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1.
Neurochem Res ; 49(4): 1049-1060, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38252396

RESUMO

Chemotherapy-induced peripheral neuropathy (CIPN) is a major challenge for cancer patients who undergo chemotherapy with paclitaxel. Therefore, finding effective therapies for CIPN is crucial. Glatiramer acetate is used to treat multiple sclerosis that exerts neuroprotective properties in various studies. We hypothesized that glatiramer acetate could also improve the paclitaxel-induced peripheral neuropathy. We used a rat model of paclitaxel (2 mg/kg/every other day for 7 doses)-induced peripheral neuropathy. Rats were treated with either different doses of glatiramer acetate (1, 2, 4 mg/kg/day) or its vehicle for 14 days in separate groups. The mechanical and thermal sensitivity of the rats by using the Von Frey test and the Hot Plate test, respectively, were assessed during the study. The levels of oxidative stress (malondialdehyde and superoxide dismutase), inflammatory markers (TNF-α, IL-10, NF-kB), and nerve damage (H&E and S100B staining) in the sciatic nerves of the rats were also measured at the end of study. Glatiramer acetate (2 and 4 mg/kg) exerted beneficial effects on thermal and mechanical allodynia tests. It also modulated the inflammatory response by reducing TNF-α and NF-κB levels, enhancing IL-10 production, and improving the oxidative stress status by lowering malondialdehyde and increasing superoxide dismutase activity in the sciatic nerve of the rats. Furthermore, glatiramer acetate enhanced nerve conduction velocity in all treatment groups. Histological analysis revealed that glatiramer acetate (2 and 4 mg/kg) prevented paclitaxel-induced damage to the nerve structure. These results suggest that glatiramer acetate can alleviate the peripheral neuropathy induced by paclitaxel.


Assuntos
Paclitaxel , Doenças do Sistema Nervoso Periférico , Humanos , Ratos , Animais , Paclitaxel/toxicidade , Acetato de Glatiramer/uso terapêutico , Acetato de Glatiramer/farmacologia , Interleucina-10 , Citocinas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/prevenção & controle , Estresse Oxidativo , Hiperalgesia/induzido quimicamente , Superóxido Dismutase/metabolismo , Malondialdeído/farmacologia
2.
Langmuir ; 40(39): 20559-20575, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39276104

RESUMO

The growing interest in large-scale underground hydrogen (H2) storage (UHS) emphasizes the need for a comprehensive understanding of the fundamental characteristics of subsurface environments. The wetting preference of subsurface rock is a crucial parameter influencing the H2 flow behavior during storage and withdrawal processes. In this study, we utilized molecular dynamics simulation to evaluate the wetting preference of the silica surface in subsurface hydrogen systems, with the aim of addressing disparities observed in experimental results. We conducted an initial comprehensive assessment of potential models, comparing the wettability of five common silica surfaces with different surface morphologies and hydroxyl densities in CO2-H2/water/silica systems against experimental data. After introducing the INTERFACE force field as the most accurate potential model for the silica surface, we evaluated the wetting behavior of the α-quartz (101) surface with a hydroxyl density of 5.9 number/nm2 under the impact of actual geological storage conditions (333-413 K and 10-30 MPa), the coexistence of cushion gases (i.e., CO2, CH4, and N2) at various mole fractions, and pH levels ranging from 2 to 11 characterized through considering the negative charges of 0 to -0.12 C/m2 via deprotonation of silanol on the silica surface. Our results indicate that neither pressure nor temperature has a significant impact on the wetness of the silica in the case of pure H2 (single component UHS operations). However, when CO2 coexists with H2, especially at higher mole fractions, an increase in pressure and a decrease in temperature lead to higher contact angles. Moreover, when the mole fraction of cushion gas ranges from 0 to 1, the contact angle increases 20, 9.5, and 4.5° for CO2, CH4, and N2, respectively, on the neutral silica substrate. Interestingly, at higher pH conditions where the silica surface carries a negative charge, the contact angle considerably reduces where surface charges of -0.03 and -0.06 C/m2 result in an average reduction of 20 and 80% in the contact angle, respectively. More importantly, at a pH of ∼11 (-0.12 C/m2), a 0° contact angle is observed for the silica surface under all temperatures, pressures, types of cushion gases, and varying mole fractions.

