transforming-growth-factor-beta and Carotid-Stenosis

Topics: Angioplasty, Balloon; Animals; Arteriosclerosis; Carotid Stenosis; Endopeptidases; Endothelium, Vascular; Fibroblast Growth Factors; Gene Expression Regulation; Humans; Models, Biological; Muscle, Smooth, Vascular; Nitric Oxide; Platelet-Derived Growth Factor; Proliferating Cell Nuclear Antigen; Rats; Receptors, Platelet-Derived Growth Factor; Recurrence; Renin-Angiotensin System; Swine; Transforming Growth Factor beta; Wound Healing

The aim of this study was to evaluate CD25

Topics: Aged; Aged, 80 and over; Antigens, CD; Aortic Dissection; Carotid Stenosis; Case-Control Studies; Female; Humans; Interleukin-10; Interleukin-2 Receptor alpha Subunit; Interleukin-6; Lymphocyte Activation Gene 3 Protein; Male; Middle Aged; T-Lymphocytes, Regulatory; Transforming Growth Factor beta

Carotid atherosclerotic plaque is one of the main sources of ischemic stroke, and endothelial-to-mesenchymal transition (EndMT) is a major feature of atherosclerosis. Rho-associated coiled-coil-containing protein kinase 1 (ROCK1) activation, stimulated by high glucose, plays an important role in EndMT, and circadian locomotor output cycles protein kaput (Clock) deficiency leads to hyperglycemia and enhanced atherosclerosis in Clock. Cultured human umbilical vein endothelial cells (HUVECs) were stimulated with 66 mM glucose for 120 h to induce EndMT. The expression of CLOCK and ROCK1 was assayed, as were their effects on EndMT. We also conducted molecular and morphometric examination of carotid artery plaques from patients with carotid artery stenosis to assess the clinical relevance of these findings.. Upon EndMT, HUVECs exhibited decreased CLOCK expression and increased ROCK1 expression. Notably, CLOCK silencing increased high glucose-induced EndMT, migration ability, and ROCK1 activation, while overexpressing CLOCK attenuated these characteristics. Moreover, inhibition of ROCK1 largely blocked EndMT induced by high-glucose or transforming growth factor (TGF)-β1 but failed to rescue the reduced CLOCK expression. The vulnerability of human carotid artery plaque was strongly correlated with loss of CLOCK expression, activation of TGF-β/ROCK1 signaling, and the extent of EndMT.. The data indicate that loss of protective endothelial CLOCK expression aggravates TGF-β/ROCK1-modulated EndMT progression, which contributes to the vulnerability of human carotid plaque.

Topics: Carotid Stenosis; Cell Movement; Cell Shape; Cells, Cultured; CLOCK Proteins; Down-Regulation; Epithelial-Mesenchymal Transition; Glucose; Human Umbilical Vein Endothelial Cells; Humans; Plaque, Atherosclerotic; rho-Associated Kinases; Rupture, Spontaneous; Signal Transduction; Transforming Growth Factor beta; Up-Regulation

Over the last few years the role of microorganisms in the pathogenesis of atherosclerosis has been widely discussed. Chlamydia pneumoniae activates immune cells to produce cytokines that are responsible for the formation of atheromatous carotid lesions.. The study was carried out at the Department of Vascular, General and Transplantation Surgery, Wroclaw Medical University, in 2002-2003, on 100 consecutive symptomatic patients with internal carotid stenosis, who underwent an endarterectomy procedure. Each patient had their carotid artery sampled in order to find C. pneumoniae DNA using the nested PCR method and some cytokines (TGF-β, VEGF, FGF, TNF-α) using immunohistochemical examination. The control group consisted of 20 young organ donors who had been diagnosed with brain death and who had their healthy carotid artery harvested. Analogous genetic and immunohistochemical tests were performed.. We did not confirm the presence of either cytokines or C. pneumoniae in the healthy carotid arteries. The presence of FGF was probably due to intima fibroblast activity, which is responsible for elastin and collagen synthesis for the extracellular matrix. C. pneumoniae was discovered in 68% of patients with carotid plaques. Three cytokines (TGF-β, FGF, TNF-α) were detected in atherosclerotic internal carotid arteries as well.. Chronic infection by C. pneumoniae may exacerbate carotid plaque development and may lead to its destabilization.

