, 0.428, 0.981, 0.596, and 0.913, respectively, compared with control group]), and FCM analysis showed that the percentage of CFs in G0/G1, S, and G2/M phases was not changed (P > 0.05). The cell scratch wound model and transwell showed that CFs migration was not significantly different (P > 0.05).

ConclusionNGF induces myofibroblast transformation but does not influence proliferation, cell cycle, or migration of CFs in vitro.

Actins ; metabolism ; Animals ; Cell Cycle ; drug effects ; physiology ; Cell Movement ; drug effects ; physiology ; Cell Proliferation ; physiology ; Cells, Cultured ; Myofibroblasts ; cytology ; drug effects ; Nerve Growth Factor ; metabolism ; pharmacology ; Rats ; Rats, Sprague-Dawley

Exposure to free silica induces silicosis and myofibroblasts are regarded as primary effector cells. Fibrocytes can differentiate into myofibroblast. Therefore, the present study was designed to investigate whether fibrocytes participate in silicosis. The rat model of silicosis was established. Hematoxylin-eosin stainings and Masson stainings were used to evaluate the histopathology and collagen deposition. Flow cytometry and immunofluorescence were performed to detect the number of fibrocytes and their contribution to myofibroblasts. Results showed that fibrocytes participate in silicosis. Trend analysis of different sources of myofibroblasts during silicosis indicated that fibrocytes and lung type II epithelial cell-derived myofibroblasts play an important role in the early stage of silicosis, while resident lung fibroblast-derived myofibroblasts play a predominant role during the fibrosis formative period.
Animals ; Disease Models, Animal ; Lung ; cytology ; Myofibroblasts ; drug effects ; pathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Silicon Dioxide ; toxicity ; Silicosis ; etiology ; pathology

In the kidney, pericyte is the major source of myofibroblast (MyoF) in renal interstitium. It is reported that pericyte-myofibroblast transition（PMT）is one of the important pathomechanisms of renal interstitial fibrosis（RIF）. Among them, the main reasons for promoting RIF formation include pericyte recruitment, activation and isolation, as well as the lack of pericyte-derived erythropoietin. During the PMT startup process, pericyte activation and its separation from microvessels are controlled by multiple signal transduction pathways, such as transforming growth factor-β（TGF-β）pathway, vascular endothelial growth factor receptor (VEGFR) pathway and platelet derived growth factor receptor (PDGFR) pathway;Blocking of these signaling pathways can not only inhibit PMT, but also suppress renal capillaries reduction and further alleviate RIF. In clinic, many traditional Chinese medicine compound prescriptions, single traditional Chinese herbal medicine (CHM) and their extracts have the clear effects in alleviating RIF, and some of their intervention actions may be related to pericyte and its PMT. Therefore, the studies on PMT and its drug intervention will become the main development direction in the research field of anti-organ fibrosis by CHM.
Drugs, Chinese Herbal ; pharmacology ; Fibrosis ; Humans ; Kidney ; cytology ; drug effects ; pathology ; Myofibroblasts ; cytology ; Pericytes ; cytology ; Receptors, Platelet-Derived Growth Factor ; metabolism ; Signal Transduction ; Vascular Endothelial Growth Factor A ; metabolism

Aortic valve calcification (AVC) is a pathological process correlated with multiple disease causes and actively regulated by cardiac valve cells. In this study, porcine aortic valve myofibroblasts cultured in vitro were treated with 50 μg z L(-1) of pathological factor tumor necrosis factor α (TNF-α). Tanshinone II A (TSN) with the concentration of 50 mg x L(-1) and TNF-α were combined in incubating cells for 72 h (3 d) and 120 h (5 d). The Western blotting and Real-time PCR were adopted to detect the changes in smooth muscle α actin (α-SMA), bone morphogenetic protein 2 ( BMP2), alkaline phosphatase (ALP) in cells, and expressions of key effect proteins GSK-3β and β-catenin on Wnt/β-catenin signal pathway. According to the findings, TNF-α can significantly increase the expression of myofibroblasts α-SMA and add the transformation activity to them, with nearly no expression of BMP2, ALP and mRNA in the control group and the TSN group but significant increase in their expressions in the TNF-α group (P < 0.01), which showed osteoblast-like phenotype. Moreover, TNF-α down-regulated the expression of up-streaming regulator GSK-3β and mRNA expression (P < 0. 01) , notably increased the expression of key effect protein β-catenin, but with no significant difference in mRNA with the control group and the TSN group. The result demonstrated that TSN showed a certain inhibitory effect on TNF-α's pathological impact (P < 0.05) in a time-dependent manner. Inflammatory factor TNF-α may promote the transformation of aortic valvular myofibroblasts to osteoblast-like phenotype by activating Wnt/β-catenin signal pathway in aortic valvular myofibroblasts, so as to cause AVC. Tanshinone II A can have a preventive effect in AVC by activating GSK-3β proteins and regulating signal transduction of Wnt/β-catenin signal pathway.
Animals ; Aortic Valve ; cytology ; drug effects ; metabolism ; Cells, Cultured ; Diterpenes, Abietane ; pharmacology ; Drugs, Chinese Herbal ; pharmacology ; Glycogen Synthase Kinase 3 ; genetics ; metabolism ; Glycogen Synthase Kinase 3 beta ; Myofibroblasts ; cytology ; drug effects ; metabolism ; Osteoblasts ; cytology ; drug effects ; metabolism ; Swine ; Tumor Necrosis Factor-alpha ; genetics ; metabolism ; beta Catenin ; genetics ; metabolism

