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1.
Heliyon ; 10(14): e33580, 2024 Jul 30.
Article de Anglais | MEDLINE | ID: mdl-39100491

RÉSUMÉ

The oxidation rate of NO to NO2 is a critical parameter in the removal of NOx within selective catalytic reduction (SCR) systems. LaCoO3-δ is a kind of potential catalyst to enhance the oxidation of NO to NO2, it may offers an economic and stable alternative to noble metal catalysts, particularly at elevated temperatures. This study aimed to enhance the catalytic efficiency of LaCoO3-δ through strontium (Sr) doping. La1-xSrxCoO3-δ (with varying x values of 0.1, 0.2, 0.3, 0.4) was synthesized using a sol-gel method. La1-xSrxCoO3-δ exhibited superior NO oxidation catalytic activity compared to LaCoO3-δ, with the most notable enhancement observed at x = 0.3 (84 % conversion). This improvement can be attributed to the substitution of La3+ with Sr2+, which induces lattice distortion and charge imbalance, thereby creating more oxygen vacancies that enhance the catalytic oxidation capability of La1-xSrxCoO3-δ. However, it's important to note that an excessive amount of Sr can result in the formation of SrCO3 deposits on the surface of La1-xSrxCoO3-δ, thereby diminishing its catalytic oxidation performance. The catalytic oxidation reaction behavior adhered most closely to the O2-adsorbed E-R model, the surface defects in La1-xSrxCoO3-δ playing a pivotal role in the catalytic reaction.

2.
BMJ ; 385: e078218, 2024 04 10.
Article de Anglais | MEDLINE | ID: mdl-38808490

RÉSUMÉ

OBJECTIVE: To determine whether a single low dose of esketamine administered after childbirth reduces postpartum depression in mothers with prenatal depression. DESIGN: Randomised, double blind, placebo controlled trial with two parallel arms. SETTING: Five tertiary care hospitals in China, 19 June 2020 to 3 August 2022. PARTICIPANTS: 364 mothers aged ≥18 years who had at least mild prenatal depression as indicated by Edinburgh postnatal depression scale scores of ≥10 (range 0-30, with higher scores indicating worse depression) and who were admitted to hospital for delivery. INTERVENTIONS: Participants were randomly assigned 1:1 to receive either 0.2 mg/kg esketamine or placebo infused intravenously over 40 minutes after childbirth once the umbilical cord had been clamped. MAIN OUTCOME MEASURES: The primary outcome was prevalence of a major depressive episode at 42 days post partum, diagnosed using the mini-international neuropsychiatric interview. Secondary outcomes included the Edinburgh postnatal depression scale score at seven and 42 days post partum and the 17 item Hamilton depression rating scale score at 42 days post partum (range 0-52, with higher scores indicating worse depression). Adverse events were monitored until 24 hours after childbirth. RESULTS: A total of 364 mothers (mean age 31.8 (standard deviation 4.1) years) were enrolled and randomised. At 42 days post partum, a major depressive episode was observed in 6.7% (12/180) of participants in the esketamine group compared with 25.4% (46/181) in the placebo group (relative risk 0.26, 95% confidence interval (CI) 0.14 to 0.48; P<0.001). Edinburgh postnatal depression scale scores were lower in the esketamine group at seven days (median difference -3, 95% CI -4 to -2; P<0.001) and 42 days (-3, -4 to -2; P<0.001). Hamilton depression rating scale scores at 42 days post partum were also lower in the esketamine group (-4, -6 to -3; P<0.001). The overall incidence of neuropsychiatric adverse events was higher in the esketamine group (45.1% (82/182) v 22.0% (40/182); P<0.001); however, symptoms lasted less than a day and none required drug treatment. CONCLUSIONS: For mothers with prenatal depression, a single low dose of esketamine after childbirth decreases major depressive episodes at 42 days post partum by about three quarters. Neuropsychiatric symptoms were more frequent but transient and did not require drug intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT04414943.


