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1.
Nucleic Acids Res ; 52(4): 1878-1895, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153123

RESUMO

The exonuclease ISG20L2 has been initially characterized for its role in the mammalian 5.8S rRNA 3' end maturation, specifically in the cleavage of ITS2 of 12S precursor ribosomal RNA (pre-rRNA). Here, we show that human ISG20L2 is also involved in 18S pre-rRNA maturation through removing the ITS1 region, and contributes to ribosomal biogenesis and cell proliferation. Furthermore, we determined the crystal structure of the ISG20L2 nuclease domain at 2.9 Å resolution. It exhibits the typical αßα fold of the DEDD 3'-5' exonuclease with a catalytic pocket located in the hollow near the center. The catalytic residues Asp183, Glu185, Asp267, His322 and Asp327 constitute the DEDDh motif in ISG20L2. The active pocket represents conformational flexibility in the absence of an RNA substrate. Using structural superposition and mutagenesis assay, we mapped RNA substrate binding residues in ISG20L2. Finally, cellular assays revealed that ISG20L2 is aberrantly up-regulated in colon adenocarcinoma and promotes colon cancer cell proliferation through regulating ribosome biogenesis. Together, these results reveal that ISG20L2 is a new enzymatic member for 18S pre-rRNA maturation, provide insights into the mechanism of ISG20L2 underlying pre-rRNA processing, and suggest that ISG20L2 is a potential therapeutic target for colon adenocarcinoma.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Animais , Humanos , RNA Ribossômico 18S/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Adenocarcinoma/genética , Neoplasias do Colo/genética , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Processamento Pós-Transcricional do RNA , Exonucleases/genética , Exonucleases/metabolismo , RNA Ribossômico 5,8S/genética , Mamíferos/genética
2.
EMBO J ; 40(2): e104542, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33264433

RESUMO

Optimal DNA damage response is associated with ADP-ribosylation of histones. However, the underlying molecular mechanism of DNA damage-induced histone ADP-ribosylation remains elusive. Herein, using unbiased mass spectrometry, we identify that glutamate residue 141 (E141) of variant histone H2AX is ADP-ribosylated following oxidative DNA damage. In-depth studies performed with wild-type H2AX and the ADP-ribosylation-deficient E141A mutant suggest that H2AX ADP-ribosylation plays a critical role in base excision repair (BER). Mechanistically, ADP-ribosylation on E141 mediates the recruitment of Neil3 glycosylase to the sites of DNA damage for BER. Moreover, loss of this ADP-ribosylation enhances serine-139 phosphorylation of H2AX (γH2AX) upon oxidative DNA damage and erroneously causes the accumulation of DNA double-strand break (DSB) response factors. Taken together, these results reveal that H2AX ADP-ribosylation not only facilitates BER repair, but also suppresses the γH2AX-mediated DSB response.


Assuntos
ADP-Ribosilação/genética , Difosfato de Adenosina/metabolismo , Histonas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Cromatina/metabolismo , Quebras de DNA de Cadeia Dupla , Dano ao DNA/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HCT116 , Células HEK293 , Humanos , Fosforilação/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo
3.
EMBO Rep ; 24(9): e56230, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37489617

RESUMO

Fibrillarin (FBL) is a highly conserved nucleolar methyltransferase responsible for methylation of ribosomal RNA and proteins. Here, we reveal a role for FBL in DNA damage response and its impact on cancer proliferation and sensitivity to DNA-damaging agents. FBL is highly expressed in various cancers and correlates with poor survival outcomes in cancer patients. Knockdown of FBL sensitizes tumor cells and xenografts to DNA crosslinking agents, and leads to homologous recombination-mediated DNA repair defects. We identify Y-box-binding protein-1 (YBX1) as a key interacting partner of FBL, and FBL increases the nuclear accumulation of YBX1 in response to DNA damage. We show that FBL promotes the expression of BRCA1 by increasing the binding of YBX1 to the BRCA1 promoter. Our study sheds light on the regulatory mechanism of FBL in tumorigenesis and DNA damage response, providing potential therapeutic targets to overcome chemoresistance in cancer.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Neoplasias/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Antineoplásicos/uso terapêutico , Dano ao DNA , Linhagem Celular Tumoral , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismo , Proteína BRCA1/genética
4.
Nucleic Acids Res ; 51(14): 7649-7665, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37334830