In order to investigate the roles of Wnt signal pathway in transformation of cardiac valvular myofibroblasts to the osteoblast-like phenotype, the primary cultured porcine aortic valve myofibroblasts were incubated with oxidized low density lipoprotein (ox-LDL, 50 mg/L), and divided into four groups according to the ox-LDL treatment time: control group, ox-LDL 24-h group, ox-LDL 48-h group, and ox-LDL 72-h group. Wnt signal pathway blocker Dickkopf-1 (DDK-1, 100 μg/L) was added in ox-LDL 72-h group. The expression of a-smooth muscle actin (α-SMA), bone morphogenetic protein 2 (BMP2), alkaline phosphatase (ALP), and osteogenic transcription factor Cbfa-1 was detected by Western blotting, and that of β-catenin, a key mediator of Wnt signal pathway by immunocytochemical staining method. The Wnt/β-catenin was observed and the transformation of myofibroblasts to the osteoblast-like phenotype was examined. The expression of α-SMA, BMP2, ALP and Cbfa-1 proteins in the control group was weaker than in the ox-LDL-treated groups. In ox-LDL-treated groups, the protein expression of a-SMA, BMP2, ALP, and Cbfa-1 was significantly increased in a time-dependent manner as compared with the control group, and there was significant difference among the three ox-LDL-treated groups (P<0.05 for all); β-catenin protein was also up-regulated in the ox-LDL-treated groups in a time-dependent manner as compared with the control group (P<0.05), and its transfer from cytoplasm to nucleus and accumulation in the nucleus were increased in the same fashion (P<0.05). After addition of DKK-1, the expression of α-SMA, bone-related proteins and β-catenin protein was significantly reduced as compared with ox-LDL 72-h group (P<0.05). The Wnt/ β-catenin signaling pathway may play an important role in transformation of valvular myofibroblasts to the osteoblast-like phenotype.
Actins ; metabolism ; Animals ; Aortic Valve ; cytology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Gene Expression Regulation ; drug effects ; Intercellular Signaling Peptides and Proteins ; pharmacology ; Lipoproteins, LDL ; pharmacology ; Myofibroblasts ; drug effects ; Osteoblasts ; physiology ; Phenotype ; Swine ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism

α-smooth muscle actin (α-SMA) and tenascin-C are stress-induced phenotypic features of myofibroblasts. The expression levels of these two proteins closely correlate with the extracellular mechanical microenvironment. We investigated how the expression of α-SMA and tenascin-C was altered in the periodontal ligament (PDL) under orthodontic loading to indirectly reveal the intrinsic mechanical microenvironment in the PDL. In this study, we demonstrated the synergistic effects of transforming growth factor-β1 (TGF-β1) and mechanical tensile or compressive stress on myofibroblast differentiation from human periodontal ligament cells (hPDLCs). The hPDLCs under higher tensile or compressive stress significantly increased their levels of α-SMA and tenascin-C compared with those under lower tensile or compressive stress. A similar trend was observed in the tension and compression areas of the PDL under continuous light or heavy orthodontic load in rats. During the time-course analysis of expression, we observed that an increase in α-SMA levels was matched by an increase in tenascin-C levels in the PDL under orthodontic load in vivo. The time-dependent variation of α-SMA and tenascin-C expression in the PDL may indicate the time-dependent variation of intrinsic stress under constant extrinsic loading.
Actins ; analysis ; drug effects ; Adult ; Animals ; Biomechanical Phenomena ; Cell Culture Techniques ; Cell Differentiation ; physiology ; Cells, Cultured ; Cellular Microenvironment ; physiology ; Humans ; Male ; Myofibroblasts ; physiology ; Orthodontic Wires ; Periodontal Ligament ; chemistry ; cytology ; Pressure ; Rats ; Rats, Sprague-Dawley ; Stress, Mechanical ; Tenascin ; analysis ; drug effects ; Time Factors ; Tooth Movement Techniques ; instrumentation ; Transforming Growth Factor beta1 ; pharmacology

OBJECTIVETo explore the inhibition effect and mechanism of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP)on myofibroblast differentiation via regulating acetylated tubulin α (Ac-Tub α)in vivo and in vitro.

