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1.
J Clin Invest ; 134(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38060311

RESUMO

Platelets from patients with myeloproliferative neoplasms (MPNs) exhibit a hyperreactive phenotype. Here, we found elevated P-selectin exposure and platelet-leukocyte aggregates indicating activation of platelets from essential thrombocythemia (ET) patients. Single-cell RNA-seq analysis of primary samples revealed significant enrichment of transcripts related to platelet activation, mTOR, and oxidative phosphorylation in ET patient platelets. These observations were validated via proteomic profiling. Platelet metabolomics revealed distinct metabolic phenotypes consisting of elevated ATP generation accompanied by increases in the levels of multiple intermediates of the tricarboxylic acid cycle, but lower α-ketoglutarate (α-KG) in MPN patients. Inhibition of PI3K/AKT/mTOR signaling significantly reduced metabolic responses and hyperreactivity in MPN patient platelets, while α-KG supplementation markedly reduced oxygen consumption and ATP generation. Ex vivo incubation of platelets from both MPN patients and Jak2 V617F-knockin mice with α-KG supplementation significantly reduced platelet activation responses. Oral α-KG supplementation of Jak2 V617F mice decreased splenomegaly and reduced hematocrit, monocyte, and platelet counts. Finally, α-KG treatment significantly decreased proinflammatory cytokine secretion from MPN CD14+ monocytes. Our results reveal a previously unrecognized metabolic disorder in conjunction with aberrant PI3K/AKT/mTOR signaling that contributes to platelet hyperreactivity in MPN patients.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Trombocitemia Essencial , Humanos , Camundongos , Animais , Multiômica , Fosfatidilinositol 3-Quinases/genética , Proteômica , Proteínas Proto-Oncogênicas c-akt/genética , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Trombocitemia Essencial/genética , Inflamação , Serina-Treonina Quinases TOR/genética , Trifosfato de Adenosina , Janus Quinase 2/genética , Mutação
2.
Chem Res Toxicol ; 35(12): 2252-2259, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36484463

RESUMO

Perfluorooctanoic acid is a manufactured material extensively utilized in industrial and consumer products. As a persistent organic pollutant, perfluorooctanoic acid has raised increasing public health concerns recently. Although perfluorooctanoic acid is known to induce lipid accumulation in the liver, the impact of perfluorooctanoic acid on different lipid classes has not been fully evaluated. In this study, we performed untargeted lipidomics analysis to investigate the impact of perfluorooctanoic acid on the lipid homeostasis in C57BL/6 male mice. Perfluorooctanoic acid disturbed the lipid profiles in serum and liver, with a variety of lipid classes significantly altered. Greater impacts were observed in the liver lipidome than the serum lipidome. In particular, some lipid clusters in the liver were altered by both high- and low-dose perfluorooctanoic acid exposure, including the increase of unsaturated triglycerides and the decrease of sphingomyelins, saturated phosphatidylcholines, saturated lysophosphatidylcholines, and phospholipid ethers. In parallel with an increase in the liver, a decrease of saturated phosphatidylcholines was found in the serum of high-dose perfluorooctanoic acid-treated mice. The findings from this study are helpful to improve the understanding of perfluorooctanoic acid-induced dysregulation of lipid metabolism and perfluorooctanoic acid-associated health effects in liver.


Assuntos
Caprilatos , Lipidômica , Masculino , Camundongos , Animais , Camundongos Endogâmicos C57BL , Caprilatos/toxicidade , Fígado/metabolismo , Metabolismo dos Lipídeos , Fosfatidilcolinas/metabolismo , Fosfatidilcolinas/farmacologia
3.
Ying Yong Sheng Tai Xue Bao ; 33(4): 981-987, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543050

