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1.
Neurosci Lett ; 792: 136961, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370955

RESUMO

BACKGROUND: Based on the previous findings on the relieving role of gelsemine in neuropathic pain, this research aims to further investigate the relevant regulatory mechanism. METHODS: Targets of gelsemine were predicted using SwissTargetPrediction. The peripheral neuropathic pain rat model was established by ligating spinal nerves, and then gelsemine (10 µg for one day) or dipeptidyl peptidase 4 (DPP4) oligonucleotides (5 µg/day, for 7 days) was injected into intrathecal bolus of rats. The mechanical threshold (0, 1, 2, 4 h after the last injection) was examined to evaluate the mechanical allodynia of rats. After the mechanical threshold measurement, the rats were anesthetized with isoflurane and then sacrificed by cervical dislocation. IBA1- and DPP4-positive cells in the spinal dorsal horn of rats were determined using immunohistochemistry and immunofluorescence assays. The expressions of DPP4, IL-1ß and TNF-α in the spinal dorsal horn of rats were measured by Western blot and quantitative real-time PCR. RESULTS: DPP4 was one of the targets of gelsemine. Gelsemine could elevate the down-regulated mechanical threshold, and lessen the up-regulated IBA1- and DPP4-positive cells and expressions of DPP4, IL-1ß and TNF-α in the spinal dorsal horn of rats with neuropathic pain. DPP4 overexpression reversed the role of gelsemine in neuropathic pain. CONCLUSION: Gelsemine relieves neuropathic pain by down-regulating DPP4 level in rats, providing a novel drug candidate and biomarker for neuropathic pain treatment.


Assuntos
Dipeptidil Peptidase 4 , Neuralgia , Ratos , Animais , Dipeptidil Peptidase 4/metabolismo , Dipeptidil Peptidase 4/uso terapêutico , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo , Modelos Animais de Doenças , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Medula Espinal/metabolismo
2.
J Comp Neurol ; 531(1): 5-24, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36214727

RESUMO

In the spinal cord, sensory-motor circuits controlling motor activity are situated in the dorso-ventral interface. The neurons identified by the expression of the transcription factor Doublesex and mab-3 related transcription factor 3 (Dmrt3) have previously been associated with the coordination of locomotion in horses (Equus caballus, Linnaeus, 1758), mice (Mus musculus, Linnaeus, 1758), and zebrafish (Danio rerio, F. Hamilton, 1822). Based on earlier studies, we hypothesized that, in mice, these neurons may be positioned to receive sensory and central inputs to relay processed commands to motor neurons. Thus, we investigated the presynaptic inputs to spinal Dmrt3 neurons using monosynaptic retrograde replication-deficient rabies tracing. The analysis showed that lumbar Dmrt3 neurons receive inputs from intrasegmental neurons, and intersegmental neurons from the cervical, thoracic, and sacral segments. Some of these neurons belong to the excitatory V2a interneurons and to plausible Renshaw cells, defined by the expression of Chx10 and calbindin, respectively. We also found that proprioceptive primary sensory neurons of type Ia2, Ia3, and Ib, defined by the expression of calbindin, calretinin, and Brn3c, respectively, provide presynaptic inputs to spinal Dmrt3 neurons. In addition, we demonstrated that Dmrt3 neurons receive inputs from brain areas involved in motor regulation, including the red nucleus, primary sensory-motor cortex, and pontine nuclei. In conclusion, adult spinal Dmrt3 neurons receive inputs from motor-related brain areas as well as proprioceptive primary sensory neurons and have been shown to connect directly to motor neurons. Dmrt3 neurons are thus positioned to provide sensory-motor control and their connectivity is suggestive of the classical reflex pathways present in the spinal cord.


Assuntos
Fatores de Transcrição , Peixe-Zebra , Camundongos , Animais , Cavalos , Fatores de Transcrição/metabolismo , Peixe-Zebra/metabolismo , Neurônios Motores/fisiologia , Medula Espinal/metabolismo , Interneurônios/metabolismo , Calbindinas/metabolismo , Tronco Encefálico/metabolismo
3.
PLoS Biol ; 20(11): e3001853, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36395107

