The possible protective role of broccoli extract against acute pulmonary toxicity induced by nicotine and/or γ-irradiation in rats

Abstract The current research design investigates the potential ameliorative role of broccoli extract against rat pulmonary toxicity produced by nicotine and/or γ-ray exposure in rats. While individual components of broccoli have shown protective effects against either nicotine or radiation separately, the efficacy of whole broccoli extract against concurrent exposure to both agents have not been previously investigated. These findings suggested that the antioxidant activities of broccoli extract are mediated through phenol and flavonoid contents. Broccoli extract has yielded many compounds such as fatty acids, alcohols, esters, and aldehydes identified using GC-MS assay, which exhibited biological activities. The protective role of the broccoli extract against γ-ray- and/or nicotine-induced rat lung toxicity was estimated. A total of 48 rats were categorized into eight groups: control, broccoli (300 mg/kg B.W.), nicotine (4 mg/kg B.W.), γ-ray (8.5 Gy), nicotine + γ-ray, broccoli + nicotine, broccoli + γ -ray, and broccoli + nicotine + γ-ray. The pulmonary tissues were harvested for biochemical and histopathological studies. Pulmonary toxicity was assessed using key biomarkers: hydroxyproline for fibrosis, malondialdehyde (MDA) for lipid peroxidation, superoxide dismutase (SOD) and GPX for antioxidant capacity, and tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) for inflammation markers, alongside histopathological examination. Exposure to nicotine or γ-rays significantly elevated hydroxyproline, MDA, TNF-α, & IL-6 levels while lowering SOD activity ( p < 0.0001), indicating fibrosis, oxidative stress, and inflammation. The combined nicotine + γ-ray group exhibited the most severe effects. Broccoli extract therapy considerably ameliorated these alterations, returning biomarkers to nearly control levels and improved histopathology results. In conclusion, this preclinical study the broccoli extract attenuates nicotine- and radiation-induced pulmonary toxicity through anti-fibrotic, antioxidant, and anti-inflammatory mechanisms, implying that it may be beneficial as a protective treatment for radiotherapy patients, particularly those with a history of smoking, but direct translation to human application is not yet warranted.