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1.
Cell Mol Life Sci ; 81(1): 141, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485766

RESUMO

Human papillomavirus (HPV) infection is a primary cause of cervical and head-and-neck cancers. The HPV genome enters the nucleus during mitosis when the nuclear envelope disassembles. Given that lamins maintain nuclear integrity during interphase, we asked to what extent their loss would affect early HPV infection. To address this question, we infected human cervical cancer cells and keratinocytes lacking the major lamins with a HPV16 pseudovirus (HP-PsV) encoding an EGFP reporter. We found that a sustained reduction or complete loss of lamin B1 significantly increased HP-PsV infection rate. A corresponding greater nuclear HP-PsV load in LMNB1 knockout cells was directly related to their prolonged mitotic window and extensive nuclear rupture propensity. Despite the increased HP-PsV presence, EGFP transcript levels remained virtually unchanged, indicating an additional defect in protein turnover. Further investigation revealed that LMNB1 knockout led to a substantial decrease in autophagic capacity, possibly linked to the persistent activation of cGAS by cytoplasmic chromatin exposure. Thus, the attrition of lamin B1 increases nuclear perviousness and attenuates autophagic capacity, creating an environment conducive to unrestrained accumulation of HPV capsids. Our identification of lower lamin B1 levels and nuclear BAF foci in the basal epithelial layer of several human cervix samples suggests that this pathway may contribute to an increased individual susceptibility to HPV infection.


Assuntos
Lamina Tipo B , Infecções por Papillomavirus , Feminino , Humanos , Lamina Tipo B/genética , Lamina Tipo B/metabolismo , Infecções por Papillomavirus/genética , Membrana Nuclear/metabolismo , Mitose , Cromossomos/metabolismo , Lamina Tipo A/genética , Lamina Tipo A/metabolismo
2.
EMBO Rep ; 23(1): e53083, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34699114

RESUMO

Here, we investigate the impact of hypoxia on the hepatic response of glucocorticoid receptor (GR) to dexamethasone (DEX) in mice via RNA-sequencing. Hypoxia causes three types of reprogramming of GR: (i) much weaker induction of classical GR-responsive genes by DEX in hypoxia, (ii) a number of genes is induced by DEX specifically in hypoxia, and (iii) hypoxia induces a group of genes via activation of the hypothalamic-pituitary-adrenal (HPA) axis. Transcriptional profiles are reflected by changed GR DNA-binding as measured by ChIP sequencing. The HPA axis is induced by hypothalamic HIF1α and HIF2α activation and leads to GR-dependent lipolysis and ketogenesis. Acute inflammation, induced by lipopolysaccharide, is prevented by DEX in normoxia but not during hypoxia, and this is attributed to HPA axis activation by hypoxia. We unfold new physiological pathways that have consequences for patients suffering from GC resistance.


Assuntos
Glucocorticoides , Receptores de Glucocorticoides , Animais , Dexametasona/metabolismo , Dexametasona/farmacologia , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Hipóxia/genética , Hipóxia/metabolismo , Camundongos , Sistema Hipófise-Suprarrenal/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo
3.
Euro Surveill ; 29(7)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38362626

RESUMO

BackgroundAntimicrobial resistance (AMR) of Mycoplasma genitalium (MG) is a growing concern worldwide and surveillance is needed. In Belgium, samples are sent to the National Reference Centre of Sexually Transmitted Infections (NRC-STI) on a voluntary basis and representative or robust national AMR data are lacking.AimWe aimed to estimate the occurrence of resistant MG in Belgium.MethodsBetween July and November 2022, frozen remnants of MG-positive samples from 21 Belgian laboratories were analysed at the NRC-STI. Macrolide and fluoroquinolone resistance-associated mutations (RAMs) were assessed using Sanger sequencing of the 23SrRNA and parC gene. Differences in resistance patterns were correlated with surveillance methodology, socio-demographic and behavioural variables via Fisher's exact test and logistic regression analysis.ResultsOf the 244 MG-positive samples received, 232 could be sequenced for macrolide and fluoroquinolone RAMs. Over half of the sequenced samples (55.2%) were resistant to macrolides. All sequenced samples from men who have sex with men (MSM) (24/24) were macrolide-resistant. Fluoroquinolone RAMs were found in 25.9% of the samples and occurrence did not differ between socio-demographic and sexual behaviour characteristics.ConclusionAlthough limited in sample size, our data suggest no additional benefit of testing MG retrieved from MSM for macrolide resistance in Belgium, when making treatment decisions. The lower occurrence of macrolide resistance in other population groups, combined with emergence of fluoroquinolone RAMs support macrolide-resistance testing in these groups. Continued surveillance of resistance in MG in different population groups will be crucial to confirm our findings and to guide national testing and treatment strategies.


