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1.
ChemSusChem ; : e202401311, 2024 Aug 19.
Article de Anglais | MEDLINE | ID: mdl-39158369

RÉSUMÉ

Pitch-based porous carbons with adjustable surface chemical property and controllable pore structure are regarded as promising cathode materials for aqueous zinc-ion hybrid capacitors (ZIHCs), while its disordered carbon matrix and microstructure as well as insufficient surface defects often result in low Zn2+-storage capacity and poor rate capability of ZIHCs. Herein, a synergetic strategy of self-assembled supermolecule and enriched defective carbon engineering was developed to achieve ultrahigh edge-nitrogen doping for ZIHCs. The crystallite defects and surface structure of porous carbon could be effectively achieved through grafting electronegative oxygen-containing small molecules and high-level nitrogen-containing functional groups between modified polycyclic aromatic hydrocarbon and supermolecule framework. The optimized three-dimensional carbon structure delivered high capacity of 218 mAh g-1 at 0.2 A g-1, fast charge/discharge capability, enhanced energy density (165.4 Wh kg-1) and superior cycling stability (95% retention after 10000 cycles as cathode of ZIHCs). This provided new insight into the controllable synthesis of carbon cathodes for ZIHCs and expects to prepare functional porous carbon by supermolecules and special precursors.

2.
J Colloid Interface Sci ; 640: 391-404, 2023 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-36867936

RÉSUMÉ

The development of high-performance bifunctional electrocatalysts for oxygen evolution reaction and heavy metal ion (HMI) detection is significant and challenging. Here, a novel nitrogen, sulfur co-doped porous carbon sphere bifunctional catalyst was designed and fabricated by hydrothermal followed by carbonization using starch as carbon source and thiourea as nitrogen, sulfur source for HMI detection and oxygen evolution reactions. Under the synergistic effect of pore structure, active sites and nitrogen, sulfur functional groups, C-S0.75-HT-C800 demonstrated excellent HMI detection performance and oxygen evolution reaction activity. Under optimized conditions, the detection limits (LODs) of C-S0.75-HT-C800 sensor were 3.90, 3.86 and 4.91 nM for Cd2+, Pb2+ and Hg2+ when detected individually; and the sensitivities were 13.12, 19.50 and 21.19 µA/µM. The sensor also obtained high recoveries of Cd2+, Hg2+ and Pb2+ in river water samples. During the oxygen evolution reaction, a Tafel slope of 70.1 mV/dec and a low overpotential of 277 mV were obtained for C-S0.75-HT-C800 electrocatalyst with a current density of 10 mA/cm2 in basic electrolyte. This research offers a neoteric and simple strategy in the design as well as fabrication of bifunctional carbon-based electrocatalysts.

3.
Molecules ; 28(3)2023 Jan 21.
Article de Anglais | MEDLINE | ID: mdl-36770763

RÉSUMÉ

The physical and chemical properties of spinnable pitch showed a huge impact on the performance of resultant pitch carbon fiber even if its physical and chemical properties were slightly changed. Various polycyclic aromatic compounds and abundant free radicals existed in spinnable pitch, and there are many interactions among molecules and free radicals. The molecular structure and composition of spinnable pitch were investigated during incubation, and the effect of molecular evaluation on rheological properties of spinnable pitch was illustrated using various characterization methods in this work. It indicated that n-hexane soluble fraction mainly occurred condensation or cleavage, and a small number of heavy components were generated after a long period. The fraction of n-hexane insoluble/toluene soluble underwent molecular condensation and cross-linking in the presence of oxygen-containing radicals and aromatic hydrocarbon radicals, while toluene insoluble/tetrahydrofuran soluble fraction tended to change in large molecules of polycyclic aromatic hydrocarbons. Lastly, tetrahydrofuran insoluble fraction was condensed due to its high aromaticity during the incubation process, and the content of aromatic carbon increased. These changes of composition and structure of spinnable pitch led to its softening point, increase in viscosity and flow activation energy, and deterioration of the rheological property.

