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Despite widespread adoption of tissue clearing techniques in recent years, poor access to suitable light-sheet fluorescence microscopes remains a major obstacle for biomedical end-users. Here, we present descSPIM (desktop-equipped SPIM for cleared specimens), a low-cost ($20,000-50,000), low-expertise (one-day installation by a non-expert), yet practical do-it-yourself light-sheet microscope as a solution for this bottleneck. Even the most fundamental configuration of descSPIM enables multi-color imaging of whole mouse brains and a cancer cell line-derived xenograft tumor mass for the visualization of neurocircuitry, assessment of drug distribution, and pathological examination by false-colored hematoxylin and eosin staining in a three-dimensional manner. Academically open-sourced ( https://github.com/dbsb-juntendo/descSPIM ), descSPIM allows routine three-dimensional imaging of cleared samples in minutes. Thus, the dissemination of descSPIM will accelerate biomedical discoveries driven by tissue clearing technologies.
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Encéfalo , Imageamento Tridimensional , Microscopia de Fluorescência , Animais , Camundongos , Encéfalo/diagnóstico por imagem , Humanos , Microscopia de Fluorescência/métodos , Microscopia de Fluorescência/instrumentação , Imageamento Tridimensional/métodos , Linhagem Celular TumoralRESUMO
Adult stem cells not only maintain tissue homeostasis but are also critical for tissue regeneration during injury. Skeletal stem cells are multipotent stem cells that can even generate bones and cartilage upon transplantation to an ectopic site. This tissue generation process requires essential stem cell characteristics including self-renewal, engraftment, proliferation, and differentiation in the microenvironment. Our research team has successfully characterized and isolated skeletal stem cells (SSCs) from the cranial suture called suture stem cells (SuSCs), which are responsible for craniofacial bone development, homeostasis, and injury-induced repair. To assess their stemness features, we have demonstrated the use of kidney capsule transplantation for an in vivo clonal expansion study. The results show bone formation at a single-cell level, thus permitting a faithful assessment of stem cell numbers at the ectopic site. The sensitivity in assessing stem cell presence permits using kidney capsule transplantation to determine stem cell frequency by limiting dilution assay. Here, we described detailed protocols for kidney capsule transplantation and limiting dilution assay. These methods are extremely valuable both for the evaluation of skeletogenic ability and the determination of stem cell frequency.
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OBJECTIVES: The strategy of identifying stigmata of recent hemorrhage (SRH) and treating the bleeding source is important for the prevention of rebleeding in colonic diverticular hemorrhage (CDH). However, there are few known reports on SRH identification thus far. This large multicenter study evaluated factors correlated with SRH identification, including observation time during colonoscopy. METHODS: A total of 392 CDH cases were classified into presumptive CDH (n = 276) or definitive CDH with SRH (n = 116) on the basis of colonoscopy results. Multivariate Cox proportional hazards regression was employed to identify factors correlated with SRH identification. For the endoscopic treatment, endoscopic clips (EC), endoscopic band ligation (EBL) or endoscopic detachable snare ligation (EDSL) was performed. RESULTS: Longer observation time was significantly correlated with SRH identification in multivariate analysis (OR, 10.3 [95% CI: 3.84-27.9], p<.001). Receiver operating characteristic curve (ROC) analysis of the SRH identification rate by observation time indicated a high area under the curve (AUC) (0.79), and the threshold of the observation time was calculated at 19 min using Youden's index. Moreover, the patients taken endoscopic hemostasis showed significantly lower early rebleeding rate than patients without endoscopic hemostasis (16.4% vs. 31.9%, p=.001), suggesting the importance of identifying SRH and treating the bleeding source for reducing the risk of recurrent bleeding. CONCLUSIONS: Long-observation time correlated with SRH identification in this study, in which bowel preparation and water-jet scope and cap attachment are commonly used. This is the first known study to highlight the significance of observation time in the SRH identification rates.
