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1.
Metab Brain Dis ; 39(1): 29-42, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38153584

RESUMO

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental condition characterized by altered brain connectivity and function. In this study, we employed advanced bioinformatics and explainable AI to analyze gene expression associated with ASD, using data from five GEO datasets. Among 351 neurotypical controls and 358 individuals with autism, we identified 3,339 Differentially Expressed Genes (DEGs) with an adjusted p-value (≤ 0.05). A subsequent meta-analysis pinpointed 342 DEGs (adjusted p-value ≤ 0.001), including 19 upregulated and 10 down-regulated genes across all datasets. Shared genes, pathogenic single nucleotide polymorphisms (SNPs), chromosomal positions, and their impact on biological pathways were examined. We identified potential biomarkers (HOXB3, NR2F2, MAPK8IP3, PIGT, SEMA4D, and SSH1) through text mining, meriting further investigation. Additionally, we shed light on the roles of RPS4Y1 and KDM5D genes in neurogenesis and neurodevelopment. Our analysis detected 1,286 SNPs linked to ASD-related conditions, of which 14 high-risk SNPs were located on chromosomes 10 and X. We highlighted potential missense SNPs associated with FGFR inhibitors, suggesting that it may serve as a promising biomarker for responsiveness to targeted therapies. Our explainable AI model identified the MID2 gene as a potential ASD biomarker. This research unveils vital genes and potential biomarkers, providing a foundation for novel gene discovery in complex diseases.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/genética , Biomarcadores , Encéfalo , Genômica , Antígenos de Histocompatibilidade Menor , Histona Desmetilases
2.
J Theor Biol ; 469: 163-171, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-30844370

RESUMO

The G2019S substitution in the Leucine-rich repeat kinase 2 (LRRK2) is significantly associated with Parkinson's disease (PD). This substitution was identified in both familial and sporadic forms of PD with a higher frequency. Few computational studies have reported the impact of G2019S substitution on inhibitors of the kinase domain of LRRK2. However, no computational study deeply investigated the possible impact of the G2019S substitution on the kinase domain in its Apo conformation. Therefore, in this study, we used 200 ns molecular dynamic simulation using the GROMACS 5.1.4 package software to investigate the impact of the G2019S substitution on the structure of the kinase domain of LRRK2. Our results indicate that the G2019S substitution affects the dynamics and stability of LRRK2 by decreasing the flexibility and increasing the compactness of the kinase domain and showing its tendency to be in an active conformation for long time interval because of the high energy barrier between active and inactive conformation. This study predicts the molecular pathogenicity mechanism of the G2019S on patients with PD and provides a potential platform for developing therapeutics for patients with PD that harbor this amino acid substitution.


Assuntos
Substituição de Aminoácidos/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/química , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Simulação de Dinâmica Molecular , Doença de Parkinson/genética , Humanos , Ligação de Hidrogênio , Análise de Componente Principal , Domínios Proteicos , Estrutura Secundária de Proteína , Solventes , Termodinâmica
3.
Diabetes Metab Res Rev ; 34(7): e3026, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29774648

RESUMO

The aim of this study was to conduct a systematic review and meta-analysis and determine the prevalence of diabetic nephropathy (DN) among Arab patients with T1D. A systematic literature search was conducted using 4 different literature databases (PubMed, ScienceDirect, Web of Science, and Embase) to capture all relevant data about Arab patients with T1D that had DN. Meta-analysis and systematic review were performed using the random effect model, and the heterogeneity of the studies was assessed using the Q-test, I2, and Tau-squared statistics. Publication bias was assessed using the funnel-plot test. Our search strategy captured 372 studies in only 10 out of the 22 Arab countries in a period of 48 years (1969-2017); of which, 41 met our inclusion criteria for full article analysis, of those, 15 were eligible for meta-analysis. We estimated the prevalence of DN among Arab people with T1D to be 18.2% (95% confidence interval 13.1%-24.8%). In conclusion, DN prevalence is underexplored among Arab patients with T1D and represents a significant risk for the well-being of Arab patients with T1D. Therefore, there is an urgent need for comprehensive epidemiological studies for DN among Arab patients with T1D.


