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1.
Cancers (Basel) ; 16(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39001490

RESUMO

Chemotherapy remains a cornerstone in lung cancer treatment, yet emerging evidence suggests that sublethal low doses may inadvertently enhance the malignancy. This study investigates the paradoxical effects of sublethal low-dose chemotherapy on non-small-cell lung cancer (NSCLC) cells, emphasizing the role of Aldo-keto reductase family 1 member B10 (AKR1B10). We found that sublethal doses of chemotherapy unexpectedly increased cancer cell migration approximately 2-fold and invasion approximately threefold, potentially promoting metastasis. Our analysis revealed a significant upregulation of AKR1B10 in response to taxol and doxorubicin treatment, correlating with poor survival rates in lung cancer patients. Furthermore, silencing AKR1B10 resulted in a 1-2-fold reduction in cell proliferation and a 2-3-fold reduction in colony formation and migration while increasing chemotherapy sensitivity. In contrast, the overexpression of AKR1B10 stimulated growth rate by approximately 2-fold via ERK pathway activation, underscoring its potential as a target for therapeutic intervention. The reversal of these effects upon the application of an ERK-specific inhibitor further validates the significance of the ERK pathway in AKR1B10-mediated chemoresistance. In conclusion, our findings significantly contribute to the understanding of chemotherapy-induced adaptations in lung cancer cells. The elevated AKR1B10 expression following sublethal chemotherapy presents a novel molecular mechanism contributing to the development of chemoresistance. It highlights the need for strategic approaches in chemotherapy administration to circumvent the inadvertent enhancement of cancer aggressiveness. This study positions AKR1B10 as a potential therapeutic target, offering a new avenue to improve lung cancer treatment outcomes by mitigating the adverse effects of sublethal chemotherapy.

2.
Nutrients ; 15(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37960146

RESUMO

Prostate cancer (PC) is the second most frequently diagnosed cancer and the fifth leading cause of cancer-related death in males worldwide. Early-stage PC patients can benefit from surgical, radiation, and hormonal therapies; however, once the tumor transitions to an androgen-refractory state, the efficacy of treatments diminishes considerably. Recently, the exploration of natural products, particularly dietary phytochemicals, has intensified in response to addressing this prevailing medical challenge. In this study, we uncovered a synergistic effect from combinatorial treatment with lovastatin (an active component in red yeast rice) and Antrodia camphorata (AC, a folk mushroom) extract against PC3 human androgen-refractory PC cells. This combinatorial modality resulted in cell cycle arrest at the G0/G1 phase and induced apoptosis, accompanied by a marked reduction in molecules responsible for cellular proliferation (p-Rb/Rb, Cyclin A, Cyclin D1, and CDK1), aggressiveness (AXL, p-AKT, and survivin), and stemness (SIRT1, Notch1, and c-Myc). In contrast, treatment with either AC or lovastatin alone only exerted limited impacts on the cell cycle, apoptosis, and the aforementioned signaling molecules. Notably, significant reductions in canonical PC stemness markers (CD44 and CD133) were observed in lovastatin/AC-treated PC3 cells. Furthermore, lovastatin and AC have been individually examined for their anti-PC properties. Our findings elucidate a pioneering discovery in the synergistic combinatorial efficacy of AC and clinically viable concentrations of lovastatin on PC3 PC cells, offering novel insights into improving the therapeutic effects of dietary natural products for future strategic design of therapeutics against androgen-refractory prostate cancer.


Assuntos
Produtos Biológicos , Neoplasias da Próstata , Masculino , Humanos , Androgênios/metabolismo , Células PC-3 , Lovastatina/farmacologia , Proliferação de Células , Apoptose , Neoplasias da Próstata/patologia , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Linhagem Celular Tumoral
3.
Int J Mol Sci ; 24(19)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37834326

