To study the diagnostic method of slight viral myocarditis in the field of forensic pathology, slight viral myocarditis model was induced in Balb/c murine by coxsackie virus B3. Organs of hearts, livers, spleens, lungs and kidneys were examined through routine pathological methods. Pathological changes at different levels of these organs were observed. The results indicated that viral myocarditis was a kind of disease with multiple organ alterations and that the pathological observation and comprehensive analysis of multiple organs was one of the useful methods for diagnosing slight viral myocarditis.
Animals ; Coxsackievirus Infections/pathology* ; Female ; Forensic Medicine ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis/virology*

Autopsy ; Coxsackievirus Infections ; Enterovirus ; isolation & purification ; Enterovirus B, Human ; isolation & purification ; Enterovirus Infections ; Hand, Foot and Mouth Disease ; pathology ; virology ; Humans ; Infant ; Male

OBJECTIVETo investigate the dynamic expression and role of vitamin D receptor (VDR) in the myocardium of mice with viral myocarditis (VMC).

METHODSOne hundred and twenty 4-week-old male BALB/c mice were selected and assigned into control (n=40) and experimental groups (n=80). The mice in the experimental group were injected intraperitoneally with Coxsackievirus B3 to establish the model of VMC, while the mice in the control group were injected intraperitoneally with an equal volume of DMEM solution. Fifteen mice in the experimental group and ten mice in the control group were sacrificed at 3, 7, 14, or 28 days after injection, and the myocardial specimens were obtained. The dynamic expression of VDR in the myocardium was determined by the immunohistochemical technique. The pathological changes in the myocardium were examined using hematoxylin and eosin staining.

RESULTSIn the experimental group, the mice had significantly increased expression of VDR after virus injection (P<0.01); the expression of VDR reached the peak at 7 days after injection, and then declined gradually; the expression of VDR remained high at 28 days after injection. At 3, 7, 14, and 28 days after injection, the expression of VDR in the experimental group was significantly higher than that in the control group (P<0.01). Moreover, in the experimental group, the changes in the pathological score of the myocardium were in accordance with the changes in the expression of VDR; the expression level of VDR in the myocardium was positively correlated with the pathological changes in the myocardium in the experimental group (P<0.01).

CONCLUSIONSVDR may be involved in the inflammatory-immune process in the pathogenesis of VMC.

Animals ; Coxsackievirus Infections ; metabolism ; Enterovirus B, Human ; Immunohistochemistry ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; metabolism ; pathology ; Myocardium ; chemistry ; pathology ; Receptors, Calcitriol ; analysis ; physiology

Animals ; Coxsackievirus Infections ; metabolism ; pathology ; physiopathology ; Enterovirus B, Human ; Female ; Glutathione Peroxidase ; metabolism ; Male ; Mice ; Myocarditis ; virology ; Oxidative Stress ; drug effects ; Selenium ; pharmacology ; Superoxide Dismutase ; metabolism

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

OBJECTIVETo study the state of oxidative stress in patients with acute coxsackie virus myocarditis (ACM), and to investigate the pathological chain reactions of a series of free radicals and oxidative and lipoperoxidative damages in their bodies.

METHODSEighty ACM patients and 80 healthy adult volunteers (HAV) were enrolled in a case-control study, in which concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma and LPO in erythrocytes (RBC), vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in RBC were determined by using spectrophotometric assays.

RESULTSCompared with the average values (AV) of the above biochemical parameters (BP) in the HAV group, the AV of NO in plasma, and LPO in plasma and RBC in the ACM group were significantly increased (P = 0.0001), while the AV of VC, VE, beta-CAR, SOD, CAT and GSH-Px in the ACM group were significantly decreased (P = 0.0001). The values of the above BP were used to estimate the relative risk ratio (RR) between the ACM group and the HAV group; the RR and its 95% confidence interval were 12.467 (5.745-27.051), 4.333 (2.126-8.834), 6.517 (3.225-13.618), 3.310 (1.598-6.858), 31.000 (12.611-76.201), 4.663 (2.228-9.759), 11.769 (5.440-25.462), 3.043 (1.486-6.229) and 6.594 (3.045-14.281) respectively, and their P levels ranged from 0.002 to 0.0001. The results were as follows: D = 22.143 - 0.017SOD + 0.008NO + 0.244LPO in RBC, Eigenvalue = 13.659, Canonical correlation = 0.965, Wilks' lambda = 0.068, chi 2 = 420.212, P = 0.0001. The correct rate of discrimination to the ACM group and to the HAV group was 87.5% and 95.0%, respectively, and 91.3% of originally grouped cases was correctly classified.

