Coxsackievirus B causes myocardial injury through inducing pyroptosis

Abstract

Objective To observe the effect of pyroptosis in the myocardial injury caused by Coxsackievirus B (CVB), and to determine whether CVB cause myocardial inflammation through pyroptosis. Methods Newborn Balb/c mice at the age of 3 days were divided into 4 groups: control groups; infected with CVB type 3 (CVB3) intraperitoneally; treated with Ac-YVAD-CMK intraperitoneally once at the same time of viral inoculation, or three times at 1, 3, 5 days after CVB3 infected.The expression level of caspase-1 protein was determined by Western blotting.The myocardial injury of the treated mice was observed with HE section.HeLa cells were divided into eight groups: four groups were infected with CVB3 for various time periods while the other four groups were infected with CVB3 and treated with various doses of caspase-1 inhibitor. Results CVB3 infection induced caspase-1 activation in cardiac muscle.Compared with the mice infected with CVB3 alone, the treatment of caspase-1 inhibitor markedly reduced the level of cleaved caspase-1.Caspase-1 inhibitor also suppressed CVB3 replication as shown in Hela cells.The myocardium of the mice treated with caspase-1 inhibitor after CVB3 infection showed slightly inflammation and necrosis compared with mice infected with the virus only. Conclusion Suppression of pyroptosis can effectively relieve themyocardial injury.The pyroptosisplays a pathological role in the CVB-related myocardial diseases. Key words: Coxsackievirus B; Pyroptosis; Inhibitor; Myocardial injury