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1.
Int J Mol Sci ; 25(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38791374

RESUMO

Cryptococcus neoformans (C. neoformans) is a pathogenic fungus that can cause life-threatening meningitis, particularly in individuals with compromised immune systems. The current standard treatment involves the combination of amphotericin B and azole drugs, but this regimen often leads to inevitable toxicity in patients. Therefore, there is an urgent need to develop new antifungal drugs with improved safety profiles. We screened antimicrobial peptides from the hemolymph transcriptome of Blaps rhynchopetera (B. rhynchopetera), a folk Chinese medicine. We found an antimicrobial peptide named blap-6 that exhibited potent activity against bacteria and fungi. Blap-6 is composed of 17 amino acids (KRCRFRIYRWGFPRRRF), and it has excellent antifungal activity against C. neoformans, with a minimum inhibitory concentration (MIC) of 0.81 µM. Blap-6 exhibits strong antifungal kinetic characteristics. Mechanistic studies revealed that blap-6 exerts its antifungal activity by penetrating and disrupting the integrity of the fungal cell membrane. In addition to its direct antifungal effect, blap-6 showed strong biofilm inhibition and scavenging activity. Notably, the peptide exhibited low hemolytic and cytotoxicity to human cells and may be a potential candidate antimicrobial drug for fungal infection caused by C. neoformans.


Assuntos
Antifúngicos , Peptídeos Antimicrobianos , Besouros , Cryptococcus neoformans , Testes de Sensibilidade Microbiana , Cryptococcus neoformans/efeitos dos fármacos , Animais , Antifúngicos/farmacologia , Antifúngicos/química , Besouros/microbiologia , Besouros/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Humanos , Biofilmes/efeitos dos fármacos , Sequência de Aminoácidos
2.
Microbiol Spectr ; 11(3): e0308922, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37140456

RESUMO

Drug resistance against bacteria and fungi has become common in recent years, and it is urgent to discover novel antimicrobial peptides to manage this problem. Many antimicrobial peptides from insects have been reported to have antifungal activity and are candidate molecules in the treatment of human diseases. In the present study, we characterized an antifungal peptide named blapstin that was isolated from the Chinese medicinal beetle Blaps rhynchopetera used in folk medicine. The complete coding sequence was cloned from the cDNA library prepared from the midgut of B. rhynchopetera. It is a 41-amino-acid diapause-specific peptide (DSP)-like peptide stabilized by three disulfide bridges and shows antifungal activity against Candida albicans and Trichophyton rubrum with MICs of 7 µM and 5.3 µM, respectively. The C. albicans and T. rubrum treated with blapstin showed irregular and shrunken cell membranes. In addition, blapstin inhibited the activity of C. albicans biofilm and showed little hemolytic or toxic activity on human cells and it is highly expressed in the fat body, followed by the hemolymph, midgut, muscle, and defensive glands. These results indicate that blapstin may help insects fight against fungi and showed a potential application in the development of antifungal reagents. IMPORTANCE Candida albicans is one of the conditional pathogenic fungi causing severe nosocomial infections. Trichophyton rubrum and other skin fungi are the main pathogens of superficial cutaneous fungal diseases, especially in children and the elderly. At present, antibiotics such as amphotericin B, ketoconazole, and fluconazole are the main drugs for the clinical treatment of C. albicans and T. rubrum infections. However, these drugs have certain acute toxicity. Long-term use can increase kidney damage and other side effects. Therefore, obtaining broad-spectrum antifungal drugs with high efficiency and low toxicity for the treatment of C. albicans and T. rubrum infections is a top priority. Blapstin is an antifungal peptide which shows activity against C. albicans and T. rubrum. The discovery of blapstin provides a novel clue for our understanding of the innate immunity of Blaps rhynchopetera and provides a template for designing antifungal drugs.


