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1.
Molecules ; 29(5)2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38474637

RESUMO

Based on the reported research, hydroxyl radicals can be rapidly transformed into carbonate radicals in the carbonate-bicarbonate buffering system in vivo. Many of the processes considered to be initiated by hydroxyl radicals may be caused by carbonate radicals, which indicates that lipid peroxidation initiated by hydroxyl radicals can also be caused by carbonate radicals. To date, theoretical research on reactions of hydrogen abstraction from and radical addition to polyunsaturated fatty acids (PUFAs) of carbonate radicals has not been carried out systematically. This paper employs (3Z,6Z)-nona-3,6-diene (NDE) as a model for polyunsaturated fatty acids (PUFAs). Density functional theory (DFT) with the CAM-B3LYP method at the 6-311+g(d,p) level was used to calculate the differences in reactivity of carbonate radicals abstracting hydrogen from different positions of NDE and their addition to the double bonds of NDE under lipid solvent conditions with a dielectric constant of 4.0 (CPCM model). Grimme's empirical dispersion correction was taken into account through the D3 scheme. The energy barrier, reaction rate constants, internal energy, enthalpy and Gibbs free energy changes in these reactions were calculated With zero-point vibrational energy (ZPVE) corrections. The results indicated that carbonate radicals initiate lipid peroxidation primarily through hydrogen abstraction from diallyl carbon atoms. The reaction of hydrogen abstraction from diallyl carbon atoms exhibits the highest reaction rate, with a reaction rate constant approximately 43-fold greater than the second-ranked hydrogen abstraction from allyl carbon atoms. This process has the lowest energy barrier, internal energy, enthalpy, and Gibbs free energy changes, indicating that it is also the most spontaneous process.


Assuntos
Ácidos Graxos Insaturados , Hidrogênio , Peroxidação de Lipídeos , Hidrogênio/química , Ácidos Graxos Insaturados/química , Carbonatos , Radical Hidroxila/química , Carbono , Radicais Livres/química
2.
Opt Express ; 31(1): 344-354, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606971

RESUMO

In this paper, an efficient discontinuous Galerkin time-domain (DGTD) method is proposed to solve Maxwell's equations for nonlinear Kerr or Raman media. Based on our previous work, an arbitrary high-order derivatives DGTD method with a local time-stepping scheme is introduced for simulating dynamic optical responses in nonlinear dispersive media such that the nonlinear effects do not impose constraints on the stability conditions for linear subdomains. Therefore, the scheme enables the simulations in the nonlinear and linear media regions with independent time-stepping increments, which greatly improves the efficiency of the time-domain analysis. Moreover, by applying an iteration solution scheme, the proposed method preserves the intrinsic local features, which is favorable for the realization of highly parallelized algorithms. Numerical examples demonstrate the accuracy and the efficiency of our proposed method. We believe the proposed method provides an effective tool for numerical analysis of nonlinear optical phenomena.

3.
Int J Mol Sci ; 23(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36233293

RESUMO

Thyroid cancer remains the most common endocrine malignancy worldwide, and its incidence has steadily increased over the past four years. Papillary Thyroid Cancer (PTC) is the most common differentiated thyroid cancer, accounting for 80-85% of all thyroid cancers. Mitochondrial proteins (MRPs) are an important part of the structural and functional integrity of the mitochondrial ribosomal complex. It has been reported that MRPL9 is highly expressed in liver cancer and promotes cell proliferation and migration, but it has not been reported in PTC. In the present study we found that MRPL9 was highly expressed in PTC tissues and cell lines, and lentivirus-mediated overexpression of MRPL9 promoted the proliferation and migration ability of PTC cells, whereas knockdown of MRPL9 had the opposite effect. The interaction between MRPL9 and GGCT (γ-glutamylcyclotransferase) was found by immunofluorescence and co-immunoprecipitation experiments (Co-IP). In addition, GGCT is highly expressed in PTC tissues and cell lines, and knockdown of GGCT/MRPL9 in vivo inhibited the growth of subcutaneous xenografts in nude mice and inhibited the formation of lung metastases. Mechanistically, we found that knockdown of GGCT/MRPL9 inhibited the MAPK/ERK signaling pathway. In conclusion, our study found that the interaction of GGCT and MRPL9 modulates the MAPK/ERK pathway, affecting the proliferation and migration of PTC cells. Therefore, GGCT/MRPL9 may serve as a potential biomarker for PTC monitoring and PTC treatment.