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Doenças do Colo , Divertículo do Colo , Hemostase Endoscópica , Humanos , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Colonoscopia/métodos , Divertículo do Colo/complicações , Divertículo do Colo/terapia , Doenças do Colo/terapia , Hemostase Endoscópica/métodosRESUMO
Many patients treated for head and neck cancers experience salivary gland hypofunction due to radiation damage. Understanding the mechanisms of cellular damage induced by radiation treatment is important in order to design methods of radioprotection. In addition, it is crucial to recognize the indirect effects of irradiation and the systemic responses that may alter saliva secretion. In this study, radiation was delivered to murine submandibular glands (SMGs) bilaterally, using a 137Cs gamma ray irradiator, or unilaterally, using a small-animal radiation research platform (SARRP). Analysis at 3, 24 and 48â h showed dynamic changes in mRNA and protein expression in SMGs irradiated bilaterally. Unilateral irradiation using the SARRP caused similar changes in the irradiated SMGs, as well as significant off-target, bystander effects in the non-irradiated contralateral SMGs.
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Radioisótopos de Césio , Glândula Submandibular , Camundongos , Animais , Glândula Submandibular/metabolismo , Glândula Submandibular/efeitos da radiação , Radioisótopos de Césio/metabolismo , Efeito Espectador , Salivação/efeitos da radiaçãoRESUMO
Receptor transporter protein 4 (RTP4), one of the receptor chaperone proteins, contributes to the maturation and membrane trafficking of opioid receptor heteromers consisting of mu (MOPr) and delta (DOPr) opioid receptors (MOPr-DOPr). Although MOPr-DOPr is known to mediate the development of morphine tolerance, the extent to which RTP4 plays a role in this process has not been elucidated. Given that RTP4 can be upregulated by repeated administration of morphine, especially in the hypothalamus, here we investigated the effect of hypothalamus-selective ablation of RTP4 on the development of antinociceptive tolerance to morphine. In this study, we generated RTP4flox mice and selectively knocked-out RTP4 using local injection of adeno-associated virus expressing Cre recombinase (AAV-Cre) into the hypothalamus. The AAV-Cre injection partially, but significantly, decreased the level of RTP4 expression, and suppressed the development of antinociceptive tolerance to morphine. Next, we examined the mechanism of regulation of RTP4 and found that, in neuronal cells, Rtp4 induction is via Gi and MAPK activation, while, in microglial cells, the induction is via Toll-like receptor 4. Together, these studies highlight the role of MOR activity in regulating RTP4, which, in turn, plays an important role in modulating morphine effects in vivo.
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Morfina , Receptor 4 Toll-Like , Camundongos , Animais , Morfina/farmacologia , Receptor 4 Toll-Like/metabolismo , Receptores Opioides mu/metabolismo , Analgésicos Opioides/farmacologia , Receptores Opioides/metabolismo , Hipotálamo/metabolismo , Chaperonas Moleculares/metabolismoRESUMO
Gastrointestinal involvement is a rare manifestation of systemic amyloidosis, and few reports have been published on localized amyloidosis of the colon. Only one case report has been published on the long-term prognosis of localized colorectal amyloidosis, and there are no previous reports on localized colorectal ATTR amyloidosis. Here, we report an 80-year-old male with localized colorectal wild-type ATTR amyloidosis who presented with edematous mucosa with vascular changes throughout the colon. He did not exhibit any symptoms or endoscopic exacerbation for 8 years after diagnosis. However, after 8 years, he developed early stage colorectal cancer and cytomegalovirus-associated ulcer. He was treated with endoscopic submucosal dissection, which was relatively challenging due to his hemorrhagic condition and poor elevation of the submucosa caused by amyloid deposits. Since the tumor was completely resected, he will undergo regular follow-up. Our review of 20 previous cases of localized colorectal amyloidosis revealed its clinical features and long-term prognosis. Specifically, ours is the second case of a diffuse pan-colon type of colorectal localized amyloidosis, which may lead to various complications, such as colorectal cancer, over a long period of time, and thus, regular follow-up is necessary.
