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1.
Int J Mol Sci ; 23(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36012706

RESUMO

Colorectal cancer therapies have produced promising clinical responses, but tumor cells rapidly develop resistance to these drugs. It has been previously shown that EC19 and EC23, two EC-synthetic retinoids, have single-agent preclinical anticancer activity in colorectal carcinoma. Here, isobologram analysis revealed that they have synergistic cytotoxicity with retinoic acid receptor (RAR) isoform-selective agonistic retinoids such as AC261066 (RARß2-selective agonist) and CD437 (RARγ-selective agonist) in Caco-2 cells. This synergism was confirmed by calculating the combination index (lower than 1) and the dose reduction index (higher than 1). Flow cytometry of combinatorial IC50 (the concentration causing 50% cell death) confirmed the cell cycle arrest at the SubG0-G1 phase with potentiated apoptotic and necrotic effects. The reported synergistic anticancer activity can be attributed to their ability to reduce the expression of ATP-binding cassette (ABC) transporters including P-glycoprotein (P-gp1), breast cancer resistance protein (BCRP) and multi-drug resistance-associated protein-1 (MRP1) and Heat Shock Protein 70 (Hsp70). This adds up to the apoptosis-promoting activity of EC19 and EC23, as shown by the increased Caspase-3/7 activities and DNA fragmentation leading to DNA double-strand breaks. This study sheds the light on the possible use of EC-synthetic retinoids in the rescue of multi-drug resistance in colorectal cancer using Caco-2 as a model and suggests new promising combinations between different synthetic retinoids. The current in vitro results pave the way for future studies on these compounds as possible cures for colorectal carcinoma.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Antineoplásicos/farmacologia , Apoptose , Células CACO-2 , Neoplasias Colorretais/tratamento farmacológico , Humanos , Proteínas de Neoplasias , Retinoides/farmacologia , Tretinoína/farmacologia
2.
J Chemother ; 34(6): 381-390, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34895107

RESUMO

High dose methotrexate (HDMTX) is an essential agent in chemotherapeutic regimens used in various hematological malignancies in Egyptian adults. The research for the impact of gene polymorphism on HDMTX induced toxicities and delayed elimination is an important ongoing objective in many studies, variable and conflicting results produced in the past years to clarify that impact. This study aimed to investigate the role of ABCB1 3435 C > T rs1045642 and MTHFR 677 C > T rs1801133 polymorphisms on HDMTX induced toxicity outcomes and delayed elimination in Egyptian adult patients with hematological malignancies. A prospective, observational cohort study was conducted on a total of 62 Egyptian adult patients with hematological malignancies age ≥ 18-years-old. All demographic, medical, and laboratory data were continuously collected from the patients' medical files in an up-to-date follow-up in selected clinics during the period from April 2018 to March 2020. Venous blood samples were collected for the purpose of genotyping, DNA extraction, and measurement of MTX levels. All the relevant data were statistically analyzed. The studied patients' median age was 25 years old with a range of (18-62) years. Forty-six patients were males with about 74%, and 16 were females with about 26%. Eighty-nine percent of the patients diagnosed with acute lymphoblastic leukemia 'ALL', 5% of the patients had B cell non-hodgkin lymphoma 'B-NHL' and 3% diagnosed with primary central nervous system lymphoma 'PCNSL' and Burkitt's lymphoma 'BL' Hematological, hepatic, renal and gastrointestinal toxicities observed post-HDMTX were recorded with the hematological toxicities toping on all the others, also patients with delayed elimination at 72 hours post the HDMTX dose were determined. Statistical analysis revealed a significant association between ABCB1 3435 C > T rs1045642 and HDMTX delayed elimination with about 10 times higher risk among the minor allele 'T' carriers (p-value = 0.006) (odds ratio [OR]: 10.470; 95% CI: 1.961-55.904). No significant association observed between the studied gene polymorphisms: MTHFR 677 C > T rs1801133, ABCB1 3435 C > T rs1045642, and different toxicity outcomes. According to our best knowledge, this study is the first to conclude a significant association between ABCB1 3435 C > T rs1045642 gene polymorphism and HDMTX delayed elimination at 72 hours post HDMTX infusion; also, it is the first study to analyze the association between ABCB1 3435 C > T rs1045642 polymorphism with HDMTX toxicity and delayed elimination in adult Egyptian patients with hematological malignancies.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP , Neoplasias Hematológicas , Metotrexato , Metilenotetra-Hidrofolato Redutase (NADPH2) , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adolescente , Adulto , Egito , Feminino , Neoplasias Hematológicas/induzido quimicamente , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/genética , Humanos , Masculino , Metotrexato/efeitos adversos , Metotrexato/farmacocinética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Polimorfismo Genético , Estudos Prospectivos , Adulto Jovem
3.
ACS Omega ; 6(46): 31282-31291, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34841172

