TY - JOUR
T1 - Comparative analysis of allyl isothiocyanate (AITC)-induced carbohydrate oxidation changes via TRPV1 between mice and chickens
AU - Kawabata, Fuminori
AU - Kawabata, Yuko
AU - Liang, Ruojun
AU - Nishimura, Shotaro
AU - Tabata, Shoji
N1 - Funding Information:
We thank Mr. Zhen Zhu for collecting data of respiratory gas analysis. We appreciate the technical assistance of the Research Support Center, Research Center for Human Disease Modeling, Kyushu University Graduate School of Medical Sciences. This study was supported in part by a grant to F.K. from the Funds for the Development of Human Resources in Science and Technology, the Japan Science and Technology Agency. This work was also supported by a grant to F.K. from the Urakami Foundation (Tokyo). We thank Professor Makoto Tominaga and Dr. Shigeru Saito (Okazaki Institute for Integrative Bioscience) for providing the cTRPV1 and mTRPV1 constructs, and Dr. Koji Shibasaki (Gunma University) for providing the EGFP construct.
Publisher Copyright:
© 2017, Biomedical Research Foundation. All rights reserved.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2017
Y1 - 2017
N2 - Postprandial hyperglycemia is a risk factor for cardiovascular diseases. It has been reported that intragastric administration of allyl isothiocyanate (AITC), which is one of the pungent ingredients of wasabi and horseradish but it is not included in hot chili pepper, increased carbohydrate oxidation and reduced postprandial increase of blood glucose via transient receptor potential vanilloid 1 (TRPV1) in mice. However, the action site of AITC on TRPV1 for increasing carbohydrate oxidation is unclear. Both mammalian and chicken TRPV1 (cTRPV1) are activated by heat and acid, but unlike its mammalian counterpart, cTRPV1 is only faintly activated by capsaicin. This difference is due to the 8 chicken-specific amino acid residues around transmembrane 3, which is the main site of capsaicin-binding in rat TRPV1. Moreover, AITC-induced activation of mouse TRPV1 (mTRPV1) is largely dependent on S513, a residue that is involved in capsaicin-binding. Thus, we hypothesized that the increase of carbohydrate oxidation by AITC in mammals is induced by the binding of AITC to the capsaicin-binding site of TRPV1. In this study, we performed a comparative study using chickens and mice, since chickens are thought to partly lack the capsaicin-binding site of TRPV1. We examined the effects of AITC on the respiratory quotient (RQ), the index of carbohydrate oxidation and fat oxidation, in chickens and mice. Respiratory gas analysis revealed that AITC does not increase the RQ in chickens, and Ca2+ imaging methods and a whole cell-patch clamp analysis showed that AITC does not activate cTRPV1. These results implied that the capsaicin-binding site is an important region for increasing carbohydrate oxidation by AITC administration in animals.
AB - Postprandial hyperglycemia is a risk factor for cardiovascular diseases. It has been reported that intragastric administration of allyl isothiocyanate (AITC), which is one of the pungent ingredients of wasabi and horseradish but it is not included in hot chili pepper, increased carbohydrate oxidation and reduced postprandial increase of blood glucose via transient receptor potential vanilloid 1 (TRPV1) in mice. However, the action site of AITC on TRPV1 for increasing carbohydrate oxidation is unclear. Both mammalian and chicken TRPV1 (cTRPV1) are activated by heat and acid, but unlike its mammalian counterpart, cTRPV1 is only faintly activated by capsaicin. This difference is due to the 8 chicken-specific amino acid residues around transmembrane 3, which is the main site of capsaicin-binding in rat TRPV1. Moreover, AITC-induced activation of mouse TRPV1 (mTRPV1) is largely dependent on S513, a residue that is involved in capsaicin-binding. Thus, we hypothesized that the increase of carbohydrate oxidation by AITC in mammals is induced by the binding of AITC to the capsaicin-binding site of TRPV1. In this study, we performed a comparative study using chickens and mice, since chickens are thought to partly lack the capsaicin-binding site of TRPV1. We examined the effects of AITC on the respiratory quotient (RQ), the index of carbohydrate oxidation and fat oxidation, in chickens and mice. Respiratory gas analysis revealed that AITC does not increase the RQ in chickens, and Ca2+ imaging methods and a whole cell-patch clamp analysis showed that AITC does not activate cTRPV1. These results implied that the capsaicin-binding site is an important region for increasing carbohydrate oxidation by AITC administration in animals.
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U2 - 10.2220/biomedres.38.149
DO - 10.2220/biomedres.38.149
M3 - Article
C2 - 28637949
AN - SCOPUS:85021086255
VL - 38
SP - 149
EP - 155
JO - Biomedical Research
JF - Biomedical Research
SN - 0388-6107
IS - 3
ER -