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Amiloidose , Neoplasias Colorretais , Infecções por Citomegalovirus , Idoso de 80 Anos ou mais , Amiloidose/complicações , Amiloidose/diagnóstico , Neoplasias Colorretais/complicações , Neoplasias Colorretais/cirurgia , Infecções por Citomegalovirus/complicações , Seguimentos , Humanos , Masculino , ÚlceraRESUMO
Progress in the development of salivary gland regenerative strategies is limited by poor maintenance of the secretory function of salivary gland cells (SGCs) in vitro. To reduce the precipitous loss of secretory function, a modified approach to isolate intact acinar cell clusters and intercalated ducts (AIDUCs), rather than commonly used single cell suspension, is investigated. This isolation approach yields AIDUCs that maintain many of the cell-cell and cell-matrix interactions of intact glands. Encapsulation of AIDUCs in matrix metalloproteinase (MMP)-degradable PEG hydrogels promotes self-assembly into salivary gland mimetics (SGm) with acinar-like structure. Expression of Mist1, a transcription factor associated with secretory function, is detectable throughout the in vitro culture period up to 14 days. Immunohistochemistry also confirms expression of acinar cell markers (NKCC1, PIP and AQP5), duct cell markers (K7 and K5), and myoepithelial cell markers (SMA). Robust carbachol and ATP-stimulated calcium flux is observed within the SGm for up to 14 days after encapsulation, indicating that secretory function is maintained. Though some acinar-to-ductal metaplasia is observed within SGm, it is reduced compared to previous reports. In conclusion, cell-cell interactions maintained within AIDUCs together with the hydrogel microenvironment may be a promising platform for salivary gland regenerative strategies.
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Células Acinares , Hidrogéis , Células Acinares/metabolismo , Hidrogéis/metabolismo , Metaloproteinases da Matriz/metabolismo , Glândulas Salivares/metabolismoRESUMO
Radiation therapy for head and neck cancers causes salivary gland dysfunction leading to permanent xerostomia. Limited progress in the discovery of new therapeutic strategies is attributed to the lack of in vitro models that mimic salivary gland function and allow high-throughput drug screening. We address this limitation by combining engineered extracellular matrices with microbubble (MB) array technology to develop functional tissue mimetics for mouse and human salivary glands. We demonstrate that mouse and human salivary tissues encapsulated within matrix metalloproteinase-degradable poly(ethylene glycol) hydrogels formed in MB arrays are viable, express key salivary gland markers, and exhibit polarized localization of functional proteins. The salivary gland mimetics (SGm) respond to calcium signaling agonists and secrete salivary proteins. SGm were then used to evaluate radiosensitivity and mitigation of radiation damage using a radioprotective compound. Altogether, SGm exhibit phenotypic and functional parameters of salivary glands, and provide an enabling technology for high-content/throughput drug testing.
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Células Acinares/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Lesões por Radiação/prevenção & controle , Glândulas Salivares/efeitos dos fármacos , Análise Serial de Tecidos , Xerostomia/prevenção & controle , Células Acinares/metabolismo , Células Acinares/efeitos da radiação , Animais , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Hidrogéis , Masculino , Camundongos Endogâmicos C57BL , Microbolhas , Pessoa de Meia-Idade , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/metabolismo , Glândula Parótida/efeitos da radiação , Fenótipo , Polietilenoglicóis/química , Lesões por Radiação/etiologia , Lesões por Radiação/metabolismo , Glândulas Salivares/metabolismo , Glândulas Salivares/efeitos da radiação , Xerostomia/etiologia , Xerostomia/metabolismoRESUMO
Ulcerative colitis (UC) is an inflammatory bowel disease that causes chronic inflammation in the colon. 5-aminosalicylic acid and immunosuppressive medications such as corticosteroids, immunomodulators, and biologic agents are used to treat these patients. However, patients with UC who receive immunosuppressive medications may be at risk for certain opportunistic infections. Epstein-Barr virus (EBV) is one of those opportunistic infections, and its pathogenic role has been implicated in refractory UC, but its pathogenicity should be further investigated. Here, we report a surgical case of refractory UC that demonstrated a serologically post-infected pattern of EBV at admission but that later had a high load of EBV in both the peripheral blood and colonic mucosa. These findings suggest that EBV may have been reactivated in the colon, after which it damaged the colonic mucosa and aggravated inflammation in this patient with UC. Thus, EBV might lead to severity and a refractory response against corticosteroids and anti-TNFα agents, necessitating emergency surgery. Viral surveillance for EBV in patients with refractory UC may facilitate understanding of the patient's pathophysiology and predicting response to medications, and the development of antiviral intervention for those patients may improve their prognosis.