RESUMO

About 80% of lung cancer patients are diagnosed with non-small cell lung cancer (NSCLC). EGFR mutation and overexpression are common in NSCLC, thus making EGFR signaling a key target for therapy. While EGFR kinase inhibitors (EGFR-TKIs) are widely used and efficacious in treatment, increases in resistance and tumor recurrence with alternative survival pathway activation, such as that of AXL and MET, occur frequently. AXL is one of the EMT (epithelial-mesenchymal transition) signature genes, and EMT morphological changes are also responsible for EGFR-TKI resistance. MIG6 is a negative regulator of ERBB signaling and has been reported to be positively correlated with EGFR-TKI resistance, and downregulation of MIG6 by miR-200 enhances EMT transition. While MIG6 and AXL are both correlated with EMT and EGFR signaling pathways, how AXL, MIG6 and EGFR interplay in lung cancer remains elusive. Correlations between AXL and MIG6 expression were analyzed using Oncomine or the CCLE. A luciferase reporter assay was used for determining MIG6 promoter activity. Ectopic overexpression, RNA interference, Western blot analysis, qRT-PCR, a proximity ligation assay and a coimmunoprecipitation assay were performed to analyze the effects of certain gene expressions on protein-protein interaction and to explore the underlying mechanisms. An in vitro kinase assay and LC-MS/MS were utilized to determine the phosphorylation sites of AXL. In this study, we demonstrate that MIG6 is a novel substrate of AXL and is stabilized upon phosphorylation at Y310 and Y394/395 by AXL. This study reveals a connection between MIG6 and AXL in lung cancer. AXL phosphorylates and stabilizes MIG6 protein, and in this way EGFR signaling may be modulated. This study may provide new insights into the EGFR regulatory network and may help to advance cancer treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Fosforilação , Neoplasias Pulmonares/metabolismo , Receptores ErbB/metabolismo , Cromatografia Líquida , Inibidores de Proteínas Quinases/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Espectrometria de Massas em Tandem , Recidiva Local de Neoplasia , Mutação
4.
Biochem Biophys Res Commun ; 682: 365-370, 2023 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-37839105

RESUMO

In non-small cell lung cancer (NSCLC), the receptor tyrosine kinase AXL has been identified as a potent activator of tumor progression and resistance to therapies. However, the molecular mechanisms behind AXL-mediated oncogenesis remain elusive. Current study thus aimed to uncover potential downstream genes regulated by AXL in NSCLC. Through transcriptomic RNA sequencing of AXL-silenced NSCLC cells, TMEM14A was identified as a significantly up-regulated gene. Clinical evaluations using GEPIA2 revealed that TMEM14A mRNA expression was notably higher in lung adenocarcinoma (LUAD) tumor tissues compared to normal tissues. Further, significantly increased TMEM14A levels were associated with poorer overall survival in LUAD patients. Experimentally, silencing TMEM14A in NSCLC cells led to reduced cellular proliferation and ATP levels, highlighting a key role of TMEM14A in NSCLC progression. Moreover, our promoter analysis demonstrated that AXL-mediated regulation of TMEM14A transcription could involve binding of transcription factors STAT and NF-κB to 5'-promoter of TMEM14A. Collectively, current study unveils TMEM14A as a novel downstream target of AXL, suggesting its potential as a therapeutic target to counteract resistance in future NSCLC patients undergoing AXL-targeted therapies.


Assuntos
Receptor Tirosina Quinase Axl , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Receptor Tirosina Quinase Axl/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Pulmonares/patologia , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-36767919

RESUMO

BACKGROUND: Metabolic syndrome is characterized by cardiovascular and chronic disease risk factors that cause health problems. Inequalities in medical resources and information present a challenge in this context. Indigenous communities may be unaware of their risk for metabolic syndrome. AIMS: This study explored factors associated with metabolic syndrome-related knowledge, attitudes, and behaviors among Taiwanese indigenous communities. METHODS: For this descriptive cross-sectional survey, we collected anthropometric data and used a self-administered questionnaire between 1 July 2016, to 31 July 2017, from a convenience sample of an indigenous tribe in eastern Taiwan. The response rate was 92%. RESULTS: The prevalence of metabolic syndrome was as high as 71%, and the average correct knowledge rate was 39.1%. The participants' self-management attitudes were mainly negative, and the self-management behaviors were low in this population. Stepwise regression analysis showed that knowledge, attitude, age, perception of physical condition, and body mass index, which accounted for 65% of the total variance, were the most predictive variables for self-management behaviors. CONCLUSIONS: This is the first study to report the relationship between metabolic syndrome knowledge, attitudes, and behaviors in an indigenous population. There is an urgent need to develop safety-based MetS health education programs that can provide access to the right information and enhance self-management approaches to lessen the growing burden of MetS in indigenous communities.