Assuntos
Infecções por Mycoplasma , Mycoplasma genitalium , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Masculino , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Homossexualidade Masculina , Mycoplasma genitalium/genética , Bélgica/epidemiologia , Macrolídeos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/epidemiologia , Mutação , RNA Ribossômico 23S/genética , Fluoroquinolonas/farmacologia
4.
Mol Ecol ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37933429

RESUMO

A species' success during the invasion of new areas hinges on an interplay between the demographic processes common to invasions and the specific ecological context of the novel environment. Evolutionary genetic studies of invasive species can investigate how genetic bottlenecks and ecological conditions shape genetic variation in invasions, and our study pairs two invasive populations that are hypothesized to be from the same source population to compare how each population evolved during and after introduction. Invasive European starlings (Sturnus vulgaris) established populations in both Australia and North America in the 19th century. Here, we compare whole-genome sequences among native and independently introduced European starling populations to determine how demographic processes interact with rapid evolution to generate similar genetic patterns in these recent and replicated invasions. Demographic models indicate that both invasive populations experienced genetic bottlenecks as expected based on invasion history, and we find that specific genomic regions have differentiated even on this short evolutionary timescale. Despite genetic bottlenecks, we suggest that genetic drift alone cannot explain differentiation in at least two of these regions. The demographic boom intrinsic to many invasions as well as potential inversions may have led to high population-specific differentiation, although the patterns of genetic variation are also consistent with the hypothesis that this infamous and highly mobile invader adapted to novel selection (e.g., extrinsic factors). We use targeted sampling of replicated invasions to identify and evaluate support for multiple, interacting evolutionary mechanisms that lead to differentiation during the invasion process.

5.
Sex Transm Infect ; 99(5): 330-336, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36396173

RESUMO

OBJECTIVE: The available epidemiological and clinical evidence from the currently ongoing monkeypox (MPX) outbreak in non-endemic areas suggests an important factor of sexual transmission. However, limited information on the behaviour and experiences of individuals with an MPX infection has to date been provided. We aimed to describe the initial phase of the MPX outbreak in Belgium, and to provide a more in-depth description of sexual behaviour and transmission contexts. METHODS: We used routine national surveillance data of 139 confirmed MPX cases with date of symptom onset until 19 June 2022, complemented with 12 semistructured interviews conducted with a subsample of these cases. RESULTS: Sexualised environments, including large festivals and cruising venues for gay men, were the suspected exposure setting for the majority of the cases in the early outbreak phase. In-depth narratives of sexual behaviour support the hypothesis of MPX transmission through close physical contact during sex. Despite awareness of the ongoing MPX outbreak, low self-perceived risk of MPX acquisition and confusing initial signs and symptoms for other STIs or skin conditions delayed early detection of an MPX infection. In addition, we describe relevant contextual factors beyond individual behaviour, related to sexual networks, interpersonal interactions and health systems. Some of these factors may complicate early MPX detection and control efforts. CONCLUSION: Our results highlight the role of sexual contact and networks in the transmission of MPX during the early phase of the outbreak in Belgium. Risk communication messages should consistently and transparently state the predominant sexual transmission potential of MPX virus, and prevention and control measures must be adapted to reflect multilevel factors contributing to MPX transmission risk.


Assuntos
Surtos de Doenças , Monkeypox virus , Masculino , Humanos , Bélgica/epidemiologia , Comportamento Sexual , Comunicação
6.
Euro Surveill ; 28(27)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37410383

