Differential cytotoxicity and intracellular calcium-signalling following activation of the calcium-permeable ion channels TRPV1 and TRPA1. (December 2017)

• Record Type: Journal Article
• Authors: Stueber, Thomas; Eberhardt, Mirjam J.; Caspi, Yaki; Lev, Shaya; Binshtok, Alexander; Leffler, Andreas
• Is Part Of: Cell calcium. Volume 68(2017)
• Page Start: 34
• Page End: 44
• Publication Date: 2017-12
• Subjects: DRG dorsal root ganglion neuron -- TRP transient receptor potential -- ER endoplasmic reticulum -- AITC allyl isothiocyanate -- HEK human embryonic kidney -- BCTC 4-(3-Chloro-2-pyridinyl)-N-[4-(1, 1-dimethylethyl)phenyl]-1-piperazinecarboxamide -- BABTA 1, 2-Bis(2-aminophenoxy)ethane-N, N, N′, N′-tetraacetic acid tetrakis; TRP channel -- Intracellular calcium -- Cell death -- Endoplasmic reticulum -- Sensory neurons -- Mitochondria; Calcium -- Metabolism -- Periodicals; Vertebrates -- Physiology -- Periodicals; Calcium -- Physiological effect -- Periodicals; Cell physiology -- Periodicals; Calcium in the body -- Periodicals; 572.516
• DOI: 10.1016/j.ceca.2017.10.003
• Languages: English
• ISSNs: 0143-4160

Abstract

Graphical abstract: Highlights: In contrast to TRPV1, activation of TRPA1 does not trigger cell death. Both TRPA1 and TRPV1 are functionally expressed in the endoplasmic reticulum. Activation of TRPV1, but not TRPA1 results in a strong increase of mitochondrial calcium. Abstract: Several members of the transient receptor channel (TRP) family can mediate a calcium-dependent cytotoxicity. In sensory neurons, vanilloids like capsaicin induce neurotoxicity by activating TRPV1. The closely related ion channel TRPA1 is also activated by irritants, but it is unclear if and how TRPA1 mediates cell death. In the present study we explored cytotoxicity and intracellular calcium signalling resulting from activation of TRPV1 and TRPA1, either heterologously expressed in HEK 293 cells or in native mouse dorsal root ganglion (DRG) neurons. While activation of TRPV1 by the vanilloids capsaicin, resiniferatoxin and anandamide results in calcium-dependent cell death, activation by protons and the oxidant chloramine-T failed to reduce cell viability. The TRPA1-agonists acrolein, carvacrol and capsazepine all induced cytotoxicity, but this effect is independent of TRPA1. Activation of both TRPA1 and TRPV1 triggers a strong influx of external calcium, but also a strong calcium-release from intracellular stores most likely including the endoplasmic reticulum (ER). Activation of TRPV1, but not TRPA1 also results in a strong increase of mitochondrial calcium both in HEK 293 cells and mouse DRG neurons. Our data demonstrate that activation of TRPV1, but not TRPA1 mediates a calcium-dependent cell death. While both receptors mediate a release of calcium from intracellular stores, only activation of TRPV1 seems to mediate a robust and probably lethal increase in mitochondrial calcium.