CONCLUSIONThe findings in this study suggested that the oxidative stress in bodies of ACM patients was severely aggravated, and marked high oxidative constituents and low antioxidants and antioxidases in the human body might increase the relative risk of inducing acute coxsackie virus myocarditis, and measuring the values of NO in plasma, SOD and LPO in RBC might increase the correct rates of discriminatory analysis of the ACM.

Adolescent ; Adult ; Antioxidants ; analysis ; pharmacology ; Case-Control Studies ; Coxsackievirus Infections ; physiopathology ; Female ; Free Radicals ; Humans ; Lipid Peroxidation ; Male ; Middle Aged ; Myocarditis ; pathology ; virology ; Oxidative Stress

OBJECTIVETo investigate the relationship between endothelial-to-mesenchymal transition (EndMT) and myocardial fibrosis in acute viral myocarditis (VMC).

METHODSTwenty-eight Balb/c mice were randomized into 3 groups: control group (n=8), VMC group(n=10) and intervention group(n=10). Mice in VMC and intervention groups were injected intraperitoneally(i.p) with single dose of coxsackievirus B3, mice in control group were injected with equal amount of viral-free vehicle. In the following day, mice in control and VMC groups were injected i.p with 0.1 ml of saline and intervention group with 0.1 ml of recombinant human bone morphogenetic protein 7(rh-BMP7) at a concentration of 300 μg/kg. The mice hearts were harvested after 7 d, cardiac collagen volume fraction (CVF) was calculated on picrosirius red-stained sections. mRNA and protein expression of TGF-β1, CD31, VE-cadherin, fibroblast special protein 1 (FSP-1) and α-smooth muscle actin (α-SMA) and collagen 1α1 in myocardiac tissues were detected by real-time RT-PCR and Western blot analysis, respectively.

RESULTSCompared to controls, overt fibrosis was presented in necrotic area of myocardium in VMC group. Meanwhile, marked increase of TGF-β1 expression accompanied with EndMT characterized by loss of endothelial phenotype (decreased expression of CD31 and VE-cadherin), gain of mesenchymal proteins (overexpression of FSP-1 and α-SMA) and increased synthesis of collagen was also demonstrated. Both EndMT and cardiac fibrosis were simultaneously reversed by TGF-β1 inhibition.

CONCLUSIONEndMT is involved in cardiac fibrosis in acute viral myocarditis, TGF-β1 might be a main mediator.

Acute Disease ; Animals ; Antigens, CD ; metabolism ; Cadherins ; metabolism ; Collagen ; metabolism ; Coxsackievirus Infections ; metabolism ; pathology ; Disease Models, Animal ; Endothelium ; pathology ; Fibrosis ; Male ; Mesoderm ; pathology ; Mice ; Mice, Inbred BALB C ; Myocarditis ; metabolism ; pathology ; virology ; Myocardium ; metabolism ; pathology ; Transforming Growth Factor beta1 ; metabolism

OBJECTIVE: In order to improve accuracy and reliability of forensic diagnosis of sudden cardiac death, pathogenesis and relationship between the viral myocarditis (VMC) and dilated cardiomyopathy (DCM) were investigated. METHODS: Improved immunohistochemical technique was used to detect the expression of the CAR in myocardium samples, including 22 deceased with VMC, 20 deceased with DCM and 16 control deceased. RESULTS: The brown staining on the cell membrane of myocardium showed positive result. There was a prominent CAR expression in VMC group and DCM group, which were statistically significant difference compared with control group (P < 0.05). CONCLUSION The CAR expression showed significantly higher in VMC and DCM groups. The viral infection can result in myocardial necrosis and impaired cardiac functions. These abnormalities can trigger a cascade of events that contributed to the progress of VMC to DCM.
Cardiomyopathy, Dilated/pathology* ; Case-Control Studies ; Coxsackie and Adenovirus Receptor-Like Membrane Protein ; Coxsackievirus Infections/complications* ; Death, Sudden, Cardiac ; Female ; Forensic Pathology ; Humans ; Immunohistochemistry ; Male ; Myocarditis/virology* ; Myocardium/pathology* ; Receptors, Virus/metabolism* ; Staining and Labeling

