Goishi tea consumption inhibits airway hyperresponsiveness in BALB/c mice

Ryoji Hirota,Mitsuhiko Miyamura,Narufumi Suganuma,Hiroyuki Nakamura,Nlandu R Ngatu

doi:10.1186/1471-2172-12-45

Ryoji Hirota, Mitsuhiko Miyamura + Show 3 more

Open Access

https://doi.org/10.1186/1471-2172-12-45

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Abstract

BackgroundAirway hyperresponsiveness (AHR) is one of the important traits that characterize bronchial asthma. Goishi tea is a post-heating fermented tea that has been reported to have higher free radical scavenging activity. In this study, we evaluated the prophylactic effects of Goishi tea on AHR in BALB/c mice.ResultsThe number of inflammatory cells in BAL fluid was considerably reduced in Goishi tea/Der f and Gallic acid/Der f groups as compared with Tap water/Der f group. Regarding inflammatory cells in BAL, a significant reduction of eosinophils and neutrophils was observed in Goishi tea-treated mice (p < 0.01), as well as in the Gallic acid/Der f group (p < 0.05), as compared with Tap water/Der f group. In asthmatic mice (Tap water/Der f group), the intensity of airway resistance increased simultaneously with the increase in acetylcholine concentration in a dose-dependant way. AHR was significantly inhibited in Goishi tea/Der f and Gallic acid/Der f (p < 0.01) groups as compared with the Tap water/Der f group. Regarding serum specific-IgG1, significantly lower levels of this antibody were observed in Goishi tea/Der f and Gallic acid/Der f groups as compared with the Tap water/Der f group (p < 0.05). In addition, adiponectin level was significantly higher in the Goishi tea group as compared with the Tap water treated mice (p < 0.01).ConclusionsThe results suggest that Goishi tea consumption exerted an inhibitory effect on eosinophilic and neutrophilic infiltration in the lung, attenuated the increase in airway resistance and increased the production of adiponectin; thus reducing Der f induced allergic inflammatory process in mice.

Highlights

Airway hyperresponsiveness (AHR) is one of the important traits that characterize bronchial asthma
The number of macrophages was lower in the Goishi tea/Dermatophagoides farinaeplus (Der f) group than in the asthmatic mice (Tap water/Der f group), the difference was not significant
Goishi tea consumption attenuates AHR Repeated challenges to mice lung with ACh induced AHR in Tap water/Der f mice in a dose-dependent way

Summary

Introduction

Airway hyperresponsiveness (AHR) is one of the important traits that characterize bronchial asthma. Goishi tea is a post-heating fermented tea that has been reported to have higher free radical scavenging activity. We evaluated the prophylactic effects of Goishi tea on AHR in BALB/c mice. Airway hyperresponsiveness (AHR) is one of the important traits that characterize bronchial asthma, apart from eosinophilic infiltration, reversible airway narrowing and chronic inflammation [1,2]. Epigallocatechin gallate (EGCG) and catechin from green tea, for example, have been reported to improve cardiovascular function, increase fat oxidation in mice and exert free radicals and reactive oxygen species (ROS) scavenging activity [3,4,5,6,7]. Green tea is processed as follows: harvested Camellia sinensis leaves are heated rubbed and they are dried. There are few publications on Goishi tea and very little is known about its bioactive properties

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