Topics: Adult; Aged; Atherosclerosis; Carotid Arteries; Carotid Stenosis; Chlamydophila pneumoniae; Cytokines; Female; Humans; Male; Middle Aged; Plaque, Atherosclerotic; Polymerase Chain Reaction; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha; Young Adult

Inflammation plays an important role in the pathophysiological process after carotid artery stenting (CAS). Monocyte is a significant source of inflammatory cytokines in vascular remodeling. Telmisartan could reduce inflammation. In our study, we first found that, after CAS, the serum IL-1β, IL-6, TGF-β, and MMP-9 levels were significantly increased, but only MMP-9 level was elevated no less than 3 months. Second, we established a new in vitro model, where THP-1 monocytes were treated with the supernatants of human umbilical vein endothelial cells (HUVECs) that were scratched by pipette tips, which mimics monocytes activated by mechanical injury of stenting. The treatment enhanced THP-1 cell adhesion, migration and invasion ability, and the phosphorylation of ERK1/2 and Elk-1 and MMP-9 expression were significantly increased. THP-1 cells pretreated with PD98095 (ERK1/2 inhibitor) attenuated the phosphorylation of ERK1/2 and Elk-1 and upregulation of MMP-9, while pretreatment with telmisartan merely decreased the phosphorylation of Elk-1 and MMP-9 expression. These results suggested that IL-1β, IL-6, TGF-β, and MMP-9 participate in the pathophysiological process after CAS. Our new in vitro model mimics monocytes activated by stenting. MMP-9 expression could be regulated through ERK1/2/Elk-1 pathway, and the protective effects of telmisartan after stenting are partly attributed to its MMP-9 inhibition effects via suppression of Elk-1.

Topics: Aged; Benzimidazoles; Benzoates; Carotid Stenosis; Cells, Cultured; Chemokine CCL2; ets-Domain Protein Elk-1; Extracellular Signal-Regulated MAP Kinases; Female; Human Umbilical Vein Endothelial Cells; Humans; Interleukin-1beta; Interleukin-6; Male; Matrix Metalloproteinase 9; Middle Aged; PPAR gamma; Stents; Telmisartan; Transforming Growth Factor beta; Vascular Cell Adhesion Molecule-1

In the recent decades, carotid angioplasty and stenting (CAS) has been developed into a credible option for the patients with carotid stenosis. However, restenosis remains a severe and unsolved issue after CAS treatment. Restenosis is characterized by neointimal hyperplasia, which is partially caused by vascular smooth muscle cells (VSMC) proliferation. However, the molecular mechanism involved in the restenosis is still unclear. In this study, we demonstrated a functional crosstalk between two TGF-β superfamily signaling pathway members, Smad3 and BMPR2, in VSMC proliferation. Smad3 plays an important role in the TGF-β/Smad3 signaling pathway, and is significantly upregulated in the carotid artery with restenosis to promote VSMC proliferation. In contrast, BMP receptor II (BMPR2), an inhibitor of VSMC proliferation is downregulated in carotid restenosis. We further found that BMPR2 downregulation is mediated by miR-17-92 cluster, which is transcriptionally regulated by Smad3. Thus, Smad3 upregulation and Smad3/miR-17-92 cluster-dependent BMPR2 downregulation are likely to promote VSMC proliferation and restenosis. Taken together, our results may provide novel clues for early diagnosis of carotid restenosis and developing new therapeutic strategy.

