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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 322: 124765, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39018670

RESUMO

Excessive use of gentamicin sulfate can cause severe nephrotoxicity and ototoxicity, abnormal levels of Fe3+ intake can also cause serious damage to body. Therefore, establishing a fast and accurate detection method for the above-mentioned substances is of great significance. However, traditional detection methods such as high-performance liquid chromatography still have certain problems such as high cost and complex operation. Fluorescent MOFs are favored by analysts due to their high specific surface area, high porosity, adjustable pore size, and good stability. In this paper, we have synthesized four rare earth MOFs based on the pyridinecarboxylic acid ligand (H2L), which are [Eu(L)1/2H2O]n, [Gd(L)1/2H2O]n, [Sm(L)1/2H2O]n, [Y(L)3/2H2O·DMF]n. The structures of four MOFs were confirmed by single crystal X-ray diffraction, which proved that MOF-1, MOF-2 and MOF-3 were isostructural, and all the four MOFs were three-dimensional structures. In the fluorescence test, gentamicin sulfate and Fe3+ can cause significant fluorescence quenching of MOF-1 and MOF-4 respectively, and show good selectivity and anti-interference performance, as well as low detection limit and wide detection range. This work may provide a possibility for the detection of gentamicin sulfate and iron ions in complex environments.

2.
Front Biosci (Landmark Ed) ; 29(6): 217, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38940047

RESUMO

BACKGROUND: Although umbilical cord mesenchymal stem cell (UCMSC) infusion has been proposed as a promising strategy for the treatment of acute lung injury (ALI), the parameters of UCMSC transplantation, such as infusion routes and doses, need to be further optimized. METHODS: In this study, we compared the therapeutic effects of UCMSCs transplanted via intravenous injection and intratracheal instillation on lipopolysaccharide-induced ALI using a rat model. Following transplantation, levels of inflammatory factors in serum; neutrophils, total white blood cells, and lymphocytes in bronchoalveolar lavage fluid (BALF); and lung damage levels were analyzed. RESULTS: The results indicated that UCMSCs administered via both intravenous and intratracheal routes were effective in alleviating ALI, as determined by analyses of arterial blood gas, lung histopathology, BALF contents, and levels of inflammatory factors. Comparatively, the intratracheal instillation of UCMSCs was found to result in lower levels of lymphocytes and total proteins in BALF, whereas greater reductions in the serum levels of tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) were detected in rats receiving intravenously injected stem cells. CONCLUSIONS: Our findings in this study provide convincing evidence to indicate the efficacy of UCMSC therapy in the treatment of ALI mediated via different delivery routes, thereby providing a reliable theoretical basis for further clinical studies. Moreover, these findings imply that the effects obtained using the two assessed delivery routes for UCMSC transplantation are mediated via different mechanisms, which could be attributable to different cellular or molecular targets.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Transplante de Células-Tronco Mesenquimais , Ratos Sprague-Dawley , Cordão Umbilical , Animais , Lesão Pulmonar Aguda/terapia , Lesão Pulmonar Aguda/induzido quimicamente , Transplante de Células-Tronco Mesenquimais/métodos , Cordão Umbilical/citologia , Ratos , Masculino , Líquido da Lavagem Broncoalveolar/citologia , Células-Tronco Mesenquimais/citologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo , Injeções Intravenosas
3.
J Ethnopharmacol ; 318(Pt A): 116890, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37423514

