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Abstract Objectives: To describe the feature of expression of syndecan-4 in serum, synovial fluid (SF) and synovium in rheumatoid arthritis (RA) patients, and to analyze the correlation of syndecan-4 with disease activity and serological characteristic of RA. Methods: Syndecan-4 in sera of 60 RA patients, 20 osteoarthritis (OA) patients, 20 healthy controls, and in SF of 25 RA patients and 25 OA patients were tested by enzyme linked immunosorbant assay. The expressions of syndecan-4 in synovium of RA and OA patients were detected by immunohistochemistry. The expression of syndecan-4 on synovial fibroblasts from RA and OA patients were detected by immunofluorescence. The correlation between serum synde-can-4 concentration and disease activity were analyzed in RA patients. Results: The serum syndedcan-4 concentration was significantly higher in RA patients than in OA patients and healthy controls, and was higher in rheumatoid factor (RF)-positive RA patients than in RF-negative ones. Syndecan-4 concentration in SF of RA patients was comparable with OA patients. Syndecan-4 expression in synovial tissue was similar between RA and OA patients. The syndecan-4 concentration was significantly lower in SF than in serum of RA and OA patients. Syndecan-4 concentration in both serum and SF was positively correlated with disease activity of RA patients. Conclusion: The serum syndecan-4 concentration was higher in RA patients than in OA patients, and significantly higher in RF-positive RA patients than in RF-negative ones. Syndecan-4 concentration in both serum and SF was positively correlated with disease activity of RA patients.
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Objective To evaluate the relationship between the shedding of syndecan-4(SDC-4) in lung tissues and ventilator-induced lung injury in rats. Methods Thirty pathogen-free healthy adult male Wistar rats, weighing 220-250 g, were divided into 3 groups(n=10 each)using a random number table:control group(group C), mechanical ventilation with traditional tidal volume(VT)group(group T-VT) and mechanical ventilation with high VTgroup(group H-VT). The animals were anesthetized with pento-barbital sodium and tracheostomized. The rats kept spontaneous breathing in group C. The rats were me-chanically ventilated for 4 h with the VTset at 6 ml∕kg in group T-VT and with the VTset at 40 ml∕kg in group H-VT. Blood samples were collected immediately after the end of ventilation for measurement of serum SDC-4 concentrations by enzyme-linked immunosorbent assay. The left lung was lavaged, and broncho-alveolar lavage fluid was collected for determination of interleukin-1beta(IL-1β), IL-18, tumor necrosis factor-alpha and SDC-4 concentrations by enzyme-linked immunosorbent assay. The lungs were removed for determination of the wet to dry weight ratio and expression of SDC-4 protein and mRNA in lung tissues(by Western blot and real-time polymerase chain reaction, respectively)and for examination of the pathological changes. The lung injury scores were recorded. Results Compared with group C, the wet to dry weight ratio, lung injury scores, concentrations of IL-1β, IL-18, tumor necrosis factor-alpha and SDC-4 in bron-cho-alveolar lavage fluid and concentrations of SDC-4 in serum were significantly increased, the expression of SDC-4 mRNA was up-regulated, and the expression of SDC-4 was down-regulated in group H-VT(P<005), and no significant change was found in the parameters mentioned above in group T-VT(P>005).Marked pathological changes of lung tissues were found in group H-VT. Conclusion A large shedding of SDC-4 in lung tissues may be involved in the pathophysiological mechanism of ventilatior-induced lung injury in rats.