Topics: Base Sequence; Bone Morphogenetic Protein Receptors, Type II; Bone Morphogenetic Proteins; Carotid Arteries; Carotid Stenosis; Cell Proliferation; Cells, Cultured; Down-Regulation; Humans; MicroRNAs; Molecular Sequence Data; RNA, Long Noncoding; Signal Transduction; Smad3 Protein; Transcription, Genetic; Transforming Growth Factor beta; Up-Regulation

In the present study, we aimed to deterimine the dose-related effects of ticagrelor, the first reversible inhibitor of the P2Y12 receptor, found in smooth muscle cells as well as platelets, during neointimal hyperplasia in a rabbit carotid anastomosis model.. This study was an experimental, prospective, randomized controlled study including 20 New Zealand white female rabbits (6-months old; weighing 2300 ± 300 g). Under general anaesthesia, the rabbits underwent transection of the right carotid artery and subsequent anastomosis of both ends. The study animals were divided into the following 4 groups: T1 (ticagrelor 5 mg/kg, orally, daily), T2 (ticagrelor 10 mg/kg, orally, daily), T3 (ticagrelor 20 mg/kg, orally, daily) and control (no ticagrelor treatment). The single oral doses were administered in phosphate-buffered saline. The control group received sterile phosphate-buffered saline (2 ml/kg/day, orally) for 3 weeks postoperatively. At the end of the study, the animals were killed, and the anastomosed segment of the right carotid artery and part of the left carotid artery were excised from each animal. Antibodies against transforming growth factor-β were used in staining of arterial sections, which was followed by histomorphological and immunohistochemical studies.. The median intimal thickness (2.0 ± 0.14 µm left vs 73.4 ± 35.8 µm anastomosed right arteries; P <0.05), the median medial thickness (70.8 ± 5.6 µm left vs 92.3 ± 4.5 µm anastomosed right arteries; P <0.05) and the index ratio of intimal thickness to medial thickness (0.03 ± 0.00 left vs 0.8 ± 0.35 anastomosed control right arteries; P <0.05) increased significantly in the anastomosed right arteries compared with the left carotid arteries in the control group. In the treatment groups, the intimal thickness (73.4 ± 35.8 µm in control group vs T1 32.7 ± 19;1 µm, T2 1.9 ± 0.09 µm and T3 2.2 ± 0.5 µm; P = 0.047, P = 0.009 and P = 0.009, respectively), carotid artery intima/media ratio (0.8 ± 0.35 in control group vs T1 0.4 ± 0.2, T2 0.03 ± 0.01 and T3 0.03 ± 0.01 in ticagrelor groups; P = 0.028, P = 0.009 and P = 0.009, respectively) and medial thickness (92.3 ± 4.5 µm in control group vs T2 65.6 ± 7.1 and T3 66.1 ± 7.6 µm; P = 0.009 and P = 0.009, respectively) decreased significantly in the anastomosed right arteries.. This study indicates that effective doses (10 and 20 mg/kg, daily) of the antiplatelet agent ticagrelor in a rabbit model may be beneficial in prevention of intimal hyperplasia. Restenosis due to intimal hyperplasia has been high. Ticagrelor has also been linked to inhibition of smooth muscle cell proliferation and, hence, reduced intimal hyperplasia.

Topics: Adenosine; Anastomosis, Surgical; Animals; Biopsy; Carotid Arteries; Carotid Stenosis; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Hyperplasia; Immunohistochemistry; Neointima; Platelet Aggregation Inhibitors; Purinergic P2Y Receptor Antagonists; Rabbits; Receptors, Purinergic P2Y12; Recurrence; Ticagrelor; Transforming Growth Factor beta

The role of inflammation in atherosclerosis is well recognized. We have evaluated the allele frequencies of the +869T/C and +915G/C polymorphisms (SNPs) at the TGF-beta1 gene and -1082G/A SNP at IL-10 promoter sequence, two well-known immunosuppressive and anti-inflammatory cytokines, in patients with carotid stenosis. Our data suggest a lack of association between these SNPs and the susceptibility to atherosclerosis although other reports have demonstrated this association. These results may be due to the pleiotropic effects of the cytokines and/or differences in haplotype combination that should be investigated to elucidate the role of TGF-beta1 and IL-10 polymorphisms in atherosclerosis.

