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1.
Int J Med Sci ; 21(6): 1176-1186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774752

RESUMO

Background: To uncover the potential significance of JAK-STAT-SOCS1 axis in penile cancer, our study was the pioneer in exploring the altered expression processes of JAK-STAT-SOCS1 axis in tumorigenesis, malignant progression and lymphatic metastasis of penile cancer. Methods: In current study, the comprehensive analysis of JAK-STAT-SOCS1 axis in penile cancer was analyzed via multiple analysis approaches based on GSE196978 data, single-cell data (6 cancer samples) and bulk RNA data (7 cancer samples and 7 metastasis lymph nodes). Results: Our study observed an altered molecular expression of JAK-STAT-SOCS1 axis during three different stages of penile cancer, from tumorigenesis to malignant progression to lymphatic metastasis. STAT4 was an important dominant molecule in penile cancer, which mediated the immunosuppressive tumor microenvironment by driving the apoptosis of cytotoxic T cell and was also a valuable biomarker of immune checkpoint inhibitor treatment response. Conclusions: Our findings revealed that the complexity of JAK-STAT-SOCS1 axis and the predominant role of STAT4 in penile cancer, which can mediate tumorigenesis, malignant progression, and lymphatic metastasis. This insight provided valuable information for developing precise treatment strategies for patients with penile cancer.


Assuntos
Progressão da Doença , Janus Quinases , Metástase Linfática , Neoplasias Penianas , Fator de Transcrição STAT4 , Proteína 1 Supressora da Sinalização de Citocina , Humanos , Masculino , Neoplasias Penianas/patologia , Neoplasias Penianas/genética , Neoplasias Penianas/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Metástase Linfática/patologia , Metástase Linfática/genética , Janus Quinases/metabolismo , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT4/genética , Regulação Neoplásica da Expressão Gênica , Carcinogênese/genética , Carcinogênese/patologia , Transdução de Sinais , Microambiente Tumoral/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia
2.
J Med Virol ; 95(11): e29208, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37947293

RESUMO

The main proteases (Mpro ) are highly conserved cysteine-rich proteins that can be covalently modified by numerous natural and synthetic compounds. Herein, we constructed an integrative approach to efficiently discover covalent inhibitors of Mpro from complex herbal matrices. This work begins with biological screening of 60 clinically used antiviral herbal medicines, among which Lonicera japonica Flos (LJF) demonstrated the strongest anti-Mpro effect (IC50 = 37.82 µg/mL). Mass spectrometry (MS)-based chemical analysis and chemoproteomic profiling revealed that LJF extract contains at least 50 constituents, of which 22 exhibited the capability to covalently modify Mpro . We subsequently verified the anti-Mpro effects of these covalent binders. Gallic acid and quercetin were found to potently inhibit severe acute respiratory syndrome coronavirus 2 Mpro in dose- and time- dependent manners, with the IC50 values below 10 µM. The inactivation kinetics, binding affinity and binding mode of gallic acid and quercetin were further characterized by fluorescence resonance energy transfer, surface plasmon resonance, and covalent docking simulations. Overall, this study established a practical approach for efficiently discovering the covalent inhibitors of Mpro from herbal medicines by integrating target-based high-throughput screening and MS-based assays, which would greatly facilitate the discovery of key antiviral constituents from medicinal plants.


Assuntos
COVID-19 , Plantas Medicinais , Humanos , SARS-CoV-2 , Ensaios de Triagem em Larga Escala , Quercetina/farmacologia , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Extratos Vegetais/farmacologia , Antivirais/farmacologia , Antivirais/química , Ácido Gálico/farmacologia , Simulação de Acoplamento Molecular
3.
BMC Psychiatry ; 23(1): 651, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667278

