Expression of N-methyl-D-aspartic acid receptor and endoplasmic reticulum stress related pathway proteins in brain tissue of fluorosis rats / 中国组织工程研究

BACKGROUND:Previous studies have shown that N-methyl-D-aspartic acid receptor(NMDA)receptors are associated with fluorine,but the role in fluoride-induced endoplasmic reticulum stress remains unclear. OBJECTIVE:To observe the changes of excitatory neurotransmitter NMDA receptor and endoplasmic reticulum stress IRE1α-ASK1-JNK pathway protein expression in brain tissue of rats with experimental fluorosis,and to investigate the pathogenesis of neurological injury in fluorosis by giving NMDA receptor inhibitor to SH-SY5Y cells. METHODS:(1)Animal model:18 1-month-old SD rats were randomly divided into control group(drinking water fluoride content<0.5 mg/L),low fluoride group(drinking water fluoride content 10.0 mg/L)and high fluoride group(drinking water fluoride content 100.0 mg/L),with 6 rats in each group,half of each sex.After 6 months of fluoride intake,the rats were observed for the occurrence of dental fluorosis,and the 24-hour urinary fluoride content was measured.After anesthesia and euthanasia,the brain tissue of rats was taken to observe the pathological changes.Western blot assay was used to detect NMDA receptors and IRE1α,ASK1 and JNK protein expression in the brain tissue.(2)Cell model:SH-SY5Y cells were cultured in vitro and treated with sodium fluoride at final concentrations of 0.3 mmol/L and 3 mmol/L.The fluoride-stained cells were interfered with 10 μmol/L NMDA receptor antagonists Ifenprodil and MK-801 to observe the relevant protein changes. RESULTS AND CONCLUSION:(1)The incidence of dental fluorosis and urinary fluoride level in rats in the high fluoride group were significantly higher than that in the control and low fluoride groups(P<0.05).(2)Compared with the control group,the cytoplasm of neuronal cells in the CA3 area of the hippocampus in the low fluoride group was slightly more basophilic,while the neuronal cells in the CA3 area of the high fluoride group were disorganized,with increased basophilicity and some of the nuclei solidified.(3)In rat brain tissue,the expressions of NR2A in the high fluoride group and NR2B in the low fluoride group were significantly higher compared with the control group(P<0.05),and NR2B,IRE1,ASK1,and p-JNK protein expression levels were increased in the high fluoride group compared with the control and low fluoride groups(P<0.05).(4)In SH-SY5Y cells,NR1,NR2A and NR2B protein expressions were significantly increased in the high fluoride group compared to the control group(P<0.05).The protein levels of NR1 and NR2A were significantly reduced in the high fluorine + Ifenprodil group and high fluorine + MK-801 group compared with the high fluorine group(P<0.05).NR2B protein expression was significantly lower in the high fluorine + Ifenprodil group than that in the high fluorine group(P<0.05).(5)In SH-SY5Y cells,IRE1,ASK1,and p-JNK protein expression was significantly higher in the high fluoride group compared with the control group(P<0.05),while ASK1 and p-JNK protein expressions were significantly decreased in the high fluorine + Ifenprodil group and high fluorine + MK-801 group compared with the high fluorine group(P<0.05).IRE1 protein level was significantly lower in the high fluorine + Ifenprodil group than that in the high fluorine group(P<0.05).(6)It is concluded that excessive fluorine intake activates NMDA receptors in the central nervous system,causing increased expression of endoplasmic reticulum stress IRE1α,ASK1,and p-JNK proteins,and the use of NMDA receptor inhibitors has a mitigating effect on endoplasmic reticulum stress caused by fluorosis.

Autoimmune diseases related to anti-N-methyl-D-aspartate receptor encephalitis, a descriptive study in a third level center

Background: Epiphenomena in neurological disorders can lead to subsequent autoimmune diseases such as autoimmune encephalitis (AE), but research on this condition is limited. There is a lack of knowledge about the development of autoimmune diseases in AE patients due to its rarity. The objective of this study is to investigate the association between the development of autoimmune diseases and patients with anti-NMDA autoimmune encephalitis. Methods: A cross-sectional study was conducted from 2015 to 2022 at UMAE La Raza Antonio Fraga Mouret to investigate the relationship between autoimmune diseases and anti-NMDA AE. 194 patients were tested for anti-NMDA antibodies in cerebrospinal fluid (CSF), and 50 were found to meet the criteria for AE based on clinical, laboratory, and imaging tests. Follow-up evaluations assessed for rheumatological diseases and various additional tests were conducted before and after the AE event. The study was approved by the ethical and investigation committee. Results: Our analysis included 50 patients with autoimmune encephalitis. Of these, 62% were women aged 18-51 years (mean age 31.97 years) and 38% were men aged 19-72 years (mean age 39.2 years). Fifty-two percent of patients had positive antibodies for autoimmune diseases, but only 12% met ACR criteria for autoimmune disease. The CSF was negative for infections. Electroencephelography (EEG) showed abnormalities in 42% of patients, and Magnetic resonance imaging (MRI) showed hyperintensity in the medial temporal lobes, cortico-subcortical regions, and white matter. False positives were excluded. Conclusions: Among patients with autoimmune encephalitis, 12% had associated autoimmune diseases, most of which developed after the diagnosis of encephalitis. The observed diseases were 3 cases of lupus, 1 of rheumatoid arthritis, 1 of thyroiditis, and 1 of vasculitis. There is an epiphenomenal relationship between autoimmune encephalitis and subsequent development of autoimmune diseases.