RESUMO

Nucleic acid ADP-ribosylation has been established as a novel modification found in a wide diversity of prokaryotic and eukaryotic organisms. tRNA 2'-phosphotransferase 1 (TRPT1/TPT1/KptA) possesses ADP-ribosyltransferase (ART) activity and is able to ADP-ribosylate nucleic acids. However, the underlying molecular mechanism remains elusive. Here, we determined crystal structures of TRPT1s in complex with NAD+ from Homo sapiens, Mus musculus and Saccharomyces cerevisiae. Our results revealed that the eukaryotic TRPT1s adopt common mechanisms for both NAD+ and nucleic acid substrate binding. The conserved SGR motif induces a significant conformational change in the donor loop upon NAD+ binding to facilitate the catalytic reaction of ART. Moreover, the nucleic acid-binding residue redundancy provides structural flexibility to accommodate different nucleic acid substrates. Mutational assays revealed that TRPT1s employ different catalytic and nucleic acid-binding residues to perform nucleic acid ADP-ribosylation and RNA 2'-phosphotransferase activities. Finally, cellular assays revealed that the mammalian TRPT1 is able to promote endocervical HeLa cell survival and proliferation. Together, our results provide structural and biochemical insights into the molecular mechanism of TRPT1 for nucleic acid ADP-ribosylation.


Assuntos
Fosfotransferases (Aceptor do Grupo Álcool) , Proteínas de Saccharomyces cerevisiae , Animais , Humanos , Camundongos , Adenosina Difosfato Ribose/metabolismo , ADP Ribose Transferases/genética , ADP Ribose Transferases/metabolismo , ADP-Ribosilação , Células HeLa , NAD/metabolismo , Ácidos Nucleicos/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/química , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
5.
J Biochem Mol Toxicol ; 38(4): e23684, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38533528

RESUMO

Lung cancer is the leading cause of cancer-related deaths worldwide. Circular RNA (circRNA) circ_0088036 is a recently discovered circRNA known for its roles in rheumatoid arthritis. The study aimed to study the function of circ_0088036 in lung adenocarcinoma (LUAD). Circ_0088036 expressions were analyzed in the Gene Expression Omnibus (GEO) database. The relationship between circ_0088036 expressions and clinicopathological data of LUAD was assessed. The messenger RNA and protein levels were analyzed by quantitative real-time polymerase chain reaction and Western blot. Cell viability, apoptosis, and invasion were tested by Cell Counting Kit-8, flow cytometry, and transwell assay. The direct interaction between microRNA-203 (miR-203) and circ_0088036 or specificity protein 1 (SP1) was confirmed by dual-luciferase reporter assay, RNA pull-down, and RNA immunoprecipitation assays. Circ_0088036 was overexpressed in LUAD from the analysis of the GEO database. The poor prognosis was found in the patients with high expressions of circ_0088036. The level of Circ_0088036 was increased in LUAD tissues and cells. In terms of function, the deletion of circ_0088036 inhibited LUAD tumorigenesis in vitro by repressing cell growth, invasion, and epithelial-mesenchymal transition (EMT). In mechanism, circ_0088036 could competitively sponge miR-203, thereby affecting the expressions of the target gene SP1. In addition, lessening of miR-203 and enlarging of SP1 could eliminate the anticancer effect of short hairpin RNA-circ_0088036 on LUAD cells. Besides, the knockout of circ_0088036 hindered the growth of xenografted tumors in vivo. Circ_0088036 promoted the LUAD cell growth, invasion, and EMT via modulating the miR-203/SP1 axis in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Humanos , Linhagem Celular Tumoral , Proliferação de Células , RNA Circular
6.
Langmuir ; 39(26): 9069-9077, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37358076