RESUMO

BACKGROUND: Evidence shows that negative symptoms of schizophrenia and underlying dysfunctional cognition are related to persistently low functioning and quality of life. However, despite the abundance of existing recovery programs for people with schizophrenia, few have examined whether and how the widely-adopted hope-motivation recovery pathway and the deficit-oriented cognitive pathway might converge to influence functioning and quality of life. METHODS: A cross-sectional, quantative survey recruited a convenient sample of adult outpatients with DSM-5 schizophrenia spectrum disorders and low social functioning (n = 124). Self-reported measurements included personal recovery (30-item Mental Health Recovery Measure), social functioning (8-item Social Functioning Questionnaire), hope (12-item Hope Scale), quality of life (28-item World Health Organization Quality of Life Scale-Abbreviated Version-Hong Kong), defeatist beliefs (15-item extracted from Dysfunctional Attitude Scale), and asocial beliefs (15-item extracted from Revised Social Anhedonia Scale). Correlation analysis and structural equation modelling was applied to investigate how the two pathways intertwined to predict social functioning and quality of life. RESULTS: Asocial beliefs and hope separately mediated two partial mediation pathways from defeatist beliefs to recovery outcomes (social functioning and personal recovery). Meanwhile, defeatist beliefs, social functioning, and personal recovery further predicted quality of life. CONCLUSIONS: This is one of the very few studies that provides empirical evidence of a deficit-strength linkage in the recovery from schizophrenia. Remediation of dysfunctional beliefs and the injection of hope and successful experiences should be undertaken concurrently in recovery as they are associated with differential effects on enhancing social functioning and personal recovery, which then converge and contribute to a better quality of life.


Assuntos
Esquizofrenia , Adulto , Humanos , Esquizofrenia/terapia , Estudos Transversais , Qualidade de Vida , Anedonia , Cognição
4.
Arch Biochem Biophys ; 727: 109306, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35667444

RESUMO

Structurally abnormal Cu, Zn-superoxide dismutase (SOD1) is considered one of the causes of amyotrophic lateral sclerosis. The misfolding and neurotoxic aggregation of SOD1 can be induced by mutations, metal deficiency, and post-translational modification. Here, we revealed the risk of oxidation damage on zinc-deficient SOD1 by native mass spectrometry coupled with ion mobility. The copper ions were found to be released in the early period of oxidation which may be the result of oxidation on its binding site. On the other hand, zinc-deficient SOD1 showed a faster and deeper dissociation tendency than SOD1 with no metal ions. The results of collision-induced unfolding indicated that the oxidized zinc-deficient SOD1 is more easily to be turned into totally unfolded conformation. ThT fluorescence also showed stronger aggregation of oxidized zinc-deficient SOD1. Compared with DTT-induced reduction, oxidized zinc-deficient SOD1 acted differently in dimer dissociation, conformation stability, and aggregation, suggesting that the conserved intramolecular disulfide bonds were influenced little during oxidation. Additionally, we explored glycitin, an isoflavone glycoside, to prevent the oxidation of metal-deficient SOD1 and inhibit the unfolding and aggregation of oxidized metal-deficient SOD1.


Assuntos
Esclerose Lateral Amiotrófica , Isoflavonas , Desdobramento de Proteína , Cobre/química , Humanos , Isoflavonas/farmacologia , Espectrometria de Massas , Metais , Mutação , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/metabolismo , Zinco/química
5.
Rapid Commun Mass Spectrom ; 36(6): e9251, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34978114

RESUMO

RATIONALE: A large number of studies have shown that the production of aberrant and deleterious copper zinc superoxide dismutase (SOD1) species is closely related to amyotrophic lateral sclerosis (ALS). Therefore, it is of great significance to screen effective inhibitors of misfolding and aggregation of SOD1 for treating ALS disease. METHODS: The interaction between flavanone compounds with apo-SOD1was investigated using native electrospray ion mobility mass spectrometry (native ESI-IM-MS). Binding affinities of ligands were compared using native MS, ESI-MS/MS, collision-induced unfolding, and competitive experiments. The effect of ligands on apo-SOD1 aggregation was investigated using the fluorescence spectroscopy method. RESULTS: The results of MS showed that the binding affinity of liquiritin apioside was the strongest, better than the corresponding monosaccharide and aglycone, indicating that the presence and the number of glycosyl group are beneficial to enhance ligand affinity to protein. The results of fluorescence spectroscopy for inhibiting protein aggregation in vitro were consistent with the binding affinity. In addition, the results of the collision-induced unfolding indicated that liquiritin apioside can slow down the unfolding of the protein. Meanwhile, the results of competition experiment suggested that liquiritin apiosides share different binding sites with naringin and 5-fluorouridine, which are significant for the structural stability of SOD1. CONCLUSIONS: This study revealed that the binding of liquiritin apioside can stabilize apo-SOD1 dimer and inhibit the aggregation of apo-SOD1, and illustrated that native ESI-IM-MS is a powerful tool for providing insight into investigating the structure-activity relationship between small molecules and protein, and screening protein conformation stabilizers.