Sujet(s)
Dépression du postpartum , Kétamine , Humains , Femelle , Kétamine/administration et posologie , Kétamine/effets indésirables , Adulte , Méthode en double aveugle , Grossesse , Dépression du postpartum/traitement médicamenteux , Dépression du postpartum/prévention et contrôle , Antidépresseurs/administration et posologie , Antidépresseurs/usage thérapeutique , Antidépresseurs/effets indésirables , Trouble dépressif majeur/traitement médicamenteux , Trouble dépressif majeur/prévention et contrôle , Chine/épidémiologie , Résultat thérapeutique , Complications de la grossesse/psychologie , Complications de la grossesse/traitement médicamenteux , Échelles d'évaluation en psychiatrie , Mères/psychologie
3.
Med Biol Eng Comput ; 59(5): 1099-1110, 2021 May.
Article de Anglais | MEDLINE | ID: mdl-33881705

RÉSUMÉ

There is now a relatively large body of evidence suggesting a relationship between dysfunction of myelin and oligodendrocytes and the etiology of several neuropsychiatric disorders, including depression and schizophrenia, and also suggesting that ultrasound methods may alleviate some of the symptoms of depression. We have applied low-intensity pulsed ultrasound (LIPUS) to the brains of mice treated with the demyelinating drug cuprizone, a drug that has been used as the basis for a rodent model relevant to a number of psychiatric and neurologic disorders including depression, schizophrenia, and multiple sclerosis. Prior to conducting the studies in mice, preliminary studies were carried out on the effects of LIPUS in vitro in neuron-like SH-SY5Y cells and primary glial cells. In subsequent studies in mice, female C57BL/6 mice were restrained in plastic tubes for 20 min daily with the ultrasound transducer near the end of the tube directly above the mouse's head. LIPUS was used at an intensity of 25 mW/cm2 once daily for 22 days in control mice and in mice undergoing daily repetitive restraint stress (RRS). Behavioral or neurochemical studies were done on the mice or the brain tissue obtained from them. The studies in vitro indicated that LIPUS stimulation at an intensity of 15 mW/cm2 delivered for 5 min daily for 3 days in an enclosed sterile cell culture plate in an incubator increased the viability of SH-SY5Y and primary glial cells. In the studies in mice, LIPUS elevated levels of doublecortin, a marker for neurogenesis, in the cortex compared to levels in the RRS mice and caused a trend in elevation of brain levels of brain-derived neurotrophic factor in the hippocampus relative to control levels. LIPUS also increased sucrose preference (a measure of the attenuation of anhedonia, a common symptom of several psychiatric disorders) in the RRS model in mice. The ability of LIPUS administered daily to rescue damaged myelin and oligodendrocytes was studied in mice treated chronically with cuprizone for 35 days. LIPUS increased cortex and corpus callosum levels of myelin basic protein, a protein marker for mature oligodendrocytes, and neural/glial antigen 2, a protein marker for oligodendrocyte precursor cells, relative to levels in the cuprizone + sham animals. These results of this exploratory study suggest that future comprehensive time-related studies with LIPUS on brain chemistry and behavior related to neuropsychiatric disorders are warranted. Exploratory Study on Neurochemical Effects of Low Intensity Pulsed Ultrasound in Brains of Mice. Upper part of figure: LIPUS device and in-vitro cell experimental set-up. The center image is the LIPUS generating box; the image in the upper left shows the cell experiment set-up; the image in the upper right shows a zoomed-in sketch for the cell experiment; the image in the lower left shows the set-up of repetitive restraint stress (RRS) with a mouse; the image in the lower middle shows the set-up of LIPUS treatment of a mouse; the image in the lower right shows a zoomed-in sketch for the LIPUS treatment of a mouse.


Sujet(s)
Sclérose en plaques , Ondes ultrasonores , Animaux , Encéphale , Femelle , Souris , Souris de lignée C57BL , Gaine de myéline
4.
Biomed Pharmacother ; 111: 1467-1477, 2019 Mar.
Article de Anglais | MEDLINE | ID: mdl-30841462