RESUMO

The accurate construction of neural circuits requires the precise control of axon growth and guidance, which is regulated by multiple growth and guidance cues during early nervous system development. It is generally thought that the growth and guidance cues that control the major steps of axon development have been defined. Here, we describe cerebellin-1 (Cbln1) as a novel cue that controls diverse aspects of axon growth and guidance throughout the central nervous system (CNS) by experiments using mouse and chick embryos. Cbln1 has previously been shown to function in late neural development to influence synapse organization. Here, we find that Cbln1 has an essential role in early neural development. Cbln1 is expressed on the axons and growth cones of developing commissural neurons and functions in an autocrine manner to promote axon growth. Cbln1 is also expressed in intermediate target tissues and functions as an attractive guidance cue. We find that these functions of Cbln1 are mediated by neurexin-2 (Nrxn2), which functions as the Cbln1 receptor for axon growth and guidance. In addition to the developing spinal cord, we further show that Cbln1 functions in diverse parts of the CNS with major roles in cerebellar parallel fiber growth and retinal ganglion cell axon guidance. Despite the prevailing role of Cbln1 as a synaptic organizer, our study discovers a new and unexpected function for Cbln1 as a general axon growth and guidance cue throughout the nervous system.


Assuntos
Axônios , Cerebelo , Embrião de Galinha , Animais , Camundongos , Axônios/metabolismo , Cerebelo/metabolismo , Medula Espinal/metabolismo , Neurônios/metabolismo , Proteínas do Tecido Nervoso/genética , Precursores de Proteínas/metabolismo
4.
Mol Cell Neurosci ; 123: 103792, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36372157

RESUMO

The isolation of synaptoneurosomes (SNs) represents a useful means to study synaptic events. However, the size and density of synapses varies in different regions of the central nervous system (CNS), and this also depends on the experimental species studied, making it difficult to define a generic protocol for SNs preparation. To characterize synaptic failure in the spinal cord (SC) in the Tg-SOD1/G93A mouse model of amyotrophic lateral sclerosis (ALS), we applied a method we originally designed to isolate cortical and hippocampal SNs to SC tissue. Interestingly, we found that the SC SNs were isolated in a different gradient fraction to the cortical/hippocampal SNs. We compared the relative levels of synaptoneurosomal proteins in wild type (WT) animals, with control (Tg-SOD1) or Tg-SOD1/G93A mice at onset and those that were symptomatic using iTRAQ proteomics. The results obtained suggest that an important regulator of local synaptic translation, MNK1 (MAP kinase interacting serine/threonine kinase 1), might well influence the early stages of ALS.


Assuntos
Esclerose Amiotrófica Lateral , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Serina-Treonina Quinases , Animais , Camundongos , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/metabolismo , Modelos Animais de Doenças , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteômica , Medula Espinal/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo
5.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362341

RESUMO

Granzyme A (gzmA), a serine protease involved in the modulation of the inflammatory immune response, is found at an elevated level in the serum from ALS patients. However, the influence of gzmA on the progression of ALS remains unclear. The aim of our work was to assess whether the absence of gzmA in an ALS murine model could help slow down the progression of the disease. Homozygous and hemizygous gzmA-deficient mice expressing the hSOD1G93A transgene were generated, and survival of these mice was monitored. Subsequently, gene and protein expression of inflammatory and oxidative stress markers was measured in the spinal cord and quadriceps of these mice. We observed the longest lifespan in gzmA+/- mice. GzmA gene and protein expression was downregulated in the spinal cord and serum from gmzA+/- mice, confirming that the increased survival of hemizygous mice is correlated with lower levels of gzmA. In addition, mRNA and protein levels of glutathione reductase (GSR), involved in oxidative stress, were found downregulated in the spinal cord and quadriceps of gmzA+/- mice, together with lower IL-1ß and IL-6 mRNA levels in hemyzigous mice. In summary, our findings indicate for the first time that reduced levels, but not the absence, of gzmA could slightly ameliorate the disease progression in this animal model.


Assuntos
Esclerose Amiotrófica Lateral , Camundongos , Animais , Granzimas/metabolismo , Esclerose Amiotrófica Lateral/genética , Longevidade/genética , Medula Espinal/metabolismo , Modelos Animais de Doenças , Transgenes , RNA Mensageiro , Camundongos Transgênicos , Camundongos Endogâmicos C57BL , Superóxido Dismutase/genética
6.
Cell Physiol Biochem ; 56(6): 663-684, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36426390

RESUMO

The TWIK-related spinal cord K+ channel (TRESK) is part of the two-pore domain K+ channel family (K2P), which are also called leak potassium channels. As indicated by the channel family name, TRESK conducts K+ ions along the concentration gradient in a nearly voltage-independent manner leading to lowered membrane potentials. Although functional and pharmacological similarities exist, TRESK shows low sequence identity with other K2P channels. Moreover, the channel possesses several unique features such as its sensitivity to intracellular Ca2+ ions, that are not found in other K2P channels. High expression rates are found in immune-associated and neuronal cells, especially in sensory neurons of the dorsal root and trigeminal ganglia. As a consequence of the induced hyperpolarization, TRESK influences neuronal firing, the release of inflammatory mediators and the proliferation of distinct immune cells. Consequently, this channel might be a suitable target for pharmacological intervention in migraine, epilepsy, neuropathic pain or distinct immune diseases. In this review, we summarize the biochemical and biophysical properties of TRESK channels as well as their sensitivity to different known compounds. Furthermore, we give a structured overview about the physiological and pathophysiological impact of TRESK, that render the channel as an interesting target for specific drug development.