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Marveled at the discovery of artemisinin, the world's expectations for traditional Chinese medicine are rising. He's Yangchao formula (HSYC) is a traditional Chinese herbal formula with the effects of tonifying kidney and essence, and reconciling yin and yang. It has been clinically proven to have anti-ovarian aging effects. Age is the primary cause of diminished ovarian reserve and assisted reproductive failure in women, whether HSYC has the potential to improve in vitro maturation of oocytes from advanced maternal age (AMA) mice has yet to be determined. AIM OF THE STUDY: This study aims to evaluate the efficacy and possible mechanism of HSYC in promoting in vitro maturation of oocytes from AMA mice. MATERIALS AND METHODS: The GV oocytes were obtained from young and aged mice. The GV oocytes from young mice were cultured in drops of M16 medium, and the GV oocytes from AMA mice were randomly divided four groups: Vehicle group (cultured in 90% M16 medium +10% blank serum), Low HSYC group (cultured in 90% M16 medium + 10% Low HSYC-medicated serum), High-HSYC group (cultured in 90% M16 medium +10% High HSYC-medicated serum), and Quercetin group (cultured in M16 medium supplemented with 10 µM quercetin). The rates of first polar body extrusion, reactive oxygen species (ROS), intracellular calcium, and mitochondrial membrane potential levels in each groups were observed. In addition, expression levels of mitochondrial function, autophagy, DNA damage, and antioxidant-related proteins were assessed. RESULTS: Supplementation of HSYC in vitro alleviated age-associated meiotic progression defects in maternally aged oocytes. Importantly, HSYC supplementation eliminated the age-related ROS accumulation to suppress DNA damage and autophagy during the in vitro maturation of maternally aged oocytes. Meanwhile, the mitochondrial function was improved after HSYC treatment, as manifested by higher mitochondrial membrane potential and lower Ca2+ levels. Furthermore, we found that HSYC supplementation during in vitro maturation of maternally aged oocytes upregulated the expression level of SIRT3, a crucial protein in regulating mitochondrial function. Consistently, the expression levels of the SOD2, PCG1α, and TFAM were increased, while the SOD2 acetylation level was decreased, which further proved its antioxidant function. CONCLUSIONS: HSYC supplementation promotes in vitro maturation of oocytes from AMA mice mainly via improving mitochondrial function and alleviating oxidative stress. The mechanism may be related to the regulation of SIRT3-dependent deacetylation of the SOD2 pathway.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Sirtuína 3 , Feminino , Animais , Camundongos , Idade Materna , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Quercetina/farmacologia , Oócitos
4.
J Zhejiang Univ Sci B ; 24(3): 262-268, 2023 Mar 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36916001

RESUMO

Endometrial cancer is the most common gynecological malignancy, affecting up to 3% of women at some point during their lifetime (Morice et al., 2016; Li and Wang, 2021). Based on the pathogenesis and biological behavioral characteristics, endometrial cancer can be divided into estrogen-dependent (I) and non-estrogen-dependent (II) types (Ulrich, 2011). Type I accounts for approximately 80% of cases, of which the majority are endometrioid carcinomas, and the remaining are mucinous adenocarcinomas (Setiawan et al., 2013). It is generally recognized that long-term stimulation by high estrogen levels with the lack of progesterone antagonism is the most important risk factor; meanwhile, there is no definite conclusion on the specific pathogenesis. The incidence of endometrial cancer has been on the rise during the past two decades (Constantine et al., 2019; Gao et al., 2022; Luo et al., 2022). Moreover, the development of assisted reproductive technology and antiprogestin therapy following breast cancer surgery has elevated the risk of developing type I endometrial cancer to a certain extent (Vassard et al., 2019). Therefore, investigating the influence of estrogen in type I endometrial cancer may provide novel concepts for risk assessment and adjuvant therapy, and at the same time, provide a basis for research on new drugs to treat endometrial cancer.


Assuntos
Neoplasias da Mama , Neoplasias do Endométrio , Feminino , Humanos , Proteínas Proto-Oncogênicas c-akt , Fosfatidilinositol 3-Quinases , Estrogênios , DNA Helicases
5.
Environ Geochem Health ; 45(7): 4867-4881, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36959429

RESUMO

The use of solid fuels for heating and cooking in rural Northeast China has led to severe indoor metal element pollution in particulate matter (PM), posing a direct threat to human health and creating immense pressure on the sustainability of residential environments. To investigate the levels, sources, and potential health hazards of indoor metal element pollution in this region, we conducted a year-long sampling and monitoring campaign in actual residential settings and used ICP-OES to measure six metal elements (Mn, Cr, Zn, Cu, Pb, and Ni). This study's findings reveal that indoor metal element pollution levels in PM (33,513.65 mg/kg per year) are higher in rural Northeast China compared to other rural areas. Straw burning is the primary source of metal element pollution, followed by motor vehicle emissions and natural soil sources. It is crucial to note that our results indicate a total carcinogenic risk greater than 10-4 according to the US EPA health risk model assessment, highlighting the high risk posed to human health by indoor metal elements in rural areas. By using a seriously polluted area in Northeast China as a case study, this research provides initial insights into the characteristics and sources of indoor metal pollution in rural areas, offering a reference for future prevention and control of indoor pollution in these regions. Ultimately, this work can help improve the rural habitat and enhance the health of the rural population.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Humanos , Material Particulado/análise , Monitoramento Ambiental/métodos , Poluição do Ar em Ambientes Fechados/análise , População Rural , Metais , China , Medição de Risco , Poluentes Atmosféricos/análise
6.
Inorg Chem ; 62(5): 2236-2243, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36689619

