RESUMO
IMPORTANCE: Aquaculture is essential for ensuring global food security by providing a significant source of animal protein. However, the spread of the white spot syndrome virus (WSSV) has resulted in considerable economic losses in crustacean industries. In this study, we evaluated the antiviral activity of rhein, the primary bioactive component of Rheum palmatum L., against WSSV infection, and many pathological aspects of WSSV were also described for the first time. Our mechanistic studies indicated that rhein effectively arrested the replication of WSSV in crayfish by modulating innate immunity to inhibit viral gene transcription. Furthermore, we observed that rhein attenuated WSSV-induced oxidative and inflammatory stresses by regulating the expression of antioxidant and anti-inflammatory-related genes while enhancing innate immunity by reducing total protein levels and increasing phosphatase activity. Our findings suggest that rhein holds great promise as a potent antiviral agent for the prevention and treatment of WSSV in aquaculture.