Assuntos
Canais de Potássio de Domínios Poros em Tandem , Potenciais da Membrana/fisiologia , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Neurônios/metabolismo , Medula Espinal/metabolismo
7.
Int J Mol Sci ; 23(22)2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36430896

RESUMO

To investigate a possible central mechanism of action of Botulinum toxin A (BoNT/A) following injection in the bladder, complementary to the acknowledged peripheral bladder effect, we studied changes in the expression of neuropeptides and receptors involved in lower urinary tract function in the spinal cord (SC) and dorsal root ganglia (DRG) of normal rats following BoNT/A bladder injection. Thirty-six Sprague-Dawley rats, divided into three groups of n = 12, received bladder injections of 2U or 5U OnabotulinumtoxinA (BOTOX®), or saline. Six animals from each group were sacrificed on days 7 and 14. Expression of Tachykinin 1 (Tac1), capsaicin receptor (TRPV1), neuropeptide Y (NPY), proenkephalin (PENK) and muscarinic receptors M1, M2, M3, was evaluated in the bladder, L6-S1 DRG, and SC segments using real-time PCR and Western blotting. Real-time PCR revealed increased expression of NPY in all tissues except for SC, and increased TRPV1 and PENK expression in DRG and SC, whereas expression of Tac1, M1 and M2 was decreased. Less significant changes were noted in protein levels. These findings suggest that bladder injections of OnabotulinumtoxinA may be followed by changes in the expression of sensory, sympathetic and cholinergic bladder function regulators at the DRG/SC level.


Assuntos
Toxinas Botulínicas Tipo A , Animais , Ratos , Toxinas Botulínicas Tipo A/farmacologia , Bexiga Urinária/metabolismo , Ratos Sprague-Dawley , Gânglios Espinais/metabolismo , Medula Espinal/metabolismo
8.
Prog Mol Biol Transl Sci ; 193(1): 99-117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36357081

RESUMO

Pain sensation is a normal physiological response to alert and prevent further tissue damage. It involves the perception of external stimuli by somatosensory neurons, then transmission of the message to various other types of neurons present in the spinal cord and brain to generate an appropriate response. Currently available analgesics exhibit very modest efficacy, and that too in only a subset of patients with chronic pain conditions, particularly neuropathic pain. The G protein-coupled receptors (GPCRs) are expressed on presynaptic, postsynaptic terminals, and soma of somatosensory neurons, which binds to various types of ligands to modulate neuronal activity and thus pain sensation in both directions. Fundamentally, neuropathic pain arises due to aberrant neuronal plasticity, which includes the sensitization of peripheral primary afferents (dorsal root ganglia and trigeminal ganglia) and the sensitization of central nociceptive neurons in the spinal cord or trigeminal nucleus or brain stem and cortex. Owing to the expression profiles of GPCRs in somatosensory neurons and other neuroanatomical regions involved in pain processing and transmission, this article shall focus only on four families of GPCRs: 1- Opioid receptors, 2-Cannabinoid receptors, 3-Adenosine receptors, and 4-Chemokine receptors.


Assuntos
Neuralgia , Humanos , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Gânglios Espinais/metabolismo , Medula Espinal/metabolismo , Neurônios/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
9.
Neurol India ; 70(Supplement): S288-S295, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36412383

RESUMO

Background: There is an urgent clinical need to provide a theoretical basis for silver needle thermal therapy to Myofacial pain syndrome (MPS). Objective: This study was conducted to explore the effect of silver needle thermal therapy on myofascial pain syndrome in rats. Methods: MPS rat models were duplicated, and the rats were subsequently divided into model and treatment groups. A normal control group was synchronously set up. No treatment was given to the model group, whereas silver needle thermal therapy was administered to the treatment group. The thermal and mechanical pain threshold, the morphological structure as well as the expression of 5-HT3 receptors in the spinal cord were observed. Results: Rats from the treatment group presented with a significantly higher pain threshold compared to the untreated model group.The myofascial arrangement of the affected part of the model group was disordered, and some muscle fibers were atrophied and deformed. Meanwhile, the myofascial arrangement of the treatment group became more regular than that of the model group. The expression levels of 5-HT3 receptor in the spinal cord of the untreated model group were significantly increased, while being markedly decreased in the treatment group. Conclusions: Silver needle thermal therapy can augment the pain threshold of rats with MPS, repair the damaged myofascial membrane in the rats, and further reduce the expression of 5-HT3 receptors in the spinal cord of the MPS rats.