RESUMO

Two zero-dimensional inorganic-organic hybrids, namely, [C4mim][Cd(TCDPPA)3] (1) and [C4mpy][Cd(TCDPPA)3] (2), where (TCDPPA)- = 2,2,2-trichloro-N-(di(pyrrolidin-1-yl)phosphoryl)acetamide, (C4mim)+ = 1-butyl-3-methylimidazolium, and (C4mpy)+ = 1-butyl-4-methylpyridinium, have been synthesized via metathesis reactions and characterized systematically. These ionic cadmium-containing inorganic-organic hybrid compounds are assembled from a bulky organic cation and a complex anion constructed from the chelation of three TCDPPA ligands to one cadmium ion. These compounds possess wide band gaps and emit in the deep-blue region intensely with a quantum yield as high as 34.04%. The success of this work provides a new method for the design and fabrication of high-efficiency blue-emitting materials.

7.
iScience ; 23(10): 101630, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33103072

RESUMO

Understanding the mechanisms for cellular aging is a fundamental question in biology. Normal red blood cells (RBCs) survive for approximately 100 days, and their survival is likely limited by functional decline secondary to cumulative damage to cell constituents, which may be reflected in altered metabolic capabilities. To investigate metabolic changes during in vivo RBC aging, labeled cell populations were purified at intervals and assessed for abundance of metabolic intermediates using mass spectrometry. A total of 167 metabolites were profiled and quantified from cell populations of defined ages. Older RBCs maintained ATP and redox charge states at the cost of altered activity of enzymatic pathways. Time-dependent changes were identified in metabolites related to maintenance of the redox state and membrane structure. These findings illuminate the differential metabolic pathway usage associated with normal cellular aging and identify potential biomarkers to determine average RBC age and rates of RBC turnover from a single blood sample.

8.
Luminescence ; 35(7): 1142-1150, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32436363

RESUMO

In this study, a rhodamine-acetylferrocene conjugate of RBFc was synthesized and then characterized using spectroscopy and single-crystal analysis. The chemosensor RBFc exhibited a marked colour change from colourless to pink after binding to Cu2+ ions. Importantly, under the presence of the other competing cations in aqueous solution, only Cu2+ ions caused spirolactam ring opening in rhodamine B in RBFc, resulting in an enhanced absorbance of ultraviolet light spectra and fluorescence spectra, as well as obvious shifts in cyclic voltammetry curves and differential pulsed voltammetry curves. The novel probe described in this manuscript provides an attractive approach for detecting Cu2+ in the presence of other multisignals.


Assuntos
Eletroquímica , Corantes Fluorescentes , Água , Íons , Rodaminas , Espectrometria de Fluorescência
9.
Proc Natl Acad Sci U S A ; 117(5): 2432-2440, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31964827

