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1.
Neurochem Res ; 49(7): 1665-1676, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38411782

RESUMO

Cerebral ischemic preconditioning (CIP) has been shown to improve brain ischemic tolerance against subsequent lethal ischemia. Reactive astrocytes play important roles in cerebral ischemia-reperfusion. Recent studies have shown that reactive astrocytes can be polarized into neurotoxic A1 phenotype (C3d) and neuroprotective A2 phenotype (S100A10). However, their role in CIP remains unclear. Here, we focused on the role of N-myc downstream-regulated gene 2 (NDRG2) in regulating the transformation of A1/A2 astrocytes and promoting to brain ischemic tolerance induced by CIP. A Sprague Dawley rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) was used. Rats were divided into the following six groups: (1) sham group; (2) CIP group: left middle cerebral artery was blocked for 10 min; (3) MCAO/R group: left middle cerebral artery was blocked for 90 min; (4) CIP + MCAO/R group: CIP was performed 72 h before MCAO/R; (5) AAV-NDRG2 + CIP + MCAO/R group: adeno-associated virus (AAV) carrying NDRG2 was administered 14 days before CIP + MCAO/R; (6) AAV-Ctrl + CIP + MCAO/R group: empty control group. The rats were subjected to neurological evaluation 24 h after the above treatments, and then were sacrificed for 2, 3, 5-triphenyltetraolium chloride staining, thionin staining, immunofluorescence and western blot analysis. In CIP + MCAO/R group, the neurological deficit scores decreased, infarct volume reduced, and neuronal density increased compared with MCAO/R group. Notably, CIP significantly increased S100A10 expression and the number of S100A10+/GFAP+ cells, and also increased NDRG2 expression. MCAO/R significantly decreased S100A10 expression and the number of S100A10+/GFAP+ cells yet increased C3d expression and the number of C3d+/GFAP+ cells and NDRG2 expression, and these trends were reversed by CIP + MCAO/R. Furthermore, over-expression of NDRG2 before CIP + MCAO/R, the C3d expression and the number of C3d+/GFAP+ cells increased, while S100A10 expression and the number of S100A10+/GFAP+ cells decreased. Meanwhile, over-expression of NDRG2 blocked the CIP-induced brain ischemic tolerance. Taken together, these results suggest that CIP exerts neuroprotective effects against ischemic injury by suppressing A1 astrocyte polarization and promoting A2 astrocyte polarization via inhibiting NDRG2 expression.


Assuntos
Astrócitos , Isquemia Encefálica , Infarto da Artéria Cerebral Média , Precondicionamento Isquêmico , Ratos Sprague-Dawley , Animais , Precondicionamento Isquêmico/métodos , Masculino , Astrócitos/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Isquemia Encefálica/metabolismo , Ratos , Proteínas do Tecido Nervoso
2.
Br J Nutr ; 131(2): 185-192, 2024 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-37589127

RESUMO

The effects of monolaurin (ML) on the health of piglets infected with porcine epidemic diarrhoea virus (PEDV) have not been fully understood. This study aimed to investigate its role in blood biochemical profile, intestinal barrier function, antioxidant function and the expression of antiviral genes in piglets infected with PEDV. Thirty-two piglets were randomly divided into four groups: control group, ML group, PEDV group and ML + PEDV group. Piglets were orally administrated with ML at a dose of 100 mg/kg·BW for 7 d before PEDV infection. Results showed that PEDV infection significantly decreased D-xylose content and increased intestinal fatty acid-binding protein content, indicating that PEDV infection destroyed intestinal barrier and absorption function. While it could be repaired by ML administration. Moreover, ML administration significantly decreased plasma blood urea nitrogen and total protein content upon PEDV infection. These results suggested ML may increase protein utilisation efficiency. ML administration significantly decreased the number of large unstained cells and Hb and increased the number of leucocytes and eosinophils in the blood of PEDV-infected piglets, indicating ML could improve the immune defense function of the body. In the presence of PEDV infection, ML administration significantly increased superoxide dismutase and catalase activities in blood and colon, respectively, indicating ML could improve antioxidant capacity. Besides, ML administration reversed the expression of ISG15, IFIT3 and IL-29 throughout the small intestine and Mx1 in jejunum and ileum, indicating the body was in recovery from PEDV infection. This study suggests that ML could be used as a kind of feed additive to promote swine health upon PEDV infection.


