Coxsackievirus B3 (CVB3) is a primary causative agent of viral myocarditis (VMC), which can lead to both acute and chronic cardiac inflammation accompanied by progressive heart failure and arrhythmias. Although CVB3 has been implicated in various forms of programmed cell death, whether it triggers necroptosis and the underlying mechanisms remains unclear. This study aimed to investigate the role and mechanism of CVB3-induced necroptosis and its effect on viral replication. Using both in vitro and in vivo models, we demonstrated that CVB3 infection significantly upregulates the expression of key necroptotic markers RIP1 and RIP3 in HeLa cells and mouse myocardial tissues. This upregulation was accompanied by elevated intracellular reactive oxygen species (ROS) levels and suppression of the Nrf2/HO-1 antioxidant pathway. Intervention with the necroptosis inhibitor Necrostatin-1 (Nec-1) or the ROS scavenger N-acetylcysteine (NAC) markedly attenuated cell death, suppressed viral replication, and ameliorated myocardial injury and inflammatory responses in infected mice. Mechanistically, CVB3 inhibits the Nrf2/HO-1 pathway, thereby inducing substantial ROS accumulation that promotes necroptosis. This effect can be reversed by NAC treatment. Our study reveals a novel mechanism through which CVB3 induces ROS-dependent necroptosis via the suppression of the Nrf2/HO-1 pathway, providing new insights into the pathogenesis of viral myocarditis and suggesting potential therapeutic strategies.
Viral myocarditis (VMC), predominantly driven by Coxsackievirus B3 (CVB3) infection and the resultant excessive immune response, lacks effective treatments and specific antiviral drugs in clinical practice. Chlorogenic acid (CGA) has been proven to have significant antiviral and anti-inflammatory properties. This study evaluated the potential and mechanism of action of CGA against CVB3-induced viral myocarditis. Our research results showed that CGA significantly alleviated myocardial tissue damage in vivo. This protective effect was accompanied by effective inhibition of myocardial inflammatory responses and viral replication. Further in vitro experiments confirmed that CGA significantly inhibited the replication of CVB3 in a dose-dependent manner, and its inhibitory effect mainly targeted the replication stage of the viral life cycle. Mechanistically, CGA treatment correlates with reduced ZBP1 expression and accelerated ZBP1 degradation involving the ubiquitin–proteasome pathway, accompanied by suppressed activation of PANoptosis markers. These findings suggest that CGA alleviates CVB3-induced myocarditis through concerted antiviral and anti-inflammatory effects, with ZBP1-mediated PANoptosis as a potential contributing mechanism.