RESUMO

The three-dimensional (3D) crystal structures of the GAF3 domain of cyanobacteriochrome Slr1393 (Synechocystis PCC6803) carrying a phycocyanobilin chromophore could be solved in both 15-Z dark-adapted state, Pr, λmax = 649 nm, and 15-E photoproduct, Pg, λmax = 536 nm (resolution, 1.6 and 1.86 Å, respectively). The structural data allowed identifying the large spectral shift of the Pr-to-Pg conversion as resulting from an out-of-plane rotation of the chromophore's peripheral rings and an outward movement of a short helix formed from a formerly unstructured loop. In addition, a third structure (2.1-Å resolution) starting from the photoproduct crystals allowed identification of elements that regulate the absorption maxima. In this peculiar form, generated during X-ray exposition, protein and chromophore conformation still resemble the photoproduct state, except for the D-ring already in 15-Z configuration and tilted out of plane akin the dark state. Due to its formation from the photoproduct, it might be considered an early conformational change initiating the parental state-recovering photocycle. The high quality and the distinct features of the three forms allowed for applying quantum-chemical calculations in the framework of multiscale modeling to rationalize the absorption maxima changes. A systematic analysis of the PCB chromophore in the presence and absence of the protein environment showed that the direct electrostatic effect is negligible on the spectral tuning. However, the protein forces the outer pyrrole rings of the chromophore to deviate from coplanarity, which is identified as the dominating factor for the color regulation.


Assuntos
Proteínas de Bactérias/química , Fotorreceptores Microbianos/química , Ficobilinas/química , Ficocianina/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Luz , Modelos Moleculares , Processos Fotoquímicos , Fotorreceptores Microbianos/metabolismo , Ficobilinas/metabolismo , Ficocianina/metabolismo , Conformação Proteica , Domínios Proteicos , Relação Estrutura-Atividade , Synechocystis/química , Synechocystis/metabolismo
10.
Dalton Trans ; 49(12): 3809-3815, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-31820767

RESUMO

A series of lanthanide diphosphonates, namely Ln(HL)(H2O)2 (Ln = Nd 1, Eu 2, Tb 3 and Er 4), have been synthesized from a semirigid diphosphonate ligand, (5-methyl-1,3-phenylene)bis(methylene)bisphosphonic acid (H4L). These lanthanide diphosphonates have been systematically characterized by using powder and single-crystal X-ray diffraction, elemental analysis, TGA, IR, UV-vis absorption and luminescence techniques. The single-crystal XRD measurements revealed that these compounds all have two-dimensional layered crystal structures. Among these four compounds, 1, 2 and 4 are isostructural and crystallize in the P21/c space group, whereas compound 3 crystallizes in the P21 space group. These compounds display the characteristic emissions of the respective lanthanide ions. The sensing properties of compound 3 were investigated which revealed that it could be used as a luminescent probe for Fe3+ and Cr2O72- with good selectivity and sensitivity.

11.
Transl Oncol ; 13(1): 32-41, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760267

RESUMO

BACKGROUND: Escaping cell death pathways is an important event during carcinogenesis. We previously identified anti-TNFα-induced apoptosis (ATIA, also known as vasorin) as an antiapoptotic factor that suppresses reactive oxygen species (ROS) production. However, the role of vasorin in lung carcinogenesis has not been investigated. METHODS: Vasorin expression was examined in human lung cancer tissues with immunohistochemistry and database analysis. Genetic and pharmacological approaches were used to manipulate protein expression and autophagy activity in human bronchial epithelial cells (HBECs). ROS generation was measured with fluorescent indicator, apoptosis with release of lactate dehydrogenase, and cell transformation was assessed with colony formation in soft agar. RESULTS: Vasorin expression was increased in human lung cancer tissues and cell lines, which was inversely associated with lung cancer patient survival. Cigarette smoke extract (CSE) and benzo[a]pyrene diol epoxide (BPDE)-induced vasorin expression in HBECs. Vasorin knockdown in HBECs significantly suppressed CSE-induced transformation in association with enhanced ROS accumulation and autophagy. Scavenging ROS attenuated autophagy and cytotoxicity in vasorin knockdown cells, suggesting that vasorin potentiates transformation by impeding ROS-mediated CSE cytotoxicity and improving survival of the premalignant cells. Suppression of autophagy effectively inhibited CSE-induced apoptosis, suggesting that autophagy was pro-apoptotic in CSE-treated cells. Importantly, blocking autophagy strongly potentiated CSE-induced transformation. CONCLUSION: These results suggest that vasorin is a potential lung cancer-promoting factor that facilitates cigarette smoke-induced bronchial epithelial cell transformation by suppressing autophagy-mediated apoptosis, which could be exploited for lung cancer prevention.