RÉSUMÉ

Tripterygium wilfordii Hook. F. is a plant used in traditional Chinese medicine to treat rheumatoid arthritis, lupus erythematosus, and psoriasis in China. However, its main active substance, triptolide, has toxic effects on the heart, liver, and kidneys, which limit its clinical application. Therefore, determining the mechanism of cardiotoxicity in triptolide and identifying effective early-warning biomarkers is beneficial for preventing irreversible myocardial injury. We observed changes in microRNAs and aryl hydrocarbon receptor (AhR) as potential biomarkers in triptolide-induced acute cardiotoxicity by using techniques such as polymerase chain reaction (PCR) assay. The results revealed that triptolide increased the heart/body ratio and caused myocardial fiber breakage, cardiomyocyte hypertrophy, increased cell gaps, and nuclear dissolution in treated male rats. Real-time PCR array detection revealed a more than 2-fold increase in the expression of 108 microRNA genes in the hearts of the male rats; this not only regulated the signaling pathways of ErbB, FOXO, AMPK, Hippo, HIF-1α, mTOR, and PI3K-Akt but also participated in biological processes such as cell adhesion, cell cycling, action potential, locomotory behavior, apoptosis, and DNA binding. Moreover, triptolide reduced the circulatory and cardiac levels of AhR protein as a target of these microRNAs and the messenger RNA expression of its downstream gene CYP1 A1. However, decreases in myocardial lactate dehydrogenase, creatine kinase MB, catalase, and glutathione peroxidase activity and an increase in circulating cardiac troponin I were observed only in male rats. Moreover, plasma microRNAs exhibited dynamic change. These results revealed that circulating microRNAs and AhR protein are potentially early-warning biomarkers for triptolide-induced cardiotoxicity.


Sujet(s)
Marqueurs biologiques/métabolisme , Cardiotoxicité/génétique , Diterpènes/pharmacologie , microARN/génétique , Myocytes cardiaques/effets des médicaments et des substances chimiques , Phénanthrènes/pharmacologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Apoptose/génétique , Cardiotoxicité/métabolisme , Médicaments issus de plantes chinoises/pharmacologie , Composés époxy/pharmacologie , Femelle , Mâle , Médecine traditionnelle chinoise/méthodes , Myocarde/métabolisme , Myocytes cardiaques/métabolisme , Rats , Transduction du signal/effets des médicaments et des substances chimiques , Transduction du signal/génétique , Tripterygium/composition chimique
5.
Mediators Inflamm ; 2018: 7304096, 2018.
Article de Anglais | MEDLINE | ID: mdl-30158835

RÉSUMÉ

BACKGROUND: Inflammation is one of the most important pathogeneses of thromboangiitis obliterans (TAO). The NLRP3 inflammasome plays a vital role in the body's immune response and disease development. It can be activated by numerous types of pathogens or danger signals. As the core of the inflammatory response, the NLRP3 inflammasome may provide a new target for the treatment of various inflammatory diseases. Levistilide A (LA) is a phthalide dimer isolated from umbelliferous plants. Its pharmacological effect is largely unknown. This study revealed the effects of LA on endothelial cell activation, NLRP3, IL-1ß, TNF-α, IL-32, and CCL-2, VCAM-1, MCP-1, and the spleen tyrosine kinase (Syk)--p38/JNK signaling axis and its effect on vasculitis in rats. RESULTS: LA inhibited endothelial activation and the expression of IL-1ß, TNF-α, IL-32, CCL-2, VCAM-1, and MCP-1. LA directly obstructed Syk phosphorylation and activity in a dose-dependent manner, inhibited the activity of p38 and JNK, and reduced the expression of NLRP3 in human umbilical vein endothelial cells and vascular tissue of rats with vasculitis. CONCLUSION: LA suppressed NLRP3 gene expression by blocking the Syk--p38/JNK pathway and reduced damage to the rats' limbs in the thromboangiitis obliterans model.


Sujet(s)
Composés hétérocycliques, cycle ponté/usage thérapeutique , Protéine-3 de la famille des NLR contenant un domaine pyrine/métabolisme , Syk kinase/métabolisme , Thromboangéite oblitérante/traitement médicamenteux , Thromboangéite oblitérante/métabolisme , p38 Mitogen-Activated Protein Kinases/métabolisme , Animaux , Cellules endothéliales de la veine ombilicale humaine , Humains , Système de signalisation des MAP kinases/effets des médicaments et des substances chimiques , Système de signalisation des MAP kinases/génétique , Mâle , Protéine-3 de la famille des NLR contenant un domaine pyrine/génétique , Rats , Rat Wistar
6.
PLoS One ; 12(11): e0187048, 2017.
Article de Anglais | MEDLINE | ID: mdl-29176801