RESUMO

Potassium (K) is the second most abundant nutrient in plant leaves after nitrogen (N) and the most abundant cation in plant cells. It plays an important role in plant growth regulation, homeostasis maintenance, and stress response. Previous studies on the effects of N input on plant nutrient status mainly focus on N and phosphorus (P), but less on K and its stoichiometry. We examined the effects of N input and mowing on K content and N:K at both plant functional group and community levels. We analyzed the relative contribution of changes in functional groups and community composition to changes of community level nutrition status. The results showed that N input increased N content of each plant functional group and increased K content of rhizomatous grasses and legumes. Mowing reduced N content of rhizomatous grasses and bunchgrass, but did not affect K content and N:K of all functional groups. Nitrogen input significantly increased plant N and K contents at the community level, while mowing significantly increased plant N content. Both N input and mowing did not affect plant N:K at functional group and community levels. The contribution of nutritional changes in plant functional groups to the variation at the community level was greater than that of changes in community composition. For all the three examined nutritional traits, the contribution of nutrients at functional group level and that of community composition showed negative covariation. Our results indicated that plant N:K had high homeostasis in meadow steppe and that plants could regulate N and K balance, which was of great significance for maintaining N:K stoichiometry under the background of increasing N deposition.


Assuntos
Pradaria , Nitrogênio , China , Ecossistema , Nitrogênio/análise , Fósforo , Plantas , Poaceae , Potássio , Solo
4.
Chin J Integr Med ; 27(7): 527-533, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31903531

RESUMO

OBJECTIVE: To investigate the protective effects of Shexiang Tongxin Dropping Pill (, STDP) following sodium laurate-induced coronary microembolization (CME) in rats. METHODS: Forty rats were divided into 4 groups: the control (sham) group, CME group, low-dose STDP pretreatment group (20 mg·kg-1·d-1), and high-dose STDP pretreatment group (40 mg·kg-1·d-1). The rats were intragastric administrated with STDP 2 weeks before operation. Moreover, the histopathological alterations were observed using optical microscopy and transmission electron microscopy. Antioxidant biomarkers were analyzed by enzyme-linked immunosorbent assay. Mitochondrial functions including the mitochondrial permeability transition pore (mPTP) mtDNA copy number were determined and proteins of AKT/GSK3ß were analyzed by Western blot. RESULTS: The rats in the CME group showed a significant increase in the fibrinogen-like protein 2 expression level and mitochondrial dysfunction and a decrease in the expression level of antioxidant biomarkers (superoxide dismutase and catalase, P<0.01 for all). In contrast, the rats in the low- and high-dose STDP pretreatment groups showed a significant decrease in coronary microthrombi (P<0.05); moreover, STDP restored the antioxidant-related protein activities and mitochondrial function, inhibited mPTP opening, decreased AKT-Ser473 phosphorylation, and increased GSK3ß-Ser9 phosphorylation (P<0.05 or P<0.01). CONCLUSION: STDP may be useful for treatment of CME, possibly via regulation of mPTP opening and AKT/GSK3ß phosphorylation.


Assuntos
Poro de Transição de Permeabilidade Mitocondrial , Proteínas Proto-Oncogênicas c-akt , Animais , Medicamentos de Ervas Chinesas , Quinase 3 da Glicogênio Sintase , Proteínas de Transporte da Membrana Mitocondrial , Fosforilação , Ratos
5.
Zhongguo Zhong Yao Za Zhi ; 45(4): 829-837, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237483

RESUMO

The flower color of Dendrobium catenatum(D. officinale) tends to fade during storage. In order to clarify the influence of storage conditions on the pigment components in flowers, two conditions were applied:temperature and illumination. The contents of pigments in the D. catenatum flower were determined by UV-Vis spectrophotometry and HPLC, and the changes of them during storage were analyzed. The results showed that illumination and temperature had an effect on the pigments of D. catenatum flower during sto-rage. Illumination significantly promoted the degradation of pigments. The contents of total chlorophyll, carotenoids and anthocyanins in the light samples were significantly lower than those in the dark. The total chlorophyll, carotenoids and anthocyanins in the light samples were decreased by 46.5%, 63.4%, and 69.2% respectively. Illumination had a greater effect on fat-soluble pigments than water-soluble pigments. Among the three temperature treatments, the contents of chlorophyll, carotenoid and anthocyanin were as follows:-20 ℃>4 ℃>room temperature, it is indicated that-20 ℃ was the best temperature to maintain the stability of pigment composition. The contents of chlorophyll a, chlorophyll b, ß-carotene, lutein and zeaxanthin in the light samples decreased by 34.8%, 69.0%, 72.5%, 61.6%, 36.1%, respectively. After storage for 5 months, the contents of chlorophyll, carotenoid and anthocyanin constituent at-20 ℃ was significantly higher than those at 4 ℃ and room temperature. The results show that light avoiding and low-temperature can effectively slow down the degradation of pigment components. Therefore, it is suggested that D. catenatum flower should be stored in light avoiding and low-temperature conditions in actual production and processing, which can prolong the usable time.