Assuntos
Árabes/estatística & dados numéricos , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Nefropatias Diabéticas/epidemiologia , Mundo Árabe , Humanos , Oriente Médio/epidemiologia , Prevalência
4.
Bioorg Med Chem Lett ; 25(24): 5767-71, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26546218

RESUMO

A series of novel substituted-[(3R)-amino-2-(2,5-difluorophenyl)]tetrahydro-2H-pyran analogs have been prepared and evaluated as potent, selective and orally active DPP-4 inhibitors. These efforts lead to the discovery of a long acting DPP-4 inhibitor, omarigliptin (MK-3102), which recently completed phase III clinical development and has been approved in Japan.


Assuntos
Amidas/química , Inibidores da Dipeptidil Peptidase IV/química , Compostos Heterocíclicos com 2 Anéis/química , Piranos/química , Sulfonamidas/química , Animais , Sítios de Ligação , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/síntese química , Inibidores da Dipeptidil Peptidase IV/farmacocinética , Cães , Meia-Vida , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/farmacocinética , Simulação de Acoplamento Molecular , Estrutura Terciária de Proteína , Piranos/síntese química , Piranos/farmacocinética , Ratos , Relação Estrutura-Atividade
5.
J Nanobiotechnology ; 13: 74, 2015 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-26498972

RESUMO

Diabetic cases have increased rapidly in recent years throughout the world. Currently, for type-1 diabetes mellitus (T1DM), multiple daily insulin (MDI) injections is the most popular treatment throughout the world. At this juncture, researchers are trying to develop different insulin delivery systems, especially through oral and pulmonary route using nanocarrier based delivery system. This next generation efficient therapy for T1DM may help to improve the quality of life of diabetic patients who routinely employ insulin by the subcutaneous route. In this paper, we have depicted various next generation nanocarrier based insulin delivery systems such as chitosan-insulin nanoparticles, PLGA-insulin nanoparticles, dextran-insulin nanoparticles, polyalkylcyanoacrylated-insulin nanoparticles and solid lipid-insulin nanoparticles. Modulation of these insulin nanocarriers may lead to successful oral or pulmonary insulin nanoformulations in future clinical settings. Therefore, applications and limitations of these nanoparticles in delivering insulin to the targeted site have been thoroughly discussed.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Insulina/uso terapêutico , Nanopartículas/química , Administração Oral , Portadores de Fármacos/química , Humanos
6.
Int J Mol Sci ; 15(4): 5472-95, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24686518

RESUMO

Wingless-type (Wnt) signaling proteins participate in various cell developmental processes. A suppressive role of Wnt5a on keratinocyte growth has already been observed. However, the role of other Wnt proteins in proliferation and differentiation of keratinocytes remains unknown. Here, we investigated the effects of the Wnt ligand, Wnt3a, on proliferation and differentiation of keratinocytes. Keratinocytes from normal human skin were cultured and treated with recombinant Wnt3a alone or in combination with the inflammatory cytokine, tumor necrosis factor α (TNFα). Furthermore, using bioinformatics, we analyzed the biochemical parameters, molecular evolution, and protein-protein interaction network for the Wnt family. Application of recombinant Wnt3a showed an anti-proliferative effect on keratinocytes in a dose-dependent manner. After treatment with TNFα, Wnt3a still demonstrated an anti-proliferative effect on human keratinocytes. Exogenous treatment of Wnt3a was unable to alter mRNA expression of differentiation markers of keratinocytes, whereas an altered expression was observed in TNFα-stimulated keratinocytes. In silico phylogenetic, biochemical, and protein-protein interaction analysis showed several close relationships among the family members of the Wnt family. Moreover, a close phylogenetic and biochemical similarity was observed between Wnt3a and Wnt5a. Finally, we proposed a hypothetical mechanism to illustrate how the Wnt3a protein may inhibit the process of proliferation in keratinocytes, which would be useful for future researchers.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Queratinócitos/citologia , Proteína Wnt3A/metabolismo , Proteína Wnt3A/farmacologia , Sequência de Aminoácidos , Sobrevivência Celular , Células Cultivadas , Biologia Computacional , Evolução Molecular , Humanos , Interações Hidrofóbicas e Hidrofílicas , Antígeno Ki-67/biossíntese , Antígeno Ki-67/genética , Filogenia , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas/genética , Psoríase/patologia , RNA Mensageiro/biossíntese , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Fator de Necrose Tumoral alfa/farmacologia , Proteínas Wnt/genética , Via de Sinalização Wnt/genética , Proteína Wnt-5a , Proteína Wnt3A/genética
7.
ACS Omega ; 9(14): 16288-16302, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617633