RESUMO

BackgroundSince May 2022, an mpox outbreak affecting primarily men who have sex with men (MSM) has occurred in numerous non-endemic countries worldwide. As MSM frequently reported multiple sexual encounters in this outbreak, reliably determining the time of infection is difficult; consequently, estimation of the incubation period is challenging.AimWe aimed to provide valid and precise estimates of the incubation period distribution of mpox by using cases associated with early outbreak settings where infection likely occurred.MethodsColleagues in European countries were invited to provide information on exposure intervals and date of symptom onset for mpox cases who attended a fetish festival in Antwerp, Belgium, a gay pride festival in Gran Canaria, Spain or a particular club in Berlin, Germany, where early mpox outbreaks occurred. Cases of these outbreaks were pooled; doubly censored models using the log-normal, Weibull and Gamma distributions were fitted to estimate the incubation period distribution.ResultsWe included data on 122 laboratory-confirmed cases from 10 European countries. Depending on the distribution used, the median incubation period ranged between 8 and 9 days, with 5th and 95th percentiles ranging from 2 to 3 and from 20 to 23 days, respectively. The shortest interval that included 50% of incubation periods spanned 8 days (4-11 days).ConclusionCurrent public health management of close contacts should consider that in approximately 5% of cases, the incubation period exceeds the commonly used monitoring period of 21 days.


Assuntos
Homossexualidade Masculina , Mpox , Humanos , Masculino , Berlim/epidemiologia , Surtos de Doenças , Férias e Feriados , Período de Incubação de Doenças Infecciosas , Mpox/epidemiologia , Minorias Sexuais e de Gênero
7.
Int J Mol Sci ; 24(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38003603

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by a constant accumulation of lipids in the liver. This hepatic lipotoxicity is associated with a dysregulation of the first step in lipid catabolism, known as beta oxidation, which occurs in the mitochondrial matrix. Eventually, this dysregulation will lead to mitochondrial dysfunction. To evaluate the possible involvement of mitochondrial DNA methylation in this lipid metabolic dysfunction, we investigated the functional metabolic effects of mitochondrial overexpression of CpG (MSssI) and GpC (MCviPI) DNA methyltransferases in relation to gene expression and (mito)epigenetic signatures. Overall, the results show that mitochondrial GpC and, to a lesser extent, CpG methylation increase bile acid metabolic gene expression, inducing the onset of cholestasis through mito-nuclear epigenetic reprogramming. Moreover, both increase the expression of metabolic nuclear receptors and thereby induce basal overactivation of mitochondrial respiration. The latter promotes mitochondrial swelling, favoring lipid accumulation and metabolic-stress-induced mitophagy and autophagy stress responses. In conclusion, both mitochondrial GpC and CpG methylation create a metabolically challenging environment that induces mitochondrial dysfunction, which may contribute to the progression of MASLD.


Assuntos
Fígado Gorduroso , Mitofagia , Humanos , Mitofagia/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , DNA Mitocondrial/metabolismo , Fígado Gorduroso/metabolismo , Estresse Fisiológico , Lipídeos
8.
J Biol Chem ; 297(6): 101377, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34742736

RESUMO

The steroidal lactone withaferin A (WFA) is a dietary phytochemical, derived from Withania somnifera. It exhibits a wide range of biological properties, including immunomodulatory, anti-inflammatory, antistress, and anticancer activities. Here we investigated the effect of WFA on T-cell motility, which is crucial for adaptive immune responses as well as autoimmune reactions. We found that WFA dose-dependently (within the concentration range of 0.3-1.25 µM) inhibited the ability of human T-cells to migrate via cross-linking of the lymphocyte function-associated antigen-1 (LFA-1) integrin with its ligand, intercellular adhesion molecule 1 (ICAM-1). Coimmunoprecipitation of WFA interacting proteins and subsequent tandem mass spectrometry identified a WFA-interactome consisting of 273 proteins in motile T-cells. In particular, our data revealed significant enrichment of the zeta-chain-associated protein kinase 70 (ZAP70) and cytoskeletal actin protein interaction networks upon stimulation. Phospho-peptide mapping and kinome analysis substantiated kinase signaling downstream of ZAP70 as a key WFA target, which was further confirmed by bait-pulldown and Western immunoblotting assays. The WFA-ZAP70 interaction was disrupted by a disulfide reducing agent dithiothreitol, suggesting an involvement of cysteine covalent binding interface. In silico docking predicted WFA binding to ZAP70 at cystine 560 and 564 residues. These findings provide a mechanistic insight whereby WFA binds to and inhibits the ZAP70 kinase and impedes T-cell motility. We therefore conclude that WFA may be exploited to pharmacologically control host immune responses and potentially prevent autoimmune-mediated pathologies.