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Colite Ulcerativa , Infecções por Vírus Epstein-Barr , Doenças Inflamatórias Intestinais , Colite Ulcerativa/complicações , Colite Ulcerativa/tratamento farmacológico , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , HumanosRESUMO
Treatment of fibromyalgia is an unmet medical need; however, its pathogenesis is still poorly understood. In a series of studies, we have demonstrated that some pharmacological treatments reverse generalized chronic pain but do not affect the lack of morphine analgesia in the intermittent cold stress (ICS)-induced fibromyalgia-like pain model in mice. Here we report that repeated intraperitoneal treatments with mirtazapine, which is presumed to disinhibit 5-hydroxytriptamine (5-HT) release and activate 5-HT1 receptor through mechanisms of blocking presynaptic adrenergic α2 and postsynaptic 5-HT2 and 5-HT3 receptors, completely reversed the chronic pain for more than 4 to 5 days after the cessation of treatments. The repeated mirtazapine treatments also recovered the morphine analgesia after the return of nociceptive threshold to the normal level. The microinjection of small interfering RNA (siRNA) adrenergic α2a receptor (ADRA2A) into the habenula, which showed a selective upregulation of α2 receptor gene expression after ICS, reversed the hyperalgesia but did not recover the morphine analgesia. However, both reversal of hyperalgesia and recovery of morphine analgesia were observed when siRNA ADRA2A was administered intracerebroventricularly. As the habenular is reported to be involved in the emotion/reward-related pain and hypoalgesia, these results suggest that mirtazapine could attenuate pain and/or augment hypoalgesia by blocking the habenular α2 receptor after ICS. The recovery of morphine analgesia in the ICS model, on the other hand, seems to be mediated through a blockade of α2 receptor in unidentified brain regions. SIGNIFICANCE STATEMENT: This study reports possible mechanisms underlying the complete reversal of hyperalgesia and recovery of morphine analgesia by mirtazapine, a unique antidepressant with adrenergic α2 and serotonergic receptor antagonist properties, in a type of intermittently repeated stress (ICS)-induced fibromyalgia-like pain model. Habenula, a brain region which is related to the control of emotional pain, was found to play key roles in the antihyperalgesia, whereas other brain regions appeared to be involved in the recovery of morphine analgesia in the ICS model.
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Antagonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Antidepressivos/uso terapêutico , Dor Crônica/tratamento farmacológico , Fibromialgia/tratamento farmacológico , Hiperalgesia/prevenção & controle , Mirtazapina/uso terapêutico , Morfina/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Animais , Antidepressivos/administração & dosagem , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Injeções Intraventriculares , Injeções Espinhais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mirtazapina/administração & dosagem , Morfina/administração & dosagem , Morfina/uso terapêutico , Medição da Dor , Receptores Adrenérgicos alfa 2/genéticaRESUMO
Fibromyalgia (FM), a disease of unknown etiology characterized by chronic generalized pain, is partly recapitulated in an animal model induced by repeated acid saline injections into the gastrocnemius muscle. Here, we attempted to investigate the sex difference in pain hypersensitivity (mechanical allodynia and hypersensitivity to electrical stimulation) in the repeated acid saline-induced FM-like generalized pain (AcGP) model. The first unilateral acid injection into gastrocnemius muscle at day 0/D0 and second injection at D5 (post day 0, P0) induced transient and long-lasting mechanical allodynia, respectively, on both sides of male and female mice. The pretreatment with gonadectomy did not affect the first injection-induced allodynia in both sexes, but gradually reversed the second injection-induced allodynia in male but not female mice. Moreover, the AcGP in male mice was abolished by intracerebroventricular minocycline treatments during D4-P4 or P5-P11, but not by early treatments during D0-D5 in male but not female mice, suggesting that brain microglia are required for AcGP in late-onset and sex-dependent manners. We also found that the intravenous treatments of splenocytes derived from male but not female mice treated with AcGP caused allodynia in naive mice. In addition, the purified CD4+ T cells derived from splenocytes of acid-treated male mice retained the ability to cause allodynia in naive mice. These findings suggest that FM-like AcGP has multiple sexual dimorphic mechanisms.
