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1.
Acta Pharmacol Sin ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698214

RESUMO

The retinoic acid receptor-related orphan receptor γ (RORγ) is regarded as an attractive therapeutic target for the treatment of prostate cancer. Herein, we report the identification, optimization, and evaluation of 1,2,3,4-tetrahydroquinoline derivatives as novel RORγ inverse agonists, starting from high throughput screening using a thermal stability shift assay (TSA). The representative compounds 13e (designated as XY039) and 14a (designated as XY077) effectively inhibited the RORγ transcriptional activity and exhibited excellent selectivity against other nuclear receptor subtypes. The structural basis for their inhibitory potency was elucidated through the crystallographic study of RORγ LBD complex with 13e. Both 13e and 14a demonstrated reasonable antiproliferative activity, potently inhibited colony formation and the expression of AR, AR regulated genes, and other oncogene in AR positive prostate cancer cell lines. Moreover, 13e and 14a effectively suppressed tumor growth in a 22Rv1 xenograft tumor model in mice. This work provides new and valuable lead compounds for further development of drugs against prostate cancer.

2.
Acta Pharmacol Sin ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632319

RESUMO

Liver receptor homolog-1 (LRH-1), a member of the nuclear receptor superfamily, is a ligand-regulated transcription factor that plays crucial roles in metabolism, development, and immunity. Despite being classified as an 'orphan' receptor due to the ongoing debate surrounding its endogenous ligands, recent researches have demonstrated that LRH-1 can be modulated by various synthetic ligands. This highlights the potential of LRH-1 as an attractive drug target for the treatment of inflammation, metabolic disorders, and cancer. In this review, we provide an overview of the structural basis, functional activities, associated diseases, and advancements in therapeutic ligand research targeting LRH-1.

3.
Oral Dis ; 29(1): 105-115, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33872442

RESUMO

Recently, lncRNAs are associated with the progression and development of various cancers. We aimed to explore the effects of lncRNA SNHG1 on the proliferation, apoptosis, migration, and invasion of oral squamous cell carcinoma (OSCC) cells. Quantitative real-time PCR (RT-qPCR) was used for measurement of SNHG1 in OSCC cells. Cell proliferation, apoptosis, migration, and invasion were detected by CCK-8 assay, flow cytometry, Cell Death Detection ELISA PLUS kit, and transwell assays. Dual-luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay were used to clarify the relationship between SNHG1 and miR-186. SNHG1 was overexpressed in OSCC cells. SNHG1 silencing prevented cell proliferation and increased the incidence of apoptosis, DNA fragments, cleaved-caspase 3, and Bax protein levels. Cell migration and invasion were reduced after SNHG1 deletion, and MMP2 and MMP9 protein levels were decreased. SNHG1 overexpression promoted cell survival, migration, and invasion, reduced DNA fragments formation. Mechanistically, we demonstrated that SNHG1 could directly bind to miR-186 and positively regulated α1, 6-fucosyltransferase (FUT8) level. Functional investigation showed that miR-186 depletion reversed the roles of SNHG1 silencing in cell proliferation, apoptosis, and migration. Taken together, our findings illuminated that SNHG1 regulated cell proliferation, migration, and invasion by sponging miR-186 to depress FUT8 expression.


Assuntos
Fucosiltransferases , MicroRNAs , Neoplasias Bucais , RNA Longo não Codificante , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Fucosiltransferases/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Bucais/genética , RNA Longo não Codificante/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
4.
iScience ; 25(12): 105483, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36387024

RESUMO

The conjugative pilus expression (Cpx) stress response system can sense cell envelope stressors, such as misfolded proteins, and upregulate proteases to modify or degrade damaged proteins. YihE is a protein kinase implicated in the Cpx system, and Rho is a transcription termination factor in prokaryotes, but no functional connection between YihE and Rho has been reported. Here, we found that YihE can interact with Rho to form a binary complex with a stoichiometric ratio of 6:1 (Rho:YihE). A low resolution of Rho crystal structure in the presence of YihE was determined. YihE overexpression helped lessen the aberrant effects caused by Rho overexpression, including long cell morphology and other Rho-mediated phenotypes. Overall, YihE is a Rho binding partner that acts as a Rho antagonist in the Cpx stress. YihE binding to Rho would compete RNA from binding to Rho, thereby helping bacteria cope with stress through the regulation of Rho-dependent transcription termination.