Assuntos
Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Suínos , Antioxidantes , Intestinos , Intestino Delgado
3.
Waste Manag Res ; : 734242X231219629, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297502

RESUMO

Implementation of municipal solid waste (MSW) source segregation leads to a more convenient recycle of combustible MSW components. Textiles, plastics and papers are commonly available combustible components in MSW. Their shredding is conducive to resources recovery. But these components usually have high tensile strengths and are difficult to shred. To understand their mechanical strength changes in their early pyrolysis stage will help to address this problem. In this study, a universal electronic testing machine was used to determine the breaking strengths of the materials including cotton towel, polyethylene glycol terephthalate (PET), ivory board (IB), kraft paper (KP) and wool scarf in the temperature range of 30-250°C under N2 atmosphere, and the mechanisms of their strength changes were explored. The reaction force field molecular dynamics (ReaxFF-MD) simulation was used to explain the decomposition behaviours of different sugar groups of hemicellulose in cotton and paper and the change of van der Waals energy of wool during their early pyrolysis stages. The results showed that breaking strengths of all the combustible MSW components reduced as the temperature increased. The breaking strength of PET was found to have the highest descent rate with increasing temperature, then the descent rates of wool and cotton came as the second and third, respectively. Compared with cotton, the breaking strengths of KP and IB decreased more slowly. As the temperature increased, the breaking strength of cotton reduced mainly due to the decomposition of the glucuronic acid in hemicellulose, and the reduction was characterized by CO2 release. The breaking strength reduction of PET was caused by its molecular chain being relaxed. The breaking strength reduction of wool was firstly caused by the decrease in the van der Waals energy between its molecules, and then caused by molecular chain breaking. In addition, in order to understand the influence of material size on the breaking strength change during thermal treatment, the breaking strengths of cotton yarn bundles were correlated with their yarn number and temperature. This study lays the foundation for understanding changes in mechanical strengths of combustible MSW components during their early pyrolysis stage.

4.
Cell Mol Neurobiol ; 43(3): 1355-1367, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35900650

RESUMO

Cerebral ischemic preconditioning (CIP)-induced brain ischemic tolerance protects neurons from subsequent lethal ischemic insult. However, the specific mechanisms underlying CIP remain unclear. In the present study, we explored the hypothesis that peroxisome proliferator-activated receptor gamma (PPARγ) participates in the upregulation of Klotho during the induction of brain ischemic tolerance by CIP. First we investigated the expression of Klotho during the brain ischemic tolerance induced by CIP. Lethal ischemia significantly decreased Klotho expression from 6 h to 7 days, while CIP significantly increased Klotho expression from 12 h to 7 days in the hippocampal CA1 region. Inhibition of Klotho expression by its shRNA blocked the neuroprotection induced by CIP. These results indicate that Klotho participates in brain ischemic tolerance by CIP. Furthermore, we tested the role of PPARγ in regulating Klotho expression after CIP. CIP caused PPARγ protein translocation to the nucleus in neurons in the CA1 region of the hippocampus. Pretreatment with GW9962, a PPARγ inhibitor, significantly attenuated the upregulation of Klotho protein and blocked the brain ischemic tolerance induced by CIP. Taken together, it can be concluded that Klotho upregulation via PPARγ contributes to the induction of brain ischemic tolerance by CIP.


Assuntos
Isquemia Encefálica , Precondicionamento Isquêmico , Animais , Ratos , Isquemia Encefálica/metabolismo , Região CA1 Hipocampal , Isquemia , PPAR gama/metabolismo , Ratos Wistar , Regulação para Cima
5.
J Environ Manage ; 325(Pt B): 116519, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36326522

RESUMO

Pyrolysis of wastes usually produces toxic pyrolysis oil (PO), which has complex ingredients, including benzene series and long-chain macromolecule organic pollutants. Co-anaerobic digestion (co-AD) can be an economic and high-efficiency method for PO degradation and recovery of methane simultaneously, but complete degradation of PO has not been achieved yet. Addition of a hydro-char in the process is beneficial to PO degradation and methane production. In this study, to further enhance the effectiveness of the hydro-char, nitrogen (N) was doped into the hydro-char by plasma modification in a NH3 atmosphere; and the effectiveness of the N-doped hydro-chars for promoting PO degradation and methane production during the co-AD process were evaluated. The experimental results indicated that all the hydro-chars can reduce the biotoxicity of the PO, improve its degradation during the co-AD process, and increase the methane yield. Compared with the plain hydro-char (HC), the hydro-chars modified at ambient temperature (HC-NH3-P-25) and at 500 °C (HC-NH3-P-500) can help achieving complete PO degradation and increasing the methane yield more effectively. The anaerobic digestor containing the HC-NH3-P-500 had the highest apparent methane yield (169.03 mLCH4/mLPO) and highest COD removal rate (79.5%). The nitrogen content, specific surface area, and electron transfer capability are found to be the key factors affecting PO degradation and methane yield; and the HC-NH3-P-500 had the highest N-doping, most specific surface area and electron transfer capability, explaining its best performance. The microbial communities of the digestate with the addition of the hydro-chars were founded to be richer with Clostridia and Methanosarcina, which could enhance the electron transfer between different microorganisms and contribute to the PO degradation.