Assuntos
Sistema de Sinalização das MAP Quinases , Neoplasias da Glândula Tireoide , gama-Glutamilciclotransferase , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , gama-Glutamilciclotransferase/genética
4.
Zhongguo Zhong Yao Za Zhi ; 46(5): 1155-1159, 2021 Mar.
Artigo em Zh | MEDLINE | ID: mdl-33787110

RESUMO

Chemical constituents of water extracts of Asplenium ruprechtii were investigated. Five compounds were isolated by silica gel, Sephadex LH-20 gel column chromatographies and preparative HPLC, and their structures were identified by various spectral analyses as aspleniumside G(1), trans-p-coumaric acid(2), trans-p-coumaric acid 4-O-ß-D-glucoside(3), cis-p-coumaric acid 4-O-ß-D-glucoside(4), and(E)-ferulic acid-4-O-ß-D-glucoside(5). Among them, compound 1 is a new 9,19-cycloartane glycoside.


Assuntos
Glicosídeos , Triterpenos , Cromatografia Líquida de Alta Pressão , Glucosídeos
5.
J Cell Biochem ; 121(5-6): 3392-3405, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31904151

RESUMO

Although many methods and new therapeutic drugs have been developed, the overall survival rate and long-term survival rate of patients with gastric cancer (GC) are still not satisfactory. In this study, we investigated the effects of microRNA miR-133a-3p and transcription factor FOXP3 on proliferation and autophagy of GC cells and their interactions. Our results showed that knockdown of FOXP3 increased the proliferation and autophagy of GC cells. The relationship between FOXP3 and autophagy has not been reported previously. In addition, FOXP3 could directly bind the promoter region of TP53 and inhibit its expression. miR-133a-3p increased the proliferation and autophagy via decreasing the protein level of FOXP3 by targeting its 3'-UTR. Our research provides new insights into the development of GC and provides new ideas and theoretical basis for the clinical treatment of GC and the development of new drug targets.


Assuntos
Autofagia , Proliferação de Células , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Gástricas/metabolismo , Regiões 3' não Traduzidas , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Citoplasma/metabolismo , Humanos , Regiões Promotoras Genéticas
6.
Cell Commun Signal ; 18(1): 107, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32646440

RESUMO

BACKGROUND: Foxp3+CD4+ regulatory T cells (Treg) constitutes a key event in autoimmune diseases. STAT5b is the critical link between the IL-2/15 and FOXP3, the master regulator of Treg cells. METHODS: The CD3+T cell and Foxp3+CD4+ regulatory T cells were overexpressioned or knockdown MKL-1 and STAT5a and tested for Treg cell development and function. Direct interaction of MKL-1 and STAT5a were analyzed by coimmunoprecipitation assays, Luciferase assay, Immunofluoresence Staining and Yeast two-hybrid screening. The effect of MKL-1 and STAT5a on the Treg genes expression was analyzed by qPCR and western blotting and Flow cytometry. RESULTS: However, the molecular mechanisms mediating STAT5b-dependent Treg genes expression and Treg cell phenotype and function in autoimmune diseases are not well defined. Here, we report that the MKL-1 is a coactivator for the major Treg genes transcription factor STAT5b, which is required for human Treg cell phenotype and function. The N terminus of STAT5b, which contains a basic coiled-coil protein-protein interaction domain, binds the C-terminal activation domain of MKL-1 and enhances MKL-1 mediated transcriptional activation of Treg-specific, CArG containing promoters, including the Treg-specific genes Foxp3. Suppression of endogenous STAT5b expression by specific small interfering RNA attenuates MKL-1 transcriptional activation in cultured human cells. The STAT5b-MKL-1 interaction identifies a role of Treg-specific gene regulation and regulated mouse Treg cell development and function and suggests a possible mechanism for the protective effects of autoimmune disease Idiopathic Thrombocytopenic Purpura (ITP). CONCLUSIONS: Our studies demonstrate for the first time that MKL-1 is a coactivator for STAT5b, the regulator of Treg cell development and function. Video abstract.


