Response to treatment of murine schistosomiasis with recombinant IL-22 under different circadian timing

Abstract

ABSTRACT Response to treatment usually depends on the time of drug administration. Interleukin-22 (IL-22) is known for its protective effect against liver injury. Therefore, the aim was to study the effectiveness of the IL-22 treatment at different circadian timing on S. mansoni-infected mice. Mice grouping included; control group, mice infected with cercariae, and IL-22-treated groups. Treatment with IL-22 (0.36 µg/kg) was performed on infected mice either at 7 am, or 7 pm. Hepatic granuloma index (GI), levels of tumor necrosis factor-α (TNF-α), interleukin-17 (IL-17), IL-22, and immunoglobulin E (IgE) were measured. In addition, hepatic expressions of signal transducer and activator of transcription 3 (STAT3) and β-catenin genes were estimated. Infection with S. mansoni increased pro-inflammatory parameters, STAT3, and β-catenin mRNA significantly (P < 0.05) compared to the control group. IL-22 groups showed a significant reduction (P < 0.05) in liver GI, TNF-α, and β-catenin mRNA compared to infected mice. Moreover, it enhanced STAT3 gene expression (P < 0.05). IL-22 administration at 7 am reduced GI, IL-17, and IgE levels significantly (P < 0.05) compared to 7 pm values. The conclusion, IL-22 might have an immunotherapeutic effect. Its administration at 7 am was more effective in reducing hepatic granuloma and IgE, but further studies are needed to support these findings.