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1.
J Biol Chem ; 298(5): 101830, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35300979

RESUMO

Owing to the avascular environment within ovarian follicles, granulosa cells (GCs) are believed to live in a hypoxic niche. Follicle-stimulating hormone (FSH)-mediated steroidogenesis is crucial for normal growth and maturation of ovarian follicles, but it remains unclear how FSH stimulates estradiol (E2) synthesis under hypoxic conditions. Here, we aimed to explore whether FSH affects the ATP production required for estrogen synthesis from the perspective of glucose metabolism. It was observed that the levels of both E2 and HIF-1α were markedly increased in a dose-dependent manner in mouse ovarian GCs after the injection of FSH in vivo, indicating that hypoxia/HIF-1α may be relevant to FSH-induced E2 synthesis. By treating hypoxic GCs with FSH in vitro, we further revealed that the activation of the AMP-activated protein kinase (AMPK)-GLUT1 pathway, which in turn stimulates ATP generation, may be essential for FSH-mediated E2 production during hypoxia. In contrast, inhibition of AMPK or GLUT1 with siRNAs/antagonist both repressed glycolysis, ATP production, and E2 synthesis despite FSH treatment. Moreover, blocking HIF-1α activity using siRNAs/PX-478 suppressed AMPK activation, GLUT1 expression, and E2 levels in FSH-treated GCs. Finally, the in vitro findings were verified in vivo, which showed markedly increased AMPK activity, GLUT1 expression, glycolytic flux, ATP levels, and E2 concentrations in ovarian GCs following FSH injection. Taken together, these findings uncovered a novel mechanism for FSH-regulating E2 synthesis in hypoxic GCs by activating glycolytic metabolism through the HIF-1α-AMPK-GLUT1 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Estradiol , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Estradiol/metabolismo , Estradiol/farmacologia , Feminino , Hormônio Foliculoestimulante/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Glicólise , Células da Granulosa/metabolismo , Hipóxia/metabolismo , Camundongos , Transdução de Sinais
2.
Fish Shellfish Immunol ; 142: 109080, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37748586

RESUMO

NK-lysins are one of the most abundant antimicrobial peptides produced by cytotoxic T lymphocytes (CTLs) and natural killer cells (NKs), and identified as a new class of intrinsically disordered proteins, playing critical roles in the cell-mediated cytotoxicity response, as well as immunomodulatory and antimicrobial activities upon a significant range of pathogens. In the present study, an NK-lysin was identified from Obscure puffer Takifugu obscurus (ToNK-lysin). The open reading frame of ToNK-lysin sequence spans 423 bp, encoding a peptide with 140 amino acids which shares a moderate residue identity (18%-60%) with NK-lysin of mammals and other teleost species. Phylogenetic analysis revealed that ToNK-lysin was most closely related to NK-lysins from the Pleuronectiformes (Bastard halibut Paralichthys olivaceus and Pacific halibut Hippoglossus stenolepis). Comprehensive computational analysis revealed that ToNK-lysin have substantial level of intrinsic disorder, which might be contribute to its multifunction. The transcripts of the ToNK-lysin were detected in multiple examined tissues and most abundant in gills. After bacterial and Poly I:C challenge, the transcriptional levels of ToNK-lysin were significantly up-regulated in the head kidney, liver and spleen at different time points. The recombinant ToNK-lysin showed significant antibacterial activity against Vibrio harveyi and Escherichia coli, and the ToNK-lysin treatment not only reduced the bacterial loads in liver and head kidney, but also alleviated the pathogen-mediated upregulation of immune-related genes. In addition, the co-incubation with rToNK-lysin protein remarkably degraded bacterial genomic DNA, suggesting the potential mechanism of ToNK-lysin against microbes. These results suggest that ToNK-lysin possess antibacterial and immunoregulatory function both in vivo and in vitro, which may allow it a potential applicability to the aquaculture industry.


Assuntos
Antibacterianos , Tetraodontiformes , Animais , Sequência de Aminoácidos , Filogenia , Antibacterianos/farmacologia , Adjuvantes Imunológicos , Fatores Imunológicos/farmacologia , Proteolipídeos/genética , Mamíferos/metabolismo
3.
Bioorg Med Chem Lett ; 28(8): 1381-1385, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29555153

RESUMO

The approach of tethering together two known receptor ligands, to be used as molecular probes for the study of G protein-coupled receptor (GPCR) systems, has proven to be a valuable approach. Selective ligands that possess functionality that can be used to link to other ligands, are useful in the development of novel antagonists and agonists. Such molecules can also be attached to reporter molecules, such as fluorophores, for the study of GPCR dimerization and its role in signaling. The highly selective serotonin (5-HT) 5-HT2A receptor (5-HT2AR) antagonist M100907 (volinanserin) is of clinical interest in the treatment of neurological and mental health disorders. Here, we synthesized the most active (+)-M100907 enantiomer as well as a series of derivatives that possessed either an alkyne or an azide. The triazole resulting from the dipolar cycloaddition of these groups did not interfere with the ability of the bivalent ligand to act as an antagonist. Thus, we have synthesized a number of compounds which will prove useful in elucidating the role of the 5-HT2AR in the central nervous system.