RESUMO

Cyclocreatine and its water-soluble derivative, cyclocreatine phosphate (CCrP), are potent cardioprotective drugs. Based on recent animal studies, CCrP, FDA-awarded Orphan Drug Designation, has a promising role in increasing the success rate of patients undergoing heart transplantation surgery by preserving donor hearts during transportation and improving the recovery of transplanted hearts in recipient patients. In addition, CCrP is under investigation as a promising treatment for creatine transporter deficiency, an X-linked inborn error resulting in a poor quality of life for both the patients and the caregiver. A newly designed molecularly imprinted polymer (MIP) material was fabricated by the anodic electropolymerization of o-phenylenediamine on screen-printed carbon electrodes and was successfully applied as an impedimetric sensor for CCrP determination to dramatically reduce the analysis time during both the clinical trial phases and drug development process. To enhance the overall performance of the proposed sensor, studies were performed to optimize the electropolymerization conditions, incubation time, and pH of the background electrolyte. Scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry were used to characterize the behavior of the developed ultrathin MIP membrane. The CCrP-imprinted polymer has a high recognition affinity for the template molecule because of the formation of 3D complementary cavities within the polymer. The developed MIP impedimetric sensor had good linearity, repeatability, reproducibility, and stability within the linear concentration range of 1 × 10-9 to 1 × 10-7 mol/L, with a low limit of detection down to 2.47 × 10-10 mol/L. To verify the applicability of the proposed sensor, it was used to quantify CCrP in spiked plasma samples.

4.
Public Health Res Pract ; 31(4)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34753164

RESUMO

OBJECTIVES: To provide an overview of the current state of funding for health policy and systems research (HPSR) on a national level across the Eastern Mediterranean region (EMR), and to examine the key factors influencing funding for HPSR in the region. METHODS: A multistep approach was employed, involving a documentation review, secondary data analysis and key informant interviews with 30 stakeholders from five countries in the EMR. Findings are presented narratively (and where applicable as percentages). RESULTS: National funding for research and development (R&D) in general, and for health research in particular, has been low in comparative terms and lagging behind at the global scale, while funding for HPSR has been lacking on a national level. None of the 22 EMR countries studied had explicit national funding or a budget line for HPSR. Analysis of funding sources of 1821 published HPSR articles in the EMR (2010-2019) showed that the most notable source was external/international grants (45.6%), followed by university/academia (35.1%), and government (9.5%). Although HPSR publications have been increasing over time, this still falls short of the scale needed for strengthening health systems and informing current transformations in the region. Findings from the interviews identified several factors influencing investment in or funding for HPSR in the EMR. CONCLUSIONS: Many of the EMR's policy priorities are related to health systems, however our research finds that overall investment in health research and HPSR is still low, with limited recognition of the importance of HPSR in the EMR.


