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1.
Annu Rev Pharmacol Toxicol ; 63: 341-358, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36100221

RESUMO

Arsenic is a naturally occurring hazardous element that is environmentally ubiquitous in various chemical forms. Upon exposure, the human body initiates an elimination pathway of progressive methylation into relatively less bioreactive and more easily excretable pentavalent methylated forms. Given its association with decreasing the internal burden of arsenic with ensuing attenuation of its related toxicities, biomethylation has been applauded for decades as a pure route of arsenic detoxification. However, the emergence of detectable trivalent species with profound toxicity has opened a long-standing debate regarding whether arsenic methylation is a detoxifying or bioactivating mechanism. In this review, we approach the topic of arsenic metabolism from both perspectives to create a complete picture of its potential role in the mitigation or aggravation of various arsenic-related pathologies.


Assuntos
Arsênio , Humanos , Arsênio/toxicidade , Metilação
2.
Immunity ; 47(1): 183-198.e6, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28723550

RESUMO

Tissue macrophages arise during embryogenesis from yolk-sac (YS) progenitors that give rise to primitive YS macrophages. Until recently, it has been impossible to isolate or derive sufficient numbers of YS-derived macrophages for further study, but data now suggest that induced pluripotent stem cells (iPSCs) can be driven to undergo a process reminiscent of YS-hematopoiesis in vitro. We asked whether iPSC-derived primitive macrophages (iMacs) can terminally differentiate into specialized macrophages with the help of growth factors and organ-specific cues. Co-culturing human or murine iMacs with iPSC-derived neurons promoted differentiation into microglia-like cells in vitro. Furthermore, murine iMacs differentiated in vivo into microglia after injection into the brain and into functional alveolar macrophages after engraftment in the lung. Finally, iPSCs from a patient with familial Mediterranean fever differentiated into iMacs with pro-inflammatory characteristics, mimicking the disease phenotype. Altogether, iMacs constitute a source of tissue-resident macrophage precursors that can be used for biological, pathophysiological, and therapeutic studies.


Assuntos
Técnicas de Cultura de Células/métodos , Hematopoese , Macrófagos/fisiologia , Neurônios/fisiologia , Células-Tronco Pluripotentes/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Embrião de Mamíferos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurogênese
3.
PLoS Genet ; 19(11): e1011043, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38033156

RESUMO

A prominent source of mutation in cancer is single-stranded DNA cytosine deamination by cellular APOBEC3 enzymes, which results in signature C-to-T and C-to-G mutations in TCA and TCT motifs. Although multiple enzymes have been implicated, reports conflict and it is unclear which protein(s) are responsible. Here we report the development of a selectable system to quantify genome mutation and demonstrate its utility by comparing the mutagenic activities of three leading candidates-APOBEC3A, APOBEC3B, and APOBEC3H. The human cell line, HAP1, is engineered to express the thymidine kinase (TK) gene of HSV-1, which confers sensitivity to ganciclovir. Expression of APOBEC3A and APOBEC3B, but not catalytic mutant controls or APOBEC3H, triggers increased frequencies of TK mutation and similar TC-biased cytosine mutation profiles in the selectable TK reporter gene. Whole genome sequences from independent clones enabled an analysis of thousands of single base substitution mutations and extraction of local sequence preferences with APOBEC3A preferring YTCW motifs 70% of the time and APOBEC3B 50% of the time (Y = C/T; W = A/T). Signature comparisons with breast tumor whole genome sequences indicate that most malignancies manifest intermediate percentages of APOBEC3 signature mutations in YTCW motifs, mostly between 50 and 70%, suggesting that both enzymes contribute in a combinatorial manner to the overall mutation landscape. Although the vast majority of APOBEC3A- and APOBEC3B-induced single base substitution mutations occur outside of predicted chromosomal DNA hairpin structures, whole genome sequence analyses and supporting biochemical studies also indicate that both enzymes are capable of deaminating the single-stranded loop regions of DNA hairpins at elevated rates. These studies combine to help resolve a long-standing etiologic debate on the source of APOBEC3 signature mutations in cancer and indicate that future diagnostic and therapeutic efforts should focus on both APOBEC3A and APOBEC3B.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Mutação , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Linhagem Celular , DNA/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Citosina/metabolismo
4.
N Engl J Med ; 386(21): 1998-2010, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35613022