5.
Front Cell Dev Biol ; 10: 902403, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092721

RESUMO

Homologous recombination (HR) is an error-free DNA double-strand break (DSB) repair pathway, which safeguards genome integrity and cell viability. Human C-terminal binding protein (CtBP)-interacting protein (CtIP) is a central regulator of the pathway which initiates the DNA end resection in HR. Ubiquitination modification of CtIP is known in some cases to control DNA resection and promote HR. However, it remains unclear how cells restrain CtIP activity in unstressed cells. We show that the ubiquitin E3 ligase PPIL2 is recruited to DNA damage sites through interactions with an HR-related protein ZNF830, implying PPIL2's involvement in DNA repair. We found that PPIL2 interacts with and ubiquitinates CtIP at the K426 site, representing a hereunto unknown ubiquitination site. Ubiquitination of CtIP by PPIL2 suppresses HR and DNA resection. This inhibition of PPIL2 is also modulated by phosphorylation at multiple sites by PLK1, which reduces PPIL2 ubiquitination of CtIP. Our findings reveal new regulatory complexity in CtIP ubiquitination in DSB repair. We propose that the PPIL2-dependent CtIP ubiquitination prevents CtIP from interacting with DNA, thereby inhibiting HR.

6.
Int J Mol Sci ; 23(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35163484

RESUMO

Bacterial cryptic prophage (defective prophage) genes are known to drastically influence host physiology, such as causing cell growth arrest or lysis, upon expression. Many phages encode lytic proteins to destroy the cell envelope. As natural antibiotics, only a few lysis target proteins were identified. ydfD is a lytic gene from the Qin cryptic prophage that encodes a 63-amino-acid protein, the ectopic expression of which in Escherichia coli can cause nearly complete cell lysis rapidly. The bacterial 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway is responsible for synthesizing the isoprenoids uniquely required for sustaining bacterial growth. In this study, we provide evidence that YdfD can interact with IspG, a key enzyme involved in the MEP pathway, both in vivo and in vitro. We show that intact YdfD is required for the interaction with IspG to perform its lysis function and that the mRNA levels of ydfD increase significantly under certain stress conditions. Crucially, the cell lysis induced by YdfD can be abolished by the overexpression of ispG or the complementation of the IspG enzyme catalysis product methylerythritol 2,4-cyclodiphosphate. We propose that YdfD from the Qin cryptic prophage inhibits IspG to block the MEP pathway, leading to a compromised cell membrane and cell wall biosynthesis and eventual cell lysis.


Assuntos
Biocatálise , Eritritol/análogos & derivados , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Prófagos/metabolismo , Fosfatos Açúcares/metabolismo , Proteínas Virais/metabolismo , Sequência Conservada , Cisteína/química , Eritritol/metabolismo , Escherichia coli/ultraestrutura , Modelos Biológicos , Ligação Proteica , Estrutura Secundária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Soluções , Estresse Fisiológico , Proteínas Virais/química
7.
FEBS J ; 287(16): 3579-3599, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31967710

RESUMO

Aspartate transcarbamoylase (ATCase) is a key enzyme which regulates and catalyzes the second step of de novo pyrimidine synthesis in all organisms. Escherichia coli ATCase is a prototypic enzyme regulated by both product feedback and substrate cooperativity, whereas human ATCase is a potential anticancer target. Through structural and biochemical analyses, we revealed that R167/130's loop region in ATCase serves as a gatekeeper for the active site, playing a new and unappreciated regulatory role in the catalytic cycle of ATCase. Based on virtual compound screening simultaneously targeting the new regulatory region and active site of human ATCase, two compounds were identified to exhibit strong inhibition of ATCase activity, proliferation of multiple cancer cell lines, and growth of xenograft tumors. Our work has not only revealed a previously unknown regulatory region of ATCase that helps uncover the catalytic and regulatory mechanism of ATCase, but also successfully guided the identification of new ATCase inhibitors for anticancer drug development using a dual-targeting strategy. DATABASE: Structure data are available in Protein Data Bank under the accession numbers: 6KJ7 (G166P ecATCase), 6KJ8 (G166P ecATCase-holo), 6KJ9 (G128/130A ecATCase), and 6KJA (G128/130A ecATCase-holo).