Assuntos
Política de Saúde , Pesquisa sobre Serviços de Saúde , Programas Governamentais , Humanos , Região do Mediterrâneo
5.
Front Immunol ; 12: 705581, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34426734

RESUMO

Autophagy is a proposed route of amyloid-ß (Aß) clearance by microglia that is halted in Alzheimer's Disease (AD), though mechanisms underlying this dysfunction remain elusive. Here, primary microglia from adult AD (5xFAD) mice were utilized to demonstrate that 5xFAD microglia fail to degrade Aß and express low levels of autophagy cargo receptor NBR1. In 5xFAD mouse brains, we show for the first time that AD microglia express elevated levels of microRNA cluster Mirc1/Mir17-92a, which is known to downregulate autophagy proteins. By in situ hybridization in post-mortem AD human tissue sections, we observed that the Mirc1/Mir17-92a cluster member miR-17 is also elevated in human AD microglia, specifically in the vicinity of Aß deposits, compared to non-disease controls. We show that NBR1 expression is negatively correlated with expression of miR-17 in human AD microglia via immunohistopathologic staining in human AD brain tissue sections. We demonstrate in healthy microglia that autophagy cargo receptor NBR1 is required for Aß degradation. Inhibiting elevated miR-17 in 5xFAD mouse microglia improves Aß degradation, autophagy, and NBR1 puncta formation in vitro and improves NBR1 expression in vivo. These findings offer a mechanism behind dysfunctional autophagy in AD microglia which may be useful for therapeutic interventions aiming to improve autophagy function in AD.


Assuntos
Doença de Alzheimer/imunologia , Peptídeos beta-Amiloides/imunologia , Autofagia/imunologia , Regulação da Expressão Gênica/imunologia , MicroRNAs/imunologia , Microglia/imunologia , Proteólise , Animais , Feminino , Humanos , Masculino , Camundongos
6.
Mol Immunol ; 137: 221-227, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34284214

RESUMO

Natural Killer (NK) cells are considered the first line of defense against viral infections and tumors. Several factors affect NK cytotoxic activity rendering it dysfunctional and thereby impeding the ability to scavenge abnormal cells as a part of immune escaping mechanisms induced by different types of cancers. NK cells play a crucial role augmenting the activity of various types of anticancer mAb since dysfunctional NK cells are the main reason for the low response to these therapies. To this light, we examined the phenotypic characters of the circulating NK cells isolated from HCC patients compared to healthy controls. Then, dysfunctional NK cells, from HCC patients, were reactivated with cytokines cocktail and their cytotoxic activity with the anti-EGFR mAb "cetuximab" was investigated. This showed a downregulation of patients NK cells activating receptors (NKP30, NKP46, NKG2D and CD16) as well as CD56 and up-regulation of NKG2A inhibitory receptor. We also reported an increase in aberrant CD56- NK cells subset in peripheral blood of HCC patients compared to healthy controls. Thus, confirming the dysfunctionality of peripheral NK cells isolated from HCC patients. Cytokines re-activation of those NK cells lead to upregulation of NK activating receptors and downregulation of inhibitory receptor. Moreover, the percentage of aberrant CD56- NK cells subset was reduced. Here, we proved that advanced HCC patients have an increased percentage of more immature and noncytotoxic NK cell subsets in their peripheral blood, which might account for the low cytotoxicity noticed in those patients. A significant improvement in the cytotoxicity against HCC was noticed upon using reactivated NK cells combined with cetuximab. Therefore, this study highlights the potential recruitment of NK immune cells along with cetuximab to enhance cytotoxicity against HCC.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Hepatocelular/terapia , Cetuximab/uso terapêutico , Citocinas/farmacologia , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas/terapia , Antígeno CD56/metabolismo , Linhagem Celular Tumoral , Humanos , Ativação Linfocitária/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo
8.
Curr Cancer Drug Targets ; 21(7): 601-607, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34011259

RESUMO

Hepatocellular carcinoma (HCC) is a major health problem worldwide. Most patients are diagnosed for the first time at late stages, which leads to very poor prognosis. It is challenging to discover strategies for treatment at these advanced stages. Recently, monoclonal antibodies (mAbs) targeting specific cellular signaling pathways in HCC have been developed. Unfortunately, they still have a low survival rate, and some of them failed clinically to produce effective responses even if they showed very good results against HCC in preclinical studies. This review focuses on and discusses the possible causes for the failure of mAbs, precisely anti-Epidermal Growth Factor Receptor (EGFR) mAb and the crosstalk between this mAb and patients' NK cells.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Citotoxicidade Celular Dependente de Anticorpos , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Células Matadoras Naturais , Neoplasias Hepáticas/tratamento farmacológico , Falha de Tratamento
9.
Sci Rep ; 11(1): 855, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441602