3.
Langmuir ; 39(36): 12680-12691, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37650690

RESUMO

Hydrogen (H2) underground storage has attracted considerable attention as a potentially efficient strategy for the large-scale storage of H2. Nevertheless, successful execution and long-term storage and withdrawal of H2 necessitate a thorough understanding of the physical and chemical properties of H2 in contact with the resident fluids. As capillary forces control H2 migration and trapping in a subsurface environment, quantifying the interfacial tension (IFT) between H2 and the resident fluids in the subsurface is important. In this study, molecular dynamics (MD) simulation was employed to develop a data set for the IFT of H2-brine systems under a wide range of thermodynamic conditions (298-373 K temperatures and 1-30 MPa pressures) and NaCl salinities (0-5.02 mol·kg-1). For the first time to our knowledge, a comprehensive assessment was carried out to introduce the most accurate force field combination for H2-brine systems in predicting interfacial properties with an absolute relative deviation (ARD) of less than 3% compared with the experimental data. In addition, the effect of the cation type was investigated for brines containing NaCl, KCl, CaCl2, and MgCl2. Our results show that H2-brine IFT decreases with increasing temperature under any pressure condition, while higher NaCl salinity increases the IFT. A slight decrease in IFT occurs when the pressure increases. Under the impact of cation type, Ca2+ can increase IFT values more than others, i.e., up to 12% with respect to KCl. In the last step, the predicted IFT data set was used to provide a reliable correlation using machine learning (ML). Three white-box ML approaches of the group method of data handling (GMDH), gene expression programming (GEP), and genetic programming (GP) were applied. GP demonstrates the most accurate correlation with a coefficient of determination (R2) and absolute average relative deviation (AARD) of 0.9783 and 0.9767%, respectively.

4.
Rev Med Virol ; 32(3): e2289, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34499784

RESUMO

Since the Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), our understanding regarding the pathophysiology and clinical manifestations of this disease have been improving. However, we still have limited data on long-term effects and lingering symptoms of post COVID-19 recovery. Despite predilection of COVID-19 for lungs, multiple extra-pulmonary manifestations appear in multiple organs and biological systems and with continued infection and recovery worldwide. It is necessary that clinicians provide patients with previous SARS-CoV-2 infection with expectations of long-term effects during or after recovery from COVID-19. Herein, we review the long-term impact of COVID-19 on different organ systems reported from different clinical studies. Understanding risk factors and signs and symptoms of long-term consequences after recovery from COVID-19 will allow for proper follow-up and management of the disease post recovery.


Assuntos
COVID-19 , Humanos , Pulmão , Pandemias , SARS-CoV-2
5.
Mol Biol Rep ; 50(12): 10409-10425, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37848760

RESUMO

Tryptophan metabolism along the kynurenine pathway is of central importance for the immune function. It prevents hyperinflammation and induces long-term immune tolerance. Accumulating evidence also demonstrates cytoprotective and immunomodulatory properties of kynurenine pathway in conditions affecting either central or peripheral nervous system as well as other conditions such as inflammatory bowel disease (IBD). Although multilevel association exists between the inflammatory bowel disease (IBD) and various neurologic (e.g., neurodegenerative) disorders, it is believed that the kynurenine pathway plays a pivotal role in the development of both IBD and neurodegenerative disorders. In this setting, there is strong evidence linking the gut-brain axis with intestinal dysfunctions including IBD which is consistent with the fact that the risk of neurodegenerative diseases is higher in IBD patients. This review aims to highlight the role of kynurenine metabolic pathway in various neurologic and psychiatric diseases as well as relationship between IBD and neurodegenerative disorders in the light of the kynurenine metabolic pathway.


Assuntos
Doenças Inflamatórias Intestinais , Transtornos Mentais , Doenças Neurodegenerativas , Humanos , Cinurenina/metabolismo , Redes e Vias Metabólicas
6.
Pain Med ; 24(4): 369-381, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36255268

RESUMO

OBJECTIVE: Approximately one in four total knee replacement patients develop persistent pain. Identification of those at higher risk could help inform optimal management. METHODS: We searched MEDLINE, EMBASE, CINAHL, AMED, SPORTDiscus, and PsycINFO for observational studies that explored the association between risk factors and persistent pain (≥3 months) after total knee replacement. We pooled estimates of association for all independent variables reported by >1 study. RESULTS: Thirty studies (26,517 patients) reported the association of 151 independent variables with persistent pain after knee replacement. High certainty evidence demonstrated an increased risk of persistent pain with pain catastrophizing (absolute risk increase [ARI] 23%, 95% confidence interval [CI] 12 to 35), younger age (ARI for every 10-year decrement from age 80, 4%, 95% CI 2 to 6), and moderate-to-severe acute post-operative pain (ARI 30%, 95% CI 20 to 39). Moderate certainty evidence suggested an association with female sex (ARI 7%, 95% CI 3 to 11) and higher pre-operative pain (ARI 35%, 95% CI 7 to 58). Studies did not adjust for both peri-operative pain severity and pain catastrophizing, which are unlikely to be independent. High to moderate certainty evidence demonstrated no association with pre-operative range of motion, body mass index, bilateral or unilateral knee replacement, and American Society of Anesthesiologists score. CONCLUSIONS: Rigorously conducted observational studies are required to establish the relative importance of higher levels of peri-operative pain and pain catastrophizing with persistent pain after knee replacement surgery.