Assuntos
Aspartato Carbamoiltransferase/antagonistas & inibidores , Domínio Catalítico , Inibidores Enzimáticos/farmacologia , Simulação de Dinâmica Molecular , Regulação Alostérica , Sequência de Aminoácidos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Aspartato Carbamoiltransferase/química , Aspartato Carbamoiltransferase/metabolismo , Biocatálise/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Inibidores Enzimáticos/química , Feminino , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Homologia de Sequência de Aminoácidos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
8.
J Asian Nat Prod Res ; 22(11): 1065-1077, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762317

RESUMO

Many kinds of drugs induce pseudo-allergic reactions due to activation of mast cells. We investigated the anti-pseudo-allergic effect of andrographolide (Andro). The effects of Andro on pseudo-allergic reactions were investigated in vivo and in vitro. Andro suppressed compound 48/80 (C48/80) induced pseudo-allergic reactions in mice in a dose-dependent manner. Andro also inhibited C48/80-induced local inflammatory reactions in mice. In vitro studies revealed that Andro reduced C48/80-induced mast cells degranulation. Human phospho-kinase array kit and western blotting showed that Andro could inhibit pseudo-allergic responses via the calcium signaling pathway.


Assuntos
Diterpenos , Hipersensibilidade , Animais , Diterpenos/farmacologia , Humanos , Mastócitos , Camundongos , Estrutura Molecular , Secretagogos
9.
J Sep Sci ; 42(12): 2171-2178, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30950563

RESUMO

Lanosterol is a potential drug for cataracts treatment, which can reverse the aggregation of intracrystalline proteins. The low concentration in lanolin calls for high-performance separation methods. In this study, a counter-current chromatography dual-mode elution method was developed for the first time to separate and purify lanosterol from hexane extract of lanolin after saponification, in which the column was first eluted with the lower phase as mobile phase in head-to-tail mode, followed by the upper phase in the tail-to-head mode. High purity of lanosterol, dihydrolanosterol, and cholesterol can be obtained simultaneously. A solvent system composed of n-heptane/acetonitrile/ethyl acetate (5:5:1, v/v/v) was selected and optimized via partition coefficient determination. Compounds such as 111 mg lanosterol, 84 mg dihydrolanosterol, and 183 mg cholesterol with high purity of 99.77, 95.71, and 91.43%, respectively, analyzed by high-performance liquid chromatography were obtained within 80 min from 700 mg crude extract from 1.78 g lanolin. The method was also used to improve the purity of commercial lanosterol product from 66.97 to above 99%. Counter-current chromatography could serve as a potential and powerful technique for commercial production of highly pure lanosterol.


Assuntos
Colesterol/isolamento & purificação , Lanolina/química , Lanosterol/isolamento & purificação , Colesterol/química , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Lanosterol/química , Conformação Molecular
10.
RSC Adv ; 9(9): 5002-5008, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35514670