Assuntos
Besouros , Dermatomicoses , Animais , Criança , Humanos , Idoso , Antifúngicos/uso terapêutico , Candida albicans , Testes de Sensibilidade Microbiana , Dermatomicoses/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos Antimicrobianos
3.
Mamm Genome ; 33(4): 654-671, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36173464

RESUMO

N6-methyladenosine (m6A) is the most abundant mRNA internal modification and has reportedly been linked to aerobic glycolysis, a hallmark event in tumor development. This work focuses on the role of the m6A methyltransferase WT1-associated protein (WTAP) in metabolic reprogramming and development of colon adenocarcinoma (COAD) and the molecules involved. The WTAP expression in COAD tissues and cells was detected. WTAP was knocked down in two COAD cell lines to figure out its role in the glycolytic activity and malignant phenotype of cancer cells. Cancer cells were further injected into nude mice subcutaneously or via tail vein to evaluate tumor growth and metastasis. The downstream molecules involved were explored using bioinformatics tools, and the molecular interactions were confirmed by immunoprecipitation, luciferase assays, and rescue experiments. WTAP was abundantly expressed in COAD samples. Knockdown of WTAP suppressed glucose consumption, lactate production, and glycolysis, which consequently suppressed cancer cell growth and dissemination in vitro and in vivo. WTAP promoted m6A methylation and stabilized forkhead box P3 (FOXP3) mRNA with the participation of the m6A "reader" YTHDF1. FOXP3 could further bind to SMARCE1 promoter for transcriptional activation. Rescue experiments showed that upregulation of FOXP3 or SMARCE1 restored the glycolytic activity in COAD cells and augmented the growth and mobility of cells both in vitro and in vivo. This study demonstrates that WTAP grants glycolytic activity to COAD and promotes tumor malignant development via the m6A modification of FOXP3 mRNA and the upregulation of SMARCE1.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Animais , Camundongos , Adenocarcinoma/genética , Neoplasias do Colo/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Glicólise/genética , Camundongos Nus , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Life Sci ; 278: 119603, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33984358

RESUMO

Multidrug resistance gene (MDR1a) and P-glycoprotein (P-gp) play an important role in the development of ulcerative colitis (UC) and influence the therapeutic effect of glucocorticoids, which may lead to drug resistance mechanically. UC may be related to miR-145 to some extent, and the relationship still needs further exploration. In this study we found that the expression of miR-145 was downregulated in the colonic tissues of rats with Dextran sodium sulfate (DSS)-induced UC. Also, the expression of MDR1a in colon tissues of each group negatively correlated with the expression of miR-145 in rats. The change in the plasma peak concentration (Cmax) in each group positively related to the miR-145 level. Mechanistically, miR-145 negatively regulated the expression and function of P-gp via acting directly on the 3'-UTR of MDR1 mRNA. Overall, these results indicated that miR-145 had a protective effect on the colorectal mucosa, and its downregulation may enhance the expression and function of MDR1a and P-gp, promoting the occurrence and development of UC. The downregulation of miR-145 reduced the drug sensitivity of 5-aminosalicylic acid (5-ASA) and glucocorticoids in treating UC, indicating that miR-145 might be a potential therapeutic target for UC.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Colite Ulcerativa/genética , MicroRNAs/genética , Regiões 3' não Traduzidas , Animais , Colite Ulcerativa/patologia , Regulação da Expressão Gênica , Genes MDR , Masculino , RNA Mensageiro/genética , Ratos Sprague-Dawley
5.
Am J Physiol Gastrointest Liver Physiol ; 318(4): G827-G839, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32174132