Assuntos
Fluorbenzenos/farmacologia , Piperidinas/farmacologia , Receptor 5-HT2A de Serotonina/metabolismo , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Alcinos/síntese química , Alcinos/química , Alcinos/farmacologia , Animais , Azidas/síntese química , Azidas/química , Azidas/farmacologia , Células CHO , Cálcio/metabolismo , Cricetulus , Fluorbenzenos/síntese química , Fluorbenzenos/química , Piperidinas/síntese química , Piperidinas/química , Antagonistas do Receptor 5-HT2 de Serotonina/síntese química , Antagonistas do Receptor 5-HT2 de Serotonina/química , Estereoisomerismo
4.
Front Med (Lausanne) ; 10: 1199146, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441689

RESUMO

Chimeric antigen receptor (CAR) T-cell therapies have evolved as breakthrough treatment options for the management of hematological malignancies and are also being developed as therapeutics for solid tumors. However, despite the impressive patient responses from CD19-directed CAR T-cell therapies, ~ 40%-60% of these patients' cancers eventually relapse, with variable prognosis. Such relapses may occur due to a combination of molecular resistance mechanisms, including antigen loss or mutations, T-cell exhaustion, and progression of the immunosuppressive tumor microenvironment. This class of therapeutics is also associated with certain unique toxicities, such as cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, and other "on-target, off-tumor" toxicities, as well as anaphylactic effects. Furthermore, manufacturing limitations and challenges associated with solid tumor infiltration have delayed extensive applications. The molecular imaging modalities of immunological positron emission tomography and single-photon emission computed tomography (immuno-PET/-SPECT) offer a target-specific and highly sensitive, quantitative, non-invasive platform for longitudinal detection of dynamic variations in target antigen expression in the body. Leveraging these imaging strategies as guidance tools for use with CAR T-cell therapies may enable the timely identification of resistance mechanisms and/or toxic events when they occur, permitting effective therapeutic interventions. In addition, the utilization of these approaches in tracking the CAR T-cell pharmacokinetics during product development and optimization may help to assess their efficacy and accordingly to predict treatment outcomes. In this review, we focus on current challenges and potential opportunities in the application of immuno-PET/-SPECT imaging strategies to address the challenges encountered with CAR T-cell therapies.

5.
J Inorg Biochem ; 202: 110857, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669695

RESUMO

Thirteen novel palladium(II) complexes of the general formula [Pd(bipy)(O,O'-dkt)](PF6), (where bipy is 2,2'-bipyridine and O,O'-dkt is ß-diketonate ligand hispolon or its derivative) have been prepared through a metal-ligand coordination method that involves spontaneous formation of the corresponding diketonate scaffold. The obtained palladium(II) complexes have been characterized by NMR spectroscopy, ESI-mass spectrometry as well as elemental analysis. The cytotoxicity analysis indicates that most of the obtained palladium(II) complexes show promising growth inhibition in three human cancer cell lines. Flow cytometry analysis shows complex 3e could promote intracellular reactive oxygen species (ROS) accumulation and lead cancer cell death. And the suppression of ROS accumulation and the rescue of cell viability in HeLa cells by N-acetyl-L-cysteine (NAC) suggest the possible link between the increase in ROS generation and cytotoxicity of complex 3e. Flow cytometry analysis also reveal that complex 3e cause cell cycle arrest in the G2/M phase and collapse of the mitochondrial membrane potential, promote the generation of ROS and lead to tumor cell apoptosis. The interactions of complex 3e with calf thymus DNA (CT-DNA) have been evaluated by UV-Vis spectroscopy, fluorescence quenching experiments and viscosity measurements, which reveal that the complex interact with CT-DNA through minor groove binding and/or electrostatic interactions. Further, the results of fluorescence titration and site marker competitive experiment on bovine serum albumin (BSA) suggest that complex 3e can quench the fluorescence of BSA via a static quenching process and bind to BSA in Sudlow's site II.