Topics: Aged; Aged, 80 and over; Carotid Stenosis; Gene Frequency; Humans; Interleukin-10; Middle Aged; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Promoter Regions, Genetic; Protein Sorting Signals; Sequence Analysis, DNA; Transforming Growth Factor beta; Transforming Growth Factor beta1

We investigated the role and influence of platelet derived growth factor (PDGF) and transforming growth factor beta1 (TGF) in the pathologic mechanism at the basis of plaque instability regulating the expression of matrix metalloproteinases (MMPs).. Plaques obtained from 70 patients who underwent carotid endarterectomy were classified histologically as stable or unstable. Serum levels of PDGF and TGF were measured pre- and postoperatively. The serum activities of MMP-2 and MMP-9 were also analyzed. Human umbilical artery smooth muscle cells (HUASMCs) were stimulated in vitro with PDGF at various concentrations (20 and 50 ng/mL) and TGF (2 and 5 ng/mL) in a serum-free medium. The release of MMPs in the conditioned medium was assessed by enzyme-linked immunosorbent assay. Release of the MMPs was confirmed by Western blot analysis; their activity and expression were determined by zymography and reverse transcription-polymerase chain reaction. Specific inhibition tests were performed on HUASMCs to evaluate the role of these growth factors.. Forty-two (60%) patients had an unstable carotid plaque and 28 (40%) a stable plaque. Preoperatively, patients affected with unstable carotid plaques had higher PDGF and lower TGF plasma levels than patients with stable carotid plaques (P < .001); the levels returned to normal at 1 and 30 days postoperatively, compared with 20 non-operated healthy volunteers. Release, activity, protein level, and expression of MMPs in PDGF-stimulated HUASMCs were greater than in the controls (P < .001), whereas these values in the TGF-stimulated HUASMCs were lower (P < .001). The addition of monoclonal anti-PDGF antibodies decreased the release, activity, protein level, and expression of MMPs, whereas the addition of monoclonal anti-TGF antibodies increased the release, activity, protein level and expression of MMPs (P < .001).. TGF seems to be an important stabilizing factor and prevents plaque rupture through the decrease of MMPs.

Topics: Aged; Aged, 80 and over; Carotid Artery Diseases; Carotid Stenosis; Cells, Cultured; Endarterectomy, Carotid; Female; Gene Expression Regulation, Enzymologic; Humans; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Middle Aged; Muscle, Smooth, Vascular; Platelet-Derived Growth Factor; RNA, Messenger; Transforming Growth Factor beta; Transforming Growth Factor beta1

Collagen triple helix repeat containing 1 (Cthrc1) was identified in a screen for differentially expressed sequences in balloon-injured versus normal arteries. Cthrc1 expression was not detectable in normal arteries. However, on injury it was transiently expressed by fibroblasts of the remodeling adventitia and by smooth muscle cells of the neointima. It was also found in the matrix of calcifying human atherosclerotic plaques. CTHRC1 is a secreted 28-kDa protein that is glycosylated and highly conserved from lower chordates to mammals. A short collagen motif with 12 Gly-X-Y repeats appears to be responsible for trimerization of the protein and this renders the molecule susceptible to cleavage by collagenase. Cthrc1 mRNA expression levels are increased in response to transforming growth factor-beta and bone morphogenetic protein-4. Cell migration assays performed with CTHRC1-overexpressing fibroblasts and smooth muscle cells demonstrate that increased CTHRC1 levels are associated with enhanced migratory ability. Furthermore, CTHRC1 overexpression caused a dramatic reduction in collagen type I mRNA and protein levels. Our data indicate that the novel molecule CTHRC1 is transiently expressed in the arterial wall in response to injury where it may contribute to vascular remodeling by limiting collagen matrix deposition and promoting cell migration.