RESUMO

BACKGROUND: Although hypomethylating agents are currently used to treat patients with cancer, whether they can also reactivate and up-regulate oncogenes is not well elucidated. METHODS: We examined the effect of hypomethylating agents on SALL4, a known oncogene that plays an important role in myelodysplastic syndrome and other cancers. Paired bone marrow samples that were obtained from two cohorts of patients with myelodysplastic syndrome before and after treatment with a hypomethylating agent were used to explore the relationships among changes in SALL4 expression, treatment response, and clinical outcome. Leukemic cell lines with low or undetectable SALL4 expression were used to study the relationship between SALL4 methylation and expression. A locus-specific demethylation technology, CRISPR-DNMT1-interacting RNA (CRISPR-DiR), was used to identify the CpG island that is critical for SALL4 expression. RESULTS: SALL4 up-regulation after treatment with hypomethylating agents was observed in 10 of 25 patients (40%) in cohort 1 and in 13 of 43 patients (30%) in cohort 2 and was associated with a worse outcome. Using CRISPR-DiR, we discovered that demethylation of a CpG island within the 5' untranslated region was critical for SALL4 expression. In cell lines and patients, we confirmed that treatment with a hypomethylating agent led to demethylation of the same CpG region and up-regulation of SALL4 expression. CONCLUSIONS: By combining analysis of patient samples with CRISPR-DiR technology, we found that demethylation and up-regulation of an oncogene after treatment with a hypomethylating agent can indeed occur and should be further studied. (Funded by Associazione Italiana per la Ricerca sul Cancro and others.).


Assuntos
Antineoplásicos , Desmetilação , Síndromes Mielodisplásicas , Oncogenes , Regulação para Cima , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Desmetilação/efeitos dos fármacos , Humanos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Oncogenes/efeitos dos fármacos , Oncogenes/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
5.
Exp Cell Res ; 441(1): 114150, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38971519

RESUMO

Despite significant advances in the treatment of colorectal cancer (CRC), identification of novel targets and treatment options are imperative for improving its prognosis and survival rates. The mitochondrial SIRT3 and SHMT2 have key roles in metabolic reprogramming and cell proliferation. This study investigated the potential use of the natural product apigenin in CRC treatment employing both in vivo and in vitro models and explored the role of SIRT3 and SHMT2 in apigenin-induced CRC apoptosis. The role of SHMT2 in CRC patients' survival was verified using TCGA database. In vivo, apigenin treatment restored the normal colon appearance. On the molecular level, apigenin augmented the immunohistochemical expression of cleaved caspase-3 and attenuated SIRT3 and SHMT2 mRNA expression CRC patients with decreased SHMT2 expression had improved overall and disease-free survival rates. In vitro, apigenin reduced the cell viability in a time-dependent manner, induced G0/G1 cell cycle arrest, and increased the apoptotic cell population compared to the untreated control. Mechanistically, apigenin treatment mitigated the expression of SHMT2, SIRT3, and its upstream long intergenic noncoding RNA LINC01234 in CRC cells. Conclusively, apigenin induces caspase-3-dependent apoptosis in CRC through modulation of SIRT3-triggered mitochondrial pathway suggesting it as a promising therapeutic agent to improve patient outcomes.


Assuntos
Apigenina , Apoptose , Proliferação de Células , Neoplasias Colorretais , Sirtuína 3 , Apigenina/farmacologia , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Sirtuína 3/metabolismo , Sirtuína 3/genética , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Animais , Camundongos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Glicina Hidroximetiltransferase
6.
Proc Natl Acad Sci U S A ; 119(43): e2203180119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36269860