Assuntos
Metano , Pirólise , Anaerobiose , Nitrogênio , Reatores Biológicos
6.
Environ Geochem Health ; 45(11): 8243-8255, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37578561

RESUMO

Small-scale Solid Waste Thermal Treatment (SSWTT) is prevalent in remote Chinese locations. However, the ecological threats associated with heavy metals in resultant bottom ash remain undefined. This research study scrutinized such ash from eight differing sites, assessing heavy metal content, chemical form, and leaching toxicity. Most bottom ash samples met soil contamination standards for development land (GB36600-2018). However, levels of As, Cd, Cr, Cu, Ni, Pb, and Zn in some samples exceeded agricultural land standards GB15618-2018) by 1591%, 64,478%, 1880%, 3886%, 963%, 1110%, and 2011% respectively. Additionally, the As and Cd contents surpassed the construction land control limit value by 383% and 13% respectively. The mean values of the combined oxidizable and residual fraction (F3 + F4) for each heavy metal in all samples exceeded 65%, with Cr, Cu, Ni, and Pb reaching over 95%. All sample leaching concentrations, obtained via the HJ/T 299 procedure, were less than limits set by the identification standards for hazardous wastes (GB5085.3-2007). However, only the leaching concentrations of three samples via the leaching procedure HJ/T 300 met the "Solid Waste Landfill Pollution Control Standard" (GB 16889-2008). The results indicate that the location and type of SSWTT equipment play a crucial role in determining an appropriate solution for bottom ash management.


Assuntos
Cinza de Carvão , Metais Pesados , Cinza de Carvão/análise , Resíduos Sólidos , Cidades , Cádmio , Chumbo , Metais Pesados/análise , Medição de Risco , China , Incineração
7.
J Phys Chem A ; 126(2): 296-305, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34985887

RESUMO

Previous experimental studies have found that biochar after KOH activation can significantly improve the efficiency of NO removal, but its mechanism is still unclear. To investigate the reaction mechanism of this denitration reaction, in this study, the aromatic benzene ring structure was used to simulate the surface of biochar, and the reaction process was calculated by density functional theory (DFT). The reaction process on the pristine biochar was simulated for comparison. The results indicated that there were two potential mechanisms for NO removal and had the identical rate-determining step, with an activation energy of 161.5 kJ/mol. Second, the influence by K coadsorbates on the NO reduction mechanism was studied. The adsorption by K atoms does not alter the last reaction step, but it was found to reduce the activation energy of this rate-determining step (to 129.3 kJ/mol). A third type of reaction mechanism was theoretically studied for the situation with both K and OH coadsorbates on the biochar surface. The reaction mechanism changed with an increase in the overall reaction rate by increasing the pre-exponential factor. In summary, the rate-determining activation energy for the heterogeneous NO reduction was found to decrease in the following order: 161.5 kJ/mol (pristine biochar) → 129.3 kJ/mol (activation by K adsorbates) → 125.8 kJ/mol (activation by both K and OH adsorbates); the pre-exponential factor was found to change in the following order: 6.23 × 1014 s-1 (pristine biochar) → 4.86 × 1014 s-1 (activation by K adsorbates) → 8.89 × 1014 s-1 (activation by K and OH adsorbates). Hence, the role by K adsorbates is primarily to reduce the rate-determining activation energy, while the OH group adsorbate increases the number of active sites on the surface of biochar.