Topics: Amino Acid Motifs; Amino Acid Sequence; Animals; Aorta; Biopolymers; Calcinosis; Carotid Artery Injuries; Carotid Stenosis; Catheterization; Cell Adhesion; Cell Differentiation; Cell Movement; CHO Cells; Collagenases; Cricetinae; Cricetulus; Evolution, Molecular; Extracellular Matrix Proteins; Fibroblasts; Gene Expression Profiling; Glycoproteins; Humans; Molecular Sequence Data; Myoblasts; Myocytes, Smooth Muscle; Rats; Rats, Sprague-Dawley; Recombinant Fusion Proteins; RNA, Messenger; Sequence Alignment; Sequence Homology, Amino Acid; Signal Transduction; Species Specificity; Transforming Growth Factor beta; Vertebrates

Topics: Cardiovascular Diseases; Carotid Stenosis; Collagen; Follow-Up Studies; Humans; Longitudinal Studies; Procollagen; Prospective Studies; Time; Transforming Growth Factor beta; Transforming Growth Factor beta1

Migration of adventitial fibroblasts contributes to arterial remodeling after angioplasty. This study used vascular gene transfer of smad7 to investigate whether antagonism of transforming growth factor-beta1 signaling alters luminal loss and adventitial cell migration after balloon injury in rat carotid arteries.. Adenoviruses coordinating expression of beta-galactosidase (beta-gal) and smad7 or beta-gal and green fluorescent protein (GFP) were applied to the perivascular surface of common carotid arteries. Balloon injury was performed 4 days after gene transfer, and animals were killed at 3, 7, and 14 days after injury. Uninjured arteries only expressed adventitial beta-gal positive cells; however, after balloon injury in beta-gal- and GFP-transfected arteries, beta-gal-positive cells were observed within the medial layer of vessels and contributed to the population of cells within the neointima at 7 to 14 days. Overexpression of smad7 and beta-gal resulted in a significant reduction in the number of beta-gal-labeled cells in the neointima, concomitant with reduced luminal loss and decreased adventitial collagen content.. We provide the first evidence that vascular smad7 overexpression attenuates remodeling and contribution of adventitial fibroblasts to neointima formation after balloon angioplasty. Smad7 may represent a novel therapeutic target to reduce the incidence of restenosis.

Topics: Actins; Angioplasty, Balloon; Animals; Carotid Arteries; Carotid Artery Injuries; Carotid Stenosis; Cell Movement; Collagen; Gene Transfer Techniques; Genetic Therapy; Male; Rats; Rats, Sprague-Dawley; Secondary Prevention; Signal Transduction; Smad7 Protein; Transforming Growth Factor beta; Transforming Growth Factor beta1

Transforming growth factor-beta (TGF-beta) is a growth factor/cytokine involved in vascular remodeling and atherogenesis. Recent studies in apolipoprotein E-deficient mice have demonstrated a pivotal role of TGF-beta in the maintenance of the balance between inflammation and fibrosis in atherosclerotic plaques. Furthermore, inhibition of TGF-beta signaling has been shown to accelerate plaque formation and its progression toward an unstable phenotype in mice. However, if this mechanism is operative also in humans is still unknown. The aim of this study was to characterize the expression of TGF-beta1 in human carotid plaque and to correlate it with the extent of inflammatory infiltration and collagen content with the clinical signs of plaque instability.. Plaques were obtained from patients undergoing carotid endoarterectomy and divided into symptomatic and asymptomatic according to clinical evidence of recent transient ischemic attack or stroke. Plaques were analyzed for TGF-beta1 expression by Immunocytochemistry, Western, and Northern blotting analysis. Immunocytochemistry was used to identify CD68+ macrophages, CD3 T lymphocytes, HLA-DR+ cells, and alpha-smooth muscle cells. Procollagen and interstitial collagen content were analyzed by immunohistochemistry and Sirius Red staining, respectively.. Plaque TGF-beta1 mRNA was increased up to 3-fold in asymptomatic as compared with symptomatic plaques. Plaques from asymptomatic group had fewer (P<0.0001) macrophages and T lymphocytes compared with symptomatic plaques. TGF-beta1 gene was transcriptionally active as demonstrated by increased (P<0.0001) TGF-beta1 protein expression in asymptomatic plaques. Immunohistochemistry showed that TGF-beta was mainly expressed in plaque shoulder and was associated with a comparable increase (P<0.0001) in plaque procollagen and collagen content.. In conclusion, this study demonstrates the higher expression of TGF-beta1 in human asymptomatic lesions and provides evidence that TGF-beta1 may play an important role in the process of plaque stabilization.