Assuntos
Síndromes da Dor Miofascial , Receptores 5-HT3 de Serotonina , Ratos , Animais , Receptores 5-HT3 de Serotonina/metabolismo , Prata/metabolismo , Síndromes da Dor Miofascial/metabolismo , Dor , Medula Espinal/metabolismo
10.
Basic Res Cardiol ; 117(1): 56, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36367592

RESUMO

Astrocytes play a key role in the response to injury and noxious stimuli, but its role in myocardial ischemia-reperfusion (I/R) injury remains largely unknown. Here we determined whether manipulation of spinal astrocyte activity affected myocardial I/R injury and the underlying mechanisms. By ligating the left coronary artery to establish an in vivo I/R rat model, we observed a 1.7-fold rise in glial fibrillary acidic protein (GFAP) protein level in spinal cord following myocardial I/R injury. Inhibition of spinal astrocytes by intrathecal injection of fluoro-citrate, an astrocyte inhibitor, decreased GFAP immunostaining and reduced infarct size by 29% relative to the I/R group. Using a Designer Receptor Exclusively Activated by Designer Drugs (DREADD) chemogenetic approach, we bi-directionally manipulated astrocyte activity employing GFAP promoter-driven Gq- or Gi-coupled signaling. The Gq-DREADD-mediated activation of spinal astrocytes caused transient receptor potential vanilloid 1 (TRPV1) activation and neuropeptide release leading to a 1.3-fold increase in infarct size, 1.2-fold rise in serum norepinephrine level and higher arrhythmia score relative to I/R group. In contrast, Gi-DREADD-mediated inhibition of spinal astrocytes suppressed TRPV1-mediated nociceptive signaling, resulting in 35% reduction of infarct size and 51% reduction of arrhythmia score from I/R group, as well as lowering serum norepinephrine level from 3158 ± 108 to 2047 ± 95 pg/mL. Further, intrathecal administration of TRPV1 or neuropeptide antagonists reduced infarct size and serum norepinephrine level. These findings demonstrate a functional role of spinal astrocytes in myocardial I/R injury and provide a novel potential therapeutic approach targeting spinal cord astrocytes for the prevention of cardiac injury.


Assuntos
Traumatismo por Reperfusão Miocárdica , Ratos , Animais , Traumatismo por Reperfusão Miocárdica/metabolismo , Astrócitos/metabolismo , Medula Espinal/metabolismo , Arritmias Cardíacas , Infarto/metabolismo , Norepinefrina
11.
J Neuroinflammation ; 19(1): 266, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333772

RESUMO

BACKGROUND: Immune cells play crucial roles after spinal cord injury (SCI). However, incomplete knowledge of immune contributions to injury and repair hinders development of SCI therapies. We leveraged single-cell observations to describe key populations of immune cells present in the spinal cord and changes in their transcriptional profiles from uninjured to subacute and chronic stages of SCI. METHODS: Deep-read single-cell sequencing was performed on CD45+ cells from spinal cords of uninjured and injured Swiss-webster mice. After T9 thoracic contusion, cells were collected 3-, 7-, and 60-day post-injury (dpi). Subpopulations of CD45+ immune cells were identified informatically, and their transcriptional responses characterized with time. We compared gene expression in spinal cord microglia and B cell subpopulations with those in published models of disease and injury. Microglia were compared with Disease Associated Microglia (DAM) and Injury Responsive Microglia (IRM). B cells were compared to developmental lineage states and to an Amyotrophic Lateral Sclerosis (ALS) model. RESULTS: In uninjured and 7 dpi spinal cord, most CD45+ cells isolated were microglia while chronically B cells predominated. B cells accumulating in the spinal cord following injury included immature B to mature stages and were predominantly found in the injury zone. We defined diverse subtypes of microglia and B cells with altered gene expression with time after SCI. Spinal cord microglia gene expression indicates differences from brain microglia at rest and in inflammatory states. Expression analysis of signaling ligand-receptor partners identified microglia-B cell interactions at acute and chronic stages that may be involved in B cell recruitment, retention, and formation of ectopic lymphoid follicles. CONCLUSIONS: Immune cell responses to SCI have region-specific aspects and evolve with time. Developmentally diverse populations of B cells accumulate in the spinal cord following injury. Microglia at subacute stages express B cell recruitment factors, while chronically, they express factors predicted to reduce B cell inflammatory state. In the injured spinal cord, B cells create ectopic lymphoid structures, and express secreted factors potentially acting on microglia. Our study predicts previously unidentified crosstalk between microglia and B cells post-injury at acute and chronic stages, revealing new potential targets of inflammatory responses for SCI repair warranting future functional analyses.