Assuntos
Artroplastia do Joelho , Procedimentos Ortopédicos , Humanos , Feminino , Idoso de 80 Anos ou mais , Artroplastia do Joelho/efeitos adversos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia , Fatores de Risco
7.
Toxicol Appl Pharmacol ; 454: 116254, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36155770

RESUMO

BACKGROUND: Early post-stroke seizure frequently occurs in stroke survivors within the first few days and is associated with poor functional outcomes. Therefore, efficient treatments of such complications with less adverse effects are pivotal. In this study, we investigated the possible beneficial effects of lasmiditan and sumatriptan against post-stroke seizures in mice and explored underlying mechanisms in their effects. METHODS: Stroke was induced by double ligation of the right common carotid artery in mice. Immediately after the ligation, lasmiditan (0.1 mg/kg, intraperitoneally [i.p.]) or sumatriptan (0.03 mg/kg, i.p.) were administered. Twenty-four hours after the stroke induction, seizure susceptibility was evaluated using the pentylenetetrazole (PTZ)-induced clonic seizure model. In separate experiments, naltrexone (a non-specific opioid receptor antagonist) and glibenclamide (a KATP channel blocker) were administered 15 min before lasmiditan or sumatriptan injection. To evaluate the underlying signaling pathways, ELISA analysis of inflammatory cytokines (TNF-α and IL-1ß) and western blot analysis of anti- and pro-apoptotic markers (Bcl-2 and Bax) were performed on mice isolated brain tissues. RESULTS: Lasmiditan (0.1 mg/kg, i.p.) and sumatriptan (0.03 mg/kg, i.p.) remarkably decreased seizure susceptibility in stroke animals by reducing inflammatory cytokines and neuronal apoptosis. Concurrent administration of naltrexone (10 mg/kg, i.p.) or glibenclamide (0.3 mg/kg, i.p.) with lasmiditan or sumatriptan resulted in a higher neuroprotection against clonic seizures and efficiently reduced the inflammatory and apoptotic markers. CONCLUSION: Lasmiditan and sumatriptan significantly increased post-stroke seizure thresholds in mice by suppressing inflammatory cytokines and neuronal apoptosis. Lasmiditan and sumatriptan seem to exert higher effects on seizure threshold with concurrent administration of the opioid receptors or KATP channels modulators.


Assuntos
Fármacos Neuroprotetores , Acidente Vascular Cerebral , Trifosfato de Adenosina , Animais , Anticonvulsivantes/farmacologia , Benzamidas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glibureto/farmacologia , Glibureto/uso terapêutico , Camundongos , Modelos Teóricos , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Pentilenotetrazol , Piperidinas , Bloqueadores dos Canais de Potássio , Canais de Potássio/metabolismo , Piridinas , Receptores Opioides , Convulsões/tratamento farmacológico , Convulsões/etiologia , Convulsões/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Sumatriptana , Fator de Necrose Tumoral alfa , Proteína X Associada a bcl-2
8.
Epilepsy Behav ; 130: 108649, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344809

RESUMO

BACKGROUND: Status epilepticus (SE) is a continuous episode of seizures which leads to hippocampal neurodegeneration, severe systemic inflammation, and extreme damage to the brain. Modafinil, a psychostimulant and wake-promoting agent, has exerted neuroprotective and anti-inflammatory effects in previous preclinical studies. The aim of this study was to assess effects of modafinil on the lithium-pilocarpine-induced SE rat model and to explore possible involvement of tumor necrosis factor-α (TNF-α) and nitric oxide (NO) pathways in this regard. METHODS: Status epilepticus was provoked by injection of lithium chloride (127 mg/kg, intraperitoneally [i.p]) and pilocarpine (60 mg/kg, i.p.) in rats. Animals received different modafinil doses (50, 75, 100, and 150 mg/kg, i.p.) and SE scores were documented over 3 hours of duration. Moreover, the role of the nitrergic pathway in the effects of modafinil was evaluated by injection of the non-selective NO synthase (NOS) inhibitor L-NG-Nitro arginine methyl ester (L-NAME, 10 mg/kg, i.p.), the selective neuronal NOS inhibitor 7-nitroindazole (30 mg/kg, i.p.), and the selective inducible NOS inhibitor aminoguanidine (100 mg/kg, i.p.) 15 min before saline/vehicle or modafinil. The ELISA method was used to quantify TNF-α and NO metabolite levels in the isolated hippocampus. RESULTS: Modafinil at 100 mg/kg significantly decreased SE scores (P < 0.01). Pre-treatment with L-NAME, 7-nitroindazole, and aminoguanidine significantly reversed the anticonvulsive effects of modafinil. Status epilepticus-induced animals showed significantly higher NO metabolite and TNF-α levels in their hippocampal tissues, an effect that was reversed by modafinil (100 mg/kg, i.p.) treatment. Administration of NOS inhibitors resulted in excessive NO level reduction but an escalation of TNF-α level in modafinil-treated SE-animals. CONCLUSION: Our study revealed anticonvulsive effects of modafinil in the lithium-pilocarpine-induced SE rat model via possible involvement of TNF-α and nitrergic pathways.