RESUMO

Star anise essential oil (SAEO) has a variety of antioxygenic and antimicrobial properties, and is widely used in food preservation. However, its application is still challenging due to poor water solubility and physicochemical stability. We now report that encapsulation of SAEO in hydroxypropyl-ß-cyclodextrin (HPCD) enhances its water solubility, as well as its thermal, storage, and photostability. The solubility of SAEO encapsulated by HPCD was increased by 47.5 times at 45 °C, and the onset temperature of thermal volatilization was delayed by at least 200 °C. The encapsulated material is also more uniformly and more stably dispersed in xanthan gum, and is thus released in a controlled manner. Importantly, fresh-cut Chinese yam coated with xanthan gum containing encapsulated SAEO is more effectively preserved, as assessed using weight loss, L* value, browning index, and polyphenol oxidase activity. The data suggest that the encapsulated SAEO reduced the weight loss of the samples by more than 30%, and the encapsulation of HPCD increased the inhibitory effect of SAEO on browning and polyphenol oxidase activity of the samples by nearly 8 times and more than 7 times, respectively. Collectively, SAEO encapsulated in HPCD is promising as a preservative coat for fresh-cut fruits and vegetables.

11.
J Clin Lab Anal ; 32(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28464393

RESUMO

BACKGROUND: Apurinic/apyrimidinic endonuclease 1 (APEX1) plays a central role in the repair of oxidative DNA lesions via base excision repair, and polymorphism in the APEX1 gene may affect susceptibility to carcinogenesis. METHODS: Here, we assessed possible relationships between single-nucleotide polymorphism at APEX1 rs1760944 and risk of nasopharyngeal carcinoma (NPC) in 477 NPC patients and 558 healthy controls from Guangxi province, which is the second largest NPC endemic area in South China. RESULTS: Genotype frequencies in controls were in Hardy-Weinberg equilibrium. Logistic regression analysis identified the genotypes GT or GG as associated with significantly lower risk than the genotype TT (adjusted odds ratio [OR] 0.745, 95% confidence interval [CI] 0.573-0.970). This apparent protective effect of GT/GG was even greater among those with no smoking history (adjusted OR 0.679, 95%CI 0.494-0.934). CONCLUSION: Our results suggest that APEX1 rs1760944 polymorphism may correlate with NPC susceptibility in a population from an endemic area in South China.


Assuntos
Carcinoma/epidemiologia , Carcinoma/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Predisposição Genética para Doença/genética , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo
12.
Dis Markers ; 2017: 6309754, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28694559

RESUMO

The aim of this study was to explore potential relationships of four single-nucleotide polymorphisms (SNPs) in the gene encoding dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) with risk of nasopharyngeal carcinoma (NPC). The DC-SIGN SNPs rs7252229, rs4804803, rs2287886, and rs735240 were genotyped in 477 unrelated NPC patients and 561 cancer-free controls. At rs7252229, risk of NPC was significantly lower in individuals with GC (odds ratio [OR] 0.076, 95% confidence interval [CI] 0.008-0.690), GG (OR 0.056, 95%CI 0.006-0.487), or GC + GG (OR 0.059, 95%CI 0.007-0.515) than in individuals with the CC genotype, after adjusting for age, gender, smoking history, and EBV-VCA-IgA status. At rs4804803, risk of NPC was significantly higher in individuals with the genotype GG than in those with the genotype AA (adjusted OR 9.038, 95%CI 1.708-47.822). At rs735240, risk of NPC did not change significantly with genotypes AG, GG, or AG + GG after adjusting for age, gender, and smoking history. However, when data were also adjusted for EBV-VCA-IgA status, three genotypes emerged as associated with significantly higher risk of NPC than the AA genotype: AG (OR 2.976, 95%CI 1.123-7.888), GG (OR 3.314, 95%CI 1.274-8.622), or GG + AG (OR 3.191, 95%CI 1.237-8.230). Our results suggest that DC-SIGN SNPs rs7252229, rs4804803, and rs735240 may influence NPC risk in the Chinese population. The mechanisms mediating this risk require a further study.


