背景:益康唑是一种广泛使用的咪唑衍生物抗真菌药,用于治疗皮肤感染。其频繁的不良反应的分子靶点为皮肤刺激症状,如瘙痒,灼烧感,和痛苦,尚未澄清。瞬时受体电位(TRP)通道,非选择性阳离子通道,主要在外周感觉神经元中表达,并作为各种刺激物的传感器。
方法:我们通过在从野生型分离的小鼠背根神经节(DRG)神经元中通过荧光比率成像测量细胞内钙浓度([Ca2]i),研究了益康唑对TRP通道激活的影响。TRPA1(-/-)和TRPV1(-/-)小鼠,以及在异源TRP通道表达的细胞中。面颊注射模型用于评估益康唑诱导的体内瘙痒和疼痛。
结果:益康唑引起[Ca2+]i增加,通过去除小鼠DRG神经元中的细胞外Ca2被废除。TRPA1阻断剂抑制了对益康唑的[Ca2]i反应,但TRPV1阻断剂未抑制。在TRPA1(-/-)小鼠DRG神经元中观察到益康唑诱导的[Ca2]i反应的减弱,但在TRPV1(-/-)神经元中没有显着。益康唑在表达TRPA1(TRPA1-HEK)的HEK293细胞中增加[Ca2]i,但在表达TRPV1的细胞中不增加,尽管浓度较高,它在未转染的初始HEK293细胞中诱导Ca2+从细胞内储存中动员。咪康唑,是益康唑的结构类似物,还增加了小鼠DRG神经元和TRPA1-HEK中的[Ca2]i,其非特异性作用大于益康唑。氟康唑,三唑类药物未能激活小鼠DRG神经元和TRPA1-HEK中的TRPA1和TRPV1。益康唑在野生型小鼠中引起瘙痒和疼痛,在TRPA1(-/-)小鼠中具有降低的应答。
结论:这些发现表明,咪唑衍生物益康唑和咪康唑可能通过激活感觉神经元的伤害性TRPA1而引起皮肤刺激。抑制TRPA1活化可以减轻益康唑的不良反应。
BACKGROUND: Econazole is a widely used imidazole derivative antifungal for treating skin infections. The molecular targets for its frequent adverse effects of skin irritation symptoms, such as pruritus, burning sensation, and pain, have not been clarified. Transient receptor potential (TRP) channels, non-selective cation channels, are mainly expressed in peripheral sensory neurons and serve as sensors for various irritants.
METHODS: We investigated the effect of econazole on TRP channel activation by measuring intracellular calcium concentration ([Ca2+]i) through fluorescent ratio imaging in mouse dorsal root ganglion (DRG) neurons isolated from wild-type, TRPA1(-/-) and TRPV1(-/-) mice, as well as in heterologously TRP channel-expressed cells. A cheek injection model was employed to assess econazole-induced itch and pain in vivo.
RESULTS: Econazole evoked an increase in [Ca2+]i, which was abolished by the removal of extracellular Ca2+ in mouse DRG neurons. The [Ca2+]i responses to econazole were suppressed by a TRPA1 blocker but not by a TRPV1 blocker. Attenuation of the econazole-induced [Ca2+]i responses was observed in the TRPA1(-/-) mouse DRG neurons but was not significant in the TRPV1(-/-) neurons. Econazole increased the [Ca2+]i in HEK293 cells expressing TRPA1 (TRPA1-HEK) but not in those expressing TRPV1, although at higher concentrations, it induced Ca2+ mobilization from intracellular stores in untransfected naïve HEK293 cells. Miconazole, which is a structural analog of econazole, also increased the [Ca2+]i in mouse DRG neurons and TRPA1-HEK, and its nonspecific action was larger than econazole. Fluconazole, a triazole drug failed to activate TRPA1 and TRPV1 in mouse DRG neurons and TRPA1-HEK. Econazole induced itch and pain in wild-type mice, with reduced responses in TRPA1(-/-) mice.
CONCLUSIONS: These findings suggested that the imidazole derivatives econazole and miconazole may induce skin irritation by activating nociceptive TRPA1 in the sensory neurons. Suppression of TRPA1 activation may mitigate the adverse effects of econazole.