International Journal of COPD (Feb 2016)
Antioxidant activity of pomegranate juice reduces emphysematous changes and injury secondary to cigarette smoke in an animal model and human alveolar cells
Abstract
Ahmad Husari,1,* Yasmine Hashem,1 Hala Bitar,1 Ghassan Dbaibo,2,3 Ghazi Zaatari,4 Marwan El Sabban5,* 1Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, 2Department of Pediatrics and Adolescent Medicine, Division of Pediatric Infectious Diseases, 3Department of Biochemistry and Molecular Genetics, 4Department of Pathology and Laboratory Medicine, 5Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon *These authors contributed equally to this work Background: Cigarette smoke (CS) increases oxidative stress (OS) in the lungs. Pomegranate juice (PJ) possesses potent antioxidant activities, attributed to its polyphenols. This study investigates the effects of PJ on the damaging effects of CS in an animal model and on cultured human alveolar cells (A549). Methods: Male C57BL/6J mice were divided into the following groups: Control, CS, CS + PJ, and PJ. Acute CS exposure was for 3 days, while chronic exposure was for 1 and 3 months (5 days of exposure/week). PJ groups received daily 80 µmol/kg via bottle, while other groups received distilled water. At the end of the experiments, different parameters were studied: 1) expression levels of inflammatory markers, 2) apoptosis, 3) OS, and 4) histopathological changes. In vitro, A549 cells were pretreated for 48 hours with either PJ (0.5 µM) or vehicle. Cells were then exposed to increasing concentrations of CS extracted from collected filters. Cell viability was assessed by counting of live and dead cells with trypan blue staining. Results: Acutely, a significant increase in interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α expression, apoptosis, and OS was noted in CS when compared to Control. PJ significantly attenuated the expression of inflammatory mediators, apoptosis, and OS. Chronically (at 1 and 3 months), increased expression of TNF-α was observed, and lung sections demonstrated emphysematous changes when compared to Control. PJ supplementation to CS animals attenuated the increased expression of TNF-α and normalized lung cytoarchitecture. At the cellular level, CS extract reduced cellular proliferation and triggered cellular death. Pretreatment with PJ attenuated the damaging effects of CS extract on cultured human alveolar cells. Conclusion: The expression of inflammatory mediators associated with CS exposure and the emphysematous changes noted with chronic CS exposure were reduced with PJ supplementation. In vitro, PJ attenuated the damaging effects of CS extract on cultured human alveolar cells. Keywords: reactive oxygen species, antioxidants, acute lung injury, emphysema, pomegranate extract, cigarette smoke, inflammatory mediators