Assuntos
Fator de Transcrição STAT5/metabolismo , Linfócitos T Reguladores/imunologia , Transativadores/metabolismo , Amidas/farmacologia , Sequência de Bases , Biomarcadores/metabolismo , Complexo CD3/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Humanos , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Janus Quinase 3/metabolismo , Contagem de Linfócitos , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Púrpura Trombocitopênica Idiopática/imunologia , Piridinas/farmacologia , Fator de Transcrição STAT5/química , Fator de Resposta Sérica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transativadores/química , Tirfostinas/farmacologia , Proteína rhoA de Ligação ao GTP/metabolismo
7.
Bioorg Chem ; 102: 104085, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32688113

RESUMO

Five new cycloartane glycosides, named aspleniumside A - E, were discovered and characterized by re-investigated the remaining extracts of the whole plant of Asplenium ruprechtii Sa. Kurata, a famous folk medicine for treating thromboangitis obliterans in China, Japan, and Korea. Compounds 3-5 possessed the 9,19-seco-cycloartane-9,11-en triterpene aglycone with 3,7(or 23),24,25,30-highly oxidized methylene, methylene or quaternary carbons, that was found in this species for the first time. The stereo-chemistry of all new compounds were fully discussed by extensive analysis of the 1D and 2D NMR data, and comparisons with those data of known compounds. 24R configuration was determined here which indicated the different growing areas of the same species could influence the secondary metabolic behavior, leading to the differences in chemical composition. All glycoside groups were determined as ß-d-glucopyranosyl by 1H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with d-glucose. All the cycloartane glycosides were evaluated against HL-60 and HepG2 cells for cytotoxicity, compounds 1-3, showed potential cytotoxicity with the IC50 in range of 18-60 µM, while the standard sorafenib showed IC50 value of 10.61 ± 0.43 and 13.43 ± 1.12 µM against HL-60 and HepG2, respectively. The results attained in this study indicated that cycloartane glycosides should be the cytotoxicity substance in A. ruprechtii Sa. Kurata, and had the potential to be developed as tumor cytotoxicity agent applied in clinic.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Gleiquênias/química , Glicosídeos/farmacologia , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/isolamento & purificação , Células HL-60 , Células Hep G2 , Humanos , Conformação Molecular , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
8.
Chem Biodivers ; 17(12): e2000500, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078897

RESUMO

We characterized a new cycloartane glycoside, herein known as aspleniumside F (1), along with five known compounds as kaempferol-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-galacopyranoside (2), quercetin-3-O-[(6-O-(E)-feruloyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (3), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranoside (4), kaempferol-3-O-[(6-O-(E)-caffeoyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (5), and kaempferol-3-O-[(6-O-p-coumaroyl)-ß-D-glucopyranosyl]-(1→2)-ß-D-glucopyranosyl-7-O-ß-D-glucopyranoside (6), from Asplenium ruprechtii Sa. Kurata, a folk medicine widely used to treat Thromboangiitis obliterans in China, Japan, and Korea. Based on spectroscopic, mainly 1D-, 2D-NMR and (+)-HR-ESI-MS, analyses as well as through comparisons with previous reports, its chemical structure was determined as 3ß,24,30-tri-ß-D-glucopyranosyl-23,25-dihydroxycycloartane (= (23R,24R)-3ß,24-bis-(ß-D-glucopyranosyloxy)-23,25-dihydroxy-9ß-9,19-cyclolanostan-29-yl ß-D-glucopyranoside). According to the 1 H coupling constant of anomeric protons and co-TLC of the acid hydrolysate with D-glucose, all three glycoside groups in 1 were revealed as ß-D-glucopyranosyl. Furthermore, SOD-like antioxidant activity evaluation via IC50 of 12.43, 6.78, 9.12, 6.94 and 4.85 µM revealed that compounds 2-6 had bioactivity.


Assuntos
Glicosídeos/química , Traqueófitas/química , Triterpenos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética
9.
J Cell Biochem ; 120(5): 7814-7824, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30426547

RESUMO

Megakaryoblastic leukemia 1 (MKL1) was closely related to the pathogenesis of various human malignant cancers. MiR34a was reported to be closely related to cancer cell proliferation. Forkhead box protein 3 (FOXP3) was a transcription factor that played a different role in different cancer types. CDK6 was involved in cell cycle progression and was upregulated in several types of cancers. The present study investigated the effects of MKL1/miR34a/FOXP3 axis on cell proliferation in MGC803 gastric cancer cells. Our results demonstrated that overexpression of MKL1 promoted proliferation of MGC80-3 cells, MKL1 directly binding to the promoter of CDK6 to increase its expression. Knockdown of FOXP3 promoted proliferation of MGC80-3 cells and MKL1 inhibited the expression of FOXP3 via miR-34a. The finding can contribute to elucidating the regulatory mechanism involved in the cell cycle progression of gastric cancer cells and may aid in screening potential gene targets for the biological therapy of gastric cancer.

