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Background: Insufficiently managed incisional (INC) pain severely affects patients' life quality and rehabilitation after a major operation. However, mechanisms underlying INC pain still remain poorly understood. Methods: A mouse model of INC pain was established by skin plus deep muscle incision. Biochemistry assay, in vivo reactive oxygen species (ROS) imaging, Ca2+ imaging combined with retrograde labelling, neuron tracing and nocifensive behavior test, etc. were utilized for mechanism investigation. Results: We found pro-nociceptive cytokine interleukin -33 (IL-33) ranked among top up-regulated cytokines in incised tissues of INC pain model mice. IL-33 was predominantly expressed in keratinocytes around the incisional area. Neutralization of IL-33 or its receptor suppression of tumorigenicity 2 protein (ST2) or genetic deletion of St2 gene (St2 -/-) remarkably ameliorated mechanical allodynia and improved gait impairments of model mice. IL-33 contributes to INC pain by recruiting macrophages, which subsequently release ROS in incised tissues via ST2-dependent mechanism. Transfer of excessive macrophages enhanced oxidative injury and reproduced mechanical allodynia in St2 -/- mice upon tissue incision. Overproduced ROS subsequently activated functionally up-regulated transient receptor potential ankyrin subtype-1 (TRPA1) channel innervating the incisional site to produce mechanical allodynia. Neither deleting St2 nor attenuating ROS affected wound healing of model mice. Conclusions: Our work uncovered a previously unrecognized contribution of IL-33/ST2 signaling in mediating mechanical allodynia and gait impairment of a mouse model of INC pain. Targeting IL-33/ST2 signaling could be a novel therapeutic approach for INC pain management.
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Modelos Animales de Enfermedad , Hiperalgesia , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-33 , Macrófagos , Ratones Noqueados , Especies Reactivas de Oxígeno , Canal Catiónico TRPA1 , Animales , Interleucina-33/metabolismo , Interleucina-33/genética , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/genética , Especies Reactivas de Oxígeno/metabolismo , Ratones , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Macrófagos/metabolismo , Hiperalgesia/metabolismo , Piel/metabolismo , Masculino , Ratones Endogámicos C57BL , Queratinocitos/metabolismo , Dolor/metabolismoRESUMEN
Sensing of noxious heat has been reported to be mediated by TRPV1, TRPA1, TRPM3, and ANO1 in mice, and this is redundant so that the loss of one receptor is at least partially compensated for by others. We have established an infusion-based human heat pain model. Heat-induced pain probed with antagonists for the four receptors did not match the redundancy found in mice. In healthy participants, only TRPV1 contributes to the detection of noxious heat; none of the other three receptors are involved. TRPV1 inhibition reduced the pain at all noxious temperatures, which can also be seen as an increase in the temperature that causes a particular level of pain. However, even if the TRPV1-dependent shift in heat detection is about 1°C, at the end of the temperature ramp to 52°C, most heat-induced pain remains unexplained. This difference between species reopens the quest for the molecular safety net for the detection of noxious heat in humans.
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Calor , Canales Catiónicos TRPV , Sensación Térmica , Humanos , Canales Catiónicos TRPV/antagonistas & inhibidores , Canales Catiónicos TRPV/metabolismo , Masculino , Adulto , Animales , Femenino , Ratones , Estudios Cruzados , Dolor , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Canal Catiónico TRPA1/antagonistas & inhibidores , Adulto JovenRESUMEN
Transient receptor potential (TRP) channels, first identified in Drosophila in 1969, are multifunctional ion channels expressed in various cell types. Structurally, TRP channels consist of six membrane segments and are classified into seven subfamilies. Transient receptor potential ankyrin 1 (TRPA1), the first member of the TRPA family, is a calcium ion affinity non-selective cation channel involved in sensory transduction and responds to odors, tastes, and chemicals. It also regulates temperature and responses to stimuli. Recent studies have linked TRPA1 to several disorders, including chronic pain, inflammatory diseases, allergies, and respiratory problems, owing to its activation by environmental toxins. Mutations in TRPA1 can affect the sensory nerves and microvasculature, potentially causing nerve pain and vascular problems. Understanding the function of TRPA1 is important for the development of treatments for these diseases. Recent developments in nanomedicines that target various ion channels, including TRPA1, have had a significant impact on disease treatment, providing innovative alternatives to traditional disease treatments by overcoming various adverse effects.
