Does tamoxifen citrate prevent pulmonary fi brosis due to silica inhalation?

Abstract

BACKGROUND: As shown in several studies, besides being used in breast cancer, tamoxifen is also known for its antifi brotic effects via reducing the serum TGF-beta levels. We investigated the possible preventive effect of tamoxifen in rats exposed to silica particles depending on the antifi brotic effect. MATERIALS AND METHODS: A total of 102 adult female Wistar Albino rats were divided into fi ve groups. First two groups (control and tmx) were free of silica and the last three groups (slc, tmx1 and tmx 10) were exposed to crystalline silica. The rats in tmx, tmx1 and tmx10 groups received 10 mg/kg, 1 mg/kg and 10 mg/kg of body weight tamoxifen, respectively. On day 84, all rats were sacrifi ed and tissue samples were obtained together with blood samples. The differences in serum TGF-β levels, histological grades of fi brosis and infl ammation in the lung and liver tissues together with addional biochemical markers were calculated between the groups. RESULTS: Silicosis occurred in slc, tmx1 and tmx10 groups in 100 %, 91.7 % and 52.1 %, respectively. Liver fi brosis did not occur. The highest mean lung fi brosis scores were obtained in slc group while the scores were lower in tmx1 group and the lowest in tmx10 within silica-exposed rats. Nevertheless, the infl ammation scores were higher in tamoxifen-administered rats in a dose-dependent pattern. CONCLUSION: Silica inhalation did not result in liver fi brosis. Tamoxifen is found to prevent lung fi brosis and reduce serum TGFβ-1 levels while increasing lung infl ammation (Tab. 3, Fig. 3, Ref. 27).