8.
Biotechnol Lett ; 42(4): 669-679, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32048128

RESUMO

Human umbilical cord mesenchymal stem cell-derived exosomes (HucMSC-Ex) are a promising tool for the repair of acute kidney injury (AKI) caused by cisplatin and ischemia/reperfusion. However, the roles of hucMSC-Ex in sepsis-associated AKI repair and its mechanism are largely unknown. Hence, we constructed a sepsis model through cecal ligation and puncture (CLP), testing the benefits of hucMSC-Ex in the sepsis in terms of survival rate, serum renal markers levels, morphological changes and apoptosis. Immunohistochemistry staining and immunofluorescence assay were used to investigate the role of NF-κB activity in the repair of sepsis-associated AKI with hucMSC-Ex. HK-2 cells were transfected with microRNA-146b (miR-146b) mimics and inhibitors, respectively, and the regulatory effect of miR-146b on NF-κB activity was studied. We found that hucMSC-Ex treatment significantly decreased the serum creatinine (Cr) and blood urea nitrogen (BUN) levels, ameliorated the morphological damage and inhibited renal tubular cells apoptosis. More importantly, the survival rate at 72 h was 28% in CLP group and 45% in hucMSC-Ex group, respectively. Treatment with hucMSC-Ex improved survival in mice with sepsis. These effects of hucMSC-Ex were mediated by the inhibition of NF-κB activity and the lessening of pro-inflammatory response. Furthermore, hucMSC-Ex significantly increased miR-146b expression in kidney tissues. Conversely, interleukin (IL)-1 receptor-associated kinase (IRAK1) level, which is the target gene of miR-146b, clearly decreased in hucMSC-Ex group. In brief, this study showed that treatment with hucMSC-Ex decreased IRAK1 expression through the up-regulation of miR-146b level, led to the inhibition of NF-κB activity, and eventually alleviated sepsis-associated AKI and improved survival in mice with sepsis. HucMSC-Ex may be a novel therapeutic agent for the reduction of sepsis-associated AKI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Exossomos/transplante , MicroRNAs/genética , Sepse/terapia , Cordão Umbilical/citologia , Injúria Renal Aguda/microbiologia , Animais , Nitrogênio da Ureia Sanguínea , Linhagem Celular , Cisplatino/efeitos adversos , Creatinina/sangue , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Quinases Associadas a Receptores de Interleucina-1/genética , Masculino , Células-Tronco Mesenquimais/citologia , Camundongos , Sepse/genética
9.
J Environ Sci (China) ; 88: 112-121, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862052

RESUMO

The high content of alkali chlorides in municipal solid waste incineration (MSWI) fly ash limit its resource reuse due to the potential environmental risks. In this paper, with superheated steam as the gasifying agent and inducer, chlorides in fly ash were removed by thermal treatment within a moderate temperature range. Thermal treatment experiments were performed under different conditions: temperature (500-800°C), steam addition (mass ratio of steam to fly ash = 0.25-1) and residence time (0.5-3 hr). Iron and aluminum powders were added to fly ash to improve the chlorine removal efficiency. Water-soluble chlorides included NaCl and KCl, and insoluble chlorides mainly included Ca(OH)Cl. The heating process with the addition of water steam was more efficient than that without steam in terms of the removal performance of water-soluble chlorides. The removal efficiency of soluble chlorides reached 75.25% for a mass ratio of 1:1 after 1-hr thermal treatment at 700°C. When the residence time was increased above 1 hr, the total dechlorination efficiency was not increased dramatically. Moreover, adding iron and aluminum powder into the fly ash improved the removal of water-insoluble chlorides, and the total dechlorination efficiency was increased by 11.41%-16.64%.


Assuntos
Cloro/química , Incineração , Alumínio , Carbono , Cloretos , Cinza de Carvão , Ferro , Material Particulado , Eliminação de Resíduos , Resíduos Sólidos
10.
J Neurochem ; 151(5): 608-625, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31314916