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Objective To evaluate the role of syndecan-4 (SDC-4) in inflammatory responses of rats with ventilator-induced lung injury (VILI).Methods Twenty-four healthy male wild type Sprague-Dawley rats and 24 male SDC-4 gene knockout Sprague-Dawley rats,aged 2-3 months,weighing 200-220 g,were assigned into 2 groups (n =12 each) using a random number table:control group (group C)and VILI group.The animals were anesthetized with pentobarbital sodium and tracheostomized.The rats kept spontaneous breathing in group C.The rats were mechanically ventilated for 4 h in group VILI.Blood samples were taken from the femoral artery at the end of mechanical ventilation for detection of arterial oxygen partial pressure (PaO2).The animals were sacrificed after blood sampling.The left lung was lavaged,and the broncho-alveolar lavage fluid (BALF) was collected for determination of the tumor necrosis factor-α (TNF-α),interleukin-1beta (IL-1β) and IL-18 concentrations (by enzyme-linked immunosorbent assay) and total protein concentrations (by BCA assay).The right lungs were removed for determination of the wet to dry weight ratio (W/D ratio) and expression of TNF-α,IL-1β and IL-18 mRNA in lung tissues (by real-time polymerase chain reaction) and for examination of the pathological changes (with a light microscope).The lung injury scores were recorded.Results Compared with group C of wild type rats,PaO2 was significantly decreased,W/D ratio and lung injury scores were increased,the concentrations of total protein,TNF-α,IL-1β and IL-18 in BALF were increased,and the expression of TNF-α,IL-1β and IL-18 mRNA in lung tissues was up-regulated in group VILI of wild type rats (P＜0.05),and no significant change was found in the variables mentioned above in group C of gene knockout rats (P＞0.05).Compared with group C of gene knockout rats,PaO2 was significantly decreased,W/D ratio and lung injury scores were increased,the concentrations of total protein,TNF-α,IL-1β and IL-18 in BALF were increased,and the expression of TNF-α,IL-1β and IL-18 mRNA in lung tissues was up-regulated in group VILI of gene knockout rats (P＜0.05).Compared with group VILI of wild type rats,PaO2 was significantly decreased,W/D ratio and lung injury scores were increased,the concentrations of total protein,TNF-α,IL-1β and IL-18 in BALF were increased,and the expression of TNF-α,IL-1β and IL-18 mRNA in lung tissues was up-regulated in group VILI of gene knockout rats (P＜0.05).Conclusion SDC-4 can inhibit inflammatory responses of rats with VILI and is involved in the endogenous protective mechanism.
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INTRODUÇÃO: A cardiomiopatia chagásica crônica (CCC), doença de elevada morbimortalidade, associada à grave disfunção ventricular e a arritmias cardíacas, caracteriza-se histologicamente por intensa reação inflamatória multifocal, com pronunciada fibrose miocárdica. Diante da ausência de uma terapia eficaz para os pacientes com as formas mais graves da doença, torna-se crucial a descoberta de biomarcadores que possam identificar pacientes em estágios mais precoces, sob risco mais elevado para a progressão da doença. Neste contexto, surge a syndecan-4, uma glicoproteína transmembrana associada à inflamação e fibrose, cujos níveis estão aumentados em indivíduos com insuficiência cardíaca. OBJETIVO: Neste trabalho, avaliamos o padrão de expressão da syndecan-4 no tecido cardíaco de camundongos e de indivíduos com cardiomiopatia chagásica e a possível correlação entre a concentração sérica de syndecan-4 com grau de fibrose miocárdica e com fração de ejeção do ventrículo esquerdo em indivíduos com doença de Chagas...
INTRODUCTION: The hallmark of chronic Chagas cardiomyopathy (CCC) is the presence of a multifocal inflammatory reaction, which leads to myocardial fibrosis, often followed by ventricular dysfunction and arrhythmias. Syndecan-4 is a transmembrane glycoprotein associated with inflammation and fibrosis. Syndecan-4 levels are increased in subjects with heart failure and it has been proposed as a biomarker to predict cardiovascular events. The expression of syndecan-4 is increased in the hearts of mice chronically infected with Trypanosoma cruzi, suggesting a role of this protein in the pathogenesis of CCC. OBJETIVE: Here we aimed to evaluate the pattern of expression of syndecan-4 in heart tissue of mice and subjects with Chagas cardiomyopathy, and to correlate with the degree of inflammation and fibrosis, as well as to determine the correlation of syndecan-4 serum concentration with the degree of myocardial fibrosis and with left ventricular ejection fraction in subjects with Chagas disease...