RÉSUMÉ

Vaccination is a safe and effective approach to prevent deadly diseases. To increase vaccine production, we propose that a mechanical stimulation can enhance protein production. In order to prove this hypothesis, Sf9 insect cells were used to evaluate the increase in the expression of a fusion protein from hepatitis B virus (HBV S1/S2). We discovered that the ultrasound stimulation at a frequency of 1.5 MHz, intensity of 60 mW/cm2, for a duration of 10 minutes per day increased HBV S1/S2 by 27%. We further derived a model for transport through a cell membrane under the effect of ultrasound waves, tested the key assumptions of the model through a molecular dynamics simulation package, NAMD (Nanoscale Molecular Dynamics program) and utilized CHARMM force field in a steered molecular dynamics environment. The results show that ultrasound waves can increase cell permeability, which, in turn, can enhance nutrient / waste exchange thus leading to enhanced vaccine production. This finding is very meaningful in either shortening vaccine production time, or increasing the yield of proteins for use as vaccines.


Sujet(s)
Vaccins anti-hépatite B/biosynthèse , Ondes ultrasonores , 4-Chloro-7-nitro-2,1,3-benzoxadiazole/analogues et dérivés , 4-Chloro-7-nitro-2,1,3-benzoxadiazole/métabolisme , Animaux , Technique de Western , Perméabilité des membranes cellulaires , Désoxyglucose/analogues et dérivés , Désoxyglucose/métabolisme , Vaccins anti-hépatite B/immunologie , Simulation de dynamique moléculaire , Phosphatidylcholines/composition chimique , Protéines/métabolisme , Cellules Sf9 , Sonication , Thermodynamique
7.
Glia ; 64(2): 240-54, 2016 Feb.
Article de Anglais | MEDLINE | ID: mdl-26446044

RÉSUMÉ

Studies have implicated astrocytic dysfunction in Alzheimer's disease (AD). However, the role of astrocytes in the pathophysiology and treatment of the disease is poorly characterized. Here, we identified astrocytes as independent key factors involved in several Alzheimer-like phenotypes in an APP/PS1 mouse model, including amyloid pathology, altered neuronal and synaptic properties, and impaired cognition. In vitro astrocytes from APP/PS1 mice induced synaptotoxicity as well as reduced dendritic complexity and axonal branching of hippocampal neurons. These astrocytes produced high levels of soluble ß-amyloid (Aß) which could be significantly inhibited by fluoxetine (FLX) via activating serotonin 5-HT2 receptors. FLX could also protect hippocampal neurons against astrocyte-induced neuronal damage in vitro. In the same APP/PS1 mice, FLX inhibited activation of astrocytes, lowered Aß products, ameliorated neurotoxicity, and improved behavioral performance. These findings may provide a basis for the clinical application of FLX in patients, and may also lay the groundwork for exploration of other novel astrocyte-based therapies of AD.


Sujet(s)
Maladie d'Alzheimer/traitement médicamenteux , Astrocytes/effets des médicaments et des substances chimiques , Fluoxétine/pharmacologie , Neuroprotecteurs/pharmacologie , Maladie d'Alzheimer/anatomopathologie , Maladie d'Alzheimer/physiopathologie , Peptides bêta-amyloïdes/métabolisme , Précurseur de la protéine bêta-amyloïde/génétique , Précurseur de la protéine bêta-amyloïde/métabolisme , Animaux , Astrocytes/anatomopathologie , Astrocytes/physiologie , Encéphale/effets des médicaments et des substances chimiques , Encéphale/anatomopathologie , Encéphale/physiopathologie , Cellules cultivées , Modèles animaux de maladie humaine , Humains , Apprentissage du labyrinthe , Neurones/effets des médicaments et des substances chimiques , Neurones/anatomopathologie , Neurones/physiologie , Fragments peptidiques/métabolisme , Plaque amyloïde/traitement médicamenteux , Plaque amyloïde/anatomopathologie , Plaque amyloïde/physiopathologie , Préséniline-1/génétique , Préséniline-1/métabolisme , Récepteurs de la sérotonine de type 5-HT2/métabolisme
8.
J Psychiatr Res ; 65: 80-6, 2015 Jun.
Article de Anglais | MEDLINE | ID: mdl-25937503