Assuntos
Pilocarpina , Estado Epiléptico , Animais , Humanos , Lítio/efeitos adversos , Modafinila/efeitos adversos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Pilocarpina/farmacologia , Ratos , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/patologia , Fator de Necrose Tumoral alfa
9.
J Cardiothorac Vasc Anesth ; 36(1): 178-183, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332843

RESUMO

OBJECTIVES: Speckle-tracking echocardiography is a promising tool for evaluating cardiac diastolic dysfunction. A correlation between left atrial strain rate during atrial contraction and the severity of diastolic dysfunction previously has been demonstrated. Because visualization of the left atrial walls is difficult with transesophageal echocardiography, the authors evaluated the use of left ventricular strain rate during atrial contraction as a substitute for left atrial strain rate to intraoperatively measure the extent of cardiac diastolic dysfunction. DESIGN: Retrospective clinical study. SETTING: Single institutional study. PARTICIPANTS: Sixty-six patients who underwent cardiac surgery between January 2018 and January 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Preoperative echocardiographic reports and intraoperative echocardiographic images of the participants were studied. The correlation of cardiac diastolic dysfunction stage with the peak longitudinal strain rate during late diastole and the time to peak value were evaluated. The late diastolic peak longitudinal strain rate was correlated significantly with the stage of diastolic dysfunction (r = -0.64, p < 0.0001). There was no significant correlation between the stage of diastolic dysfunction and the time to peak value (r = -0.17, p = 0.18). A late diastolic peak longitudinal strain rate <0.68 1/s had a sensitivity of 80% and specificity of 81% for predicting grade 2 or 3 diastolic dysfunction. CONCLUSIONS: The late diastolic peak longitudinal strain rate correlates with the severity of diastolic dysfunction in patients undergoing cardiac surgery.


Assuntos
Ecocardiografia Transesofagiana , Disfunção Ventricular Esquerda , Diástole , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda
10.
Mater Chem Phys ; 276: 125382, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34725529

RESUMO

The recent pandemic of COVID-19 has raised global health concerns. Preventing severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) activity in the body is a very promising method to overcome the COVID-19 pandemic. One of the prevention methods is constraining the binding process among the human cell receptor-ACE2 and coronavirus spike protein. In the research done, the effect of deformation of the spike protein structure, due to the covalent organic frameworks (COFs), in reducing the interactions of ACE2 and the spike protein by the computational method was investigated. In this regard, atomic analysis of the interactions of ACE2 and the spike protein is provided using a molecular dynamics simulation. First, we investigated the interactions of the three different COFs, including COF-78, DAAQ-TFP, and COF-OEt, with the spike protein by analyzing the bond energies, as well as structural changes of the spike protein. Then, intermolecular interactions of the deformed spike protein along with ACE2 were assessed to clarify the protein's fusion after the deformation. As indicated by the results, although all introduced COFs deformed the spike protein in an effective way, COF-78 showed the best performance in the prevention of spike protein-ACE2 interactions by changing the molecular structure of the protein. Indeed, the interaction analysis of the deformed spike protein by COF-78 with the ACE2 showed that their interactions had the lowest absolute value of energy, along with the least amount of hydrogen bonds, in which the compaction of the protein was lower compared to the other deformed proteins. Moreover, having a high contact area with an aqueous media as well as severe fluctuations during the simulation time confirmed the positive performance of COF-78. In the current study, we aimed to introduce novel materials and COVID-19 prevention methodology that can be used in face masks and for surface disinfection.

