Protective effect of silymarin during coronary artery bypass grafting surgery.

Background: An inflammatory response and systemic oxidative stress are directly caused by coronary artery bypass grafting (CABG) surgery. Cytokines, such as interleukin (IL) 1β, IL-6 and tumour necrosis factor-α (TNF-α), can also be stimulated. Reducing the release of pro-inflammatory cytokines plays an important role in limiting the postoperative inflammatory response. Silymarin has strong anti-inflammatory, antioxidant and cytoprotective properties.

Objective: To investigate the protective anti-inflammatory and antioxidant properties of silymarin against the inflammation and oxidative stresss inherent to CABG surgery.

Methods: Of the 102 patients undergoing elective first-time CABG surgery that were recruited, 50 (49.02%) received silymarin treatment and 52 (50.9%) were controls. Plasma cytokine levels (IL-1β, IL-6 and TNF-α) were measured preoperatively, 6 h and 24 h after CABG surgery. C-reactive protein (CRP) levels, trolox equivalent antioxidant capacity (TEAC) and glutathione (GSH) and malondialdehyde (MDA) levels were analyzed.

Results: Postoperative cytokine levels in the silymarin group were significantly lower compared with preoperative levels, and were significantly lower compared with postoperative control group levels. The area under the curve for cytokines and CRP for the silymarin group were significantly lower compared with preoperative levels, and were significantly lower compared with postoperative control group levels. Postoperative levels of TEAC and MDA in the silymarin-treated group were significantly lower than in the control group. GSH levels were significantly elevated in the silymarin group compared with control. No side effects or mortality were associated with the use of silymarin.

Conclusion: The anti-inflammatory and antioxidant effects of silymarin treatment provided protection against reperfusion injury and inflammation after CABG surgery.