Assuntos
Movimento Celular/efeitos dos fármacos , Proteínas Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Vitanolídeos/farmacologia , Proteína-Tirosina Quinase ZAP-70/antagonistas & inibidores , Células Cultivadas , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Antígeno-1 Associado à Função Linfocitária/metabolismo , Fosforilação , Linfócitos T/citologia , Linfócitos T/enzimologia
9.
Sex Transm Infect ; 97(4): 297-303, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32769204

RESUMO

OBJECTIVES: The number of reported cases of multiresistant Mycoplasma genitalium (MG) is increasing globally. The aim of this study was to estimate the prevalence of macrolide and possible fluoroquinolone resistance-associated mutations (RAMs) of MG in Belgium. METHODS: The study was performed retrospectively on two sets of MG-positive samples collected in Belgium between 2015 and 2018. The first set of samples originated from routine surveillance activities and the second set came from a cohort of men who have sex with men (MSM) using pre-exposure prophylaxis to prevent HIV transmission. Detection of RAMs to macrolides and fluoroquinolones was performed on all samples using DNA sequencing of the 23S ribosomal RNA gene, the gyrA gene and the parC gene. RESULTS: Seventy-one per cent of the MG samples contained a mutation conferring resistance to macrolides or fluoroquinolones (ParC position 83/87). RAMs were more frequently found among men compared with women for fluoroquinolones (23.9% vs 9.1%) and macrolides (78.4% vs 27.3%). Almost 90% of the MG infections among MSM possessed a RAM to macrolides (88.4%). In addition, 18.0% of the samples harboured both macrolides and fluoroquinolone RAMs; 3.0% in women and 24.2% in MSM. Being MSM was associated with macrolide RAMs (OR 15.3), fluoroquinolone RAMs (OR 3.8) and having a possible multiresistant MG infection (OR 7.2). CONCLUSION: The study shows an alarmingly high prevalence of MG with RAMs to macrolides and fluoroquinolones in Belgium. These results highlight the need to improve antimicrobial stewardship in Belgium in order to avoid the emergence of untreatable MG.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Macrolídeos/farmacologia , Mutação , Infecções por Mycoplasma/genética , Mycoplasma genitalium/genética , Adulto , Bélgica/epidemiologia , DNA Girase/análise , DNA Topoisomerase IV/análise , DNA Bacteriano/química , Feminino , Humanos , Masculino , Prevalência , RNA Ribossômico 23S/análise , Estudos Retrospectivos , Análise de Sequência de DNA
10.
FASEB J ; 34(4): 4997-5015, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32052887

RESUMO

Development of the songbird brain provides an excellent experimental model for understanding the regulation of sex differences in ontogeny. Considering the regulatory role of the hypothalamus in endocrine, in particular reproductive, physiology, we measured the structural (volume) and molecular correlates of hypothalamic development during ontogeny of male and female zebra finches. We quantified by relative quantitative polymerase chain reaction (rqPCR) the expression of 14 genes related to thyroid and steroid hormones actions as well as 12 genes related to brain plasticity at four specific time points during ontogeny and compared these expression patterns with the expression of the same genes as detected by transcriptomics in the telencephalon. These two different methodological approaches detected specific changes with age and demonstrated that in a substantial number of cases changes observed in both brain regions are nearly identical. Other genes however had a tissue-specific developmental pattern. Sex differences or interactions of sex by age were detected in the expression of a subset of genes, more in hypothalamus than telencephalon. These results correlate with multiple known aspects of the developmental and reproductive physiology but also raise a number of new functional questions.


Assuntos
Hipotálamo/metabolismo , Desenvolvimento Sexual , Telencéfalo/metabolismo , Transcriptoma , Animais , Feminino , Tentilhões , Regulação da Expressão Gênica no Desenvolvimento , Hipotálamo/crescimento & desenvolvimento , Masculino , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Caracteres Sexuais , Telencéfalo/crescimento & desenvolvimento
11.
BMC Infect Dis ; 21(1): 947, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521367

