The transient receptor potential ion channel TRPM3 is highly prevalent on nociceptive dorsal root ganglion (DRG) neurons, but its functions in neuronal plasticity of chronic pain remain obscure. In an animal model of nonspecific low back pain (LBP), latent spinal sensitization known as nociceptive priming is induced by nerve growth factor (NGF) injection. Here, we address the TRPM3-associated molecular basis of NGF-induced latent spinal sensitization at presynaptic level by studying TRPM3-mediated calcium transients in DRG neurons. By investigating TRPM3-expressing HEK cells, we further show the dynamic mitochondrial activity downstream of TRPM3 activation. NGF enhances TRPM3 function, attenuates TRPM3 tachyphylaxis, and slows intracellular calcium clearance; TRPM3 activation triggers more mitochondrial calcium loading than depolarization does, causing a steady-state mitochondrial calcium elevation and a delayed recovery of cytosolic calcium; mitochondrial calcium buffering accounts for approximately 40% of calcium influx subsequent to TRPM3 activation. TRPM3 activation provokes an outbreak of pulsatile superoxide production (mitoflash) that comes in the form of a surge in frequency being tunable. We suggest that mitoflash pulsations downstream of TRPM3 activation might be an early signaling event initiating pain sensitization. Tuning of mitoflash activity would be a novel bottom-up therapeutic strategy for chronic pain conditions such as LBP and beyond.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1097/j.pain.0000000000002642 | DOI Listing |
Ann Neurol
January 2025
Department of Pediatric Neurology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Objective: Monoallelic variants in the transient receptor potential melastatin-related type 3 gene (TRPM3) have been associated with neurodevelopmental manifestations, but knowledge on the clinical manifestations and treatment options is limited. We characterized the clinical spectrum, highlighting particularly the epilepsy phenotype, and the effect of treatments.
Methods: We analyzed retrospectively the phenotypes and genotypes of 43 individuals with TRPM3 variants, acquired from GeneMatcher and collaborations (n = 21), and through a systematic literature search (n = 22).
Front Pharmacol
December 2024
Institute of Pharmacology and Clinical Pharmacy, Goethe University Frankfurt, Frankfurt, Germany.
Mol Metab
December 2024
Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, University of Manitoba, Winnipeg, Canada; Department of Pharmacology and Therapeutics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada. Electronic address:
Objective: Antagonism of the muscarinic acetylcholine type 1 receptor (MR) promotes sensory axon repair and is protective in peripheral neuropathy, however, the mechanism remains elusive. We investigated the role of the heat-sensing transient receptor potential melastatin-3 (TRPM3) cation channel in MR antagonism-mediated nerve regeneration and explored the potential of TRPM3 activation to facilitate axonal plasticity.
Methods: Dorsal root ganglion (DRG) neurons from adult control or diabetic rats were cultured and treated with TRPM3 agonists (CIM0216, pregnenolone sulfate) and MR antagonists pirenzepine (PZ) or muscarinic toxin 7 (MT7).
Front Cell Dev Biol
November 2024
Department of Pharmacology and Pharmacotherapy, Medical School and Centre for Neuroscience, University of Pécs, Pécs, Hungary.
Transient Receptor Potential (TRP) ion channels like Vanilloid 1 (TRPV1) and Melastatin 3 (TRPM3) are nonselective cation channels expressed in primary sensory neurons and peripheral nerve endings, which are located in cholesterol- and sphingolipid-rich membrane lipid raft regions and have important roles in pain processing. Besides TRP ion channels a wide variety of voltage-gated ion channels were also described in the membrane raft regions of neuronal cells. Here we investigated the effects of lipid raft disruption by methyl-beta-cyclodextrin (MCD) and sphingomyelinase (SMase) on TRPV1, TRPM3 and voltage-gated L-type Ca channel activation in cultured trigeminal neurons and sensory nerve terminals of the trachea.
View Article and Find Full Text PDFBiol Chem
October 2024
Experimental Pain Research, Medical Faculty Mannheim, Heidelberg University, MCTN, Tridomus, Building C, Ludolf-Krehl-Straße 13-17, D-68167 Mannheim, Germany.
Sensory neurons serve to receive and transmit a wide range of information about the conditions of the world around us as well as the external and internal state of our body. Sensitisation of these nerve cells, i.e.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!