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1.
AORN J ; 119(3): 198-209, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407362

RESUMO

Moyamoya disease is a progressive cerebrovascular disorder for which there is no cure. It is characterized by narrowing of and occlusions in the blood vessels that supply the brain, which causes a fine vascular network to develop to serve as collateral pathways. Moyamoya disease can lead to a reduction of blood flow to the brain and increase the risk of stroke. Patients with moyamoya disease may present with ischemic or hemorrhagic complications. Treatment options may involve medical management or surgical revascularization (indirect, direct, or a combined approach). The encephaloduroarteriosynangiosis procedure is a form of indirect revascularization in which a portion of the superficial temporal artery is moved from the scalp to the brain surface. Regardless of the approach, the goal of revascularization is to improve blood flow to the affected area to prevent additional infarcts; the encephaloduroarteriosynangiosis procedure is a viable option to help prevent additional neurologic decline.


Assuntos
Doença de Moyamoya , Acidente Vascular Cerebral , Humanos , Doença de Moyamoya/cirurgia , Encéfalo , Pacientes
2.
Mol Metab ; 78: 101833, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37925021

RESUMO

OBJECTIVE: The learned associations between sensory cues (e.g., taste, smell) and nutritive value (e.g., calories, post-ingestive signaling) of foods powerfully influences our eating behavior [1], but the neural circuits that mediate these associations are not well understood. Here, we examined the role of agouti-related protein (AgRP)-expressing neurons - neurons which are critical drivers of feeding behavior [2; 3] - in mediating flavor-nutrient learning (FNL). METHODS: Because mice prefer flavors associated with AgRP neuron activity suppression [4], we examined how optogenetic stimulation of AgRP neurons during intake influences FNL, and used fiber photometry to determine how endogenous AgRP neuron activity tracks associations between flavors and nutrients. RESULTS: We unexpectedly found that tonic activity in AgRP neurons during FNL potentiated, rather than prevented, the development of flavor preferences. There were notable sex differences in the mechanisms for this potentiation. Specifically, in male mice, AgRP neuron activity increased flavor consumption during FNL training, thereby strengthening the association between flavors and nutrients. In female mice, AgRP neuron activity enhanced flavor-nutrient preferences independently of consumption during training, suggesting that AgRP neuron activity enhances the reward value of the nutrient-paired flavor. Finally, in vivo neural activity analyses demonstrated that acute AgRP neuron dynamics track the association between flavors and nutrients in both sexes. CONCLUSIONS: Overall, these data (1) demonstrate that AgRP neuron activity enhances associations between flavors and nutrients in a sex-dependent manner and (2) reveal that AgRP neurons track and rapidly update these associations. Taken together, our findings provide new insight into the role of AgRP neurons in assimilating sensory and nutritive signals for food reinforcement.


Assuntos
Ingestão de Alimentos , Comportamento Alimentar , Animais , Feminino , Masculino , Camundongos , Proteína Relacionada com Agouti/metabolismo , Ingestão de Alimentos/fisiologia , Ingestão de Energia , Comportamento Alimentar/fisiologia , Neurônios/metabolismo
3.
bioRxiv ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37786670

RESUMO

Objective: The learned associations between sensory cues (e.g., taste, smell) and nutritive value (e.g., calories, post-ingestive signaling) of foods powerfully influences our eating behavior [1], but the neural circuits that mediate these associations are not well understood. Here, we examined the role of agouti-related protein (AgRP)-expressing neurons - neurons which are critical drivers of feeding behavior [2; 3] - in mediating flavor-nutrient learning (FNL). Methods: Because mice prefer flavors associated with AgRP neuron activity suppression [4], we examined how optogenetic stimulation of AgRP neurons during intake influences FNL, and used fiber photometry to determine how endogenous AgRP neuron activity tracks associations between flavors and nutrients. Results: We unexpectedly found that tonic activity in AgRP neurons during FNL potentiated, rather than prevented, the development of flavor preferences. There were notable sex differences in the mechanisms for this potentiation. Specifically, in male mice, AgRP neuron activity increased flavor consumption during FNL training, thereby strengthening the association between flavors and nutrients. In female mice, AgRP neuron activity enhanced flavor-nutrient preferences independently of consumption during training, suggesting that AgRP neuron activity enhances the reward value of the nutrient-paired flavor. Finally, in vivo neural activity analyses demonstrated that acute AgRP neuron dynamics track the association between flavors and nutrients in both sexes. Conclusions: Overall, these data (1) demonstrate that AgRP neuron activity enhances associations between flavors and nutrients in a sex-dependent manner and (2) reveal that AgRP neurons track and update these associations on fast timescales. Taken together, our findings provide new insight into the role of AgRP neurons in assimilating sensory and nutritive signals for food reinforcement.