Assuntos
Microglia , Traumatismos da Medula Espinal , Camundongos , Animais , Microglia/metabolismo , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , Linfócitos B/metabolismo
12.
Mol Pain ; 18: 17448069221135743, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-36227008

RESUMO

Bone cancer pain (BCP) is a clinically intractable mixed pain, involving inflammation and neuropathic pain, and its mechanisms remain unclear. CXC chemokine receptor 1 (CXCR1, IL-8RA) and 2 (CXCR2, IL-8RB) are high-affinity receptors for interleukin 8 (IL8). According to previous studies, CXCR2 plays a crucial role in BCP between astrocytes and neurons, while the role of CXCR1 remains unclear. The objective of this study was to investigate the role of CXCR1 in BCP. We found that CXCR1 expression increased in the spinal dorsal horn. Intrathecal injection of CXCR1 siRNA effectively attenuated mechanical allodynia and pain-related behaviors in rats. It was found that CXCR1 was predominantly co-localized with neurons. Intrathecal injection of CXCR1-siRNA reduced phosphorylated JAK2/STAT3 protein levels and the NLRP3 inflammasome (NLRP3, caspase1, and IL-1ß) levels. Furthermore, in vitro cytological experiments confirmed this conclusion. The study results suggest that the spinal chemokine receptor CXCR1 activation mediates BCP through JAK2/STAT3 signaling pathway and NLRP3 inflammasome (NLRP3, caspase1, and IL-1ß).


Assuntos
Neoplasias Ósseas , Dor do Câncer , Neuralgia , Ratos , Feminino , Animais , Receptores de Interleucina-8A/genética , Receptores de Interleucina-8A/metabolismo , Dor do Câncer/etiologia , Dor do Câncer/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , RNA Interferente Pequeno/metabolismo , Neoplasias Ósseas/complicações , Neoplasias Ósseas/metabolismo , Receptores de Interleucina-8B/metabolismo , Neuralgia/metabolismo , Medula Espinal/metabolismo
13.
Br J Anaesth ; 129(6): 959-969, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36243579

RESUMO

BACKGROUND: Repetitive opioid use does not always alleviate basal pain, procedural pain, or both after burn injury. Mitigation of burn injury-site pain can be achieved by GTS-21 stimulation of α7-acetylcholine nicotinic receptors (α7AChRs) and reduced microglia activation in rat. We tested the hypothesis that morphine exaggerates burn injury-site pain and GTS-21 alleviates both morphine-induced aggravated burn injury pain and microglia activation. METHODS: Young rats with dorsal paw burn injury or sham-burn received intraperitoneal saline, morphine, GTS-21, or a combination twice daily for 14 days. Ipsilateral plantar pain thresholds were tested every other day before morning drugs from days 0-20. Spinal microglia activation, evidenced as pain-transducer (tumour necrosis factor-α [TNF-α], interleukin [IL]-6, IL-1ß, nuclear factor kappa B [NF-κB], Toll-like receptor 4 [TLR4]) expression, was examined using immunohistochemistry and immunoblot. In cultured microglia, morphine-induced cytokine expression was measured (quantitative polymerase chain reaction/enzyme-linked immunosorbent assay [qPCR/ELISA]). RESULTS: Morphine aggravated allodynia at day 5 in sham-burn (P=0.039, n=8-11) but significantly aggravated burn injury site allodynia by day 3 (P=0.010, n=8-11). Microgliosis paralleled nociceptive behaviour changes where burn injury with morphine had highest microgliosis compared with burn injury, morphine alone, or controls (number of cells per field [SD]: 33.8 [2.4], 18.0 [4.1], 8.2 [1.9], and 4.8 [2.0], respectively; P<0.001, n=4-5]. GTS-21 reversed the morphine-induced pain component in sham-burn and burn injury rats together with reduced microgliosis and spinal pain-transducer expression (TNF-α, IL-6, IL-1ß, NF-κB, and TLR4). Morphine-exposed microglial cells showed increased cytokine expression, which was mitigated by GTS-21. CONCLUSIONS: Morphine or burn injury alone increases pain together with microgliosis and pain-transducer expression. Morphine administration augments burn injury-site nociception sooner and aggravated spinal microgliosis and inflammatory pain-transducer expression. GTS-21 has the potential to treat morphine-induced pain in burn injury.