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Transcriptional and post-translational regulations are important in peripheral nerve injury-induced neuropathic pain, but little is known about the role of post-transcriptional modification. Our objective was to determine the possible effect of adenosine deaminase acting on RNA (ADAR) enzymes, which catalyze post-transcriptional RNA editing, in tactile allodynia, a hallmark of neuropathic pain. Seven days after L5 spinal nerve transection (SNT) in adult mice, we found an increase in ADAR2 expression and a decrease in ADAR3 expression in the injured, but not in the uninjured, dorsal root ganglions (DRGs). These changes were accompanied by elevated levels of editing at the D site of the serotonin (5-hydroxytryptamine) 2C receptor (5-HT2CR), at the I/V site of coatomer protein complex subunit α (COPA), and at the R/G site of AMPA receptor subunit GluA2 in the injured DRG. Compared to Adar2+/+/Gria2R/R littermate controls, Adar2-/-/Gria2R/R mice completely lacked the increased editing of 5-HT2CR, COPA, and GluA2 transcripts in the injured DRG and showed attenuated tactile allodynia after SNT. Furthermore, the antidepressant fluoxetine inhibited neuropathic allodynia after injury and reduced the COPA I/V site editing in the injured DRG. These findings suggest that ADAR2 is a mediator of injury-induced tactile allodynia and thus a potential therapeutic target for the treatment of neuropathic pain.-Uchida, H., Matsumura, S., Okada, S., Suzuki, T., Minami, T., Ito, S. RNA editing enzyme ADAR2 is a mediator of neuropathic pain after peripheral nerve injury.
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Adenosina Desaminase/genética , Neuralgia/metabolismo , Traumatismos dos Nervos Periféricos/genética , Edição de RNA , Proteínas de Ligação a RNA/genética , Receptores de AMPA/metabolismo , Adenosina Desaminase/farmacologia , Animais , Gânglios Espinais/metabolismo , Masculino , Camundongos Transgênicos , Traumatismos dos Nervos Periféricos/metabolismo , Receptores de AMPA/genética , Serotonina/metabolismoRESUMO
Adenosine deaminase acting on RNA (ADAR) enzymes, ADAR1 and ADAR2, mediates adenosine-to-inosine RNA editing, and their mRNA expressions are altered during developmental, physiological, and pathophysiological processes in the nervous system. The present study attempted to investigate the involvement of epigenetic modifying enzymes, such as DNA methyltransferase (DNMT) and histone deacetylase (HDAC), in the regulation of ADAR1 and ADAR2 mRNA expressions in neuronal cells. Using human neuronal SH-SY5Y cells, we found that the DNMT inhibitor 5-aza-2'-deoxycytidine led to an increase in ADAR2, but not ADAR1, mRNA expression in a concentration-dependent and time-dependent manner. However, treatment with HDAC inhibitor trichostatin A elicited an increase in ADAR2 mRNA expression and a decrease in ADAR1 mRNA expression, and these changes were blocked by actinomycin D, a transcription inhibitor. Taken together, these findings suggest that ADAR1 and ADAR2 expressions are subject to different regulations by DNMT and HDAC enzymes in neuronal SH-SY5Y cells.
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Adenosina Desaminase/metabolismo , Metilases de Modificação do DNA/metabolismo , Histona Desacetilases/metabolismo , Neurônios/enzimologia , Proteínas de Ligação a RNA/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Epigênese Genética/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Neurônios/efeitos dos fármacos , RNA Mensageiro/metabolismoRESUMO
Many organs, including salivary glands, lung, and kidney, are formed by epithelial branching during embryonic development. Branching morphogenesis occurs via either local outgrowths or the formation of clefts that subdivide epithelia into buds. This process is promoted by various factors, but the mechanism of branching morphogenesis is not fully understood. Here we have defined melatonin as a potential negative regulator or "brake" of branching morphogenesis, shown that the levels of it and its receptors decline when branching morphogenesis begins, and identified the process that it regulates. Melatonin has various physiological functions, including circadian rhythm regulation, free-radical scavenging, and gonadal development. Furthermore, melatonin is present in saliva and may have an important physiological role in the oral cavity. In this study, we found that the melatonin receptor is highly expressed on the acinar epithelium of the embryonic submandibular gland. We also found that exogenous melatonin reduces salivary gland size and inhibits branching morphogenesis. We suggest that this inhibition does not depend on changes in either proliferation or apoptosis, but rather relates to changes in epithelial cell adhesion and morphology. In summary, we have demonstrated a novel function of melatonin in organ formation during embryonic development.