4.
PLoS One ; 18(7): e0289120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37486909

RESUMO

The current food chain both contributes to, and is affected by, climate change. While GHG emissions and emissions to water and soil are a problem for the whole food chain, the majority of such emissions and the major solutions to them can be found in the farming and land use sector. The farming system needs to reduce its greenhouse-gas emissions and adapt its supply chain to cope with climate change. A broad variety of payment tools have been proposed to motivate farmers and landowners to take certain actions to reduce greenhouse gas emissions and encourage the protection or restoration of natural resources. The protocol described here (OSF preregistration https://doi.org/10.17605/OSF.IO/STGQ6) outlines the methodology for a systematic review to explore how financial mechanisms such as green bonds can provide incentives to agri-food sector to support environmental sustainability and ecosystem service delivery through land-use change. Our primary research question is: how do financial mechanisms incentivize land restoration? Studies will be categorized according to the types of financial mechanisms, their characteristics, methods of land restoration and their impact on mitigating agri-food footprint. The results are expected to increase our understanding about the design of financing tools currently used to accelerate nature restoration. Moreover, they will inform us about the effectiveness of deploying such tools on rural communities, food companies and landowners.


Assuntos
Ecossistema , Gases de Efeito Estufa , Efeito Estufa , Conservação dos Recursos Naturais/métodos , Solo/química , Agricultura/métodos , Revisões Sistemáticas como Assunto
5.
J Infect Dis ; 225(10): 1832-1840, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-33693706

RESUMO

Previous studies have identified whole-blood transcriptional risk and disease signatures for tuberculosis; however, several lines of evidence suggest that these signatures primarily reflect bacterial burden, which increases before symptomatic disease. We found that the peripheral blood transcriptome of mice with contained Mycobacterium tuberculosis infection (CMTI) has striking similarities to that of humans with active tuberculosis and that a signature derived from these mice predicts human disease with accuracy comparable to that of signatures derived directly from humans. A set of genes associated with immune defense are up-regulated in mice with CMTI but not in humans with active tuberculosis, suggesting that their up-regulation is associated with bacterial containment. A signature comprising these genes predicts both protection from tuberculosis disease and successful treatment at early time points where current signatures are not predictive. These results suggest that detailed study of the CMTI model may enable identification of biomarkers for human tuberculosis.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Biomarcadores , Humanos , Camundongos , Transcriptoma
6.
Cell Rep ; 35(9): 109195, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34077724

RESUMO

Metabolic reprogramming powers and polarizes macrophage functions, but the nature and regulation of this response during infection with pathogens remain controversial. In this study, we characterize the metabolic and transcriptional responses of murine macrophages to Mycobacterium tuberculosis (Mtb) in order to disentangle the underlying mechanisms. We find that type I interferon (IFN) signaling correlates with the decreased glycolysis and mitochondrial damage that is induced by live, but not killed, Mtb. Macrophages lacking the type I IFN receptor (IFNAR) maintain glycolytic flux and mitochondrial function during Mtb infection in vitro and in vivo. IFNß itself restrains the glycolytic shift of inflammatory macrophages and initiates mitochondrial stress. We confirm that type I IFN acts upstream of mitochondrial damage using macrophages lacking the protein STING. We suggest that a type I IFN-mitochondrial feedback loop controls macrophage responses to mycobacteria and that this could contribute to pathogenesis across a range of diseases.


