Significance Of Dynamic Changes Of Galectin-9 And It's Receptor Tim-3 In Murine Viral Myocarditis

ObjectiveTo detect the level of plasma Galectin-9 and the expression of Galectin-9 mRNA and it's receptor Tim-3 mRNA in myocardium of viral myocarditis mice at different phases,in order to explore the potential role of Gal-9 in the occurrence and development of viral myocarditis.MethodsA total of 58 five to six week old male Balb/c mice,with weight range from 16 to 18 gram,were randomly divided into CVB3 group(n=50) and control group(n=8).The mice in CVB3 group were inoculated with 0.10 ml liquid of TCID50 10-5/L Coxsackievirus B3.Eight mice in CVB3 group were sacrificed separately on day 7,10,14,28 after inoculation.The mice in control group were inoculated with 0.10 ml Eagle reagent,sacrificed on day 28.The myocardial tissue was extracted,and histopathologic examination of the heart were observed by lightmicroscope and the myocardial histopathology scores were calculated.The expression of Gal-9 mRNA and Tim-3 mRNA of myocardium were detected by real time polymerase chain reaction(RQ-PCR).Enzyme-linked immunosorbent assay(ELISA) was used to detect the level of serum Gal-9.Results 1.The incidence of myocarditis in which the mice inoculated CVB3 were 100%.Focal degeneration,necrotic lesions and bulky inflammatory cells infiltration appeared obviously in the myocardium,showed typical viral myocarditis alterations.2.The concentrations of plasma Gal-9 in CVB3 group were elevated gradually after virus inoculation,and reached the peak on day 10.Then it decreased on day 14,and almost recovered to the normal level on day 28.3.There were significant differences in the concentrations of plasma Gal-9 between on days 7,10,14 and control group,respectively(F=16.64, p< 0.01).4.The concentrations of plasma Gal-9 in mice of CVB3 group were positively correlated with myocardial pathologic scores(r=0.75,P<0.05).5.The expression of Gal-9 mRNA in myocardium in CVB3 group were elevated gradually after virus inoculation.It increased significantly at the 7th day,and arrived the highest level at the 10th day,then decreased at the 14th day,and recovered to the normal level at the 28th day.6. There were significant differences in the expression of Gal-9 mRNA between on days 7,10 and control group,respectively(F=3.94,p<0.01).7.The expression of Gal-9 mRNA in myocardium in CVB3 group were positively correlated with myocardial pathologic scores(r=0.74,p<0.05).8.In CVB3 group,the level of plasma Gal-9 were positively correlated with the expression of Gal-9 mRNA in myocardium(r=0.71,p<0.05).9. There were significant differences in the expression of Tim-3 mRNA between on days 7,10,14 and control group,respectively(F=3.94,p<0.01).10.The expression of Tim-3 mRNA in myocardium in CVB3 group were elevated gradually after virus inoculation.It increased significantly on the 7th day, and arrived the highest level on the 10th day,and decreased on the 14th day,and recovered to the normal level on the 28th day.11.The expression of Tim-3 mRNA in myocardium in CVB3 group were positively correlated with myocardial pathologic scores(r=0.68,p<0.05). Conclusions1.After virus inoculation, the concentration of plasma Gal-9 and the expression of Gal-9 mRNA and Tim-3 mRNA in myocardium increased significantly.It suggested that Gal-9 and it's receptor Tim-3 may play a role in the development of viral myocarditis.2.The concentration of plasma Gal-9 and the expression of Gal-9 mRNA in myocardium were positively correlated with the severity of myocardium.It indicated certain connection between the expression of Gal-9 and severity of inflammation lesions in mice with viral myocarditis.The concentration of plasma Gal-9 may serve as a indicator of the severity of myocardium.