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Melatonina/metabolismo , Morfogênese , Receptor MT1 de Melatonina/biossíntese , Receptor MT2 de Melatonina/biossíntese , Glândulas Salivares/metabolismo , Animais , Apoptose/genética , Adesão Celular/genética , Forma Celular/genética , Desenvolvimento Embrionário , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Melatonina/genética , Camundongos , Gravidez , Receptor MT1 de Melatonina/genética , Receptor MT2 de Melatonina/genética , Glândulas Salivares/embriologia , Glândulas Salivares/ultraestruturaRESUMO
Treatment of fibromyalgia is an unmet medical need. To develop novel therapies for the treatment of fibromyalgia, we explored pain therapeutic actions of existing pharmaceuticals, which inhibit the somatic symptoms frequently observed in fibromyalgia patients. This study first examined the therapeutic actions of pilocarpine, which inhibits dry-eye and dry-mouth symptoms, using an experimental fibromyalgia-like chronic pain model produced by intermittent cold stress (ICS) in mice. A single intraperitoneal and intracerebroventricular, but not intrathecal, pilocarpine administration attenuated ICS-induced thermal hyperalgesia and mechanical allodynia, and this action was abolished by muscarinic antagonist pirenzepine (i.c.v.). Treatment with 1-10 µg/kg donepezil (i.p.), which can easily penetrate into the brain, also showed similar therapeutic effects. Importantly, we found that both pilocarpine and donepezil produced antihyperalgesic effects via supraspinal action. Furthermore, repeated donepezil treatments completely cured the ICS-induced hyperalgesia and allodynia even after the cessation of drug treatments. Acute and chronic treatments of these cholinomimetics had no effects on the nociceptive threshold in control animals. By contrast, the lack of morphine (i.c.v.) analgesia initially observed in the ICS model remained in ICS model mice treated with long-term donepezil. Collectively, these findings suggest that stimulation of the muscarinic cholinergic system effectively inhibits some mechanisms underlying chronic pain in the ICS model, but does not inhibit the lack of descending pain-inhibitory mechanisms, which are driven by central morphine.
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Dor Crônica/tratamento farmacológico , Dor Crônica/etiologia , Fibromialgia/tratamento farmacológico , Indanos/uso terapêutico , Nootrópicos/uso terapêutico , Piperidinas/uso terapêutico , Estresse Psicológico/complicações , Analgésicos Opioides/uso terapêutico , Animais , Donepezila , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Indanos/administração & dosagem , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Morfina/uso terapêutico , Agonistas Muscarínicos/uso terapêutico , Nootrópicos/administração & dosagem , Medição da Dor/efeitos dos fármacos , Pilocarpina/uso terapêutico , Piperidinas/administração & dosagemRESUMO
Amyloidosis is a protein conformational disorder with the distinctive feature of extracellular accumulation of amyloid fibrils that come from different proteins. In the ligamentum flavum of the lumbar spine, amyloid deposits were frequently found in elderly patients with lumbar spinal canal stenosis and were at least partially formed by wild-type transthyretin. However, how amyloid deposits in the ligamentum flavum affect lumbar spinal canal stenosis has remained unclear. In this study, we analyzed clinical, pathologic, and radiologic findings of patients with lumbar spinal canal stenosis who had amyloid deposits in the ligamentum flavum. We studied 95 ligamentum flavum specimens obtained from 56 patients with lumbar spinal canal stenosis and 21 ligamentum flavum specimens obtained from 19 patients with lumbar disk herniation. We evaluated histopathologic findings and clinicoradiologic manifestations, such as thickness of the ligamentum flavum and lumbar spinal segmental instability. We found that all 95 ligamentum flavum specimens resected from patients with lumbar spinal canal stenosis had amyloid deposits, which we classified into two types, transthyretin-positive and transthyretin-negative, and that transthyretin amyloid formation in the ligamentum flavum of patients with lumbar spinal canal stenosis was an age-associated phenomenon. The amount of amyloid in the ligamentum flavum was related to clinical manifestations of lumbar spinal canal stenosis, such as thickness of the ligamentum flavum and lumbar spinal segmental instability, in the patients with lumbar spinal canal stenosis with transthyretin-positive amyloid deposits. To our knowledge, this report is the first to show clinicopathologic correlations in transthyretin amyloid deposits of the ligamentum flavum. In conclusion, transthyretin amyloid deposits in the ligamentum flavum may be related to the pathogenesis of lumbar spinal canal stenosis in elderly patients.