METHODSSilicotic model were made by SiO2 douched and divided into 6 groups as follows: control (4w, 8w)group, silicotic model (4w, 8w)group and post-or pre-treatment by Ac-SDKP group. Pulmonary fibroblasts were divided into 5 groups: (1) control; (2) Ang II; (3) Ang II+Ac-SDKP; (4) Ang II+Valsartan; (5) Ang II+TCS histone deacetylase (HDAC)6 20b. The localization of Ac-Tub α and α-smooth muscle actin (SMA) were observed by immunohistochemical (IHC) and immunofluorescence staining. The protein levels of Ac-Tub α, α-SMA, collagen type I (col I) and HDAC6 were measured by western blot.

RESULTSIn silicotic nodules and interstitial fibrosis area, positive expression of α-SMA, a classical marker of myofibroblast, was ob-served by IHC, accompanied with absence expression of Ac-Tub α. Furthermore, Ac-SDKP post-treatment could attenuate the levels of col I, α-SMA and HDAC6 to 48.39%, 52.63% and 70.18% compared with the silicotic 8w group respectively. And in Ac-SDKP pre-treatment group, compared with the silicotic 8w group, these protein levels were decreased to 32.26%, 64.91% and 54.39% respectively (P<0.05). The up-regulation of Ac-Tub α was found in Ac-SDKP post-and pre-treatment and increased to 3.00 and 2.90 folds compared with the silicotic 8w group. Compared with control group, the levels of α-SMA, HDAC6 and col I in Ang II group were up-regulated to 1.66, 3.56 and 4.00 folds accompanied with down-regulation of Ac-Tub by 44.44% (P<0.05). Pre-treatment with Valsartan, TCS HDAC6 20b or Ac-SDKP could inhibited all this changes induced by Ang II in vitro.

CONCLUSIONAc-SDKP can inhibit the myofibroblast differentiation and collagen deposition via sup-press HDAC6 and up-regulate the expression of Ac-Tub α in vivo and in vitro.

Actins ; metabolism ; Animals ; Cell Differentiation ; drug effects ; Collagen Type I ; metabolism ; Disease Models, Animal ; Fibroblasts ; cytology ; Lung ; pathology ; Myofibroblasts ; cytology ; drug effects ; Oligopeptides ; pharmacology ; Rats ; Silicon Dioxide ; toxicity ; Silicosis ; drug therapy ; Tubulin ; metabolism

OBJECTIVETo explore the inhibition effect of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) on myofibroblast differentiation of MRC-5 human fetal lung fibroblasts induced by angiotensin (Ang) II.

METHODSThe study was divided into 2 step: (1) MRC-5 human fetal lung fibroblasts was induced for 48 h at different dose of Ang II and at different time point by 100 nmol/L Ang II. Then the expression of collagen type I and α-smooth muscle actin (α-SMA) were mesaured by western blot. (2) MRC-5 human fetal lung fibroblasts were divided into 4 group: (1) control, (2) Ang II, (3) Ang II+Ac-SDKP, (4) Ang II+8-Me-cAMP (a specific activator of Epac). The α-SMA expression was observed by immnocytochemical stain. The protein expression of collagen type I, α-SMA, serum response factor (SRF), myocardin-related transcription factor (MRTF)-A, exchange protein directly activated by cAMP (Epac) 1, 2 were measured by Westen blot.

RESULTSMyofibroblast differentiation could be induced by Ang II from MRC-5 cells with a dose- and time-dependent manner. The up-regulation of SRF and MRTF-A were observed in MRC-5 cells induced by Ang II and accompanied with collagen I and α-SMA increased. Pre-treatment with 8-Me-cAMP or Ac-SDKP could attenuated all this changes induced by Ang II, and promoted the expression of Epac1.

CONCLUSIONAc-SDKP can inhibit the myofibroblast differentiation of MRC-5 cells induced by Ang II via Epac1 activating.

Actins ; Angiotensin II ; Cell Differentiation ; drug effects ; Collagen ; Collagen Type I ; Cyclic AMP ; analogs & derivatives ; Fetus ; cytology ; Fibroblasts ; cytology ; Guanine Nucleotide Exchange Factors ; Humans ; Lung ; cytology ; Myofibroblasts ; drug effects ; Oligopeptides ; pharmacology ; Serum Response Factor ; Trans-Activators