RESUMO

A Dioscorea opposita Thunb polysaccharide (DOP)-modified ZIF8 material was developed in this study, which can be used as a "smart" glucose-responsive carrier to control the slow release of drugs. The 3-aminophenylboronic acid (APBA) functionalized carboxylated long-chain polymer poly(ethylene glycol) (PEG) segments, which were first modified on the surface of ZIF8 nanoparticles with a hydrogen bond and then chemically cross-linked with DOP through a borate ester bond, leading to the drugs loaded on ZIF8 being "closed" in PBS but being "open" via taking off the DOP coating in high concentrations of glucose; thus, leakage can be prevented in the drug loaded and a glucose-triggered release can effectively result. Moreover, the materials showed good biocompatibility and the released trans-N-p-coumaroyltyramine (NCT) could work synergistically with the DOP to improve insulin resistance and promote glucose consumption in insulin-resistant HepG2 cells.


Assuntos
Dioscorea , Glucose , Dioscorea/química , Polissacarídeos/química , Insulina
7.
Proc Natl Acad Sci U S A ; 117(7): 3621-3626, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32024762

RESUMO

Ten-eleven translocation (TET) family enzymes (TET1, TET2, and TET3) oxidize 5-methylcytosine (5mC) and generate 5-hydroxymethylcytosine (5hmC) marks on the genome. Each TET protein also interacts with specific binding partners and partly plays their role independent of catalytic activity. Although the basic role of TET enzymes is well established now, the molecular mechanism and specific contribution of their catalytic and noncatalytic domains remain elusive. Here, by combining in silico and biochemical screening strategy, we have identified a small molecule compound, C35, as a first-in-class TET inhibitor that specifically blocks their catalytic activities. Using this inhibitor, we explored the enzymatic function of TET proteins during somatic cell reprogramming. Interestingly, we found that C35-mediated TET inactivation increased the efficiency of somatic cell programming without affecting TET complexes. Using high-throughput mRNA sequencing, we found that by targeting 5hmC repressive marks in the promoter regions, C35-mediated TET inhibition activates the transcription of the BMP-SMAD-ID signaling pathway, which may be responsible for promoting somatic cell reprogramming. These results suggest that C35 is an important tool for inducing somatic cell reprogramming, as well as for dissecting the other biological functions of TET enzymatic activities without affecting their other nonenzymatic roles.


Assuntos
Reprogramação Celular , Proteínas de Ligação a DNA/antagonistas & inibidores , Dioxigenases/antagonistas & inibidores , Inibidores Enzimáticos/química , Proteínas Proto-Oncogênicas/antagonistas & inibidores , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Domínio Catalítico , Linhagem Celular , Reprogramação Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/química , Dioxigenases/genética , Dioxigenases/metabolismo , Humanos , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
8.
Int Wound J ; 20(2): 302-312, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35801278

RESUMO

We performed a meta-analysis to evaluate the effect of chronic obstructive pulmonary disease on surgical site wound infection, and other postoperative problems after coronary artery bypass grafting. A systematic literature search up to April 2022 was performed and 37 444 subjects with coronary artery bypass grafting at the baseline of the studies; 4320 of them were with the chronic obstructive pulmonary disease, and 33 124 were without chronic obstructive pulmonary disease. Odds ratio (OR), and mean difference (MD) with 95% confidence intervals (CIs) were calculated to assess the effect of chronic obstructive pulmonary disease on surgical site wound infection, and other postoperative problems after coronary artery bypass grafting using the dichotomous, and contentious methods with a random or fixed-effect model. The chronic obstructive pulmonary disease subjects had a significantly higher surgical site wound infection (OR, 1.27; 95% CI, 1.01-1.60, P = 0.04), respiratory failure (OR, 1.84; 95% CI, 1.55-2.18, P < 0.001), mortality (OR, 1.61; 95% CI, 1.37-1.89, P < 0.001), pneumonia (OR, 2.30; 95% CI, 1.97-2.68, P < 0.001), pleural effusion (OR, 1.78; 95% CI, 1.12-2.83, P = 0.02), stroke (OR, 1.99; 95% CI, 1.17-3.36, P = 0.01), and length of intensive care unit stay (MD, 0.73; 95% CI, 0.19-1.26, P = 0.008) after coronary artery bypass grafting compared with subjects without chronic obstructive pulmonary disease. However, chronic obstructive pulmonary disease subjects did not show any significant difference in length of hospital stay (MD, 0.83; 95% CI, -0.01 to 1.67, P = 0.05), and pneumothorax (OR, 1.59; 95% CI, 0.98-2.59, P = 0.06) after coronary artery bypass grafting compared with subjects without chronic obstructive pulmonary disease. The chronic obstructive pulmonary disease subjects had a significantly higher surgical site wound infection, respiratory failure, mortality, pneumonia, pleural effusion, stroke, and length of intensive care unit stay, and no significant difference in length of hospital stay, and pneumothorax after coronary artery bypass grafting compared with subjects without chronic obstructive pulmonary disease. The analysis of outcomes should be with caution because of the low sample size of 1 out of 11 studies in the meta-analysis and a low number of studies in certain comparisons.