RESUMO

Burkholderia cenocepacia (B. cenocepacia) is an opportunistic bacterium; causing severe life threatening systemic infections in immunocompromised individuals including cystic fibrosis patients. The lack of gasdermin D (GSDMD) protects mice against endotoxin lipopolysaccharide (LPS) shock. On the other hand, GSDMD promotes mice survival in response to certain bacterial infections. However, the role of GSDMD during B. cenocepacia infection is not yet determined. Our in vitro study shows that GSDMD restricts B. cenocepacia replication within macrophages independent of its role in cell death through promoting mitochondrial reactive oxygen species (mROS) production. mROS is known to stimulate autophagy, hence, the inhibition of mROS or the absence of GSDMD during B. cenocepacia infections reduces autophagy which plays a critical role in the restriction of the pathogen. GSDMD promotes inflammation in response to B. cenocepacia through mediating the release of inflammasome dependent cytokine (IL-1ß) and an independent one (CXCL1) (KC). Additionally, different B. cenocepacia secretory systems (T3SS, T4SS, and T6SS) contribute to inflammasome activation together with bacterial survival within macrophages. In vivo study confirmed the in vitro findings and showed that GSDMD restricts B. cenocepacia infection and dissemination and stimulates autophagy in response to B. cenocepacia. Nevertheless, GSDMD promotes lung inflammation and necrosis in response to B. cenocepacia without altering mice survival. This study describes the double-edged functions of GSDMD in response to B. cenocepacia infection and shows the importance of GSDMD-mediated mROS in restriction of B. cenocepacia.


Assuntos
Infecções por Burkholderia/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Animais , Autofagia/fisiologia , Infecções por Burkholderia/prevenção & controle , Burkholderia cenocepacia/patogenicidade , Caspases Iniciadoras/genética , Caspases Iniciadoras/metabolismo , Morte Celular , Feminino , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Lipopolissacarídeos/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/fisiologia , Espécies Reativas de Oxigênio/metabolismo
10.
Molecules ; 26(2)2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33477997

RESUMO

(1) Background and Aim: All-trans retinoic acid (ATRA) induces differentiation and inhibits growth of many cancer cells. However, resistance develops rapidly prompting the urgent need for new synthetic and potent derivatives. EC19 and EC23 are two synthetic retinoids with potent stem cell neuro-differentiation activity. Here, these compounds were screened for their in vitro antiproliferative and cytotoxic activity using an array of different cancer cell lines. (2) Methods: MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, AV/PI (annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI)), cell cycle analysis, immunocytochemistry, gene expression analysis, Western blotting, measurement of glutamate and total antioxidant concentrations were recruited. (3) Results: HepG2, Caco-2, and MCF-7 were the most sensitive cell lines; HepG2 (ATRA; 36.2, EC19; 42.2 and EC23; 0.74 µM), Caco-2 (ATRA; 58.0, EC19; 10.8 and EC23; 14.7 µM) and MCF-7 (ATRA; 99.0, EC19; 9.4 and EC23; 5.56 µM). Caco-2 cells were selected for further biochemical investigations. Isobologram analysis revealed the combined synergistic effects with 5-fluorouracil with substantial reduction in IC50. All retinoids induced apoptosis but EC19 had higher potency, with significant cell cycle arrest at subG0-G1, -S and G2/M phases, than ATRA and EC23. Moreover, EC19 reduced cellular metastasis in a transwell invasion assay due to overexpression of E-cadherin, retinoic acid-induced 2 (RAI2) and Werner (WRN) genes. (4) Conclusion: The present study suggests that EC-synthetic retinoids, particularly EC19, can be effective, alone or in combinations, for potential anticancer activity to colorectal cancer. Further in vivo studies are recommended to pave the way for clinical applications.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Retinoides/síntese química , Retinoides/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Células CACO-2 , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Técnicas de Química Sintética , Humanos , Retinoides/química
11.
IUBMB Life ; 73(2): 474-482, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33347699