Assuntos
Síndrome Metabólica , Humanos , Síndrome Metabólica/epidemiologia , Estudos Transversais , Taiwan/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Índice de Massa Corporal
7.
J Biomed Sci ; 29(1): 109, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550569

RESUMO

BACKGROUND: Ovarian cancer has the highest mortality among gynecological cancers due to late diagnosis and lack of effective targeted therapy. Although the study of interplay between cancer cells with their microenvironment is emerging, how ovarian cancer triggers signaling that coordinates with immune cells to promote metastasis is still elusive. METHODS: Microarray and bioinformatics analysis of low and highly invasive ovarian cancer cell lines were used to reveal periostin (POSTN), a matrix protein with multifunctions in cancer, with elevated expression in the highly invasive cells. Anchorage independent assay, Western blot, RNA interference, confocal analysis and neutralizing antibody treatment were performed to analyze the effects of POSTN on tumor promotion and to explore the underlying mechanism. Chemotaxis, flow cytometry and cytokine array analyses were undertaken to analyze the involvement of POSTN in cancer-associated fibroblast (CAF) and macrophage modulation. Correlations between POSTN expression levels and clinical characteristics were analyzed using the Oncomine, commercial ovarian cancer cDNA and China Medical University Hospital patient cohort. In vivo effect of POSTN on metastasis was studied using a mouse xenograft model. RESULTS: Expression of POSTN was found to be elevated in highly invasive ovarian cancer cells. We observed that POSTN was co-localized with integrin ß3 and integrin ß5, which was important for POSTN-mediated activation of ERK and NF-κB. Ectopic expression of POSTN enhanced whereas knockdown of POSTN decreased cancer cell migration and invasion in vitro, as well as tumor growth and metastasis in vivo. POSTN enhanced integrin/ERK/NF-κB signaling through an autocrine effect on cancer cells to produce macrophage attracting and mobilizing cytokines including MIP-1ß, MCP-1, TNFα and RANTES resulting in increased chemotaxis of THP-1 monocytes and their polarization to M2 macrophages in vitro. In agreement, tumors derived from POSTN-overexpressing SKOV3 harbored more tumor-associated macrophages than the control tumors. POSTN induced TGF-ß2 expression from ovarian cancer cells to promote activation of adipose-derived stromal cells to become CAF-like cells expressing alpha smooth muscle actin and fibroblast activation protein alpha. Consistently, increased CAFs were observed in POSTN overexpressing SKOV3 cells-derived metastatic tumors. In clinical relevance, we found that expression of POSTN was positively correlated with advanced-stage diseases and poor overall survival of patients. CONCLUSIONS: Our study revealed a POSTN-integrin-NF-κB-mediated signaling and its involvement in enhancing M2 macrophages and CAFs, which could potentially participate in promoting tumor growth. Our results suggest that POSTN could be a useful prognosis marker and potential therapeutic target.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Ovarianas , Feminino , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Integrinas/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Linhagem Celular Tumoral , Neoplasias Ovarianas/genética , Citocinas/metabolismo , Macrófagos/metabolismo , Microambiente Tumoral/genética
8.
J Biomed Sci ; 29(1): 42, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35706019

