Antiviral activities of atractylon from Atractylodis Rhizoma

Atractylodis Rhizoma is a traditional medicinal herb, which has antibacterial, antiviral, anti-inflammatory and anti-allergic, anticancer, gastroprotective and neuroprotective activities. It is widely used for treating fever, cold, phlegm, edema and arthralgia syndrome in South-East Asian nations. In this study, 6 chemical compositions of Atractylodis Rhizoma were characterized by spectral analysis and their antiviral activities were evaluated in vitro and in vivo. Among them, atractylon showed most significant antiviral activities. Atractylon treatment at doses of 10-40 mg/kg for 5 days attenuated influenza A virus (IAV)-induced pulmonary injury and decreased the serum levels of interleukin (IL)-6, tumor necrosis factor- and IL-1, but increased interferon- (IFN-) levels. Atractylon treatment upregulated the expression of Toll-like receptor 7 (TLR7), MyD88, tumor necrosis factor receptor-associated factor 6 and IFN- mRNA but downregulated nuclear factor-B p65 protein expression in the lung tissues of IAV-infected mice. These results demonstrated that atractylon significantly alleviated IAV-induced lung injury via regulating the TLR7 signaling pathway, and may warrant further evaluation as a possible agent for IAV treatment.