11.
Drug Dev Res ; 82(7): 896-906, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33792938

RESUMO

Sumatriptan is the first available medication from triptans family that was approved by the U.S. Food and Drug Administration for migraine attacks and cluster headaches in 1991. Most of its action is mediated by selective 5-HT1B/1D receptor agonism. Recent investigations raised the possibility of repositioning of this drug to other indications beyond migraine, as increasing evidence suggests for an anti-inflammatory property of sumatriptan. We performed a literature search using PubMed, Web of Science, Scopus, and Google Scholar using "inflammation AND sumatriptan" or "inflammation AND 5HT1B/D" as the keywords. Then, articles were screened for their relevance and those directly discussing the correlation between inflammation and sumatriptan or 5HT1B/D were included. Total references reviewed or inclusion/exclusion were 340 retrieved full-text articles (n = 340), then based on critical assessment 66 of them were included in this systematic review. Our literature review indicates that at low doses, sumatriptan can reduce inflammatory markers (e.g., interleukin-1ß, tumor necrosis factor-α, and nuclear factor-κB), affects caspases and changes cells lifespan. Additionally, nitric oxide synthase and nitric oxide signaling seem to be regulated by this drug. It also inhibits the release of calcitonin gene-related peptide. Sumatriptan protects against many inflammatory conditions including cardiac and mesenteric ischemia/reperfusion, skin flap, pruritus, peripheral, and central nervous system injuries such as spinal cord injury, testicular torsion-detorsion, oral mucositis, and other experimental models. Considering the safety and potency of low dose sumatriptan compared to corticosteroids and other immunosuppressive medications, it is worth to take advantage of sumatriptan in inflammatory conditions.


Assuntos
Transtornos de Enxaqueca , Sumatriptana , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Transtornos de Enxaqueca/tratamento farmacológico , Sumatriptana/farmacologia , Sumatriptana/uso terapêutico , Fator de Necrose Tumoral alfa , Estados Unidos
12.
J Stroke Cerebrovasc Dis ; 29(5): 104700, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32093987

RESUMO

BACKGROUND: It has been proposed that the presence of a multiple territory stroke pattern (MTSP) on brain imaging may aid identification of patients with covert atrial fibrillation (AF). However, it is uncertain whether this association holds true among patients treated with intravenous recombinant tissue plasminogen activator (rtPA) because clot fragmentation may affect MTSP prevalence. METHODS/DESIGN: Retrospective analysis of 149 acute ischemic stroke patients treated with intravenous rtPA who underwent brain MRI. Presence of multiple acute infarctions on brain MRI that involved more than one vascular territory was considered to denote MTSP. Stroke etiology was categorized as nonembolic, cardioembolic (CES), and embolic stroke of undetermined source (ESUS). RESULTS: In the entire cohort, subjects with CES and ESUS had significantly more often an MTSP than subjects with other determined stroke mechanism (P= .007). Although numerically relatively more patients had an MTSP as compared to a non-MTSP among subjects with CES (52% versus 33.9%) and ESUS (44% versus 34.7%), this difference did not reach significance after Bonferroni-adjustment for multiple comparisons (P> .05, each). There was no difference in the prevalence of an MTSP among subjects with known (n = 11/51; 21.6%) versus subsequently diagnosed (n = 1/3; 33.3%) AF (P= .54). CONCLUSIONS: Our findings indicate that the known association of multiterritory infarct with AF and ESUS is maintained after thrombolysis. In light of its high specificity, MTSP represents a good marker for AF-related stroke etiology; nevertheless, overall sensitivity for AF was low highlighting that an absent MTSP does not rule out AF.


Assuntos
Fibrilação Atrial/epidemiologia , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/epidemiologia , Imagem de Difusão por Ressonância Magnética , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Infusões Intravenosas , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Proteínas Recombinantes/administração & dosagem , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do Tratamento
13.
Epilepsy Behav ; 87: 25-31, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30170259

RESUMO

BACKGROUND: Stressful conditions affect the brain's neurotransmission and neural pathways that are involved in seizure susceptibility. Stress alters the intensity and/or frequency of seizures. Although evidence indicates that chronic stress exerts proconvulsant effects and acute stress has anticonvulsant properties, the underlying mechanisms which mediate these effects are not well understood. In the present study, we assessed the role of endogenous opioids, endocannabinoids, as well as functional interaction between opioid and cannabinoid systems in the anticonvulsant effects of acute foot-shock stress (FSS) against pentylenetetrazole (PTZ)-induced seizures in mice. METHODS: Prolonged intermittent FSS was chosen as an acute stress model. Seizure threshold was determined after 30 min of stress induction in male Naval Medical Research Institute (NMRI) mice (20-30 g). Opioid and cannabinoid receptor antagonists were administered before animal placement in the FSS apparatus. RESULTS: Acute FSS significantly decreased seizure susceptibility in animals. The administration of the cannabinoid receptor 1 (CB1) antagonist, AM251, completely blocked the anticonvulsant effect of acute FSS at the doses of 1 pg/kg-100 µg/kg but not at 1 fg/kg. Pretreatment with the nonspecific opioid receptor antagonist, naltrexone (NTX), significantly inhibited the anticonvulsant effects of acute FSS at 1 and 2 mg/kg but not at 0.3 mg/kg. However, coadministration of the subeffective doses of AM251 (1 fg/kg) and NTX (0.3 mg/kg) reversed the anticonvulsant effects of acute FSS. CONCLUSIONS: Opioid and cannabinoid systems are involved in the anticonvulsant effects of acute FSS, and these neurotransmission systems interact functionally in response to acute FSS.