RESUMO

The phosphoinositide 3-kinase (PI3K) pathway represents the most hyperactivated oncogenic pathway in triple-negative breast cancer (TNBC), a highly aggressive tumor subtype encompassing ∼15% of breast cancers and which possesses no targeted therapeutics. Despite critical contributions of its signaling arms to disease pathogenesis, PI3K pathway inhibitors have not achieved expected clinical responses in TNBC, owing largely to a still-incomplete understanding of the compensatory cascades that operate downstream of PI3K. Here, we investigated the contributions of long noncoding RNAs (lncRNAs) to PI3K activities in clinical and experimental TNBC and discovered a prominent role for LINC01133 as a PI3K-AKT signaling effector. We found that LINC01133 exerted protumorigenic roles in TNBC and that it governed a previously undescribed mTOR Complex 2 (mTORC2)-dependent pathway that activated AKT in a PI3K-independent manner. Mechanistically, LINC01133 induced the expression of the mTORC2 component PROTOR1/PRR5 by competitively coupling away its negative messenger RNA (mRNA) regulator, the heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1). PROTOR1/PRR5 in turn was sufficient and necessary for LINC01133-triggered functions, casting previously unappreciated roles for this Rictor-binding protein in cellular signaling and growth. Notably, LINC01133 antagonism undermined cellular growth, and we show that the LINC01133-PROTOR1/PRR5 pathway was tightly associated with TNBC poor patient survival. Altogether, our findings uncovered a lncRNA-driven signaling shunt that acts as a critical determinant of malignancy downstream of the PI3K pathway and as a potential RNA therapeutic target in clinical TNBC management.


Assuntos
RNA Longo não Codificante , Neoplasias de Mama Triplo Negativas , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proliferação de Células/genética , Inibidores de Fosfoinositídeo-3 Quinase , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , RNA Mensageiro , Ribonucleoproteínas Nucleares Heterogêneas , Linhagem Celular Tumoral
7.
J Neurochem ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898700

RESUMO

Studies of the pathophysiology of fragile X syndrome (FXS) have predominantly focused on synaptic and neuronal disruptions in the disease. However, emerging studies highlight the consistency of white matter abnormalities in the disorder. Recent investigations using animal models of FXS have suggested a role for the fragile X translational regulator 1 protein (FMRP) in the development and function of oligodendrocytes, the myelinating cells of the central nervous system. These studies are starting to uncover FMRP's involvement in the regulation of myelin-related genes, such as myelin basic protein, and its influence on the maturation and functionality of oligodendrocyte precursor cells and oligodendrocytes. Here, we consider evidence of white matter abnormalities in FXS, review our current understanding of FMRP's role in oligodendrocyte development and function, and highlight gaps in our knowledge of the pathogenic mechanisms that may contribute to white matter abnormalities in FXS. Addressing these gaps may help identify new therapeutic strategies aimed at enhancing outcomes for individuals affected by FXS.

8.
Emerg Infect Dis ; 30(4): 807-809, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437706

RESUMO

We describe a case of tinea genitalis in an immunocompetent woman in Pennsylvania, USA. Infection was caused by Trichophyton indotineae potentially acquired through sexual contact. The fungus was resistant to terbinafine (first-line antifungal) but improved with itraconazole. Clinicians should be aware of T. indotineae as a potential cause of antifungal-resistant genital lesions.


Assuntos
Antifúngicos , Trichophyton , Feminino , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica , Itraconazol/uso terapêutico , Testes de Sensibilidade Microbiana , Terbinafina/farmacologia , Terbinafina/uso terapêutico
9.
Gastroenterology ; 164(5): 828-840, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36702360

RESUMO

The central role of the gut microbiota in the regulation of health and disease has been convincingly demonstrated. Polymicrobial interkingdom interactions between bacterial (the bacteriome) and fungal (the mycobiome) communities of the gut have become a prominent focus for development of potential therapeutic approaches. In addition to polymicrobial interactions, the complex gut ecosystem also mediates interactions between the host and the microbiota. These interactions are complex and bidirectional; microbiota composition can be influenced by host immune response, disease-specific therapeutics, antimicrobial drugs, and overall ecosystems. However, the gut microbiota also influences host immune response to a drug or therapy by potentially transforming the drug's structure and altering bioavailability, activity, or toxicity. This is especially true in cases where the gut microbiota has produced a biofilm. The negative ramifications of biofilm formation include alteration of gut permeability, enhanced antimicrobial resistance, and alteration of host immune response effectiveness. Natural modulation of the gut microbiota, using probiotic and prebiotic approaches, may also be used to affect the host microbiome, a type of "natural" modulation of the host microbiota composition. In this review, we discuss potential bidirectional interactions between microbes and host, and we describe the changes in gut microbiota induced by probiotic and prebiotic approaches as well as their potential clinical consequences, including biofilm formation. We outline a systematic approach to designing probiotics capable of altering the host microbiota in disease states, using Crohn's disease as a model chronic disease. Understanding how the effective changes in the microbiome may enhance treatment efficacy may unlock the possibility of modulating the gut microbiome to improve treatment using a natural approach.


Assuntos
Doença de Crohn , Microbioma Gastrointestinal , Microbiota , Probióticos , Humanos , Doença de Crohn/tratamento farmacológico , Probióticos/uso terapêutico , Prebióticos
10.
Artigo em Inglês | MEDLINE | ID: mdl-38916819

RESUMO

PURPOSE: Macrophage migration inhibitory factor (MIF) is an integral cytokine for the modulation of both innate and adaptive immunity and is involved in the pathogenesis of various cancers. However, conflicting findings on the relationship between MIF polymorphisms and breast cancer (BC) have been reported in earlier research. We investigated the clinical value of serum MIF levels and the association between MIF rs1049829 and rs755622 variants with their serum levels and propensity to develop BC. METHODS: A total of 133 treatment-naïve Egyptian BC females and 126 apparently healthy controls were matriculated in this case-control study. The serum MIF protein levels were quantified by ELISA, whereas the genotyping was executed utilizing the TaqMan® allelic discrimination assay. RESULTS: A significant increase in the serum MIF level in BC cases was observed in comparison to control subjects (P < 0.0001), with a diagnostic potential to discriminate BC with 92.5% sensitivity and 73.7% specificity at a cut-off value > 9.47 ng/mL. Besides, a significant difference in serum MIF level was observed in BC cases with progesterone receptor (PR) negativity compared to those with PR positivity (P = 0.046). Moreover, a significant association was depicted between the rs1049829 variant of MIF gene and the protective effect against BC meanwhile the rs755622 variant demonstrated no significant link with BC risk. CONCLUSIONS: This study revealed that serum MIF levels may be regarded as a promising serum tumor marker for BC. Also, the rs1049829 variant of the MIF gene is considered a protective candidate against BC.

11.
J Comput Chem ; 45(10): 663-670, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38088485

RESUMO

The oxazaphosphorine cyclophosphamide (CP) is a DNA-alkylating agent commonly used in cancer chemotherapy. This anticancer agent is administered as a prodrug activated by a liver cytochrome P450-catalyzed 4-hydroxylation reaction that yields the active, cytotoxic metabolite. The primary metabolite, 4-hydroxycyclophosphamide, equilibrates with the ring-open aldophosphamide that undergoes ß-elimination to yield the therapeutically active DNA cross-linking phosphoramide mustard and the byproduct acrolein. The present paper presents a DFT investigation of the different metabolic phases and an insight into the mechanism by which CP exerts its cytotoxic action. A detailed computational analysis of the energy profiles describing all the involved transformations and the mechanism of DNA alkylation is given with the aim to contribute to an increase of knowledge that, after more than 60 years of unsuccessful attempts, can lead to the design and development of a new generation of oxazaphosphorines.


Assuntos
Acroleína , DNA , Ciclofosfamida/farmacologia , Hidroxilação
12.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34965583

RESUMO

Chromatin immunoprecipitation coupled with sequencing (ChIP-seq) is a technique used to identify protein-DNA interaction sites through antibody pull-down, sequencing and analysis; with enrichment 'peak' calling being the most critical analytical step. Benchmarking studies have consistently shown that peak callers have distinct selectivity and specificity characteristics that are not additive and seldom completely overlap in many scenarios, even after parameter optimization. We therefore developed ChIP-AP, an integrated ChIP-seq analysis pipeline utilizing four independent peak callers, which seamlessly processes raw sequencing files to final result. This approach enables (1) better gauging of peak confidence through detection by multiple algorithms, and (2) more thoroughly surveys the binding landscape by capturing peaks not detected by individual callers. Final analysis results are then integrated into a single output table, enabling users to explore their data by applying selectivity and sensitivity thresholds that best address their biological questions, without needing any additional reprocessing. ChIP-AP therefore presents investigators with a more comprehensive coverage of the binding landscape without requiring additional wet-lab observations.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência de DNA/métodos , Algoritmos , Benchmarking , Linhagem Celular , Imunoprecipitação da Cromatina , Software , Fatores de Transcrição
13.
BMC Microbiol ; 24(1): 184, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802754

RESUMO

BACKGROUND: Pseudomonas aeruginosa is an opportunistic pathogen responsible for complicated UTIs and exhibits high antibiotic resistance, leading to increased mortality rates, especially in cases of multidrug-resistant strains. This study aimed to investigate the antibiotic susceptibility patterns and genomic characterization of XDR strains identified in end-stage liver disease patients who underwent liver transplants. METHODS: In this study, a number of 30 individuals who underwent liver transplants were registered. Ninety urine and 60 wound site swab samples were collected and processed for culturing, identification, and antimicrobial sensitivity. Extensively drug-resistant strain EMARA01 was confirmed through Sanger sequencing and was then processed for whole genome sequencing to characterize the genomic pattern. Sequencing data were processed for de novo assembly using various tools and databases, including genome annotation, serotype identification, virulence factor genes, and antimicrobial resistance gene. Pangenome analysis of randomly selected 147 reference strains and EMAR01 sequenced strain was performed using the Bacterial Pan Genome Analysis (BPGA) software. RESULTS: Of these total examined samples, nosocomial infection due to P. aeruginosa was detected in twelve patients' samples. AST analysis showed that P. aeruginosa strains exhibit resistance to tobramycin, erythromycin, and gentamicin, followed by piperacillin and ofloxacin, and no strains exhibit resistance to meropenem and imipenem. The CARD database identified 59 AMR genes similar to the EMAR01 strain genome and mostly belong to the family involved in the resistance-nodulation-cell division (RND) antibiotic efflux pump. Five genes; nalC, nalD, MexR, MexA, and MexB, exhibit resistance to 14 classes of antibiotics, while two AMR; CpxR, and OprM, exhibit resistance to 15 classes of drugs. Pangenome analysis revealed that the pan-genome remained open, suggesting the potential for acquiring accessory and unique genes. Notably, the genes predominantly involved in amino acid transport metabolism were identified using the KEGG database. CONCLUSIONS: This study provides valuable insights into the antimicrobial resistance profile, genetic features, and genomic evolution of P. aeruginosa strains causing UTIs in liver transplant patients. The findings emphasize the significance of comprehending AMR mechanisms and genetic diversity in P. aeruginosa for developing effective treatment strategies and infection control measures.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana Múltipla , Transplante de Fígado , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas , Pseudomonas aeruginosa , Infecções Urinárias , Sequenciamento Completo do Genoma , Humanos , Farmacorresistência Bacteriana Múltipla/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Transplante de Fígado/efeitos adversos , Egito , Infecções Urinárias/microbiologia , Infecções por Pseudomonas/microbiologia , Antibacterianos/farmacologia , Masculino , Feminino , Genoma Bacteriano/genética , Adulto , Infecção Hospitalar/microbiologia , Pessoa de Meia-Idade , Fatores de Virulência/genética
14.
J Recept Signal Transduct Res ; : 1-13, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189140

RESUMO

Hsp27 is a member of the small heat-shock proteins (sHSPs) - the known cellular line of defence against abnormal protein folding behaviors. Nevertheless, its upregulation is linked to a variety of pathological disorders, including several types of cancers. The ceramide synthases (CerS) mediate the synthesis of ceramide, a critical structural and signaling lipid. Functionally, downstream ceramide metabolites are implicated in the apoptosis process and their abnormal functionality has been linked to anticancer resistance. Studies showed that CerS1 are possibly inhibited by Hsp27 leading to biochemical anticancer effects in vitro. Nevertheless, the nature of such protein-protein interaction (PPI) has not been considerably investigated in molecular terms, hence, we present the first description of the dynamics CerS1-Hsp27 interaction landscapes using molecular dynamics simulations. Time-scale molecular dynamics simulation analysis indicated a system-wide conformational events of decreased stability, increased flexibility, reduced compactness, and decreased folding of CerS1. Analysis of binding energy showed a favorable interaction entailing 56 residues at the interface and a total stabilizing energy of -158 KJ/mol. The CerS1 catalytic domain experienced an opposite trend compared to the protein backbone. Yet, these residues adopted a highly compact conformation as per DCCM and DSSP analysis. Furthermore, conserved residues (SER 212, ASP 213, ALA 240, GLY 243, ASP 319) comprising the substrate shuttling machinery showed notable rigidity implying a restrained ceramide precursor access and assembly; hence, a possible inhibitory mechanism. Findings from this report would streamline a better molecular understanding of CerS1-Hsp27 interactions and decipher its potential avenue toward unexplored anti-cancer mechanisms and therapy.