12.
Transl Oncol ; 13(2): 372-382, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31887632

RESUMO

INTRODUCTION: The efficacy of chemotherapeutic agents in killing cancer cells is mainly attributed to the induction of apoptosis. However, the tremendous efforts on enhancing apoptosis-related mechanisms have only moderately improved lung cancer chemotherapy, suggesting that other cell death mechanisms such as necroptosis could be involved. In this study, we investigated the role of the necroptosis pathway in the responsiveness of nonsmall cell lung cancer (NSCLC) to chemotherapy. METHODS: In vitro cell culture and in vivo xenograft tumor therapy models and clinical sample studies are combined in studying the role of necroptosis in chemotherapy and mechanism of necroptosis suppression involving RIP3 expression regulation. RESULTS: While chemotherapeutic drugs were able to induce necroptotic cell death, this pathway was suppressed in lung cancer cells at least partly through downregulation of RIP3 expression. Ectopic RIP3 expression significantly sensitized lung cancer cells to the cytotoxicity of anticancer drugs such as cisplatin, etoposide, vincristine, and adriamycin. In addition, RIP3 suppression was associated with RIP3 promoter methylation, and demethylation partly restored RIP3 expression and increased chemotherapeutic-induced necroptotic cell death. In a xenograft tumor therapy model, ectopic RIP3 expression significantly sensitized anticancer activity of cisplatin in vivo. Furthermore, lower RIP3 expression was associated with worse chemotherapy response in NSCLC patients. CONCLUSION: Our results indicate that the necroptosis pathway is suppressed in lung cancer through RIP3 promoter methylation, and reactivating this pathway should be exploited for improving lung cancer chemotherapy.

13.
ACS Synth Biol ; 8(4): 744-757, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30901519

RESUMO

The precise spatiotemporal regulation of protein synthesis is essential for many complex biological processes such as memory formation, embryonic development, and tumor formation. Current methods used to study protein synthesis offer only a limited degree of spatiotemporal control. Optogenetic methods, in contrast, offer the prospect of controlling protein synthesis noninvasively within minutes and with a spatial scale as small as a single synapse. Here, we present a hybrid yeast system where growth depends on the activity of human eukaryotic initiation factor 4E (eIF4E) that is suitable for screening optogenetic designs for the down-regulation of protein synthesis. We used this system to screen a diverse initial panel of 15 constructs designed to couple a light switchable domain (PYP, RsLOV, AsLOV, Dronpa) to 4EBP2 (eukaryotic initiation factor 4E binding protein 2), a native inhibitor of translation initiation. We identified cLIPS1 (circularly permuted LOV inhibitor of protein synthesis 1), a fusion of a segment of 4EBP2 and a circularly permuted version of the LOV2 domain from Avena sativa, as a photoactivated inhibitor of translation. Adapting the screen for higher throughput, we tested small libraries of cLIPS1 variants and found cLIPS2, a construct with an improved degree of optical control. We show that these constructs can both inhibit translation in yeast harboring a human eIF4E in vivo, and bind human eIF4E in vitro in a light-dependent manner. This hybrid yeast system thus provides a convenient way for discovering optogenetic constructs that can regulate human eIF4E-dependent translation initiation in a mechanistically defined manner.


Assuntos
Fator de Iniciação 4E em Eucariotos/genética , Optogenética/métodos , Iniciação Traducional da Cadeia Peptídica/genética , Biossíntese de Proteínas/genética , Saccharomyces cerevisiae/genética , Regulação para Baixo/genética , Humanos , Ligação Proteica/genética
14.
Natl Sci Rev ; 6(1): 5-7, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34691819
15.
Int J Nanomedicine ; 13: 5937-5952, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30323584