RESUMO

BACKGROUND: The development of drug resistance in oral squamous cell carcinoma (OSCC) that frequently leads to recurrence and metastasis after initial treatment remains an unresolved challenge. Presence of cancer stem cells (CSCs) has been increasingly reported to be a critical contributing factor in drug resistance, tumor recurrence and metastasis. Thus, unveiling of mechanisms regulating CSCs and potential targets for developing their inhibitors will be instrumental for improving OSCC therapy. METHODS: siRNA, shRNA and miRNA that specifically target keratin 17 (KRT17) were used for modulation of gene expression and functional analyses. Sphere-formation and invasion/migration assays were utilized to assess cancer cell stemness and epithelial mesenchymal transition (EMT) properties, respectively. Duolink proximity ligation assay (PLA) was used to examine molecular proximity between KRT17 and plectin, which is a large protein that binds cytoskeleton components. Cell proliferation assay was employed to evaluate growth rates and viability of oral cancer cells treated with cisplatin, carboplatin or dasatinib. Xenograft mouse tumor model was used to evaluate the effect of KRT17- knockdown in OSCC cells on tumor growth and drug sensitization. RESULTS: Significantly elevated expression of KRT17 in highly invasive OSCC cell lines and advanced tumor specimens were observed and high KRT17 expression was correlated with poor overall survival. KRT17 gene silencing in OSCC cells attenuated their stemness properties including markedly reduced sphere forming ability and expression of stemness and EMT markers. We identified a novel signaling cascade orchestrated by KRT17 where its association with plectin resulted in activation of integrin ß4/α6, increased phosphorylation of FAK, Src and ERK, as well as stabilization and nuclear translocation of ß-catenin. The activation of this signaling cascade was correlated with enhanced OSCC cancer stemness and elevated expression of CD44 and epidermal growth factor receptor (EGFR). We identified and demonstrated KRT17 to be a direct target of miRNA-485-5p. Ectopic expression of miRNA-485-5p inhibited OSCC sphere formation and caused sensitization of cancer cells towards cisplatin and carboplatin, which could be significantly rescued by KRT17 overexpression. Dasatinib treatment that inhibited KRT17-mediated Src activation also resulted in OSCC drug sensitization. In OSCC xenograft mouse model, KRT17 knockdown significantly inhibited tumor growth, and combinatorial treatment with cisplatin elicited a greater tumor inhibitory effect. Consistently, markedly reduced levels of integrin ß4, active ß-catenin, CD44 and EGFR were observed in the tumors induced by KRT17 knockdown OSCC cells. CONCLUSIONS: A novel miRNA-485-5p/KRT17/integrin/FAK/Src/ERK/ß-catenin signaling pathway is unveiled to modulate OSCC cancer stemness and drug resistance to the common first-line chemotherapeutics. This provides a potential new therapeutic strategy to inhibit OSCC stem cells and counter chemoresistance.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Queratina-17/metabolismo , MicroRNAs , Neoplasias Bucais , Animais , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Humanos , Integrina beta4/genética , Integrina beta4/metabolismo , Integrinas/genética , Integrinas/metabolismo , Integrinas/uso terapêutico , Queratina-17/genética , Queratina-17/farmacologia , Camundongos , MicroRNAs/farmacologia , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Plectina/genética , Plectina/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , beta Catenina/genética
9.
ACS Chem Neurosci ; 13(6): 766-775, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35230090

RESUMO

Polyphenols are the class of naturally synthesized compounds in the secondary metabolism of plants, which are widely distributed in fruits and vegetables. Their potential health treatment strategies have attracted wide attention in the scientific community. The abnormal aggregation of Aß to form mature fibrils is pathologically related to Alzheimer's disease (AD). Therefore, inhibiting Aß40 fibrillogenesis was considered to be the major method for the intervention and therapy of AD. Glycosides, as a cluster of natural phenolic compounds, are widely distributed in Chinese herbs, fruits, and vegetables. The inhibitory effect of glycosides (phloridzin, salidroside, polydatin, geniposide, and gastrodin) and their corresponding small molecules (phloretin, 4-hydroxyphenyl ethanol, resveratrol, genipin, and 4-hydroxybenzyl alcohol) on Aß40 aggregation and fibrils prolongation, disaggregation against mature fibrils, and the resulting cytotoxicity were studied by systematical biochemical, cell biology and molecular docking techniques, respectively. As a result, all inhibitors were observed against Aß40 aggregation and fibrils prolongation and disaggregated mature Aß40 fibrils in a dose-dependent manner. Besides, the cell validity experiments also showed that all inhibitors could effectively alleviate the cytotoxicity induced by Aß40 aggregates, and the glycoside groups played important roles in this inhibiting process. Finally, molecular docking was performed to study the interactions between these inhibitors and Aß40. Docking showed that all inhibitors were bound to the similar region of Aß40, and glycoside group formed hydrogen bonds with the pivotal residues Lys16. These results indicated that the glycoside groups could increase the inhibitory effects and reduce cytotoxicity. Glycosides have tremendous potential to be developed as an innovative type of aggregation inhibitor to control and treat neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Peptídeos beta-Amiloides/química , Glicosídeos/farmacologia , Humanos , Ligação de Hidrogênio , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/química
10.
J Hazard Mater ; 428: 128262, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35051771