RESUMO

There is increasing evidence that microRNA (miRNA) abnormity is involved in the occurrence and the development of various malignancies, including colon cancer. MiRNA-524-5p has been reported to possess anticancer activity in various tumors, which function is seldom investigated in colon cancer cells. The aim of this study was to explore the effect of the miRNA-524-5p/with-no-lysine kinase 1 (WNK1) system on angiogenesis in a colon cancer cell line (HT-29 and COLO205 cells) and further investigate the potential mechanisms. We found miRNA-524-5p expression was relatively high in COLO205 cells and relatively low in HT-29 cells. Elevating miRNA-524-5p expression inhibited proliferation, induced cycle arrest, diminished vascular endothelial growth factor production, and thereby suppressed angiogenesis in HT-29 cells. WNK1 silencing exerted the ability of antiangiogenesis in HT-29 cells. Besides, miRNA-524-5p deficiency-induced angiogenesis was impeded by WNK1 silence in COLO205 cells. In a murine tumor model, miRNA-524-5p agomir treatment significantly suppressed colon cancer tumorigenicity with the downregulation of WNK1 expression. In summary, our results indicated that miRNA-524-5p inhibited angiogenesis in colon cancer cells via targeting WNK1.NEW & NOTEWORTHY MiRNA-524-5p inhibited angiogenesis in colon cancer cells via targeting with-no-lysine kinase 1.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Neovascularização Patológica/metabolismo , Proteína Quinase 1 Deficiente de Lisina WNK/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Neoplasias Experimentais , Regulação para Cima , Proteína Quinase 1 Deficiente de Lisina WNK/genética
6.
Ecol Evol ; 9(18): 10654-10664, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31624573

RESUMO

Changes in precipitation regimes and wind velocity tend to alter structure and composition of the annual herb plant community, with consequent effects on ecological functioning and biodiversity maintenance. We examined the effects of increased precipitation and reduced wind velocity on annual herb plant community characteristics via a manipulative experiment from the middle of April to middle of August, 2016. There was significant increment in species richness with increased precipitation from June to August, and there were interactive effects between increased precipitation and reduced wind velocity especially in June and the end of July. From June to August, increased precipitation, reduced wind velocity as well as their interaction stimulated sandy plant community development. There was considerable elevation in plant coverage with increased precipitation, and also there was an interactive effect of increased precipitation with 20% reduced wind velocity. However, reduced wind velocity caused more significant stimulation (p < .01) in plant height. Moreover, dominant plants, Salsola collina, Bassia dasyphylla, and Setaria viridis, contributed equally to the elevated community coverage with increased precipitation, whereas S. collina occupied a much larger proportion on the augment of community height compared with the other two species under the increased precipitation and reduced wind velocity. Elevated Shannon-Wiener index was detected with increased precipitation in June and July. Furthermore, increased precipitation and reduced wind velocity enhanced aboveground and belowground biomass, respectively. These species traits-in structuring and composing plant community were suggested to be conducive to deep understanding the plant functioning and dynamics under global changing precipitation regimes and atmospheric wind velocity scenarios.

7.
Am J Transl Res ; 9(12): 5461-5472, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312498

RESUMO

Long noncoding RNA (lncRNA) small ubiquitin-like modifier 1 pseudogene 3 (SUMO1P3) acts a tumor promoter in several malignancies; however, its roles in colon cancer remain unclear. Herein, we demonstrated that SUMO1P3 expression was significantly higher in colon cancer tissues and cell lines than the corresponding non-tumor samples and normal colonic epithelial cells, respectively. The upregulation of SUMO1P3 was positively correlated with the advanced histological stages, metastases, angiogenesis and poor prognosis of colon cancer patients. SUMO1P3 knockdown repressed the proliferation, migration, invasion, and pro-angiogenesis of colon cancer cells in vitro. SUMO1P3 silencing reduced the growth, liver metastasis, and vascularization of colon cancer in vivo. Mechanistically, SUMO1P3 depletion decreased the levels of cyclin D1, Vimentin, and VEGFA while increased E-cadherin expression in xenograft tumor tissues. Overall, these results indicate that SUMO1P3 expedites the malignant behaviors of colon cancer and may be as a potential therapeutic target.

8.
Oncol Rep ; 36(6): 3700-3706, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27748902

RESUMO

The present study aimed to investigate the proteomic difference between melanosis coli (MC) alone and melanosis coli with colon cancer (MCCC). Protein expression in patients with different diseases was analyzed using two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/TOF-MS). A total of 14 protein differences with a confidence level of >95% were found. There were six differences between MC and normal tissues, in which two proteins exhibited upregulated expression levels and four proteins exhibited downregulated expression levels in MC. Furthermore, one protein was expressed only in MC (P<0.05). In addition, there were differences in the expression of eight proteins between MC and MCCC tissues, in which one protein had an upregulated expression in MC tissues and seven proteins had an upregulated expression in MCCC tissues. Furthermore, two proteins were only expressed in MCCC tissues (P<0.05). Eight proteins were identified using mass spectrometry and database search. In conclusion, comparative proteomics accurately displayed the expression differences in eight proteins between MC, MCCC and normal colon tissues.


