Experimental study on mouse myocardial injury induced by Se-deficiency and viral superinfection of CVB4 and CVB3m

Abstract

Objective To investigate relation between Se-deficiency andsuperinfection of both CVB4 and CVB3m in mouse myocardial injury.Methods The mice (Kunming line) were divided into 4 groups on the Se contents and superinfection of Coxsackie virus B (CVB). Group1:Se-deficient,without CVB; Group 2: Se-rich without CVB; Group 3:, Se-deficient with CVB; and Group 4: Se-rich with CVB. The mice were fed with Se-deficient food containing lower protein and Se was applied by adding the Se into the drinking water for Se-rich group. For the CVB superinfection groups, the 7-day-old baby mice were inoculated with CVB4. After 1 week interval, the mice inoculated with CVB4 were superinfected with CVB3m .The mice were killed and their myocardial tissue sections were examined under lightmicroscope and electronic microscope at day 7,day 14 and day 21,respectively after CVB3m superinfection.Results The result showed that the myocardium was lightly damaged and the activity of cytochrome oxidase of myocardium decreased in Group 2 compared with those in Group 1.The result also indicated that myocardial injury rate was as high as 63.6%,and the myocardial injury and necrosis area was larger in Grope 4 than those in Group 2 and Group 3.The serological test showed that the titer of neutralizing antibody against CVB3m was 1:256 and 1:512 in Group 4 and in Group 3,respectively.All the results suggested that the interaction between Se-deficiency and superinfection of CVB4and CVB3m intensified the mouse myocardial damage. Conclusions Se-deficiency was one of the factors for myocardial injury in Keshan Disease and the superinfection of two types of CVBs might play a role in the incidence of Keshan Disease and selenium might play roles of antivirus and virus repression to some extent.