Assuntos
Flavanonas/química , Espectrometria de Mobilidade Iônica/métodos , Precursores de Proteínas/química , Espectrometria de Fluorescência/métodos , Superóxido Dismutase-1/química , Sítios de Ligação , Dimerização , Humanos , Cinética , Agregados Proteicos , Conformação Proteica , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Estabilidade Proteica , Superóxido Dismutase-1/metabolismo
6.
World J Surg Oncol ; 20(1): 368, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36419094

RESUMO

BACKGROUND: This study aimed to investigate FAM84B expression in glioma tissues and explore the role of FAM84B in promoting the proliferation of glioma cells and the mechanism of regulating the cell cycle pathways. METHODS: The TCGA database was adopted to analyze FAM84B expression in glioma tissues. The FAM84B expression was detected by qRT-PCR in patients with glioma, especially that in glioma cells, U251, LN-229, U98, and U87. Two glioma cell lines U87 and T98 were selected for siRNA transfection, which were divided into si-NC si-FAM84B-1 and si-FAM84B-2 groups. The effect of FAM84B on the proliferation of glioma cells was detected with the MTT experiment and that on the glioma cell cycle was detected with the flow cytometry. The signaling pathways potentially regulated by FAM84B in glioma were analyzed through the bioinformatics analysis. The expression of proteins, Cyclin D1, CDK4, Cdk6, and p21, in the cell cycle-related pathways in cells of each group was detected by the Western blot. RESULTS: TCGA database results showed a significantly higher FAM84B expression in glioma tissues than that in paracancerous tissues. According to the detection of qRT-PCR, FAM84B expressed the highest in the glioma cell line U87 (P < 0.05). Compared with the serum of healthy controls, FAM84B mRNA expression significantly increased in patients with gliomas. And compared with the si-NC group, the proliferation ability of U87 and T98 cells decreased and the cell cycle was blocked in the G0/G1 phase in both si-FAM84B transfection groups (P < 0.05). According to the bioinformatics analysis, FAM84B regulated the cell cycle pathways in glioma. FAM84B siRNA inhibited the expression of key proteins, Cyclin D1, CDK2, CDK4, and Cdk6, of the cell cycle pathways in glioma cells and promoted the expression of P53 and P21 proteins. CONCLUSIONS: In conclusion, FAM84B may inhibit the proliferation of glioma cells by regulating the cell cycle pathways.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Ciclina D1/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , RNA Interferente Pequeno , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Ciclo Celular/genética
7.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430215

RESUMO

Metastasis is one of the main obstacles for the treatment and prognosis of breast cancer. In this study, the effects and possible mechanisms of aloe emodin (AE) and emodin (EMD) for inhibiting breast cancer metastasis were investigated via cell metabolomics. First, a co-culture model of MCF-7 and HUVEC cells was established and compared with a traditional single culture of MCF-7 cells. The results showed that HUVEC cells could promote the development of cancer cells to a malignant phenotype. Moreover, AE and EMD could inhibit adhesion, invasion, and angiogenesis and induce anoikis of MCF-7 cells in co-culture model. Then, the potential mechanisms behind AE and EMD inhibition of MCF-7 cell metastasis were explored using a metabolomics method based on UPLC-Q-TOF/MS multivariate statistical analysis. Consequently, 27 and 13 biomarkers were identified in AE and EMD groups, respectively, including polyamine metabolism, methionine cycle, TCA cycle, glutathione metabolism, purine metabolism, and aspartate synthesis. The typical metabolites were quantitatively analyzed, and the results showed that the inhibitory effect of AE was significantly better than EMD. All results confirmed that AE and EMD could inhibit metastasis of breast cancer cells through different pathways. Our study provides an overall view of the underlying mechanisms of AE and EMD against breast cancer metastasis.