Topics: Aged; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Arteriosclerosis; Carotid Stenosis; CD3 Complex; Collagen Type I; Female; Gene Expression; Humans; Immunohistochemistry; Macrophages; Male; Myocytes, Smooth Muscle; T-Lymphocytes; Transforming Growth Factor beta; Transforming Growth Factor beta1

Restenosis is responsible to approximately 30% of long-term failure following therapeutic vascular procedures. Thrombosis plays a key role in the development of restenosis. Thrombin-specific inhibitors have been considered as one type of candidates for the prevention of restenosis. Previous studies by our group demonstrated that a novel thrombin-specific inhibitor, hirulog-like peptide (HLP), reduced balloon catheter-induced neointima formation in rat carotid arteries. The present study examined the effect of HLP on angioplasty-induced restenosis in carotid arteries of atherosclerotic rabbits. New Zealand white rabbits were subject to air desiccation of the lumen of the right carotid arteries, then received high cholesterol/fat diet for 3 weeks. The rabbits were intravenously infused with HLP (1.6 mg/(kg/h)) or saline (n=7 per group) for 4 h started before angioplasty which dilated atherosclerotic lesions in right common carotid artery. Four weeks after the angioplasty, neointimal area, stenosis and neointima/media ratio in injured carotid arteries were reduced in atherosclerotic rabbits treated with HLP compared to saline controls by 62, 39 and 59% (P<0.05). The expression of tissue factor (TF) and transforming growth factor (TGF)-beta in the neointima of carotid arteries of rabbits treated with HLP was significantly weaker than saline controls (P<0.05 or <0.01). Activated partial thromboplastin time and bleeding time in HLP-treated rabbits were not significantly prolonged compared to controls. The results of the present study suggest that HLP may substantially reduce angioplasty-induced restenosis in atherosclerotic rabbits without increasing bleeding tendency. The inhibition on the expression of TF and TGF-beta in the neointima of the arterial wall may contribute to the preventive effect of HLP on restenosis in atherosclerotic rabbits.

Topics: Animals; Arteriosclerosis; Bleeding Time; Carotid Artery, Common; Carotid Stenosis; Collagen; Hirudins; Humans; Immunohistochemistry; Male; Partial Thromboplastin Time; Peptide Fragments; Rabbits; Rats; Recombinant Proteins; Recurrence; Thromboplastin; Transforming Growth Factor beta; Tunica Intima

Transcription factor activator protein-1 (AP-1) is activated and upregulated in injured arterial smooth muscle cells in vivo, yet the exact role of the AP-1--related pathway in vascular disease in vivo has remained unclear. We examined the role of the transfer of synthetic double-stranded cis-element decoy oligodeoxynucleotides (ODNs) in balloon-injured rabbit carotid arteries and the effects of these ODNs on neointimal thickening.. Transfection of fluorescein isothiocyanate--labeled ODNs using the hemagglutinating virus of Japan liposome method resulted in widespread distribution of fluorescent nuclear signals over the entire medial layer in injured arteries. Gel mobility shift assay revealed that AP-1 DNA binding was activated and that the AP-1 decoy reduced AP-1 DNA binding activity as a result of specific binding affinity to AP-1 in vivo. In morphometric analyses, AP-1 decoy led to a significant reduction in the neointimal area and a significant reduction in cell number and transforming growth factor-beta(1) production of human aortic smooth muscle cells under conditions of platelet-derived growth factor stimulation.. Because AP-1 decoy transfection in vivo dramatically prevented neointimal thickening in balloon-injured arteries, AP-1 may be a useful molecular target for gene therapy to reduce restenosis.

