Nigella sativa, a traditional Tunisian herbal medicine, attenuates bleomycin-induced pulmonary fibrosis in a rat model

Abstract The present study investigated the effects of Nigella sativa oil (NSO) on bleomycin (BLM)-induced lung fibrosis in rats. The rat model of pulmonary fibrosis (PF) was established by intratracheal instillation of BLM, and the effect of 1 ml/kg oral NSO treatment once daily observed. The effect of NSO was studied over a period of 50 days using 1 H RMN analysis on the urine and broncho alveolar lavage fluid (Balf) of the rats. Histopathological (inflammation and fibrosis) and immunohistochemical (TGF-β1 density) changes were evaluated. Results found that the BLM group showed a significant increase in inflammatory index (II), fibrosis score (FS) and TGF-β1 distribution in the lung inflammatory infiltrate, accompanied by a decreased urinary secretion of Krebs cycle intermediates, including acetate, pyruvate, carnitine, trimethylamine-N-oxide and succinate. However, at the same time point, NSO treated rats had a reduced II and FS, and had an increased urinary secretion of histidine, fumarate, allantoin and malate. In conclusion, NSO treatment attenuated the effects of BLM-induced PF, by supporting lung, liver and kidney activity in resisting PF. These findings provide an insight into the preventive and therapeutic potential of NSO in the treatment of PF.