RESUMO

Glial glutamate transporter 1 (GLT-1) plays a vital role in the induction of brain ischemic tolerance (BIT) by ischemic preconditioning (IPC). However, the mechanism still needs to be further explained. The aim of this study was to investigate whether peroxisome proliferator-activated receptor gamma (PPARγ) participates in regulating GLT-1 during the acquisition of BIT induced by IPC. Initially, cerebral IPC induced BIT and enhanced PPARγ and GLT-1 expression in the CA1 hippocampus in rats. The ratio of nuclear/cytoplasmic PPARγ was also increased. At the same time, the up-regulation of PPARγ expression in astrocytes in the CA1 hippocampus was revealed by double immunofluorescence for PPARγ and glial fibrillary acidic protein. Then, the mechanism by which PPARγ regulates GLT-1 was studied in rat cortical astrocyte-neuron cocultures. We found that IPC [45 min of oxygen glucose deprivation (OGD)] protected neuronal survival after lethal OGD (4 h of OGD), which usually leads to neuronal death. The activation of PPARγ occurred earlier than the up-regulation of GLT-1 in astrocytes after IPC, as determined by western blot and immunofluorescence. Moreover, the preadministration of the PPARγ antagonist T0070907 or PPARγ siRNA significantly attenuated GLT-1 up-regulation and the neuroprotective effects induced by IPC in vitro. Finally, the effect of the PPARγ antagonist on GLT-1 expression and BIT was verified in vivo. We observed that the preadministration of T0070907 by intracerebroventricular injection dose-dependently attenuated the up-regulation of GLT-1 and BIT induced by cerebral IPC in rats. In conclusion, PPARγ participates in regulating GLT-1 during the acquisition of BIT induced by IPC. Cover Image for this issue: doi: 10.1111/jnc.14532. Open Science: This manuscript was awarded with the Open Materials Badge For more information see: https://cos.io/our-services/open-science-badges/.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Precondicionamento Isquêmico , PPAR gama/metabolismo , Animais , Isquemia Encefálica/metabolismo , Técnicas In Vitro , Masculino , Neuroglia/metabolismo , Ratos , Ratos Wistar
11.
Neurochem Res ; 43(9): 1779-1790, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29995175

RESUMO

Previous studies have shown that intermittent hypobaric hypoxia (IH) preconditioning protected neurons survival from brain ischemia. However, the mechanism remains to be elucidated. The present study explored the role of nitric oxide (NO) in the process by measuring the expression of NO synthase (NOS) and NO levels. Male Wistar rats (100) were randomly assigned into four groups: sham group, IH + sham group, ischemia group and IH + ischemia group. Rats for IH preconditioning were exposed to hypobaric hypoxia mimicking 5000 m high-altitude (PB = 404 mmHg, PO2 = 84 mmHg) 6 h/day, once daily for 28 days. Global brain ischemia was established by four-vessel occlusion that has been created by Pulsinelli. Rats were sacrificed at 7th day after the ischemia for neuropathological evaluation by thionin stain. In addition, the expression of neuronal NOS (nNOS), inducible NOS (iNOS), and NO content in the hippocampal CA1 subfield were measured at 2nd day and 7th day after the ischemia. Results revealed that global brain ischemia engendered delayed neuronal death (DND), both nNOS and iNOS expression up-regulated, and NO content increased in the hippocampal CA1 subfield. IH preconditioning reduced neuronal injury induced by the ischemia, and prevented the up-regulation of NOS expression and NO production. In addition, L-NAME + ischemia group was designed to detect whether depressing NO production could alleviate the DND. Pre-administration of L-NAME alleviated DND induced by the ischemia. These results suggest that IH preconditioning plays a protective role by inhibiting the over expression of NOS and NO content after brain ischemia.


Assuntos
Isquemia Encefálica/metabolismo , Região CA1 Hipocampal/metabolismo , Hipóxia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Animais , Isquemia Encefálica/patologia , Região CA1 Hipocampal/patologia , Hipóxia/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar
12.
Neurochem Res ; 43(10): 2016, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30171421

RESUMO

The order of corresponding author was inadvertently published. Hence, the first and the second corresponding authors should be Min Zhang (hebmuzhangmin@163.com) and Jing-Ge Zhang (zhangjg001@163.com).