Assuntos
Dendrobium/química , Armazenamento de Medicamentos , Flores/química , Pigmentos Biológicos/análise , Antocianinas/análise , Carotenoides/análise , Clorofila/análise , Cromatografia Líquida de Alta Pressão , Luz , Plantas Medicinais/química , Espectrofotometria , Temperatura
6.
MAbs ; 11(6): 1149-1161, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31161871

RESUMO

An anti-CD30 antibody-drug conjugate incorporating the antimitotic agent DM1 and a stable SMCC linker, anti-CD30-MCC-DM1, was generated as a new antitumor drug candidate for CD30-positive hematological malignancies. Here, the in vitro and in vivo pharmacologic activities of anti-CD30-MCC-DM1 (also known as F0002-ADC) were evaluated and compared with ADCETRIS (brentuximab vedotin). Pharmacokinetics (PK) and the safety profiles in cynomolgus monkeys were assessed. Anti-CD30-MCC-DM1 was effective in in vitro cell death assays using CD30-positive lymphoma cell lines. We studied the properties of anti-CD30-MCC-DM1, including binding, internalization, drug release and actions. Unlike ADCETRIS, anti-CD30-MCC-DM1 did not cause a bystander effect in this study. In vivo, anti-CD30-MCC-DM1 was found to be capable of inducing tumor regression in subcutaneous inoculation of Karpas 299 (anaplastic large cell lymphoma), HH (cutaneous T-cell lymphoma) and L428 (Hodgkin's disease) cell models. The half-lives of 4 mg/kg and 12 mg/kg anti-CD30-MCC-DM1 were about 5 days in cynomolgus monkeys, and the tolerated dose was 30 mg/kg in non-human primates, supporting the tolerance of anti-CD30-MCC-DM1 in humans. These results suggest that anti-CD30-MCC-DM1 presents efficacy, safety and PK profiles that support its use as a valuable treatment for CD30-positive hematological malignancies.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Hematológicas , Imunoconjugados/farmacologia , Antígeno Ki-1/imunologia , Linfoma Anaplásico de Células Grandes , Animais , Antineoplásicos/imunologia , Brentuximab Vedotin/imunologia , Brentuximab Vedotin/farmacologia , Avaliação Pré-Clínica de Medicamentos , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/patologia , Humanos , Imunoconjugados/imunologia , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/imunologia , Linfoma Anaplásico de Células Grandes/patologia , Macaca fascicularis , Camundongos , Camundongos SCID
7.
Dig Dis Sci ; 64(7): 1878-1892, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31076986

RESUMO

BACKGROUND: Alcohol-related liver disease is one of the most prevalent chronic liver diseases worldwide. Mechanisms involved in the pathogenesis of alcohol-related liver disease are not well understood. Oxylipins play a crucial role in numerous biological processes and pathological conditions. Nevertheless, oxylipins are not well studied in alcohol-related liver disease. AIMS: (1) To characterize the patterns of bioactive ω-3 and ω-6 polyunsaturated fatty acid metabolites in alcohol use disorder and alcoholic hepatitis patients and (2) to identify associations of serum oxylipins with clinical parameters in patients with alcohol-related liver disease. METHODS: We performed a comprehensive liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis of serum and fecal oxylipins derived from ω-6 arachidonic acid, ω-3 eicosapentaenoic acid, and docosahexaenoic acid in a patient cohort with alcohol-related liver disease. RESULTS: Our results show profound alterations in the serum oxylipin profile of patients with alcohol use disorder and alcoholic hepatitis compared to nonalcoholic controls. Spearman correlation of the oxylipins with clinical parameters shows a link between different serum oxylipins and intestinal permeability, aspartate aminotransferase, bilirubin, albumin, international normalized ratio, platelet count, steatosis, fibrosis and model for end-stage liver disease score. Especially, higher level of serum 20-HETE was significantly associated with decreased albumin, increased hepatic steatosis, polymorphonuclear infiltration, and 90-day mortality. CONCLUSIONS: Patients with alcohol-related liver disease have different oxylipin profiles. Future studies are required to confirm oxylipins as disease biomarker or to connect oxylipins to disease pathogenesis.