RESUMO

Hepatocellular carcinoma (HCC) is a major cause of cancer death in Egypt. There is still a risk for HCC development even after eradicating hepatitis C virus (HCV) by direct-acting antivirals (DAAs). Chitinase-3-like-protein-1 (CHI3L1), a biomarker for predicting many diseases, plays an essential role in inflammation, angiogenesis, and antiapoptosis. Tolloid-like protein 1 (TLL1) may be involved in hepatic fibrogenesis and carcinogenesis. This study aimed to determine the role and combined effect of CHI3L1 (rs880633), TLL1 (rs1503298), and an intergenic (rs597533) polymorphisms on the risk of developing HCC in Egyptian patients after achieving sustained virological response (SVR) by DAAs. Blood samples were collected from 68 HCC patients, 77 non-HCC subjects, and 80 healthy controls. The DNA was extracted and analyzed for rs880633, rs1503298, and rs597533 using Genotyping TaqMan™ assay. The result of the present study showed a significant difference in genotypes and alleles frequencies in both (rs880633) and (rs597533) in HCC group as compared to healthy control and also as compared to the non-HCC group. However, regarding to (rs1503298) genotypes and alleles between the HCC and non-HCC groups, there were no significant differences. Combined polymorphism in more than one gene simultaneously showed a higher risk to HCC after SVR than an individual locus. Both allelic and genotypic variations of the CHI3L1 gene (rs880633) and an intergenic (rs597533) seemed to be significant predictors confirming a great risk for HCC susceptibility in Egyptian patients achieved SVR. Patients with a polymorphism in more than one gene showed an increased risk to HCC after SVR rather than individual locus.


Assuntos
Antivirais/farmacologia , Carcinoma Hepatocelular/diagnóstico , Proteína 1 Semelhante à Quitinase-3/genética , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Polimorfismo de Nucleotídeo Único , Metaloproteases Semelhantes a Toloide/genética , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Feminino , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade
12.
Curr Cancer Drug Targets ; 20(10): 768-778, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32619170

RESUMO

NUPR1 is a transcription factor that has attracted great attention because of its various roles in cancer. Several studies were carried out to determine its molecular targets and mechanism of action to develop novel therapies against cancer. Here, we shed light on the role of NUPR1 in different types of cancer. NUPR1 regulates a complex network of pathways that may be affected by its silencing, which can cause varying effects. Its role in some types of cancer has been reported but remains incompletely understood, whereas its roles in other types of cancers have not been reported yet. Therefore, targeting NUPR1 for cancer treatment remains challenging and risky.


Assuntos
Antineoplásicos/uso terapêutico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Humanos , Neoplasias/metabolismo , Neoplasias/patologia
13.
Sci Rep ; 10(1): 8368, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32433577

RESUMO

Pediatric high-grade gliomas (HGG) are rare aggressive tumors that present a prognostic and therapeutic challenge. Diffuse midline glioma, H3K27M-mutant is a new entity introduced to HGG in the latest WHO classification. In this study we evaluated the presence of H3K27M mutation in 105 tumor samples histologically classified into low-grade gliomas (LGG) (n = 45), and HGG (n = 60). Samples were screened for the mutation in histone H3.3 and H3.1 variants to examine its prevalence, prognostic impact, and assess its potential clinical value in limited resource settings. H3K27M mutation was detected in 28 of 105 (26.7%) samples, and its distribution was significantly associated with midline locations (p-value < 0.0001) and HGG (p-value = 0.003). Overall and event- free survival (OS and EFS, respectively) of patients with mutant tumors did not differ significantly, neither according to histologic grade (OS p-value = 0.736, EFS p-value = 0.75) nor across anatomical sites (OS p-value = 0.068, EFS p-value = 0.153). Detection of H3K27M mutation in pediatric gliomas provides more precise risk stratification compared to traditional histopathological techniques. Hence, mutation detection should be pursued in all pediatric gliomas. Meanwhile, focusing on midline LGG can be an alternative in lower-middle-income countries to maximally optimize patients' treatment options.