Topics: Adult; Animals; Binding Sites; Binding, Competitive; Carotid Artery Injuries; Carotid Artery, Common; Carotid Stenosis; Catheterization; Cell Count; Cell Division; Cells, Cultured; Disease Models, Animal; DNA; Fluorescein-5-isothiocyanate; Genetic Therapy; Humans; Liposomes; Male; Muscle, Smooth, Vascular; Oligonucleotides; Rabbits; Sendai virus; Transcription Factor AP-1; Transfection; Transforming Growth Factor beta; Transforming Growth Factor beta1; Tunica Intima

The transition from stable to rupture-prone and ruptured atherosclerotic plaques involves many processes, including an altered balance between inflammation and fibrosis. An important mediator of both is transforming growth factor (TGF)-beta, and a pivotal role for TGF-beta in atherogenesis has been postulated. Here, we determine the in vivo effects of TGF-beta inhibition on plaque progression and phenotype in atherosclerosis. Recombinant soluble TGF-beta receptor II (TGFbetaRII:Fc), which inhibits TGF-beta signaling, was injected in apolipoprotein E-deficient mice for 12 weeks (50 microg, twice a week intraperitoneally) as early treatment (treatment age 5 to 17 weeks) and delayed treatment (age 17 to 29 weeks). In the early treatment group, inhibition of TGF-beta signaling treatment resulted in a prominent increase in CD3- and CD45-positive cells in atherosclerotic lesions. Most profound effects were found in the delayed treatment group. Plaque area decreased 37.5% after TGFbetaRII:Fc treatment. Moreover, plaque morphology changed into an inflammatory phenotype that was low in fibrosis: lipid cores were 64.6% larger, and inflammatory cell content had increased 2.7-fold. The amount of fibrosis decreased 49.6%, and intraplaque hemorrhages and iron and fibrin deposition were observed frequently. TGFbetaRII:Fc treatment did not result in systemic effects. These results reveal a pivotal role for TGF-beta in the maintenance of the balance between inflammation and fibrosis in atherosclerotic plaques.

Topics: Animals; Apolipoproteins E; Arteriosclerosis; Carotid Stenosis; Disease Progression; Drug Administration Schedule; Fibrosis; Immunoglobulin Fc Fragments; Immunoglobulin G; Inflammation; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Phenotype; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Recombinant Fusion Proteins; Signal Transduction; Solubility; Transforming Growth Factor beta

To investigate the expression and localisation of transforming growth factor betas (TGF beta s) and their receptor CD105 (endoglin) in relation to calcification and bone formation in atherosclerotic lesions of human carotid arteries.. The TGF beta family regulates cellular growth, differentiation and angiogenesis and plays a key role in enchondral bone formation. CD105 is part of the TGF beta receptor complex preferentially expressed on endothelial cells (EC).. Immunohistochemical methods were used to determine the localisation of TGF beta isoforms 1, 2 and 3 and their spatial expression patterns in relation to calcification and bone formation in atherosclerotic lesions. Cellular sources of TGF beta s and CD105 were assessed using cell-type specific antibodies.. There was marked variability in TGF beta expression in different cell types associated with calcification. Smooth muscle cells (SMC) in the atheroma cap showed higher levels of TGF beta 3 and 2 than 1, but in the deep musculoelastic intima there were higher levels of TGF beta 1 and alpha-actin. All three TGF beta isoforms were expressed in monocyte-macro-phages. Giant cells associated with calcifications showed intense staining for TGF beta 2. TGF beta 1 was most strongly expressed on matrix and cells associated with bone formation. CD105 expression on SMCs and monocyte-macrophages was lower on cells in close association with calcification. SMCs associated with bone formation expressed high levels of CD105.. The different TGF beta isoforms exhibit distinct but overlapping patterns of expression, and support the hypothesis that they are involved in the process of calcification and bone formation in human atherosclerotic lesions. Lower expression of CD105 on cells associated with calcification may represent their state of lower responsiveness to TGF beta s.