Assuntos
Emodina , Segunda Neoplasia Primária , Humanos , Emodina/farmacologia , Antraquinonas/farmacologia , Metabolômica , Melanoma Maligno Cutâneo
8.
Molecules ; 27(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36364128

RESUMO

The deficiency or wrong combination of metal ions in Cu, Zn-superoxide dismutase (SOD1), is regarded as one of the main factors causing the aggregation of SOD1 and then inducing amyotrophic lateral sclerosis (ALS). A ligands-targets screening process based on native electrospray ionization ion mobility mass spectrometry (ESI-IMS-MS) was established in this study. Four glycosides including daidzin, sophoricoside, glycitin, and genistin were screened out from seven soybean isoflavone compounds and were found to interact with zinc-deficient or metal-free SOD1. The structure and conformation stability of metal-free and zinc-deficient SOD1 and their complexes with the four glycosides was investigated by collision-induced dissociation (CID) and collision-induced unfolding (CIU). The four glycosides could strongly bind to the metal-free and copper recombined SOD1 and enhance the folding stability of these proteins. Additionally, the ThT fluorescence assay showed that these glycosides could inhibit the toxic aggregation of the zinc-deficient or metal-free SOD1. The competitive interaction experiments together with molecular docking indicate that glycitin, which showed the best stabilizing effects, binds with SOD1 between ß-sheet 6 and loop IV. In short, this study provides good insight into the relationship between inhibitors and different SOD1s.


Assuntos
Esclerose Lateral Amiotrófica , Isoflavonas , Zinco/química , Superóxido Dismutase-1/metabolismo , Glycine max/metabolismo , Simulação de Acoplamento Molecular , Superóxido Dismutase/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Cobre/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Isoflavonas/farmacologia , Glicosídeos , Mutação
9.
Molecules ; 27(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209071

RESUMO

The cause of death in most breast cancer patients is disease metastasis and the occurrence of multidrug resistance (MDR). Ornithine decarboxylase (ODC), which is involved into multiple pathways, is closely related to carcinogenesis and development. Ursolic acid (UA), a natural triterpenoid compound, has been shown to reverse the MDR characteristics of tumor cells. However, the effect of UA on the invasion and metastasis of tumor cells with MDR is not known. Therefore, we investigated the effects of UA on invasion and metastasis, ODC-related polyamine metabolism, and MAPK-Erk-VEGF/MMP-9 signaling pathways in a doxorubicin-resistant breast cancer cell (MCF-7/ADR) model. The obtained results showed that UA significantly inhibited the adhesion and migration of MCF-7/ADR cells, and had higher affinities with key active cavity residues of ODC compared to the known inhibitor di-fluoro-methyl-ornithine (DFMO). UA could downregulate ODC, phosphorylated Erk (P-Erk), VEGF, and matrix metalloproteinase-9 (MMP-9) activity. Meanwhile, UA significantly reduced the content of metabolites of the polyamine metabolism. Furthermore, UA increased the intracellular accumulation of Dox in MCF-7/ADR cells. Taken together, UA can inhibit against tumor progression during the treatment of breast cancer with Dox, and possibly modulate the Erk-VEGF/MMP-9 signaling pathways and polyamine metabolism by targeting ODC to exert these effects.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Movimento Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Proteínas de Transporte/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Células Endoteliais/metabolismo , Feminino , Humanos , Células MCF-7 , Modelos Moleculares , Estrutura Molecular , Ornitina Descarboxilase/química , Ornitina Descarboxilase/metabolismo , Fosforilação , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Triterpenos/química , Ácido Ursólico
10.
Child Fam Soc Work ; 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35941859

RESUMO

This study tested an ecological model of resilience that illustrated the influence of COVID-19-related stressors (i.e., social and health stressors) and various socio-ecological factors at microsystem (i.e., parent-child conflicts and couple relationship) and exo-system levels (i.e., the utilization of community resources) on family functioning among Chinese families during COVID-19. An anonymous telephone survey was conducted using random sampling method. The sample contained 322 respondents who were co-habiting with their child(ren) and their partner. Hierarchical regression analysis and structural equation modelling were used to examine the differential impacts of various levels of factors and the model that were proposed. Results showed that 13.2% of the households were categorized as at-risk of poorer family functioning. Couple relationship and stressors significantly accounted for much of the variance in family functioning. While stressors had a significant direct effect on family functioning, couple relationship, but not parent-child conflicts or utilization of community resources, significantly mediated and moderated the impact of stressors on family functioning. The findings highlighted the impacts of both individual and ecological factors on family functioning under COVID-19. Importantly, cultural and contextual factors should be considered when adopting ecological model of resilience to examine family functioning in diverse cultural groups.