10.
Cell Commun Signal ; 17(1): 93, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409371

RESUMO

BACKGROUND: Breast cancer is the leading cause of cancer death in women worldwide which is closely related to metastasis. But the exact molecular mechanism of ERα-36 and STAT3 on metastasis is still not fully understood. METHODS: MCF-7 and MDA-MB-231 human breast cancer cell lines and MCF-10A were overexpressioned or knockdown ERα-36 and STAT3 and tested for migration, invasion and proliferation assays. Direct interaction of STAT3 and ERα-36 were analyzed by coimmunoprecipitation assays. The effect of STAT3 and ERα-36 on MMP2/9 expression was analyzed by qPCR and western blotting. STAT3 phospholyation and acetylation by ERα-36 and p300 were observed and quantified by coimmunoprecipitation assays and western blotting. RESULTS: Cross-talk between ERα-36 and STAT3 was demonstrated to mediate through a direct physical association between the two proteins. Furthermore, the interaction between ERα-36 and STAT3 was demonstrated to give rise to functional changes in their signaling events. Both MMP2 and MMP9 expression require the binding of the newly identified protein complex, ERα-36-STAT3, to its promoter, the second phase, which is more robust, depends on ERα-mediated recruitment of p300 onto the complex and the subsequent acetylation of STAT3. In addition, STAT3 is tyrosine-phosphorylated in a biphasic manner, and the late phase requires ERα-36-mediated p300-dependent acetylation. Furthermore, interference with acetylation of STAT3 by overexpression of acetylation null STAT3 mutant led to the loss of MMP2 and MMP9 expression. ChIP analysis and reporter gene assays revealed that ERα-36-STAT3 complex binding to the MMP2 and MMP9 promoter led to an enhanceosome formation and facilitated MMP2 and MMP9 expression. CONCLUSIONS: Our studies demonstrate for the first time that the function of MMP2 and MMP9 in breast cancer cell migration, which is mediated by interactions between ERα-36 and STAT3.


Assuntos
Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Células MCF-7 , Mutação , Fator de Transcrição STAT3/genética , Transdução de Sinais
11.
J Biol Chem ; 291(1): 89-102, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26565029

RESUMO

The BCL-2 protein family plays a critical role in regulating cellular commitment to mitochondrial apoptosis. Pro-apoptotic Bcl-2-associated X protein (BAX) is an executioner protein of the BCL-2 family that represents the gateway to mitochondrial apoptosis. Following cellular stresses that induce apoptosis, cytosolic BAX is activated and translocates to the mitochondria, where it inserts into the mitochondrial outer membrane to form a toxic pore. How the BAX activation pathway proceeds and how this may be inhibited is not yet completely understood. Here we describe synthetic antibody fragments (Fabs) as structural and biochemical probes to investigate the potential mechanisms of BAX regulation. These synthetic Fabs bind with high affinity to BAX and inhibit its activation by the BH3-only protein tBID (truncated Bcl2 interacting protein) in assays using liposomal membranes. Inhibition of BAX by a representative Fab, 3G11, prevented mitochondrial translocation of BAX and BAX-mediated cytochrome c release. Using NMR and hydrogen-deuterium exchange mass spectrometry, we showed that 3G11 forms a stoichiometric and stable complex without inducing a significant conformational change on monomeric and inactive BAX. We identified that the Fab-binding site on BAX involves residues of helices α1/α6 and the α1-α2 loop. Therefore, the inhibitory binding surface of 3G11 overlaps with the N-terminal activation site of BAX, suggesting a novel mechanism of BAX inhibition through direct binding to the BAX N-terminal activation site. The synthetic Fabs reported here reveal, as probes, novel mechanistic insights into BAX inhibition and provide a blueprint for developing inhibitors of BAX activation.