13.
J Neurochem ; 132(2): 194-205, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25270764

RESUMO

Ceftriaxone(Cef) selectively increases the expression of glial glutamate transporter-1 (GLT-1), which was thought to be neuroprotective in some circumstances. However, the effect of Cef on glutamate uptake of GLT-1 was mostly assayed using in vitro studies such as primary neuron/astrocyte cultures or brain slices. In addition, the effect of Cef on neurons in different ischemic models was still discrepant. Therefore, this study was undertaken to observe the effect of Cef on neurons in global brain ischemia in rats, and especially to provide direct evidence of the up-regulation of GLT-1 uptake for glutamate contributing to the neuronal protection of Cef against brain ischemia. Neuropathological evaluation indicated that administration of Cef, especially pre-treatment protocols, significantly prevented delayed neuronal death in hippocampal CA1 subregion normally induced by global brain ischemia. Simultaneously, pre-administration of Cef significantly up-regulated the expression of GLT-1. Particularly, GLT-1 uptake assay with (3) H-glutamate in living cells from adult rats showed that up-regulation in glutamate uptake accompanied up-regulated GLT-1 expression. Inhibition of GLT-1 by antisense oligodeoxynucleotides or dihydrokainate significantly inhibited the Cef-induced up-regulation in GLT-1 uptake and the neuroprotective effect against global ischemia. Thus, we may conclude that Cef protects neurons against global brain ischemia via up-regulation of the expression and glutamate uptake of GLT-1. Glutamate uptake by glial glutamate transporter-1 (GLT-1) is the principal way to regulate extracellular glutamate homeostasis in central nervous system. Over-accumulation of glutamate results in excitotoxicity and injures neurons after cerebral ischemia. Ceftriaxone up-regulates GLT-1 expression and uptake of glutamate, diminishes the excitotoxicity of glutamate and then protects neurons against global brain ischemia.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Ceftriaxona/uso terapêutico , Transportador 2 de Aminoácido Excitatório/metabolismo , Ácido Glutâmico/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Animais , Transporte Biológico/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Ceftriaxona/administração & dosagem , Ceftriaxona/farmacologia , Avaliação Pré-Clínica de Medicamentos , Transportador 2 de Aminoácido Excitatório/antagonistas & inibidores , Transportador 2 de Aminoácido Excitatório/genética , Técnicas de Silenciamento de Genes , Ácido Caínico/análogos & derivados , Ácido Caínico/farmacologia , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Regulação para Cima
14.
Amino Acids ; 46(6): 1537-45, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24643365

RESUMO

Our previous study has shown that cerebral ischemic preconditioning (CIP) can up-regulate the expression of glial glutamate transporter-1 (GLT-1) during the induction of brain ischemic tolerance in rats. The present study was undertaken to further explore the uptake activity of GLT-1 in the process by observing the changes in the concentration of extracellular glutamate with cerebral microdialysis and high-performance liquid chromatography. The results showed that a significant pulse of glutamate concentration reached the peak value of sevenfold of the basal level after lethal ischemic insult, which was associated with delayed neuronal death in the CA1 hippocampus. When the rats were pretreated 2 days before the lethal ischemic insult with CIP which protected the pyramidal neurons against delayed neuronal death, the peak value of glutamate concentration decreased to 3.9 fold of the basal level. Furthermore, pre-administration of dihydrokainate, an inhibitor of GLT-1, prevented the protective effect of CIP on ischemia-induced CA1 cell death. At the same time, compared with the CIP + Ischemia group, the peak value of glutamate concentration significantly increased and reached sixfold of the basal level. These results indicate that CIP induced brain ischemic tolerance via up-regulating GLT-1 uptake activity for glutamate and then decreasing the excitotoxicity of glutamate.


Assuntos
Transportador 2 de Aminoácido Excitatório/biossíntese , Ácido Glutâmico/metabolismo , Precondicionamento Isquêmico , Animais , Transportador 2 de Aminoácido Excitatório/metabolismo , Hipocampo/metabolismo , Ácido Caínico/análogos & derivados , Ácido Caínico/farmacologia , Masculino , Microdiálise , Ratos Wistar , Regulação para Cima
15.
ACS Appl Mater Interfaces ; 16(29): 37641-37655, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38991175

RESUMO

Enrichment and quantification of sugar phosphates (SPx) in biological samples were of great significance in biological medicine. In this work, a series of zirconium-based metal-organic frameworks (MOFs) with different degrees of defects, namely, HP-UiO-66-NH2-X, were synthesized using acetic acid as a modulator and were utilized as high-capacity adsorbents for the adsorption of SPx in biological samples. The results indicated that the addition of acetic acid altered the morphology of HP-UiO-66-NH2-X, with corresponding changes in pore size (3.99-9.28 nm) and specific surface area (894.44-1142.50 m2·g-1). HP-UiO-66-NH2-10 showed the outstanding performance by achieving complete adsorption of all four SPx using only 80 µg of the adsorbent. The excellent adsorption efficiency of HP-UiO-66-NH2-10 was also obtained with a wide pH range and short adsorption time (10 min). Adsorption experiments demonstrated that the adsorption process involved chemical adsorption and multilayer adsorption. By utilizing X-ray photoelectron spectroscopy and density functional theory to explain the adsorption mechanism, it was found that various interactions (including coordination, hydrogen bonding, and electrostatic interactions) collectively contributed to the exceptional adsorption capability of HP-UiO-66-NH2-10. Those results indicated that the defect strategy not only increased the specific surface area and pore size, providing additional adsorption sites, but also reduced the adsorption energy between HP-UiO-66-NH2-10 and SPx. Moreover, HP-UiO-66-NH2-10 showed a low limit of detection (0.001-0.01 ng·mL-1), high precision (<13.77%), and accuracy (80.10-111.83%) in serum, liver, and cells, good stability, high selectivity (SPx/glucose, 1:100 molar ratio), and high adsorption capacity (292 mg·g-1 for SPx). The practical detection of SPx from human serum was also verified, prefiguring the great potentials of defective zirconium-based MOFs for the enrichment and detection of SPx in the biological medicine.


