Introduction: Bisphenol A (BPA), is known to be extensively utilized industrial chemical for manufacturing many products. It has a toxic, cumulative effect on human health. Propolis is a natural product with anti-inflammatory, anti-oxidant and anti-cytotoxic activities. Objective: To study the effect of BPA exposure on adult male albino rats lung and to evaluate the possible protective role of propolis. Material and Methods: Forty-five adult male albino rats were divided into four groups: Group I: control. Group II (BPA treated group): received BPA (500 mg/kg) for 8 weeks. Group III (recovery): received BPA as group II then left for 2 weeks without treatment for recovery. Group IV (Propolis and BPA treated group): received propolis at a dose of (50 mg/kg) and Bisphenol A (500mg/kg) for 8 weeks. All doses were given orally by gastric tube once daily. At assigned time of sacrifice, rats were anaesthetized and lung specimens were dissected and processed for biochemical, histological, immunohistochemical and ultrastructural studies.
Results: Bisphenol A caused alveolar collapse, distorted bronchiolar mucosa, inflammatory cellular infiltration and congested thickened blood vessels. By E/M; pneumocytes type II showed shrunken nuclei, empty lamellar bodies, and degenerated mitochondria. Oxidative stress markers showed significant increase of malondialdehyde (MDA) levels of groups II and III and significant decrease of superoxide dismutase (SOD) and reduced glutathione (GSH) levels compared to control group. Thickness of the interalveolar septum, area percentage of collagen fibers and number of positive (CD68) macrophages increased significantly with groups II and III compared with the control group. However, area percentage of B- cell lymphocyte-2 (BCL2) reactivity was reduced. The use of propolis improved these changes.
Conclusion: BPA exposure induced structural changes in the rat lung. These changes could be minimized by concomitant administration of propolis. So propolis is recommended to be used as a protective agent.