Assuntos
Antagonistas de Receptores de Canabinoides/farmacologia , Convulsivantes/farmacologia , Eletrochoque , Antagonistas de Entorpecentes/farmacologia , Pentilenotetrazol/farmacologia , Convulsões/induzido quimicamente , Convulsões/prevenção & controle , Estresse Psicológico , Analgésicos Opioides , Animais , Antagonistas de Receptores de Canabinoides/administração & dosagem , Modelos Animais de Doenças , Masculino , Camundongos , Naltrexona/farmacologia , Antagonistas de Entorpecentes/administração & dosagem , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptores de Canabinoides
14.
Epilepsy Behav ; 62: 291-6, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27521722

RESUMO

Zolpidem is a hypnotic medication that mainly exerts its function through activating γ-aminobutyric acid (GABA)A receptors. There is some evidence that zolpidem may have anticonvulsive effects. However, the mechanisms underlying this effect have not been elucidated yet. In the present study, we used the pentylentetrazole (PTZ)-induced generalized seizure model in mice to investigate whether zolpidem can affect seizure threshold. We also further evaluated the roles of ATP-sensitive potassium (KATP) channels as well as µ-opioid receptors in the effects of zolpidem on seizure threshold. Our data showed that zolpidem in a dose-dependent manner increased the PTZ-induced seizure threshold. The noneffective (i.e., did not significantly alter the PTZ-induced seizure threshold by itself) doses of KATP channel blocker (glibenclamide) and nonselective opioid receptor antagonist (naloxone) were able to inhibit the anticonvulsive effect of zolpidem. Additionally, noneffective doses of either KATP channel opener (cromakalim) or nonselective µ-opioid receptor agonist (morphine) in combination with a noneffective dose of zolpidem exerted a significant anticonvulsive effect on PTZ-induced seizures in mice. A combination of noneffective doses of naloxone and glibenclamide, which separately did not affect zolpidem effect on seizure threshold, inhibited the anticonvulsive effects of zolpidem. These results suggest a role for KATP channels and the opioid system, alone or in combination, in the anticonvulsive effects of zolpidem.


Assuntos
Anticonvulsivantes/uso terapêutico , Canais KATP/metabolismo , Piridinas/uso terapêutico , Convulsões/tratamento farmacológico , Analgésicos Opioides/uso terapêutico , Animais , Cromakalim/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Masculino , Camundongos , Morfina/uso terapêutico , Pentilenotetrazol/efeitos adversos , Convulsões/metabolismo , Zolpidem , Ácido gama-Aminobutírico/uso terapêutico
15.
Mol Cell Proteomics ; 13(1): 63-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24105792

RESUMO

Nitric oxide (NO) mediates a substantial part of its physiologic functions via S-nitrosylation, however the cellular substrates for NO-mediated S-nitrosylation are largely unknown. Here we describe the S-nitrosoproteome using a high-density protein microarray chip containing 16,368 unique human proteins. We identified 834 potentially S-nitrosylated human proteins. Using a unique and highly specific labeling and affinity capture of S-nitrosylated proteins, 138 cysteine residues on 131 peptides in 95 proteins were determined, defining critical sites of NO's actions. Of these cysteine residues 113 are novel sites of S-nitrosylation. A consensus sequence motif from these 834 proteins for S-nitrosylation was identified, suggesting that the residues flanking the S-nitrosylated cysteine are likely to be the critical determinant of whether the cysteine is S-nitrosylated. We identify eight ubiquitin E3 ligases, RNF10, RNF11, RNF41, RNF141, RNF181, RNF208, WWP2, and UBE3A, whose activities are modulated by S-nitrosylation, providing a unique regulatory mechanism of the ubiquitin proteasome system. These results define a new and extensive set of proteins that are susceptible to NO regulation via S-nitrosylation. Similar approaches could be used to identify other post-translational modification proteomes.