Assuntos
Neoplasias Encefálicas/mortalidade , Testes Genéticos/normas , Glioma/mortalidade , Histonas/genética , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Tomada de Decisão Clínica/métodos , Análise Mutacional de DNA/normas , Intervalo Livre de Doença , Egito/epidemiologia , Feminino , Seguimentos , Glioma/diagnóstico , Glioma/genética , Glioma/patologia , Humanos , Estimativa de Kaplan-Meier , Lisina/genética , Masculino , Oncologia/normas , Mutação , Gradação de Tumores , Guias de Prática Clínica como Assunto , Prognóstico , Medição de Risco/métodos , Medição de Risco/normas
14.
J Adv Res ; 24: 251-259, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32373358

RESUMO

NS4A is a non-structural multi-tasking small peptide that is essential for HCV maturation and replication. The central odd-numbered hydrophobic residues of NS4A (Val-23' to Leu-31') are essential for activating NS3 upon NS3/4A protease complex formation. This study aims to design new specific allosteric NS3/4A protease inhibitors by mutating Val-23', Ile-25', and Ile-29' into bulkier amino acids. Pep-15, a synthetic peptide, showed higher binding affinity towards HCV-NS3 subtype-4 than native NS4A. The K d of Pep-15 (80.0 ± 8.0 nM) was twice as high as that of native NS4A (169 ± 37 nM). The mutant Pep-15 inhibited the catalytic activity of HCV-NS3 by forming an inactive complex. Molecular dynamics simulations suggested that a cascade of conformational changes occurred, especially in the catalytic triad arrangements, thereby inactivating NS3. A large shift in the position of Ser-139 was observed, leading to loss of critical hydrogen bonding with His-57. Even though this study is not a classic drug discovery study-nor do we propose Pep-15 as a drug candidate-it serves as a stepping stone towards developing a potent inhibitor of hitherto untargeted HCV subtypes.

15.
Biomolecules ; 10(3)2020 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245218

RESUMO

The nonstructural (NS) protein NS3/4A protease is a critical factor for hepatitis C virus (HCV) maturation that requires activation by NS4A. Synthetic peptide mutants of NS4A were found to inhibit NS3 function. The bridging from peptide inhibitors to heterocyclic peptidomimetics of NS4A has not been considered in the literature and, therefore, we decided to explore this strategy for developing a new class of NS3 inhibitors. In this report, a structure-based design approach was used to convert the bound form of NS4A into 1H-imidazole-2,5-dicarboxamide derivatives as first generation peptidomimetics. This scaffold mimics the buried amino acid sequence Ile-25` to Arg-28` at the core of NS4A21`-33` needed to activate the NS3 protease. Some of the synthesized compounds (Coded MOC) were able to compete with and displace NS4A21`-33` for binding to NS3. For instance, N5-(4-guanidinobutyl)-N2-(n-hexyl)-1H-imidazole-2,5-dicarboxamide (MOC-24) inhibited the binding of NS4A21`-33` with a competition half maximal inhibitory concentration (IC50) of 1.9 ± 0.12 µM in a fluorescence anisotropy assay and stabilized the denaturation of NS3 by increasing the aggregation temperature (40% compared to NS4A21`-33`). MOC-24 also inhibited NS3 protease activity in a fluorometric assay. Molecular dynamics simulations were conducted to rationalize the differences in structure-activity relationship (SAR) between the active MOC-24 and the inactive MOC-26. Our data show that MOC compounds are possibly the first examples of NS4A peptidomimetics that have demonstrated promising activities against NS3 proteins.