Assuntos
Queimaduras , Morfina , Animais , Ratos , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/uso terapêutico , Queimaduras/complicações , Queimaduras/tratamento farmacológico , Agonistas Colinérgicos/metabolismo , Hiperalgesia/induzido quimicamente , Microglia/metabolismo , NF-kappa B/metabolismo , NF-kappa B/uso terapêutico , Dor/tratamento farmacológico , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/uso terapêutico , Fator de Necrose Tumoral alfa
14.
J Am Heart Assoc ; 11(20): e026076, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36216458

RESUMO

Background Spinal cord ischemia (SCI) remains a devastating complication after aortic dissection or repair. A primary hypoxic damage is followed by a secondary damage resulting in further cellular loss via apoptosis. Affected patients have a poor prognosis and limited therapeutic options. Shock wave therapy (SWT) improves functional outcome, neuronal degeneration and survival in murine spinal cord injury. In this first-in-human study we treated 5 patients with spinal cord ischemia with SWT aiming to prove safety and feasibility. Methods and Results Human neurons were subjected to ischemic injury with subsequent SWT. Reactive oxygen species and cellular apoptosis were quantified using flow cytometry. Signaling of the antioxidative transcription factor NRF2 (nuclear factor erythroid 2-related factor 2) and immune receptor Toll-like receptor 3 (TLR3) were analyzed. To assess whether SWT act via a conserved mechanism, transgenic tlr3-/- zebrafish created via CRISPR/Cas9 were subjected to spinal cord injury. To translate our findings into a clinical setting, 5 patients with SCI underwent SWT. Baseline analysis and follow-up (6 months) included assessment of American Spinal Cord Injury Association (ASIA) impairment scale, evaluation of Spinal Cord Independence Measure score and World Health Organization Quality of Life questionnaire. SWT reduced the number of reactive oxygen species positive cells and apoptosis upon ischemia via induction of the antioxidative factor nuclear factor erythroid 2-related factor 2. Inhibition or deletion of tlr3 impaired axonal growth after spinal cord lesion in zebrafish, whereas tlr3 stimulation enhanced spinal regeneration. In a first-in-human study, we treated 5 patients with SCI using SWT (mean age, 65.3 years). Four patients presented with acute aortic dissection (80%), 2 of them exhibited preoperative neurological symptoms (40%). Impairment was ASIA A in 1 patient (20%), ASIA B in 3 patients (60%), and ASIA D in 1 patient (20%) at baseline. At follow-up, 2 patients were graded as ASIA A (40%) and 3 patients as ASIA B (60%). Spinal cord independence measure score showed significant improvement. Examination of World Health Organization Quality of Life questionnaires revealed increased scores at follow-up. Conclusions SWT reduces oxidative damage upon SCI via immune receptor TLR3. The first-in-human application proved safety and feasibility in patients with SCI. SWT could therefore become a powerful regenerative treatment option for this devastating injury.


Assuntos
Aneurisma Dissecante , Tratamento por Ondas de Choque Extracorpóreas , Traumatismos da Medula Espinal , Isquemia do Cordão Espinal , Humanos , Camundongos , Animais , Idoso , Receptor 3 Toll-Like/metabolismo , Receptor 3 Toll-Like/uso terapêutico , Fator 2 Relacionado a NF-E2 , Peixe-Zebra , Estudos de Viabilidade , Espécies Reativas de Oxigênio , Qualidade de Vida , Isquemia do Cordão Espinal/etiologia , Isquemia do Cordão Espinal/prevenção & controle , Isquemia do Cordão Espinal/patologia , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Medula Espinal/metabolismo , Estresse Oxidativo , Isquemia , Aneurisma Dissecante/patologia
15.
Neurogastroenterol Motil ; 34(11): e14441, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36239298