Ketamine but not glycine potentiates antidepressant like action of citalopram in mice exposed to chronic mild stress

Background: The present study was designed to investigate the effect of citalopram, ketamine, glycine and their combinations on animal models of depression. Methods: Swiss Albino male mice were subjected to chronic mild stress for 6 weeks for inducing depression, and randomly divided into different groups: citalopram (5 and 10 mg/kg), ketamine (17.5 and 35 mg/kg), glycine (50 and 100 mg/kg), ketamine (17.5 mg/kg) + citalopram (5 mg/kg) and ketamine (17.5 mg/kg) + glycine (50 mg/kg). Two behavioural tests were utilized for the assessment of depression, namely tail suspension test (TST) and forced swim test (FST). Immobility time was recorded for 6 min, before and after administration of drug. Results: Citalopram (10 mg/kg) administration caused significant decrease in the immobility time in TST model only but not in FST. Citalopram (5 mg/kg) and ketamine (17.5 mg/kg) caused insignificant decrease in immobility time in both the models. Moreover, ketamine in combination with Citalopram significantly reduced the immobility time in both the models. Glycine at a dose of 100 mg/kg (but not 50 mg/kg) significantly increased the immobility time in both the models as compared to control group. Further, ketamine when administered with glycine caused increase in the immobility time on both the paradigms, though insignificant. Conclusions: Ketamine demonstrated antidepressant like action in both TST and FST models. Moreover, it potentiated the antidepressant effect of citalopram that might be due to the role of NMDA receptors.

Clínicas de ketamina: usos actuales según la evidencia / Ketamine clinics: current uses based on evidence

Resumen: La ketamina es un medicamento conocido por sus bondades como inductor anestésico y para disminuir la posibilidad de complicaciones, por ejemplo, exacerbación del dolor neuropático e hiperalgesia asociada a opioides. En esta revisión nos enfocaremos en otras indicaciones en las que también ha demostrado ser útil y que, bajo observación e instrucción adecuadas en una infraestructura diseñada para ello (clínicas de ketamina), mejora la calidad en el comportamiento y disminuye el estrés, ansiedad y dolor. Entre las indicaciones para su uso se encuentran los trastornos depresivos, el trastorno de ansiedad, el trastorno obsesivo compulsivo y los relacionados con traumas emocionales; el trastorno bipolar, anormalidades en conducta e ingesta alimentaria, al igual que los trastornos adictivos.

Abstract: Ketamine is a drug known for its benefits as an anesthetic inducer and to reduce the possibility of complications such as exacerbation of neuropathic pain and hyperalgesia associated with opioids. In this review we will focus on other indications in which it has also proven to be useful and that, under adequate observation and instruction in an infrastructure designed for it (ketamine clinics), improves the quality of behavior and decreases stress, anxiety and pain. Among the indications for its use are depressive disorders, anxiety disorder, obsessive-compulsive disorder and those related to emotional trauma; bipolar disorder, abnormalities in behavior and eating intake as well as addictive disorders.

Secuelas cognitivas en encefalitis inmunomediadas: cohorte de pacientes en Argentina / Cognitive sequelae in immunomediated encephalitis: cohort of patients in Argentina