Assuntos
Óxido Nítrico/metabolismo , Análise Serial de Proteínas , Processamento de Proteína Pós-Traducional/genética , Proteoma , Humanos , Proteínas/metabolismo
16.
Dig Dis Sci ; 59(11): 2675-81, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24898099

RESUMO

BACKGROUND: Cirrhosis, associated with a host of hemodynamic abnormalities, could affect the gastrointestinal (GI) tract motility. On the other hand, the nonadrenergic noncholinergic (NANC) neurotransmission has been shown to play a pivotal role in GI tract motility and has been linked with release of nitric oxide (NO) on electrical stimulation. In this study, we investigated the effect of biliary cirrhosis on the neurogenic relaxation of rat gastric fundus and anococcygeus muscle and also the possible role of nitric oxide system in this manner. METHODS: Isolated gastric fundus and anococcygeus strips of sham-operated and biliary cirrhotic (4 weeks after bile duct ligation) rats were mounted under tension in a standard organ bath. Electrical stimulation was applied to obtain NANC-mediated relaxations in precontracted gastric fundus and anococcygeus muscle. The neurogenic relaxations were examined in the presence of different doses of NO synthase inhibitor, N (w)-Nitro-L-Arginine Methyl Ester (L-NAME). The concentration-dependent relaxant responses to the NO donor sodium nitroprusside were also evaluated. RESULTS: The neurogenic relaxation of both gastric fundus and anococcygeus muscle was significantly (P < 0.001) increased in cirrhotic animals. L-NAME (0.03-1,000 µM) inhibited relaxations in both groups in a dose-dependent manner (P < 0.001), but cirrhotic groups were more resistant to the inhibitory effects of L-NAME (P < 0.01). Sodium nitroprusside-mediated relaxations were similar in two groups. CONCLUSIONS: This study for the first time demonstrated that cirrhosis increases the NO-mediated neurogenic relaxation of both rat gastric fundus and anococcygeus muscle, suggesting a crucial role for the neurogenic NO in the pathophysiology of disturbed GI motility in cirrhosis.


Assuntos
Relaxamento Muscular/fisiologia , Estômago/inervação , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Cirrose Hepática Biliar , Masculino , Relaxamento Muscular/efeitos dos fármacos , Músculo Esquelético , NG-Nitroarginina Metil Éster/administração & dosagem , NG-Nitroarginina Metil Éster/farmacologia , Nitroprussiato/administração & dosagem , Nitroprussiato/farmacologia , Ratos , Ratos Sprague-Dawley , Estômago/fisiologia
17.
Cureus ; 16(2): e53705, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38455772

RESUMO

Here we report a rare case with concurrent longitudinal extensive transverse myelitis (LETM) and leptomeningitis due to West Nile virus infection. A 47-year-old man initially presented with a six-day progressive, intermittent low-grade fever, headache, diplopia, malaise, myalgia, lower back pain, and difficulty walking that developed into progressive asymmetric paralysis. Initial lab work was notable for mild lactic acidosis and hyperCKemia. Brain MRI with contrast demonstrated small foci of leptomeningeal enhancement in the cerebellum, pons, medulla, and right CN VI at the cisternal segment. MRI of the spine was remarkable for edema in the spinal cord extending from T10 to L1 with diffuse enlargement of the cord contour at T11 to L1 and subtle enhancement of nerve roots within the thecal sac and cauda equina regions. The patient responded partially to five-day intravenous immunoglobulin therapy (total dose, 2 g/kg). Electromyography four months after the onset of symptoms also showed chronic reinnervation with active denervating features in thoracolumbar myotomes. Clinically, this case highlights the ill-defined and non-specific nature of the presentation of West Nile neuroinvasive disease. It can pose a diagnostic challenge for clinicians and, if unrecognized, is associated with significant morbidity and mortality in older and compromised individuals.

18.
J Epilepsy Res ; 14(1): 9-16, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38978533

RESUMO

Background and Purpose: Sumatriptan protects the brain from damage and enhance the anti-seizure effect of morphine. There is evidence that nitric oxide (NO) may mediate these effects of both drugs. In the present study, we investigated the effects of sumatriptan (0.1-20 mg/kg, intraperitoneal [i.p.]) and morphine (0.1-20 mg/kg, i.p.) alone or in combination on seizure thresholds in an in vivo model of seizure in mice. Using various NO synthase inhibitors as well as the NO precursor, we assessed possible involvement of NO signaling in these effects. Methods: Clonic seizures were induced in male Naval Medical Research Institute mice by intravenous administration of pentylenetetrazol (PTZ). Results: Acute sumatriptan administration exerted anti-convulsive effects at 0.5 (p<0.01) and 1 mg/kg (p<0.05), but pro-convulsive effects at 20 mg/kg (p<0.05). Morphine had anti-convulsive effects at 0.5 (p<0.05) and 1 mg/kg (p<0.001), but exerted pro-convulsive effect at 20 mg/kg (p<0.05). Combination treatment with sub-effective doses of sumatriptan (0.1 mg/kg) and morphine (0.1 mg/kg) significantly (p<0.05) exerted an anti-convulsive effect. Co-administration of the NO precursor L-arginine (60 mg/kg) with sub-effective doses of sumatriptan and morphine significantly (p<0.05) increased seizure threshold compared with sumatriptan alone, but not sumatriptan+morphine group. While concomitant administration of either the non-selective NO synthase (NOS) inhibitor L-NG-nitroarginine methyl ester (5 mg/kg) or the selective inducible NOS inhibitor aminoguanidine (50 mg/kg) with combined sub-effective doses of morphine and sumatriptan produced significant anticonvulsive effects, concomitant administration with the selective neuronal NOS inhibitor 7-nitroindazole (30 mg/kg) inhibited this effect. Conclusions: Our data suggest a possible role for the NO signaling in the anticonvulsive effects of combined sumatriptan and morphine on the PTZ-induced clonic seizures in mice.