Assuntos
Alcoolismo/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Fezes/química , Hepatite Alcoólica/sangue , Oxilipinas/sangue , Adulto , Idoso , Alcoolismo/diagnóstico , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Feminino , Hepatite Alcoólica/diagnóstico , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
8.
Molecules ; 24(3)2019 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-30691236

RESUMO

: Inflammatory bowel disease (IBD) has stimulated much interest due to its surging incidences and health impacts in the U.S. and worldwide. However, the exact cause of IBD remains incompletely understood, and biomarker is lacking towards early diagnostics and effective therapy assessment. To tackle these, the emerging high-resolution mass spectrometry (HRMS)-based metabolomics shows promise. Here, we conducted a pilot untargeted LC/MS metabolomic profiling in Crohn's disease, for which serum samples of both active and inactive cases were collected, extracted, and profiled by a state-of-the-art compound identification workflow. Results show a distinct metabolic profile of Crohn's from control, with most metabolites downregulated. The identified compounds are structurally diverse, pointing to important pathway perturbations ranging from energy metabolism (e.g., ß-oxidation of fatty acids) to signaling cascades of lipids (e.g., DHA) and amino acid (e.g., L-tryptophan). Importantly, an integral role of gut microbiota in the pathogenesis of Crohn's disease is highlighted. Xenobiotics and their biotransformants were widely detected, calling for massive exposomic profiling for future cohort studies as such. This study endorses the analytical capacity of untargeted metabolomics for biomarker development, cohort stratification, and mechanistic interpretation; the findings might be valuable for advancing biomarker research and etiologic inquiry in IBD.


Assuntos
Doença de Crohn/metabolismo , Metabolismo Energético , Metaboloma , Metabolômica , Transdução de Sinais , Aminoácidos/metabolismo , Biomarcadores , Doença de Crohn/sangue , Ácidos Graxos/metabolismo , Humanos , Metabolismo dos Lipídeos , Oxirredução
9.
ACS Omega ; 3(9): 10927-10937, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30288460

RESUMO

Gut microbiome plays an essential role in host health through host-gut microbiota metabolic interactions. Desirable modulation of beneficial gut bacteria, such as Akkermansia muciniphila, can confer health benefits by altering microbiome-related metabolic profiles. The purpose of this study is to examine the effects of a black raspberry-rich diet to reshape the gut microbiome by selectively boosting A. muciniphila population in C57BL/6J mice. Remarkable changes of the mouse gut microbiome were revealed at both compositional and functional levels with an expected increase of A. muciniphila in concert with a profound impact on multiple gut microbiome-related functions, including vitamin biosynthesis, aromatic amino acid metabolism, carbohydrate metabolism, and oxidative stress. These functional alterations in the gut microbiome by an easily accessed freeze-dried black raspberry-supplemented diet may provide novel insights on the improvement of human health via gut microbiome modulation.

10.
PeerJ ; 4: e2554, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27781160

RESUMO

Climate change will significantly affect plant distribution as well as the quality of medicinal plants. Although numerous studies have analyzed the effect of climate change on future habitats of plants through species distribution models (SDMs), few of them have incorporated the change of effective content of medicinal plants. Schisandra sphenanthera Rehd. et Wils. is an endangered traditional Chinese medical plant which is mainly located in the Qinling Mountains. Combining fuzzy theory and a maximum entropy model, we obtained current spatial distribution of quality assessment for S. spenanthera. Moreover, the future quality and distribution of S. spenanthera were also projected for the periods 2020s, 2050s and 2080s under three different climate change scenarios (SRES-A1B, SRES-A2 and SRES-B1 emission scenarios) described in the Special Report on Emissions Scenarios (SRES) of IPCC (Intergovernmental Panel on Climate Change). The results showed that the moderately suitable habitat of S. sphenanthera under all climate change scenarios remained relatively stable in the study area. The highly suitable habitat of S. sphenanthera would gradually decrease in the future and a higher decline rate of the highly suitable habitat area would occur under climate change scenarios SRES-A1B and SRES-A2. The result suggested that in the study area, there would be no more highly suitable habitat areas for S. sphenanthera when the annual mean temperature exceeds 20 °C or its annual precipitation exceeds 1,200 mm. Our results will be influential in the future ecological conservation and management of S. sphenanthera and can be taken as a reference for habitat suitability assessment research for other medicinal plants.