Assuntos
Colo/metabolismo , Neoplasias do Colo/metabolismo , Melanose/metabolismo , Proteoma/metabolismo , Biomarcadores Tumorais/metabolismo , Estudos de Casos e Controles , Colo/patologia , Eletroforese em Gel Bidimensional , Humanos , Proteômica
9.
Med Sci Monit ; 22: 2492-500, 2016 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-27421245

RESUMO

BACKGROUND This study was designed to improve our understanding of the role of miR-18a and its target (connective tissue growth factor (CTGF), which are mediators in HBX-induced hepatocellular carcinoma (HCC). MATERIAL AND METHODS We first investigated the expression of several candidate microRNAs (miRNAs) reported to have been aberrantly expressed between HepG2 and HepG2.2.15, which is characterized by stable HBV infection, while the CTGF is identified as a target of miR-18a. Furthermore, the expression of CTGF evaluated in HepG2 was transfected with HBX, while the HepG2.2.15 was transfected with miR-18a and CTGF siRNA. We examined the cell cycle at the same time. RESULTS We found that the expression of miR-18a was abnormally reduced in the HBV-positive HCC tissue samples compared with HBV-negative HCC samples. Through the use of a luciferase reporter system, we also identified CTGF 3'UTR (1046-1052 bp) as the exact binding site for miR-18a. We also observed a clear increase in CTGF mRNA and protein expression levels in HBV-positive HCC human tissue samples in comparison with the HBV-negative controls, indicating a possible negatively associated relationship between miR-18a and CTGF. Furthermore, we investigated the effect of HBX overexpression on miR-18a and CTGF, as well as the viability and cell cycle status of HepG2 cells. In addition, we found that HBX introduction downregulated miR-18a, upregulated CTGF, elevated the viability, and promoted cell cycle progression. We transfected HepG2.2.15 with miR-18a mimics and CTGF siRNA, finding that upregulated miR-18a and downregulated CTGF suppress the viability and cause cell cycle arrest. CONCLUSIONS Our study shows the role of the CTGF gene as a target of miR-18a, and identifies the function of HBV/HBX/miR-18a/CTGF as a key signaling pathway mediating HBV infection-induced HCC.


Assuntos
Carcinoma Hepatocelular/virologia , Fator de Crescimento do Tecido Conjuntivo/genética , Hepatite B Crônica/virologia , Neoplasias Hepáticas/virologia , MicroRNAs/genética , Transativadores/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Estudos de Casos e Controles , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Regulação para Baixo , Células Hep G2 , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/genética , Hepatite B Crônica/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais , Transativadores/metabolismo , Regulação para Cima , Proteínas Virais Reguladoras e Acessórias
10.
Pak J Pharm Sci ; 27(3 Suppl): 625-31, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24816694

RESUMO

Impact of Cr(3+) pollution on soil microbial quantity, enzyme activity and biological activity in purple paddy soil were studied under incubation conditions. The results showed that amounts of all tested microbes and enzyme activities in soil were inhibited by low Cr(3+) concentration (200mg/kg). After 7-day incubation, sulfate-reducing activity, methanogen activity, denitrifying activity and anaerobic nitrogen-fixing activity in soil were reduced by 34%, 66%, 98% and 65% respectively. Amounts of soil microbes were remarkably inhibited with medium Cr(3+) concentration (400mg/kg), all with reduction of more than 50%; and all tested soil biological activity was almost recovered in the fourth week except soil denitrifying activity. Activities of urease, invertase, neutral phosphatase and catalase were decreased by 60%, 21%, 59% and 42%, respectively. With high Cr(3+) concentration (1600mg/kg), amounts and activities of tested microbes had only about 1% of that with control. As calculated from the regression equation, the ED50 (ecological dose) values of activities of soil urease, invertase and catalase were around 800mg/kg; the ED50 values of soil sulfate-reducing activity, methanogen activity and anaerobic nitrogen-fixing activity were also around 800mg/kg with an exception of soil denitrifying activity which ranged 35 to 39 mg/kg. According to the Standards of National Soil Environmental Quality in China and their sensitivities to 400mg/kg Cr(3+) concentration, quantity of denitrifying bacteria, urease activity and denitrifying activity could be selected as indicators of early warning for Cr(3+) pollution in purple paddy soil.