Assuntos
Doença da Artéria Coronariana , Derrame Pleural , Pneumotórax , Doença Pulmonar Obstrutiva Crônica , Insuficiência Respiratória , Acidente Vascular Cerebral , Humanos , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Derrame Pleural/complicações , Pneumotórax/complicações , Complicações Pós-Operatórias/etiologia , Doença Pulmonar Obstrutiva Crônica/cirurgia , Doença Pulmonar Obstrutiva Crônica/complicações , Insuficiência Respiratória/complicações , Acidente Vascular Cerebral/etiologia , Infecção da Ferida Cirúrgica , Resultado do Tratamento
9.
Nucleic Acids Res ; 48(6): 3001-3013, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31965183

RESUMO

Nucleosomal histones are barriers to the DNA repair process particularly at DNA double-strand breaks (DSBs). However, the molecular mechanism by which these histone barriers are removed from the sites of DNA damage remains elusive. Here, we have generated a single specific inducible DSB in the cells and systematically examined the histone removal process at the DNA lesion. We found that histone removal occurred immediately following DNA damage and could extend up to a range of few kilobases from the lesion. To examine the molecular mechanism underlying DNA damage-induced histone removal, we screened histone modifications and found that histone ADP-ribosylation was associated with histone removal at DNA lesions. PARP inhibitor treatment suppressed the immediate histone eviction at DNA lesions. Moreover, we examined histone chaperones and found that the FACT complex recognized ADP-ribosylated histones and mediated the removal of histones in response to DNA damage. Taken together, our results reveal a pathway that regulates early histone barrier removal at DNA lesions. It may also explain the mechanism by which PARP inhibitor regulates early DNA damage repair.


Assuntos
Dano ao DNA/genética , Reparo do DNA/genética , Histonas/genética , Poli ADP Ribosilação/genética , ADP-Ribosilação/genética , Núcleo Celular/genética , Cromatina/genética , Cromossomos Humanos X/genética , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Células HCT116 , Humanos , Chaperonas Moleculares/genética , Nucleossomos/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia
10.
J Enzyme Inhib Med Chem ; 37(1): 2540-2550, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36120953

RESUMO

In this work, a highly effective separation approach mediated by 5-Lipoxygenase (5-LOX) was established for screening and isolation of anti-inflammatory ingredients from leaves of Lonicera japonica Thunb. (LLJT). Using 5-LOX immobilised on TiO2 nanotubes as a microreactor, the targeted screening was exploited by combining with HPLC-MS system. Four compounds confirmed as luteolin, luteoside, lonicerin, and isochlorogenic acid C and a fraction (M1) were screened out to be potent inhibitors of 5-LOX. Their anti-inflammatory activities were further investigated and confirmed by RAW 264.7 cells inflammation model and rat foot swelling model. Furthermore, M1 was prepared by MCI GEL CHP20P column chromatography, and further separated by Pre-HPLC. One new compound confirmed to be 5,7,3',4'-tetrahydroxyflavone-7-O-sambubioside was first isolated from LLJT. The results provide a new method for the effective separation of active components derived from natural products.HighlightsA 5-LOX mediated separation method was established for isolation of anti-inflammatory compounds.An anti-inflammatory ingredient was separated by MCI GEL CHP20P column chromatography.One new compound was first isolated from leaves of Lonicera japonica Thunb.5-LOX was immobilised on TiO2 nanotubes and exploited by combining with HPLC-MS system.The anti-inflammatory activity of screened components was evaluated. [Figure: see text].