RESUMO

BACKGROUND: Chlamydia trachomatis (chlamydia) is the most diagnosed sexually transmitted infection in Belgium. Screening programs focus on young women, due to the implications of chronic asymptomatic infections for reproductive health. Thereby, the frequency of infections in men and older adults is underestimated. This study aimed to estimate the point-prevalence of chlamydia in the broader Belgian population, to inform evidence-based prevention and control strategies. METHODS: We conducted two cross-sectional prevalence studies of chlamydia infection in the population of Belgium aged 16-59 years, 2018-2020. In the CT1 study 12,000 representative individuals were randomly selected from the national register and invited by letter to collect a urine sample at home. The CT2 study used urine samples collected through the Belgian Health Examination Survey. Molecular detection of chlamydia DNA was performed using Xpert® or Abbott Real-Time CT/NG assays. Weighted estimated prevalence and 95% confidence interval (CI) was calculated per gender and age groups of 16/18-29, 30-44 and 45-59 years, relative to the general Belgian population. Data collected on sociodemographic variables and sexual behavior were used to identify potential risk factors for chlamydia infection through calculation of the odds ratio (OR). RESULTS: The population-wide weighted estimated prevalence was 1.54% (95% CI 0.78-3) in CT1 and 1.76% (95% CI 0.63-4) in CT2. We observed no statistically significant difference between men and women or age groups. Civil relationship status (OR = 14.1 (95% CI 1.78-112), p < 0.01), sexual intercourse with a casual partner (OR = 6.31 (95% CI 1.66-24.1), p < 0.01) and > 3 sexual partners in the last 12 months (OR = 4.53 (95% CI 1.10-18.6), p = 0.02) were associated with higher relative risk for chlamydia infection. CONCLUSION: Nationwide prevalence studies are relevant to assess the distribution of chlamydia and inform public health actions. The overall low prevalence and heterogeneous distribution of chlamydia in the general Belgian population needs to be considered for future strategies and potential harm of testing and treating asymptomatic individuals need to be taken into account. Effective case management should include appropriate treatment of symptomatic patients and partner notification, and prevention strategies should encourage behaviors such as condom use.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Adolescente , Adulto , Bélgica/epidemiologia , Infecções por Chlamydia/epidemiologia , Estudos Transversais , Feminino , Genitália , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Comportamento Sexual , Adulto Jovem
12.
Mar Drugs ; 19(2)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499163

RESUMO

Marine plants have become an inexhaustible reservoir of new phytopharmaceuticals for cancer treatment. We demonstrate in vitro/in vivo antitumor efficacy of a standardized polyphenol extract from the marine angiosperm Thalassia testudinum (TTE) in colon tumor cell lines (RKO, SW480, and CT26) and a syngeneic allograft murine colorectal cancer model. MTT assays revealed a dose-dependent decrease of cell viability of RKO, CT26, and SW480 cells upon TTE treatment with IC50 values of, respectively, 175, 115, and 60 µg/mL. Furthermore, TTE significantly prevented basal and bFGF-induced angiogenesis in the chicken chorioallantoic membrane angiogenesis assay. In addition, TTE suppressed bFGF-induced migration of endothelial cells in a wound closure assay. Finally, TTE treatment abrogated CT26 colorectal cancer growth and increased overall organism survival in a syngeneic murine allograft model. Corresponding transcriptome profiling and pathway analysis allowed for the identification of the mechanism of action for the antitumor effects of TTE. In line with our in vitro/in vivo results, TTE treatment triggers ATF4-P53-NFκB specific gene expression and autophagy stress pathways. This results in suppression of colon cancer cell growth, cell motility, and angiogenesis pathways in vitro and in addition promotes antitumor immunogenic cell death in vivo.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Hydrocharitaceae , Morte Celular Imunogênica/efeitos dos fármacos , Neovascularização Patológica/patologia , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Humanos , Hydrocharitaceae/química , Morte Celular Imunogênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
13.
Int J Mol Sci ; 22(23)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34884535

RESUMO

Through phosphorylation of their substrate proteins, protein kinases are crucial for transducing cellular signals and orchestrating biological processes, including cell death and survival. Recent studies have revealed that kinases are involved in ferroptosis, an iron-dependent mode of cell death associated with toxic lipid peroxidation. Given that ferroptosis is being explored as an alternative strategy to eliminate apoptosis-resistant tumor cells, further characterization of ferroptosis-dependent kinase changes might aid in identifying novel druggable targets for protein kinase inhibitors in the context of cancer treatment. To this end, we performed a phosphopeptidome based kinase activity profiling of glucocorticoid-resistant multiple myeloma cells treated with either the apoptosis inducer staurosporine (STS) or ferroptosis inducer RSL3 and compared their kinome activity signatures. Our data demonstrate that both cell death mechanisms inhibit the activity of kinases classified into the CMGC and AGC families, with STS showing a broader spectrum of serine/threonine kinase inhibition. In contrast, RSL3 targets a significant number of tyrosine kinases, including key players of the B-cell receptor signaling pathway. Remarkably, additional kinase profiling of the anti-cancer agent withaferin A revealed considerable overlap with ferroptosis and apoptosis kinome activity, explaining why withaferin A can induce mixed ferroptotic and apoptotic cell death features. Altogether, we show that apoptotic and ferroptotic cell death induce different kinase signaling changes and that kinome profiling might become a valid approach to identify cell death chemosensitization modalities of novel anti-cancer agents.


