Objective To investigate the role and mechanism of RNA-Specific adenosine deaminase 3 (Adar3) in regulating macrophage polarization during Coxsackievirus B3(CVB3)-induced viral myocarditis (VM). Methods Bone marrow-derived macrophages (BMDM) from mice were cultured in vitro and induced into M1/M2 macrophages using interferon-gamma (IFN-γ)/lipopolysaccharide (LPS) or interleukin 4 (IL-4), respectively. The mRNA expression levels of Adar1, Adar2, and Adar3 in each group of cells were assessed by real-time quantitative PCR (qRT-PCR). Specific siRNAs targeting the Adar3 gene were designed, synthesized, and transiently transfected into M2 macrophages. The mRNA levels of M2 polarization-related marker genes-including arginase 1 (Arg1), chitinase 3-like molecule 3 (YM1/Chi3l3), and resistin-like molecule alpha (RELMα/FIZZ1)-were detected by qRT-PCR. RNA sequencing was performed to analyze the signaling pathways affected by Adar3. The expression levels of Wnt/β-catenin signaling pathway were further validated using qRT-PCR and Western blot. The adeno-associated virus overexpressing Adar3 was designed, synthesized, and injected into mice via tail vein. Three weeks later, a myocarditis mouse model was established. After an additional week, the phenotype and function of cardiac macrophages, as well as multiple indicators of VM (including echocardiography, body weight, histopathology and serology) were examined. Additionally, the protein levels of the Wnt/β-catenin signaling pathway were assessed. Results Compared to M0-type macrophages, the expression level of Adar3 was significantly increased in M2-type macrophages. After transfection of Adar3 siRNA, the mRNA levels of Arg1, YM1 and FIZZ1 in M2 macrophages were downregulated. RNA sequencing revealed 149 upregulated genes and 349 downregulated genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and subsequent validation experiments indicated that Adar3 modulated the Wnt/β-catenin signaling pathway. In vivo experiments demonstrated that Adar3 overexpression alleviated the cardiac dysfunction of VM mice. The proportion of M1 macrophages in the heart decreased, while the proportion of M2 macrophages increased. At the same time, the Adar3 overexpression activated the Wnt/β-catenin signaling pathway. Conclusion Adar3 promotes macrophage polarization toward the M2 phenotype by activating the Wnt/β-catenin signaling pathway, thereby alleviating VM.
Animals ; Adenosine Deaminase/metabolism* ; Macrophages/immunology* ; Wnt Signaling Pathway/genetics* ; Myocarditis/immunology* ; Mice ; Coxsackievirus Infections/metabolism* ; Male ; Mice, Inbred BALB C ; Enterovirus B, Human/physiology* ; beta Catenin/genetics*

Objective: To develop RT-nPCR assays for amplifying partial and complete VP1 genes of human enteroviruses (HEVs) from clinical samples and to contribute to etiological surveillance of HEV-related diseases. Methods: A panel of RT-nPCR assays, consisting of published combined primer pairs for VP1 genes of HEV A-C and in-house designed primers for HEV-D, was established in this study. The sensitivity of each RT-nPCR assay was evaluated with serially diluted virus stocks of five serotypes expressed as CCID Results: The sensitivity of RT-nPCR assays for amplifying partial VP1 gene of HEVs was 0.1 CCID Conclusion This RT-nPCR system is capable of amplifying the partial and complete VP1 gene of HEV A-D, providing rapid, sensitive, and reliable options for molecular typing and molecular epidemiology of HEVs in clinical specimens.
Capsid Proteins/genetics* ; Enterovirus A, Human/genetics* ; Enterovirus B, Human/genetics* ; Enterovirus C, Human/genetics* ; Enterovirus D, Human/genetics* ; Humans ; Molecular Epidemiology/methods* ; Molecular Typing/methods* ; Reverse Transcriptase Polymerase Chain Reaction/methods*

OBJECTIVETo investigate the effect of tranilast on myocardial fibrosis in mice with viral myocarditis (VMC).