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Chagas Disease/complications , Chagas Disease/diagnosis , Chagas Disease/immunology , Chagas Disease/microbiology , Chagas Disease/pathology , Chagas Disease/transmissionABSTRACT
Objective Inflammation plays a critical role in the presence , development and maintenance of atrial fibrillation ( AF) , but it remains unclear what factors induce inflammation in AF patients , especially in those with valvular heart disease ( VHD) . The aim of this paper was to investigate the role of the shedding of Syndecan -4 in left atrial inflammation in patients with valvular atrial fibrillation. Methods Sixty VHD patients scheduled for valvuloplasty or valve replacement surgery were divided into three groups of equal number:sinus rhythm (SR), paroxysmal atrial fibrillation (PaAF), and persistent atrial fibrillation (PeAF).Another 10 pa-tients with congenital heart disease but no valve damage and atrial fibrillation were included in a control group .Baseline clinical data were recorded and tissues were obtained from the left atrial appendage during operation .The expressions of iNOS , HMGB1, and Syn-decan-4 in the left atrium were detected by Western blot , and the pathological changes of the left atrial tissue observed by HE staining . Results Western blot analysis was performed to detect expression levels of proteins .The iNOS level was significantly higher in pa-tients from the paroxysmal AF group (1.61 ±0.10) and persistent AF group (1.67 ±0.08) than those from sinus group (1.06 ± 0.11) and control group (1.02 ±0.12), as was the protein level of HMGB1 (0.63 ±0.05, 0.95 ±0.10, 0.45 ±0.07 and 0.46 ± 0.06 in paroxysmal AF group, persistent AF group, sinus group and controlgroup respectively ).Inflammatory cell infiltration in-creased, while syndecan 4 was down-regulated in AF groups.All these comparisons were significant (P<0.05). Conclusion The decreased expression of Syndecan-4 and enhanced inflammatory response in the left atrial tissue indicate that the shedding of Synde-can-4 may play a role in the presence and development of inflamma-tion in the left atrium .
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BACKGROUND AND OBJECTIVES: Differentiation and de-differentiation of vascular smooth muscle cells (VSMCs) are important events in atherosclerosis and restenosis after angioplasty. MicroRNAs are considered a key regulator in cellular processes such as differentiation, proliferation, and apoptosis. Here, we report the role of new miR-18a-5p microRNA and its downstream target genes in VSMCs and in a carotid balloon injury model. MATERIALS AND METHODS: Expression of miR-18a-5p and its candidate genes was examined in VSMCs and in a carotid artery injury model by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and microRNA microarray analysis. VSMC differentiation marker genes including smooth muscle (SM) alpha-actin and SM22alpha were determined by Western blot, qRT-PCR, and a SM22alpha promoter study. Gene overexpression or knockdown was performed in VSMCs. RESULTS: miR-18a-5p was upregulated in the rat carotid artery at the early time after balloon injury. Transfection of the miR-18a-5p mimic promoted the VSMC differentiation markers SM alpha-actin and SM22alpha. In addition, miR-18a-5p expression was induced in differentiated VSMCs, whereas it decreased in de-differentiated VSMCs. We identified syndecan4 as a downstream target of miR-18-5p in VSMCs. Overexpression of syndecan4 decreased Smad2 expression, whereas knockdown of syndecan4 increased Smad2 expression in VSMCs. Finally, we showed that Smad2 induced the expression of VSMC differentiation marker genes in VSMCs. CONCLUSION: These results indicate that miR-18a-5p is involved in VSMC differentiation by targeting syndecan4.