Assuntos
Apoptose , Carbolinas/farmacologia , Ferroptose , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mieloma Múltiplo/patologia , Fosfoproteínas/metabolismo , Proteínas Quinases/metabolismo , Estaurosporina/farmacologia , Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Fosfoproteínas/genética , Fosforilação , Prognóstico , Proteínas Quinases/genética , Transcriptoma
14.
Int J Mol Sci ; 22(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34830117

RESUMO

Disease relapse and therapy resistance remain key challenges in treating multiple myeloma. Underlying (epi-)mutational events can promote myelomagenesis and contribute to multi-drug and apoptosis resistance. Therefore, compounds inducing ferroptosis, a form of iron and lipid peroxidation-regulated cell death, are appealing alternative treatment strategies for multiple myeloma and other malignancies. Both ferroptosis and the epigenetic machinery are heavily influenced by oxidative stress and iron metabolism changes. Yet, only a limited number of epigenetic enzymes and modifications have been identified as ferroptosis regulators. In this study, we found that MM1 multiple myeloma cells are sensitive to ferroptosis induction and epigenetic reprogramming by RSL3, irrespective of their glucocorticoid-sensitivity status. LC-MS/MS analysis revealed the formation of non-heme iron-histone complexes and altered expression of histone modifications associated with DNA repair and cellular senescence. In line with this observation, EPIC BeadChip measurements of significant DNA methylation changes in ferroptotic myeloma cells demonstrated an enrichment of CpG probes located in genes associated with cell cycle progression and senescence, such as Nuclear Receptor Subfamily 4 Group A member 2 (NR4A2). Overall, our data show that ferroptotic cell death is associated with an epigenomic stress response that might advance the therapeutic applicability of ferroptotic compounds.


Assuntos
Senescência Celular , Metilação de DNA , DNA de Neoplasias/metabolismo , Ferroptose , Histonas/metabolismo , Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/metabolismo , Código das Histonas , Humanos , Mieloma Múltiplo/patologia
15.
Molecules ; 26(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34279439

RESUMO

COVID-19 is a pandemic disease caused by the SARS-CoV-2 virus, which is potentially fatal for vulnerable individuals. Disease management represents a challenge for many countries, given the shortage of medicines and hospital resources. The objective of this work was to review the medicinal plants, foods and natural products showing scientific evidence for host protection against various types of coronaviruses, with a focus on SARS-CoV-2. Natural products that mitigate the symptoms caused by various coronaviruses are also presented. Particular attention was placed on natural products that stabilize the Renin-Angiotensin-Aldosterone System (RAAS), which has been associated with the entry of the SARS-CoV-2 into human cells.


Assuntos
Produtos Biológicos/farmacologia , Coronavirus/efeitos dos fármacos , Fitoterapia/métodos , Extratos Vegetais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Antivirais/metabolismo , Antivirais/farmacologia , Produtos Biológicos/metabolismo , COVID-19/virologia , Humanos , Pandemias , Extratos Vegetais/metabolismo , Plantas/química , Sistema Renina-Angiotensina/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
16.
Hum Reprod ; 35(2): 293-307, 2020 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-32112081

