PDF(Pubmed)
Abstract：
Clodronate (Clod), a first-generation bisphosphonate, acts as a natural analgesic inhibiting vesicular storage of the nociception mediator ATP by vesicular nucleotide transporter (VNUT). Epidermal keratinocytes participate in cutaneous nociception, accumulating ATP within vesicles, which are released following different stimulations. Under stress conditions, keratinocytes produce microvesicles (MVs) by shedding from plasma membrane evagination. MV secretion has been identified as a novel and universal mode of intercellular communication between cells. The aim of this project was to evaluate if two nociceptive stimuli, Capsaicin and Potassium Hydroxide (KOH), could stimulate MV shedding from human keratinocytes, if these MVs could contain ATP, and if Clod could inhibit this phenomenon. In our cellular model, the HaCaT keratinocyte monolayer, both Capsaicin and KOH stimulated MV release after 3 h incubation, and the released MVs contained ATP. Moreover, Clod (5 µM) was able to reduce Caps-induced MV release and abolish the one KOH induced, while the Dansylcadaverine, an endocytosis inhibitor of Clod uptake, partially failed to block the bisphosphonate activity. Based on these new data and given the role of the activation of ATP release by keratinocytes as a vehicle for nociception and pain, the \"old\" bisphosphonate Clodronate could provide the pharmacological basis to develop new local analgesic drugs.
摘要：
氯膦酸盐(Clod),第一代双膦酸盐，通过囊泡核苷酸转运蛋白（VNUT）作为天然止痛药，抑制伤害感受介质ATP的囊泡储存。表皮角质形成细胞参与皮肤伤害感受，在囊泡内积累ATP，在不同的刺激下释放。在应力条件下，角质形成细胞通过从质膜逃逸脱落而产生微泡（MV）。MV分泌已被鉴定为细胞间细胞间通讯的一种新颖且通用的模式。该项目的目的是评估两种伤害性刺激是否，辣椒素和氢氧化钾（KOH），可以刺激人角质形成细胞的MV脱落，如果这些MV可能含有ATP，如果Clod能抑制这种现象.在我们的细胞模型中，HaCaT角质形成细胞单层，辣椒素和KOH在3小时孵育后刺激MV释放，释放的MV含有ATP。此外，Clod（5µM）能够减少Caps诱导的MV释放并消除KOH诱导的MV释放，而丹西尸胺，一种Clod摄取的内吞作用抑制剂，部分未能阻断双膦酸盐活性。基于这些新数据，并考虑到角质形成细胞激活ATP释放作为伤害感受和疼痛的载体的作用，“旧的”双膦酸盐氯膦酸盐可以为开发新的局部镇痛药物提供药理基础。
