Kiwifruit with high anthocyanin content modulates NF-κB activation and reduces CCL11 secretion in human alveolar epithelial cells

Asthma is an allergic lung inflammation characterised by the influx of eosinophils at the infected site recruited by the chemokine, CCL11. During inflammation, the transcription factor Nuclear Factor kappa B (NF-κB) initiates a series of pro-inflammatory responses. Natural compounds that could modulate CCL11 levels and/or NF-κB activation have potential for managing lung inflammation. In this study, four varieties of kiwifruit were evaluated for their modulatory effect on inflammation signals. The anthocyanin-enriched polyphenol extracts from purple kiwifruit inhibited CCL11 secretion from human alveolar epithelial cells whereas the anthocyanin-lacking polyphenol extracts from yellow kiwifruit displayed no inhibition on CCL11 secretion. Kiwifruit polyphenol extracts also inhibited NF-κB activation in reporter cells. Correlation analysis showed anthocyanins in the kiwifruit polyphenolic extracts were most correlated to the modulation of CCL11 and NF-κB which are the inflammatory signals involved in lung allergic inflammation. The findings highlight the enhanced functional food benefits of novel kiwifruit cultivars.