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Heliyon May 2024The transient receptor potential ankyrin 1 (TRPA1) channel has become a focus in pain research. However, there are no bibliometric studies that systematically analyze...
BACKGROUND AND AIMS
The transient receptor potential ankyrin 1 (TRPA1) channel has become a focus in pain research. However, there are no bibliometric studies that systematically analyze the existing research in this area. This study aimed to provide a systematic review of the existing literature on TRPA1 using a bibliometric analysis.
METHODS
Published literature in the field of TRPA1 was collected from the Web of Science Core Collection database. Quantitative and qualitative analyses of publications, countries, institutions, authors, journals, and other entries were conducted using Excel, VOSview, and Citespace software to provide insight into global research hotspots and trends in the TRPA1 field.
RESULTS
This study included 1189 scientific products published in 398 journals from 52 countries. The United States of America (n = 367) had the most publications, ahead of Japan (n = 212) and China (n = 199). The University of Florence (n = 55) was the most productive institution and Pierangelo Geppetti (n = 46) was the most productive author. (n = 40) published the most articles on TRPA1. Pain, cold, inflammation, covalent modification, hyperalgesia, and oxidative stress were the most common keywords used in the studies.
CONCLUSION
This study provides the first bibliometric analysis of TRPA1 publications. The physiological functions of TRPA1, TRPA1, and neuropathic pain, TRPA1 as a therapeutic target, and agonists of TRPA1 are trending in TRPA1 research. Neuropathic pain, apoptosis, and sensitization could be focus areas of future research. This study provides important insight in the field of TRPA1 research.
PubMed: 38770319
DOI: 10.1016/j.heliyon.2024.e31001 -
Journal of Traditional Chinese Medicine... Jun 2024To evaluate the analgesic effects of total flavonoids of Longxuejie () (TFDB) and explore the possible analgesic mechanism associated with transient receptor potential...
OBJECTIVE
To evaluate the analgesic effects of total flavonoids of Longxuejie () (TFDB) and explore the possible analgesic mechanism associated with transient receptor potential vanilloid 1 (TRPV1).
METHODS
Whole-cell patch clamp technique was used to observe the effects of TFDB on capsaicin-induced TRPV1 currents. Rat experiments were used to observe the analgesic effects of TFDB. Western blot and immunofluorescence experiments were used to test the change of TRPV1 expression in DRG neurons induced by TFDB.
RESULTS
Results showed that TFDB inhibited capsaicin-induced TRPV1 receptor currents in acutely isolated dorsal root ganglion (DRG) neurons of rats and the half inhibitory concentration was (16.7 ± 1.6) mg/L. TFDB (2-20 mg/kg) showed analgesic activity in the phase Ⅱ of formalin test and (0.02-2 mg per paw) reduced capsaicin-induced licking times of rats. TFDB (20 mg/kg) was fully efficacious on complete Freund's adjuvant (CFA)-induced inflammatory thermal hyperalgesia and capsaicin could weaken the analgesic effects. The level of TRPV1 expressions of DRG neurons was also decreased in TFDB-treated CFA-inflammatory pain rats.
CONCLUSION
All these results indicated that the analgesic effect of TFDB may contribute to their modulations on both function and expression of TRPV1 channels in DRG neurons.
Topics: Animals; TRPV Cation Channels; Rats; Flavonoids; Analgesics; Male; Rats, Sprague-Dawley; Ganglia, Spinal; Humans; Drugs, Chinese Herbal; Neurons; Pain
PubMed: 38767627
DOI: 10.19852/j.cnki.jtcm.20240423.004 -
BioRxiv : the Preprint Server For... May 2024Adolescent drug exposure has been associated with more severe mental health outcomes related to substance abuse and anxiety disorders. The aim of the present study was...
Adolescent drug exposure has been associated with more severe mental health outcomes related to substance abuse and anxiety disorders. The aim of the present study was to contrast the long-term effects of repeated heroin vapor inhalation during adolescence with similar heroin exposure in adulthood. Groups of female Wistar rats underwent twice daily 30-minute sessions of heroin or propylene glycol (control) vapor inhalation from postnatal days (PND) 36-45 or PND 85-94, respectively. Nociception was assessed after vapor inhalation sessions and forty days later, for the Adolescent-Exposed and Adult-Exposed groups. Anxiety-like behavior was assessed with an elevated plus-maze (EPM) and spatial learning was assessed with a Barnes maze. Acute effects of naloxone (0.3 mg/kg, i.p.) and heroin (0.5 and 1.0 mg/kg, s.c.) on thermal nociception were determined on PND 140/189 and PND 149/198, respectively. Repeated heroin vapor inhalation produced anti-nociceptive tolerance across sessions in both adolescent and adult rats, with the adolescents exhibiting more complete tolerance. Heroin vapor inhalation produced anxiolytic effects, regardless of age of exposure. There were no effects of heroin on spatial learning. Naloxone produced acute hyperalgesia in all but the Adolescent-Exposed heroin group, and heroin anti-nociception was blunted in both heroin-exposed groups at the highest heroin dose. Repeated heroin vapor inhalation can produce lasting effects on nociception and anxiety-like behavior that persist for months after the exposure. Importantly, these findings suggest that adolescent exposure to heroin vapor produces specific effects on nociception that are not observed when exposure occurs in adulthood.
