The anti-inflammatory effect of arsenic trioxide effectively mitigates the pathogenic process in local chickens with avian leukosis.

Arsenic trioxide (ATO) is a classic first-line treatment for acute promyelocytic leukemia (APL). An increasing number of studies regarding the use of ATO in tumor treatment have shown consistently remarkable results. In this study, subgroup J avian leukosis virus (ALV-J) was used as a model virus, and different doses of ATO were used to treat ALV-J-positive chickens. Sexually mature green-shelled laying hens from the same ALV-J-positive offspring were grouped and treated with one of 3 different doses of ATO. The anti-inflammatory effects of different doses of ATO in ALV-J-positive chickens and their mechanisms were investigated by analyzing levels of inflammatory cytokines, antioxidant parameters and apoptosis-related genes. The results showed that ATO administration mitigated ALV-induced lymphoid leukosis in the liver. ATO inhibited the activation of the TLR4/MyD88/NF-κB signaling pathway and downregulated the expression levels of the inflammatory cytokines IL-1β, IL-6 and TNF-α. The SOD and GSH-Px activities were also increased, and the MDA content was decreased in the serum of ALV-J-positive chickens treated with different doses of ATO, so the antioxidant capacity of ALV-J-positive chickens was improved. The mRNA expression levels of p53, p21 and Bcl-2 in the livers of ALV-J-positive chickens treated with different doses of ATO were significantly downregulated, which induced the apoptosis of tumor cells and slowed the inflammatory response. The combined analysis revealed that the therapeutic effect of 2 mg/kg/dose ATO was superior to that of the other 2 treatments (0.5 and 1 mg/kg/dose ATO). In conclusion, the anti-inflammatory effect of ATO can effectively alleviate the ALV-J pathogenic process. ALV-J serves as a model virus for antiviral tumor research, while ATO provides references for the treatment of such tumors.