Assuntos
Lonicera , Nanotubos , Animais , Anti-Inflamatórios/farmacologia , Araquidonato 5-Lipoxigenase , Lonicera/química , Luteolina , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Titânio
11.
Int J Mol Sci ; 23(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36012342

RESUMO

A novel hydrogel (DOP/PEI-PBA) based on the "three-component" reaction of 2-formylphenylboric acid (2-FPBA), the primary amine group of polyethyleneimine (PEI) and the cis-o-dihydroxy groups of Dioscorea opposita Thunb polysaccharide (DOP) was designed in this work. The hydrogel can be easily prepared by simply mixing the three reactants at room temperature. The hydrogel had dual responsiveness to glucose and pH, and can realize the controllable release of insulin. Moreover, the hydrogel combining insulin and DOP can inhibit the reactive oxygen species (ROS) level and malondialdehyde (MDA) content, and promote glucose consumption as well as the level of superoxide dismutase (SOD), in high-glucose-induced injury in HL-7702 cells, which reflects the synergistic effect of insulin and DOP to protect hepatocytes from oxidative stress at the same time. Further in vitro cytotoxicity studies showed that the hydrogel had good biocompatibility and no obvious toxicity to cells. These indicate that the prepared hydrogel (DOP/PEI-PBA) can be expected to be applied in the clinical treatment of insulin deficiency in diabetes.


Assuntos
Dioscorea , Preparações de Ação Retardada , Carboidratos da Dieta , Glucose , Hidrogéis/farmacologia , Insulina , Insulina Regular Humana , Polissacarídeos/química , Polissacarídeos/farmacologia
12.
J Biol Chem ; 295(40): 13838-13849, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-32753484

RESUMO

The ADP-ribosylhydrolase ARH3 plays a key role in DNA damage repair, digesting poly(ADP-ribose) and removing ADP-ribose from serine residues of the substrates. Specific inhibitors that selectively target ARH3 would be a useful tool to examine DNA damage repair, as well as a possible strategy for tumor suppression. However, efforts to date have not identified any suitable compounds. Here, we used in silico and biochemistry screening to search for ARH3 inhibitors. We discovered a small molecule compound named ARH3 inhibitor 26 (AI26) as, to our knowledge, the first ARH3 inhibitor. AI26 binds to the catalytic pocket of ARH3 and inhibits the enzymatic activity of ARH3 with an estimated IC50 of ∼2.41 µm in vitro Moreover, hydrolysis of DNA damage-induced ADP-ribosylation was clearly inhibited when cells were pretreated with AI26, leading to defects in DNA damage repair. In addition, tumor cells with DNA damage repair defects were hypersensitive to AI26 treatment, as well as combinations of AI26 and other DNA-damaging agents such as camptothecin and doxorubicin. Collectively, these results reveal not only a chemical probe to study ARH3-mediated DNA damage repair but also a chemotherapeutic strategy for tumor suppression.


Assuntos
Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Glicosídeo Hidrolases/metabolismo , Linhagem Celular Tumoral , Glicosídeo Hidrolases/genética , Humanos
13.
J Asian Nat Prod Res ; 23(12): 1189-1196, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33327766

RESUMO

This work obtained and identified pterocephanoside A (1), one new iridoid glucoside derivative with rare structure of three iridoid glycosides linked to cyclopenta[c]pyran-3(1H)-one, and 10 known iridoids (2-11) from Pterocephalus hookeri through silica gel column chromatography and semi-preparative HPLC. The structure of the new compound was confirmed by 1D and 2D NMR and HRMS data analysis. Compounds 1 and 2 were isolated from this plant for the first time. The iridoids mostly possessed seco-iridoid subtype and iridoid subtype skeletons from P. hookeri. Compounds 1, 3, 4, and 6-11 showed weak anti-inflammatory activity.