Assuntos
Anticorpos/farmacologia , Proteína X Associada a bcl-2/antagonistas & inibidores , Proteína X Associada a bcl-2/química , Sequência de Aminoácidos , Apoptose/efeitos dos fármacos , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Sítios de Ligação , Citocromos c/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Lipossomos/metabolismo , Espectroscopia de Ressonância Magnética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Permeabilidade/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
12.
Water Sci Technol ; 75(11-12): 2622-2630, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28617282

RESUMO

In this study, we investigate the rejection of Hg, Cd, and Pb and the effect of coexisting metals on Hg removal through forward osmosis (FO) and membrane distillation (MD) in order to establish a more effective water treatment process. The results of our laboratory experiment indicate that more than 97% of the rejection for each metal is achieved through the FO system, and this rejection is the highest among previous studies using membrane filtrations. Moreover, we examine the matrix effect of the coexisting Cd and Pb on the rejection of Hg in the FO system. Hg2+ rejection increases with increase in the concentration of the coexisting metals. Furthermore, we study the effect of the Hg concentration and the water temperature on rejection of Hg2+. Indeed, the rejection of Hg2+ is achieved above 95% under any condition. However, approximately 1-10 ppb Hg from the feed solution remains in the draw solution due to permeation. Therefore, we use a FO-MD hybrid system. Approximately 100% rejection of Hg2+ and a stable water flux are achieved. Thus, the FO-MD hybrid system is considered an important alternative to previous studies using membrane filtration for heavy metals removal.


Assuntos
Destilação/métodos , Osmose , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Cádmio/química , Chumbo/química , Membranas Artificiais , Mercúrio/química
13.
Biochemistry ; 54(8): 1589-99, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25658332

RESUMO

Fusion of host and viral membranes is a critical step during infection by membrane-bound viruses. The HIV-1 glycoproteins gp120 (surface subunit) and gp41 (fusion subunit) represent the prototypic system for studying this process; in the prevailing model, the gp41 ectodomain forms a trimeric six-helix bundle that constitutes a critical intermediate and provides the energetic driving force for overcoming barriers associated with membrane fusion. However, most structural studies of gp41 variants have been performed either on ectodomain constructs lacking one or more of the membrane-associated segments (the fusion peptide, FP, the membrane-proximal external region, MPER, and the transmembrane domain, TM) or on variants consisting of these isolated segments alone without the ectodomain. Several recent reports have suggested that the HIV-1 ectodomain, as well as larger construct containing the membrane-bound segments, dissociates from a trimer to a monomer in detergent micelles. Here we compare the properties of a series of gp41 variants to delineate the roles of the ectodomain, FP, and MPER and TM, all in membrane-mimicking environments. We find that these proteins are prone to formation of a monomer in detergent micelles. In one case, we observed exclusive monomer formation at pH 4 but conditional trimerization at pH 7 even at low micromolar (∼5 µM) protein concentrations. Liposome release assays demonstrate that these gp41-related proteins have the capacity to induce content leakage but that this activity is also strongly modulated by pH with much higher activity at pH 4. Circular dichroism, nuclear magnetic resonance, and binding assays with antibodies specific to the MPER provide insight into the structural and functional roles of the FP, MPER, and TM and their effect on structure within the larger context of the fusion subunit.


Assuntos
Proteína gp41 do Envelope de HIV/química , HIV-1/química , Multimerização Proteica , Membrana Celular/química , Membrana Celular/genética , Membrana Celular/metabolismo , Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/metabolismo , HIV-1/genética , HIV-1/metabolismo , Concentração de Íons de Hidrogênio , Micelas , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
14.
Psychol Res Behav Manag ; 17: 379-392, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38317739

RESUMO

Purpose: While previous research has highlighted the influence of family, school, and peer factors on smartphone addiction and sleep quality, the cumulative effects of these risk factors and their underlying causal relationships remain poorly understood. Therefore, based on the cumulative risk model and the bioecological model of human development, this study examined the longitudinal associations between cumulative ecological risk and smartphone addiction and sleep quality. Methods: A survey was conducted among 653 Chinese university freshmen (mean age 18.56) at two distinct time points, with a 6-month interval. The initial assessment focused on family, school, and peer risk factors, while the subsequent assessment focused on smartphone addiction and sleep quality. Results: Approximately 63.71% of university freshmen were found to be at risk of exposure. Compared to other risk-exposure groups, the group with no-risk exposure exhibited the lowest scores for smartphone addiction and sleep quality. The relationships between cumulative ecological risk and smartphone addiction and sleep quality displayed a linear pattern and a discernible "gradient effect". Smartphone addiction was identified as a fully mediating factor in the link between cumulative ecological risk and sleep quality, with a mediating effect value of 0.08 (representing 44.44% of the total effect). Conclusion: University freshmen face various risks associated with their families, schools, and peers. The cumulative ecological risk can, directly and indirectly, impact sleep quality by influencing smartphone addiction. Given the observed "gradient effect" of cumulative ecological risk on smartphone addiction and sleep quality, it is imperative to adopt comprehensive risk prevention strategies to mitigate the impact of each risk factor.