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Canal Catiónico TRPA1 , Humanos , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Animales , Nanomedicina/métodos , Hipersensibilidad/tratamiento farmacológico , Hipersensibilidad/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Dolor Crónico/tratamiento farmacológico , Dolor Crónico/metabolismoRESUMEN
Maladaptive changes of metabolic patterns in the lumbar dorsal root ganglion (DRG) are critical for nociceptive hypersensitivity genesis. The accumulation of branched-chain amino acids (BCAAs) in DRG has been implicated in mechanical allodynia and thermal hyperalgesia, but the exact mechanism is not fully understood. This study aimed to explore how BCAA catabolism in DRG modulates pain sensitization. Wildtype male mice were fed a high-fat diet (HFD) for 8 weeks. Adult PP2Cmfl/fl mice of both sexes were intrathecally injected with pAAV9-hSyn-Cre to delete the mitochondrial targeted 2 C-type serine/threonine protein phosphatase (PP2Cm) in DRG neurons. Here, we reported that BCAA catabolism was impaired in the lumbar 4-5 (L4-L5) DRGs of mice fed a high-fat diet (HFD). Conditional deletion of PP2Cm in DRG neurons led to mechanical allodynia, heat and cold hyperalgesia. Mechanistically, the genetic knockout of PP2Cm resulted in the upregulation of C-C chemokine ligand 5/C-C chemokine receptor 5 (CCL5/CCR5) axis and an increase in transient receptor potential ankyrin 1 (TRPA1) expression. Blocking the CCL5/CCR5 signaling or TRPA1 alleviated pain behaviors induced by PP2Cm deletion. Thus, targeting BCAA catabolism in DRG neurons may be a potential management strategy for pain sensitization.
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Aminoácidos de Cadena Ramificada , Dieta Alta en Grasa , Ganglios Espinales , Hiperalgesia , Animales , Ganglios Espinales/metabolismo , Masculino , Hiperalgesia/metabolismo , Aminoácidos de Cadena Ramificada/metabolismo , Ratones , Dieta Alta en Grasa/efectos adversos , Femenino , Ratones Endogámicos C57BL , Neuronas/metabolismo , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Ratones Noqueados , Receptores CCR5/metabolismo , Receptores CCR5/genéticaRESUMEN
Osteoporosis (OP) is a disorder of bone remodeling caused by an imbalance between bone resorption by osteoclasts and bone formation by osteoblasts. Therefore, inhibiting excessive osteoclast activity is one of the promising strategies for treating OP. A major transient receptor potential cation channel, known as transient receptor potential ankyrin 1 (TRPA1), was found to alleviate joint pain and cartilage degeneration in osteoarthritis. However, little research has focused on TRPA1 function in OP. As a result, this study aimed to explore the TRPA1 characteristics and its potential therapeutic function during osteoclastogenesis. The TRPA1 expression gradually increased in the osteoclast differentiation process; however, its suppression with small interfering RNA and an inhibitor (HC030031) significantly controlled the osteoclast count and the expression of osteoclast characteristic genes. Its suppression also inhibited endoplasmic reticulum (ER) stress-related pancreatic ER kinase (PERK) pathways. An ER stress inhibitor (thapsigargin) reversed the down-regulated levels of ER stress and osteoclast differentiation by suppressing TRPA1. Transcriptome sequencing results demonstrated that TRPA1 negatively regulated reactive oxygen species (ROS) and significantly increased the expression of an antioxidant gene, SRXN1. The osteoclast differentiation and the levels of ER stress were enhanced with SRXN1 inhibition. Finally, TRPA1 knockdown targeting macrophages by adeno-associated virus-9 could relieve osteoclast differentiation and osteopenia in ovariectomized mice. In summary, silencing TRPA1 restrained osteoclast differentiation through ROS-mediated down-regulation of ER stress via inhibiting PERK pathways. The study also indicated that TRPA1 might become a prospective treatment target for OP.
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Diferenciación Celular , Estrés del Retículo Endoplásmico , Osteoclastos , Osteogénesis , Osteoporosis , Canal Catiónico TRPA1 , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Animales , Osteoporosis/metabolismo , Osteoporosis/patología , Osteoporosis/genética , Ratones , Osteoclastos/metabolismo , Osteogénesis/efectos de los fármacos , Femenino , Ratones Endogámicos C57BL , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismoRESUMEN
INTRODUCTION: The olfactory and trigeminal system are closely interlinked. Existing literature has primarily focused on characterizing trigeminal stimulation through mechanical and chemical stimulation, neglecting thermal stimulation thus far. The present study aimed to characterize the intranasal sensitivity to heat and the expression of trigeminal receptors (transient receptor potential channels, TRP). METHODS: A total of 20 healthy participants (aged 21-27 years, 11 women) were screened for olfactory function and trigeminal sensitivity using several tests. Under endoscopic control, a thermal stimulator was placed in 7 intranasal locations: anterior septum, lateral vestibulum, interior nose tip, lower turbinate, middle septum, middle turbinate, and olfactory cleft to determine the thermal threshold. Nasal swabs were obtained in 3 different locations (anterior septum, middle turbinate, olfactory cleft) to analyze the expression of trigeminal receptors TRP: TRPV1, TRPV3, TRPA1, TRPM8. RESULTS: The thermal threshold differed between locations (p = 0.018), with a trend for a higher threshold at the anterior septum (p = 0.092). There were no differences in quantitative receptor expression (p = 0.46) at the different sites. The highest overall receptor RNA expression was detected for TRPV1 over all sites (p<0.001). The expression of TRPV3 was highest at the anterior septum compared to the middle turbinate or the olfactory cleft. The thermal sensitivity correlated with olfactory sensitivity and results from tests were related to trigeminal function like intensity ratings of ammonium, a questionnaire regarding trigeminal function, nasal patency, and CO2 thresholds. However, no correlation was found between receptor expression and psychophysical measures of trigeminal function. DISCUSSION: This study provided the first insights about intranasal thermal sensitivity and suggested the presence of topographical differences in thermal thresholds. There was no correlation between thermal sensitivity and trigeminal mRNA receptor expression. However, thermal sensitivity was found to be associated with psychophysical measures of trigeminal and olfactory function.