Resumen Introducción: Las encefalitis inmunomediadas son un desorden neurológico de origen autoinmune. Actual mente es escasa la descripción de las secuelas cognitivas crónicas. El objetivo del presente trabajo fue caracterizar la secuela cognitiva de diferentes tipos de encefalitis inmunomediadas en una cohorte de un centro único de Argentina. Métodos: Estudio prospectivo, observacional, trans versal, de pacientes en seguimiento en un hospital de la Ciudad de Buenos Aires, con diagnóstico de encefalitis inmunomediada probable y definitiva. Se evaluaron variables epidemiológicas, clínicas, paraclínicas y tra tamiento. Se determinó la secuela cognitiva a través de una evaluación neurocognitiva realizada a partir del año de la presentación clínica. Resultados: Fueron incluidos 15 pacientes, todos con resultado disminuido en al menos un test. La memoria fue el dominio más afectado. Aquellos que se encon traban bajo tratamiento inmunosupresor al momento de evaluarse presentaron menores resultados en el aprendizaje seriado (media -2.94; desvío estándar 1.54) versus los que se encontraban sin tratamiento (media -1.18; desvío estándar 1.40; p = 0.05) y en la prueba de reconocimiento (media -10.34; desvío estándar 8.02) ver sus sin tratamiento (media -1.39; desvío estándar 2.21; p = 0.003). Los pacientes con estatus epiléptico tuvieron resultados deficitarios en la prueba de reconocimiento (media -7.2; desvío estándar 7.91) en comparación a los que no lo tenían (media -1.47; desvío estándar 2.34; p = 0.05). Conclusión: Nuestros resultados demuestran que, a pesar del curso monofásico de la enfermedad, todos los pacientes presentan daño cognitivo persistente más allá del año del inicio del cuadro. Estudios prospectivos de mayor envergadura serían necesarios para confirmar nuestros hallazgos.

Abstract Introduction: Autoimmune encephalitis represents a group of immune-mediated neurological disorders. At present, the description of the chronic cognitive sequela is scarce. The objective of this study was to characterize the cognitive after effects of different types of autoimmune encephalitis in a cohort from a single center in Argentina. Methods: Prospective, observational, cross-sectional study of patients under follow-up at a hospital in Buenos Aires city, with a diagnosis of probable and definitive immune-mediated encephalitis. Epidemiological, clini cal, paraclinical and treatment related variables were evaluated. Cognitive sequela was determined through a neurocognitive evaluation performed at least a year after the clinical presentation. Results: Fifteen patients were included. All had di minished results in at least one test. Memory was the most affected domain. Patients who were under im munosuppressive treatment at the time of evaluation presented lower results in serial learning (mean -2.94; standard deviation 1.54) versus those who weren't under treatment (mean -1.18; standard deviation 1.40; p = 0.05). The same pattern was observed on the recognition test of treatment group (mean -10.34; standard deviation 8.02) versus treatment-free group (mean -1.39; standard deviation 2.21; p =0.003). Patients with status epilepticus had poorer results in the recognition test (mean -7.2; standard deviation 7.91) compared to those without it (mean -1.47; standard deviation 2.34; p = 0.05). Conclusion: Our results show that, despite the mo nophasic course of this disease, all patients had persis tent cognitive damage beyond the year of onset. Larger prospective studies are required to confirm our findings.

Neurolupus como manifestación de primer brote psicótico Reporte de caso / Neurolupus as a manifestation of the first psychotic episode: case report

Resumen Antecedentes: El lupus eritematoso sistémico (LES) es una enfermedad auto inmunitaria crónica multisistémica con diversas manifestaciones clínicas. Siendo las mujeres la pobla ción vulnerable y con mayor afectación a nivel neurológico, al presentar mayor riesgo de convulsiones. Las manifestaciones neuropsiquiátricas ocurren en etapas tempranas de la enfermedad y del diagnóstico, ya que pueden presentarse junto con manifestaciones sistémicas o no. La frecuencia de manifestaciones neuropsiquiátricas en el lupus eritematoso sistémico se ha descrito del 14 al 75%, siendo las alteraciones cognitivas uno de los grandes síntomas a destacar1. La cual puede ir acompañada de trastornos afectivos de tipo depresión y ansiedad. Ya que la psicosis secundaria a LES se remarca por su baja prevalencia (10%)2, los estudios de laboratorio nos suelen orientar hacia el diagnóstico definitivo, siendo los anticuerpos ribosomales P los que se han relacionado más específicamente con la psicosis lúpica. La resonancia magnética es la prueba de elección y las lesiones cerebrales están dominadas por hiperintensidades de materia blanca en forma de punción3. En el siguiente reporte de caso, presentamos a una paciente de 20 años, la cual contaba con antecedentes de esteatosis hepática diagnosticado, diabetes tipo MODY y resección de ovario derecho por teratoma maduro de 9 años de evolución, pero sin antecedentes psiquiátricos de importancia para el momento de su valoración. Sin embargo, de forma aguda presentó un brote psicótico caracterizado por ideas delirantes de grandiosidad y referencia, así como alteraciones conductuales, cognitivas y afectivas. Por las que tuvieron que acudir a hospital de 3er nivel durante el periodo de contingencia sanitaria en el 2020. Tras el antecedente de presentar infección por SARS-CoV-2 tres meses antes de su patología neuropsiquiátricas. Se sospechó en síntomas neurológicos secundarios a infección por COVID-19, así como patología psiquiátrica aislada. Por lo que se realizó abordaje de estudio de primer brote psicótico, diagnosticándose lupus eritematoso sistémico con manifestaciones neuropsiquiátricas. El tratamiento se basó en un bolo de metilprednisolona y antipsicóticos, luego modificada por terapia con corticoesteroides orales y antipsicótico de depósito. Conclusión: El lupus eritematoso sistémico con manifestaciones neuropsiquiátricas es una presentación poco frecuente del padecimiento, por la amplia variación en la aparición de este, los pacientes con síntomas psiquiátricos en contexto de hospital general deben de ser tomados en cuenta para abordajes extensos4. De la misma forma, el tener este conocimiento del caso podrá ampliar nuestro conocimiento sobre las complicaciones de esta patología reumatológica. Y una de sus complicaciones más graves como la psicosis lúpica para poder realizar un mejor abordaje del primer brote psicótico en hospitales generales, donde la valoración de un especialista puede ser más complicada para mejorar las condiciones médicas de estos pacientes.

