Evaluation of protective effects of tannic acid/iron complex against lung fibrosis induced by bleomycin in rat

OBJECTIVE(S): Pulmonary fibrosis (PF) is a seriousand advancing respiratory condition that arises from various contributing factors. Bleomycin (BLM) is a chemotherapeutic drug known to cause different side effects, including PF. The current study aimed to assess the protective effects of the Tannic Acid/Iron complex (TAIC) against PF induced by BLM in a rat model. MATERIALS AND METHODS: PF was induced in Wistar rats by a single dose of BLM (7.5 U/kg) on the 7th day. The rats were then randomly assigned to six groups: control, BLM, and four treatment groups receiving BLM + different doses of TAIC or TA alone (28 days, gavage). Animals were sacrificed on the 29th day and lung samples were collected to assess histopathological alterations and biochemical parameters such as lung index, nitric oxide (NO), malondialdehyde (MDA), hydroxyproline (HP), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and tumor necrosis factor- α (TNF-α). RESULTS: The results demonstrated that the TAIC complex significantly attenuated BLM-induced elevation in lung index as well as the levels of MDA, NO, HP, and TNF-α. Additionally, TAIC enhanced the activities of key antioxidant enzymes, including CAT, SOD, GPx, and increased GSH content. This complex also inhibited the infiltration of fibroblasts and inflammatory cells, thereby preventing alveolar thickening. Notably, the effect of TA at 400 mg/kg, while beneficial, was slightly less pronounced compared to the TAIC complex at the same dosage. CONCLUSION: The results revealed that TAIC hasa protective effect on BLM -induced pulmonary fibrosis.