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Mucosa Nasal , Canales Catiónicos TRPV , Humanos , Femenino , Adulto , Masculino , Mucosa Nasal/metabolismo , Adulto Joven , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/genética , Calor , Nervio Trigémino/fisiología , Nervio Trigémino/metabolismo , Umbral Sensorial/fisiología , Canales de Potencial de Receptor Transitorio/metabolismo , Canales de Potencial de Receptor Transitorio/genética , Canales Catiónicos TRPM/metabolismo , Canales Catiónicos TRPM/genética , Sensación Térmica/fisiología , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genéticaRESUMEN
The development of noninvasive approaches to precisely control neural activity in mammals is highly desirable. Here, we used the ion channel transient receptor potential ankyrin-repeat 1 (TRPA1) as a proof of principle, demonstrating remote near-infrared (NIR) activation of endogenous neuronal channels in mice through an engineered nanoagonist. This achievement enables specific neurostimulation in nongenetically modified mice. Initially, target-based screening identified flavins as photopharmacological agonists, allowing for the photoactivation of TRPA1 in sensory neurons upon ultraviolet A/blue light illumination. Subsequently, upconversion nanoparticles (UCNPs) were customized with an emission spectrum aligned to flavin absorption and conjugated with flavin adenine dinucleotide, creating a nanoagonist capable of NIR activation of TRPA1. Following the intrathecal injection of the nanoagonist, noninvasive NIR stimulation allows precise bidirectional control of nociception in mice through remote activation of spinal TRPA1. This study demonstrates a noninvasive NIR neurostimulation method with the potential for adaptation to various endogenous ion channels and neural processes by combining photochemical toolboxes with customized UCNPs.
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Rayos Infrarrojos , Nanopartículas , Canal Catiónico TRPA1 , Animales , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/agonistas , Ratones , Nanopartículas/química , Células Receptoras Sensoriales/metabolismo , Células Receptoras Sensoriales/fisiología , Células Receptoras Sensoriales/efectos de los fármacos , Canales Iónicos/metabolismo , Nocicepción/efectos de los fármacosRESUMEN
The pathogenesis mechanism of acute gastric mucosal lesions (AGML) is still unclear; further exploration is urgently needed to find a new therapeutic target. This study aimed to investigate whether morphine might regulate the expression and function of transient receptor potential ankyrin 1 (TRPA1) through a cyclic adenosine monophosphate/protein kinase A (cAMP/PKA)-dependent pathway, thereby alleviating gastric mucosal lesions caused by water-immersion restraint stress (WIRS). Rats were administered with intrathecal morphine, TRPA1 antagonist (HC-030031), µ-opioid receptor antagonist, or protein kinase A inhibitor (H-89), respectively, before WIRS. After 6 hours of WIRS, microscopic lesions, hematoxylin and eosin staining, and transmission electron microscopy were applied to assess the damage of the gastric mucosa. Real-time polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay were conducted to detect the levels of TRPA1 and substance P (SP) in the dorsal root ganglia (DRG) and gastric tissues. In addition, immunofluorescence was used to explore the possible co-expression of TRPA1 and µ-opioid receptors in the DRG. The results indicated that WIRS upregulated TRPA1 and SP in gastric mucosa, and HC-030031 or H-89 could alleviate gastric mucosal lesions caused by WIRS (P < .0001). Morphine was found to suppress both WIRS-induced gastric mucosal lesions (P < .0001) and the upregulation of TRPA1 (P = .0086) and SP (P = .0013). Both TRPA1 and SP play important roles in the pathogenesis of WIRS-induced AGML. Exogenous gastroprotective strategies reduce elevated levels of TRPA1 via the cAMP/PKA-dependent pathway. Inhibition of TRPA1 upregulation in the DRG is critical for intrathecal morphine preconditioning-induced gastric protection.