19.
Curr Pharm Biotechnol ; 25(13): 1632-1650, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38258770

RESUMO

BACKGROUND: Visceral hypersensitivity (VH) is an overreaction of the gastrointestinal (GI) tract to various stimuli and is characterized by hyperalgesia and/or allodynia. VH contributes to the etiology of many GI dysfunctions, particularly irritable bowel syndrome (IBS). Although the exact mechanisms underlying VH are yet to be found, inflammation and oxidative stress, psychosocial factors, and sensorimotor alterations may play significant roles in it. OBJECTIVE: In this review, we provide an overview of VH and its pathophysiological function in GI disorders. Adverse effects of synthetic drugs may make herbal agents a good candidate for pain management. Therefore, in this review, we will discuss the efficacy of herbal agents in the management of VH with a focus on their anti-inflammatory and antioxidant potentials. METHODS: Data were extracted from clinical and animal studies published in English between 2004 and June, 2020, which were collected from PubMed, Google Scholar, Scopus, and Cochrane Library. RESULTS: Overall, Radix, Melissia, Glycyrrhizae, Mentha, and Liquorice were the most efficient herbals for VH management in IBS and dyspepsia, predominantly through modulation of the mRNA expression of transient receptor potential vanilloid type-1 (TRPV1) and suppression of 5- hydroxytryptamine 3 (5-HT3) or the serotonin receptors. CONCLUSION: Considering the positive effects of herbal formulations in VH management, further research on novel herbal and/or herbal/chemical preparations is warranted.


Assuntos
Gastroenteropatias , Humanos , Animais , Gastroenteropatias/tratamento farmacológico , Preparações de Plantas/uso terapêutico , Preparações de Plantas/farmacologia , Síndrome do Intestino Irritável/tratamento farmacológico , Hiperalgesia/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/farmacologia , Dor Visceral/tratamento farmacológico , Canais de Cátion TRPV/metabolismo
20.
Neurol Res ; 46(9): 859-867, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38825034

RESUMO

OBJECTIVES: Amyotrophic Lateral Sclerosis (ALS) diagnosis can take 10-16 months from symptom onset, leading to delays in treatment and patient counselling. We studied the impact of clinical and genetic risk factors on the diagnostic timeline of ALS. METHODS: Baseline characteristics, family history, gene testing, onset location, time from symptom onset to diagnosis, and time from first doctor visit to suspected ALS was collected. We used multiple regression to assess the interaction of these factors on ALS diagnostic timeline. We analysed a subgroup of patients with genetic testing and compared positive or negative tests, sporadic or familial and ALS-related genes to time for diagnosis. RESULTS: Four hundred and forty-eight patients diagnosed with ALS at the University of Massachusetts Chan Medical Center between January 2007 and December 2021 were analysed. The median time to ALS diagnosis was 12 months and remained unchanged from 2007 to 2021 (p = 0.20). Diagnosis was delayed in patients with sporadic compared with familial ALS (mean months [standard deviation], 16.5[13.5] and 11.2[8.5], p < 0.001); cognitive onset (41[21.26]) had longer time to diagnosis than bulbar (11.9[8.2]), limb (15.9[13.2]), respiratory (19.7[13.9]) and ALS with multiple onset locations (20.77[15.71], p < 0.001). One hundred and thirty-four patients had gene testing and 32 tested positive (23.8%). Gene testing (p = 0.23), a positive genetic test (p = 0.16), different ALS genes (p = 0.25) and sporadic (p = 0.92) or familial (p = 0.85) ALS testing positive for ALS genes did not influence time to diagnosis. DISCUSSION: Time for ALS diagnosis remained unchanged from 2007 to 2021, bulbar-onset and familial ALS made for faster diagnosis.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Testes Genéticos/métodos , Adulto , Diagnóstico Tardio , Fatores de Tempo
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