PubMed: 38765990
DOI: 10.1101/2024.05.06.592492 -
Biological Psychology Jul 2024Negative expectations can increase pain sensitivity, leading to nocebo hyperalgesia. However, the physiological and psychological factors that predispose individuals to... (Randomized Controlled Trial)
Randomized Controlled Trial
Negative expectations can increase pain sensitivity, leading to nocebo hyperalgesia. However, the physiological and psychological factors that predispose individuals to this phenomenon are still not well understood. The present study examined whether stress induced by a social stressor affects nocebo hyperalgesia, and whether this effect is mediated by self-reported and physiological stress responses. We recruited 52 healthy participants (15 men) who were randomly assigned to either the Trier Social Stress Test (TSST) or a control condition (a friendly version of the TSST). Nocebo hyperalgesia was induced using negative suggestions combined with a validated pain conditioning paradigm. We assessed self-reported (anxiety and stress) and physiological (cortisol, alpha-amylase, heart rate, and skin conductance) responses to stress. Both groups exhibited significant nocebo hyperalgesia. The stress group showed higher levels of anxiety, self-reported stress, and cortisol levels compared to the control group while no significant differences were found in other physiological markers. The stress and control groups did not differ in the magnitude of nocebo hyperalgesia, but anxiety levels partially mediated the effects of the stress test on nocebo hyperalgesia. Our findings suggest that an external social stressor does not directly affect nocebo hyperalgesia, but that increased anxiety due to the stressor enhances its magnitude. Thus, it may be worthwhile to investigate whether reducing stress-related anxiety in clinical settings would help alleviate nocebo effects.
Topics: Humans; Male; Female; Hyperalgesia; Hydrocortisone; Self Report; Nocebo Effect; Young Adult; Stress, Psychological; Galvanic Skin Response; Adult; Heart Rate; Anxiety; Stress, Physiological; Pain Measurement; Saliva; alpha-Amylases; Pain Threshold
PubMed: 38762001
DOI: 10.1016/j.biopsycho.2024.108818 -
Experimental & Molecular Medicine May 2024Neuropathic pain is a debilitating condition caused by the hyperexcitability of spinal dorsal horn neurons and is often characterized by allodynia. Although...
Neuropathic pain is a debilitating condition caused by the hyperexcitability of spinal dorsal horn neurons and is often characterized by allodynia. Although neuron-independent mechanisms of hyperexcitability have been investigated, the contribution of astrocyte-neuron interactions remains unclear. Here, we show evidence of reactive astrocytes and their excessive GABA release in the spinal dorsal horn, which paradoxically leads to the tonic excitation of neighboring neurons in a neuropathic pain model. Using multiple electrophysiological methods, we demonstrated that neuronal hyperexcitability is attributed to both increased astrocytic GABA synthesis via monoamine oxidase B (MAOB) and the depolarized reversal potential of GABA-mediated currents (E) via the downregulation of the neuronal K/Cl cotransporter KCC2. Furthermore, longitudinal 2-deoxy-2-[F]-fluoro-D-glucose microPET imaging demonstrated increased regional glucose metabolism in the ipsilateral dorsal horn, reflecting neuronal hyperexcitability. Importantly, inhibiting MAOB restored the entire astrocytic GABA-mediated cascade and abrogated the increased glucose metabolism and mechanical allodynia. Overall, astrocytic GABA-mediated tonic excitation is critical for neuronal hyperexcitability, leading to mechanical allodynia and neuropathic pain.
Topics: Astrocytes; Animals; Neuralgia; Glucose; gamma-Aminobutyric Acid; Male; Mice; Neurons; Hyperalgesia; Posterior Horn Cells; Monoamine Oxidase; Disease Models, Animal; Rats; K Cl- Cotransporters
PubMed: 38760512
DOI: 10.1038/s12276-024-01232-z -
Molecular Pain May 2024Transient Receptor Potential Vanilloid 1 (TRPV1) is a nonselective cation channel expressed by pain-sensing neurons and has been an attractive target for the development...