Assuntos
Carcinoma/diagnóstico , Carcinoma/genética , Moléculas de Adesão Celular/genética , Predisposição Genética para Doença , Lectinas Tipo C/genética , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/genética , Adulto , Alelos , Povo Asiático , Carcinoma/etnologia , Carcinoma/patologia , Estudos de Casos e Controles , Feminino , Expressão Gênica , Frequência do Gene , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/etnologia , Neoplasias Nasofaríngeas/patologia , Regiões Promotoras Genéticas , Risco , Fumar
13.
Quant Imaging Med Surg ; 6(3): 334-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27429922
14.
Interdiscip Sci ; 8(3): 319-26, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27165480

RESUMO

Chromogranin A (CGA)-N46, a derived peptide of human chromogranin A, has antifungal activity. To further research the active domain of CGA-N46, a series of derivatives were designed by successively deleting amino acid from both terminus of CGA-N46, and the amino acid sequence of each derivative was analyzed by bioinformatic software. Based on the predicted physicochemical properties of the peptides, including half-life time in mammalian reticulocytes (in vitro), yeast (in vivo) and E. coli (in vivo), instability index, aliphatic index and grand average of hydropathicity (GRAVY), the secondary structure, net charge, the distribution of hydrophobic residues and hydrophilic residues, the final derivatives CGA-N15, CGA-N16, CGA-N12 and CGA-N8 were synthesized by solid-phase peptide synthesis. The results of bioinformatic analysis showed that CGA-N46 and its derivatives were α-helix, neutral or weak positive charge, hydrophilic, and CGA-N12 and CGA-N8 were more stable than the other derivatives. The results of circular dichroism confirmed that CGA-N46 and its derived peptides displayed α-helical structure in an aqueous solution and 30 mM sodium dodecylsulfate, but α-helical contents decreased in hydrophobic lipid vesicles. CGA-N15, CGA-N16, CGA-N12 and CGA-N8 had higher antifungal activities than their mother peptide CGA-N46. Among of the derived peptides, CGA-N12 showed the least hemolytic activity. In conclusion, we have successfully identified the active domain of CGA-N46 with strong antifungal activity and weak hemolytic activity, which provides the possibility to develop a new class of antibiotics.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Cromogranina A/química , Dicroísmo Circular , Hemólise/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Peptídeos/efeitos adversos , Relação Estrutura-Atividade
15.
PLoS One ; 11(1): e0146215, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26751791

RESUMO

UNLABELLED: Gastrointestinal motility may be impaired after intestinal surgery. Epidural morphine is effective in controlling postoperative pain, but can further reduce gastrointestinal motility. Here, we aimed to investigate the effects of epidural dexmedetomidine on gastrointestinal motility in patients undergoing colonic resection. Seventy-four patients undergoing colonic resection were enrolled in this clinical trial and allocated randomly to treatment with dexmedetomidine (D group) or morphine (M group). The D group received a loading dose epidural administration of 3 ml dexmedetomidine (0.5 µg kg(-1)) and then a continuous epidural administration of 80 µg dexmedetomidine in 150 ml levobupivacaine (0.125%) at 3 ml h(-1) for two days. The M group received a loading dose epidural administration of 3 ml morphine (0.03 mg kg(-1)) and then a continuous epidural administration of 4.5 mg morphine in 150 ml levobupivacaine at 3 ml h(-1) for two days. Verbal rating score (VRS), postoperative analgesic requirements, side effects related to analgesia, the time to postoperative first flatus (FFL) and first feces (FFE) were recorded. VRS and postoperative analgesic requirements were not significantly different between treatment groups. In contrast, the time to FFL and time to FFE were significant longer in M group in comparison to D group (P < 0.05). Moreover, patients in M group had a significantly higher incidence of nausea, vomiting, and pruritus (P < 0.05). No patients showed neurologic deficits in either group. In comparison to morphine, epidural dexmedetomidine is safe and beneficial for the recovery of gastrointestinal motility after colonic resection when used as an adjunct with levobupivacaine for postoperative pain control. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR-TRC-14004644.