METHODSMale balb/c mice (n=72) were randomly divided into control, VMC and tranilast groups (n=24 each). In the VMC and tranilast groups, the mice were infected with Coxsackie virus B3 (CVB3) to prepare VMC model, while the control group was treated with Eagle's medium. After modeling, the tranilast group was administrated with tranilast [200 mg/(kg.d)] until the day before sampling. On days 7, 14 and 28 after CVB3 or Eagle's medium infection, heart specimens (n=8) were taken and examined after Toluidine blue staining and Nissl staining for counts of mast cells (MC), hematoxylin-eosin staining for myocardial pathological changes, and Masson staining for myocardial fibrosis. The expression of CTGF and type I collagen (Col I) in the myocardial tissue was measured by RT-PCR and Western blot. The correlations of CTGF mRNA expression with MC counts and Col I expression were analyzed.

RESULTSThe myocardial pathological changes and collagen volume fraction in the VMC group were significantly higher than in the control group at all three time points (P<0.05). Tranilast treatment significantly decreased the myocardial pathological changes and collagen volume fraction compared with the VMC group (P<0.05). The mRNA and protein expression of CTGF and Col I increased in the VMC group compared with the control group, and the increases were reduced with tranilast treatment (P<0.05). The number of MC was positively correlated to CTGF mRNA expression on the 7th day and 14th day (r=0.439, P=0.049) in the VMC group. There were positive correlations between the mRNA expression of Col I and CTGF on the 7th day and 14th day (r=0.646, P=0.007) and the 28th day (r=0.326, P=0.031).

CONCLUSIONSTranilast may inhibit the aggregation of MC and down-regulate the expression of CTGF, relieving myocardial fibrosis of mice with VMC.

Animals ; Collagen Type I ; genetics ; Connective Tissue Growth Factor ; genetics ; Coxsackievirus Infections ; drug therapy ; Enterovirus B, Human ; Fibrosis ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; drug therapy ; Myocardium ; pathology ; RNA, Messenger ; analysis ; ortho-Aminobenzoates ; pharmacology

To identify the cause of an outbreak of acute hemorrhagic conjunctivitis (AHC) in Jiangxi (China) in 2010, 20 eye conjunctival swabs were first collected from AHC patients. Then, viruses were isola- ted and tested for human enterovirus 70, coxsackievirus A24 variant (CV-A24v) and adenovirus using the polymerase chain reaction. All CV-A24v isolates underwent sequencing of 3C and VP1 coding regions. Then, a phylogenetic tree was constructed for Jiangxi CV-A24v and worldwide CV-A24v based on,3C and VP1 regions, respectively. Ten out of 20 specimens were positive for CV-A24v, implying that the outbreak was caused by CV-A24v. The phylogenetic tree based on the 3C region showed that Jiangxi CV- A24v belonged to cluster 5 in genotype IV (GIV-C5) with strains isolated throughout the world after 2010, and were divided further into A and B lineages. Phylogenetic analyses of the VP1 region showed that all of the worldwide CV-A24v strains isolated after 2000 could be divided into five groups (1-5). Jiangxi CV-A24v was classified into group 5 and also divided further into A and B lineages upon analyses of the 3C region. These data suggested that CV-A24v causing AHC outbreaks in China in 2010 belonged to GIV-C3 and GIV-C5. At least two transmission lineages were circulated in Jiangxi in 2010. The classification of CV-A24v isolated after 2010 worldwide using the phylogenetic tree based on the VP1 region was almost consistent with that based on the 3C region and also had significant chronological clustering.
China ; epidemiology ; Conjunctivitis, Acute Hemorrhagic ; epidemiology ; virology ; Coxsackievirus Infections ; epidemiology ; virology ; Disease Outbreaks ; Enterovirus C, Human ; classification ; genetics ; isolation & purification ; Genotype ; Humans ; Molecular Sequence Data ; Phylogeny ; Viral Proteins ; genetics

OBJECTIVETo investigate the role and significance of cardiac mast cells and Toll-like receptor 4 (TLR4) in the development and progression of viral myocarditis (VMC).

METHODSForty-eight Balb/c mice were randomly divided into a control group (n=24) and a model group (n=24). Coxsackievirus B3 was intraperitoneally injected into the model group mice to establish a VMC model. In each group, cardiac tissues were collected from 8 mice at 7, 14 and 28 days after the model was established. The cardiac tissues were stained with hematoxylin and eosin as well as Masson trichrome to observe pathological changes in cardiac tissues. The number and degranulation of cardiac mast cells at each time point were measured and evaluated by toluidine blue staining and transmission electron microscopy. The mRNA and protein expression of TLR4 in cardiac tissues was measured by RT-PCR and immunohistochemistry. In the model group, the correlation between number of cardiac mast cells and mRNA expression of TLR4 at all time points was analyzed.