Assuntos
Estruturas Metalorgânicas , Zircônio , Zircônio/química , Estruturas Metalorgânicas/química , Adsorção , Humanos , Fosfatos/química , Ácidos Ftálicos
16.
Anal Chim Acta ; 1317: 342908, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39030009

RESUMO

BACKGROUND: Sugar phosphates (SPx) play important role in the metabolism of the organism. SPx such as glycerate 3-phosphate, fructose 6-phosphate and glucose 6-phosphate in biological samples have the poor stability, similar structure and low abundance, which make their separation and detection more challenging. METHOD: UiO-66-NH2 and ZrO2 coated SiO2(SBA-15) hard-core-shell adsorbents (UiO-66-NH2@SBA-15 and ZrO2@SBA-15) were synthesized, which were further used for dispersive solid-phase extraction for enriching the SPx in biological samples. The protocol was developed by UiO-66-NH2@SBA-15 and ZrO2@SBA-15 coupled with gas chromatography-mass spectrometry for the detection of trace SPx. The univariate experiment and response surface methodology were used to optimize the adsorption and desorption conditions. RESULTS: The adsorbents showed excellent adsorption capacity and specificity towards SPx, which were proved by adsorption and selective experiments. Under the optimized conditions, there were good linearity within the range of 5.0-5000.0 ng mL-1, low limits of detection (0.001-1.0 ng mL-1), low limits of quantification (0.005-5.0 ng mL-1) and good precision (relative standard deviation less than 14.7 % for intra-day and inter-day). The satisfactory recoveries (89.1-113.8 %) and precision (0.5-14.6 %) were obtained when the sorbents were used to extract SPx from serum, saliva and cell samples. Moreover, UiO-66-NH2@SBA-15 was applied to the quantitative analysis of SPx from gastric cancer patients, because of a higher adsorption capacity (169.5-196.1 mg g-1). CONCLUSIONS: UiO-66-NH2@SBA-15 showed great potential in the extraction of SPx in biological samples, which was beneficial to find out the metabolic change of SPx and explain the pathogenesis of the disease.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Estruturas Metalorgânicas , Dióxido de Silício , Extração em Fase Sólida , Zircônio , Zircônio/química , Extração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Estruturas Metalorgânicas/química , Humanos , Dióxido de Silício/química , Adsorção , Limite de Detecção , Fosfatos/química , Ácidos Ftálicos
17.
Neuropharmacology ; 261: 110139, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39233201

RESUMO

Cognitive dysfunction is an important comorbidity of type 2 diabetes mellitus (T2DM). Sodium butyrate (NaB) is a short-chain fatty acid and has an effect improving T2DM-associated cognitive dysfunction. Using a high-fat diet (HFD)/streptozotocin (STZ)-induced T2DM mouse model, the present study investigated the mechanism involved in the beneficial effect of butyrate on diabetic cognitive dysfunction, with a focus on ameliorating mitochondrial damage through regulating the adenosine monophosphate-activated protein kinase/peroxisome proliferator-activated receptor gamma coactivator 1α (AMPK/PGC-1α) pathway considering the important role of mitochondrial impairments in the occurrence of T2DM-associated cognitive dysfunction. We found, based on reconfirmation of the improvement of NaB on cognitive impairment, that NaB treatment improved damaged synaptic structural plasticity including the decrease in dendritic spine density and downregulation in the expression of postsynaptic density protein 95 and synaptophysin in the hippocampus in the model mice. NaB treatment also ameliorated mitochondrial ultrastructural damage, increased mitochondrial membrane potential and adenosine 5'-triphosphate content, and improved mitochondrial biogenesis and dynamics in the model mice. Furthermore, the expression of phosphorylated AMPK and PGC-1α was upregulated after NaB treatment in the model mice. In particular, the above beneficial effects of NaB were blocked by the inhibition of either AMPK or PGC-1α. In conclusion, NaB treatment improved cognitive impairment and damaged synaptic structural plasticity in the hippocampus by ameliorating damage to mitochondrial morphology and function through regulating the AMPK/PGC-1α pathway in HFD/STZ-induced T2DM mice.