4.
ACS Appl Mater Interfaces ; 13(8): 9838-9845, 2021 Mar 03.
Article de Anglais | MEDLINE | ID: mdl-33595271

RÉSUMÉ

The fast recombination of photogenerated charge carriers and poor stability have impeded the application of many narrow band gap semiconductors with otherwise excellent photocatalytic performance. A metal-semiconductor Schottky junction is a promising strategy to accelerate charge separation and enhance catalytic efficiency. However, the preparation of these structures often involves intricate processes and harsh conditions, which will inevitably destroy the electronic structures of the semiconductors and ruin their original properties in practical applications. In this study, a reduced graphene oxide (RGO)-enwrapped Cu-Cu2O nanocomposite (Cu-Cu2O@RGO) spontaneously evolved from an aqueous alcoholic solution containing cupric ions and graphene oxide (GO) under simulated sunlight irradiation. During this process, GO reduction and Cu-Cu2O nanoparticles growth occurred simultaneously in conjunction with in situ RGO encapsulation. Benefiting from the superior intrinsic semiconductor characteristic retention under mild reaction conditions, strong component interactions, and efficient interfacial charge transfer, the distinctive Cu-Cu2O@RGO nanocomposite supplied multiple channels for rapid electron transfer to substantially enhance the charge carrier separation efficiency and provide perfect chemical protection to effectively prevent Cu2O photocorrosion. This product also greatly suppressed self-aggregation to decrease the size of nanoparticles. Based on these merits, the Cu-Cu2O@RGO nanocomposite offered promising advances in photoelectrochemical and photocatalytic H2 evolution. This work provides an innovative photoinduced strategy for constructing an RGO-enwrapped semiconductor nanocomposite with efficient charge transfer interfaces while providing novel insights for the efficient solar energy utilization.

6.
Proc Natl Acad Sci U S A ; 115(16): 4218-4222, 2018 04 17.
Article de Anglais | MEDLINE | ID: mdl-29610342

RÉSUMÉ

Reactive oxygen species formed within the mammalian cell can produce 8-oxo-7,8-dihydroguanine (8-oxoG) in mRNA, which can cause base mispairing during gene expression. Here we found that administration of 8-oxoGTP in MTH1-knockdown cells results in increased 8-oxoG content in mRNA. Under this condition, an amber mutation of the reporter luciferase is suppressed. Using second-generation sequencing techniques, we found that U-to-G changes at preassigned sites of the luciferase transcript increased when 8-oxoGTP was supplied. In addition, an increased level of 8-oxoG content in RNA induced the accumulation of aggregable amyloid ß peptides in cells expressing amyloid precursor protein. Our findings indicate that 8-oxoG accumulation in mRNA can alter protein synthesis in mammalian cells. Further work is required to assess the significance of these findings under normal physiological conditions.


Sujet(s)
Guanine/analogues et dérivés , Mutagenèse/génétique , Biosynthèse des protéines/génétique , Transcription génétique/génétique , Peptides bêta-amyloïdes/génétique , Anticodon/génétique , Appariement de bases , Codon non-sens , Enzymes de réparation de l'ADN/antagonistes et inhibiteurs , Enzymes de réparation de l'ADN/génétique , Techniques de knock-down de gènes , Gènes rapporteurs , Guanine/composition chimique , Cellules HeLa , Humains , Luciferases/génétique , Phosphoric monoester hydrolases/antagonistes et inhibiteurs , Phosphoric monoester hydrolases/génétique , Interférence par ARN , ARN messager/biosynthèse , ARN messager/génétique , Petit ARN interférent/génétique , Espèces réactives de l'oxygène
7.
Oncotarget ; 8(37): 61193-61202, 2017 Sep 22.
Article de Anglais | MEDLINE | ID: mdl-28977856

RÉSUMÉ

Deficits in mitochondrial function is a critical inducement in the major pathways that drive neuronal cell death in ischemic process particularly. Drugs target to improve the mitochondrial function may be a feasible therapeutic choice in treatment with ischemic diseases. In the present study, we investigated whether 5-(4-hydroxy-3-dimethoxybenzylidene)-2-thioxo-4-thiazolidinone (RD-1), a compound derived from rhodanine, could protect against ischemic neuronal damage via improving mitochondrial function. We tested the neuroprotective effect of RD-1 both in rats modeled by middle cerebral artery occlusion reperfusion in vivo and in primary cortical neurons subjected to hypoxia/reperfusion injury in vitro. Results showed that treatment with RD-1 for 14 days remarkably reduced infarct size, decreased neurological deficit score and accelerated the recovery of somatosensory function in vivo. Meanwhile, RD-1 also increased the cellular viability after 48 h treatment in vitro. In addition, RD-1 protected the primary cortical neurons against mitochondrial damage as evidenced by stabilizing the mitochondrial membrane potential and reducing the overproduction of reactive oxygen species. Furthermore, hypoxia/reperfusion injury induced damaged mitochondrial axonal transport and consequently neurotransmitter release disorder, which were ameliorated by RD-1 treatment. Besides, RD-1 inhibited the downregulation of proteins related with mitochondrial transport and neurotransmitter release induced by ischemic injury both in vivo and in vitro. The obtained data demonstrated the neuroprotective effect of RD-1 and the involved mechanisms were partially attributed to the improvement in mitochondrial function and the synaptic activity. Our study indicated that RD-1 may be a potential therapeutic drug for the ischemic stroke therapy.