RESUMO

BACKGROUND: The Traditional Chinese Medicine, arsenic trioxide (ATO, As2O3) could inhibit growth and induce apoptosis in a variety of solid tumor cells, but it is severely limited in the treatment of glioma due to its poor BBB penetration and nonspecifcity distribution in vivo. PURPOSE: The objective of this study was encapsulating ATO in the modified PAMAM den-drimers to solve the problem that the poor antitumor effect of ATO to glioma, which provide a novel angle for the study of glioma treatment. METHODS: The targeting drug carrier (RGDyC-mPEG-PAMAM) was synthesized based on Arg-Gly-Asp (RGDyC) and αvß3 integrin targeting ligand, and conjugated to PEGylated fifth generation polyamidoamine dendrimer (mPEG-PAMAM). It was characterized by nuclear magnetic resonance, fourier transform infrared spectra, Nano-particle size-zeta potential analyzer,etc. The in vitro release characteristics were studied by dialysis bag method. MTT assay was used to investigate the cytotoxicity of carriers and the antitumor effect of ATO formulation. In vitro blood-brain barrier (BBB) and C6 cell co-culture models were established to investigate the inhibitory effect of different ATO formulation after transporting across BBB. Pharmacokinetic and antitumor efficacy studies were investigated in an orthotopic murine model of C6 glioma. RESULTS: The prepared RGDyC-mPEG-PAMAM was characterized for spherical dendrites, comparable size (21.60±6.81 nm), and zeta potential (5.36±0.22 mV). In vitro release showed that more ATO was released from RGDyC-mPEG-PAMAM/ATO (79.5%) at pH 5.5 than that of pH 7.4, during 48 hours. The cytotoxicity of PEG-modified carriers was lower than that of the naked PAMAM on both human brain microvascular endothelial cells and C6 cells. In in vitro BBB model, modification of RGDyC heightened the cytotoxicity of ATO loaded on PAMAM, due to an increased uptake by C6 cells. The results of cell cycle and apoptosis analysis revealed that RGDyC-mPEG-PAMAM/ATO arrested the cell cycle in G2-M and exhibited threefold increase in percentage of apoptosis to that in the PEG-PAMAM/ATO group. Compared with ATO-sol group, both RGDyC-mPEG-PAMAM/ATO and mPEG-PAMAM/ATO groups prolonged the half-life time, increased area under the curve, and improved antitumor effect, significantly. While the tumor volume inhibitory of RGDyC-mPEG-PAMAM/ATO was 61.46±12.26%, it was approximately fourfold higher than the ATO-sol group, and twofold to the mPEG-PAMAM/ATO group. CONCLUSION: In this report, RGDyC-mPEG-PAMAM could enhance the antitumor of ATO to glioma, it provides a desirable strategy for targeted therapy of glioma.


Assuntos
Arsenicais/uso terapêutico , Dendrímeros/química , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Oligopeptídeos/química , Óxidos/uso terapêutico , Polietilenoglicóis/química , Animais , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Arsenicais/administração & dosagem , Arsenicais/farmacocinética , Arsenicais/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Glioma/patologia , Humanos , Masculino , Camundongos , Óxidos/administração & dosagem , Óxidos/farmacocinética , Óxidos/farmacologia , Coelhos , Ratos , Eletricidade Estática , Resultado do Tratamento
16.
ACS Synth Biol ; 7(10): 2355-2364, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30203962

RESUMO

Nature provides an array of proteins that change conformation in response to light. The discovery of a complementary array of proteins that bind only the light-state or dark-state conformation of their photoactive partner proteins would allow each light-switchable protein to be used as an optogenetic tool to control protein-protein interactions. However, as many photoactive proteins have no known binding partner, the advantages of optogenetic control-precise spatial and temporal resolution-are currently restricted to a few well-defined natural systems. In addition, the affinities and kinetics of native interactions are often suboptimal and are difficult to engineer in the absence of any structural information. We report a phage display strategy using a small scaffold protein that can be used to discover new binding partners for both light and dark states of a given light-switchable protein. We used our approach to generate binding partners that interact specifically with the light state or the dark state conformation of two light-switchable proteins: PYP, a test case for a protein with no known partners, and AsLOV2, a well-characterized protein. We show that these novel light-switchable protein-protein interactions can function in living cells to control subcellular localization processes.