Assuntos
Hepatite C/enzimologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptidomiméticos/química , Inibidores de Serina Proteinase/química , Proteínas não Estruturais Virais/química , Peptidomiméticos/síntese química , Inibidores de Serina Proteinase/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores
16.
Regul Toxicol Pharmacol ; 113: 104622, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32087353

RESUMO

The benchmark of this study is to evaluate the radio protective efficiency of diosmin, a natural citrus flavone of hesperidin derivative on radiation-induced damage in wistar albino rats. Rats orally administered two diosmin doses (100 and 200 mg/kg body wt.) for a month (every other day) prior to exposure to high gamma radiation single dose (8Gy) or cumulative dose (10Gy). To evaluate the radio protective efficiency of diosmin various biochemical estimations, histopathological alterations as well as comet assay and caspase-3 activity for assessment of apoptosis were performed. Results indicated that radiation-induced decline in the levels of antioxidant parameters (SOD and GSH), increased lipid peroxidation, DNA damage and apoptosis were improved by pre-administration of diosmin. Diosmin dose (200 mg/kg body wt.) restored the antioxidant status to near normal and reduced lipid peroxidation, DNA and tissue damage. These results were confirmed by histopathological examinations, which showed that pre-administration of diosmin protected the liver and kidney of albino rats against gamma-irradiation induced damage. Hence, it has been illustrated that diosmin might be an effective radio protector against radiation-induced damage in rats. Moreover, diosmin alone pretreated group did not show any biochemical alterations or DNA damage indicating the protective nature of the drug.


Assuntos
Diosmina/farmacologia , Raios gama , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Administração Oral , Animais , Apoptose/efeitos dos fármacos , Dano ao DNA , Diosmina/administração & dosagem , Diosmina/química , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/química , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
17.
PLoS Pathog ; 15(12): e1008139, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31815959

RESUMO

Prion or PrPSc is the proteinaceous infectious agent causing prion diseases in various mammalian species. Despite decades of research, the structural basis for PrPSc formation and prion infectivity remains elusive. To understand the role of the hydrophobic region in forming infectious prion at the molecular level, we report X-ray crystal structures of mouse (Mo) prion protein (PrP) (residues 89-230) in complex with a nanobody (Nb484). Using the recombinant prion propagation system, we show that the binding of Nb484 to the hydrophobic region of MoPrP efficiently inhibits the propagation of proteinase K resistant PrPSc and prion infectivity. In addition, when added to cultured mouse brain slices in high concentrations, Nb484 exhibits no neurotoxicity, which is drastically different from other neurotoxic anti-PrP antibodies, suggesting that the Nb484 can be a potential therapeutic agent against prion disease. In summary, our data provides the first structure-function evidence supporting a crucial role of the hydrophobic region of PrP in forming an infectious prion.


Assuntos
Proteínas PrPSc/química , Proteínas PrPSc/efeitos dos fármacos , Proteínas Priônicas/química , Proteínas Priônicas/efeitos dos fármacos , Anticorpos de Domínio Único/farmacologia , Animais , Camundongos , Conformação Proteica , Domínios Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade
18.
J Drug Assess ; 8(1): 115-121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31231590

RESUMO

Background: The incidence of Type 2 Diabetes Mellitus (T2DM) in Egypt is considered one of the highest in the world. Metformin and Sulfonylureas are usually prescribed together due to their efficacy and their relatively low cost. Organic cation transport 1, encoded by SLC22A1 gene, is the main transporter of metformin into hepatocytes, which is considered metformin site of action. Sulfonylureas enhance insulin release from pancreatic B-cells through binding to sulfonylurea receptor 1, encoded by ABCC8 gene. Single nucleotide polymorphisms in the SLC22A1 and ABCC8 genes might affect the response of each drug. Aims: To investigate the influence of SLC22A1 rs622342 (A>C) and ABCC8 rs757110 (A>C) genetic variants on the efficacy of metformin and glimepiride combination therapy in Egyptian T2DM patients. Methods: Observational cross-sectional study in which patients receiving metformin and glimepiride combination therapy for at least 6 months were included for genotyping and classified into either responders or non-responders, based on their HbA1C level. Results: A total of 127 patients were included and genotyped. They were divided into 93 responders (HbA1C<7%) and 34 non-responders (HbA1C≥7%). Minor allele frequencies for rs622342 and rs757110 were 0.189 and 0.271, respectively. Only SLC22A1 rs622342 variant was found to be associated with the response of combination therapy, in which AA alleles carriers were 2.7-times more responsive to metformin than C allele carriers (Recessive model, odds ratio = 2.718, p = 0.025, 95% CI = 1.112-6.385). Conclusion: Genotyping of rs622342 can be useful in predicting the response to metformin in combination therapy in Egyptian T2DM patients.