Assuntos
Antineoplásicos , Apoptose/efeitos dos fármacos , Catecóis , Complexos de Coordenação , DNA/química , Paládio , Soroalbumina Bovina/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Catecóis/química , Catecóis/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HeLa , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Paládio/química , Paládio/farmacologia
6.
Colloids Surf B Biointerfaces ; 184: 110525, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585307

RESUMO

The purpose of this paper was to fabricate a novel methoxy poly(ethylene glycol)-block-poly(caprolactone)-block-poly(1, 4, 8-Trioxa [4.6] spiro-9-undecanone) (mPEG-b-PCL-b-PTOSUO, mPECT) triblock copolymer and study on the in vitro anti-tumor activity of curcumin-loaded mPECT nanoparticles (NPs). The mPEG-b-PCL-b-PTOSUO NPs were fabricated with solvent evaporation. Transmission electron microscope (TEM) and laser particle analyzer were applied to investigate the morphology and size distribution of the obtained mPECT NPs. The cytotoxicity of the copolymer (mPECT) was reflected by cell viability. Curcumin (CUR), as a model drug, was encapsulated into mPECT NPs. The in vitro anti-tumor activity of CUR-loaded mPECT NPs were also studied. 1H nuclear magnetic resonance (1H NMR), Raman, and Fourier transform infrared spectroscopy (FTIR) spectra confirmed the obtaining of mPECT. TEM photograph showed that most of mPECT NPs were in spherical shapes with a uniform size distribution. High cell viability suggested that the cargo-free mPECT NPs had no obvious cytotoxicity. Fluorescent photographs illustrated that CUR-loaded mPECT NPs could be up-taken by SW1990 cells. The medicated NPs could inhibit the proliferation of SW1990 cells. Therefore, the mPECT NPs could be used as a vehicle to improve the bioavailability and anti-tumor effects of CUR.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Nanopartículas/química , Poliésteres/farmacologia , Polietilenoglicóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Curcumina/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Estrutura Molecular , Tamanho da Partícula , Poliésteres/química , Polietilenoglicóis/química , Propriedades de Superfície , Células Tumorais Cultivadas
7.
Mater Sci Eng C Mater Biol Appl ; 76: 975-984, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28482615

RESUMO

To enhance the therapeutic effects of meloxicam (MLX), we developed an oral MLX-loaded poly(ethylene glycol)-b-poly(ε-caprolactone) nanoparticles@hydrogel (MLX-NPs@hydrogel) preparation. The MLX-NPs were fabricated via a solvent evaporation method, and their morphologies were observed by a JEM-1011 transmission electron microscope (TEM). The poly(mPEGMA-co-MAA) hydrogels were synthesized, and studies on their pH sensibilities were carried out in pH1.2, 6.8, and 7.4 buffers. The final MLX-NPs@hydrogel preparation was obtained by immersing the hydrogels in the MLX-NPs suspensions (pH7.4) for 48h. The thermodynamic properties and cytotoxicity of the MLX-NPs@hydrogel preparation were also studied. TEM images illustrated that mPEG-b-PCL NPs had a uniform size distribution. The poly(mPEGMA-co-MAA) hydrogels showed an excellent pH-sensibility. Thermal gravity analysis (TGA) data suggested that the protection of hydrogels improved the stability of mPEG-b-PCL NPs. The release studies revealed that MLX-NPs@hydrogel could deliver the MLX-NPs into alkalescent environment (e.g. intestinal tract). Then, the medicated NPs released MLX at a sustained release profile. Such preparation could overcome the drawbacks of oral MLX, and enhance its therapeutic effects. Therefore, the NPs@hydrogel was a promising sustained-controlled release matrix.


Assuntos
Nanopartículas , Etilenoglicóis , Hidrogéis , Meloxicam , Poliésteres , Polietilenoglicóis , Tiazinas , Tiazóis
8.
Biotechnol Prog ; 32(1): 208-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26400046

RESUMO

Potato residue is vastly produced in the food industry but it is landfilled. This article describes the treatment of purified cellulose derived from potato residues by a high pressure homogenizer to produce nano-fibrillated cellulose (NFC), which was then oxidized by sodium periodate to prepare dialdehyde nano-fibrillated cellulose (DANFC). The produced NFC and DANFC were characterized by a scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The orthogonal experiment was induced to obtain the maximum degree of oxidation (DO) on DANFC. The results indicated that the optimal conditions were 40°C and pH 3. Alternatively, the isotherm and kinetic studies for the adsorption of creatinine on DANFC with different DOs (70.5 and 88.8%) were investigated, and the experimental results fitted well into Freundlich isotherm model and pseudo second-order kinetic model. The maximum adsorption capacities of DANFCs with the DO of 70.55 and 88.85% were 6.7 and 17.2 mg g(-1) , respectively, which were achieved under the conditions of 37°C and initial creatinine concentration of 100 mg L(-1).


Assuntos
Celulose/análogos & derivados , Creatinina/química , Nanofibras/química , Solanum tuberosum/química , Adsorção , Celulose/síntese química , Celulose/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
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