Assuntos
Proteínas de Bactérias/metabolismo , Técnicas de Visualização da Superfície Celular/métodos , Luz , Fotorreceptores Microbianos/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/metabolismo , Humanos , Proteínas Imobilizadas/química , Proteínas Imobilizadas/metabolismo , Espectroscopia de Ressonância Magnética , Fotorreceptores Microbianos/química , Fotorreceptores Microbianos/genética , Conformação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
17.
Inorg Chem ; 57(17): 10694-10701, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30113819

RESUMO

A facile reversed-phase microemulsion method was used to synthesize shell-core nanospheres of SiO2@RCs (SiO2-encapsuled rare-earth metal complexes). ß-d-Galactose was then grafted onto the surfaces of the nanospheres through the copper(I)-catalyzed azide-alkyne cycloaddition click reaction for targeted delivery. The chemical characteristics and surface profiles of the nanocarriers were investigated by Fourier transform infrared spectroscopy, dynamic light scattering, transmission electron microscopy, and scanning electron microscopy. A high-efficiency microwave synthesis method was applied to prepare five complex cores by the reaction of different rare-earth metal salts with two isomeric ligands, o-CPA (2-chlorophenoxyacetic acid) and m-CPA (3-chlorophenoxyacetic acid). The crystal structures of the five synthesized RC cores were confirmed through X-ray diffraction, which revealed the formulas of five RCs, [Dy( o-CPA)3(H2O)]·H2O RC1, [Ho( o-CPA)3(H2O)]·H2O RC2, 2[Er( m-CPA)3(H2O)]·3H2O RC3, 2[Gd( m-CPA)3(H2O)]·3H2O RC4, and [Ce2( m-CPA)6(H2O)3]·2H2O RC5. An in vitro cell study revealed that all RCs exhibited certain anticancer activities. RC2, in particular, showed the strongest cytotoxicity against HepG2 cells. The enhanced cell permeability and drug retention considerably improved the cytotoxicity of all SiO2@RC2-gal relative to that of RC2. The selective uptake of the ß-d-galactose-conjugated nanospheres by HepG2 cells through mechanisms mediated by cell surface receptors resulted in fewer side effects on extrahepatic tissues. Our contribution provides a novel design concept of a target SiO2@RCs-gal nanocarrier for delivering affordable antitumor complexes in cancer therapy.


Assuntos
Técnicas de Química Analítica/métodos , Química Click , Complexos de Coordenação/química , Sistemas de Liberação de Medicamentos , Galactose/química , Nanosferas/química , Dióxido de Silício/química , Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Ácido 2,4-Diclorofenoxiacético/química , Antineoplásicos/química , Catálise , Cristalografia por Raios X , Células Hep G2 , Humanos , Modelos Biológicos , Estrutura Molecular , Difração de Raios X
18.
J Drug Target ; 26(1): 86-94, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28635335

RESUMO

Glioma is the most common primary malignant brain tumour and the effect of chemotherapy is hampered by low permeability across the blood-brain-barrier (BBB). Borneol is a time-honoured 'Guide' drug in traditional Chinese medicine and has been proved to be capable of promoting free drugs into the brain efficiently, but there are still risks that free drugs, especially anti-glioma drugs, may be disassembled and metabolised before penetrating the BBB and caused the whole brain distribution. The purpose of this paper was to investigate whether borneol intervention could facilitate the BBB penetration and assist glioma treatment by combining with doxorubicin (DOX) loaded PAMAM dendrimers drug delivery system modified with Angiopep-2 (a ligand of the low-density lipoprotein receptor-related protein, which overexpress both in the BBB and gliomas). The results demonstrated that Angiopep-2 modification could actually enhance the affinity between the dendrimers and the targeting cells and finally increase the cell uptake and boost the anti-tumour ability. Borneol physical combination could further enhance the anti-tumour efficiency of this targeting drug delivery system (TDDS) after penetrating BBB. Compared with free DOX solution, this TDDS illustrated obviously sustained and pH-dependent drug release. This suggested that this synergetic strategy provided a promising way for glioma therapy.