RESUMO

Organophosphorus pesticides (OPs) detection has attracted considerable attention because of the extensive application of OPs. In this research, non-toxic and high-performance metalloenzyme mimics of Zn2+-bonding peptides were developed by obtaining inspiration from phosphotriesterase (PTE) and nanofiber formation. Furthermore, based on the electrochemical activity of p-nitrophenol (PNP), the electrochemical sensor of metalloenzyme mimics was developed. By examining the effect of the active sites of peptides and fibril formation on the degradation of OPs, the optimal metalloenzyme mimic was selected. Furthermore, optimal metalloenzyme mimics were combined with NiCo2O4 to develop an electrochemical sensor of OPs. By monitoring square wave voltammetry (SWV) signals of PNP degraded from OPs, the amounts of OPs in actual samples could be determined in 15 min. We discovered that both the active sites of α metal and ß metal were required for metalloenzyme mimics; Zn2+ promoted peptide fibrosis and especially acted as a cofactor for degrading OPs. Compared to traditional methods, the electrochemical sensor of metalloenzyme mimics was sensitive, reliable, and non-toxic; furthermore, the detection limit of methyl paraoxon was as low as 0.08 µM. The metalloenzyme mimics will be a promising material for detecting OPs in the food industry and environment fields.


Assuntos
Técnicas Biossensoriais , Metaloproteínas , Praguicidas , Compostos Organofosforados , Peptídeos
11.
Autophagy ; 18(4): 921-934, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34470575

RESUMO

ABBREVIATIONS: ATG14: autophagy related 14; CDH2: cadherin 2; ChIP-qPCR: chromatin immunoprecipitation quantitative polymerase chain reaction; CQ: chloroquine; ECAR: extracellular acidification rate; EMT: epithelial-mesenchymal transition; EPCAM: epithelial cell adhesion molecule; MAP1LC3A/LC3A: microtubule associated protein 1 light chain 3 alpha; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAP1LC3C/LC3C: microtubule associated protein 1 light chain 3 gamma; NDUFV2: NADH:ubiquinone oxidoreductase core subunit V2; OCR: oxygen consumption rate; ROS: reactive oxygen species; RT-qPCR: reverse-transcriptase quantitative polymerase chain reaction; SC: scrambled control; shRNA: short hairpin RNA; SNAI2: snail family transcriptional repressor 2; SOX2: SRY-box transcription factor 2; SQSTM1/p62: sequestosome 1; TGFB/TGF-ß: transforming growth factor beta; TOMM20: translocase of outer mitochondrial membrane 20; ZEB1: zinc finger E-box binding homeobox 1.


Assuntos
Autofagia , Neoplasias Pulmonares , Autofagia/fisiologia , Plasticidade Celular , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
12.
J Hazard Mater ; 403: 123873, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264945

RESUMO

Di(2-ethylhexyl) phthalate (DEHP), the most abundantly used plasticizer, was considered to be a hazardous chemical that was difficult to be degraded naturally. In this study, inspired by the "catalytic triad'' in serine proteases, an enzyme mimic material was developed by combining the proteases's active sites of serine, histidine and aspartate (S-H-D) with the self-assembling sequence of LKLKLKL and the aromatic group of fluorenylmethyloxycarbonyl (Fmoc). By mixing the monomer of peptides containing separate S, H and D residues with a ratio of 2:1:1, the enzyme mimics were found to co- assemble into nanofibers (Co-HSD) and showed the highest activity towards DEHP degradation because of the synergistic effects of active sites, orderly secondary structure and stable molecular conformation. To further improve ability and applicability, the high active mimetic enzyme was immobilized onto regenerated cellulose (RC) membranes for DEHP degradation in a continuous recycling mode. The RC membranes were first functionalized by the NaIO4 oxidation method to form aldehyde groups and then conjugated with the enzyme mimics via Schiff-base reaction. As a biocatalytic membrane, this membrane could not only effectively degrade DEHP, but also showed good stability, thus establishing a promising biomaterial for large scale biodegradation of DEHP in water decontamination and liquid food depollution.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Biodegradação Ambiental , Plastificantes
13.
J Mater Chem B ; 8(41): 9601-9609, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33006351