RESULTSThe model group had significantly higher pathological scores of cardiac tissues than the control group at all time points (P<0.05). The myocardial collagen volume fraction in the model group at 28 days was significantly higher than in the control group at all time points and higher than in the model group at 7 and 14 days (P<0.05). At each time point, the model group had a significantly increased number of mast cells (P<0.05), and significantly increased mRNA and protein expression of TLR4 (P<0.05) compared with the control group. In the model group, the number of cardiac mast cells was positively correlated with the mRNA expression of TLR4 at all time points (R²=0.877, P<0.05).

CONCLUSIONSMice with VMC have significantly increased numbers of cardiac mast cells and expression of TLR4 compared with control mice at all time points, suggesting that mast cells and TLR4 may play important roles in the inflammatory response and fibrosis of VMC.

Animals ; Coxsackievirus Infections ; immunology ; Enterovirus B, Human ; Female ; Mast Cells ; physiology ; Mice ; Mice, Inbred BALB C ; Myocarditis ; immunology ; Myocytes, Cardiac ; pathology ; Toll-Like Receptor 4 ; analysis ; genetics ; physiology

To identify the pathogen of acute hemorrhagic conjunctivitis (AHC) in Shandong Province in 2010, eye mucous swab samples were collected from 26 patients in Qingdao and Linyi City. Real time-PCR assays for EV70, CVA24 and Adenovirus were performed on these samples. The result showed 17 samples (65.39%) were CVA24 positive while all the samples for HEV70 and Adenovirus detection were negative, which implied that CVA24 was the causative pathogen of this outbreak. A total of 10 virus strains isolated on Hep-2 cells were identified as CVA24 through VP1 amplification and nucleotide sequence analysis. The nucleotide and amino acid homologies on VP1 region among these isolates were 99.3%-100.0% and 99.5%-100.0%, respectively, and the strains aggregated together to one clade in phylogenetic tree. These results showed that the CVA24 circulating in Qingdao and Linyi City belonged to one transmission chain. Shandong CVA24s segregated into 5 different clades, and great nucleotide divergence was observed be tween AHC isolates and others.
Amino Acid Sequence ; China ; epidemiology ; Conjunctivitis, Acute Hemorrhagic ; epidemiology ; virology ; Enterovirus C, Human ; chemistry ; classification ; genetics ; isolation & purification ; Genetic Variation ; Humans ; Molecular Sequence Data ; Phylogeny ; Sequence Homology, Amino Acid ; Viral Proteins ; chemistry ; genetics

To evaluate the effects of lentivirus-delivered short hairpin RNA (shRNA) on CVB3 infection in an animal model by RNA interference technique, we constructed a recombinant lentivirus expressing shRNA-3753 against the viral genome region 3753-3771, then transduced Lenti-sh3753 into mice infected with CVB3. We evaluated the antiviral ability of lenti-sh3753 by cytopathic effect (CPE), viral plaque assay and histological analysis of mice hearts. The results showed that Lenti-sh3753 exhibited a significant protective effect on cell viability and reduction of viral titers in supernatant of cell culture by specific inhibition on viral replication. Lenti-sh3753 also prolonged the mice survival and limited the viral production in mice hearts. These data proposed that Lenti-sh3753 can effectively inhibit CVB3 infection in a coxsackievirus-induced myocarditis model, suggesting its potential role in prevention and therapy of viral diseases.
Animals ; Coxsackievirus Infections ; drug therapy ; virology ; Down-Regulation ; Enterovirus B, Human ; genetics ; physiology ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; drug therapy ; virology ; RNA Interference ; RNA, Small Interfering ; genetics ; therapeutic use ; RNA, Viral ; genetics ; Virus Replication