RÉSUMÉ

BACKGROUND: Psychopathy is associated with dysfunction in regions that compose the paralimbic system, such as the orbitofrontal cortex (OFC), insular cortex (IC), temporal pole (TP), parahippocampal gyrus (PHG) and cingulate cortex (CC). However, findings of structural alterations in these regions are inconsistent in schizophrenia, and correlations between paralimbic system measures and symptomatology and cognitive function have not been investigated. METHOD: 93 patients with schizophrenia and 99 healthy controls received structural magnetic resonance imaging and clinical and cognitive assessment. We compared gray matter volume (GMV) between the two groups using voxel-based morphometry, and evaluated correlations between abnormal GMVs and clinical variables, symptomatology and cognitive function. The assessment of cognition included measures of processing speed, verbal fluency and memory. RESULTS: Patients with schizophrenia demonstrated significant GMV decreases in the paralimbic system, including bilateral OFC, IC and TP (p < 0.05, FWE corrected). GMV decreases were also observed in bilateral superior temporal gyri (STG). The GMVs in bilateral OFC, left IC, left TP and bilateral STG were positively correlated with processing speed, and the GMVs in bilateral OFC were positively correlated with memory function in all participants. In our patient group, the GMV deficits were also associated with earlier age of onset, longer duration of illness, greater number of hospitalizations and more severe positive symptoms. CONCLUSIONS: GMVs in the paralimbic system were significantly reduced in schizophrenia, and these abnormalities were correlated with clinical variables, symptomatology and cognitive function. These results suggest the paralimbic system plays an important role in the pathophysiology of schizophrenia.


Sujet(s)
Troubles de la cognition/étiologie , Substance grise/anatomopathologie , Schizophrénie/complications , Schizophrénie/anatomopathologie , Adulte , Femelle , Humains , Traitement d'image par ordinateur , Imagerie par résonance magnétique , Mâle , Tests neuropsychologiques , Échelles d'évaluation en psychiatrie , Statistiques comme sujet , Jeune adulte
9.
Curr Alzheimer Res ; 11(7): 672-80, 2014.
Article de Anglais | MEDLINE | ID: mdl-25115542

RÉSUMÉ

Alzheimer's disease (AD) is the most common neurodegenerative disorder of the central nervous system. Current approaches for AD treatment only ameliorate symptoms. Therapeutic strategies that target the pathological processes of the disease remain elusive. Fluoxetine (FLX) is one of the most widely used antidepressants for the treatment of depression and anxiety associated with AD, however, it is unknown if the drug affects the pathogenesis of the disease. We showed that FLX improved spatial memory, learning and emotional behaviors of APP/PS1 mice, a well characterized model of AD. In the same mice, FLX effectively prevented the protein loss of synaptophysin (SYP) and microtubuleassociated protein 2 (MAP2). FLX was unable to prevent plaque formation, but significantly lowered high levels of soluble ß-amyloid (Aß) in brain tissue, cerebrospinal fluid (CSF) and blood sera. FLX also effectively inhibited the phosphorylation of amyloid precursor protein (APP) at T668, which may be a possible mechanism of the reduced Aß production in APP/PS1 mouse after treatment.


Sujet(s)
Maladie d'Alzheimer/traitement médicamenteux , Maladie d'Alzheimer/physiopathologie , Précurseur de la protéine bêta-amyloïde/métabolisme , Fluoxétine/pharmacologie , Nootropiques/pharmacologie , Maladie d'Alzheimer/anatomopathologie , Maladie d'Alzheimer/psychologie , Précurseur de la protéine bêta-amyloïde/génétique , Animaux , Encéphale/effets des médicaments et des substances chimiques , Encéphale/anatomopathologie , Encéphale/physiopathologie , Modèles animaux de maladie humaine , Émotions/effets des médicaments et des substances chimiques , Émotions/physiologie , Souris transgéniques , Protéines associées aux microtubules/métabolisme , Phosphorylation/effets des médicaments et des substances chimiques , Plaque amyloïde/traitement médicamenteux , Plaque amyloïde/anatomopathologie , Plaque amyloïde/physiopathologie , Apprentissage spatial/effets des médicaments et des substances chimiques , Apprentissage spatial/physiologie , Mémoire spatiale/effets des médicaments et des substances chimiques , Mémoire spatiale/physiologie , Synaptophysine/métabolisme
10.
J Neurochem ; 131(2): 229-38, 2014 Oct.
Article de Anglais | MEDLINE | ID: mdl-24934403