Assuntos
Caprifoliaceae , Medicina Tradicional Tibetana , Glicosídeos Iridoides , Iridoides , Estrutura Molecular
14.
J Biol Chem ; 293(37): 14470-14480, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30045870

RESUMO

ADP-ribosylation of proteins plays key roles in multiple biological processes, including DNA damage repair. Recent evidence suggests that serine is an important acceptor for ADP-ribosylation, and that serine ADP-ribosylation is hydrolyzed by ADP-ribosylhydrolase 3 (ARH3 or ADPRHL2). However, the structural details in ARH3-mediated hydrolysis remain elusive. Here, we determined the structure of ARH3 in a complex with ADP-ribose (ADPR). Our analyses revealed a group of acidic residues in ARH3 that keep two Mg2+ ions at the catalytic center for hydrolysis of Ser-linked ADP-ribosyl group. In particular, dynamic conformational changes involving Glu41 were observed in the catalytic center. Our observations suggest that Mg2+ ions together with Glu41 and water351 are likely to mediate the cleavage of the glycosidic bond in the serine-ADPR substrate. Moreover, we found that ADPR is buried in a groove and forms multiple hydrogen bonds with the main chain and side chains of ARH3 residues. On the basis of these structural findings, we used site-directed mutagenesis to examine the functional roles of key residues in the catalytic pocket of ARH3 in mediating the hydrolysis of ADP-ribosyl from serine and DNA damage repair. Moreover, we noted that ADPR recognition is essential for the recruitment of ARH3 to DNA lesions. Taken together, our study provides structural and functional insights into the molecular mechanism by which ARH3 hydrolyzes the ADP-ribosyl group from serine and contributes to DNA damage repair.


Assuntos
ADP-Ribosilação , Glicosídeo Hidrolases/metabolismo , Adenosina Difosfato Ribose/metabolismo , Sequência de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Dano ao DNA , Reparo do DNA , Ácido Glutâmico/metabolismo , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Células HEK293 , Humanos , Ligação de Hidrogênio , Hidrólise , Magnésio/metabolismo , Mutagênese Sítio-Dirigida , Conformação Proteica , Homologia de Sequência de Aminoácidos , Serina/metabolismo , Relação Estrutura-Atividade
15.
Biomacromolecules ; 20(5): 2148-2158, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-30995832

RESUMO

Poly(amidoamine) dendrimer (PAMAM) is well-known for its high efficiency as a drug delivery vehicle. However, the intrinsic cytotoxicity and lack of a detectable signal to facilitate tracking have impeded its practical applications. Herein, we have developed a novel label-free fluorescent and biocompatible PAMAM derivative by simple surface modification of PAMAM using acetaldehyde. The modified PAMAM possessed a strong green fluorescence, which was generated by the C=N bonds of the resulting Schiff Bases via n-π* transition, while the intrinsic cytotoxicity of PAMAM was simultaneously ameliorated. Through further PEGylation, the fluorescent PAMAM demonstrated excellent intracellular tracking in human melanoma SKMEL28 cells. In addition, our PEGylated fluorescent PAMAM derivative achieved enhanced loading and delivery efficiency of the anticancer drug doxorubicin (DOX) compared to the original PAMAM. Importantly, the accelerated kinetics of DOX-encapsulated fluorescent PAMAM nanocomposites in an acidic environment facilitated intracellular drug release, which demonstrated comparable cytotoxicity to that of the free-form doxorubicin hydrochloride (DOX·HCl) against melanoma cells. Overall, our label free fluorescent PAMAM derivative offers a new opportunity of traceable and controlled delivery for DOX and other drugs of potential clinical importance.


Assuntos
Antineoplásicos/administração & dosagem , Dendrímeros/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Nanocompostos/química , Poliaminas/química , Acetaldeído/química , Antineoplásicos/química , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Corantes Fluorescentes/química , Células HEK293 , Humanos , Nanocompostos/toxicidade , Polietilenoglicóis/química , Bases de Schiff/química
16.
Fish Shellfish Immunol ; 94: 99-112, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476388

