The impact of omega-3 fatty acids on lung histopathology in mice model of chronic asthma

Abstract

 We aimed to determine the impact of the diet enriched with omega 3 fatty acids, a potential anti-inflammatory agent, on chronic changes of asthma in a mice model. Therapeutic modalities have not yet been proved to be successful in reversing alreadyestablished chronic changes of airways in asthma. For this reason, interventions including dietary changes before the sensitization and remodeling period would prevent those changes. Six-week old female Balb/c mice (n=18) were divided into two groups. During the development of chronic asthma model, mice in omega-3 fatty acid group received a diet enriched with omega-3 fatty acids, whereas mice in the other group received a diet with saturated fatty acids. Balb/c mice were sensitized intraperitoneally in both groups using 10 μg/100 μl of ovalbumin (OVA) and 1.5 mg Al (OH)3 on days 1, 14 and 21. Primed mice were challenged by repeated intranasal instillation of 20 μg/10 μl OVA three times a week. Mice were sacrificed and bronchoalveolar lavage fluid was obtained 24 h after the last challenge (day 77). The lungs were removed for histological examination. The omega-3 fatty acid group showed significantly reduced neutrophil percentage in bronchoalveolar lavage fluid. There was no statistically significant difference between the two groups in lymphocyte, macrophage and eosinophil percentages. The mean basement membrane thickness was less severe in the omega-3 group than the saturated fatty acid group. There was no significant difference between the two groups for goblet cell numbers, subepithelial smooth muscle of airways, and bronchial-associated lymphoid tissue. The findings of this study suggest that consumption of omega-3 fatty acids would prevent some of the chronic changes of airways due to asthma. Future studies are needed to evaluate the potential preventive and therapeutic effects of omega-3 fatty acids in asthma.

Keywords

• Asthma
• Experimental asthma
• Mice model
• Omega-3 fatty acids

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