11.
J Transl Med ; 19(1): 152, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33858428

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a common metabolic disease that affects 20-30% of individuals worldwide. Liver puncture remains the gold standard for the diagnosis of liver diseases despite limitations regarding invasive nature and sample variability. It is of great clinical significance to find noninvasive biomarkers to detect and predict NAFLD. OBJECTIVE: The aims of this study were to identify potential serum markers in individuals with early-stage NAFLD and to advance the mechanistic understanding of this disease using a high-throughput mass spectrometry-based untargeted metabolomics approach. METHODS: One hundred and twelve patients with early-stage NAFLD aged 18-55 were recruited according to the guidelines. The control group included 112 healthy participants. The demographic, anthropometric, clinical and laboratory data of all participants were systematically collected. Serum samples were obtained after an overnight fast. The comprehensive serum metabolomic analysis was performed by ultra-performance liquid chromatography-Orbitrap mass spectrometry. The resultant data was processed by Compound Discover and SIMCA-P software to validate the potential biomarkers. Significantly altered metabolites were evaluated by variable importance in projection value (VIP > 1) and ANOVA (p < 0.01). Pathway analysis was performed using MetaboAnalyst 4.0. RESULTS: The liver function test of early NAFLD patients showed no statistical differences to control group (p > 0.05). However, obvious differences in blood lipids were observed between subjects with NAFLD and controls (p < 0.001). In total, 55 metabolites showed significant changes in experimental group were identified. The area under curve (AUC) values deduced by receiver operating curve (ROC) analysis indicated that these newly identified biomarkers have high predictability and reliability. Of these, 15 metabolites with AUC greater than 0.9 were of great diagnostic value in early NAFLD patients. CONCLUSION: In this study, a total of 15 serum metabolites were found to strongly associate with early NAFLD. These biomarkers may have great clinical significance in the early diagnosis of NAFLD, as well as to follow response to therapeutic interventions.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adolescente , Adulto , Biomarcadores , Cromatografia Líquida , Humanos , Espectrometria de Massas , Metabolômica , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Reprodutibilidade dos Testes , Adulto Jovem
12.
Soc Psychiatry Psychiatr Epidemiol ; 56(12): 2311-2322, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34100978

RESUMO

PURPOSE: Hong Kong has experienced four waves of COVID-19 since the first case was confirmed in January 2020. Several studies have highlighted the psychological impacts of the outbreak in Hong Kong but have largely ignored the protective factors that contribute to resilience among vulnerable families. This study adopted an ecological resilience framework to explore the impact of this epidemic on members of families with youth with a delinquent tendency/mental health concerns and the ecological protective factors for these vulnerable families. METHODS: Random sampling based on a sampling frame provided by one of the largest local social service organizations in Hong Kong led to the recruitment of 407 respondents who were interviewed using a battery of standardized questionnaires. RESULTS: The results showed that 30.6% and 11.5% of respondents reported a moderate and a severe level of psychological distress, respectively, almost double the percentages reported in a previous study conducted in Hong Kong before the COVID-19 outbreak. Around 36.6% of respondents indicated they had encountered financial problems and almost 40% indicated aggravated financial circumstances since the outbreak. Hierarchical regression analysis revealed that financial stress was the strongest predictor of psychological distress. Structural equation modeling indicated that family support, indoor leisure activities and community resources significantly mediated the negative influence of COVID-19-related stressors on psychological distress of family members. CONCLUSION: Family leisure activities, family support, community spirit and mutual help within the context of social-distancing restrictions may need to be promoted to benefit vulnerable families in Hong Kong under the COVID-19 epidemic.