RÉSUMÉ

Serotonin/norepinephrine reuptake inhibitors antidepressants exert their effects by increasing serotonin and norepinephrine in the synaptic cleft. Studies show it takes 2-3 weeks for the mood-enhancing effects, which indicate other mechanisms may underlie their treatment effects. Here, we investigated the role of white matter in treatment and pathogenesis of depression using an unpredictable chronic mild stress (UCMS) mouse model. Desvenlafaxine (DVS) was orally administrated to UCMS mice at the dose of 10 mg/kg/day 1 week before they went through a 7-week stress procedure and lasted for over 8 weeks before the mice were killed. No significant changes were found for protein markers of neurons and astrocytes in UCMS mice. However, myelin and oligodendrocyte-related proteins were significantly reduced in UCMS mice. DVS prevented the stress-induced injury to white matter and the decrease of phosphorylated 5'-AMP-activated protein kinase and 3-hydroxy-3-methyl-glutaryl-CoA reductase protein expression. DVS increased open arm entries in an elevated plus-maze test, sucrose consumption in the sucrose preference test and decreased immobility in tail suspension and forced swimming tests. These findings suggest that stress induces depression-like behaviors and white matter deficits in UCMS mice. DVS may ameliorate the oligodendrocyte dysfunction by affecting cholesterol synthesis, alleviating the depression-like phenotypes in these mice. We examined the possible role of oligodendrocyte and myelin in the pathological changes of depression with an unpredictable chronic mild stress (UCMS) mouse model. Oligodendrocyte-related proteins in the mouse brain were specifically changed during the stress period. The depressive-like behaviors and oligodendrocyte deficits could be prevented by the administration of desvenlafaxine. Oligodendrocyte and myelin may be an essential target of desvenlafaxine for the treatment of depression.


Sujet(s)
Cholestérol/biosynthèse , Cyclohexanols/usage thérapeutique , Dépression/traitement médicamenteux , Dépression/enzymologie , Modèles animaux de maladie humaine , Substance blanche/enzymologie , Animaux , Antidépresseurs/pharmacologie , Antidépresseurs/usage thérapeutique , Cyclohexanols/pharmacologie , Dépression/anatomopathologie , Succinate de dèsvenlafaxine , Femelle , Souris , Souris de lignée C57BL , Phosphorylation/effets des médicaments et des substances chimiques , Phosphorylation/physiologie , Répartition aléatoire , Substance blanche/effets des médicaments et des substances chimiques , Substance blanche/anatomopathologie
11.
Neuroreport ; 25(11): 870-874, 2014 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-24911389

RÉSUMÉ

Previous studies have suggested that the cerebral microglia activation was associated with Aß plaques, whereas quetiapine, an atypical antipsychotic drug, decreased Aß levels in Alzheimer's disease (AD) mice. The aim of the present study was to evaluate the effects of quetiapine on microglial activation in an amyloid precursor protein/presenilin-1 double transgenic mouse model of AD. Nontransgenic and transgenic mice were treated with quetiapine (0 or 5 mg/kg/day) in drinking water from the age of 2 months. After 10 months of continuous quetiapine administration, the mice were killed, and hippocampal microglial activation was measured by immunohistochemistry staining of CD11b-positive cells. The results showed that quetiapine significantly decreased the number of CD11b-positive cells and ß-amyloid peptide levels in the hippocampus of transgenic mice. These suggest that quetiapine can attenuate microglia activation in an amyloid precursor protein/presenilin-1 transgenic mouse model of AD, and this may be related to quetiapine's beneficial effects in AD treatment.