Assuntos
Canfanos/química , Dendrímeros/química , Doxorrubicina/uso terapêutico , Glioma/tratamento farmacológico , Peptídeos/química , Encéfalo/irrigação sanguínea , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Células Endoteliais , Humanos
19.
Dalton Trans ; 46(44): 15424-15433, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29082408

RESUMO

Mesoporous silica core-shell nanospheres encapsulating a rare-earth metal complex (RC) were first synthesised through a facile W/O (water in oil) inverse microemulsion method. In order to achieve targeted complex delivery, folic acid (FA) was used as the targeting component due to its high affinity for over-expressed folate receptors (FRs) in cancer cells. The RC2@SiO2-FA nanospheres were characterised via ultraviolet-visible light absorption spectroscopy (UV-vis spectroscopy), dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A microwave method was used to synthesise five RC cores based on 4-chlorophenoxyacetic acid, and their crystal structures were further confirmed using X-ray diffraction. The five RC cores have the following chemical formulae: [Er2(p-CPA)6(H2O)6] RC1, [Ho2(p-CPA)6(H2O)6] RC2, [Sm(p-CPA)3(H2O)] RC3, [Pr(p-CPA)3(H2O)]·3H2O RC4 and [Ce(p-CPA)3(H2O)2]·2H2O RC5. The carboxyl groups showed two kinds of coordination modes, namely µ2-η1:η1 and µ2-η1:η2, among RC1-RC5. The flexible -OCH2COO- spacer group, which can undergo rotation of its C-O and C-C bonds, offered great potential for structural diversity. In vivo experiments revealed that the nanospheres exhibited no obvious cytotoxicity on HepG2 cells and 293 T cells, even at concentrations of up to 80 µg mL-1. Nevertheless, all of the RC cores showed a certain degree of anti-tumour efficacy; in particular, RC2 showed the strongest cytotoxicity against HepG2 cells. Interestingly, the cytotoxicity of all of the RC2@SiO2-FA nanospheres was higher than that of lone RC2. These types of FA-targeted mesoporous silica nanocarriers can be used for the delivery of anti-tumour RC, and provide a basis for the further study of affordable non-platinum-based complexes.


Assuntos
Complexos de Coordenação/química , Portadores de Fármacos/química , Metais Terras Raras/química , Nanopartículas/química , Nanosferas/química , Dióxido de Silício/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Ácido Fólico/química , Células HEK293 , Células Hep G2 , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Conformação Molecular , Nanosferas/toxicidade , Porosidade , Espectrometria de Fluorescência
20.
Carcinogenesis ; 38(6): 604-614, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472347

RESUMO

Mucin 1 (MUC1) is a tumor antigen that is aberrantly overexpressed in various cancers, including lung cancer. Our previous in vitro studies showed that MUC1 facilitates carcinogen-induced EGFR activation and transformation in human lung bronchial epithelial cells (HBECs), which along with other reports suggests an oncogenic property for MUC1 in lung cancer. However, direct evidence for the role of MUC1 in lung carcinogenesis is lacking. In this study, we used the 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced A/J mouse lung tumor model to investigate the effect of whole-body Muc1 knockout (KO) on carcinogen-induced lung carcinogenesis. Surprisingly, lung tumor multiplicity was significantly increased in Muc1 KO compared to wild-type (WT) mice. The EGFR/AKT pathway was unexpectedly activated, and expression of the EGFR ligand epiregulin (EREG) was increased in the lung tissues of the Muc1 KO compared to the WT mice. EREG stimulated proliferation and protected against cigarette smoke extract (CSE)-induced cytotoxicity in in vitro cultured human bronchial epithelial cells. Additionally, we determined that MUC1 was expressed in human fibroblast cell lines where it suppressed CSE-induced EREG production. Further, suppression of MUC1 cellular activity with GO-201 enhanced EREG production in lung cancer cells, which in turn protected cancer cells from GO-201-induced cell death. Moreover, an inverse association between MUC1 and EREG was detected in human lung cancer, and EREG expression was inversely associated with patient survival. Together, these results support a promiscuous role of MUC1 in lung cancer development that may be related to cell-type specific functions of MUC1 in the tumor microenvironment, and MUC1 deficiency in fibroblasts and malignant cells results in increased EREG production that activates the EGFR pathway for lung carcinogenesis.


Assuntos
Transformação Celular Neoplásica/patologia , Epirregulina/metabolismo , Receptores ErbB/metabolismo , Neoplasias Pulmonares/patologia , Mucina-1/fisiologia , Animais , Carcinógenos/toxicidade , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Epirregulina/genética , Receptores ErbB/genética , Retroalimentação Fisiológica , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nitrosaminas/toxicidade , Fumar/efeitos adversos
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