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Ganglios Espinales , Mucosa Gástrica , Isoquinolinas , Morfina , Ratas Sprague-Dawley , Restricción Física , Canal Catiónico TRPA1 , Regulación hacia Arriba , Animales , Morfina/farmacología , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Canal Catiónico TRPA1/metabolismo , Masculino , Ganglios Espinales/metabolismo , Ganglios Espinales/efectos de los fármacos , Restricción Física/efectos adversos , Ratas , Isoquinolinas/farmacología , Acetanilidas/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Purinas/farmacología , Estrés Psicológico/complicaciones , Inmersión , Receptores Opioides mu/metabolismo , AMP Cíclico/metabolismo , SulfonamidasRESUMEN
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.
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Antifúngicos , Calcio , Econazol , Ganglios Espinales , Células Receptoras Sensoriales , Canal Catiónico TRPA1 , Canales Catiónicos TRPV , Canales de Potencial de Receptor Transitorio , Animales , Econazol/farmacología , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Antifúngicos/toxicidad , Antifúngicos/farmacología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Ganglios Espinales/citología , Humanos , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Canales de Potencial de Receptor Transitorio/genética , Células HEK293 , Calcio/metabolismo , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/genética , Ratones , Masculino , Ratones Noqueados , Ratones Endogámicos C57BL , Prurito/inducido químicamente , Dolor/tratamiento farmacológicoRESUMEN
Tuina is a treatment method in traditional Chinese medicine which has analgesic effects and effectively alleviates the symptoms of neuropathic pain (NP). Transient receptor potential vanilloid type 1 (TRPV1) and transient receptor potential ankyrin type 1 (TRPA1) play major roles in transmitting nociceptive sensory signals in the nociceptive primary sensory dorsal root ganglion (DRG) nerve. The nitric oxide (NO)/cyclic guanosine 3',5'-monophosphate(cGMP) pathway exerts both nociceptive and antinociceptive effects in various chronic pain models. TRPV1 and TRPA1 mediate the influx of calcium, which stimulates the generation of NO. Subsequently, NO activates the NO/cGMP/protein kinase G (PKG) signaling pathway, thereby improving hyperalgesia. In the present study, oa rat model of NP with minor chronic constriction injury (CCI) of the right sciatic nerve of NP was established. The results of behavioral testing showed that, after a one-time tuina intervention, the mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were prolonged to varying degrees in the tuina group compared with the model group. Similarly, the expression of TRPV1, TRPA1, NO, soluble guanylate cyclase ß (sGCß), cGMP, and PKG1 was significantly decreased in the DRG of the tuina and tuina + TRPV1/TRPA1 antagonist group was significantly decreased. These findings suggest that the tuina intervention can effectively improve the symptoms of thermal and mechanical allodynia caused by peripheral nerve injuries. Tuina exerts immediate analgesic effects through the TRPV1/TRPA1-NO-cGMP-PKG signaling pathway.
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GMP Cíclico , Modelos Animales de Enfermedad , Ganglios Espinales , Ratas Sprague-Dawley , Transducción de Señal , Canal Catiónico TRPA1 , Canales Catiónicos TRPV , Animales , Ganglios Espinales/metabolismo , Canales Catiónicos TRPV/metabolismo , Masculino , GMP Cíclico/metabolismo , Canal Catiónico TRPA1/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Ratas , Neuralgia/metabolismo , Neuralgia/tratamiento farmacológico , Analgésicos/farmacología , Analgésicos/uso terapéutico , Hiperalgesia/metabolismo , Hiperalgesia/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional ChinaRESUMEN
Although biocides are important materials in modern society and help protect human health and the environment, increasing exposure to combined biocides can cause severe side effects in the human body, such as lung fibrosis. In this study, we developed a receptonics system to screen for biocides in combined household chemical products based on biocides. The system contains transient receptor potential ankyrin 1 (TRPA1) nanovesicles (NVs) to sense biocides based on pain receptors and a side-gated field-effect transistor (SGFET) using a single-layer graphene (SLG) micropattern channel. The binding affinities between the TRPA1 receptor and the various biocides were estimated by performing biosimulation and using a calcium ion (Ca2+) assay, and the sensitivity of the system was compared with that of TRPA1 NV receptonics systems. Based on the results of the TRPA1 NV receptonics system, the antagonistic and potentiation effects of combined biocides and household chemical products depended on the concentration. Finally, the TRPA1 NV receptonics system was applied to screen for biocides in real products, and its performance was successful. Based on these results, the TRPA1 NV receptonics system can be utilized to perform risk evaluations and identify biocides in a simple and rapid manner.