RESUMO

Enzyme mimics have been developed by imitating and incorporating specific features of native enzymes to achieve catalytic activity, and are expectedly comparable to that of native enzymes. Here, inspired by the "catalytic triad" in serine proteases, a series of peptide-based enzyme mimics were designed to follow the rational design principle of peptides via self-assembly, and were further applied in the degradation of di(2-ethylhexyl)phthalate (DEHP). The relationship of the structure of enzyme mimics with their degradation activity was analyzed by transmission electron microscopy, fluorescence spectroscopy, circular dichroism, Raman spectroscopy, X-ray diffraction spectroscopy, and computational modeling. These results show that the hydrophobic skeleton, amino acid sequence, species, and periodic distribution have important effects on the structure of the peptide sequence and the number of hydrogen bonds; in addition, pH can also affect the self-assembly characteristics of peptides and the formation of stable fibers, which are all closely linked to the catalytic activity of the enzyme mimics. The self-assembled peptides had a stable fibrous morphology and secondary structure after the DEHP degradation assay. The enzyme mimics with high catalytic activity constructed from the self-assembled peptides may provide guidance for the future degradation of DEHP in food packaging or water treatment, and also give insights into the design of enzyme mimics in other related fields.


Assuntos
Dietilexilftalato/metabolismo , Poluentes Ambientais/metabolismo , Peptídeos/metabolismo , Plastificantes/metabolismo , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Domínio Catalítico , Células HeLa , Humanos , Modelos Moleculares , Células PC12 , Peptídeos/química , Ratos , Serina Proteases/química , Serina Proteases/metabolismo
14.
Analyst ; 145(20): 6683-6690, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-32812541

RESUMO

Methylammonium lead halide perovskite quantum dots (MAPB-QDs) have been widely used for photovoltaic devices due to their special electronic structures. In this work, MAPB-QDs were used for the first time to detect polar organochlorine pesticides (OCPs) based on the phenomenon that the fluorescence spectra of MAPB-QDs were blue-shifted in the presence of polar OCPs. Furthermore, 1H NMR, FTIR, XPS and XRD were performed first to illustrate the sensing mechanism. In the presence of polar OCPs, the MAPB-QDs' capping ligands, oleic acid (OA) and oleylamine (OAm), were replaced with OCPs and then the chlorine element was adequately doped into QDs, resulting in the increase of the MAPB-QDs' bandgap. As result of the insufficient stability of MAPB-QDs in the presence of moisture, MAPB-QDs were mixed with PDMS and used as the colorimetric cards for fast detection of OCPs in real samples.

15.
J Agric Food Chem ; 68(33): 8788-8796, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32700906

RESUMO

The aggregation of amyloid-ß protein (Aß) is deemed a vital pathological feature of Alzheimer's disease (AD). Hence, inhibiting Aß aggregation is noticed as a major tactic for the prevention and therapy of AD. Hydroxycinnamic acid, as a natural phenolic compound, is widely present in plant foods and has several biological activities including anti-inflammation, antioxidation, and neuroprotective effects. Here, it was found that hydroxycinnamic acid and its structural analogues (3-hydroxycinnamic acid, 2-hydroxycinnamic acid, cinnamic acid, 3,4-dihydroxycinnamic acid, 2,4-dihydroxycinnamic acid, and 3,4,5-trihydroxycinnamic acid) could inhibit Aß40 fibrillogenesis and reduce Aß40-induced cytotoxicity in a dose-dependent manner. Among these small molecules investigated, 3,4,5-trihydroxycinnamic acid is considered to be the most effective inhibitor, which reduces the ThT fluorescence intensity to 30.79% and increases cell viability from 49.47 to 84.78% at 200 µM. Also, the results with Caenorhabditis elegans verified that these small molecules can ameliorate AD-like symptoms of worm paralysis. Moreover, molecular docking studies showed that these small molecules interact with the Aß40 mainly via hydrogen bonding. These results suggest that hydroxycinnamic acid and its structural analogues could inhibit Aß40 fibrillogenesis and the inhibition activity is enhanced with the increase of phenolic hydroxyl groups of inhibitors. These small molecules have huge potential to be developed into novel aggregation inhibitors in neurodegenerative disorders.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/toxicidade , Ácidos Cumáricos/administração & dosagem , Ácidos Cumáricos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Zea mays/química , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Animais , Caenorhabditis elegans , Sobrevivência Celular/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular
16.
J Food Drug Anal ; 28(4): 486-507, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35696140