Abstract Background: Systemic lupus erythematosus is a chronic multisystemic autoimmune disease with diverse clinical manifestations. Women are the most vulnerable population and have the greatest neurological involvement with a higher risk of seizures. Neuropsychiatric manifestations occur in early stages of the disease and diagnosis since they can occur together with systemic manifestations or not. The frequency of neuropsychiatric manifestations in systemic lupus erythematosus has been described from 14 to 75%; being cognitive alterations one of the major symptoms to highlight. Which, in the same way can be accompanied by affective disorders such as depression and anxiety. Since psychosis, secondary to SLE, stands out for its low prevalence (10%), laboratory studies usually guide us towards a definitive diagnosis, being ribosomal P antibodies the ones that have been more specifically related to lupus psychosis. MRI is the test of choice and brain lesions are dominated by punctate white matter hyperintensities. In the following case report, we present a 20-year-old patient who had a history of diagnosed hepatic steatosis, MODY type diabetes and resection of the right ovary for mature teratoma of 9 years of evolution; but with no psychiatric history of importance at the time of her evaluation. However, she acutely presented a psychotic outbreak characterized by delusions of grandiosity and reference; as well as behavioral, cognitive, and affective alterations. For which she had to go to a 3rd level hospital during the period of health contingency in 2020. After a history of SARS-CoV-2 infection three months before her neuropsychiatric pathology, neurological symptoms secondary to COVID-19 infection were suspected, as well as isolated psychiatric pathology. Therefore, a study approach of the first psychotic outbreak was performed, diagnosing systemic lupus erythematosus with neuropsychiatric manifestations. Treatment was based on a bolus of methylprednisolone and antipsychotics; later modified by therapy with oral corticosteroids and depot antipsychotic. Conclusion: Systemic lupus erythematosus with neuropsychiatric manifestations is an infrequent presentation of the disease, because of the wide variation in its appearance, patients with psychiatric symptoms in a general hospital setting should be considered for extensive approaches. In the same way, having this knowledge of this case may broaden our knowledge about the complications of this rheumatologic pathology. And one of its most serious complications such as lupus psychosis to be able to make a better approach to the first psychotic outbreak in general hospitals, where the assessment of a specialist can be more complicated.

Celastrus paniculatus and memantine prevent alcohol dependence and improve decision making in alcohol dependent C57BL6 mice

Background: Alcohol use disorder poses a huge burden with only a handful of approved drugs. AUD is associated with impaired decision-making that leads to compulsive drinking despite negative consequences. A drug that decreases alcohol consumption as well as improves decision-making may thus prove more useful. This study was planned to evaluate the effect of two drugs, Celastrus paniculatus and memantine on alcohol preference and decision impairment in alcohol-dependent mice. Methods: In part 1, the effect of both the study drugs on alcohol consumption was studied using intermittent access model in 70 male C57BL6 mice. In part 2, effect of drugs on decision making was studied using the rodent version of Iowa gambling task. Mice were divided in seven study groups: Group 1-3: Celastrus paniculatus (140, 280, and 560 mg/kg), Group 4: memantine (25 mg/kg), Group 5: vehicle control 1 (Milk), Group 6: vehicle control 2 (normal saline) and Group 7: naltrexone(1mg/kg). Results: Percentage alcohol preference was lower in test groups i.e., Celastrus paniculatus at medium (40.90±15.18%) and high doses (31.79±7.46%) vs. milk (82.74±8.53%; p<0.05); and in memantine group (36.28±10.99%) vs. normal saline (83.27±5.51%; p<0.05). The results were not significantly different to Naltrexone (19.70±6.90%). Percentage preference to disadvantageous arms was also lower in Celastrus paniculatus, at medium (50.52±1.92%) and high doses (48.11±2.43%) compared to milk (54.47±2.73%; p<0.05) and memantine (47.45±1.67%) compared to normal saline (54.00±2.73%; p<0.05), indicating better decision-making ability in the test groups. The findings were comparable to Naltrexone group (45.43±2.52%). Conclusions: These results indicate that Celastrus paniculatus and memantine reduce alcohol consumption and improve decision making in alcohol-dependent mice.