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Desinfectantes , Canal Catiónico TRPA1 , Canal Catiónico TRPA1/metabolismo , Desinfectantes/toxicidad , Desinfectantes/química , Humanos , Grafito/toxicidad , Grafito/química , Células HEK293 , Calcio/metabolismo , Transistores ElectrónicosRESUMEN
Although the introduction of drugs targeting calcitonin gene-related peptide (CGRP) revolutionized migraine treatment, still a substantial proportion of migraine patients do not respond satisfactorily to such a treatment, and new therapeutic targets are needed. Therefore, molecular studies on migraine pathogenesis are justified. Oxidative stress is implicated in migraine pathogenesis, as many migraine triggers are related to the production of reactive oxygen and nitrogen species (RONS). Migraine has been proposed as a superior mechanism of the brain to face oxidative stress resulting from energetic imbalance. However, the precise mechanism behind the link between migraine and oxidative stress is not known. Nociceptive primary afferent nerve fiber endings express ion channel receptors that change harmful stimuli into electric pain signals. Transient receptor potential cation channel subfamily A member 1 (TRPA1) is an ion channel that can be activated by oxidative stress products and stimulate the release of CGRP from nerve endings. It is a transmembrane protein with ankyrin repeats and conserved cysteines in its N-terminus embedded in the cytosol. TRPA1 may be a central element of the signaling pathway from oxidative stress and NO production to CGRP release, which may play a critical role in headache induction. In this narrative review, we present information on the role of oxidative stress in migraine pathogenesis and provide arguments that TRPA1 may be "a missing link" between oxidative stress and migraine and therefore a druggable target in this disease.
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Trastornos Migrañosos , Estrés Oxidativo , Canal Catiónico TRPA1 , Humanos , Trastornos Migrañosos/metabolismo , Trastornos Migrañosos/etiología , Canal Catiónico TRPA1/metabolismo , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Transducción de Señal , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Cadaverine is an endogenous metabolite produced by the gut microbiome with various activity in physiological and pathological conditions. However, whether cadaverine regulates pain or itch remains unclear. In this study, we first found that cadaverine may bind to histamine 4 receptor (H4R) with higher docking energy score using molecular docking simulations, suggesting cadaverine may act as an endogenous ligand for H4R. We subsequently found intradermal injection of cadaverine into the nape or cheek of mice induces a dose-dependent scratching response in mice, which was suppressed by a selective H4R antagonist JNJ-7777120, transient receptor potential vanilloid 1 (TRPV1) antagonist capsazepine and PLC inhibitor U73122, but not H1R antagonist or TRPA1 antagonist or TRPV4 antagonist. Consistently, cadaverine-induced itch was abolished in Trpv1-/- but not Trpa1-/- mice. Pharmacological analysis indicated that mast cells and opioid receptors were also involved in cadaverine-induced itch in mice. scRNA-Seq data analysis showed that H4R and TRPV1 are mainly co-expressed on NP2, NP3 and PEP1 DRG neurons. Calcium imaging analysis showed that cadaverine perfusion enhanced calcium influx in the dissociated dorsal root ganglion (DRG) neurons, which was suppressed by JNJ-7777120 and capsazepine, as well as in the DRG neurons from Trpv1-/- mice. Patch-clamp recordings found that cadaverine perfusion significantly increased the excitability of small diameter DRG neurons, and JNJ-7777120 abolished this effect, indicating involvement of H4R. Together, these results provide evidences that cadaverine is a novel endogenous pruritogens, which activates H4R/TRPV1 signaling pathways in the primary sensory neurons.