8.
Neuropsychiatr Dis Treat ; 13: 927-935, 2017.
Article de Anglais | MEDLINE | ID: mdl-28392696

RÉSUMÉ

BACKGROUND: Compound porcine cerebroside and ganglioside injection (CPCGI) is a neurotrophic drug used clinically to treat certain functional disorders of brain. Despite its extensive usage throughout China, the exact mechanistic targets of CPCGI are unknown. This study was carried out to investigate the protective effect of CPCGI against ischemic neuronal damage in rats with middle cerebral artery occlusion (MCAO) reperfusion injury and to investigate the neuroprotective mechanisms of CPCGI. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were subjected to MCAO surgery for 2 hours followed by reperfusion. The rats were administered CPCGI once a day for 14 days after reperfusion, and behavioral tests were performed 1, 3, 7, and 14 days post MCAO. Hematoxylin-eosin staining was used to measure infarct volume, and immunohistochemical analysis was performed to determine the number of NeuN-positive neurons in the ischemic cortex penumbra. Finally, the relative expression levels of proteins associated with apoptosis (Bcl-2, Bax, and GADD45α), synaptic function (Synaptophysin, SNAP25, Syntaxin, and Complexin-1/2), and mitochondrial function (KIFC2 and UCP3) were determined by Western blot. RESULTS: CPCGI treatment reduced infarct size, decreased neurological deficit scores, and accelerated the recovery of somatosensory function 14 days after MCAO. In addition, CPCGI reduced the loss of NeuN-positive cells in the ischemic cortex penumbra. In the ischemic cortex, CPCGI treatment decreased GADD45α expression, increased the Bcl-2/Bax ratio, augmented Synaptophysin, SNAP25, and Complexin-1/2 expression, and increased the expression of KIFC2 and UCP3 compared with sham rats 14 days after MCAO reperfusion injury. CONCLUSION: CPCGI displays neuroprotective properties in rats subjected to MCAO injury by inhibiting apoptosis and improving synaptic and mitochondrial function.

9.
Psychiatry Res ; 245: 141-147, 2016 Nov 30.
Article de Anglais | MEDLINE | ID: mdl-27543827

RÉSUMÉ

Low response rate was witnessed with the present monoaminergic based antidepressants, urging a need for new therapeutic target identification. Accumulated evidences strongly suggest that mitochondrial deficit is implicated in major depression and 18kDa translocator protein (TSPO) plays an important role in regulating mitochondrial function. However the changes of TSPO and TSPO mediated mitophagy pathway in the depressive brain is unclear. In present study, a well validated animal model of depression, learned helplessness (LH), was employed to investigate the relevant changes. Significant behavioral changes were observed in the LH mice. Results showed that TSPO and other mitophagy related proteins, such as VDAC1, Pink1 and Beclin1 were significantly decreased by LH challenge. Moreover, KIFC2, relevant to the mitochondrial transport and Snap25, relevant to neurotransmitter vesicle release, were also obviously down-regulated in the LH mice, which further rendered supportive evidence for the existing mitochondrial dysfunction in LH mice. Present results demonstrated that LH induced depressive symptoms and affected TSPO-mediated mitophagy pathway, indicating a potential target candidate for depression treatment.


Sujet(s)
Encéphale/métabolisme , Trouble dépressif majeur/génétique , Expression des gènes/génétique , Impuissance apprise , Mitophagie/génétique , Récepteurs GABA/génétique , Transduction du signal/génétique , Animaux , Antidépresseurs/usage thérapeutique , Dépression/traitement médicamenteux , Régulation négative/génétique , Mâle , Souris , Souris de lignée ICR , Canal anionique-1 voltage-dépendant , Canaux anioniques voltage-dépendants/génétique
10.
Chin J Integr Med ; 22(11): 832-839, 2016 Nov.
Article de Anglais | MEDLINE | ID: mdl-27225293

RÉSUMÉ

OBJECTIVE: To determine the effect of medicated serum of Chinese herbal compound Naofucong (, NFC) on the microglia BV-2 cells viability and the transcription and expression of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in microglia BV-2 cells to further explore the mechanisms underlying the protective effect of NFC on inflammatory process induced by high glucose. METHODS: The microglia BV-2 cells incubated in vitro were divided into different groups: the control group (25 mmol/L glucose), the model group (75 mmol/L glucose), high glucose media containing different dose medicated serum of NFC. After being cultured for 24 h, changes in IL-6 and TNF-α were measured by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. The expression of surface marker CD11b of activated microglia was measured by confocal laser scanning microscope and Western blot. Nuclear factor-κB (NF-κB) p-p65 expression was analyzed by Western blot. RESULTS: The model group obviously increased the expression of microglial surface marker CD11b and NF-κB p-p65 (all P<0.01), induced a signifificant up-regulation of release and the mRNA expression of IL-6 and TNF-α (P<0.01 or P<0.05). The medicated serum of NFC could obviously down-regulate the transcription and expression of surface marker CD11 b and NF-κB p-p65 (all P<0.01), and inhibit the mRNA and protein expression (P<0.01 or P<0.05) of inflflammatory cytokines, such as IL-6 and TNF-α, in microglia BV-2 cells cultured with high glucose for 24 h. CONCLUSIONS: The inhibition of microglial activation and IL-6 and TNF-α expression induced by high glucose may at least partly explain NFC therapeutic effects on diabetes-associated cognitive decline diseases. Its underlying mechanism could probably be related to the inhibition of NFC on NF-κB phosphorylation.


Sujet(s)
Médicaments issus de plantes chinoises/usage thérapeutique , Glucose/toxicité , Inflammation/traitement médicamenteux , Inflammation/anatomopathologie , Animaux , Marqueurs biologiques/métabolisme , Technique de Western , Antigènes CD11b/génétique , Antigènes CD11b/métabolisme , Lignée cellulaire , Forme de la cellule/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Médicaments issus de plantes chinoises/pharmacologie , Test ELISA , Technique d'immunofluorescence , Interleukine-6/génétique , Interleukine-6/métabolisme , Mâle , Souris , Microscopie confocale , ARN messager/génétique , ARN messager/métabolisme , Rat Wistar , Réaction de polymérisation en chaine en temps réel , Facteur de transcription RelA/métabolisme , Facteur de nécrose tumorale alpha/génétique , Facteur de nécrose tumorale alpha/métabolisme
11.
J Ethnopharmacol ; 186: 181-188, 2016 Jun 20.
Article de Anglais | MEDLINE | ID: mdl-27063986

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: Wuling powder (trade name: Wuling capsule), a traditional Chinese medicine (TCM), was extracted from mycelia of precious Xylaria Nigripes (Kl.) Sacc by modern fermentation technology, and has been claimed to be fully potent in improving the signs of insomnia and cognitive deficits. Moreover, Wuling capsule was effective in treating post-stroke and orther co-cormbid depression both in clinical and in basic research. In order to clarify the molecular mechanisms of the antidepressant effect of Wuling powder, we established learned helplessness (LH) depression animal model and focused on 18kDa translocator protein (TSPO) mediated-mitophagy pathway. MATERIALS AND METHODS: Mice were exposed to the inescapable e-shock (IS) once a day for three consecutive days to establish the LH model. Then mice were orally administered Wuling powder for 2 weeks. For the behavioral assessment, Shuttle box test, novelty suppressed feeding test (NSF) and forced swimming test (FST) were performed. Following the behavioral assessment, we assessed the protein expression level that were related to TSPO-mediated mitophagy signaling pathway by Western blotting analysis. Finally, immunohistochemistry method was used to assess the neuroprotective effects of Wuling powder. RESULTS: Compared with mice that were subjected to inescapable e-shock, Wuling powder exhibited antidepressant effect in the multiple behavioral tests. In addition, Wuling powder altered the expression level of multiple proteins related to TSPO-mediated mitophagy signaling pathway. CONCLUSIONS: Our results suggested that Wuling powder exhibited an obvious antidepressant effect, which could be due to the improvement of TSPO-mediated mitophagy signaling pathway.


Sujet(s)
Antidépresseurs/pharmacologie , Médicaments issus de plantes chinoises/pharmacologie , Impuissance apprise , Mitophagie/effets des médicaments et des substances chimiques , Récepteurs GABA/métabolisme , Animaux , Médicaments issus de plantes chinoises/administration et posologie , Fluoxétine/pharmacologie , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Mâle , Mésencéphale/effets des médicaments et des substances chimiques , Mésencéphale/métabolisme , Souris , Souris de lignée ICR , Répartition aléatoire , Récepteurs GABA/génétique , Inbiteurs sélectifs de la recapture de la sérotonine/pharmacologie , Transduction du signal/physiologie
12.
J Alzheimers Dis ; 52(2): 483-95, 2016 03 16.
Article de Anglais | MEDLINE | ID: mdl-27003214

RÉSUMÉ

Alzheimer's disease (AD) is the most common neurodegenerative disorder in the elderly population. Neuroinflammation induced by amyloid-ß (Aß) aggregation is considered to be the critical factor underlying AD pathological mechanisms. Alternatively activated (M2) macrophages/microglia have been reported to have neuroprotective effects in neurodegenerative disease. In this study, we characterized the neuroprotective effects of M2 macrophage transplantation in AD model rats and investigated the underlying mechanisms. Intracerebroventricular injection of Aß1 - 42 to rats was used to model AD and resulted in cognitive impairment, neuronal damage, and inflammatory changes in the brain microenvironment. We observed an increased interferon regulatory factor (IRF) 5/IRF4 ratio, resulting in greater production of classically activated (M1) versus M2 microglia. M2 macrophage transplantation attenuated inflammation in the brain, reversed Aß1 - 42-induced changes in the IRF4-IRF5 ratio, drove endogenous microglial polarization toward the M2 phenotype, and ameliorated cognitive impairment. Nerve growth factor (NGF) treatment reduced the IRF5/IRF4 ratio and induced primary microglial polarization to the M2 phenotype in vitro; these effects were prevented by tyrosine Kinase Receptor A (TrkA) inhibition. M2 macrophage transplantation restored the balance of IRF4-IRF5 by affecting the expression of NGF and inflammatory cytokines in the brains of AD model rats. This drove microglial polarization to the M2 phenotype, promoted termination of neuroinflammation, and resulted in improved cognitive abilities.


Sujet(s)
Peptides bêta-amyloïdes/métabolisme , Dysfonctionnement cognitif/immunologie , Dysfonctionnement cognitif/thérapie , Macrophages/métabolisme , Macrophages/transplantation , Microglie/métabolisme , Fragments peptidiques/métabolisme , Peptides bêta-amyloïdes/administration et posologie , Animaux , Transplantation de moelle osseuse/méthodes , Encéphale/effets des médicaments et des substances chimiques , Encéphale/immunologie , Encéphale/anatomopathologie , Cellules cultivées , Dysfonctionnement cognitif/anatomopathologie , Modèles animaux de maladie humaine , Facteurs de régulation d'interféron/métabolisme , Activation des macrophages/physiologie , Macrophages/effets des médicaments et des substances chimiques , Macrophages/anatomopathologie , Mâle , Apprentissage du labyrinthe/effets des médicaments et des substances chimiques , Apprentissage du labyrinthe/physiologie , Troubles de la mémoire/immunologie , Troubles de la mémoire/anatomopathologie , Troubles de la mémoire/thérapie , Microglie/effets des médicaments et des substances chimiques , Microglie/anatomopathologie , Facteur de croissance nerveuse/administration et posologie , Facteur de croissance nerveuse/métabolisme , Neuro-immunomodulation/effets des médicaments et des substances chimiques , Neuro-immunomodulation/physiologie , Fragments peptidiques/administration et posologie , Répartition aléatoire , Rats de lignée F344 , Récepteur trkA/antagonistes et inhibiteurs , Récepteur trkA/métabolisme
13.
Neuropharmacology ; 105: 587-593, 2016 06.
Article de Anglais | MEDLINE | ID: mdl-26926430

RÉSUMÉ

Most current pharmacologic antidepressant treatments target monoaminergic systems confronts some problems such as low rate of remission and high risk for relapse indicating new therapeutic strategy is urgently need. Evidences showed that impairments in mitochondrial function were associated with the pathogenesis of mood disorders and improvement in its function may be a novel therapeutic choice. In the present study, effects of 5-(4-hydroxy-3-dimethoxybenzylidene)-2-thioxo-4-thiazolidinone (RD-1) were investigated in mice model of depression/anxiety induced by corticosterone (20 mg/kg) subcutaneously repeated injections in 5-week male BALB/c mice. Our results showed that five weeks of corticosterone administration induced anxiety/depressive-like behavioral changes, including decreased central activities in open field test, increased the immobility time in forced swimming test and the latency in the novelty-suppressed feeding test, as well as reduced bodyweight. Results showed that oral administration with RD-1 at the doses of 25, 50, and 100 mg/kg for five weeks significantly improved the anxiety/depressive-like behavioral changes induced by corticosterone. In glucose metabolism analysis by photon emission computed tomography/-computed tomography (PET/CT) imaging, corticosterone significantly deactivated the prefrontal cortex (PFC), temporal lobe and hippocampus. RD-1 treatment obviously improved the energy metabolism in the involved brain regions. In primary cultured hippocampal neuron, corticosterone reduced speed of anterograde transport, yet speed of retrograde transport was increased. Furthermore, RD-1 enhanced the mitochondrial anterograde transport to supply energy for the neurotransmitter release. In conclusion, RD-1 prevents anxiety/depressive-like behavior of mice induced by corticosterone repeated injections with novel mechanism of improvement in the mitochondrial function.


Sujet(s)
Anxiolytiques/pharmacologie , Antidépresseurs/pharmacologie , Troubles anxieux/traitement médicamenteux , Trouble dépressif/traitement médicamenteux , Mitochondries/effets des médicaments et des substances chimiques , Rhodanine/analogues et dérivés , Administration par voie orale , Animaux , Troubles anxieux/imagerie diagnostique , Troubles anxieux/métabolisme , Transport biologique/effets des médicaments et des substances chimiques , Transport biologique/physiologie , Encéphale/imagerie diagnostique , Encéphale/effets des médicaments et des substances chimiques , Encéphale/métabolisme , Cellules cultivées , Corticostérone , Trouble dépressif/imagerie diagnostique , Trouble dépressif/métabolisme , Modèles animaux de maladie humaine , Relation dose-effet des médicaments , Évaluation préclinique de médicament , Mâle , Souris , Souris de lignée BALB C , Mitochondries/métabolisme , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Répartition aléatoire , Rat Sprague-Dawley , Rhodanine/pharmacologie
14.
Anticancer Agents Med Chem ; 16(4): 501-18, 2016.
Article de Anglais | MEDLINE | ID: mdl-26299665

RÉSUMÉ

Accumulated evidences suggested that microRNAs (miRs) play an important role in non-small cell lung cancer (NSCLC). However, how miRs perform their functions in lung adenocarcinoma cancer stem cells (CSCs) remains unknown. Notably, most studies pay more attention to the effects of miRNAs on the metastasis traits whereas the growth activities of CSCs are rather undervalued. In our report, using A549CD133+cells, we examined the inhibitory effects and the underlying mechanisms of microRNA-31 (miR-31) on the growth of lung adenocarcinoma CSC-like cells. Initially, we determined the level of miR-31 in A549 and A549CD133+ cells. Over-expression of miR-31 was found in A549CD133+ cells by microarray and real-time quantitative PCR (RTqPCR) assays. Experiments in multiple NSCLC cell lines in vitro and A549CD133+ cells xenograft models in vivo confirmed that down regulation of miR-31 resulted in increase of A549CD133+ cells growth, whereas overexpression of miR-31 led to the inhibition of adenocarcinoma cell proliferation. Also, MET proto-oncogene has been determined to be a direct target of miR-31 by dual luciferase report, RT-qPCR and western blot analysis. Down regulation of MET inhibited viability of A549CD133+ cells. The levels of PI3Kinase, Akt and p-Akt as well as downstream proteins were consequently decreased. These results suggest that miR-31 might inhibit the growth of lung adenocarcinoma cancer stem-like cells via down regulation of the MET-PI3K-Akt signaling pathway.


Sujet(s)
Adénocarcinome/anatomopathologie , Régulation négative , Tumeurs du poumon/anatomopathologie , microARN/métabolisme , Phosphatidylinositol 3-kinases/déficit , Protéines proto-oncogènes c-akt/déficit , Protéines proto-oncogènes c-met/déficit , Transduction du signal , Adénocarcinome/génétique , Adénocarcinome/métabolisme , Animaux , Apoptose , Prolifération cellulaire , Cellules cultivées , Tests de criblage d'agents antitumoraux , Cellules HEK293 , Humains , Tumeurs du poumon/génétique , Tumeurs du poumon/métabolisme , Mâle , Souris , Souris de lignée BALB C , Souris nude , microARN/biosynthèse , microARN/génétique , Tumeurs expérimentales/traitement médicamenteux , Tumeurs expérimentales/métabolisme , Tumeurs expérimentales/anatomopathologie , Cellules souches tumorales/métabolisme , Cellules souches tumorales/anatomopathologie , Phosphatidylinositol 3-kinases/biosynthèse , Phosphatidylinositol 3-kinases/métabolisme , Proto-oncogène Mas , Protéines proto-oncogènes c-akt/biosynthèse , Protéines proto-oncogènes c-akt/métabolisme , Protéines proto-oncogènes c-met/biosynthèse , Protéines proto-oncogènes c-met/métabolisme
15.
J Control Release ; 221: 26-36, 2016 Jan 10.
Article de Anglais | MEDLINE | ID: mdl-26643616

RÉSUMÉ

Although conventional anticancer drugs exhibit excellent efficacy, serious adverse effects and/or even toxicity have occurred due to their nonselectivity. Moreover, active targeting approaches have not consistently led to successful outcomes. Ligands that simultaneously possess targeting capability and exert a strong influence on intracellular signaling cascades may be expected to improve the therapeutic efficacy of active targeting nanoparticulate carriers. In this study, we screened a targeting peptide, LPLTPLP, which specifically bound to non-small cell lung cancer (NSCLC) specimens in vitro. Surprisingly, this peptide inhibited the expression of Hsp90 and induced apoptosis by preventing autophagy in A549 cells treated with docetaxel. The results suggested that this peptide might be used as a promising dual-functional ligand for cancer treatment. Based on these findings, we designed and developed a novel active targeting delivery system by modifying docetaxel nanoparticles (DNP) with the dual-functional ligand LPLTPLP. We consistently demonstrated that the cellular uptake of nanoparticles (NPs) was significantly enhanced in vitro. Furthermore, the targeting NPs exhibited significantly improved antitumor efficacy and biodistribution compared with nontargeting nanodrug and free docetaxel. These findings demonstrate the feasibility of dual-functional NPs for efficient anticancer therapy.