Research progress on the role of NMDA receptors in migraine / 中风与神经疾病杂志

@#N­methyl­D-aspartate （NMDA） receptors are ionotropic glutamate receptors that are widely expressed in the central nervous system.Through mediating Ca2+ influx for excitatory synaptic transmission，NMDA receptors play an important role in synaptic plasticity，learning，and memory.Migraine is a common primary headache that brings serious life and mental burdens to patients because of frequent attacks.The pathogenesis of migraine is still unclear.Glutamate and NMDA receptors have been demonstrated to be closely related to the occurrence of migraine.This paper reviews progress on the association of NMDA receptors with migraine and the use of NMDA receptor antagonists for the prevention and treatment of migraine，aiming to provide a reference for the pathogenesis and drug treatment of migraine.

Therapeutic efficacy of novel memantine nitrate MN-08 in animal models of Alzheimer's disease and vascular dementia / 中国药理学与毒理学杂志

OBJECTIVE Alzheimer's disease(AD)and vascular dementia(VD)are the primary causes of dementia in elderly individuals,and therapeutic options for both conditions are limited.Overactivation of N-methyl-D-aspartate(NMDA)receptors,decreased cerebral blood flow,and subsequent pathological events,play signifi-cant roles in the progression of AD and VD.METHODS In this study,we investigated the therapeutic effects and underlying mechanisms of MN-08,a novel memantine nitrate,in mouse models of AD and rats with VD.RESULTS MN-08 was found to inhibit Aβ accumulation,prevent neuronal and dendritic spine loss,and attenuate cognitive deficits in 2-month-old APP/PS1 transgenic mice(following a 6-month preventative course)and in 8-month-old triple-transgenic(3×Tg-AD)mice(following a 4-month therapeutic course),as well as in rat models of VD with preventive and therapeutic treatments.In vitro,MN-08 was shown to bind to and antagonize NMDA receptors,inhibit calcium influx,and reverse dysregula-tions of the ERK and PI3K/Akt/GSK3β pathway,subse-quently preventing glutamate-induced neuronal loss.Additionally,MN-08 exhibited favorable pharmacokinet-ics,blood-brain barrier penetration,and safety profiles in rats and beagle dogs.CONCLUSION These findings suggest that the novel memantine nitrate MN-08 may be a useful therapeutic agent for AD and VD.

Effect of NMDA receptor blocker in relieving HIV-1/gp120 induced learning and memory disorder in rats and its mechanism / 中国药理学通报

Aim: To investigate the alleviating effect of NMDA receptor blocking on learning and memory impairment induced by gp120 in rats and its mechanism. Methods: (1 ) Thirty-two SD rats were randomly divided into control group, sham operation group, gpl20 group, and gp120 + Memantine group. Except for the control group, the other groups underwent a bilateral hippocampal injection to establish the model of learning and memory impairment in rats. Memantine (10 mg • kg

Progress on the impact of pathogenic gene mutations in epilepsy on treatment choices / 国际儿科学杂志

In the past decade, significant progress has been made in the study of epilepsy-causing genetic mutations and the molecular mechanisms of epilepsy clinical manifestations.A growing number of studies have shown that the mechanism of action of pathogenic genes related to clinical symptoms shows significant correlation.In the selection of antiepileptic drugs for patients with different gene mutation, early identification of pathogenic genes has guiding significance for the selection of antiepileptic drugs.This review summairzes common epilepsy pathogenic genes, including ion channels genes, cellular metabolism related genes and cell signaling pathway related genes, and research progress on therapeutic targets corresponding to pathogenic genes in recent years.As research deepens, specific gene defects and their machanisms of action provide a basis for studying new treatment methods.

