TY - JOUR
T1 - Heterologous regulation of anion transporters by menthol in human airway epithelial cells
AU - Morise, Masahiro
AU - Ito, Yasushi
AU - Matsuno, Tadakatsu
AU - Hibino, Yoshitaka
AU - Mizutani, Takefumi
AU - Ito, Satoru
AU - Hashimoto, Naozumi
AU - Kondo, Masashi
AU - Imaizumi, Kazuyoshi
AU - Hasegawa, Yoshinori
PY - 2010/6
Y1 - 2010/6
N2 - The present study concerns previously unreported effects of menthol, a cyclic terpene alcohol produced by the peppermint herb, on anion transporters in polarized human airway Calu-3 epithelia. Application of menthol (0.01-1mM) attenuated transepithelial anion transport, estimated as short-circuit currents (ISC), after stimulation by forskolin (10μM) but not before. In contrast, menthol potentiated forskolin-stimulated and -unstimulated apical Cl- conductance, which reflected the cystic fibrosis transmembrane conductance regulator (CFTR: the cAMP-regulated Cl- channel)-mediated conductance, without correlation to changes in cytosolic cAMP levels. These results indicate that menthol-induced attenuation of forskolin-induced ISC despite CFTR up-regulation was due to cAMP-independent inhibition of basolateral anion uptake, which is the rate-limiting step for transepithelial anion transport. Analyses of the responsible basolateral anion transporters revealed that forskolin increased both bumetanide (an inhibitor of the basolateral Na+-K+-2Cl- cotransporter [NKCC1])- and DNDS (an inhibitor of basolateral HCO3--dependent anion transporters [NBC1/AE2])-sensitive ISC in the control whereas only the former was prevented by the application of menthol. Neither the bumetanide- nor DNDS-sensitive component was, however, reduced by menthol without forskolin. These heterologous effects of menthol were reproduced by latrunculin B, an inhibitor of actin polymerization. F-actin staining showed that menthol prevented forskolin-stimulated rearrangements of actin microfilaments without affecting the distribution of forskolin-unstimulated microfilaments. Collectively, menthol functions as an activator of CFTR and prevents activation of NKCC1 without affecting NBC1/AE although all of these transporters are commonly cAMP-dependent. The heterologous effects may be mediated by the actin cytoskeleton, which interacts with CFTR and NKCC1.
AB - The present study concerns previously unreported effects of menthol, a cyclic terpene alcohol produced by the peppermint herb, on anion transporters in polarized human airway Calu-3 epithelia. Application of menthol (0.01-1mM) attenuated transepithelial anion transport, estimated as short-circuit currents (ISC), after stimulation by forskolin (10μM) but not before. In contrast, menthol potentiated forskolin-stimulated and -unstimulated apical Cl- conductance, which reflected the cystic fibrosis transmembrane conductance regulator (CFTR: the cAMP-regulated Cl- channel)-mediated conductance, without correlation to changes in cytosolic cAMP levels. These results indicate that menthol-induced attenuation of forskolin-induced ISC despite CFTR up-regulation was due to cAMP-independent inhibition of basolateral anion uptake, which is the rate-limiting step for transepithelial anion transport. Analyses of the responsible basolateral anion transporters revealed that forskolin increased both bumetanide (an inhibitor of the basolateral Na+-K+-2Cl- cotransporter [NKCC1])- and DNDS (an inhibitor of basolateral HCO3--dependent anion transporters [NBC1/AE2])-sensitive ISC in the control whereas only the former was prevented by the application of menthol. Neither the bumetanide- nor DNDS-sensitive component was, however, reduced by menthol without forskolin. These heterologous effects of menthol were reproduced by latrunculin B, an inhibitor of actin polymerization. F-actin staining showed that menthol prevented forskolin-stimulated rearrangements of actin microfilaments without affecting the distribution of forskolin-unstimulated microfilaments. Collectively, menthol functions as an activator of CFTR and prevents activation of NKCC1 without affecting NBC1/AE although all of these transporters are commonly cAMP-dependent. The heterologous effects may be mediated by the actin cytoskeleton, which interacts with CFTR and NKCC1.
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U2 - 10.1016/j.ejphar.2010.03.032
DO - 10.1016/j.ejphar.2010.03.032
M3 - Article
C2 - 20362570
AN - SCOPUS:77952321233
SN - 0014-2999
VL - 635
SP - 204
EP - 211
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
IS - 1-3
ER -