RESUMO

The lack of practical control measures for pharyngeal myxobolosis is becoming an important limiting factor for the sustainable development of the gibel carp (Carassius auratus gibelio) culture industry in China. Myxobolus honghuensis has been identified as the causative agent of this pandemic disease, which exclusively infects the pharynx of gibel carp, a potential important mucosal lymphoid-associated tissue (MLAT). Myxozoa generally initiate invasion through the mucosal tissues of fish, where some of them also complete their sporogonial stages. However, the pharynx-associated immune responses of teleost against myxosporeans infection remain unknown. Here, a de novo transcriptome assembly of the pharynx of gibel carp naturally infected with M. honghuensis was performed for the first time, using RNA-seq. Comparative analysis of severely infected and mildly infected pharyngeal tissues (SI group and MI group) from the same fish individuals and control pharyngeal tissues (C group) from the uninfected fish was carried out to investigate the potential mucosal immune function of the fish pharynx, and characterize the panoramic picture of pharynx local mucosal immune responses of gibel carp against the M. honghuensis infection. A total of 242,341 unigenes were obtained and pairwise comparison resulted in 13,009 differentially-expressed genes (DEGs) in the SI/C group comparison, 6014 DEGs in the MI/C group comparison, and 9031 DEGs in the SI/MI group comparison. Comprehensive analysis showed that M. honghuensis infection elicited a significant parasite load-dependent alteration of the expression of numerous innate and adaptive immune-related genes in the local lesion tissue. Innate immune molecules, including mucins, toll-like receptors, C-type lectin, serum amyloid A, cathepsins and complement components were significantly up-regulated in the SI group compared with the C group. Up-regulation of genes involved in apoptosis signaling pathway and the IFN-mediated immune system were found in the SI group, suggesting these two pathways played a crucial role in innate immune response to M. honghuensis infection. Up-regulation of chemokines and chemokine receptors and the induction of the leukocyte trans-endothelial migration pathways in the severely and mildly infected pharynx suggested that many leucocytes were recruited to the local infected sites to mount a strong mucosal immune responses against the myxosporean infection. Up-regulation of CD3D, CD22, CD276, IL4/13A, GATA3, arginase 2, IgM, IgT and pIgR transcripts provided strong evidences for the presence of T/B cells and specific mucosal immune responses at local sites with M. honghuensis infection. Our results firstly demonstrated the mucosal function of the teleost pharynx and provided evidences of intensive local immune defense responses against this mucosa-infecting myxosporean in the gibel carp pharynx. Pharyngeal myxobolosis was shaped by a prevailing anti-inflammatory response pattern during the advanced infection stages. Further understanding of the functional roles of fish immune molecules involved in the initial invasion and/or final sporogony site may facilitate future development of control strategies for this myxobolosis.


Assuntos
Doenças dos Peixes/imunologia , Carpa Dourada , Imunidade nas Mucosas , Myxobolus/fisiologia , Doenças Parasitárias em Animais/imunologia , Animais , Doenças dos Peixes/parasitologia , Doenças Parasitárias em Animais/parasitologia , Faringe/parasitologia , RNA-Seq/veterinária
17.
J Nanosci Nanotechnol ; 19(4): 2147-2153, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486958

RESUMO

Cellulose/graphene oxide composite membranes (CGCMs) were prepared using a vacuum-filtration method. The CGCMs were then used as filters to remove organic pollutants from wastewater. It was found that the CGCM filters could efficiently and simultaneously achieve wastewater treatment and adsorbent separation. Their adsorption of Rhodamine B (RhB, an organic dye) varied with varying cellulose/graphene oxide mass ratios. The CGCM obtained at a cellulose/graphene oxide mass ratio of 8:1 exhibited the maximum removal efficiency for RhB. The maximum adsorption capacity of the CGCMs for RhB was found to be 86.4 mg/g. In addition, the CGCMs were easily regenerated and the regenerated CGCMs retained good abilities to remove contaminants, which could be significant for their application in wastewater treatment.