18.
Sci Rep ; 14(1): 17703, 2024 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085289

RESUMO

Renal interstitial fibrosis (RIF) is a prevalent consequence of chronic renal diseases, characterized by excessive extracellular matrix (ECM) deposition. A Disintegrin and Metalloprotease 17 (ADAM17), a transmembrane metalloproteinase, plays a central role in driving renal fibrosis progression by activating Notch 1 protein and the downstream TGF-ß signaling pathway. Our study investigated potential therapeutic interventions for renal fibrosis, focusing on human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hucMSC-EVs). We found that hucMSC-EVs inhibit ADAM17, thereby impeding renal fibrosis progression. Analysis of hucMSC-EVs miRNA profiles revealed significant enrichment of miR-13474, which effectively targeted and inhibited ADAM17 mRNA expression, subsequently suppressing Notch1 activation, TGF-ß signaling, and collagen deposition. Overexpression of miR-13474 enhanced hucMSC-EVs' inhibitory effect on renal fibrosis, while its downregulation abolished this protective effect. Our findings highlight the efficacy of hucMSC-EVs overexpressing miR-13474 in mitigating renal fibrosis via ADAM17 targeting. These insights offer potential therapeutic strategies for managing renal fibrosis.


Assuntos
Proteína ADAM17 , Vesículas Extracelulares , Fibrose , Rim , Células-Tronco Mesenquimais , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína ADAM17/metabolismo , Proteína ADAM17/genética , Humanos , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Rim/metabolismo , Rim/patologia , Transdução de Sinais , Nefropatias/metabolismo , Nefropatias/terapia , Nefropatias/patologia , Nefropatias/genética , Fator de Crescimento Transformador beta/metabolismo , Camundongos
19.
Waste Manag ; 186: 11-22, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38843559

RESUMO

The fast development of the waste incineration industry requires deeper insights into heating surface corrosion behavior at higher operating parameters with complex corrosion sources. This research investigates the corrosion behaviors of three types of plates, namely SA210-C, TP310, and 12CrMoV, when subjected to simulated flue gas and fly ash deposition simultaneously at temperatures ranging from 500℃ to 620℃. The results indicate that the weight loss due to coupling corrosion was 2.5 to 84.5 times higher than that of gas-phase corrosion under the same operating conditions. Among the three stainless-steels, TP310 demonstrates superior corrosion resistance. It is worth noting that, under the gas-solid coupling corrosion conditions, we observed a distinct two-layer structure of corrosion products. Despite the fly ash simulants detaching over time, the two-layer structure remained unchanged. Based on the theory of eutectic molten salt formation, we propose that alkali metal chlorides only initiate the formation of the molten layer in the initial stage of corrosion. Furthermore, we offer additional suggestions for the mechanism of sustaining the molten layer in the absence of alkali metal chlorides.


Assuntos
Cloro , Cinza de Carvão , Incineração , Aço Inoxidável , Incineração/métodos , Corrosão , Cinza de Carvão/química , Cloro/química , Aço Inoxidável/química , Vapor/análise , Gases/química
20.
Mol Neurobiol ; 61(4): 2270-2282, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37870679

RESUMO

The morbidity rate of ischemic stroke is increasing annually with the growing aging population in China. Astrocytes are ubiquitous glial cells in the brain and play a crucial role in supporting neuronal function and metabolism. Increasing evidence shows that the impairment or loss of astrocytes contributes to neuronal dysfunction during cerebral ischemic injury. The mitochondrion is increasingly recognized as a key player in regulating astrocyte function. Changes in astrocytic mitochondrial function appear to be closely linked to the homeostasis imbalance defects in glutamate metabolism, Ca2+ regulation, fatty acid metabolism, reactive oxygen species, inflammation, and copper regulation. Here, we discuss the role of astrocytic mitochondria in the pathogenesis of brain ischemic injury and their potential as a therapeutic target.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Humanos , Idoso , Astrócitos/metabolismo , Isquemia Encefálica/patologia , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Mitocôndrias/metabolismo
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