The Protective Impact of Aqueous Ginger Extract on Oxidative Stress and Inflammation of the Male Rats’ Lungs Exposed to Cigarette Smoke

Smoking is a main contributor to lung pathogenesis, inflammation, oxidative stress and structural changes. This study aimed to investigate the impact of cigarette smoke on lung tissue and to explore the potential benefit of ginger extracts in rats. Four groups of male rats were employed to achieve this goal. The first group was considered a control group and three experimental groups. The second group was fed with ginger extract (250 mg/kg/day); the third group was exposed to cigarette smoke, while the fourth group was fed with ginger (250 mg/kg/day) and exposed to cigarette smoke. Eighteen cigarettes were ignited twice daily for 4 months. Subsequently, the tumour necrosis factor‐alpha (TNF‐α) and α‐fetoprotein (α‐FP) levels, along with the parameters of inflammatory cytokines, oxidative stress, antioxidant activity and lung histopathology, were analysed. The animals in the third group showed a significant increase ( p < 0.05) of TNF‐α, a‐FP and interleukin (IL‐2 and IL‐1β) levels, along with a notable decrease in anti‐inflammatory cytokine (IL‐22). Oxidative stress parameters, including xanthine oxidase (XOD), myeloperoxidase (MPO) and malondialdehyde (MDA), exhibited a significant increase ( p < 0.05) in the rats exposed to smoke, but decreased significantly in the second and fourth group of rats. Meanwhile, levels of antioxidant activity, including glutathione (GSH), superoxide dismutase (SOD) and total thiol, were significantly reduced ( p < 0.05) in the animals exposed to cigarette smoke but significantly elevated in the ginger‐treated groups (the second and fourth groups). The lungs of rats exposed to smoke also exhibited severe congestion with lung tissue inflammation. The results indicate that the ginger extract has protective impacts against adverse smoking effects, possibly due to its anti‐inflammatory and antioxidant properties, which lead to better regulation of oxidative stress, improving the antioxidant defence system, as well as reducing the pathological changes in lungs due to smoking.