12.
J Neurochem ; 130(6): 780-9, 2014 Sep.
Article de Anglais | MEDLINE | ID: mdl-24862291

RÉSUMÉ

Previous studies have demonstrated that quetiapine (QTP) may have neuroprotective properties; however, the underlying mechanisms have not been fully elucidated. In this study, we identified a novel mechanism by which QTP increased the synthesis of ATP in astrocytes and protected GABAergic neurons from aging-induced death. In 12-month-old mice, QTP significantly improved cell number of GABAegic neurons in the cortex and ameliorated anxiety-like behaviors compared to control group. Complimentary in vitro studies showed that QTP had no direct effect on the survival of aging GABAergic neurons in culture. Astrocyte-conditioned medium (ACM) pretreated with QTP (ACMQTP) for 24 h effectively protected GABAergic neurons against aging-induced spontaneous cell death. It was also found that QTP boosted the synthesis of ATP from cultured astrocytes after 24 h of treatment, which might be responsible for the protective effects on neurons. Consistent with the above findings, a Rhodamine 123 test showed that ACMQTP, not QTP itself, was able to prevent the decrease in mitochondrial membrane potential in the aging neurons. For the first time, our study has provided evidence that astrocytes may be the conduit through which QTP is able to exert its neuroprotective effects on GABAergic neurons. The neuroprotective properties of quetiapine (QTP) have not been fully understood. Here, we identify a novel mechanism by which QTP increases the synthesis of ATP in astrocytes and protects GABAergic neurons from aging-induced death in a primary cell culture model. In 12-month-old mice, QTP significantly improves cell number of GABAegic neurons and ameliorates anxiety-like behaviors. Our study indicates that astrocytes may be the conduit through which QTP exerts its neuroprotective effects on GABAergic neurons.


Sujet(s)
Vieillissement/psychologie , Neuroleptiques/pharmacologie , Anxiété/psychologie , Astrocytes/physiologie , Comportement animal/effets des médicaments et des substances chimiques , Dibenzothiazépines/pharmacologie , Neurones/effets des médicaments et des substances chimiques , Agents protecteurs , Acide gamma-amino-butyrique/physiologie , Adénosine triphosphate/biosynthèse , Adénosine triphosphate/métabolisme , Animaux , Numération cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Milieux de culture conditionnés , Obscurité , Comportement d'exploration/effets des médicaments et des substances chimiques , Femelle , Immunohistochimie , Lumière , Souris , Souris de lignée C57BL , Activité motrice/effets des médicaments et des substances chimiques , Culture de cellules primaires , Fumarate de quétiapine , Régulation positive/effets des médicaments et des substances chimiques
13.
Neuroreport ; 25(9): 647-50, 2014 Jun 18.
Article de Anglais | MEDLINE | ID: mdl-24642954

RÉSUMÉ

Quetiapine, an atypical antipsychotic drug, may have beneficial effects in Alzheimer's disease (AD), and the effect of quetiapine on object recognition memory in AD has never been measured. The aim of the present study was to evaluate the effects of quetiapine on object recognition memory and on oxidative stress that could be involved in the AD pathogenesis in an amyloid precursor protein/presenilin-1 double transgenic mouse model of AD. Nontransgenic and transgenic mice were treated with quetiapine (0 or 5 mg/kg/day) in drinking water from the age of 2 months. After 10 months of continuous quetiapine administration, object recognition memory impairment and the increased hippocampal protein expression of nitrotyrosine, a protein marker of oxidative stress, were attenuated in the AD mice. These results suggest that quetiapine can attenuate object recognition memory impairment and brain oxidative stress in an amyloid precursor protein/presenilin-1 transgenic mouse model of AD and indicate that the antioxidative effect of early quetiapine intervention may be associated with the beneficial effect of quetiapine on memory in AD.


Sujet(s)
Maladie d'Alzheimer/traitement médicamenteux , Neuroleptiques/pharmacologie , Dibenzothiazépines/pharmacologie , Hippocampe/effets des médicaments et des substances chimiques , Troubles de la mémoire/traitement médicamenteux , Stress oxydatif/effets des médicaments et des substances chimiques , Animaux , Neuroleptiques/administration et posologie , Comportement animal/effets des médicaments et des substances chimiques , Dibenzothiazépines/administration et posologie , Modèles animaux de maladie humaine , Femelle , Hippocampe/physiopathologie , Souris , Souris transgéniques , Fumarate de quétiapine , /effets des médicaments et des substances chimiques
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