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Amiloide/efeitos adversos , Ligamento Amarelo/patologia , Pré-Albumina/efeitos adversos , Estenose Espinal/etiologia , Idoso , Amiloide/análise , Feminino , Humanos , Imuno-Histoquímica , Região Lombossacral , Imageamento por Ressonância Magnética , Masculino , Espectrometria de Massas , Pré-Albumina/análise , Estenose Espinal/metabolismo , Estenose Espinal/patologiaRESUMO
Neuropathic pain is characterized by complicated combination of positive (e.g., hyperalgesia and allodynia) and negative (e.g., hypoesthesia and hypoalgesia) symptoms, and is often refractory to conventional pharmacological agents, including morphine. Although the molecular mechanisms for positive symptoms are extensively studied, those for negative symptoms are poorly understood. There is convincing evidence that altered gene expression within peripheral and central nervous systems is a key mechanism for neuropathic pain; however, its transcriptional mechanisms are poorly understood. Epigenetic modifications, such as DNA methylation and histone modifications (e.g., acetylation, methylation, and phosphorylation), are known to cause stable gene expression via chromatin remodeling. These mechanisms have a role not only in the determination of developmental cell fates, but also in the physiological and pathological processes in nervous system. Moreover, epigenetic therapies using epigenetic modifying compounds are progressively advanced in the treatments of diverse diseases, including cancer and neurological diseases. Importantly, there is emerging evidence that a variety of genes undergo epigenetic regulation via DNA methylation and histone modifications within peripheral and central nervous systems, thereby contributing to the alterations in both pain sensitivity and pharmacological efficacy in neuropathic pain. In this review, we will highlight the epigenetic gene regulation underlying neuropathic pain, especially focusing on the negative symptoms. Moreover, we will discuss whether epigenetic mechanisms can serve as a potential target to treat neuropathic pain.
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Epigênese Genética/fisiologia , Neuralgia/genética , Neuralgia/terapia , Limiar da Dor/fisiologia , Animais , Marcação de Genes/tendências , Humanos , Neuralgia/patologia , Neurônios Aferentes/patologia , Neurônios Aferentes/fisiologiaRESUMO
BACKGROUND: Paclitaxel, which is widely used for the treatment of solid tumors, causes neuropathic pain via poorly understood mechanisms. Previously, we have demonstrated that lysophosphatidic acid (LPA) and its receptors (LPA1 and LPA3) are required for the initiation of peripheral nerve injury-induced neuropathic pain. The present study aimed to clarify whether LPA and its receptors could mediate paclitaxel-induced neuropathic pain. RESULTS: Intraperitoneal administration of paclitaxel triggered a marked increase in production of LPA species (18:1-, 16:0-, and 18:0-LPA) in the spinal dorsal horn. Also, we found significant activations of spinal cytosolic phospholipase A2 and calcium-independent phospholipase A2 after the paclitaxel treatment. The paclitaxel-induced LPA production was completely abolished not only by intrathecal pretreatment with neurokinin 1 (NK1) or N-methyl-D-aspartate (NMDA) receptor antagonist, but also in LPA1 receptor-deficient (Lpar1-/-) and LPA3 receptor-deficient (Lpar3-/-) mice. In addition, the pharmacological blockade of NK1 or NMDA receptor prevented a reduction in the paw withdrawal threshold against mechanical stimulation after paclitaxel treatments. Importantly, the paclitaxel-induced mechanical allodynia was absent in Lpar1-/- and Lpar3-/- mice. CONCLUSIONS: These results suggest that LPA1 and LPA3 receptors-mediated amplification of spinal LPA production is required for the development of paclitaxel-induced neuropathic pain.