RESUMO

BACKGROUND: Persistent visceral hypersensitivity is a key component of functional and inflammatory gastrointestinal diseases. Current animal models fail to fully reproduce the characteristics of visceral pain in humans, particularly as it relates to persistent hypersensitivity. This work explores the validity of DSS-induced colitis in rats as a model to mimic chronic intestinal hypersensitivity. METHODS: Exposure to DSS (5% for 7 days) was used to induce colitis in rats. Thereafter, changes in viscerosensitivity (visceromotor responses to colorectal distension-CRD), the presence of somatic referred pain (mechanosensitivity of the hind paws, von Frey test) and the expression (qRT-PCR) of sensory-related markers (colon, lumbosacral DRGs, and lumbosacral spinal cord) were assessed at different times during the 35 days period after colitis induction. RESULTS: Following colitis, a sustained increase in visceromotor responses to CRD were observed, indicative of the presence of visceral hypersensitivity. Responses in animals without colitis remained stable over time. In colitic animals, somatic referred hypersensitivity was also detected. DSS-induced colitis was associated to a differential expression of sensory-related markers (with both pro- and anti-nociceptive action) in the colon, lumbosacral DRGs and lumbosacral spinal cord; indicating the presence of peripheral and central sensitization. CONCLUSIONS AND INFERENCES: DSS-induced colitis in rats is associated to the generation of a long-lasting state of visceral (colonic) hypersensitivity, despite clinical colitis resolution. This model reproduces the changes in intestinal sensitivity characteristics of inflammatory and functional gastrointestinal disorders in humans and can be used in the characterization of new pharmacological treatments against visceral pain.


Assuntos
Colite , Dor Visceral , Animais , Colo/metabolismo , Modelos Animais de Doenças , Humanos , Ratos , Medula Espinal/metabolismo
16.
Bull Exp Biol Med ; 173(5): 590-593, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36210424

RESUMO

We performed a quantitative study of the neuronal population in the spinal cord of mice with acute and chronic model of experimental autoimmune encephalomyelitis. Immunohistological/immunofluorescent analysis with motor neuron marker ChAT revealed a significant decrease in the number of motor neurons in the ventral horns of the lumbar spinal cord in the acute form of autoimmune encephalomyelitis, with the further appearance of large empty (containing no motor neurons) areas in the ventral horns in the chronic form. The development of experimental autoimmune encephalomyelitis is accompanied by degradation and death of neurons, in particular ChAT+ motor neurons.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Encefalomielite Autoimune Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios Motores/metabolismo , Medula Espinal/metabolismo
17.
J Neuroinflammation ; 19(1): 254, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36217203

RESUMO

BACKGROUND: Neuropathic pain is experienced worldwide by patients suffering from nerve injuries, infectious or metabolic diseases or chemotherapy. However, the treatment options are still limited because of low efficacy and sometimes severe side effects. Recently, the deficiency of FKBP51 was shown to relieve chronic pain, revealing FKBP51 as a potential therapeutic target. However, a specific and potent FKBP51 inhibitor was not available until recently which hampered targeting of FKBP51. METHODS: In this study, we used the well-established and robust spared nerve injury model to analyze the effect of SAFit2 on nerve injury-induced neuropathic pain and to elucidate its pharmacodynamics profile. Therefore, the mice were treated with 10 mg/kg SAFit2 after surgery, the mice behavior was assessed over 21 days and biochemical analysis were performed after 14 and 21 days. Furthermore, the impact of SAFit2 on sensory neurons and macrophages was investigated in vitro. RESULTS: Here, we show that the FKBP51 inhibitor SAFit2 ameliorates nerve injury-induced neuropathic pain in vivo by reducing neuroinflammation. SAFit2 reduces the infiltration of immune cells into neuronal tissue and counteracts the increased NF-κB pathway activation which leads to reduced cytokine and chemokine levels in the DRGs and spinal cord. In addition, SAFit2 desensitizes the pain-relevant TRPV1 channel and subsequently reduces the release of pro-inflammatory neuropeptides from sensory neurons. CONCLUSIONS: SAFit2 ameliorates neuroinflammation and counteracts enhanced neuronal activity after nerve injury leading to an amelioration of nerve injury-induced neuropathic pain. Based on these findings, SAFit2 constitutes as a novel and promising drug candidate for the treatment of nerve injury-induced neuropathic pain.


Assuntos
Neuralgia , Neuropeptídeos , Traumatismos dos Nervos Periféricos , Animais , Citocinas/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Camundongos , NF-kappa B/metabolismo , Neuralgia/tratamento farmacológico , Neuralgia/etiologia , Neuralgia/metabolismo , Doenças Neuroinflamatórias , Neuropeptídeos/metabolismo , Traumatismos dos Nervos Periféricos/metabolismo , Medula Espinal/metabolismo
18.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36232433