Assuntos
Analgesia Epidural/métodos , Bupivacaína/análogos & derivados , Colo/cirurgia , Dexmedetomidina/administração & dosagem , Motilidade Gastrointestinal/efeitos dos fármacos , Morfina/administração & dosagem , Idoso , Bupivacaína/administração & dosagem , Colo/efeitos dos fármacos , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada/métodos , Fezes , Feminino , Flatulência , Humanos , Levobupivacaína , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Dor Pós-Operatória/terapia , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
16.
Interdiscip Sci ; 8(3): 277-83, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26341498

RESUMO

CGA-N46 is a small antifungal-derived peptide and consists of the 31st-76th amino acids of the N-terminus of human chromogranin A. Polycistronic expression of recombinant CGA-N46 in Bacillus subtilis DB1342 was used to improve its production, but the yield of CGA-N46 was still low. In the present study, response surface methodology (RSM) was used to optimize culture medium composition and growth conditions of the engineered strain B. subtilis DB1342(p-3N46) for the further increase in CGA-N46 yield. The results of two-level factorial experiments indicated that dextrin and tryptone were significant factors affecting CGA-N46 expression. Central composite design (CCD) was used to determine the ideal conditions of each significant factors. From the results of CCD, the optimal medium composition was predicted to be dextrin 16.6 g/L, tryptone 19.2 g/L, KH2PO4·H2O 6 g/L, pH 6.5. And the optimal culture process indicated inoculation of B. subtilis DB1342(p-3N46) seed culture into fresh culture medium at 5 % (v/v), followed by expression of CGA-N46 for 56 hours at 30 °C induced by 2 % (v/v) sucrose after one hour of shaking culture. To test optimal CGA-N46 peptide expression, the yeast growth inhibition assay was employed and it was found that under optimal culture conditions, CGA-N46 inhibited the growth of Candida albican by 42.17, 30.86 % more than that in the pre-optimization conditions. In summary, RSM can be used to optimize expression conditions of CGA-N46 in engineered strains B. subtilis DB1342(p-3N46).


Assuntos
Antifúngicos/metabolismo , Antifúngicos/farmacologia , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/farmacologia , Bioengenharia/métodos , Bioestatística/métodos , Meios de Cultura , Leveduras/efeitos dos fármacos
17.
Exp Ther Med ; 10(6): 2289-2294, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26668630

RESUMO

CGA-N46 is a novel antifungal peptide derived from the N-terminus of human Chromogranin A, corresponding to the 31st to 76th amino acids. Further research on its activities and characteristics may be helpful for the application of CGA-N46 in medical or other situations. In the present study, the antifungal spectrum and physicochemical characteristics of CGA-N46 were investigated using an antifungal assay, its antiproliferative effects on cancer and normal cells were assessed using MTT assay and its combinatorial effect with other antibiotics was analyzed using checkerboard analysis. The results showed that CGA-N46 exhibited antifungal activity against the tested Candidas (C. glabrata, C. parapsilosis, C. krusei, C. tropicalis and C. albicans) at a concentration of <0.8 mM, but had no effect on the growth of filamentous fungi or other types of fungi (Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Fusarium moniliforme, Microsporum canis, Microsporum gypseum, Trichophyton rubrum and Trichophyton mentagrophytes), even at a concentration of 3.2 mM. CGA-N46 had an inhibitory effect on the proliferation of lung cancer A549 cells and a reversible effect on the growth of normal primary chicken embryo fibroblast cells, but no hemolytic activity on human erythrocytes at the minimum inhibitory concentration of CGA-N46 against yeasts. The antifungal activity of CGA-N46 was stable at a temperature <40°C or within a broad pH range (pH 5.0-7.0). Its antifungal activity was enhanced when the peptide was used in combination with fluconazole and terbinafine. The present results indicate that CGA-N46 is a safe, physicochemically stable, antifungal peptide with anticancer cell activity that exhibits an additive effect with conventional antibiotics.