11.
Appl Biochem Biotechnol ; 180(5): 900-916, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27246002

RESUMO

An arabinanase gene was cloned by overlap-PCR from Penicillium sp. Y702 and expressed in Pichia pastoris. The recombinant enzyme was named AbnC702 with 20 U/mg of endo-arabinanase activity toward linear α-1,5-L-arabinan. The optimal pH and temperature of AbnC702 were 5.0 and 50 °C, respectively. The recombinant AbnC702 was highly stable at pH 5.0-7.0 and 50 °C. It could retain about 72.3 % of maximum specific activity at pH 5.0 after incubation for 2.5 h, which indicated AbnC702 was an acid-adapted enzyme. The K m and V max values were 24.8 ± 4.7 mg/ml and 88.5 ± 5.6 U/mg, respectively. A three-dimensional structure of AbnC702 was made by homology modeling, and the counting of acidic/basic amino residues within the region of 10 Å around the active site, as well the hydrogen bonds within the area of 5 Å around the active site, might theoretically interpret the acid adaptability of AbnC702. Analysis of hydrolysis products by thin layer chromatography (TLC) combined with high-performance liquid chromatography (HPLC) verified that the recombinant AbnC702 was an endo-1,5-α-L-arabinanase, which yielded arabinobiose and arabinotriose as major products. AbnC702 was applied in pectin extraction from apple pomace with synergistic action of α-L-arabinofuranosidase.


Assuntos
Ácidos/farmacologia , Glicosídeo Hidrolases/metabolismo , Pectinas/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/isolamento & purificação , Concentração de Íons de Hidrogênio , Hidrólise , Malus/química , Modelos Moleculares , Alinhamento de Sequência , Especificidade por Substrato/efeitos dos fármacos
12.
Brain Res ; 1392: 8-15, 2011 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-21458428

RESUMO

We investigated the role of connexin 43 (Cx43) hemichannels in the release of glutamate by astrocytes after hypertonic stimulus. Mechanical, osmotic and oxidative stress, and changes in the extracellular or intracellular Ca(2+) levels induce connexin hemichannels located in the plasma membrane to open and release small ions and molecules with signaling potential such as glutamate, ATP, etc. In our past studies, we primarily found that acute hypertonic stimulus induced the release of glutamate. Since glutamate release was involved with several routes, we studied its release routes by astrocytes incubated in a hypertonic media for various periods. The glutamate release was increased after hypertonic stimulus. Glutamate release in hypertonic stimulus was inhibited by gap junction or Cx43 hemichannel blockers, but not by antagonists of purinergic receptor (P2XnR), glutamate transport inhibitors, intracellular Ca(2+) blockers, and pannexin 1(Panx1) hemichannel. The results suggest that glutamate release by the Cx43 hemichannels is likely to feature in the response of cultured astrocytes to hypertonic stimulus.


Assuntos
Astrócitos/efeitos dos fármacos , Conexina 43/metabolismo , Ácido Glutâmico/metabolismo , Soluções Hipertônicas/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Ácido Aspártico/farmacologia , Astrócitos/metabolismo , Células Cultivadas , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Inibidores Enzimáticos/farmacologia , Líquido Extracelular/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Hipotálamo/citologia , Osmose/fisiologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
J Biotechnol ; 139(2): 169-75, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19007827

