The Effect of Silibinin on the Expression of TLR7, ISG15, and SOCS1 in Peripheral Blood Mononuclear Cells of Hepatitis C Infected Patients in Comparison with Interferon-α

Background: Silibinin (silibinin A) is the most active silymarin component, which acts both as a hepatoprotective [1] and an antiviral agent. The present study investigated the silibinin effect on IFN-related innate immune genes in PBMCs from HCV-infected patients. Method: 22 chronic HCV patients, including 10 IFN responders and 12 non-responders, were included. Their isolated PBMCs were treated for 6 hours in the presence of silibinin, IFN-α, or their combination. The transcription level of TLR7, ISG15, and SOCS1 genes was compared using real-time PCR. Result: Our result showed that IFN-α induced a significant up-regulation of TLR7 and ISG15 in PBMCs of both responder and non-responder groups. Nevertheless, the SOCS1 gene was not significantly changed in the non-responder group (P=0.32). The combination of IFNα- and silibinin showed a similar pattern to IFN-α alone. By itself, silibinin did not leave a significant change on the expression level of the studied genes . Conclusion: The results indicated that silibinin did not enhance or suppress the expression level of TLR7, ISG15, and SOCS1 genes. Therefore, it has been suggested that its anti-inflammatory role might be devoid of IFN pathways.