RESUMO

Targeted therapy revolutionizes the treatment of non-small-cell lung cancer (NSCLC), harboring molecular change. Epidermal growth factor receptor(EGFR) mutations play a crucial role in the development of NSCLC, serving as a pivotal factor in its pathogenesis. We elucidated the mechanisms of resistance and potential therapeutic strategies in NSCLC resistant to the EGFR-tyrosine kinase inhibitor (EGFR-TKI). This is achieved by identifying rare missense variants through whole exome sequencing (WES). The goal is to enhance our understanding, identify biomarkers, and lay the groundwork for targeted interventions, thereby offering hope for an improved NSCLC treatment landscape. We conducted WES analysis on 16 NSCLC samples with EGFR-TKI-resistant NSCLC obtained from SRA-NCBI (PRJEB50602) to reveal genomic profiles within the EGFR-TKI. Our findings showed that 48% of the variants were missense, and after filtering with the Ensembl variant effect predictor, 53 rare missense variants in 23 genes were identified as highly deleterious. Further examination using pathogenic tools like PredictSNP revealed 12 deleterious rare missense variants in 7 genes: ZNF717, PSPH, ESRRA, SEMA3G, PTPN7, CAVIN4, and MYBBP1A. Molecular dynamics simulation (MDS) suggested that the L385P variant alters the structural flexibility of ESRRA, potentially leading to unfolding of ERRα proteins. This could impact their function and alter ERRα expression. These insights from MDS enhance our understanding of the structural and dynamic consequences of the L385P ESRRA variant and provide valuable implications for subsequent therapeutic considerations and targeted interventions.

8.
Environ Sci Process Impacts ; 26(7): 1130-1146, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38655700

RESUMO

Despite a significant amount of research on micronanoplastics (MNPs), there is still a gap in our understanding of their function as transporters of other environmental pollutants (known as the Trojan horse effect) and the combined effects of ingestion, bioaccumulation, and toxicity to organisms. This study examined the individual effects of polystyrene nanoplastics (PSNPs) with various surface functionalizations (plain (PS), carboxylated (PS-COOH), and aminated (PS-NH2)), particle sizes (100 nm and 500 nm), and a pharmaceutical co-contaminant (metformin hydrochloride (MH), an anti-diabetic drug) on the marine crustacean - Artemia salina. The study specifically aimed to determine if MH alters the detrimental effects of PSNPs on A. salina. The potential toxicity of these emerging pollutants was assessed by examining mortality, hatching rate, morphological changes, and biochemical changes. Smaller nanoparticles had a more significant impact than larger ones, and PS-NH2 was more harmful than PS and PS-COOH. Exposure to the nanoparticle complex with MH resulted in a decrease in hatching rate, an increase in mortality, developmental abnormalities, an increase in reactive oxygen species, catalase, and lipid peroxidase, and a decrease in total protein and superoxide dismutase, indicating a synergistic effect. There were no significant differences between the complex and the individual nanoparticles. However, accumulating these particles in organisms could contaminate the food chain. These results highlight the potential environmental risks associated with the simultaneous exposure of aquatic species to plastics, particularly smaller PS, aminated PS, and pharmaceutical complex PS.


Assuntos
Artemia , Tamanho da Partícula , Poluentes Químicos da Água , Animais , Artemia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Nanopartículas/toxicidade , Microplásticos/toxicidade , Poliestirenos/toxicidade , Metformina/toxicidade
9.
ACS Omega ; 9(23): 24379-24395, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38882157

RESUMO

Breast cancer (BC) is globally recognized as the second most prevalent form of cancer. It predominantly affects women and can be categorized into distinct types based on the overexpression of specific cancer receptors.The key receptors implicated in this context are the human epidermal growth factor receptor-2 (HER2), estrogen receptor (ER), and progesterone receptor (PR), alongside a particularly intricate subclass known as triple-negative breast cancer (TNBC). This subclassification is critical for the stratification of breast cancer and informs therapeutic decision-making processes. Due to a lack of therapeutic targets, such as growth factor receptors, TNBC is the most aggressive type. Hence, identifying targetable regulators such as miRNAs could pave the way for potential therapeutic interventions. To identify common differentially expressed mRNAs (DE-mRNAs) in BC, including TNBC, we leveraged two data sets from the GEO collection and The Cancer Genome Atlas (TCGA). Significant DE-mRNAs were identified through PPI, MCODE, CytoNCA, and CytoHubba analyses. Following this, miRNAs were predicted using mirDIP. We utilized GSE42568, GSE185645, and TCGA and identified 159 common DE-mRNAs. Using Cytoscape plug-ins, we identified the 10 most significant DE-mRNAs in BC. Using mirDIP, target miRNAs for 10 DE-mRNAs were identified. We conducted an advanced analysis on the TNBC GEO data set (GSE45498) to corroborate the significance of shared DE-mRNAs and DE-miRNAs in TNBC. We identified four downregulated DE-miRNAs, including hsa-miR-802, hsa-miR-1258, hsa-miR-548a-3p, and hsa-miR-2053, significantly associated with TNBC. Our study revealed significant miRNA-mRNA interactions, specifically hsa-miR-802/MELK, hsa-miR-1258/NCAPG, miR-548a-3p/CCNA2, and hsa-miR-2053/NUSAP1, in both BC and TNBC. The observed downregulation of hsa-miR-548a-3p is associated with diminished survival rates in BC patients, emphasizing their potential utility as prognostic indicators. Furthermore, the differential expression of mRNAs, including CCNB2, UBE2C, MELK, and KIF2C, correlates with reduced survival outcomes, signifying their critical role as potential targets for therapeutic intervention in both BC and TNBC. These findings highlight specific regulatory mechanisms that are potentially crucial for understanding and treating these cancer types.

10.
Front Biosci (Landmark Ed) ; 29(6): 220, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38940026

RESUMO

BACKGROUND: The incidence rate of oropharyngeal squamous cell carcinoma (OPSCC) worldwide is alarming. In the clinical community, there is a pressing necessity to comprehend the etiology of the OPSCC to facilitate the administration of effective treatments. METHODS: This study confers an integrative genomics approach for identifying key oncogenic drivers involved in the OPSCC pathogenesis. The dataset contains RNA-Sequencing (RNA-Seq) samples of 46 Human papillomavirus-positive head and neck squamous cell carcinoma and 25 normal Uvulopalatopharyngoplasty cases. The differential marker selection is performed between the groups with a log2FoldChange (FC) score of 2, adjusted p-value < 0.01, and screened 714 genes. The Particle Swarm Optimization (PSO) algorithm selects the candidate gene subset, reducing the size to 73. The state-of-the-art machine learning algorithms are trained with the differentially expressed genes and candidate subsets of PSO. RESULTS: The analysis of predictive models using Shapley Additive exPlanations revealed that seven genes significantly contribute to the model's performance. These include ECT2, LAMC2, and DSG2, which predominantly influence differentiating between sample groups. They were followed in importance by FAT1, PLOD2, COL1A1, and PLAU. The Random Forest and Bayes Net algorithms also achieved perfect validation scores when using PSO features. Furthermore, gene set enrichment analysis, protein-protein interactions, and disease ontology mining revealed a significant association between these genes and the target condition. As indicated by Shapley Additive exPlanations (SHAPs), the survival analysis of three key genes unveiled strong over-expression in the samples from "The Cancer Genome Atlas". CONCLUSIONS: Our findings elucidate critical oncogenic drivers in OPSCC, offering vital insights for developing targeted therapies and enhancing understanding its pathogenesis.


Assuntos
Biomarcadores Tumorais , Neoplasias Orofaríngeas , Humanos , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/virologia , Biomarcadores Tumorais/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Inteligência Artificial , Regulação Neoplásica da Expressão Gênica , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Algoritmos , Análise de Sequência de RNA/métodos , Aprendizado de Máquina , Papillomaviridae/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia
11.
ACS Omega ; 8(46): 43856-43872, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38027370

RESUMO

Anaplastic lymphoma kinase (ALK) rearrangements occur in about 5% of nonsmall cell lung cancer (NSCLC) patients. Despite being first recognized as EML4-ALK, fusions with several additional genes have been identified, all of which cause constitutive activation of the ALK kinase and subsequently lead to tumor development. ALK inhibitors first-line crizotinib, second-line ceritinib, and alectinib are effective against NSCLC patients with these rearrangements. Patients progressing on crizotinib had various mutations in the ALK kinase domain. ALK fusion proteins are activated by oligomerization through the fusion partner, which leads to the autophosphorylation of the kinase's domain and consequent downstream activation. The proposed computational study focuses on understanding the activation mechanism of ALK and ATP binding of wild-type (WT) and I1171N/S/T mutations. We analyzed the conformational change of ALK I1171N/S/T mutations and ATP binding using molecular docking and molecular dynamics simulation approaches. According to principal component analysis and free energy landscape, it is clear that I1171N/S/T mutations in Apo and ATP showed different energy minima/unstable structures compared to WT-Apo. The results revealed that I1171N/S/T mutations and ATP binding significantly supported a change toward an active-state conformation, whereas WT-Apo remained inactive. We demonstrated that I1171N/S/T mutations are persistent in an active state and independent of ATP. The I1171S/T mutations showed greater intermolecular H-bonds with ATP than WT-ATP. The molecular mechanics Poisson-Boltzmann surface area analysis revealed that the I1171N/S/T mutation binding energy was similar to that of WT-ATP. This study shows that I1171N/S/T can form stable bonds with ATP and may contribute to a constitutively active kinase. Based on the Y1278-C1097 H-bond and E1167-K1150 salt bridge interaction, I1171N strongly promotes the constitutively active kinase independent of ATP. This structural mechanism study will aid in understanding the oncogenic activity of ALK and the basis for improving the ALK inhibitors.

12.
Front Mol Biosci ; 10: 1306046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38274094

RESUMO

Background: In non-small-cell lung cancer (NSCLC), a pivotal factor in promoting cancer development is the rearrangement in the anaplastic lymphoma kinase ALK gene, resulting in elevated ALK protein expression. F1174C/L/V is the acquired secondary resistant mutation in ALK. Significant survival improvements have been seen while tyrosine kinase inhibitors specifically target ALK. Nevertheless, the emergence of drug resistance hinders the clinical effectiveness of these drugs. Objective: This research sought to find the binding affinity/inhibitory effects of the existing drug lorlatinib (LOR) and upcoming TPX-0131 (zotizalkib/TPX) and repotrectinib (TPX-0005/REP) inhibitors against ALK F1174C/L/V mutations using computational approaches to identify potential strategies over resistance. Methods: We conducted molecular docking, molecular dynamics simulation, and MMPBSA calculations to investigate how compact macrocyclic inhibitors, such as TPX-0131 and repotrectinib, fit within the ATP-binding boundary and differ from LOR. Results: Our results demonstrated that TPX-0131 and repotrectinib contributed to higher binding energy in F1174C and F1174L mutations than LOR. Repotrectinib showed greater binding energy in the F1174V mutation, whereas LOR and TPX-0131 exhibited similar binding energy. However, all three inhibitors showed significant binding energy toward F1174C/L/V mutations found in NSCLC. Conclusion: This comparative study of the potential binding effects of fourth-generation inhibitors TPX-0131 and repotrectinib and third-generation inhibitor LOR for ALK F1174C/L/V mutations revealed the atomistic insights of the binding mechanism. These computational findings enable us to carry out further research for the clinical implementation of fourth-generation ALK inhibitors on ALK-positive NSCLC.

13.
PLoS One ; 18(2): e0282013, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36800372

RESUMO

BACKGROUND: In the economy of therapeutic monitoring, an affordable viral marker is essential in the era of direct-acting antivirals (DAAs). We elucidated the kinetics of HCVcAg to delineate its precise role in monitoring therapeutic response. METHODS: In this longitudinal study, 3208 patients were tested for HCV RNA. A total of 423 patients were started on DAAs. Treatment response and kinetics of HCVcAg/RNA were assessed in treatment-naïve (n = 383) and previously treated (n = 40) patients with follow-up for 2 years. RESULTS: After the initiation of DAAs, the rate of relapse was significantly higher in the previously treated group than naive group [12.5% (5/40) Vs 2% (7/383), p<0.0001]. The response rate at RVR was significantly higher with HCVcAg than RNA in both groups (p<0.02). The kinetics of HCVcAg and RNA were significantly different at ETR and SVR12 in the naïve (p<0.04), but similar at all therapeutic points in the previously treated group. The correlation between HCVcAg and RNA was good at baseline, ETR and SVR, except RVR in both groups (r>0.6; p<0.0001). Furthermore, HCV genotypes, treatment regimen, CTP (<7/≥7) and MELD (<15/≥15) did not influence the therapeutic response and the viral replication kinetics (p>0.05). CONCLUSIONS: It is the first longitudinal study from India shows that the response rate and kinetics of HCVcAg are comparable to HCV RNA for an extended duration, except at RVR, irrespective of the HCV genotypes, treatment regimen, and liver disease severity. Hence, HCVcAg can be considered as a pragmatic marker to monitor therapeutic response and predict relapse in the era of DAAs.


Assuntos
Antivirais , Hepatite C Crônica , Humanos , Antivirais/uso terapêutico , Estudos Longitudinais , RNA Viral/genética , Hepacivirus/genética , Antígenos da Hepatite C , Hepatite C Crônica/tratamento farmacológico , Recidiva , Genótipo
14.
Chem Res Toxicol ; 25(11): 2368-77, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-22998117

RESUMO

As part of our efforts to develop safer selective estrogen receptor modulators (SERMs), compound I {(2S,3R)-(+)-3-(3-hydroxyphenyl)-2-[4-(2-pyrrolidin-1-ylethoxy)-phenyl]-2,3-dihydro-1,4-benzoxathiin-6-ol} was previously identified as a lead for further development. Subsequent studies showed that compound I is genotoxic in both in vitro Chinese hamster ovary (CHO) cells and in vivo mouse studies. To better understand the possible mechanisms for the observed genetoxicity effects, in vitro incubations of I with liver microsomes of human, monkey, and mouse in the presence of adenine were performed, which led to the detection of five adenine adducts. The formation of these adducts was NADPH-dependent, suggesting the involvement of oxidative bioactivation catalyzed by cytochrome P450 enzymes. The mechanism for the formation of the major adenine adduct (A1) involves the formation of a reactive ring-opened para-quinone intermediate. The formation of four other adenine adducts may involve the formation of a reactive epoxide or ortho-quinone intermediate. Furthermore, incubations of compound I with human hepatocytes showed dose-dependent DNA damages in Comet assays. All of the above suggest that some reactive metabolites of compound I, formed through bioactivation mechanisms, have a potential to interact with DNA molecules in vitro and in vivo. This may be one of the causes of the genotoxicity observed preclinically both in vitro and in vivo. This case study demonstrated an approach using in vitro DNA trapping assays for assessing the genotoxicity potential of drug candidates.


Assuntos
Adenina/química , Citocromo P-450 CYP3A/metabolismo , Adutos de DNA/química , Moduladores de Receptor Estrogênico/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Microssomos Hepáticos/metabolismo , Oxati-Inas/farmacologia , Pirrolidinas/farmacologia , Adenina/análogos & derivados , Adenina/metabolismo , Animais , Biocatálise , Células CHO , Cricetinae , Citocromo P-450 CYP3A/química , Adutos de DNA/metabolismo , Dano ao DNA , Relação Dose-Resposta a Droga , Moduladores de Receptor Estrogênico/química , Moduladores de Receptor Estrogênico/metabolismo , Haplorrinos , Camundongos , Microssomos Hepáticos/química , Estrutura Molecular , Oxati-Inas/química , Oxati-Inas/metabolismo , Oxirredução , Pirrolidinas/química , Pirrolidinas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade
15.
Bioorg Med Chem Lett ; 21(6): 1865-70, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21353541

RESUMO

A novel class of human ß(3)-adrenergic receptor agonists was designed in effort to improve selectivity and metabolic stability versus previous disclosed ß(3)-AR agonists. As observed, many of the ß(3)-AR agonists seem to need the acyclic ethanolamine core for agonist activity. We have synthesized derivatives that constrained this moiety by introduction of a pyrrolidine. This unique modification maintains human ß(3) functional potency with improved selectivity versus ancillary targets and also eliminates the possibility of the same oxidative metabolites formed from cleavage of the N-C bond of the ethanolamine. Compound 39 exhibited excellent functional ß(3) agonist potency across species with good pharmacokinetic properties in rat, dog, and rhesus monkeys. Early de-risking of this novel pyrrolidine core (44) via full AMES study supports further research into various new ß(3)-AR agonists containing the pyrrolidine moiety.


Assuntos
Agonistas Adrenérgicos beta/química , Agonistas Adrenérgicos beta/farmacologia , Pirrolidinas/química , Receptores Adrenérgicos beta 3/efeitos dos fármacos , Cristalografia por Raios X , Descoberta de Drogas , Humanos , Modelos Moleculares
16.
Pharmaceuticals (Basel) ; 14(3)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809034