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Cadaverina , Ganglios Espinales , Ratones Endogámicos C57BL , Prurito , Canales Catiónicos TRPV , Animales , Prurito/metabolismo , Prurito/inducido químicamente , Canales Catiónicos TRPV/metabolismo , Ganglios Espinales/metabolismo , Ganglios Espinales/efectos de los fármacos , Masculino , Cadaverina/análogos & derivados , Cadaverina/farmacología , Cadaverina/metabolismo , Ratones , Ratones Noqueados , Humanos , Mastocitos/metabolismo , Mastocitos/efectos de los fármacos , Canal Catiónico TRPA1/metabolismo , Células Receptoras Sensoriales/metabolismo , Células Receptoras Sensoriales/efectos de los fármacos , Receptores Acoplados a Proteínas G/metabolismo , Capsaicina/análogos & derivadosRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Artemisia argyi Levl.et Vant. have a long history of being used to treat skin diseases such as pruritus and dermatitis in China, but the therapeutic effect on allergic contact dermatitis (ACD) is still unclear. AIM OF THE STUDY: To investigate the effect and molecular mechanisms of the volatile oil of A. argyi leaves (abbreviated as 'AO') in the treatment of ACD. MATERIALS AND METHODS: The main components in AO were analyzed using GC-MS. The effect of AO on channel currents in hTRPA1-transfected HEK293T cells was studied by whole-cell patch clamp. Subsequently, chloroquine-evoked acute itch and squaraine dibutyl ester (SADBE)-induced ACD chronic itch model was established to evaluate the antipruritic effect through counting scratching behavior, and the anti-inflammatory effects on ACD mice were measured using histological analysis. Meanwhile, the changes of CGRP, the infiltration of nerve fibers and the recruitment of dendritic cells, the expression of Il-23 and Il-17 mRNA in skin lesions, the phosphorylation of ERK and p38 in dorsal root ganglion (DRG), were evaluated by molecular biological methods. Then the inhibitory effect of AO on AITC- or SADBE-activated TRPA1 channels in primary DRG neurons of C57BL/6, Trpa1-/- or Trpv1-/- mice was elucidated by Ca2+ imaging and immunofluorescence. RESULTS: AO treatment inhibited the activation of TRPA1 in HEK293T cells and alleviated acute itch caused by chloroquine, but this effect was lacking in Trpa1-/- mice. Furthermore, administration of AO attenuated scratching behavior in SADBE-induced ACD mice. AO also inhibited the increase of nerve fibers and recruitment of dendritic cells, and down-regulated the expression of CGRP and the levels of Il-23 and Il-17 mRNA. Meanwhile, AO reduced the expression of p-p38 and p-ERK in the lesioned skin and DRG of SADBE-induced ACD mice. Additionally, AO blocked the activation of TRPA1 channels and decreased the levels of CGRP, p-p38, and p-ERK in DRG neurons. CONCLUSION: AO could inhibit TRPA1 channels in sensory neurons, thereby reducing the release of CGRP and exerting anti-pruritic and anti-inflammatory effect. These findings also provide a new strategy for exploring the role of A. argyi in treating ACD.
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Artemisia , Péptido Relacionado con Gen de Calcitonina , Dermatitis Alérgica por Contacto , Ratones Endogámicos C57BL , Aceites Volátiles , Transducción de Señal , Canal Catiónico TRPA1 , Animales , Canal Catiónico TRPA1/metabolismo , Humanos , Péptido Relacionado con Gen de Calcitonina/metabolismo , Péptido Relacionado con Gen de Calcitonina/genética , Artemisia/química , Células HEK293 , Transducción de Señal/efectos de los fármacos , Ratones , Masculino , Dermatitis Alérgica por Contacto/tratamiento farmacológico , Dermatitis Alérgica por Contacto/metabolismo , Aceites Volátiles/farmacología , Prurito/tratamiento farmacológico , Prurito/inducido químicamente , Ratones Noqueados , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Hojas de la Planta/química , Modelos Animales de Enfermedad , Antipruriginosos/farmacología , Antipruriginosos/uso terapéuticoRESUMEN
Low temperatures significantly influence feeding behavior in ectothermic vertebrates, but the underlying mechanisms remain elusive. This study investigated the role of transient receptor potential ankyrin 1 (TRPA1) channels in mediating the appetite-suppressing effects of low temperature in Nile tilapia. TRPA1 was found to be highly expressed in the hypothalamus and co-localized with neuropeptide Y (NPY) neurons. Exposure to low temperatures reduced feeding frequency and increased TRPA1 expression. In vitro experiments demonstrated that low temperature and TRPA1 agonists induced calcium influx, which was blocked by a TRPA1 inhibitor. TRPA1 expression exhibited post-prandial increases and was downregulated by fasting. TRPA1 activation dose-dependently inhibited food intake, while its inhibition restored feeding suppressed by low temperature. TRPA1 activation downregulated orexigenic factors and upregulated anorexigenic factors through Ca2+/calmodulin-dependent pathways. These findings suggest that TRPA1 plays a crucial role in sensing low temperatures and regulating feeding behavior in tilapia.