15.
Arch Biochem Biophys ; 754: 109958, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38499054

RESUMO

The aryl hydrocarbon receptor (AhR) functions as a vital ligand-activated transcription factor, governing both physiological and pathophysiological processes. Notably, it responds to xenobiotics, leading to a diverse array of outcomes. In the context of drug repurposing, we present here a combined approach of utilizing structure-based virtual screening and molecular dynamics simulations. This approach aims to identify potential AhR modulators from Drugbank repository of clinically approved drugs. By focusing on the AhR PAS-B binding pocket, our screening protocol included binding affinities calculations, complex stability, and interactions within the binding site as a filtering method. Comprehensive evaluations of all DrugBank small molecule database revealed ten promising hits. This included flibanserin, butoconazole, luliconazole, naftifine, triclabendazole, rosiglitazone, empagliflozin, benperidol, nebivolol, and zucapsaicin. Each exhibiting diverse binding behaviors and remarkably very low binding free energy. Experimental studies further illuminated their modulation of AhR signaling, and showing that they are consistently reducing AhR activity, except for luliconazole, which intriguingly enhances the AhR activity. This work demonstrates the possibility of using computational modelling as a quick screening tool to predict new AhR modulators from extensive drug libraries. Importantly, these findings hold immense therapeutic potential for addressing AhR-associated disorders. Consequently, it offers compelling prospects for innovative interventions through drug repurposing.


Assuntos
Receptores de Hidrocarboneto Arílico , Receptores de Hidrocarboneto Arílico/metabolismo , Sítios de Ligação , Ligação Proteica , Domínios Proteicos , Ligantes
16.
Arch Biochem Biophys ; 759: 110088, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992456

RESUMO

Ponatinib and tofacitinib, established kinase inhibitors and FDA-approved for chronic myeloid leukemia and rheumatoid arthritis, are recently undergoing investigation in diverse clinical trials for potential repurposing. The aryl hydrocarbon receptor (AhR), a transcription factor influencing a spectrum of physiological and pathophysiological activities, stands as a therapeutic target for numerous diseases. This study employs molecular modelling tools and in vitro assays to identify ponatinib and tofacitinib as AhR ligands, elucidating their binding and molecular interactions in the AhR PAS-B domain. Molecular docking analyses revealed that ponatinib and tofacitinib occupy the central pocket within the primary cavity, similar to AhR agonists 2,3,7,8-tetrachlorodibenzodioxin (TCDD) and (benzo[a]pyrene) B[a]P. Our simulations also showed that these compounds exhibit good stability, stabilizing many hot spots within the PAS-B domain, including the Dα-Eα loop, which serves as a regulatory element for the binding pocket. Binding energy calculations highlighted ponatinib's superior predicted affinity, revealing F295 as a crucial residue in maintaining strong interaction with the two compounds. Our in vitro data suggest that ponatinib functions as an AhR antagonist, blocking the downstream signaling of AhR pathway induced by TCDD and B[a]P. Additionally, both tofacitinib and ponatinib cause impairment in AhR-regulated CYP1A1 enzyme activity induced by potent AhR agonists. This study unveils ponatinib and tofacitinib as potential modulators of AhR, providing valuable insights into their therapeutic roles in AhR-associated diseases and enhancing our understanding of the intricate relationship between kinase inhibitors and AhR.