OBJECTIVE: To study the mechanism of osteopontin (OPN) in viral myocarditis by observing the expression of OPN and collagen I (Col I) in mice myocardium. METHODS: The viral myocarditis models were achieved by infection with myocarditic coxsackievirus B3 (CVB3). The myocardium of mice was stained by HE and Masson staining, and the pathological scores and the collagen volume fraction (CVF )of myocardium were tabulated. The expression of Col I mRNA was measured by RT-PCR. The expression of OPN was detected by RT-PCR and ELISA. RESULTS: The histopathological examination revealed a prevalence of myocardial cell necrosis and obvious inflammation changes at the 7th day post-infection. Subsequently the inflammatory lesions were gradually absorbed. At the 28th day, the inflammatory cells had almost disappeared and obvious fibrosis occurred. The pathological scores and the expression of OPN mRNA were higher than those of the control group (P<0.05), and reached the highest level at the 7th day (P<0.05). From the 14th day, these parameters decreased,reflected also in the ELISA results. At the 7th day and the 14th day, the Col I expression was similar to that of control. Col I expression at the 21th and 28th days was higher than those of the control (P<0.05), and correlated positively to the CVF results. CONCLUSION The OPN mRNA expression increased in acute stage of VMC, and higher than that of the control group when in recovery stage, suggesting that OPN might be related to the inflammatory response in acute stage of, and promote the collagen synthesis of recovery stage.
Animals ; Collagen Type I ; genetics ; metabolism ; Coxsackievirus Infections ; metabolism ; Enterovirus B, Human ; isolation & purification ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; metabolism ; virology ; Osteopontin ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism

OBJECTIVETo study the effects of astragaloside on the expression of insulin-like growth factor-1 (IGF-1) and associated proteins in mice with viral myocarditis.

METHODSSixty-five 4-week-old BALB/C mice were randomly divided into 5 groups: normal control, astragaloside control, untreated myocarditis, low-dose and high-dose astragaloside-treated myocarditis. The BALB/C mice in the later three groups were intraperitoneally injected with CVB3. The low-dose and high-dose astragaloside-treated myocarditis groups were given astragaloside of 0.07 and 0.6 mg/kg•d, respectively by intragastric administration. Fifteen days later, the samples of blood and muscular tissues were obtained. The expression of IGF-1 in plasma was measured using ELISA. The levels of IGF-1 and associated proteins in muscular tissues were measured by immunohistochemistry. The expression of IGF-1 mRNA in muscular tissues was examined by RT-polymerase chain reaction (RT-PCR).

RESULTSThe expression of IGF-1 and associated proteins increased significantly in mice infected with CVB3. High-dose astragaloside treatment reduced the expression of IGF-1 and associated proteins, but low-dose astragaloside did not.

CONCLUSIONSHigh-dose astragaloside may reduce the expression of IGF-1 and associated proteins in mice with acute viral myocarditis, possibly thus providing protective effects on muscular tissues.

Acute Disease ; Animals ; Coxsackievirus Infections ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; therapeutic use ; Enterovirus B, Human ; Insulin-Like Growth Factor Binding Protein 3 ; analysis ; Insulin-Like Growth Factor I ; analysis ; genetics ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; drug therapy ; metabolism ; Myocardium ; chemistry ; RNA, Messenger ; analysis ; Receptor, IGF Type 1 ; analysis ; Saponins ; therapeutic use ; Triterpenes ; therapeutic use

Human Enterovirus C group (HEV-C) includes 17 serotypes, which can not be serotype-identified by neutralization test using antiserum pool for NPEV. In order to elucidate the genotypes and molecular evolution of HEV-C in Shandong Province, We selected the strains isolated from AFP cases between 1994-2009 to perform reverse transcriptase-polymerase chain reactions (RT-PCR) by the primers specific for entire VP1 coding gene of HEV-C and sequencing. The phylogenetic tree was then constructed among these VP1 nucleotide sequences and other prototype strains. Totally 12 Shandong local strains were obtained and separated into 4 genotypes, CVA20, CVA21,CVA24 and EV 96. The homologous comparison and phylogenetic analysis showed Shandong strains were distinct from prototype strains in each genotype. This report showed that different genotype HEV-C strains spread widely in Shandong Province.
Cell Line ; China ; Enterovirus C, Human ; classification ; genetics ; Genotype ; Humans ; Molecular Sequence Data ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction