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1.
J Neuroinflammation ; 21(1): 80, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555419

RESUMO

Neuroinflammation is one of the core pathological features of Parkinson's disease (PD). Innate immune cells play a crucial role in the progression of PD. Microglia, the major innate immune cells in the brain, exhibit innate immune memory effects and are recognized as key regulators of neuroinflammatory responses. Persistent modifications of microglia provoked by the first stimuli are pivotal for innate immune memory, resulting in an enhanced or suppressed immune response to second stimuli, which is known as innate immune training and innate immune tolerance, respectively. In this study, LPS was used to establish in vitro and in vivo models of innate immune memory. Microglia-specific Hif-1α knockout mice were further employed to elucidate the regulatory role of HIF-1α in innate immune memory and MPTP-induced PD pathology. Our results showed that different paradigms of LPS could induce innate immune training or tolerance in the nigrostriatal pathway of mice. We found that innate immune tolerance lasting for one month protected the dopaminergic system in PD mice, whereas the effect of innate immune training was limited. Deficiency of HIF-1α in microglia impeded the formation of innate immune memory and exerted protective effects in MPTP-intoxicated mice by suppressing neuroinflammation. Therefore, HIF-1α is essential for microglial innate immune memory and can promote neuroinflammation associated with PD.


Assuntos
Microglia , Doença de Parkinson , Animais , Camundongos , Modelos Animais de Doenças , Neurônios Dopaminérgicos , Hipóxia/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Doenças Neuroinflamatórias , Doença de Parkinson/patologia , Imunidade Treinada
2.
J Neuroinflammation ; 21(1): 153, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849869

RESUMO

Parkinson's disease (PD) is a prevalent neurodegenerative disorder with indistinct etiology and ill-defined pathophysiology. Intestinal inflammation involved in the pathogenesis of PD, but the underlying mechanism is not fully understood. Citrobacter rodentium (C.R) is a gram-negative bacterium that can be used to induce human inflammatory bowel disease in mice. Here, we investigated whether the proinflammatory effects caused by C.R infection initiate PD-like injury and/or exacerbate PD pathology and extensively studied the underlying mechanism. Mice were gavaged once with C.R and monitored for several pathological features at 9 days post infection. The results showed that C.R delivery in mice induced IBD-like symptoms, including significant weight loss, increased fecal water content, an impaired intestinal barrier, intestinal hyperpermeability and inflammation, and intestinal microbiota disturbances. Notably, C.R infection modified dopamine (DA) metabolism in the brains of both male and female mice. Subsequently, a single high dose of MPTP or normal saline was administered at 6 days post infection. At 3 days after MPTP administration, the feces were collected for 16 S rRNA analysis, and PD-like phenotypes and mechanisms were systemically analyzed. Compared with C.R or MPTP injection alone, the injection of C.R and MPTP combined worsened behavioral performance. Moreover, such combination triggered more severe dopaminergic degeneration and glial cell overactivation in the nigrostriatal pathway of mice. Mechanistically, the combination of C.R and MPTP increased the expression of TLR4 and NF-κB p65 in the colon and striatum and upregulated proinflammatory cytokine expression. Therefore, C.R infection-induced intestinal inflammation can impair dopamine metabolism and exacerbate PD pathological processes.


Assuntos
Citrobacter rodentium , Dopamina , Infecções por Enterobacteriaceae , Camundongos Endogâmicos C57BL , Animais , Camundongos , Dopamina/metabolismo , Infecções por Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/patologia , Masculino , Feminino , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/microbiologia , Microbioma Gastrointestinal/fisiologia
3.
FASEB J ; 37(1): e22712, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527439

RESUMO

Mixed lineage leukemia 1 (MLL1), a histone H3 lysine 4 (H3K4) methyltransferase, exerts its enzymatic activity by interacting with menin and other proteins. It is unclear whether inhibition of the MLL1-menin interaction influences epithelial-mesenchymal transition (EMT), renal fibroblast activation, and renal fibrosis. In this study, we investigated the effect of disrupting MLL1-menin interaction on those events and mechanisms involved in a murine model of renal fibrosis induced by unilateral ureteral obstruction (UUO), in cultured mouse proximal tubular cells and renal interstitial fibroblasts. Injury to the kidney increased the expression of MLL1 and menin and H3K4 monomethylation (H3K4me1); MLL1 and menin were expressed in renal epithelial cells and renal interstitial fibroblasts. Inhibition of the MLL1-menin interaction by MI-503 administration or siRNA-mediated silencing of MLL1 attenuated UUO-induced renal fibrosis, and reduced expression of α-smooth muscle actin (α-SMA) and fibronectin. These treatments also inhibited UUO-induced expression of transcription factors Snail and Twist and transforming growth factor ß1 (TGF-ß1) while expression of E-cadherin was preserved. Moreover, treatment with MI-503 and transfection with either MLL siRNA or menin siRNA inhibited TGF-ß1-induced upregulation of α-SMA, fibronectin and Snail, phosphorylation of Smad3 and AKT, and downregulation of E-cadherin in cultured renal epithelial cells. Finally, MI-503 was effective in abrogating serum or TGFß1-induced transformation of renal interstitial fibroblasts to myofibroblasts in vitro. Taken together, these results suggest that targeting disruption of the MLL1-menin interaction attenuates renal fibrosis through inhibition of partial EMT and renal fibroblast activation.


Assuntos
Nefropatias , Leucemia , Obstrução Ureteral , Camundongos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Fibronectinas/metabolismo , Fibrose , Nefropatias/etiologia , Nefropatias/prevenção & controle , Nefropatias/metabolismo , Obstrução Ureteral/metabolismo , Rim/metabolismo , Transição Epitelial-Mesenquimal , Caderinas/metabolismo , RNA Interferente Pequeno/metabolismo
4.
Brain Behav Immun ; 119: 129-145, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38552923

RESUMO

GSDMD-mediated pyroptosis occurs in the nigrostriatal pathway in Parkinson's disease animals, yet the role of GSDMD in neuroinflammation and death of dopaminergic neurons in Parkinson's disease remains elusive. Here, our in vivo and in vitro studies demonstrated that GSDMD, as a pyroptosis executor, contributed to glial reaction and death of dopaminergic neurons across different Parkinson's disease models. The ablation of the Gsdmd attenuated Parkinson's disease damage by reducing dopaminergic neuronal death, microglial activation, and detrimental transformation. Disulfiram, an inhibitor blocking GSDMD pore formation, efficiently curtailed pyroptosis, thereby lessening the pathology of Parkinson's disease. Additionally, a modification in GSDMD was identified in the blood of Parkinson's disease patients in contrast to healthy subjects. Therefore, the detected alteration in GSDMD within the blood of Parkinson's disease patients and the protective impact of disulfiram could be promising for the diagnostic and therapeutic approaches against Parkinson's disease.


Assuntos
Dissulfiram , Neurônios Dopaminérgicos , Microglia , Doença de Parkinson , Proteínas de Ligação a Fosfato , Piroptose , Piroptose/efeitos dos fármacos , Piroptose/fisiologia , Doença de Parkinson/metabolismo , Animais , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Microglia/metabolismo , Microglia/efeitos dos fármacos , Camundongos , Masculino , Humanos , Proteínas de Ligação a Fosfato/metabolismo , Dissulfiram/farmacologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Morte Celular/efeitos dos fármacos , Camundongos Knockout , Gasderminas
5.
Macromol Rapid Commun ; 45(8): e2300699, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38224144

RESUMO

Polymer dielectrics with high dielectric constant are urgently demanded for potential electrical and pulsed power applications. The design of polymers with side chains containing dipolar groups is considered an effective method for preparing materials with a high dielectric constant and low loss. This study synthesizes and comprehensively compare the dielectric properties of novel polyimides with side chains containing urea (BU-PI), carbamate (BC-PI), and sulfonyl (BS-PI) functional groups. The novel polyimides exhibit relatively high dielectric constant and low dielectric loss values due to the enhanced orientational polarization and suppressed dipole-dipole interactions of dipolar groups. In particular, BU-PI containing urea pendant groups presents the highest dielectric constant of 6.14 and reasonably low dielectric loss value of 0.0097. The strong γ transitions with low activation energies derived from dielectric spectroscopy measurements have been further evaluated to demonstrate the enhanced free rotational motion of urea pendant dipoles. In energy storage applications, BU-PI achieves a discharged energy density of 6.92 J cm-3 and a charge-discharge efficiency above 83% at 500 MV m-1. This study demonstrates that urea group, as dipolar pendant group, can provide polymers with better dielectric properties than the most commonly used sulfonyl groups.


Assuntos
Polímeros , Ureia , Polímeros/química , Ureia/química , Imidas/química , Estrutura Molecular , Carbamatos/química , Espectroscopia Dielétrica
6.
Angew Chem Int Ed Engl ; 63(24): e202319766, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598769

RESUMO

High-temperature dielectric polymers are in high demand for powering applications in extreme environments. Here, we have developed high-temperature homopolymer dielectrics with anisotropy by leveraging the hierarchical structure in semicrystalline polymers. The lamellae have been aligned parallel to the surface in the dielectric films. This structural arrangement resembles the horizontal alignment of nanosheet fillers in polymer nanocomposites and nanosheet-like lamellae in block copolymers, which has been proven to provide the optimal topological structure for electrical energy storage. The unique ordering of lamellae in our dielectric films endue a significantly increased breakdown strength and a reduced leakage current compared to amorphous films. This novel approach of enhancing the capacitive energy storage properties by controlled orientation of lamellae in homopolymer offers a new perspective for the design of high-temperature polymer dielectrics.

7.
Macromol Rapid Commun ; 44(2): e2200639, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36125201

RESUMO

Innovative dielectric materials with high-temperature resistance and outstanding dielectric properties have attracted tremendous attention in advanced electronical fields. Polyimide(PI) is considered a promising candidate for the modern electronic industry due to its excellent dielectric properties and comprehensive properties. However, the limited-adjustable range of dielectric constant and the difficulty to obtain a high dielectric constant restrict the application of PI as high dielectric materials. Herein, a novel diamine monomer (2,2'-bis((methylsulfonyl)methyl)-[1,1'-biphenyl]-4,4'-diamine (BSBPA)) containing a rigid biphenyl structure and high dipolar sulfonyl pendant groups is designed for high dielectric polyimides. The rigid biphenyl and polar sulfonyl pendant groups can reasonably optimize the molecular structure and orientational polarization of polyimides to improve their dielectric properties and thermal properties. Moreover, the effect of different bridge linkages on the dielectric properties is studied by using the different dianhydrides. Thus, the PI-BSBPA films especially the DSDA-BSBPA film (DSDA: 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride) achieve great thermal properties (T5%d of 377 °C and Tg of 358 °C) and excellent dielectric properties (6.95 at 1 kHz) along with high discharged energy density of 5.25 J cm-3 and charge-discharge efficiency of 90%. The collaborative control of main-chain and side-chain engineering is effective to endow the polyimides with high-temperature tolerance and high dielectric performance.


Assuntos
Compostos de Bifenilo , Diaminas , Temperatura , Eletrônica
8.
BMC Anesthesiol ; 23(1): 299, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670239

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD) has been reported as a significant complication in elderly patients. Various methods have been proposed for reducing the incidence and severity of POCD. Intravenous lidocaine administration has been reported in the literature to reduce POCD, but the effect of lidocaine remains controversial. METHODS: We screened Medline, Embase, Cochrane Library, and China National Knowledge Infrastructure (up to April 2022) databases following a search strategy for intravenous lidocaine on POCD. We also screened related bibliographies on lidocaine for POCD. Ten articles comprising 1517 patients were selected and analyzed. We divided the postoperative follow-up period as follows: short term (<30 days), medium term (30-90 days), and long term (>90 days). OUTCOMES: We found that lidocaine could attenuate the overall incidence of POCD, especially in the short term. There were no differences between lidocaine and placebo on the overall severity of POCD. CONCLUSION: Lidocaine administered intravenously could attenuate the overall incidence of POCD and its severity in the short term.


Assuntos
Complicações Cognitivas Pós-Operatórias , Idoso , Humanos , Administração Intravenosa , China , Bases de Dados Factuais , Lidocaína
9.
Int J Mol Sci ; 24(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37373121

RESUMO

Histone deacetylase 6 (HDAC6) is involved in the regulation of protein aggregation and neuroinflammation, but its role in Parkinson's disease (PD) remains controversial. In this study, Hdac6-/- mice were generated by CRISPR-Cas9 technology for exploring the effect of HDAC6 on the pathological progression of PD. We found that male Hdac6-/- mice exhibit hyperactivity and certain anxiety. In the acute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice, though motor injury was slightly alleviated by HDAC6 deficiency, dopamine (DA) depletion in the striatum, the decrease in the number of DA neurons in the substantia nigra (SN) and the reduction in DA neuronal terminals were not affected. In addition, activation of glial cells and the expression of α-synuclein, as well as the levels of apoptosis-related proteins in the nigrostriatal pathway, were not changed in MPTP-injected wild-type and Hdac6-/- mice. Therefore, HDAC6 deficiency leads to moderate alterations of behaviors and Parkinson's disease pathology in mice.


Assuntos
Doença de Parkinson , Animais , Masculino , Camundongos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Desacetilase 6 de Histona/genética , Desacetilase 6 de Histona/metabolismo , Camundongos Endogâmicos C57BL , Doença de Parkinson/metabolismo , Substância Negra/metabolismo
10.
Macromol Rapid Commun ; 43(19): e2200218, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35751146

RESUMO

A well-controlled bioenhanced reversible addition-fragmentation chain transfer (RAFT) in the presence of air is carried out by using glucose oxidase (GOx), glucose, ascorbic acid (Asc acid), and ppm level of hemin. The catalytic concentration of hemin is employed to enhance hydrogen peroxide (H2 O2 )/Asc acid redox initiation, achieving rapid RAFT polymerization. Narrow molecular weight distributions and high monomer conversion (Ð as low as 1.09 at >95% conversion) are achieved within tens of minutes. Several kinds of monomers are used to verify the universal implication of the presented method. The influences of the pH and feed ratio of each component on the polymerization rate are assessed. Besides, a polymerization rate regulation is realized by managing Asc acid addition. This work significantly increases the rate of redox-initiated GOx-deoxygen RAFT polymerization by using simple and green reactants, facilitating the application of RAFT polymerization in areas such as biomedical applications.


Assuntos
Glucose Oxidase , Peróxido de Hidrogênio , Ácido Ascórbico , Glucose , Glucose Oxidase/metabolismo , Hemina , Peróxido de Hidrogênio/química , Oxirredução , Polimerização
11.
Macromol Rapid Commun ; 43(1): e2100559, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34713523

RESUMO

An enzyme cascade system including glucose oxidase (GOx) and iron porphyrin (DhHP-6) is encapsulated in a metal-organic framework called zeolitic imidazolate framework-8 (ZIF-8) through one-step facile synthesis. The composite (GOx&DhHP-6@ZIF-8) is then used to initiate oxygen-tolerant reversible addition-fragmentation chain-transfer polymerization for different methacrylate monomers, such as 2-diethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate, and poly(ethylene glycol) methyl ether methacrylate (Mn = 500 g mol-1 ). The composite shows the robustness toward solvent and temperatures, all polymerizations using above monomers and catalyzing by GOx&DhHP-6@ZIF-8 exhibits high monomer conversion (>85%) and narrow molar mass dispersity (<1.3). Besides, acrylic and acrylamide monomers such as 2-hydroxyethyl acrylate and N,N-dimethylacrylamide are also carried to demonstrate the broad applicability. Proton nuclear magnetic resonance characterization and chain extension experiments confirm the retaining end groups of the resultant polymers, which is a significant feature of living polymerization. More importantly, the process of recycling the composite through a centrifuge is simplistic, and the composite still maintains similar activity compared to the original composites after five times. This low-cost and easily separated composite catalyst represents a versatile strategy to synthesize well-defined functional polymers suitable for industrial-scale production.


Assuntos
Biomimética , Oxigênio , Catálise , Polimerização , Polímeros
12.
Phys Chem Chem Phys ; 24(39): 24495-24502, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36193712

RESUMO

The construction of molecules with effective photoinduced intramolecular electron transfer (PET) and energy transfer (ET) processes is critical for the enhancement of the nonlinear optical (NLO) properties. A novel D-π-A type compound, namely tetra (C60)-LaPc, has been constructed from a molecular design perspective, wherein tetra-formyl phthalocyanine is used as a donor, four C60 as acceptors and the phenylacetylene group is introduced into it as π-electron bridge, which can increase the molecular conjugation, reduce the spatial site resistance and expand the coplanarity of the molecule, thus making the intramolecular charge transfer easier. Tetra (C60)-LaPc achieves excellent NLO properties with a giant nonlinear absorption coefficient (45 cm GW-1 and large third-order susceptibility (4.05 × 10-10 esu), which are superior to those of LaPc and C60. In addition to exhibiting a superior nonlinear optical response at 532 nm compared to the single component, tetra (C60)-LaPc also broadens the limiting range to the near-infrared region, showing a significant enhancement of the optical nonlinearity at 1064 nm. This can be attributed to the synergistic effect of the different non-linear absorption mechanisms between C60 and LaPc and the efficient PET process.

13.
J Food Sci Technol ; 59(8): 3043-3052, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35872721

RESUMO

Sanchuan ham is a kind of popular fermented meat product in China. To understand the role of microorganisms in reducing the accumulation of Biogenic amine (BA) during ham fermentation. Biogenic amine oxidase-producing strains were screened and identified using color development method on double-layered plate, oxidase test, high-performance liquid chromatography (HPLC), physiological, biochemical methods, and 16 S rDNA. And then a model for simulated fermentation of Sanchuan ham was developed using the strains as single or mixed starter cultures. The results showed that two biogenic amine oxidase-producing strains were identified as Enterococcus faecium and Enterococcus faecalis from Sanchuan ham by compared to the NCBI database. And the mixed starter cultures showed a more remarkable effect on the decreased production of BA compared to single starter cultures, especially cadaverine and tyramine. The cadaverine was decreased from 92.74 ± 2.44 mg/Kg to 53.95 ± 2.69 mg/Kg and tyramine was decreased from 94.23 ± 3.42 mg/kg to 57.24 ± 3.51 mg/kg in mixed starter cultures than the control group. These results indicate exist biogenic amine oxidase-producing strains could decrease the accumulation of BA in Sanchuan ham. This study reveals important findings for improving the safety and health of Sanchuan ham and other fermented meat products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05419-y.

14.
J Cell Mol Med ; 25(12): 5486-5496, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955654

RESUMO

This study aimed to investigate the molecular mechanisms underlying the role of bone marrow mesenchymal stem cells (BMMSCs)-derived exosomes in ischaemia/reperfusion (IR)-induced damage, and the role of oridonin in the treatment of IR. Exosomes were isolated from BMMSCs. Western blot analysis was done to examine the expression of proteins including CD63, CD8, apoptotic-linked gene product 2 interacting protein X (AliX), Beclin-1, ATG13, B-cell lymphoma-2 (Bcl-2), apoptotic peptidase activating factor 1 (Apaf1) and Bcl2-associated X (Bax) in different treatment groups. Accordingly, the expression of CD63, CD81 and AliX was higher in BMMSCs-EXOs and IR + BMMSCs-EXOs + ORI groups compared with that in the BMMSCs group. And BMMSCs-derived exosomes inhibited the progression of IR-induced myocardial damage, while this protective effect was boosted by the pre-treatment with oridonin. Moreover, Beclin-1, ATG13 and Bcl-2 were significantly down-regulated while Apaf1 and Bax were significantly up-regulated in IR rats. And the presence of BMMSCs-derived exosomes partly alleviated IR-induced dysregulation of these proteins, while the oridonin pre-treatment boosted the effect of these BMMSCs-derived exosomes. The inhibited proliferation and promoted apoptosis of H9c2 cells induced by hypoxia/reperfusion (HR) were mitigated by the administration of BMMSCs-derived exosomes. Meanwhile, HR also induced down-regulation of Beclin-1, ATG13 and Bcl-2 expression and up-regulation of Apaf1 and Bax, which were mitigated by the administration of BMMSCs-derived exosomes. And oridonin pre-treatment boosted the effect of BMMSCs-derived exosomes. In conclusion, our results validated that BMMSCs-derived exosomes suppressed the IR-induced damages by participating in the autophagy process, while the pre-treatment with oridonin could boost the protective effect of BMMSCs-derived exosomes.


Assuntos
Apoptose , Autofagia , Diterpenos do Tipo Caurano/farmacologia , Exossomos/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Traumatismo por Reperfusão Miocárdica/terapia , Animais , Exossomos/efeitos dos fármacos , Masculino , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Sprague-Dawley
15.
FASEB J ; 34(6): 7295-7310, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32281211

RESUMO

Histone deacetylases (HDACs) have been shown to alleviate renal fibrosis, however, the role of individual HDAC isoforms in this process is poorly understood. In this study, we examined the role of HDAC8 in the development of renal fibrosis and partial epithelial-mesenchymal transitions (EMT). In a murine model of renal fibrosis induced by unilateral ureteral obstruction (UUO), HDAC8 was primarily expressed in renal tubular epithelial cells and time-dependently upregulated. This occurred in parallel with the deacetylation of cortactin, a nonhistone substrate of HDAC8, and increased expression of three fibrotic markers: α-smooth muscle actin, collagen 1, and fibronectin. Administration of PCI34051, a highly selective inhibitor of HDAC8, restored acetylation of contactin and reduced expression of those proteins. PCI34051 treatment also reduced the number of renal tubular epithelial cells arrested at the G2/M phase of the cell cycle and suppressed phosphorylation of Smad3, STAT3, ß-catenin, and expression of Snail after ureteral obstruction. In contrast, HDAC8 inhibition reversed UUO-induced downregulation of BMP7 and Klotho, two renoprotective proteins. In cultured murine proximal tubular cells, treatment with PCI34051 or specific HDAC8 siRNA was also effective in inhibiting transforming growth factor ß1 (TGFß1)-induced deacetylation of contactin, EMT, phosphorylation of Smad3, STAT3, and ß-catenin, upregulation of Snail, and downregulation of BMP7 and Klotho. Collectively, these results suggest that HDAC8 activation is required for the EMT and renal fibrogenesis by activation of multiple profibrotic signaling and transcription factors, and suppression of antifibrotic proteins. Therefore, targeting HDAC8 may be novel therapeutic approach for treatment of renal fibrosis.


Assuntos
Fibrose/metabolismo , Histona Desacetilases/metabolismo , Nefropatias/metabolismo , Rim/metabolismo , Acetilação/efeitos dos fármacos , Animais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Fibrose/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Indóis/farmacologia , Rim/efeitos dos fármacos , Nefropatias/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima/efeitos dos fármacos , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo
16.
J Neurooncol ; 151(2): 157-171, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33128099

RESUMO

PURPOSE: Long noncoding RNAs (LncRNAs) are essential epigenetic regulators with critical roles in tumor initiation and malignant progression; however, the mechanism by which aberrantly expressed lncRNA RP11-84E24.3 regulates the pathogenesis of glioma is not fully understood. Here, we investigate the function of lncRNA RP11-84E24.3 in glioma onset and progression as well as identify a molecular pathway regulated by this lncRNA. METHODS: Differentially expressed lncRNAs related to glioma were identified. The aberrant expression of lncRNA RP11-84E24.3 was verified in samples from patients with glioma as well as glioma cell lines. The role of lncRNA RP11-8424.3 in proliferation, apoptosis, migration, and invasion was assessed using gain- and loss-of function approaches, EdU incorporation, flow cytometry, wound healing and Transwell invasion assays. Western blot analysis was utilized to examine the expression of proteins associated with epithelial-to-mesenchymal transition (EMT). The interaction between lncRNA RP11-84E24.3, TFAP2C and SNAI1 was confirmed using RNA pull-down, ChIP and luciferase reporter assays. RESULTS: LncRNA RP11-84E24.3 was up-regulated in both glioma tissues and cell lines. LncRNA RP11-84E24.3 overexpression enhanced the proliferation, migration and invasion of glioma cells while reducing apoptosis. This was associated with a decrease in E-cadherin expression and an increase in N-cadherin and Vimentin expression. LncRNA RP11-84E24.3 directly targeted TFAP2C protein, resulting in increased SNAI1 expression. Knockdown of TFAP2C or SNAI1 reversed the effects of lncRNA RP11-84E24.3 overexpression, while silencing lncRNA RP11-84E24.3 inhibited tumor formation of glioma cells in vivo. CONCLUSIONS: LncRNA RP11-84E24.3 increased SNAI1 expression by forming a complex with TFAP2C protein, promoting EMT in glioma cells and tumor formation.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Transição Epitelial-Mesenquimal , Glioma/patologia , RNA Longo não Codificante/genética , Fatores de Transcrição da Família Snail/metabolismo , Fator de Transcrição AP-2/metabolismo , Adulto , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Humanos , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição da Família Snail/genética , Fator de Transcrição AP-2/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Nanotechnology ; 32(22)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33690190

RESUMO

The development of safe and efficient nanocomposites remains a huge challenge in targeted therapy of glioma. Nanostructured lipid carriers (NLCs), which facilitate specific site drug delivery, have been widely used in glioma treatment. Herein, we aimed to investigate the underlying mechanisms and therapeutic impact of paclitaxel (PTX) and doxorubicin (DOX) loaded NLC (PTX-DOX-NLC) on glioma stem cells (GSCs). To this end, we used a melt-emulsification technique to generate PTX loaded NLC (PTX-NLC), DOX loaded NLC (DOX-NLC), and NLC loaded with both drugs (PTX-DOX-NLC). We firstly confirmed the stability of PTX-DOX-NLC and their ability to gradually release PTX and DOX. Next, we evaluated the effects of PTX-DOX-NLC on apoptosis and proliferation of GSCs by flow cytometry and CellTiter-Glo assay. Besides, the expression of relevant mRNA and proteins was determined by RT-qPCR and Western blot analysis, respectively. Mechanism of action of PTX-DOX-NLC was determined though bioinformatic analysis based on RNA-seq data performed in GSCs derived from different NLC-treated groups. In addition, a mouse xenograft model of glioma was established to evaluate the anti-tumor effects of PTX-DOX-NLCin vivo. Results indicated thar PTX-DOX-NLC showed greater inhibitory effects on proliferation and promotive effects on apoptosis of GSCs compared with PTX-NLC, DOX-NLC, free PTX, and free DOX treatment. Mechanistic investigations evidenced that PTX-DOX-NLC inhibited tumor progression by suppressing the PI3K/AKT/mTOR signalingin vitroandin vivo. Taken together, PTX-DOX-NLC played an inhibitory role in GSC growth, highlighting a potential therapeutic option against glioma.


Assuntos
Glioma , Fosfatidilinositol 3-Quinases , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Doxorrubicina , Portadores de Fármacos , Glioma/tratamento farmacológico , Humanos , Lipídeos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Paclitaxel , Proteínas Proto-Oncogênicas c-akt , Serina-Treonina Quinases TOR
18.
Mol Med ; 26(1): 89, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32957908

RESUMO

BACKGROUND: Hypovolemic shock and septic challenge are two major causes of acute kidney injury (AKI) in the clinic setting. Src homology 2 domain-containing phosphatase 2 (SHP2) is one of the major protein phosphatase tyrosine phosphatase (PTPs), which play a significant role in maintaining immunological homeostasis by regulating many facets of immune cell signaling. In this study, we explored whether SHP2 signaling contributed to development of AKI sequential hemorrhage (Hem) and cecal ligation and puncture (CLP) and whether inactivation of SHP2 through administration of its selective inhibitor, phenylhydrazonopyrazolone sulfonate 1 (PHPS1), attenuated this injury. METHODS: Male C57BL/6 mice were subjected to Hem (a "priming" insult) followed by CLP or sham-Hem plus sham-CLP (S/S) as controls. Samples of blood and kidney were harvested at 24 h post CLP. The expression of neutrophil gelatinase-associated lipocalin (NGAL), high mobility group box 1 (HMGB1), caspase3 as well as SHP2:phospho-SHP2, extracellular-regulated kinase (Erk1/2): phospho-Erk1/2, and signal transducer and activator of transcription 3 (STAT3):phospho-STAT3 protein in kidney tissues were detected by Western blotting. The levels of creatinine (Cre) and blood urea nitrogen (BUN) in serum were measured according to the manufacturer's instructions. Blood inflammatory cytokine/chemokine levels were detected by ELISA. RESULTS: We found that indices of kidney injury, including levels of BUN, Cre and NGAL as well as histopathologic changes, were significantly increased after Hem/CLP in comparison with that in the S/S group. Furthermore, Hem/CLP resulted in elevated serum levels of inflammatory cytokines/chemokines, and induced increased levels of HMGB1, SHP2:phospho-SHP2, Erk1/2:phospho-Erk1/2, and STAT3:phospho-STAT3 protein expression in the kidney. Treatment with PHPS1 markedly attenuated these Hem/CLP-induced changes. CONCLUSIONS: In conclusion, our data indicate that SHP2 inhibition attenuates AKI induced by our double-hit/sequential insult model of Hem/CLP and that this protective action may be attributable to its ability to mitigate activation of the Erk1/2 and STAT3 signaling pathway. We believe this is a potentially important finding with clinical implications warranting further investigation.


Assuntos
Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Benzenossulfonatos/farmacologia , Hidrazonas/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/tratamento farmacológico , Animais , Biomarcadores , Biópsia , Citocinas/metabolismo , Suscetibilidade a Doenças , Hemorragia/complicações , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Sepse/complicações
19.
Small ; 16(22): e2000714, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32378347

RESUMO

High-temperature ceramic/polymer nanocomposites with large energy density as the reinforcement exhibit great potential for energy storage applications in modern electronic and electrical power systems. Yet, a general drawback is that the increased dielectric constant is usually achieved at the cost of decreased breakdown strength, thus leading to moderate improvement of energy density and even displaying a marked deterioration under high temperatures and high electric fields. Herein, a new strategy is reported to simultaneously improve breakdown strength and discharged energy density by a step-by-step, controllable dual crosslinking process, which constructs a strengthened interface as well as reduces molecular chains relaxation under elevated temperatures. Great breakdown strength and discharged energy density is achieved in the dual crosslinked network BT-BCB@DPAES nanocomposites at elevated temperatures when compared to noninterfacial-strengthened, BT/DPAES composites, i.e., an enhanced breakdown strength and a discharged energy density of 442 MV m-1 and 3.1 J cm-3 , increasing by 66% and 162%, and a stable cyclic performance over 10 000 cycles is demonstrated at 150 °C. Moreover, the enhancement through the synergy of two crosslinked networks is rationalized via a comprehensive phase-field model for the composites. This work offers a strategy to enhance the electric storage performances of composites at high temperatures.

20.
FASEB J ; 33(11): 11941-11958, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373855

RESUMO

Disruptor of telomeric silencing-1 like (DOT1L) protein specifically catalyzes the methylation of histone H3 on Lys79 (H3K79) and is implicated in tumors. But its role in tissue fibrosis remains unclear. Here we demonstrated that injury to the kidney increased DOT1L expression and H3K79 dimethylation in renal tubular epithelial cells and myofibroblasts in a murine model of unilateral ureteral obstruction. Administration of EPZ5676, a highly selective inhibitor of DOT1L, attenuated renal fibrosis. Treatment with EPZ5676 or DOT1L small interfering RNA also inhibited TGF-ß1 and serum-induced activation of renal interstitial fibroblasts and epithelial-mesenchymal transition (EMT) in vitro. Moreover, blocking DOT1L abrogated injury-induced epithelial G2/M arrest; reduced expression of Snail, Twist, and Notch1; and inactivated several profibrotic signaling molecules in the injured kidney, including Smad3, epidermal growth factor receptor, platelet-derived growth factor receptor, signal transducer and activator of transcription 3, protein kinase B, and NF-κB. Conversely, DOT1L inhibition increased expression of phosphatase and tensin homolog, a protein associated with dephosphorylation of tyrosine kinase receptors, and prevented decline in levels of Klotho and Smad7, 2 renoprotective factors. Thus, our data indicate that targeting DOT1L attenuates renal fibrosis through inhibition of renal fibroblasts and EMT by suppressing activation of multiple profibrotic signaling pathways while retaining expression of renoprotective factors.-Liu, L., Zou, J., Guan, Y., Zhang, Y., Zhang, W., Zhou, X., Xiong, C., Tolbert, E., Zhao, T. C., Bayliss, G., Zhuang, S. Blocking the histone lysine 79 methyltransferase DOT1L alleviates renal fibrosis through inhibition of renal fibroblast activation and epithelial-mesenchymal transition.


Assuntos
Inibidores Enzimáticos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Rim/efeitos dos fármacos , Animais , Linhagem Celular , Células Cultivadas , Fibroblastos/metabolismo , Fibrose , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/prevenção & controle , Camundongos Endogâmicos C57BL , Interferência de RNA , Ratos , Obstrução Ureteral/metabolismo , Obstrução Ureteral/prevenção & controle
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