Brain-derived neurotrophic factor serum levels following ketamine and esketamine intervention for treatment-resistant depression: secondary analysis from a randomized trial

Abstract Objectives Evidence suggests that ketamine's influence on brain-derived neurotrophic factor (BDNF) might be involved in its mechanism of rapid antidepressant action. We aimed to evaluate the differential impact of ketamine and esketamine on serum BDNF levels and its association with response patterns in treatment-resistant depression (TRD). Methods Participants (n = 53) are from a randomized, double-blind clinical trial comparing the efficacy of single-dose ketamine (0.5mg/kg, n = 27) and esketamine (0.25mg/kg, n = 26) in TRD. Depression severity was assessed before and 24 hours, 72 hours, and 7 days after the intervention, using the Montgomery-Åsberg Depression Rating Scale (MADRS). Blood samples were collected before infusion, 24 hours, and 7 days afterwards. Results There were no significant changes in BDNF levels at post-infusion evaluation points, and no difference in BDNF levels comparing ketamine and esketamine. Both drugs exhibited similar therapeutic effect. There was no association between BDNF levels and response to treatment or severity of depressive symptoms. Conclusion There was no significant treatment impact on BDNF serum levels - neither with ketamine nor esketamine - despite therapeutic response. These results suggest that ketamine or esketamine intervention for TRD has no impact on BDNF levels measured at 24 hours and 7 days after the infusion. This clinical trial is registered on the Japan Primary Registries Network: UMIN000032355.

Does mismatch negativity have utility for NMDA receptor drug development in depression?

Rapid antidepressant effects associated with ketamine have shifted the landscape for the development of therapeutics to treat major depressive disorder (MDD) from a monoaminergic to glutamatergic model. Treatment with ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, may be effective, but has many non-glutamatergic targets, and clinical and logistical problems are potential challenges. These factors underscore the importance of manipulations of binding mechanics to produce antidepressant effects without concomitant clinical side effects. This will require identification of efficient biomarkers to monitor target engagement. The mismatch negativity (MMN) is a widely used electrophysiological signature linked to the activity of NMDA receptors (NMDAR) in humans and animals and validated in pre-clinical and clinical studies of ketamine. In this review, we explore the flexibility of the MMN and its capabilities for reliable use in drug development for NMDAR antagonists in MDD. We supplement this with findings from our own research with three distinct NMDAR antagonists. The research described illustrates that there are important distinctions between the mechanisms of NMDAR antagonism, which are further crystallized when considering the paradigm used to study the MMN. We conclude that the lack of standardized methodology currently prevents MMN from being ready for common use in drug discovery. Clinical trial registration: This manuscript describes data collected from the following National Institutes of Health (NIH) and Veterans Affairs (VA) studies: AV-101, NCT03583554; lanicemine, NCT03166501; ketamine, NCT02556606.

A novel cell tool for α2δ-1-NMDAR target-based analgesic drug discovery / 生物工程学报

The α2δ-1 protein coded by Cacna2d1 is dramatically up-regulated in dorsal root ganglion (DRG) neurons and spinal dorsal horn following sensory nerve injury in various animal models of neuropathic pain. Cacna2d1 overexpression potentiates presynaptic and postsynaptic NMDAR activity of spinal dorsal horn neurons to cause pain hypersensitivity. The α2δ-1-NMDAR interaction promotes surface trafficking and synaptic targeting of NMDARs in neuropathic pain caused by chemotherapeutic agents and peripheral nerve injury, as well as in other pathological conditions such as in the paraventricular nucleus (PVN) with neurogenic hypertension and in the brain with ischemic stroke. The lentiviral transfection method was used to construct a human embryonic kidney HEK293T cell line that could stably express α2δ-1-NMDAR complex. A stably transfected cell line was observed by florescence microscope, and identified by RT-qPCR and Western blotting. The results showed that the HEK293T cell line was successfully transfected and the genes could be stably expressed. Subsequently, the transfected cell line was successfully developed into a target drug screening system using patch clamp techniques. It provides a promising cell model for further research on the interaction mechanism of α2δ-1-NMDAR complex and drug screening for chronic pain and related diseases with low side effects.

AMPA and angiotensin type 1 receptors are necessary for hemorrhage-induced vasopressin secretion

Hypovolemia induced by hemorrhage is a common clinical complication, which stimulates vasopressin (AVP) secretion by the neurohypophysis in order to retain body water and maintain blood pressure. To evaluate the role of brain L-glutamate and angiotensin II on AVP secretion induced by hypovolemia we induced hemorrhage (∼25% of blood volume) after intracerebroventricular (icv) administration of AP5, NBQX, or losartan, which are NMDA, AMPA, and AT1 receptor antagonists, respectively. Hemorrhage significantly increased plasma AVP levels in all groups. The icv injection of AP5 did not change AVP secretion in response to hemorrhage. Conversely, icv administration of both NBQX and losartan significantly decreased plasma AVP levels after hemorrhage. Therefore, the blockade of AMPA and AT1 receptors impaired AVP secretion in response to hemorrhage, suggesting that L-glutamate and angiotensin II acted in these receptors to increase AVP secretion in response to hemorrhage-induced hypovolemia.