RESUMO

Though it was once known that upregulated Cannabinoid Receptor (CB1) and downregulated Fatty Acid Amide Hydrolase (FAAH1) are associated with tumour aggressiveness and metastasis, it is now clear that upregulated CB1 levels more than a certain point cause accumulation of ceramide and directs cells to apoptosis. Hence, CB1 analogues/FAAH1 blockers are explored widely as anticancer drugs. There are reports on CB1-agonists and FAAH1-blockers separately, however, dual activities along with ovarian cancer-specific links are not established for any natural compound. With this setting, we describe for the first time the isolation of 3-hydroxypropane-1,2-diyl dipalmitoleate (564.48 Da) from a marine snail, Conus inscriptus, which binds to both CB1 and FAAH1 (glide energies: -70.61 and -30.52 kcal/mol, respectively). MD simulations indicate stable compound-target interaction for a minimum of 50 nanoseconds with relative invariabilities in Rg. The compound inhibited ovarian cancer cell line, PA1 at 1.7 µM. Structural and chemical interpretation of the compound (C2) was done using FT-IR, GC-MS, ESI-MS, 1H and 13C-NMR (1 and 2D). Furthermore, a probable route for gram-scale synthesis of C2 is hinted herein. With the available preliminary data, molecular mechanisms involving dual roles for this potent molecule must be elucidated to understand the possibilities of usage as an anticancer drug.

17.
Drug Metab Dispos ; 38(3): 459-73, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20016052

RESUMO

The pharmacokinetics and metabolism of anacetrapib (MK-0859), a novel cholesteryl ester transfer protein inhibitor, were examined in rats and rhesus monkeys. Anacetrapib exhibited a low clearance in both species and a moderate oral bioavailability of approximately 38% in rats and approximately 13% in monkeys. The area under the plasma concentration-time curve in both species increased in a less than dose-proportional manner over an oral dose range of 1 to 500 mg/kg. After oral administration of [(14)C]anacetrapib at 10 mg/kg, approximately 80 and 90% of the radioactive dose was recovered over 48 h postdose from rats and monkeys, respectively. The majority of the administered radioactive dose was excreted unchanged in feces in both species. Biliary excretion of radioactivity accounted for approximately 15% and urinary excretion for less than 2% of the dose. Thirteen metabolites, resulting from oxidative and secondary glucuronic acid conjugation, were identified in rat and monkey bile. The main metabolic pathways consisted of O-demethylation (M1) and hydroxylation on the biphenyl moiety (M2) and hydroxylation on the isopropyl side chain (M3); these hydroxylations were followed by O-glucuronidation of these metabolites. A glutathione adduct (M9), an olefin metabolite (M10), and a propionic acid metabolite (M11) also were identified. In addition to parent anacetrapib, M1, M2, and M3 metabolites were detected in rat but not in monkey plasma. Overall, it appears that anacetrapib exhibits a low-to-moderate degree of absorption after oral dosing and majority of the absorbed dose is eliminated via oxidation to a series of hydroxylated metabolites that undergo conjugation with glucuronic acid before excretion into bile.


Assuntos
Anticolesterolemiantes/farmacocinética , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Oxazolidinonas/farmacocinética , Animais , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/análise , Anticolesterolemiantes/química , Bile/química , Biotransformação , Análise Química do Sangue , Avaliação Pré-Clínica de Medicamentos , Fezes/química , Glucuronídeos/análise , Glucuronídeos/sangue , Glucuronídeos/química , Glucuronídeos/urina , Hidroxilação , Absorção Intestinal , Macaca mulatta , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Oxazolidinonas/administração & dosagem , Oxazolidinonas/análise , Oxazolidinonas/química , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Espectrometria de Massas em Tandem , Urina/química
18.
Drug Metab Dispos ; 38(1): 108-14, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19797605

RESUMO

MRL-1, a cannabinoid receptor-1 inverse agonist, was a member of a lead candidate series for the treatment of obesity. In rats, MRL-1 is eliminated mainly via metabolism, followed by excretion of the metabolites into bile. The major metabolite M1, a glutathione conjugate of MRL-1, was isolated and characterized by liquid chromatography/mass spectrometry and NMR spectroscopic methods. The data suggest that the t-butylsulfonyl group at C-2 of furopyridine was displaced by the glutathionyl group. In vitro experiments using rat and monkey liver microsomes in the presence of reduced glutathione (GSH) showed that the formation of M1 was independent of NADPH and molecular oxygen, suggesting that this reaction was not mediated by an oxidative reaction and a glutathione S-transferase (GST) was likely involved in catalyzing this reaction. Furthermore, a rat hepatic GST was capable of catalyzing the conversion of MRL-1 to M1 in the presence of GSH. When a close analog of MRL-1, a p-chlorobenzenesulfonyl furopyridine derivative (MRL-2), was incubated with rat liver microsomes in the presence of GSH, p-chlorobenzene sulfinic acid (M2) was also identified as a product in addition to the expected M1. Based on these data, a mechanism is proposed involving direct nucleophilic addition of GSH to sulfonylfuropyridine, resulting in an unstable adduct that spontaneously decomposes to form M1 and M2.