RESUMO

A lipase-producing bacterium K107 was isolated from soil samples of China and identified to be a strain of Proteus sp. With genome-walking method, the open reading frame of lipase gene lipK107, encoding 287 amino acids, was cloned and expressed in a heterologous host, Escherichia coli BL21 (DE3). The recombinant lipase was purified and characterized, and the optimum pH of the purified LipK107 was 9, at 35 degrees C. The recombinant E. coli expressing lipK107 was applied in biodiesel production in the form of whole-cell biocatalyst. Activity of the biocatalyst increased significantly when cells were permeabilized with 0.3% (w/v) cetyl-trimethylammoniumbromide (CTAB). This transesterification was carried out efficiently in a mixture containing 5M equivalents of methanol to the oil and 100% water by weight of the substrate. It was the first time to use E. coli whole-cell biocatalyst expressing lipase in biodiesel production, and the biodiesel reached a yield of nearly 100% after 12h reaction at the optimal temperature of 15 degrees C, which was the lowest temperature among all the known catalyst in biodiesel production.


Assuntos
Reatores Biológicos , Fontes Geradoras de Energia , Escherichia coli/genética , Lipase/genética , Lipase/metabolismo , Proteus/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biocatálise , Cetrimônio , Compostos de Cetrimônio/química , China , Clonagem Molecular , Escherichia coli/metabolismo , Esterificação , Concentração de Íons de Hidrogênio , Lipase/química , Metanol/metabolismo , Dados de Sequência Molecular , Óleos de Plantas/metabolismo , Proteus/genética , Proteus/isolamento & purificação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Microbiologia do Solo , Temperatura , Água/metabolismo
14.
Neurosci Bull ; 24(6): 359-66, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19037321

RESUMO

OBJECTIVE: To investigate whether hypertonic saline (HS) can induce the synthesis and release of glutamate in cultured hypothalamic astrocytes or C6 cell line. METHODS: Astrocytes were isolated, cultured, purified and identified from the hypothalamus of newborn rat (1 day). The astrocytes were randomly divided into five groups: isotonic (IS) and HS groups, astrocytes were incubated by IS and HS (320 mosM NaCl) medium, respectively, for 1, 3, 5, 10 or 15 min; carbenoxolone (CBX)+IS and CBX+HS groups, astrocytes were pre-treated with CBX (100 mmol/L) for 1 h at 37 degrees C in a 5% CO(2) / 95% atmosphere, then removed to IS and HS medium, respectively, for 1, 3, 5, 10 or 15 min; Ca(2+)+HS group, astrocytes were pre-incubated with Ca Ca(2+) (1,000 micromol/L) for 1 h at 37 degrees C in a 5% CO(2) / 95% atmosphere, followed by a wash with isotonic FBS/DMEM, and then removed to hypertonic saline for 1, 3, 5, 10 or 15 min. The media of five groups were collected to analyze the medium glutamate concentration with high performance liquid chromatography. The astrocytes were fixed and double immunofluorescent stained with anti-glial fibrillary acidic protein (GFAP) and anti-glutamate. The C6 cells were divided into four groups: IS, HS, CBX+IS and CBX+HS groups, and used for quantitative measurement of glutamate in cells by flow cytometry (FCM). RESULTS: (1) Anti-GFAP immunofluorescent signal revealed no significant difference among various time points in each group, or among the five groups. (2) The anti-glutamate immunofluorescent signal was increased in HS group and peaked at 5 min, and decreased and returned to the level of IS group at 15 min (P < 0.01 vs the 5 min of HS group). In CBX+HS group, the glutamate intensity was higher than that in CBX+IS and HS groups. (3) The medium glutamate concentration had no change after treatment with HS for 1 and 3 min, while increased markedly after treatment for 5 min to 15 min (P< 0.01 vs 1 min and 3 min). On the contrary, the medium glutamate concentrations in the CBX+HS or Ca(2+)+HS group were significant lower than that in the HS group (P < 0.01). (4) FCM showed HS and CBX+HS induced glutamate increase in C6 cells. CONCLUSION: HS induced cultured rat hypothalamic astrocytes or C6 cells to synthesize and release glutamate; CBX could block glutamate release, but could not disrupt glutamate synthesis.


Assuntos
Astrócitos/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Solução Salina Hipertônica/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Cálcio/farmacologia , Carbenoxolona/farmacologia , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Hipotálamo/citologia , Ratos , Fatores de Tempo
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