Assuntos
Antineoplásicos Fitogênicos/toxicidade , Lisofosfolipídeos/metabolismo , Neuralgia , Paclitaxel/toxicidade , Fosfolipases A2/metabolismo , Receptores de Ácidos Lisofosfatídicos/metabolismo , Animais , Modelos Animais de Doenças , Maleato de Dizocilpina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuralgia/induzido quimicamente , Neuralgia/complicações , Neuralgia/patologia , Medição da Dor/efeitos dos fármacos , Fosfolipases A2/genética , Piperidinas/farmacologia , Receptores de Ácidos Lisofosfatídicos/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Corno Dorsal da Medula Espinal/efeitos dos fármacos , Corno Dorsal da Medula Espinal/metabolismo , Fatores de TempoRESUMO
Cleft palate results from a mixture of genetic and environmental factors and occurs when the bilateral palatal shelves fail to fuse. The objective of this study was to search for new genes involved in mouse palate formation. Gene expression of murine embryonic palatal tissue was analyzed at various developmental stages before, during, and after palate fusion using GeneChip® microarrays. Ceacam1 was one of the highly up-regulated genes during palate formation, and this was confirmed by quantitative real-time PCR. Immunohistochemical staining showed that CEACAM1 was present in prefusion palatal epithelium and was degraded during fusion. To investigate the developmental role of CEACAM1, function-blocking antibody was added to embryonic mouse palate in organ culture. Palatal fusion was inhibited by this function-blocking antibody. To investigate the subsequent developmental role of CEACAM1, we characterized Ceacam1-deficient (Ceacam1(-/-)) mice. Epithelial cells persisted abnormally at the midline of the embryonic palate even on day E16.0, and palatal fusion was delayed in Ceacam1(-/-) mice. TGFß3 expression, apoptosis, and cell proliferation in palatal epithelium were not affected in the palate of Ceacam1(-/-)mice. However, CEACAM1 expression was retained in the remaining MEE of TGFß-deficient mice. These results suggest that CEACAM1 has roles in the initiation of palatal fusion via epithelial cell adhesion.
Assuntos
Antígenos CD/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Epiteliais/metabolismo , Palato/embriologia , Palato/metabolismo , Animais , Antígenos CD/genética , Apoptose , Moléculas de Adesão Celular/genética , Morte Celular , Proliferação de Células , Embrião de Mamíferos/metabolismo , Células Epiteliais/citologia , Face/embriologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Integrases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microdissecção , Análise de Sequência com Séries de Oligonucleotídeos , Técnicas de Cultura de Órgãos , Organogênese/genética , Palato/citologia , Proteínas Serina-Treonina Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Reprodutibilidade dos Testes , Transdução de Sinais , Crânio/citologia , Crânio/embriologia , Crânio/metabolismo , Fator de Crescimento Transformador beta3/metabolismoRESUMO
BACKGROUND: Fibromyalgia (FM) is characterized by chronic widespread pain, which is often refractory to conventional painkillers. Numerous clinical studies have demonstrated that antidepressants are effective in treating FM pain. We previously established a mouse model of FM-like pain, induced by intermittent cold stress (ICS). RESULTS: In this study, we find that ICS exposure causes a transient increase in plasma corticosterone concentration, but not in anxiety or depression-like behaviors. A single intrathecal injection of an antidepressant, such as milnacipran, amitriptyline, mianserin or paroxetine, had an acute analgesic effect on ICS-induced thermal hyperalgesia at post-stress day 1 in a dose-dependent manner. In addition, repeated daily antidepressant treatments during post-stress days 1-5 gradually reversed the reduction in thermal pain threshold, and this recovery was maintained for at least 7 days after the final treatment. In addition, relief from mechanical allodynia, induced by ICS exposure, was also observed at day 9 after the cessation of antidepressant treatment. In contrast, the intravenous administration of these antidepressants at conventional doses failed to provide relief. CONCLUSIONS: These results suggest that the repetitive intrathecal administration of antidepressants permanently cures ICS-induced FM pain in mice.