RESUMO

Spasticity impacts the quality of life of patients suffering spinal cord injury and impedes the recovery of locomotion. At the cellular level, spasticity is considered to be primarily caused by the hyperexcitability of spinal α-motoneurons (MNs) within the spinal stretch reflex circuit. Here, we hypothesized that after a complete spinal cord transection in rats, fast adaptive molecular responses of lumbar MNs develop in return for the loss of inputs. We assumed that early loss of glutamatergic afferents changes the expression of glutamatergic AMPA and NMDA receptor subunits, which may be the forerunners of the developing spasticity of hindlimb muscles. To better understand its molecular underpinnings, concomitant expression of GABA and Glycinergic receptors and serotoninergic and noradrenergic receptors, which regulate the persistent inward currents crucial for sustained discharges in MNs, were examined together with voltage-gated ion channels and cation-chloride cotransporters. Using quantitative real-time PCR, we showed in the tracer-identified MNs innervating extensor and flexor muscles of the ankle joint multiple increases in transcripts coding for AMPAR and 5-HTR subunits, along with a profound decrease in GABAAR, GlyR subunits, and KCC2. Our study demonstrated that both MNs groups similarly adapt to a more excitable state, which may increase the occurrence of extensor and flexor muscle spasms.


Assuntos
Traumatismos da Medula Espinal , Simportadores , Animais , Cloretos/metabolismo , Neurônios Motores/metabolismo , Espasticidade Muscular/metabolismo , Fenótipo , Qualidade de Vida , Ratos , Receptores de N-Metil-D-Aspartato/metabolismo , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Simportadores/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/metabolismo , Ácido gama-Aminobutírico/metabolismo
19.
Bull Exp Biol Med ; 173(5): 594-601, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36214984

RESUMO

We studied the interaction between glucocorticoid receptor (GR) and HCN4 channels in the rat model of spared nerve injury (SNI) in Sprague-Dawley rats (n=124). The animals were randomly divided into 6 groups: sham-operated (SO; n=24), SNI (reference group; n=20), and 4 experimental SNI groups intrathecally treated with dexamethasone (DEX; GR agonist; n=20), RU38486 (GR antagonist; n=20), ZD7288 (HCN channels blocker; n=20), and ZD7288+DEX (n=20). The paw mechanical withdrawal threshold (PWT) was measured one day before surgery (SO group) and on days 1, 3, 7, 14, and 21 after surgery. Behavioral results showed that mechanical hyperalgesia appeared on day 1 after SNI, while PWT decreased gradually with time. The expression of GR and HCN4 channels in L4-L6 dorsal horn of the spinal cord was detected by Western blotting and immunohistochemistry. In the reference group, SNI significantly increased GR expression up to day 14 after surgery in comparison with the SO group. The expression of GR showed a tendency to increase in the DEX group (with the maximum expression on days 14 and 21), significantly increased in the RU38486 group (maximum on day 7). In the ZD7288 group, GR expression was lower than in the SNI group and did not change throughout the experiment, suggesting that ZD7288 could block the expression of GR. In the DEX group, the expression of HCN4 channels was significantly higher on day 1 after SNI, but there were no differences in this parameter between the RU38486 and ZD7288 groups. In the ZD7288+DEX group, the expression of HCN4 channels significantly increased on days 14 and 21 after SNI. Thus, GR and HCN4 have the same linkage in the formation of central sensitization after SNI, but antagonists have no significant effect on the improvement of pain behavior.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Animais , Dexametasona/farmacologia , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Mifepristona/farmacologia , Neuralgia/tratamento farmacológico , Traumatismos dos Nervos Periféricos/complicações , Traumatismos dos Nervos Periféricos/tratamento farmacológico , Traumatismos dos Nervos Periféricos/metabolismo , Canais de Potássio/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Medula Espinal/metabolismo , Corno Dorsal da Medula Espinal/metabolismo
20.
Carbohydr Polym ; 298: 120047, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241313

RESUMO

Spinal cord injury (SCI) decreases people's both physical and psychological levels. The rehabilitation of SCI is still a clinical challenging process owing to the inflammatory environment for cell survival. Herein, we designed a dopamine-modified chitosan hydrogel to improve poor microenvironment of spinal cord injury. Dopamine modified chitosan hydrogel was fabricated by crosslinking with citric acid (CS-CA-DA), which address the insufficient mechanical properties. In vitro analysis showed that dopamine modification improved the cell survival and cell adhesion. Moreover, implantation of CS-CA-DA hydrogel alone into rat injured spinal cord helped improving cell survivals, modulating immunity, promoting macrophage polarization to the M2 phenotype and promoting axonal regeneration in vivo in brutal areas of SCI. This strategy of modified chitosan with dopamine undergoing a high mechanical properties, excellent cell compatibility and antioxidant performance, providing a new insight into repairing spinal cord injury.


Assuntos
Quitosana , Traumatismos da Medula Espinal , Animais , Antioxidantes , Ácido Cítrico , Dopamina , Hidrogéis , Ratos , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo
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