RESUMO

STUDY QUESTION: Does oocyte maturation under lipolytic conditions have detrimental carry-over effects on post-hatching embryo development of good-quality blastocysts after transfer? SUMMARY ANSWER: Surviving, morphologically normal blastocysts derived from bovine oocytes that matured under lipotoxic conditions exhibit long-lasting cellular dysfunction at the transcriptomic and metabolic levels, which coincides with retarded post-hatching embryo development. WHAT IS KNOWN ALREADY: There is increasing evidence showing that following maturation in pathophysiologically relevant lipotoxic conditions (as in obesity or metabolic syndrome), surviving blastocysts of good (transferable) morphological quality have persistent transcriptomic and epigenetic alteration even when in vitro embryo culture takes place under standard conditions. However, very little is known about subsequent development in the uterus after transfer. STUDY DESIGN, SIZE, DURATION: Bovine oocytes were matured in vitro in the presence of pathophysiologically relevant, high non-esterified fatty acid (NEFA) concentrations (HIGH PA), or in basal NEFA concentrations (BASAL) as a physiological control. Eight healthy multiparous non-lactating Holstein cows were used for embryo transfers. Good-quality blastocysts (pools of eight) were transferred per cow, and cows were crossed over for treatments in the next replicate. Embryos were recovered 7 days later and assessed for post-hatching development, phenotypic features and gene expression profile. Blastocysts from solvent-free and NEFA-free maturation (CONTROL) were also tested for comparison. PARTICIPANTS/MATERIALS, SETTING, METHODS: Recovered Day 14 embryos were morphologically assessed and dissected into embryonic disk (ED) and extraembryonic tissue (EXT). Samples of EXT were cultured for 24 h to assess cellular metabolic activity (glucose and pyruvate consumption and lactate production) and embryos' ability to signal for maternal recognition of pregnancy (interferon-τ secretion; IFN-τ). ED and EXT samples were subjected to RNA sequencing to evaluate the genome-wide transcriptome patterns. MAIN RESULTS AND THE ROLE OF CHANCE: The embryo recovery rate at Day 14 p.i. was not significantly different among treatment groups (P > 0.1). However, higher proportions of HIGH PA embryos were retarded in growth (in spherical stage) compared to the more elongated tubular stage embryos in the BASAL group (P < 0.05). Focusing on the normally developed tubular embryos in both groups, HIGH PA exposure resulted in altered cellular metabolism and altered transcriptome profile particularly in pathways related to redox-regulating mechanisms, apoptosis, cellular growth, interaction and differentiation, energy metabolism and epigenetic mechanisms, compared to BASAL embryos. Maturation under BASAL conditions did not have any significant effects on post-hatching development and cellular functions compared to CONTROL. LARGE-SCALE DATA: The datasets of RNA sequencing analysis are available in the NCBI's Gene Expression Omnibus (GEO) repository, series accession number GSE127889 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE127889). Datasets of differentially expressed genes and their gene ontology functions are available in the Mendeley datasets at http://dx.doi.org/10.17632/my2z7dvk9j.2. LIMITATIONS, REASONS FOR CAUTION: The bovine model was used here to allow non-invasive embryo transfer and post-hatching recovery on Day 14. There are physiological differences in some characteristics of post-hatching embryo development between human and cows, such as embryo elongation and trophoblastic invasion. However, the main carry-over effects of oocyte maturation under lipolytic conditions described here are evident at the cellular level and therefore may also occur during post-hatching development in other species including humans. In addition, post-hatching development was studied here under a healthy uterine environment to focus on carry-over effects originating from the oocyte, whereas additional detrimental effects may be induced by maternal metabolic disorders due to adverse changes in the uterine microenvironment. RNA sequencing results were not verified by qPCR, and no solvent control was included. WIDER IMPLICATIONS OF THE FINDINGS: Our observations may increase the awareness of the importance of maternal metabolic stress at the level of the preovulatory oocyte in relation to carry-over effects that may persist in the transferrable embryos. It should further stimulate new research about preventive and protective strategies to optimize maternal metabolic health around conception to maximize embryo viability and thus fertility outcome. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the Flemish Research Fund (FWO grant 11L8716N and FWO project 42/FAO10300/6541). The authors declare there are no conflicts of interest.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Transcriptoma , Animais , Blastocisto , Bovinos , Transferência Embrionária , Feminino , Humanos , Oócitos , Gravidez
17.
Brief Bioinform ; 16(2): 216-31, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24162173

RESUMO

Over the past two decades, pattern mining techniques have become an integral part of many bioinformatics solutions. Frequent itemset mining is a popular group of pattern mining techniques designed to identify elements that frequently co-occur. An archetypical example is the identification of products that often end up together in the same shopping basket in supermarket transactions. A number of algorithms have been developed to address variations of this computationally non-trivial problem. Frequent itemset mining techniques are able to efficiently capture the characteristics of (complex) data and succinctly summarize it. Owing to these and other interesting properties, these techniques have proven their value in biological data analysis. Nevertheless, information about the bioinformatics applications of these techniques remains scattered. In this primer, we introduce frequent itemset mining and their derived association rules for life scientists. We give an overview of various algorithms, and illustrate how they can be used in several real-life bioinformatics application domains. We end with a discussion of the future potential and open challenges for frequent itemset mining in the life sciences.


