The effect of silymarin on the expression of chemokine receptors in T helper 1 (Th1) cells

Background: Silymarin, apolyphenolic flavnoid derived from milk thistle (Silybum marianum), is known to have anti-inflammatory, hepatoprotective, and anticarcinogenic effects. The aim of this study was to investigate the effect of silymarin on the chemokine receptor of (T helper) Th1 cells. Methods: Peripheral blood mononuclear cells (PBMCs) from 8 healthy individuals were activated with Conconavalin 'A' and treated with silymarin (100 μM) or dimethyl sulfoxide (DMSO), as negative control, in a standard condition (RT: 37 and CO2: 5%). Cells were incubated (72 hours) and then examined for the cytometric evaluation of chemokine receptor CXCR3 expression on Th1 cells. Peripheral blood lymphocyte subpopulations were identified and evaluated by two color flow cytometric analysis. A nonparametric paired samples Wilcoxon test was applied to compare the grouped data. Results were expressed as the mean ± standard deviation (SD). P-values < 0·05 were considered to indicate significant differences. Findings: PBMCs treated with silymarin increased the expression of CXCR3 on Th1 cells. These results were significantly (P = 0.017) in all samples. Conclusion: This study provided evidences of effectiveness for silymarine on the expression of CXCR3. Therefore, in future, silymarine could be used instead of other drugs such as immunosuppressive with fewer side effects in autoimmune diseases.