British Journal of Nutrition

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British Journal of Nutrition (2010), 104:164-170 Cambridge University Press
Copyright © The Authors 2010
doi:10.1017/S0007114510000346

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Molecular Nutrition

Quercetin, the active phenolic component in kiwifruit, prevents hydrogen peroxide-induced inhibition of gap-junction intercellular communication


Dong Eun Leea1a2, Bong Jik Shina1, Haeng Jeon Hura1, Jong Hun Kima2, Jiyoung Kima1a2, Nam Joo Kanga1a2a3, Dae Ok Kima4, Chang Yong Leea5, Ki Won Leea2 c1 and Hyong Joo Leea1 c1

a1 Major in Biomodulation, WCU, Department of Agricultural Biotechnology, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea
a2 Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Republic of Korea
a3 School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Republic of Korea
a4 Department of Food Science and Technology, Kyung Hee University, Yongin, Republic of Korea
a5 Department of Food Science and Technology, Cornell University, Geneva, NY 14456, USA
Article author query
lee de [PubMed]  [Google Scholar]
shin bj [PubMed]  [Google Scholar]
hur hj [PubMed]  [Google Scholar]
kim jh [PubMed]  [Google Scholar]
kim j [PubMed]  [Google Scholar]
kang nj [PubMed]  [Google Scholar]
kim do [PubMed]  [Google Scholar]
lee cy [PubMed]  [Google Scholar]
lee kw [PubMed]  [Google Scholar]
lee hj [PubMed]  [Google Scholar]

Abstract

We evaluated the effects of the two main kiwifruit cultivars (gold kiwifruit (GOK) and green kiwifruit (GRK)) and their active phenolic compound, quercetin, on H2O2-induced inhibition of gap-junction intercellular communication (GJIC) in WB-F344 rat liver epithelial cells. We found that both GOK and GRK protect WB-F344 cells from H2O2-induced inhibition of GJIC. The extracellular signal-regulated protein kinase 1/2 (ERK1/2)–connexin 43 (Cx43) signalling pathway is crucial for the regulation of GJIC, and both GOK and GRK blocked the H2O2-induced phosphorylation of Cx43 and ERK1/2 in WB-F344 cells. Quercetin alone attenuated the H2O2-mediated ERK1/2–Cx43 signalling pathway and consequently reversed H2O2-mediated inhibition of GJIC in WB-F344 cells. A free radical-scavenging assay using 1,1-diphenyl-2-picrylhydrazyl showed that the scavenging activity of quercetin was higher than that of a synthetic antioxidant, butylated hydroxytoluene, per mol, suggesting that the chemopreventive effect of quercetin on H2O2-mediated inhibition of ERK1/2–Cx43 signalling and GJIC may be mediated through its free radical-scavenging activity. Since the carcinogenicity of reactive oxygen species such as H2O2 is attributable to the inhibition of GJIC, GOK, GRK and quercetin may have chemopreventive potential by preventing the inhibition of GJIC.

(Received August 10 2009)

(Revised December 11 2009)

(Accepted January 12 2010)

(Online publication March 22 2010)

Key Words:Connexin 43; Extracellular signal-regulated protein kinase 1/2; Gap-junction intercellular communication; Kiwifruit; Quercetin

Correspondence:

c1 Corresponding author: Dr Hyong Joo Lee, fax +82 2 873 5095, email leehyjo@snu.ac.kr; Dr Ki Won Lee, fax +82 2 3436 6178, email kiwon@konkuk.ac.kr

Footnotes

Abbreviations: BHT, butylated hydroxytoluene; Cx43, connexin 43; DPPH, 1,1-diphenyl-2-picrylhydrazyl; ERK1/2, extracellular signal-regulated protein kinase 1/2; GJIC, gap-junction intercellular communication; GOK, gold kiwifruit; GRK, green kiwifruit


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