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Cíclidos , Frío , Ingestión de Alimentos , Canal Catiónico TRPA1 , Animales , Cíclidos/metabolismo , Cíclidos/fisiología , Ingestión de Alimentos/efectos de los fármacos , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Calcio/metabolismo , Proteínas de Peces/metabolismo , Proteínas de Peces/genética , Conducta Alimentaria/efectos de los fármacos , Hipotálamo/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacosRESUMEN
Allyl isothiocyanate (AITC) is the pungent ingredient of brassica species, used as a food additive and flavoring agent, including condiments such as wasabi, horseradish, and mustard. Currently, there is much evidence that AITC modulates glucose and lipids metabolism. Interestingly, AITC has been shown to improve glycaemia, and insulin action along with the induction of a deepened decline in blood insulin levels in T2DM rats. Therefore, in the present study, we characterized the role of AITC at a wide concentration range (5, 10, 25, 50, 100 µM) in controlling viability, proliferation, apoptosis, mitochondrial condition, mRNA expression of encoding pancreatic and duodenal homeobox 1 (Pdx1), and Ins1, Ins2 genes, and insulin content in INS-1E cells. The INS-1E cell line is a suitable, and well-characterized model to study beta cell functions. We demonstrate that AITC reduced the viability (p≤0.001) (also in the presence of transient receptor potential cation subfamily A member 1 (TRPA1) selective antagonist; HC-030031; p≤0.05), and proliferation of INS-1E cells (p≤0.001). AITC evoked a significant reduction of mitochondrial membrane potential (p≤0.01) and decreased the intracellular level of adenosine triphosphate (ATP) (p≤0.001) without influence on reactive oxygen species (ROS) level. Additionally, AITC inhibited the insulin mRNA expression (p≤0.001) in INS-1E cells along with insulin content (p≤0.05). Mitochondrial dysfunction is proposed to be a significant disruption mechanism of AITC in INS-1E cells, and it was independent of ROS, and the influx of external calcium.
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Proliferación Celular , Supervivencia Celular , Células Secretoras de Insulina , Insulina , Isotiocianatos , Potencial de la Membrana Mitocondrial , Animales , Isotiocianatos/farmacología , Ratas , Insulina/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Canal Catiónico TRPA1 , TransactivadoresRESUMEN
Ion channels, which are key to physiological regulation and drug discovery, control ion flux across membranes, and their dysregulation leads to various diseases. Ca2+ monitoring is crucial for cellular signaling when performing Ca-based assays in ion channel research; these assays are widely utilized in both academic and pharmaceutical contexts for drug screening and pharmacological profiling. However, existing detection methods are limited by slow detection speeds, low throughput, complex processes, and low analyte viability. In this study, we developed a label-free optical biosensing method using a conical Au/polydimethylsiloxane platform tailored to detect Ca2+ influx in A549-originated nanovesicles facilitated by the transient receptor potential ankyrin 1 (TRPA1) channel. Nanovesicles expressing cellular signaling components mimic TRPA1 signal transduction in cell membranes and improve analyte viability. The conical Au/polydimethylsiloxane sensor converted Ca2+ influx events induced by specific agonist exposure into noticeable changes in relative transmittance under visible light. The optical transmittance change accompanying Ca2+ influx resulted in an enhanced sensing response, high accuracy and reliability, and rapid detection (â¼5 s) without immobilization or ligand treatments. In the underlying sensing mechanism, morphological variations in nanovesicles, which depend on Ca2+ influx, induce a considerable light scattering change at an interface between the nanovesicle and Au, revealed by optical simulation. This study provides a foundation for developing biosensors based on light-matter interactions. These sensors are simple and cost-effective with superior performance and diverse functionality.
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Técnicas Biosensibles , Calcio , Dimetilpolisiloxanos , Oro , Oro/química , Dimetilpolisiloxanos/química , Humanos , Técnicas Biosensibles/instrumentación , Calcio/metabolismo , Células A549 , Canal Catiónico TRPA1/metabolismoRESUMEN
BACKGROUND/AIMS: Tactile perception relies on mechanoreceptors and nerve fibers, including c-fibers, Aß-fibers and Aδ-fibers. Schwann cells (SCs) play a crucial role in supporting nerve fibers, with non-myelinating SCs enwrapping c-fibers and myelinating SCs ensheathing Aß and Aδ fibers. Recent research has unveiled new functions for cutaneous sensory SCs, highlighting the involvement of nociceptive SCs in pain perception and Meissner corpuscle SCs in tactile sensation. Furthermore, Piezo2, previously associated with Merkel cell tactile sensitivity, has been identified in SCs. The goal of this study was to investigate the channels implicated in SC mechanosensitivity and the release process of neurotrophic factor secretion. METHODS: Immortalized IFRS1 SCs and human primary SCs generated two distinct subtypes of SCs: undifferentiated and differentiated SCs. Quantitative PCR was employed to evaluate the expression of differentiation markers and mechanosensitive channels, including TRP channels (TRPV4, TRPM7 and TRPA1) and Piezo channels (Piezo1 and Piezo2). To validate the functionality of specific mechanosensitive channels, Ca2+ imaging and electronic cell sizing experiments were conducted under hypotonic conditions, and inhibitors and siRNAs were used. Protein expression was assessed by Western blotting and immunostaining. Additionally, secretome analysis was performed to evaluate the release of neurotrophic factors in response to hypotonic stimulation, with BDNF, a representative trophic factor, quantified using ELISA. RESULTS: Induction of differentiation increased Piezo2 mRNA expression levels both in IFRS1 and in human primary SCs. Both cell types were responsive to hypotonic solutions, with differentiated SCs displaying a more pronounced response. Gd3+ and FM1-43 effectively inhibited hypotonicity-induced Ca2+ transients in differentiated SCs, implicating Piezo2 channels. Conversely, inhibitors of Piezo1 and TRPM7 (Dooku1 and NS8593, respectively) had no discernible impact. Moreover, Piezo2 in differentiated SCs appeared to participate in regulatory volume decreases (RVD) after cell swelling induced by hypotonic stimulation. A Piezo2 deficiency correlated with reduced RVD and prolonged cell swelling, leading to heightened release of the neurotrophic factor BDNF by upregulating the function of endogenously expressed Ca2+-permeable TRPV4. CONCLUSION: Our study unveils the mechanosensitivity of SCs and implicates Piezo2 channels in the release of neurotrophic factors from SCs. These results suggest that Piezo2 may contribute to RVD, thereby maintaining cellular homeostasis, and may also serve as a negative regulator of neurotrophic factor release. These findings underscore the need for further investigation into the role of Piezo2 in SC function and neurotrophic regulation.