Topics: Antigens, CD; Arteriosclerosis; Calcinosis; Carotid Arteries; Carotid Stenosis; Endoglin; Endothelium, Vascular; Humans; Muscle, Smooth, Vascular; Ossification, Heterotopic; Receptors, Cell Surface; Transforming Growth Factor beta; Vascular Cell Adhesion Molecule-1

The degree of cellularity in vascular lesions is determined by the balance between the migration and proliferation of cells relative to their rate of egress and apoptosis. Transforming growth factor-beta(1) can act as a potent antiproliferative and apoptotic factor for proliferating vascular cells. Our laboratory has previously identified cells cultured from human vascular lesions that are resistant to the antiproliferative effect of TGF-beta(1) due to an acquired mutation in the Type II receptor for TGF-beta(1). In the present studies, the expression of the Type I and II receptors in coronary and carotid atherosclerotic lesions was analysed by immunostaining, RT-PCR, and in situ RT-PCR. Levels of the Type I and Type II receptors varied widely within lesions, with the highest levels in the fibrous cap and at discrete foci within the lesion. Regions of smooth muscle-like cells (SMC) were commonly found that were Type I positive but Type II receptor negative. In 43 cell lines cultured from 126 human lesions, 84% of the lesion-derived cell (LDC) cultures exhibited functional resistance to the antiproliferative effect of TGF-beta(1). This resistance was conferred against TGF-beta(1), TGF-beta(2), and TGF- beta(3), but not interferon-gamma or mimosine. While normal SMC exhibited a four-fold increase in the rate of apoptosis after TGF- beta(1) treatment, most LDC were resistant to apoptosis in response to TGF-beta(1). Resistant cells exhibited selective loss of Type II receptor expression, and retroviral transfection of Type II receptor cDNA partially corrected the functional deficit. Thus, resistance to apoptosis may lead to the slow proliferation of resistant cell subsets, thereby contributing to the progression of atherosclerotic and restenotic lesions.

Topics: Activin Receptors, Type I; Apoptosis; Arteriosclerosis; Atherectomy; Carotid Stenosis; Cell Division; Cloning, Molecular; Coronary Disease; Endarterectomy, Carotid; Humans; Immunohistochemistry; Models, Cardiovascular; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type I; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Recombinant Proteins; Recurrence; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transcription, Genetic; Transfection; Transforming Growth Factor beta

The in vivo effect of transforming growth factor-beta 1 (TGF-beta 1) was studied in a model system in which arterial intimal thickening was induced by injury of rabbit arteries with a balloon catheter (BCI). Intimal area and its ratio to medial area in carotid arteries after BCI were significantly higher in rabbits treated with 10 micrograms/kg TGF-beta 1 and 10 mg/kg aspirin i.v. QD (TGF-beta 1 group) than in those treated with 10 mg/kg aspirin i.v. QD only (control group). Intimal cell numbers in the TGF-beta 1 and control groups were not significantly different from each other, but matrix volume in the intimal layer was significantly higher in the TGF-beta 1 group. By immunohistochemical and Northern blot analyses, the fibronectin content in carotid intimal and medial layers was greater in the TGF-beta 1 group compared with that in the control group. Thus, in intimal thickenings induced by BCI. TGF-beta 1 mainly enhanced the formation of matrix containing fibronectin. Moreover, the mRNAs of TGF-beta 1 and type II receptors were detected in carotid arteries 7 and 14 days after, but not before, BCI. Thus, TGF-beta 1 influences the process of intimal thickening induced by BCI through a receptor-mediated mechanism in vivo. The significance of this fact is discussed in relation to the development of atherosclerosis.

Topics: Animals; Carotid Artery, Common; Carotid Stenosis; Catheterization; Cell Count; Cell Size; Extracellular Matrix; Fibronectins; Male; Rabbits; Receptors, Transforming Growth Factor beta; RNA, Messenger; Transforming Growth Factor beta