18.
Exp Ther Med ; 10(5): 1768-1776, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26640548

RESUMO

Candida species (Candida spp.) are important fungal pathogens, which cause numerous clinical diseases associated with significant mortality and morbidity in healthcare settings. In our previous study, we identified a recombinant peptide, chromogranin A (CGA)-N46, corresponding to the N-terminal Pro31-Gln76 sequence of human CGA, that exhibited antifungal activity against Candida albicans. The present study investigated the antifungal activity of CGA-N46, and its underlying mechanism, against numerous Candida spp. CGA-N46 inhibited the growth of all of the tested Candida spp., of which Candida krusei exhibited the greatest sensitivity. CGA-N46 was able to disrupt the stability of the phospholipid monolayer without damaging the integrity and permeability of the outer membrane of C. krusei cells, and induced cytoplasm vacuolization and mitochondrial damage. In addition, treatment of C. krusei with CGA-N46 was associated with decreased levels of intracellular reactive oxygen species, a reduction in the mitochondrial membrane potential, and DNA synthesis inhibition. The results of the present study suggested that CGA-N46 was able to pass through the cell membrane of Candida spp. by temporarily destabilizing the phospholipid membrane, which in turn led to mitochondrial dysfunction and inhibition of DNA synthesis. Therefore, CGA-N46 may be considered a novel antifungal compound for the treatment of patients with C. krusei infections.

19.
Interdiscip Sci ; 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25682381

RESUMO

CGA-N46 is a small antifungal derived peptide and consists of the 31st to 76th amino acids of the N-terminus of human chromogranin A. Polycistronic expression of recombinant CGA-N46 in Bacillus subtilis DB1342 was used to improve its production, but the yield of CGA-N46 was still low. In the present study, response surface methodology (RSM) was used to optimize culture medium composition and growth conditions of the engineered strain B. subtilis DB1342(p-3N46) for the further increase of CGA-N46 yield. The results of two-level factorial experiments indicated that dextrin and tryptone were significant factors affecting CGA-N46 expression. Central composite design (CCD) was used to determine the ideal conditions of each significant factors. From the results of CCD, the optimal medium composition was predicted to be dextrin 16.6 g/L, tryptone 19.2 g/L, KH2PO4·3H2O 6 g/L, pH 6.5. And the optimal culture process was indicated that B. subtilis DB1342(p-3N46) seed culture was inoculated into fresh culture medium at 5% (v/v), followed by expression of CGA-N46 for 56 hours at 30°C induced by 2% (v/v) sucrose after one hour of shaking culture. To test optimal CGA-N46 peptide expression, the yeast growth inhibition assay was employed and it was found that under optimal culture conditions, CGA-N46 inhibited the growth of C. albican by 42.17%, 30.86% more than that in the pre-optimization conditions. In summary, RSM can be used to optimize expression conditions of CGA-N46 in engineered strains B. subtilis DB1342(p-3N46).

20.
Biomed Mater ; 10(1): 015002, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25534880

RESUMO

A microcapsule prepared from triblock copolymer poly(lactic acid)-poly(ethylene glycol)-poly(lactic acid) (PLA-PEG-PLA, PELA) was investigated as a controlled release carrier for recombinant human bone morphogenetic protein-2 (rhBMP-2). The rhBMP-2/PELA microspheres were prepared using the water-in-oil-in-water (W/O/W) solvent evaporation method. This work was conducted to optimize the entrapping conditions of the rhBMP-2 loaded PELA copolymer. The effects on encapsulation efficiency (EE) of different molecular weights (MW) of PEG in the copolymer, the amount of PELA, the amount of rhBMP-2, the span-20 concentration, the polyvinyl alcohol (PVA) concentration and stirring time were tested. On the basis of single-factor experiments, the optimum parameters were achieved using response surface methodology (RSM). The results showed that the highest EE of BMP-2 was achieved with a span-20 concentration of 0.5%, PEG MW 4000 Da, a stirring time of 30 min at 800 rpm min(-1), 282.3 mg of PELA, 1 µg of rhBMP-2 and PVA concentration 0.79%. Under these optimal conditions, it was predicted that the highest EE to be achieved would be 76.5%; the actual EE achieved was 75%.


Assuntos
Materiais Biocompatíveis/química , Proteína Morfogenética Óssea 2/química , Portadores de Fármacos , Poliésteres/química , Polietilenoglicóis/química , Fator de Crescimento Transformador beta/química , Emulsões , Humanos , Microesferas , Peso Molecular , Álcool de Polivinil/química , Proteínas Recombinantes/química , Solventes/química , Propriedades de Superfície
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