Transient Receptor Potential Vanilloid 1 (TRPV1) is a nonselective cation channel expressed by pain-sensing neurons and has been an attractive target for the development of drugs to treat pain. Recently, Src homology region 2 domain-containing phosphatase-1 (SHP-1, encoded by ) was shown to dephosphorylate TRPV1 in dorsal root ganglia (DRG) neurons, which was linked with alleviating different pain phenotypes. These previous studies were performed in male rodents only and did not directly investigate the role of SHP-1 in TRPV-1 mediated sensitization. Therefore, our goal was to determine the impact of overexpression on TRPV1-mediated neuronal responses and capsaicin-induced pain behavior in mice of both sexes. Twelve-week-old male and female mice overexpressing (Shp1-Tg) and their wild type (WT) littermates were used. overexpression was confirmed in the DRG of Shp1-Tg mice by RNA hybridization and RT-qPCR. and were found to be co-expressed in DRG sensory neurons in both genotypes. Functionally, this overexpression resulted in lower magnitude intracellular calcium responses to 200 nM capsaicin stimulation in DRG cultures from Shp1-Tg mice compared to WTs. , we tested the effects of overexpression on capsaicin-induced pain through a model of capsaicin footpad injection. While capsaicin injection evoked nocifensive behavior (paw licking) and paw swelling in both genotypes and sexes, only WT mice developed mechanical allodynia after capsaicin injection. We observed similar level of TRPV1 protein expression in the DRG of both genotypes, however, a higher amount of tyrosine phosphorylated TRPV1 was detected in WT DRG. These experiments suggest that, while SHP-1 does not mediate the acute swelling and nocifensive behavior induced by capsaicin, it does mediate a protective effect against capsaicin-induced mechanical allodynia in both sexes. The protective effect of SHP-1 might be mediated by TRPV1 dephosphorylation in capsaicin-sensitive sensory neurons of the DRG.
PubMed: 38752471
DOI: 10.1177/17448069241258106 -
Plastic and Reconstructive Surgery.... May 2024Wartenberg syndrome, also known as Cheiralgia paresthetica, is an uncommon neuropathy affecting the superficial branch of the radial nerve. Typically caused by external...
Wartenberg syndrome, also known as Cheiralgia paresthetica, is an uncommon neuropathy affecting the superficial branch of the radial nerve. Typically caused by external compression, it manifests as paresthesia or pain in the radial side of the hand. We present a case of Wartenberg syndrome resulting from combat shrapnel injury, illustrating an uncommon etiology. A 21-year-old soldier was presented with allodynia and paresthesia after a shrapnel explosion, with positive clinical findings and radiographic evidence supporting the diagnosis. Nonoperative management led to significant improvement, highlighting the importance of conservative treatment in such cases. This report underscores the significance of considering unconventional causes in nerve entrapment syndromes post combat trauma, emphasizing adherence to established therapeutic guidelines.
PubMed: 38752214
DOI: 10.1097/GOX.0000000000005818 -
Cureus Apr 2024We present a case of cytomegalovirus (CMV) polyradiculopathy which occurred concomitantly with CMV encephalitis and CMV retinitis in a patient with HIV/AIDS. Our...
We present a case of cytomegalovirus (CMV) polyradiculopathy which occurred concomitantly with CMV encephalitis and CMV retinitis in a patient with HIV/AIDS. Our patient is a 43-year-old male who was admitted with progressive changes in mentation. Cerebrospinal fluid (CSF) analysis showed elevated white blood cell (WBC), low glucose, and elevated protein. The polymerase chain reaction (PCR) panel of CSF was positive for CMV, and other microbiology results were negative. Extensive bilateral CMV retinitis was also noted. The patient was started on ganciclovir and foscarnet, and two weeks after, highly active antiretroviral therapy (HAART) was initiated using Truvada and dolutegravir. The hospital course was complicated by urinary retention and bilateral lower extremity weakness with hypotonia, severe hyperalgesia, and allodynia. An electromyography (EMG) study demonstrated bilateral lumbosacral root dysfunction at L2-S1 with active neurologic changes indicating significant axon loss. Neurology was consulted, and the patient was diagnosed with CMV-induced polyradiculopathy. After three months of treatment, no improvement was noted on lower limbs as he continued with intravenous (IV) ganciclovir. The therapeutic response to induction therapy was discordant as improvement of encephalitis was noted, but not on polyradiculopathy after 180 days of treatment. This highlights the lack of data and treatment guidelines for established CMV polyradiculopathy and not only the necessity for prolonged treatment of CMV polyradiculopathy but also the difficulty in recovery of function once it has developed.
