Antiadhesive and anti-inflammatory effects of pirfenidone in postoperative intra-abdominal adhesion in an experimental rat model.

Background: Pirfenidone (PF) is a potent antifibrotic and anti-inflammatory agent. We investigated the protective effect of PF against postoperative intra-abdominal adhesions.

Material And Methods: Thirty male Sprague-Dawley rats were divided into three groups (n = 10 in each group). In group 1 (control), adhesion induction was performed by cecal abrasion, and no treatment was administered. In group 2 (vehicle), for 2 wk after adhesion induction, 0.4%-carboxymethylcellulose was administered by gavage. In group 3 (PF treatment), for 2 wk after adhesion induction, 500-mg/kg/d PF was administered by gavage. On the 15th postoperative day, the animals were killed, and cecal and peritoneal tissues were excised. The adhesions were graded macroscopically. The protein concentrations and mRNA expression levels of the following genes were measured in the tissues: matrix metallopeptidase-9 (MMP-9); tissue inhibitor of metalloproteinase-1 (TIMP-1); tumor necrosis factor-alpha (TNF-α); and transforming growth factor-beta 1 (TGF-β1). The tissue samples were also evaluated histopathologically.

Results: Macroscopic and histopathologic evaluation showed that PF-reduced adhesion and inflammation (P < 0.001, P = 0.004, respectively). Pretreatment with PF-reduced TIMP-1, TNF-α, and TGF-β1 protein concentrations (P < 0.001, P < 0.001, and P < 0.001, respectively) and mRNA expression levels (P = 0.030, P = 0.005, and P = 0.016, respectively) and increased MMP-9 protein concentrations (P < 0.001) and mRNA expression (P = 0.021).

Conclusions: The findings of this study suggest that PF can be used as a protective agent to prevent the development of peritoneal adhesions and inflammation during the postoperative period.