Assuntos
Imidazóis , Piperidinas , Piridazinas , Pirimidinas , Receptores de Hidrocarboneto Arílico , Humanos , Sítios de Ligação , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A1/antagonistas & inibidores , Imidazóis/farmacologia , Imidazóis/química , Ligantes , Simulação de Acoplamento Molecular , Piperidinas/farmacologia , Piperidinas/química , Ligação Proteica , Piridazinas/farmacologia , Piridazinas/química , Pirimidinas/farmacologia , Pirimidinas/química , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/química , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , /farmacologia
17.
Curr Atheroscler Rep ; 26(8): 395-410, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38869707

RESUMO

PURPOSE OF REVIEW: To eradicate atherosclerotic diseases, novel biomarkers, and future therapy targets must reveal the burden of early atherosclerosis (AS), which occurs before life-threatening unstable plaques form. The chemical and biological features of microRNAs (miRNAs) make them interesting biomarkers for numerous diseases. We summarized the latest research on miRNA regulatory mechanisms in AS progression studies, which may help us use miRNAs as biomarkers and treatments for difficult-to-treat diseases. RECENT FINDINGS: Recent research has demonstrated that miRNAs have a regulatory function in the observed changes in gene and protein expression during atherogenesis, the process that leads to atherosclerosis. Several miRNAs play a role in the development of atherosclerosis, and these miRNAs could potentially serve as non-invasive biomarkers for atherosclerosis in various regions of the body. These miRNAs have the potential to serve as biomarkers and targets for early treatment of atherosclerosis. The start and development of AS require different miRNAs. It reviews new research on miRNAs affecting endothelium, vascular smooth muscle, vascular inflammation, lipid retention, and cholesterol metabolism in AS. A miRNA gene expression profile circulates with AS everywhere. AS therapies include lipid metabolism, inflammation reduction, and oxidative stress inhibition. Clinical use of miRNAs requires tremendous progress. We think tiny miRNAs can enable personalized treatment.


Assuntos
Aterosclerose , Biomarcadores , MicroRNAs , Humanos , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/diagnóstico , Aterosclerose/terapia , MicroRNAs/genética , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Prognóstico , Animais
19.
Arch Microbiol ; 206(3): 124, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38409503

RESUMO

Quorum sensing (QS) is a communication mechanism employed by many bacteria to regulate gene expression in a population density-dependent manner. It plays a crucial role in coordinating various bacterial behaviors, including biofilm formation, virulence factor production, and antibiotic resistance. However, the dysregulation of QS can lead to detrimental effects, making it an attractive target for developing novel therapeutic strategies. Anti-QS approaches aim to interfere with QS signaling pathways, inhibiting the communication between bacteria, and disrupting their coordinated activities. Various strategies have been explored to achieve this goal. Advances in understanding QS mechanisms and the discovery of new targets have paved the way for the development of innovative anti-QS approaches. Combining multiple anti-QS strategies or utilizing them in combination with traditional antibiotics holds great promise for combating bacterial infections and addressing the challenges posed by antibiotic resistance. Anti-QS approaches offer a diverse range of strategies including natural compounds, antibody-mediated quorum quenching (QQ), computer-aided drug design for QQ, repurposing of Drugs approved by FDA as anti-QS agents and modulating quorum-sensing molecules which were discussed in detail in this review. This review, comprehensively and for the first time, sheds light on the significance of diverse anti-QS strategies in solving antimicrobial resistance problem in Gram-negative microbial infection.


Assuntos
Infecções Bacterianas , Percepção de Quorum , Humanos , Bactérias/metabolismo , Infecções Bacterianas/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/metabolismo , Bactérias Gram-Negativas , Controle de Infecções , Biofilmes
20.
Arch Microbiol ; 206(3): 101, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353831

RESUMO

A biofilm is a collection of microorganisms organized in a matrix of extracellular polymeric material. Biofilms consist of microbial cells that attach to both surfaces and each other, whether they are living or non-living. These microbial biofilms can lead to hospital-acquired infections and are generally detrimental. They possess the ability to resist the human immune system and antibiotics. The National Institute of Health (NIH) states that biofilm formation is associated with 65% of all microbial illnesses and 80% of chronic illnesses. Additionally, non-device-related microbial biofilm infections include conditions like cystic fibrosis, otitis media, infective endocarditis, and chronic inflammatory disorders. This review aims to provide an overview of research on chronic infections caused by microbial biofilms, methods used for biofilm detection, recent approaches to combat biofilms, and future perspectives, including the development of innovative antimicrobial strategies such as antimicrobial peptides, bacteriophages, and agents that disrupt biofilms.


Assuntos
Bacteriófagos , Infecção Hospitalar , Fibrose Cística , Humanos , Antibacterianos/farmacologia , Biofilmes
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