PubMed: 38752099
DOI: 10.7759/cureus.58230 -
Saudi Pharmaceutical Journal : SPJ :... Jun 2024Oxidative stress accumulation becomes a pathophysiological factor in diabetic neuropathy (DN), activating TRPV-1. Resveratrol in cocoa pod husk exhibits antioxidant...
Oxidative stress accumulation becomes a pathophysiological factor in diabetic neuropathy (DN), activating TRPV-1. Resveratrol in cocoa pod husk exhibits antioxidant activity that could be beneficial in DN. This study examined how the ethanol extract of cocoa pod husk (EECPH) affects DN in mice by targeting TRPV-1. Cocoa pod husk was extracted using 96 % ethanol with remaceration. The antioxidant activity was measured using DPPH. Mice were induced using alloxan 210 mg/kg BW i.p. At day 14, mice were randomized into seven groups: normal, diabetic, gabapentin 100 mg/kg BW, metformin 250 mg/kg BW, and EECPH (doses 250, 500, and 750 mg/kg BW). Treatments were administered orally, once daily for 14 days. The latency time and blood glucose levels were measured on days 7, 14, 21, and 28. On day 29, mice were sacrificed, and the blood, pancreas, and spinal cord were removed. Malondialdehyde, cholesterol, and serum glutamic oxaloacetic/pyruvic transaminase (SGOT/PT) were examined. Morphology of the spinal cord and pancreas was determined using hematoxylin and eosin staining. The expression of TRPV-1 was assessed using immunohistochemistry. he EECPH dose of 750 mg/kg BW showed the greatest effect in lowering hyperalgesia and blood glucose as well as cholesterol and SGOT/PT in mice. That dose also improved the histology of the pancreas and spinal cord by altering the expression of TRPV-1. It can be concluded that EECPH may lower the expression of TRPV-1 in the pancreas and spinal cord of mice. This activity was responsible of reducing hyperalgesia in DN mice.
PubMed: 38746850
DOI: 10.1016/j.jsps.2024.102097 -
Molecular Pain 2024Recent studies have demonstrated that activated microglia were involved in the pathogenesis of central sensitization characterized by cutaneous allodynia in migraine....
Recent studies have demonstrated that activated microglia were involved in the pathogenesis of central sensitization characterized by cutaneous allodynia in migraine. Activation of microglia is accompanied by increased expression of its receptors and release of inflammatory mediators. Acupuncture and its developed electroacupuncture (EA) have been recommended as an alternative therapy for migraine and are widely used for relieving migraine-associated pain. However, it remains rare studies that show whether EA exerts anti-migraine effects via inhibiting microglial activation related to a release of microglial receptors and the inflammatory pathway. Therefore, this study aimed to investigate EA' ability to ameliorate central sensitization via modulation of microglial activation, microglial receptor, and inflammatory response using a rat model of migraine induced by repeated epidural chemical stimulation. In the present study, a rat model of migraine was established by epidural repeated inflammatory soup (IS) stimulation and treated with EA at Fengchi (GB20) and Yanglingquan (GB34) and acupuncture at sham-acupoints. Pain hypersensitivity was further determined by measuring the mechanical withdrawal threshold using the von-Frey filament. The changes in c-Fos and ionized calcium binding adaptor molecule 1 (Ibal-1) labeled microglia in the trigeminal nucleus caudalis (TNC) were examined by immunflurescence to assess the central sensitization and whether accompanied with microglia activation. In addition, the expression of Ibal-1, microglial purinoceptor P2X4, and its associated inflammatory signaling pathway mediators, including interleukin (IL)-1β, NOD-like receptor protein 3 (NLRP3), and Caspase-1 in the TNC were investigated by western blot and real-time polymerase chain reaction analysis. Allodynia increased of c-Fos, and activated microglia were observed after repeated IS stimulation. EA alleviated the decrease in mechanical withdrawal thresholds, reduced the activation of c-Fos and microglia labeled with Ibal-1, downregulated the level of microglial purinoceptor P2X4, and limited the inflammatory response (NLRP3/Caspase-1/IL-1β signaling pathway) in the TNC of migraine rat model. Our results indicate that the anti-hyperalgesia effects of EA ameliorate central sensitization in IS-induced migraine by regulating microglial activation related to P2X4R and NLRP3/IL-1β inflammatory pathway.
Topics: Animals; Electroacupuncture; Receptors, Purinergic P2X4; Microglia; Hyperalgesia; Migraine Disorders; Rats, Sprague-Dawley; Disease Models, Animal; Male; Inflammation; Central Nervous System Sensitization; Rats; NLR Family, Pyrin Domain-Containing 3 Protein; Proto-Oncogene Proteins c-fos
PubMed: 38744426
DOI: 10.1177/17448069241258113