Assuntos
Bactérias/efeitos dos fármacos , Cromo/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade
11.
Pak J Pharm Sci ; 27(3 Suppl): 643-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24816695

RESUMO

The study focused on the change of microbial characteristics affected by Plumbum pollution with purple paddy soil in an incubation experiment. The results showed that low concentration of Plumbum had little effect on most of microbial amounts, biological activity and enzymatic activity. However, denitrifying activity was inhibited severely, and inhibition rate was up to 98%. Medium and high concentration of Plumbum significantly reduced the amounts and activity of all microorganisms and enzymatic activity, which increased with incubation time. Negative correlations were found between Plumbum concentrations and microbial amounts, biological activity and enzymatic activities except fungi and actinomyces. Thus they can be used to indicate the Plumbum pollution levels to some extent. LD(50) of denitrifying bacteria (DB) and ED50 of denitrifying activity were 852mg/kg and 33.5mg/kg. Across all test soil microbes, denitrifying bacteria was most sensitive to Plumbum pollution in purple paddy soil. Value of early warning showed that anaerobic cellulose-decomposing bacteria (ACDB) and actinomyces were also sensitive to Plumbum pollution. We concluded that denitrifying activity, actinomyces, ACDB or DB can be chosen as predictor of Plumbum contamination in purple paddy soil.


Assuntos
Bactérias/efeitos dos fármacos , Chumbo/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade , Bactérias/metabolismo , Desnitrificação , Solo/química
12.
Chem Commun (Camb) ; 49(45): 5222-4, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23628851

RESUMO

It was found for the first time that single tail ionic liquid (IL) surfactants, 1-alkyl-3-methylimidazolium bromides [C(n)mim]Br (n = 10, 12, 14), form unilamellar vesicles in aqueous solutions without any additives. With the increase in IL concentrations, the self-assembly of these ILs can transfer from spherical micelles to rodlike micelles and then to vesicles.

13.
J Phys Chem B ; 115(17): 4955-62, 2011 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-21480622

RESUMO

Material preparation in ionic liquids and environmental pollution control by ionic liquids are often closely dependent on the aggregation behavior of ionic liquids in solution. In the present work, conductivity, fluorescence probe, and dynamic light scattering techniques have been used to study the effect of organic solvents on the aggregation behavior of 1-dodecyl-3-methylimidazolium bromide in water. It was shown that the critical aggregation concentration (CAC), the ionization degree of the aggregates (α), and the standard Gibbs energy of aggregation (ΔG(m)°) of the ionic liquid increase, while its aggregation number (N(agg)) and aggregates' size decrease with increasing concentration of organic additives in water. These results have been discussed from the favorable interactions of alkyl chain of the ionic liquid with the mixed solvents. It is suggested that the solvophobic parameter, characterized quantitatively by Gibbs energy of transfer of hydrocarbon from gas into a given solvent, can be used to account for the effect of organic additives on the formation and growth of the ionic liquid aggregates in water. Aggregation behavior of ionic liquids in aqueous organic solutions can be modulated simply by the solvophobic parameters of hydrocarbon in the mixed solvents.


Assuntos
Brometos/química , Imidazóis/química , 1-Propanol/química , Acetona/química , Acetonitrilas/química , Dimetil Sulfóxido/química , Etanol/química , Etilenoglicol/química , Etilenoglicóis/química , Formamidas/química , Líquidos Iônicos/química , Metanol/química , Polietilenoglicóis/química , Soluções , Solventes/química , Termodinâmica , Água/química
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