OBJECTIVE: To explore etiology and pathogenesis of viral myocarditis (VMC) and dilated cardiomyopathy (DCM). METHODS: The expression of Coxsackie B virus and adenovirus receptors (CAR) were detected with modified immunohistochemical (IHC) technique in myocardium of left ventricle, right ventricle, interventricular septum, and septal papillary muscle from 28 patients with viral myocarditis, 31 patients with dilated cardiomyopathy and 17 control patients (including normal, hypertension heart disease, myocardial infarction and coronary atherosclerotic heart disease). RESULTS: The brown staining on the cell membrane of myocardium represents positive result. 100% (28 of 28) of VMC patients (IHC surface integral: 4.3975 +/- 0.0365) and 84% (26 of 31) of DCM patients (4.2064 +/- 0.052 6) had prevalent CAR expression compared to 0% (0 of 19) control patients (0.073 1 +/- 0.0362). There were statistically significant differences between VMC/DCM and control patients (P < 0.05). CONCLUSION The prevalence of CAR expression was significantly higher in VMC and DCM patients (100% and 84% vs. 0% in control). In contrast, there was no difference found between VMC and DCM patients. These results suggest that both VMC and DCM involve viral etiology and could share a similar pathogenesis.
Adenovirus Infections, Human/complications* ; Cardiomyopathy, Dilated/virology* ; Case-Control Studies ; Coxsackie and Adenovirus Receptor-Like Membrane Protein ; Coxsackievirus Infections/complications* ; Death, Sudden, Cardiac ; Female ; Humans ; Immunohistochemistry ; Male ; Myocarditis/virology* ; Myocardium/pathology* ; Receptors, Virus/metabolism*

OBJECTIVETo investigate the dynamic changes of expression of matrix metalloproteinases-9 in myocardium of mice with viral myocarditis (VMC) and its significance in the pathogenesis of viral myocarditis.

METHODSVMC model was prepared by an injection of CVB3 in BALB/C mice. The mice receiving an injection of culture solution without virus were used as the control group. Cardiac tissues were obtained 7, 14, 21 and 28 days after injection and made into paraffin sections. Myocardial histopathologic changes were observed by hematoxylin-eosin staining and Masson staining. The expression of MMP-9, type I collagen and type III collagen in cardiac tissues were quantified by SABC immunohistochemical method.

RESULTSThe expression of MMP-9 in the VMC model group was observed on the 7th day, reached a peak on the 14th day, and was significantly higher than that in the control group at all time points (P<0.05). Compared with the control group, the expression of type I collagen in the VMC model group was up-regulated on the 21st day and reached a peak on the 28th day (P<0.05). The expression of type III collagen in the VMC model group was significantly higher than that in the control group on the 28th day (P<0.05). The expression of MMP-9 was positively correlated with myocardial histopathologic scores (r=0.832, P<0.05) and negatively correlated with type I collagen expression (r=-0.791, P<0.05).

CONCLUSIONSMMP-9 is over-expressed at the early stage in VMC mice, and participates in the pathological process of VMC through mediating the degradation metabolism of type I collagen. It may be an important factor that leads to myocardial collagen remodeling and myocardial fibrosis.

Animals ; Collagen Type I ; analysis ; Collagen Type III ; analysis ; Coxsackievirus Infections ; enzymology ; Enterovirus B, Human ; Immunohistochemistry ; Male ; Matrix Metalloproteinase 9 ; analysis ; Mice ; Mice, Inbred BALB C ; Myocarditis ; enzymology ; pathology ; Myocardium ; enzymology ; pathology