Sujet(s)
Antinéoplasiques/administration et posologie , Vecteurs de médicaments/composition chimique , Protéines du choc thermique HSP90/métabolisme , Nanoparticules/composition chimique , Peptides/composition chimique , Taxoïdes/administration et posologie , Animaux , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Cellules BALB 3T3 , Carcinome pulmonaire non à petites cellules/traitement médicamenteux , Carcinome pulmonaire non à petites cellules/métabolisme , Carcinome pulmonaire non à petites cellules/anatomopathologie , Lignée cellulaire tumorale , Docetaxel , Systèmes de délivrance de médicaments , Femelle , Protéines du choc thermique HSP90/antagonistes et inhibiteurs , Poumon/effets des médicaments et des substances chimiques , Poumon/métabolisme , Poumon/anatomopathologie , Tumeurs du poumon/traitement médicamenteux , Tumeurs du poumon/métabolisme , Tumeurs du poumon/anatomopathologie , Mâle , Souris , Thérapie moléculaire ciblée , Nanoparticules/ultrastructure , Taxoïdes/pharmacologie , Taxoïdes/usage thérapeutique , Distribution tissulaire
16.
Neural Regen Res ; 10(9): 1457-62, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-26604907

RÉSUMÉ

Lactulose is known to improve cognitive function in patients with early hepatic encephalopathy; however, the underlying mechanism remains poorly understood. In the present study, we investigated the behavioral and neurochemical effects of lactulose in a rat model of early hepatic encephalopathy induced by carbon tetrachloride. Immunohistochemistry showed that lactulose treatment promoted neurogenesis and increased the number of neurons and astrocytes in the hippocampus. Moreover, lactulose-treated rats showed shorter escape latencies than model rats in the Morris water maze, indicating that lactulose improved the cognitive impairments caused by hepatic encephalopathy. The present findings suggest that lactulose effectively improves cognitive function by enhancing neuroplasticity in a rat model of early hepatic encephalopathy.

17.
Restor Neurol Neurosci ; 33(5): 741-59, 2015.
Article de Anglais | MEDLINE | ID: mdl-26444640

RÉSUMÉ

PURPOSE: To investigate the effect and underlying mechanism of Aceglutamide on motor dysfunction in rats after cerebral ischemia-reperfusion. METHODS: Adult male Sprague-Dawley rats were subjected to 2 h transient middle cerebral artery occlusion (MCAO). Aceglutamide or vehicle was intraperitoneally given to rats at 24 h after reperfusion and lasted for 14 days. Subsequently functional recovery was assessed and number of tyrosine hydroxylase (TH)-positive neurons in substantia nigra (SN) was analyzed. Tumor necrosis factor receptor-associated factor 1(TRAF1), P-Akt and Bcl-2/Bax were determined in mesencephalic tissue by Western blot method. PC12 cells and primary cultured mesencephalic neurons were employed to further investigate the mechanism of Aceglutamide. RESULTS: Aceglutamide treatment improved behavioral functions, reduced the infarction volume, and elevated the number of TH-positive neurons in the SN. Moreover, Aceglutamide significantly attenuated neuronal apoptosis in the SN. Meanwhile Aceglutamide treatment significantly inhibited the expression of TRAF1 and up-regulated the expression of P-Akt and Bcl-2/Bax ratio both in vitro and in vivo. CONCLUSIONS: Aceglutamide ameliorated motor dysfunction and delayed neuronal death in the SN after ischemia, which involved the inhibition of pro-apoptotic factor TRAF1 and activation of Akt/Bcl-2 signaling pathway. These data provided experimental information for applying Aceglutamide to ischemic stroke treatment.


Sujet(s)
Encéphalopathie ischémique/traitement médicamenteux , Glutamine/analogues et dérivés , Troubles de la motricité/traitement médicamenteux , Neuroprotecteurs/pharmacologie , Animaux , Encéphalopathie ischémique/anatomopathologie , Mort cellulaire/effets des médicaments et des substances chimiques , Mort cellulaire/physiologie , Cortex cérébral/effets des médicaments et des substances chimiques , Cortex cérébral/métabolisme , Cortex cérébral/anatomopathologie , Modèles animaux de maladie humaine , Relation dose-effet des médicaments , Glutamine/composition chimique , Glutamine/pharmacologie , Infarctus du territoire de l'artère cérébrale moyenne , Injections péritoneales , Mâle , Mésencéphale/effets des médicaments et des substances chimiques , Mésencéphale/métabolisme , Mésencéphale/anatomopathologie , Troubles de la motricité/anatomopathologie , Troubles de la motricité/physiopathologie , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Neurones/anatomopathologie , Neuroprotecteurs/composition chimique , Cellules PC12 , Rats , Rat Sprague-Dawley , Substantia nigra/effets des médicaments et des substances chimiques , Substantia nigra/métabolisme , Substantia nigra/anatomopathologie , Résultat thérapeutique
18.
Int J Pharm ; 494(1): 337-45, 2015 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-26299762