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Factor Neurotrófico Derivado del Encéfalo , Tamaño de la Célula , Canales Iónicos , Células de Schwann , Células de Schwann/metabolismo , Células de Schwann/citología , Humanos , Canales Iónicos/metabolismo , Tamaño de la Célula/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/genética , ARN Interferente Pequeño/metabolismo , Diferenciación Celular , Células Cultivadas , Interferencia de ARN , Calcio/metabolismo , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Mecanotransducción CelularRESUMEN
Caffeine (1,3,7-trimethylxanthine) is a naturally occurring methylxanthine that acts as a potent central nervous system stimulant found in more than 60 different plants and fruits. Although caffeinated beverages are widely and casually consumed, the application of caffeine beyond dietary levels as pharmacologic therapy has been recognized since the beginning of its recorded use. The analgesic and vasoactive properties of caffeine are well known, but the extent of their molecular basis remains an area of active research. There is existing evidence in the literature as to caffeine's effect on TRP channels, the role of caffeine in pain management and analgesia, as well as the role of TRP in pain and analgesia; however, there has yet to be a review focused on the interaction between caffeine and TRP channels. Although the influence of caffeine on TRP has been demonstrated in the lab and in animal models, there is a scarcity of data collected on a large scale as to the clinical utility of caffeine as a regulator of TRP. This review aims to prompt further molecular research to elucidate the specific ligand-host interaction between caffeine and TRP by validating caffeine as a regulator of transient receptor potential (TRP) channels-focusing on the transient receptor potential vanilloid 1 (TRPV1) receptor and transient receptor potential ankyrin 1 (TRPA1) receptor subtypes-and its application in areas of pain.
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Cafeína , Dolor , Canal Catiónico TRPA1 , Canales Catiónicos TRPV , Cafeína/farmacología , Humanos , Canales Catiónicos TRPV/metabolismo , Animales , Canal Catiónico TRPA1/metabolismo , Dolor/tratamiento farmacológico , Dolor/metabolismo , Analgesia/métodos , Analgésicos/farmacología , Analgésicos/uso terapéuticoRESUMEN
Polysulfides are endogenously produced in mammals and generally associated with protective functions. Our aim was to investigate the effect of dimethyl trisulfide (DMTS) in a mouse model of acute stress. DMTS activates transient receptor potential ankyrin 1 (TRPA1) channels and leads to neuropeptide release, potentially that of substance P (SP). We hypothesize that DMTS might inhibit the degrading enzymes of endocannabinoids, so this system was also investigated as another possible pathway for mediating the effects of DMTS. Trpa1 gene wild-type (WT) and knockout (KO) mice were used to confirm the role of the TRPA1 ion channel in mediating the effects of DMTS. C57BL/6J, NK1 gene KO, and Tac1 gene KO mice were used to evaluate the effect of DMTS on the release and expression of SP. Some C57BL/6J animals were treated with AM251, an inhibitor of the cannabinoid CB1 receptor, to elucidate the role of the endocannabinoid system in these processes. Open field test (OFT) and forced swim test (FST) were performed in each mouse strain. A tail suspension test (TST) was performed in Trpa1 WT and KO animals. C-FOS immunohistochemistry was carried out on Trpa1 WT and KO animals. The DMTS treatment increased the number of highly active periods and decreased immobility time in the FST in WT animals, but had no effect on the Trpa1 KO mice. The DMTS administration induced neuronal activation in the Trpa1 WT mice in the stress-related brain areas, such as the locus coeruleus, dorsal raphe nucleus, lateral septum, paraventricular nucleus of the thalamus, and paraventricular nucleus of the hypothalamus. DMTS may have a potential role in the regulation of stress-related processes, and the TRPA1 ion channel may also be involved in mediating the effects of DMTS. DMTS can be an ideal candidate for further study as a potential remedy for stress-related disorders.