Assuntos
COVID-19 , Adolescente , Surtos de Doenças , Hong Kong/epidemiologia , Humanos , Saúde Mental , SARS-CoV-2
13.
Phytother Res ; 35(7): 3886-3897, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33792091

RESUMO

Multidrug resistance (MDR) is one of the major obstacles for clinical effective chemotherapy. In this study, the effects and possible mechanisms of aloe-emodin (AE) were investigated on reversing the adriamycin (ADR)-induced resistance of MCF-7/ADR cells. AE could significantly reverse the ADR resistance in MCF-7/ADR cells. The combination of AE (20 µM) and ADR had no effect on the P-glycoprotein (P-gp) level, but notably promoted the accumulation of ADR in drug-resistant cells. The efflux function of P-gp required ATP, but AE reduced the intracellular ATP level. AE played a reversal role might through inhibiting the efflux function of P-gp. The research result of energy metabolism pathways indicated that combination of AE and ADR could inhibit glycolysis, tricarboxylic acid (TCA) cycle, glutamine metabolism, and related amino acid synthesis pathways. Moreover, we found AE not only reversed ADR-induced resistant but also induced autophagy as a defense mechanism. In addition, the combination of AE and ADR arrested G2/M cell cycle and induced apoptosis through DNA damage, ROS generation, caspase-3 activation. Our study indicated that AE could be a potential reversal agent to resensitize ADR resistant in tumor chemotherapy and inhibiting autophagy might be an effective strategy to further enhance the reversal activity of AE.


Assuntos
Aloe , Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Emodina , Aloe/química , Doxorrubicina/farmacologia , Emodina/farmacologia , Feminino , Humanos , Células MCF-7
16.
Anal Chem ; 88(23): 11720-11726, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27760293

RESUMO

Misfolding and aggregation of Cu, Zn superoxide dismutase (SOD1) is implicated in the etiology of amyotrophic lateral sclerosis (ALS). The use of small molecules may stabilize the spatial structure of SOD1 dimer, thus, preventing its dissociation and aggregation. In this study, "native" mass spectrometry (MS) was used to study the noncovalent interactions between SOD1 and flavonoid compounds. MS experiments were performed on a quadruple time-of-flight (Q-ToF) mass spectrometer with an electrospray ionization (ESI) source and T-wave ion mobility. ESI-MS was used to detect the SOD1-flavonoid complexes and compare their relative binding strengths. The complement of ion mobility separation allowed comparison in the binding affinities between flavonoid isomers and provided information on the conformational changes. Molecular docking together with molecular dynamics simulations and MM/PBSA methods were applied to gain insights into the binding modes and free energies of SOD1-flavonoid complexes at the molecule level. Among all the flavonoids investigated, flavonoid glycosides preferentially bind to SOD1 than their aglycone counterparts. Naringin, one of the compounds that has the strongest binding affinity to SOD1, was subjected to further characterization. Experiment results show that the binding of naringin can stabilize SOD1 dimer and inhibit the aggregation of SOD1. Molecular simulation results suggest that naringin could reduce the dissociation of SOD1 dimers through direct interaction with the dimer interface. This developed analytical strategy could also be applied to study the interactions between SOD1 and other drug-like molecules, which may have the effect to reduce the aggregation.


Assuntos
Flavonoides/química , Simulação de Acoplamento Molecular , Superóxido Dismutase-1/química , Animais , Bovinos , Eritrócitos/enzimologia , Flavonoides/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Superóxido Dismutase-1/metabolismo , Termodinâmica
17.
Anal Bioanal Chem ; 408(21): 5843-5854, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27379392