RÉSUMÉ

Small cell lung cancer (SCLC) is one of the most malignant cancers in the world and 5-year survival rate has not been significantly improved with conventional chemotherapy. Targeting treatment may be a promising alternative to enhance the antitumor efficacy. Present study was aimed at establishing a targeting nanodrug delivery system for SCLC therapy. A targeting peptide (AHSGMYP, named AP), screened in H446 cells by phage display technology, was conjugated to the docetaxel (DTX) encapsulated polylactic acid nanoparticles (DN) to prepare the targeting DTX nanoparticles (AP-DN). Cell cytotoxicity, cellular uptake, therapeutic efficacy and biodistribution of AP-DN were investigated in vitro and in vivo experiment. The mean particle size of AP-DN was 260 nm with encapsulation efficiency >94% and a sustained release profile. Cytotoxicity of AP-DN against H446 cell was superior to that of DTX and DN. AP-DN exhibited excellent antitumor efficacy and particularly effectively inhibited the liver metastases with better tolerance. Results of cellular uptake and biodistribution indicated that the excellent antitumor efficacy of AP-DN was attributed to both the increased accumulation of drug and cellular uptake. To our knowledge, this is the first report on establishing SCLC targeting delivery system which offers a potential therapeutic alterative for SCLC therapy.


Sujet(s)
Acide lactique/administration et posologie , Tumeurs du foie/secondaire , Tumeurs du poumon/anatomopathologie , Nanoparticules/administration et posologie , Polymères/administration et posologie , Carcinome pulmonaire à petites cellules/anatomopathologie , Taxoïdes/administration et posologie , Taxoïdes/pharmacologie , Animaux , Antinéoplasiques/administration et posologie , Antinéoplasiques/composition chimique , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Docetaxel , Vecteurs de médicaments/administration et posologie , Vecteurs de médicaments/composition chimique , Tests de criblage d'agents antitumoraux , Humains , Acide lactique/composition chimique , Tumeurs du foie/traitement médicamenteux , Tumeurs du poumon/traitement médicamenteux , Mâle , Souris , Nanoparticules/composition chimique , Taille de particule , Polyesters , Polymères/composition chimique , Carcinome pulmonaire à petites cellules/traitement médicamenteux , Taxoïdes/composition chimique , Taxoïdes/usage thérapeutique
19.
Phys Chem Chem Phys ; 17(35): 23173-82, 2015 Sep 21.
Article de Anglais | MEDLINE | ID: mdl-26278065

RÉSUMÉ

The basic ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]) could efficiently catalyze the conversion of 2-amino-2-deoxy-d-glucose (GlcNH2) into deoxyfructosazine (DOF) and fructosazine (FZ). Mechanistic investigation by NMR studies disclosed that [C2C1Im][OAc], exhibiting strong hydrogen bonding basicity, could coordinate with the hydroxyl and amino groups of GlcNH2via the promotion of hydrogen bonding in bifunctional activation of substrates and further catalyzing product formation, based on which a plausible reaction pathway involved in this homogeneous base-catalyzed reaction was proposed. Hydrogen bonding as an activation force, therefore, is responsible for the remarkable selectivity and rate enhancement observed.


Sujet(s)
Glucosamine/synthèse chimique , Imidazoles/composition chimique , Catalyse , Glucosamine/composition chimique , Spectroscopie par résonance magnétique , Structure moléculaire
20.
Zhonghua Yi Xue Za Zhi ; 95(5): 378-81, 2015 Feb 03.
Article de Chinois | MEDLINE | ID: mdl-26168676

RÉSUMÉ

OBJECTIVE: To explore the changes over time of cannabinoid receptor 1 (CB1R) in hippocampus of status epilepticus (SE) rats. METHODS: A rat model of SE was established by an intraperitoneal injection of kainic acid (KA). The animals were scarified 30 minutes later. And the changes of CB1lR were detected by immunohistochemistry and Western blot at 4 hours, 1 day, 1 week, 1 month and 2 months post-SE. RESULTS: CB1R in CAl area of hippocampus of SE rats increased gradually at 1 week and then decreased to normal afterward (KA vs NS: 5. 5 ± 1. 1 vs 1.8 ± 0. 2, 6. 4 ± 3. 7 vs 3. 1 ± 0. 7, 16. 9 ± 10. 4 vs 3. 7 ± 1. 7, 8. 8 ± 5. 4 vs 6. 9 ± 4. 0, 3. 2 ± 1. 0 vs 4.4 ± 1. 9). And CBlR in area of CA3, DG had the same trend as CAI. The IA of CBl R significantly increased at 1 week (P <0. 05) and insignificantly deceased after 1 week (P > 0. 05). CONCLUSION: There is a protective increase of CB1R in hippocampus of SE rats and then it returns to normal. Thus CB1R may he involved in the occurrences and terminations of seizures.


Sujet(s)
Hippocampe , État de mal épileptique , Animaux , Cannabinoïdes , Acide kaïnique , Rats , Récepteur cannabinoïde de type CB1 , Crises épileptiques
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