Subject(s)
Animals , Rats , Actins , Angioplasty , Antigens, Differentiation , Apoptosis , Atherosclerosis , Blotting, Western , Carotid Arteries , Carotid Artery Injuries , Cell Differentiation , Microarray Analysis , MicroRNAs , Muscle, Smooth , Muscle, Smooth, Vascular , Polymerase Chain Reaction , Smad2 Protein , Syndecan-4 , TransfectionABSTRACT
Objective Aim of the study is to investigate the expression of syndecan-4 and nuclear factor κB(NF-κB) in the kidney of rat with chronic fluorosis,and to reveal the mechanism of kidney damage resulted from the toxicity of excessive amount of fluoride.Methods According to body mass and sex,sixty SD rats were randomly divided to three groups according to body mass and fed with different contents of fluoride:control group with normal tap-water(＜ 0.5 mg/L fluoride),small dosage of fluoride exposure group (adding 10 mg/L fluoride in tap-water) and large dosage of fluoride exposure group (50 mg/L fluoride) for six months.The protein level of syndecan-4 and NF-κB in the kidney was detected by Western blotting and syndecan-4 mRNA level by quantitative real time PCR.Results As compared to the control group[(100.0 + 8.1)％],the expression of syndecan-4 at protein level in the kidney of rat was significantly increased in the small dosage of fluoride exposure group [(198.5 + 5.6)％,P ＜ 0.05] and large dosage of fluoride exposure group [(209.2 + 13.0)％,P ＜ 0.05]; the protein levels of NF-κB in the small dosage of fluoride exposure group[(284.4 + 11.1)％,P ＜ 0.05] and in the large dosage of fluoride exposure group[(343.2 + 2.9)％,P ＜ 0.05] were significantly increased than that of the control group[(100.0 ± 10.7)％].The mRNA levels of syndecan-4 in the kidney in the small dosage of fluoride exposure group and large dosage of fluoride exposure group(0.431 + 0.058 and 0.453 ± 0.065,both P ＜ 0.05,respectively) were significantly increased than that of the control(0.128 + 0.026).Conclusions The increased expression of NF-κB in the kidney is induced by increased expression of syndecan-4,which may be involved in kidney damage of chronic fluorosis.
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Objective To identify the candidate genes in the vicinity of a susceptibility locus (urinary albumin 1,UA-1) contributing to the development of albuminuria in type 2 diabetic KK/Ta mice. Methods Total RNA was extracted from the kidneys of KK/Ta (n=3) and BALB/c (n=2) mice at 20 weeks of age.The gene expression profile in kidney was investigated using the Affymetrix Murine Genome U74Av2 array.Competitive RT-PCR was used to confirm the differential expression of syndecan-4 which located in the vicinity of UA-1.Genome DNA was extracted from KK/Ta and BALB/c mice.DNA sequence analysis of the coding and promotor region of syndecan-4 gene was conducted. Results In the vicinity of the susceptibility locus (UA-1)contributing to the development of albuminuria in type 2 diabetic KK/Ta mice,10 candidate genes that showed differential expression were identified.Among them,the gene expression of syndecan-4in KK/Ta kidneys at 20 weeks of age was up-regulated by 26.1 times of age-matched BALB/c kidneys.Sequence analysis revealed two synonymous polymorphisms in the coding region (A93C and T216C) and three polymorphisms in the promoter region (-T263C,-T396C and -G669A) of the syndecan-4 gene.The TATA box was found at 321 bp upstream from the transcription start site,and the T263C polymorphism was located in the binding site of transcription factor Clox.Conclusions Syndecan-4 gene is mapped in the vicinity of the susceptibility locus contributing to the development of albuminuria in type 2 diabetes.The gene expression of syndecan-4 in KK/Ta kidneys is up-regulated than that in age-matched BALB/c kidneys at 20 weeks of age.Thus syndecan-4 may be one of the potential candidate genes responsible for diabetic nephropathy.Sequence differences in the promoter region influence the expression levels of syndecan-4 genes in KK/Ta kidneys.
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Objective To investigate the effect of syndecan-4 on the proliferation and extracellular matrix (ECM) secretion of human mesangial cells(HMC) stimulated by basic fibroblast growth factor (bFGF) and to evaluate the role of syndecan-4-PKCα pathway. Methods The expression of syndecan-4 in HMC was observed by immunofluorescence. After the down-regulation of syndecan-4 in HMC by RNA interference, the cell proliferation was detected by MTT. The secretion of fibronectin (FIN), type IV collagen, type Ⅰ collagen was assessed by ELISA. The copy number of syndecan-4 and PKCα was measured by fluorescent quantitation PCR at different time points. Results Syndecan-4 was expressed in HMC. bFGF could promote the cell proliferation and ECM secretion together with the PKCα copy number per million house-keeping genes of HMC, which could be reversed by the syndecan-4 siRNA transfection (MtT: 48-60 h, P<0.01; FiN: 24 h, P<0.01, 48-96 h, P<0.05; type Ⅳ collagen: 72-96 h, P<0.05; PKCa: 0 h, P<0.05, 12-48 h, P< 0.01). Conclusion Syndecan-4 may regulate the proliferation and ECM secretion of HMC stimulated by bFGF through syndecan-4-PKCα pathway.