Assuntos
Biocatálise , Glutationa Transferase/metabolismo , Piridinas/farmacocinética , Compostos de Enxofre/farmacocinética , Animais , Bile/química , Biotransformação/fisiologia , Cromatografia Líquida , Citosol/metabolismo , Cães , Glutationa/metabolismo , Haplorrinos , Humanos , Fígado/enzimologia , Espectroscopia de Ressonância Magnética , Masculino , Microssomos Hepáticos/enzimologia , Estrutura Molecular , NADP/metabolismo , Piridinas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Especificidade da Espécie , Compostos de Enxofre/metabolismo , Espectrometria de Massas em Tandem
19.
Curr Cancer Drug Targets ; 19(6): 495-503, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30479215

RESUMO

BACKGROUND: The major attention has been received by the natural products in the prevention of diseases due to their pharmacological role. OBJECTIVE: The major focus of the study was to search for highly potential anti-cancer compounds from marine Streptomyces sp. VITJS4 (NCIM No. 5574). METHODS: Cytotoxic assay was examined by MTT assay on HepG2 cells. Bioassay-guided fractionation of the ethyl acetate extract from the fermented broth led to the isolation of the compound. The lead compound structure was elucidated by combined NMR and MS analysis, and the absolute configuration was assigned by extensive spectroscopic analysis. RESULTS: On the basis of spectroscopic data, the compound was identified as 1, 2 benzenedicarboxylic acid, mono 2-ethylhexyl (BMEH). The compound exhibited in vitro anticancer potential against liver (HepG2) cancer cells. Based on the flow cytometric analysis, it was evident that the BMEH was also effective in arresting the cell cycle at G1 phase. Further, the Western blotting analysis confirmed the down-regulation of Bcl-2 family proteins, and activation of caspase-9 and 3. The molecular docking and dynamics simulation were performed to reveal the activity of the compound over a time period of 10ns. From the molecular dynamics studies, it was found that the stability and compactness were attained by the protein by means of the compound interaction. CONCLUSION: This study highlights our collaborative efforts to ascertain lead molecules from marine actinomycete. This is the first and foremost report to prove the mechanistic studies of the purified compound 1, 2-benzene dicarboxylic acid, mono(2-ethylhexyl) ester isolated from marine Streptomyces sp.VITJS4 against HepG2 cells.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Antineoplásicos/farmacologia , Ácidos Ftálicos/farmacologia , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/metabolismo , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ácidos Ftálicos/química , Proteínas de Ligação a Poli-ADP-Ribose/química , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Domínios Proteicos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Streptomyces/química
20.
J Med Chem ; 51(7): 2108-14, 2008 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-18333607

RESUMO

X-ray crystallographic, NMR spectroscopic, and computational studies of taranabant afforded similar low-energy conformers with a significant degree of rigidity along the C11-N13-C14-C16-C17 backbone but with more flexibility around bonds C8-C11 and C8-O7. Mutagenesis and docking studies suggested that taranabant and rimonabant shared the same general binding area of CB1R but with significant differences in detailed interactions. Similar to rimonabant, taranabant interacted with a cluster of aromatic residues (F(3.36)200, W(5.43)279, W(6.48)356, and Y(5.39)275) through the two phenyl rings and with F(2.57)170 and L(7.42)387 through the CF 3-Pyr ring. The notable distinction between taranabant and rimonabant was that taranabant was hydrogen-bonded with S(7.39)383 but not with K(3.28)192, while rimonabant was hydrogen-bonded with K(3.28)192 but not with S(7.39)383. The strong hydrogen bonding between the amide NH of taranabant and hydroxyl of S(7.39)383 was key to the superior affinity of taranabant to CB1R.


Assuntos
Amidas/química , Amidas/farmacologia , Piridinas/química , Piridinas/farmacologia , Receptor CB1 de Canabinoide/agonistas , Sequência de Aminoácidos , Animais , Sítios de Ligação , Células CHO , Células Cultivadas , Simulação por Computador , Cricetinae , Cricetulus , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/normas , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Estrutura Molecular , Mutagênese Sítio-Dirigida , Receptor CB1 de Canabinoide/química , Receptor CB1 de Canabinoide/genética , Padrões de Referência , Alinhamento de Sequência , Relação Estrutura-Atividade
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