15.
Microbiol Spectr ; 12(1): e0188223, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38014983

RESUMO

IMPORTANCE: Phage therapy is gaining traction as an alternative to antibiotics due to the rise of multi-drug-resistant (MDR) bacteria. This study assessed the pharmacokinetics and safety of PA_LZ7, a phage targeting MDR Pseudomonas aeruginosa, in mice. After intravenous administration, the phage showed an exponential decay in plasma and its concentration dropped significantly within 24 h for all dosage groups. Although there was a temporary increase in certain plasma cytokines and spleen weight at higher dosages, no significant toxicity was observed. Therefore, PA_LZ7 shows potential as an effective and safe candidate for future phage therapy against MDR P. aeruginosa infections.


Assuntos
Bacteriófagos , Infecções por Pseudomonas , Fagos de Pseudomonas , Animais , Camundongos , Fagos de Pseudomonas/genética , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Infecções por Pseudomonas/terapia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa
16.
Int J Biol Sci ; 19(14): 4457-4475, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781038

RESUMO

Chemotherapy is a standard method in traditional treatment for gastric cancer. It is well known that the anti-tumor effects of chemotherapy are achieved mainly through the direct killing of cancer cells via apoptosis. However, chemotherapy often fails due to drug resistance. Therefore, non-apoptotic cell death induction by ferroptosis has recently been proposed as a new therapeutic modality to ablate cancer. In this study, we determined the role of MKL-1 in ferroptosis. In vitro and in vivo experiments showed that inhibition of MKL-1 expression significantly enhanced cell sensitivity to ferroptosis-inducing agents. It functions by targeting system Xc- to affect the synthesis of GSH in cells. Therefore, we developed an exosome-based therapeutic approach targeting MKL-1, which provides a novel insight into the treatment of gastric cancer.


Assuntos
Ferroptose , Neoplasias Gástricas , Humanos , Ferroptose/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Apoptose/genética , Glutationa/metabolismo
17.
Cell Cycle ; 22(23-24): 2522-2537, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38193271

RESUMO

LncRNAs are a class of non-coding RNAs that play an important role in regulating gene expression. However, their specific molecular mechanisms in gastric carcinogenesis and metastasis need further exploration. TCGA data showed that the expression of MFGE8, which was closely related to survival, was significantly positively correlated with lncRNA SNHG14. And moreover, the results of high-throughput sequencing and qRT-PCR showed that lncRNA SNHG14 was significantly elevated in gastric cancer. Further, in vitro functional realization showed that lncRNA SNHG14 overexpression significantly increased gastric cancer's proliferation, invasion and migration. Animal experiments also showed that lncRNA SNHG14 overexpression promoted tumorigenesis and metastasis in vivo. Mechanistically, MFGE8 activates the expression of lncRNA SNHG14, which activates the cellular EMT by stabilizing CDH2. Our study suggests that lncRNA SNHG14 could be a potential target for gastric cancer therapy.


Gastric cancer is one of the malignant tumors with a high incidence and high mortality rate worldwide. The current treatment modalities for gastric cancer are surgery, chemotherapy and targeted therapy. However, the 5-year survival rate of gastric cancer patients is still less than 30%. The main reason for the low survival rate of gastric cancer patients is that most cases are already at an advanced disease stage when first diagnosed, with tumor metastasis, tumor heterogeneity and resistance to radiotherapy. TCGA data showed that the expression of MFGE8, which was closely related to survival, was significantly positively correlated with lncRNA SNHG14.We found that lncRNA SNHG14 expression was significantly elevated in gastric cancer by high-throughput sequencing. It was further confirmed in vitro and in vivo that overexpression of lncRNA SNHG14 promoted the proliferation and migration ability of gastric cancer. Mechanistically, lncRNA SNHG14 played an oncogene role by promoting CDH2 expression to activate EMT in tumor cells.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Animais , Neoplasias Gástricas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proliferação de Células/genética , MicroRNAs/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/genética
18.
Aging (Albany NY) ; 15(9): 3394-3409, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-37179120