Assuntos
Algoritmos , Mineração de Dados/estatística & dados numéricos , Animais , Análise por Conglomerados , Biologia Computacional , Perfilação da Expressão Gênica/estatística & dados numéricos , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Humanos , Reconhecimento Automatizado de Padrão/estatística & dados numéricos , Polimorfismo de Nucleotídeo Único , Software
18.
Brain Behav Immun ; 64: 103-115, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28390980

RESUMO

Stroke represents one of the first causes of mortality and morbidity worldwide. We evaluated the therapeutic potential of a novel semi-synthetic spirosteroid sapogenin derivative "S15" in a transient middle cerebral artery occlusion (tMCAO) focal ischemia model in rat. S15-treated rats had significantly reduced infarct volumes and improved neurological functions at 24h post-reperfusion, compared with ischemia. Corresponding gene expression changes in brain were characterized by mRNA sequencing and qPCR approaches. Next, we applied geneset, pathway and transcription factor motif enrichment analysis to identify relevant signaling networks responsible for neuronal damage upon ischemia-reperfusion or neuroprotection upon pretreatment with S15. As expected, ischemia-reperfusion brain damage strongly modulates transcriptional programs associated with immune responses, increased differentiation of immune cells as well as reduced (cat)ion transport and synaptic activity. Interestingly, S15-dependent neuroprotection regulates inflammation-associated genes involved in phagosome specific resolution of tissue damage, chemotaxis and anti-inflammatory alternative activation of microglia. Altogether our transcriptome wide RNA sequencing and integrated pathway analysis provides new clues in the neuroprotective properties of a novel spirosteroid S15 or neuronal damage in rat brains subjected to ischemia, which opens new perspectives for successful treatment of stroke.


Assuntos
Isquemia Encefálica/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Sapogeninas/administração & dosagem , Acidente Vascular Cerebral/metabolismo , Transcriptoma , Animais , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Ratos Wistar , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico
19.
Bioorg Med Chem Lett ; 26(20): 5032-5038, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27612544

RESUMO

The synthesis and in vitro properties of six analogues of the selective glucocorticoid receptor (GR) agonist GSK866, bearing a warhead for covalent linkage to the glucocorticoid receptor, is described.


Assuntos
Receptores de Glucocorticoides/agonistas , Sítios de Ligação , Desenho de Fármacos , Hidrocortisona/metabolismo , Cinética , Receptores de Glucocorticoides/metabolismo
20.
Nucleic Acids Res ; 42(20): e157, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25237057

RESUMO

Monoallelic gene expression is typically initiated early in the development of an organism. Dysregulation of monoallelic gene expression has already been linked to several non-Mendelian inherited genetic disorders. In humans, DNA-methylation is deemed to be an important regulator of monoallelic gene expression, but only few examples are known. One important reason is that current, cost-affordable truly genome-wide methods to assess DNA-methylation are based on sequencing post-enrichment. Here, we present a new methodology based on classical population genetic theory, i.e. the Hardy-Weinberg theorem, that combines methylomic data from MethylCap-seq with associated SNP profiles to identify monoallelically methylated loci. Applied on 334 MethylCap-seq samples of very diverse origin, this resulted in the identification of 80 genomic regions featured by monoallelic DNA-methylation. Of these 80 loci, 49 are located in genic regions of which 25 have already been linked to imprinting. Further analysis revealed statistically significant enrichment of these loci in promoter regions, further establishing the relevance and usefulness of the method. Additional validation was done using both 14 whole-genome bisulfite sequencing data sets and 16 mRNA-seq data sets. Importantly, the developed approach can be easily applied to other enrichment-based sequencing technologies, like the ChIP-seq-based identification of monoallelic histone modifications.


Assuntos
Alelos , Metilação de DNA , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Loci Gênicos , Genômica , Humanos , Análise de Sequência de RNA
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