In silico investigation on the probable macromolecular drug targets involved in the anti-schizophrenia activity of Nardostachys jatamansi

Abstract Existing medications i.e. the antipsychotic drugs are known to be effective in treating only the positive symptoms of schizophrenia, while being ineffective on negative and cognitive symptoms of the disease. In addition, these medications cause extrapyramidal symptoms, forcing many patients towards natural medicine in the hope of minimizing the unwanted adverse effects. Nardostachys jatamansi is a medicinal plant that has been traditionally prescribed for various types of brain disorders. The active constituents of the plant have beneficial effects on the negative and cognitive symptoms of schizophrenia. This study was designed to identify the active constituents of Nardostachys jatamansi with the highest binding affinities for the key macromolecular drug targets involved in the pathophysiology of schizophrenia and thereby elucidate the possible mechanism of action. These targets are dopamine receptors, Gamma-aminobutyric acid receptors, N-methyl-D-aspartate receptors and Phosphodiesterase 10A. The results of molecular docking showed that, β-sitosterol, chlorogenic acid, oleanic acid and ursolic acid, displayed high binding affinity toward all the macromolecular drug targets. Ligands with steroid backbone and pentacyclic triterpene structure have been found to possess high binding affinity toward the dopamine receptor and phosphodiesterase 10A. While ligands with carbonyl group form stronger binding interactions with the N-methyl-D-aspartate receptor.

Nitrous oxide as an adjunctive therapy in major depressive disorder: a randomized controlled double-blind pilot trial

Objective: Major depressive disorder (MDD) is related to glutamatergic dysfunction. Antagonists of glutamatergic N-methyl-D-aspartate receptor (NMDAR), such as ketamine, have antidepressant properties. Nitrous oxide (N2O) is also a NMDAR antagonist. Thus, this study aimed to evaluate the effects of augmenting antidepressant treatment with N2O. Methods: This double blind, placebo-controlled randomized parallel pilot trial was conducted from June 2016 to June 2018 at the Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo. Twenty-three subjects with MDD (aged 18 to 65, on antidepressants, with a score > 17 on the 17-item-Hamilton Depression Rating Scale [HAM-D17]) received 50% N2O (n=12; 37.17±13.59 years) or placebo (100% oxygen) (n=11; 37.18±12.77 years) for 60 minutes twice a week for 4 weeks. The primary outcome was changes in HAM-D17 from baseline to week 4. Results: Depressive symptoms improved significantly in the N2O group (N2O: from 22.58±3.83 to 5.92±4.08; placebo: from 22.44±3.54 to 12.89±5.39, p < 0.005). A total of 91.7% and 75% of the N2O group subjects achieved response (≥ 50% reduction in HAM-D17 score) and remission (HAM-D17 < 7), respectively. The predominant adverse effects of N2O treatment were nausea, vomiting, and headache. Conclusion: N2O treatment led to a statistically significant reduction in HAM-D17 scores compared to placebo. Clinical trial registration: Brazilian Register of Clinical Trials, RBR-5rz5ch

Anestesia intravenosa contínua com cetamina racêmica ou dextrocetamina e detomidina em cadelas / [Continuous intravenous anesthesia with racemic ketamine or dextroketamine and detomidine in female dogs]

Objetivou-se com este estudo comparar a associação de detomidina e cetamina ou dextrocetamina, por via intravenosa contínua, em oito cadelas submetidas a dois protocolos: GCD - indução anestésica com 5mg/kg e infusão intravenosa contínua de 20mg/kg/h de cetamina; e GDD - indução com 3,5mg/kg e infusão de 14mg/kg/h de dextrocetamina. Associou-se detomidina, 30µg/kg/h, em ambos os grupos. Registraram-se frequência cardíaca (FC), pressão arterial (PA), frequência respiratória (f), temperatura (TC), miorrelaxamento, analgesia, hemogasometria e eletrocardiograma, antes e 15 minutos após a MPA (Mbasal e Mmpa); após o início da infusão (Mic); a cada 10 minutos até 90 minutos (M10, M20, M30, M40, M50, M60, M70, M80 e M90); e 30 minutos após o fim da infusão (M120). Foi observada bradicardia em Mmpa no GCD e de Mmpa a M10 no GDD. Ocorreu hipotensão em Mmpa e hipertensão a partir de Mic. A f diminuiu de M10 a M30. Foram observados: onda T de alta amplitude, bloqueios atrioventriculares e parada sinusal. Ocorreu acidose respiratória. O período de recuperação foi de 219,6±72,3 minutos no GCD e de 234,1±96,8 minutos no GDD. A cetamina e a dextrocetamina, associadas à detomidina por infusão contínua, causam efeitos cardiorrespiratórios e anestésicos similares.(AU)