RESUMO

Although anticancer drug resistance has been linked to high expression of P-glycoprotein and the enhanced DNA repair ability, the biochemical process and the underlying mechanisms of drug resistance are not clear. In order to clarify the biochemical mechanisms of drug resistance during anticancer drug treatment, we studied the metabolomics of MCF-7/S and MCF-7/Adr cell lines, the COC1 and COC1/DDP cell lines, including the metabolic pathways of multidrug-resistant tumor cells and the changes of endogenous substances in cells. The intracellular metabolites were profiled using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In this study, 24 biomarkers in MCF-7/Adr cells and 15 biomarkers in COC1/DDP cells that are involved in some important metabolic pathways were putatively identified. Several metabolic pathways are changed in tumor cells showing drug resistance, such as protein synthesis pathways, cysteine synthesis, the glutamine metabolic pathway, and the ammonia cycle; the first of these are involved in the synthesis of some important proteins including membrane proteins, multidrug resistance-associated proteins, and P-glycoprotein (P-gp). Proteins related to drug resistance were overexpressed in multidrug-resistant tumor cells. These proteins depended on energy and play important roles in the emergence of drug resistance. The changes in glutathione and cysteine metabolic pathways showed that the cells can activate related metabolic pathways and reduce the cell apoptosis when they encounter oxidative damage. These findings indicate that drug resistance is likely associated with increased P-gp synthesis and reduced apoptosis of tumor cells. Graphical Abstract Drug resistance was charactered in the changing of genomics and proteomics. Like enhancing DNA repair, reducing uptake, high P-g protein expression. Here, we studied the changes of metabolite pathway which could be also play an imported role in drug resistance.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Redes e Vias Metabólicas/efeitos dos fármacos , Metabolômica/métodos , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Resistência a Múltiplos Medicamentos , Feminino , Humanos , Células MCF-7 , Espectrometria de Massas em Tandem/métodos
19.
Biomed Chromatogr ; 29(7): 1027-34, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25425064

RESUMO

Bulleyaconitine A (BLA) from Aconitum bulleyanum plants is usually used as anti-inflammatory drug in some Asian countries. It has a variety of bioactivities, and at the same time some toxicities. Since the bioactivities and toxicities of BLA are closely related to its metabolism, the metabolites and the metabolic pathways of BLA in rat liver microsomes were investigated by HPLC-MS(n). In this research, the 12 metabolites of BLA were identified according to the results of HPLC-MS(n) data and the relevant literature. The results showed that there are multiple metabolites of BLA in rat liver microsomes, including demethylation, deacetylation, dehydrogenation deacetylation and hydroxylation. The major metabolic pathways of BLA in rat liver microsomes were clarified by HPLC-MS combined with specific inhibitors of CYP450 isoforms. As a result, CYP3A and 2C were found to be the principal CYP isoforms contributing to the metabolism of BLA. Moreover, CYP2D6 and 2E1 are also more important CYP isoforms for the metabolism of BLA. While CYP1A2 only affected the formation rate of M11, its effect on the metabolism of BLA is very small.


Assuntos
Aconitina/análogos & derivados , Cromatografia Líquida/métodos , Microssomos Hepáticos/metabolismo , Espectrometria de Massas em Tandem/métodos , Aconitina/análise , Aconitina/química , Aconitina/metabolismo , Animais , Sistema Enzimático do Citocromo P-450 , Masculino , Redes e Vias Metabólicas , Ratos , Ratos Sprague-Dawley
20.
Anal Chem ; 86(23): 11599-605, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25361402

RESUMO

Cu, Zn-superoxide dismutase (SOD1) is a homodimeric enzyme of approximately 32 kDa. Each monomer contains one Cu(2+) and one Zn(2+) ion, which play catalytic and structural roles in the enzyme. Dimer formation is also essential to its functionality. The spatial structure of this metalloenzyme is also closely related to its bioactivities. Here we investigate the structural and conformational changes of SOD1 in the gas phase by electrospray ionization mass spectrometry (ESI-MS) and ion-mobility (IM) separation combined with tandem mass spectrometry (MS/MS). First, the composition and forms of SOD1 were analyzed by ESI-MS. The dimer, monomer, and apomonomer were observed under different solvent conditions. The dimer was found to be stable, and could retain its native structure in neutral buffer. Ion-mobility separation combined with MS/MS was used to reveal the conformational changes and dissociation process of SOD1 when it was activated in the gas phase. Three different dimeric and two monomeric conformers were observed; three unfolding and dissociation pathways were also identified. The results from this study demonstrate that IM-MS/MS could be used to obtain spatial structural information on SOD1 and that the technique could therefore be employed to investigate the conformational changes in mutant SOD1, which is related to amyotrophic lateral sclerosis and other neurodegenerative disorders.


Assuntos
Desdobramento de Proteína , Superóxido Dismutase/química , Animais , Bovinos , Gases/química , Gases/metabolismo , Espectrometria de Massas , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1
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