ReDuNing, a patented Chinese medicine, reduces the susceptibility to H1N1 influenza of mice loaded with restraint stress

Abstract Introduction ReDuNing (RDN), a patented traditional antipyretic-detoxicate Chinese medicine, has been widely applied as an anti-inflammatory and anti-infectious drug in Chinese clinics. However, relative experimental data on anti-influenza virus and its subsequent viral pneumonia by RDN are limited. In this study, restraint stress mice model, which could mimic the physiological conditions of the population susceptible to influenza infection, was applied to investigate the protective effect of RDN against influenza. Methods Mice were infected with H1N1 influenza virus 3 days after restraint, and RDN was administered to mice the day after stress by intraperitoneal injection for 7 days. Body weight and mortality were recorded every day. Histopathologic changes, lung index, nucleoprotein (NP) gene expressions and inflammatory markers in the lungs were also measured. Results RDN administration significantly decreased lung index, ameliorated lung histopathologic damage and decreased lung NP gene expression in influenza-infected mice loaded with restraint stress. It also decreased phosphorylated inhibitor of nuclear factor kappa B (p-IκB), nuclear factor-kappa B (NF-κB) protein level and interleukin-1β (IL-1β) mRNA expression, increased interferon inducible transmembrane 3 (IFITM3) and mitochondrial antiviral signaling (MAVS) gene expression. Conclusions This study provided preliminary support to suggest that RDN can reduce the susceptibility to, and the severity of influenza in restraint-stressed mice. The study also supported the potential of implementing RDN as an antiviral and its impact as potential anti-influenza treatments which rebalances homeostasis in the body caused by stress.