The combination of detomidine and ketamine or dextrocetamine for continuous intravenous infusion was compared in eight female dogs submitted to two protocols: GCD - 5mg/kg of anesthetic induction and continuous intravenous infusion of ketamine 20mg/kg/h; and GDD - induction with 3.5mg/kg and infusion of 14mg/kg/h of dextrocetamine. Detomidine, 30µg/kg/h was associated in both groups. Heart rate (HR), blood pressure (BP), respiratory rate (RR), temperature (CT), myorelaxation, analgesia, blood gas analysis and electrocardiogram were recorded before and 15 minutes after MPA (Mbasal and Mmpa); after the start of infusion (Mic); every 10 minutes to 90 minutes (M10, M20, M30, M40, M50, M60, M70, M80 and M90); and 30 minutes after the end of infusion (M120). Bradycardia was observed in Mmpa in GCD and from Mmpa to M10 in GDD. There was hypotension in Mmpa and hypertension from Mic. The RR decreased from M10 to M30. High amplitude T wave, atrioventricular blocks and sinus arrest were observed. Respiratory acidosis occurred. The recovery period was 219.6±72.3 minutes in GCD and 234.1±96.8 minutes in GDD. Ketamine and S+ ketamine associated with detomidine for continuous infusion cause cardiorespiratory and similar anesthetic effects.(AU)

Encefalitis por Anticuerpos contra el Receptor NMDA: un diagnóstico diferencial neuropsiquiátrico

La Encefalitis por Anticuerpos contra el Receptor NMDA es un reto debido a la amplia lista de posibilidades diagnósticas a las que se asemeja la sintomatología inicial. Es una enfermedad cuya fisiopatología está dada por la generación y acción de anticuerpos, inducidos mayormente por agentes externos (virus) e internos (algunos tumores), sobre NMDAR (receptor N-metil-D-aspartato) que puede cursar con alteraciones neurológicas, psiquiátricas y autonómicas, usualmente afectando a población femenina adulta joven y que en ocasiones forma parte de un síndrome paraneoplásico. Su manejo se basa en inmunoterapia con corticosteroides, inmunoglobulina intravenosa o en casos refractarios, plasmaféresis. La eficacia de estas terapias aumenta con el diagnóstico oportuno, sin embargo con frecuencia el tratamiento se aplica tardíamente por lo difícil del acierto diagnóstico. Presentamos el caso clínico de una femenina de 22 años, que debutó con manifestaciones neuropsiquiátricas, inicialmente medicada con antipsicóticos y que desarrolló rigidez, aumento de creatina quinasa y estatus epiléptico, por lo cual se sospechó síndrome neuroléptico maligno, ameritando hospitalización en la unidad de cuidados intensivos. Ante la nula mejoría, se replanteó el diagnóstico, con sospecha de encefalitis autoinmune y se instauró el tratamiento específico, con lo cual la paciente pudo retornar a su vida diaria sin déficit. (provisto por Infomedic International)

Alteration of plasma alanine, glutamate, and glycine Level: A potentiate manic episode of bipolar disorder

@#Introduction: The amino acids that function as co-agonists at the N-methyl-D-aspartate (NMDA) receptor have been investigated in bipolar disorder (BD). However, studies comparing amino acid levels in the plasma of BD patients with healthy controls have yielded inconsistent results. We, therefore, conducted a study in Hospital Universiti Sains Malaysia to determine the plasma levels of glutamate, glycine, and alanine in BD patients and compared them with the healthy controls. Materials and Methods: An overnight fast of 10-hour plasma levels of glutamate, glycine, alanine, and tryptophan were measured in 83 bipolar patients, and were compared to a group of 82 healthy controls. Results: The mean (SD) age of bipolar patients was 40.9 (12.1), while the mean (SD) age for control groups was 35.6 (7.7) years. The median (25th, 75th percentile) of glutamate and alanine levels in bipolar patients was 111.0 (65.0,176.0) and 530.0 (446.0,629.0), respectively, while the mean (SD) of glycine level in bipolar patients was 304.0 (98.1). Significant higher glutamate, glycine, and alanine levels were found in bipolar disorder patients in the manic episode as compared to the healthy controls. Conclusion: Although the exact relationship between peripheral NMDA receptor co-agonist levels in the pathogenesis of BD is not well understood, these findings should be explored and may enlighten some new paths for BD therapy which could reward the patients also clinicians.