18.
Environ Geochem Health ; 41(6): 2631-2648, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31076980

RESUMO

Understanding the changes in chemical composition of soil plays an important role in effective control of irrigation and fertilization in agricultural productions, which further protects the groundwater quality and predicts its evolution. Field trials were conducted from 2014 to 2016 to investigate the impacts of irrigation and fertilization on mineral composition transformation in the soil profile. Based on HYDRUS-HP1 and Visual MINTEQ, this paper simulated and computed the migration and transformation of chemical components during the irrigation and fertilization in the vadose zone soil of Jinghuiqu district. The results showed that when the nitrogen fertilizer entered the soil, the urea was hydrolyzed to NH4+ and it was nitrified as NO2-, which caused pH value to drop around the first 4 days after irrigation, and rise slightly on the 12th day. Due to the fact that soil belongs to calcareous soil, concentration of CaCO3 and other carbonates (Mg or Na in sodic soils) could buffer the soil pH well above 8.5. Thus, on the 30th day of the post-irrigation the pH reached the same level as it was before irrigation. The change in pH resulted in the main ions reacting, dissolving and precipitating simultaneously in the soil profile. The concentrations of Ca2+, Mg2+ and HCO3- had significant correlations with the increasing ammonia nitrogen hydrolyzed from urea, and this process is accompanied with the saturation index of minerals and the main ion content changing. At the same time, the varying temperature action on pH of the soil was higher in summer than that in winter. Thus, the irrigation, fertilization and temperature had affected pH and main chemical components in the soil.


Assuntos
Irrigação Agrícola , Fertilizantes , Solo/química , Irrigação Agrícola/métodos , Agricultura/métodos , Cálcio/análise , Carbonato de Cálcio/análise , Monitoramento Ambiental , Fertilizantes/análise , Concentração de Íons de Hidrogênio , Hidrólise , Magnésio/análise , Nitrogênio/análise , Nitrogênio/metabolismo , Estações do Ano , Ureia/química
19.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3151-3156, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31602866

RESUMO

"Qi medicinal herbs" in China refers to a kind of regional national folk herbs related to the treatment of five labors and seven injuries,the last word of which is "Qi". Our study is to sort out and standardize the name and basic confused varieties through the establishment of " Qi medicinal herbs" VFP information database. " Qi medicinal herbs" variety sorting model of " literature research-variety survey-data mining-spatial distribution" was developed by means of literature analysis which the names and varieties of " Qi medicinal herbs" in the literature were summarized and sorted out. The relationship between the distribution of " Qi medicinal herbs" resources and the use of ethnic groups were visualized by Cytoscape 2. 8. 0 software. The information database of " Qi medicinal herbs" involved in 230 kinds of medicinal materials which including 211 species of plants( including varieties) from 66 families. Medicinal materials standard in China have 9 kinds of " Qi medicinal herbs". Among them,there are 31 kinds of " Qi medicinal herbs" with the confusion of " the different names of the same" and " the different substance of the same names". The most used ethnic groups are Tujia,Qiang and Miao. The main efficacy is clearing heat and detoxification,dispelling wind and removing dampness,etc.,and the main treatment is for injury,rheumatic arthralgia and so on. Names and varieties of " Qi medicinal herbs" among Chinese ethnic groups and folk are standardized and sorted out,which is served to promotethe " Qi medicinal herbs" reasonable protection and utilization of resources,and provide effective reference for exploring the information technology and geographical distribution of ethnic medicine and standardizing clinical medication.


Assuntos
Medicamentos de Ervas Chinesas/normas , Plantas Medicinais/classificação , China , Humanos , Medicina Tradicional Chinesa , Qi , Terminologia como Assunto
20.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3157-3161, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31602867

RESUMO

In order to study the interaction between Pterocephalus hookeri and bitter taste receptors,three-dimensional structural models of bitter taste receptors TAS2 R16,TAS2 R14 and TAS2 R13 were established by homology modeling in this paper. Maestro software was used for docking the chemical constituents of P. hookeri with bitter taste receptors. The results showed that 25 chemical components of P. hookeri can regulate three bitter taste receptors. And these components were mainly iridoid glycosides and phenolic acids.This research focused on the comprehensive application of homology modeling and molecular docking technology to explore the interaction between bitter chemical constituents of P. hookeri and bitter taste receptors. This study provided assistance in revealing pharmacodynamic basis of bitter Tibetan medicine at molecular level. It also provided new ideas and methods for the study of Tibetan medicine.


Assuntos
Caprifoliaceae/química , Medicina Tradicional Tibetana , Simulação de Acoplamento Molecular , Receptores Acoplados a Proteínas G/metabolismo , Correlação de Dados , Humanos , Paladar
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