19.
Mediators Inflamm ; 2019: 3273645, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30728751

RESUMO

Chronic inflammation is a pivotal contributor to the liver damage mediated by hepatitis C virus (HCV). The NOD-like receptor, pyrin domain-containing 3 (NLRP3) inflammasome is activated by HCV in both hepatocytes and Kupffer cells. The aim of our study was to investigate the association of nine single-nucleotide polymorphisms in four inflammasome genes (NLRP3, CARD8, IL-1ß, and IL-18) with the susceptibility to HCV infection and outcome of interferon treatment in 201 Egyptian chronic hepatitis C patients and 95 healthy controls. The genotyping was conducted using TaqMan predesigned SNP assay. In the comparative analysis, the CC genotype of the NLRP3 rs1539019 was found to be associated with the lower risk to chronic HCV infection (OR: 0.33, 95% CI: 0.17-0.62). This association was also found for the CA genotype and the A allele of the NLRP3 rs35829419 (OR: 0.18 and 0.22, respectively), in addition to the GG genotype and G allele of IL-18 rs1946518 (OR: 0.55 and 0.61, respectively). In contrast, the AA genotype of the IL-1ß rs1143629 was significantly more frequent in HCV patients (OR: 1.7, 95% CI: 1-2.86). Notably, the frequency of the AA genotype of NLRP3 rs1539019 was significantly higher in patients with lack of response (NR) to the interferon treatment (OR: 1.95, 95% CI: 1-3.7). A similar association was found for both the CC genotype and C allele of the NLRP3 rs35829419 (OR: 2.78 and 2.73, respectively) and for the TT genotype and T allele of CARD8 rs2043211 (OR: 2.64 and 1.54, respectively). Yet, the IL-1ß (rs1143629, rs1143634) and IL-18 (rs187238, rs1946518) polymorphisms did not show any significant association with response to interferon treatment. In conclusion, this study reports, for the first time, the association of genetic variations in NLRP3 with hepatitis C susceptibility and response to treatment in Egyptian patients. However, further large-scale studies are recommended to confirm our findings.


Assuntos
Hepatite C Crônica/genética , Hepatite C Crônica/terapia , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Polimorfismo Genético , Adulto , Alelos , Antivirais/uso terapêutico , Proteínas Adaptadoras de Sinalização CARD/genética , Estudos de Casos e Controles , Egito , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Inflamação , Interleucina-18/genética , Interleucina-1beta/genética , Desequilíbrio de Ligação , Masculino , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco
20.
Eur J Pharm Sci ; 127: 102-114, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30366078

RESUMO

Viral gastroenteritis is a major global public-health threat. All age groups are susceptible for this infection, but its most serious consequences affect children. Rotavirus, Coxsackievirus and Adenovirus are the most common viruses that cause gastroenteritis. Herein, we synthesized novel pyrrole, pyrrolo[2,3­d]pyrimidine and pyrrolo[3,2­e][1,2,4]triazolo[4,3­c]pyrimidine derivatives. The non-toxic doses of these compounds were determined using BGM cell lines. We examined all the new compounds for their anti-viral activities against Rotavirus Wa strain and Coxsackievirus B4. Compounds 2a, 2d, 5a, 5c, 5d, 7b, 7j, 7n, 14b, 14c, 14e and 14f exhibited significant antiviral activity. We interpreted the action of these compounds using molecular docking against the homology models of viral polymerase enzymes of these viruses. RMSD value of 5d/Coxsackievirus was higher than the RMSD value for 5d/rotavirus and hence better as a stability parameter, which can be correlated to the biological activity.


Assuntos
Antivirais/farmacologia , Enterovirus Humano B/efeitos dos fármacos , Pirimidinas/farmacologia , Pirróis/farmacologia , Rotavirus/efeitos dos fármacos , Animais , Antivirais/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Infecções por Coxsackievirus , Simulação de Acoplamento Molecular , Pirimidinas/química , Pirróis/química , Infecções por Rotavirus
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