RESUMO

As the highly toxic pollutants will seriously harm human health, it is particularly important to establish the analysis and detection technology of food pollutants. Compared with the traditional detection methods, fluorescent detection techniques based on nanomaterials trigger wide interesting because of reduced detection time, simple operation, high sensitivity and selectivity, and economic. In this review, the application of fluorescent sensors in food pollutants detection is presented. Firstly, conventional fluorescent nanomaterials including metal-based quantum dots, carbon dots, graphene quantum dots and metal nanoclusters were summarized, with emphasis on the photoluminescence mechanism. Then, the fluorescence sensors based on these nanomaterials for food pollutants detection were discussed, involving in the established methods, sensor mechanisms, sensitivity, selectivity, and practicability of fluorescence sensors. The selected analytes focus on five types of higher toxic food pollutants, including mycotoxins, foodborne pathogens, pesticide residues, antibiotic residues, and heavy metal ions. Finally, outlook on the future and potential development of fluorescence detection technology in the field of food science were proposed, including green synthesis and reusability of fluorescence probes, large-scale industrialization of sensors, nondestructive testing of samples and degradation of harmful substances.

17.
ACS Omega ; 4(19): 18428-18433, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31720546

RESUMO

Genistin and its aglycone genistein of isoflavone are naturally occurring in plants. The aim of this study is to develop an experimental animal model of enterohepatic circulation to investigate the metabolic biotransformation of genistin and genistein in rats. A paired-rat model was developed in which the drug was administered intravenously to the donor rat whose bile duct was cannulated into the duodenum of the untreated recipient rat. The blood sample was collected from the jugular vein of the donor and recipient rats after genistin administration. The results demonstrate that genistein was detected in both the donor and recipient rats after genistein administration (50 mg/kg, iv) in the donor rat, which suggested that the enterohepatic circulation of genistein occurred. The same phenomenon happened again in the biotransformation after genistin administration (50 mg/kg, iv) in the donor rat. Genistein was detected in the recipient rat's blood sample after treatment with ß-glucuronidase, which suggested that enzymatic hydrolysis occurred in the transformation of genistin into genistein. In conclusion, the research revealed the metabolic pathway of the glucuronidation of genistin into genistein.

18.
Sci Rep ; 9(1): 16922, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729427

RESUMO

AXL is expressed in many types of cancer and promotes cancer cell survival, metastasis and drug resistance. Here, we focus on identifying modulators that regulate AXL at the mRNA level. We have previously observed that the AXL promoter activity is inversely correlated with the AXL expression levels, suggesting that post-transcriptional mechanisms exist that down-regulate the expression of AXL mRNA. Here we show that the RNA binding protein PTBP1 (polypyrimidine tract-binding protein) directly targets the 5'-UTR of AXL mRNA in vitro and in vivo. Moreover, we also demonstrate that PTBP1, but not PTBP2, inhibits the expression of AXL mRNA and the RNA recognition motif 1 (RRM1) of PTBP1 is crucial for this interaction. To clarify how PTBP1 regulates AXL expression at the mRNA level, we found that, while the transcription rate of AXL was not significantly different, PTBP1 decreased the stability of AXL mRNA. In addition, over-expression of AXL may counteract the PTBP1-mediated apoptosis. Knock-down of PTBP1 expression could enhance tumor growth in animal models. Finally, PTBP1 was found to be negatively correlated with AXL expression in lung tumor tissues in Oncomine datasets and in tissue micro-array (TMA) analysis. In conclusion, we have identified a molecular mechanism of AXL expression regulation by PTBP1 through controlling the AXL mRNA stability. These findings may represent new thoughts alternative to current approaches that directly inhibit AXL signaling and may eventually help to develop novel therapeutics to avoid cancer metastasis and drug resistance.