RESUMO

GRB10 and its family members GRB7 and GRB14 were important adaptor proteins. They regulated many cellular functions by interacting with various tyrosine kinase receptors and other phosphorus-containing amino acid proteins. More and more studies have shown that the abnormal expression of GRB10 is closely related to the occurrence and development of cancer. In our current research, expression data for 33 cancers from the TCGA database was downloaded for analysis. It was found that GRB10 was up-regulated in cholangiocarcinoma, colon adenocarcinoma, head and neck squamous carcinoma, renal chromophobe, clear renal carcinoma, hepatocellular carcinoma, lung adenocarcinoma, lung squamous carcinoma, gastric adenocarcinoma and thyroid carcinoma. Especially in gastric cancer, the high GRB10 expression was closely associated with poorer overall survival. Further research showed that the knockdown of GRB10 inhibited proliferation and migration ability in gastric cancer. Also, there was a potential binding site for miR-379-5p on the 3'UTR of GRB10. Overexpression of miR-379-5p in gastric cancer cells reduced GRB10-regulated gastric cancer proliferation and migration capacity. In addition, we found that tumor growth was slower in a mice xenograft model with knock down of GRB10 expression. These findings suggested that miR-379-5p suppresses gastric cancer development by downregulating GRB10 expression. Therefore, miR-379-5p and GRB10 were expected to be potential targets for the treatment of gastric cancer.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias do Colo , Proteína Adaptadora GRB10 , MicroRNAs , Neoplasias Gástricas , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteína Adaptadora GRB10/genética , Prognóstico , Neoplasias Gástricas/genética
19.
Sci Rep ; 12(1): 21283, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494481

RESUMO

Aldolase A (ALDOA), an important metabolic enzyme in the glycolytic pathway, plays an important role in regulating tumour metabolism. In this study, we investigated the expression pattern of ALDOA in hepatocellular carcinoma (HCC) and its biological role in tumour progression. Bioinformatics analysis, western blot (WB) and RT-qPCR were performed to detect the relative expression of ALDOA in HCC tissues and cell lines. A loss-of-function approach was used to investigate the biological function of ALDOA. The role of ALDOA on glycolysis was assessed by WB, glucose and lactate assay kits and a nude mouse xenograft model. Luciferase reporter experiment, chromatin immunoprecipitation and WB were performed to elucidate the underlying molecular. The expression level of ALODA was up-regulated in HCC tissues and cell lines. High ALDOA levels were associated with poorer patient overall survival. Mechanistic studies suggest that ALDOA is a direct target of miR-34a-5p, which can inhibit glycolysis in hepatocellular carcinoma cells by targeting the 3'UTR of ALDOA. PINK1 antisense RNA (PINK1-AS) competitively sponged miR-34a-5p to increase ALDOA expression by antagonizing miR-34a-5p-mediated ALDOA inhibition. MKL-1 acted as a transcription factor to promote the expression of PINK1-AS and ALDOA, thus promoting the deterioration of HCC cells. This study shows that high expression of ALDOA contributes to the development and poor prognosis of hepatocellular carcinoma and will be a target and potential prognostic biomarker for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Camundongos , Animais , Humanos , Carcinoma Hepatocelular/patologia , Frutose-Bifosfato Aldolase/genética , Frutose-Bifosfato Aldolase/metabolismo , Neoplasias Hepáticas/patologia , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Glicólise/genética , Camundongos Nus
20.
Pathol Res Pract ; 230: 153740, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35007850

RESUMO

Metformin is an oral biguanide used to treat diabetes. Recent study showed it may interfere was related to cancer progression and has a positive effect on cancer prevention and treatment, which attracts a new hot research topic. Here we show that Metformin suppressed the proliferation but induced apoptosis of gastric cells. Notably, Metformin enhanced gastriccell apoptosis via modulating AMPK signaling. Furthermore, Metformin and miR-365 synergistically promote the apoptosis of gastric cancer cells by miR-365-PTEN-AMPK axis. Our study unraveled a novel signaling axis in the regulation in gastric cancer, which could be amplified by the application of metformin. The new effect of metformin potentiates its novel therapeutic application in the future. AVAILABILITY OF DATA AND MATERIALS: The data generated during this study are included in this article and its supplementary information files are available from the corresponding author on reasonable request.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Metformina/farmacologia , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Regiões 3' não Traduzidas , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Fosforilação , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
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