Assuntos
Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Regulação da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteínas Proto-Oncogênicas/genética , Estabilidade de RNA , RNA Mensageiro/genética , Receptores Proteína Tirosina Quinases/genética , Regiões 5' não Traduzidas , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Expressão Gênica , Genes Reporter , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Receptor Tirosina Quinase Axl
19.
ACS Chem Neurosci ; 10(11): 4633-4642, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31637909

RESUMO

The abnormal aggregation of amyloid beta (Aß or A beta) from monomeric proteins into amyloid fibrils is an important pathological contact to Alzheimer's disease (AD). Amyloid beta 40 (Aß40), the pivotal biomarker of AD, aggregates to form amyloid plaques. For this reason, inhibition of amyloid fibrillation had become a crucial prevention and therapeutic strategy. Usually, LVFFA is the central hydrophobic fragment of Aß and can inhibit the aggregation of Aß40. In this work, in order to improve the inhibitory ability of LVFFA, hexapeptide CLVFFA were conjugated at the surface of Au clusters (AuNCs) to manufacture a nanosized inhibitor, AuNCs-CLVFFA. Thioflavin T fluorescence and transmission electron microscope results showed that AuNCs-CLVFFA inhibited Aß40 fibrillogenesis, fibrils' prolongation, and mature fibrils' disaggregation. Furthermore, AuNCs as the backbone of the inhibitor showed extraordinary inhibition ability for Aß40 aggregation at a low AuNCs-CLVFFA concentration. Free hexapeptide CLVFFA, at the same concentration, showed almost no inhibition. Additionally, the inhibitor could maintain the optical properties of nanoclusters, and the cell viability demonstrated that the inhibitor had good biocompatibility and may potentially be applied into AD therapy or treatment.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Amiloide/efeitos dos fármacos , Amiloide/metabolismo , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Fragmentos de Peptídeos/metabolismo , Agregados Proteicos/efeitos dos fármacos , Peptídeos beta-Amiloides/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Ouro/química , Humanos , Nanopartículas Metálicas/química , Células PC12 , Fragmentos de Peptídeos/antagonistas & inibidores , Agregados Proteicos/fisiologia , Ratos
20.
Anal Chem ; 90(15): 9060-9067, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29973046

RESUMO

In this work, highly photoluminescent (PL) self-assembled copper nanoclusters (Cu NCs) capable of rapid, sensitive, and selective detection of histamine were developed. Cu NCs were synthesized in facile conditions by using 2,3,5,6-tetrafluorothiophenol (TFTP) as both the reducing agent and the protecting ligand, which exhibited intense saffron yellow (590 nm) PL via self-assembled induced emission (SAIE), and the absolute quantum yield (QY) of assembly was as high as 43.0%. The size, electronic states, and morphologies of the assembled nanoribbons were characterized, and the geometric structure and spectral properties of the Cu NCs were investigated by theoretical study. Furthermore, the mechanism of the excellent sensing performance of Cu NCs toward histamine was demonstrated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDX). With this sensing system, the amount of histamine in fish, shrimp, and red wine were analyzed, and experiment results verified the application of the sensor. Importantly, the luminescent test strips based on Cu NCs were fabricated for colorimetric detection of histamine in foods. This proposed technique may provide an alternative to traditional methods for histamine detection.


Assuntos
Cobre/química , Análise de Alimentos/métodos , Histamina/análise , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Animais , Colorimetria/métodos , Limite de Detecção , Modelos Moleculares , Fenóis/química , Substâncias Redutoras/química , Alimentos Marinhos/análise , Compostos de Sulfidrila/química , Atum/metabolismo , Vinho/análise
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