Assuntos
Metabolismo Energético , Interferon Tipo I/metabolismo , Macrófagos/metabolismo , Mycobacterium tuberculosis/fisiologia , Tuberculose/metabolismo , Animais , Glicólise , Temperatura Alta , Proteínas de Membrana , Camundongos , Mitocôndrias/metabolismo , Transdução de Sinais , Estresse Fisiológico , Transcrição Gênica
7.
PLoS Pathog ; 16(7): e1008655, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32673357

RESUMO

Progress in tuberculosis vaccine development is hampered by an incomplete understanding of the immune mechanisms that protect against infection with Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis. Although the M72/ASOE1 trial yielded encouraging results (54% efficacy in subjects with prior exposure to Mtb), a highly effective vaccine against adult tuberculosis remains elusive. We show that in a mouse model, establishment of a contained and persistent yet non-pathogenic infection with Mtb ("contained Mtb infection", CMTB) rapidly and durably reduces tuberculosis disease burden after re-exposure through aerosol challenge. Protection is associated with elevated activation of alveolar macrophages, the first cells that respond to inhaled Mtb, and accelerated recruitment of Mtb-specific T cells to the lung parenchyma. Systems approaches, as well as ex vivo functional assays and in vivo infection experiments, demonstrate that CMTB reconfigures tissue resident alveolar macrophages via low grade interferon-γ exposure. These studies demonstrate that under certain circumstances, the continuous interaction of the immune system with Mtb is beneficial to the host by maintaining elevated innate immune responses.


Assuntos
Modelos Animais de Doenças , Mycobacterium tuberculosis/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose/imunologia , Tuberculose/virologia , Animais , Macrófagos Alveolares/imunologia , Camundongos
8.
Proc Natl Acad Sci U S A ; 117(27): 15789-15798, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32581129

RESUMO

Patients infected with influenza are at high risk of secondary bacterial infection, which is a major proximate cause of morbidity and mortality. We have shown that in mice, prior infection with influenza results in increased inflammation and mortality upon Staphylococcus aureus infection, recapitulating the human disease. Lipidomic profiling of the lungs of superinfected mice revealed an increase in CYP450 metabolites during lethal superinfection. These lipids are endogenous ligands for the nuclear receptor PPARα, and we demonstrate that Ppara-/- mice are less susceptible to superinfection than wild-type mice. PPARα is an inhibitor of NFκB activation, and transcriptional profiling of cells isolated by bronchoalveolar lavage confirmed that influenza infection inhibits NFκB, thereby dampening proinflammatory and prosurvival signals. Furthermore, network analysis indicated an increase in necrotic cell death in the lungs of superinfected mice compared to mice infected with S. aureus alone. Consistent with this, we observed reduced NFκB-mediated inflammation and cell survival signaling in cells isolated from the lungs of superinfected mice. The kinase RIPK3 is required to induce necrotic cell death and is strongly induced in cells isolated from the lungs of superinfected mice compared to mice infected with S. aureus alone. Genetic and pharmacological perturbations demonstrated that PPARα mediates RIPK3-dependent necroptosis and that this pathway plays a central role in mortality following superinfection. Thus, we have identified a molecular circuit in which infection with influenza induces CYP450 metabolites that activate PPARα, leading to increased necrotic cell death in the lung which correlates with the excess mortality observed in superinfection.


Assuntos
Inflamação/genética , Influenza Humana/genética , PPAR alfa/genética , Infecções Estafilocócicas/genética , Superinfecção/genética , Animais , Lavagem Broncoalveolar/métodos , Coinfecção/genética , Coinfecção/microbiologia , Coinfecção/mortalidade , Sistema Enzimático do Citocromo P-450/genética , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Inflamação/microbiologia , Inflamação/mortalidade , Influenza Humana/microbiologia , Influenza Humana/mortalidade , Pulmão/microbiologia , Pulmão/patologia , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Camundongos , Camundongos Knockout , Necroptose/genética , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/mortalidade , Superinfecção/mortalidade
9.
Sci Immunol ; 4(37)2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31350281

RESUMO

Alveolar macrophages (AMs) are the first cells to be infected during Mycobacterium tuberculosis (M.tb.) infection. Thus, the AM response to infection is the first of many steps leading to initiation of the adaptive immune response required for efficient control of infection. A hallmark of M.tb. infection is the slow initiation of the adaptive response, yet the mechanisms responsible for this are largely unknown. To study the initial AM response to infection, we developed a system to identify, sort, and analyze M.tb.-infected AMs from the lung within the first 10 days of infection. In contrast to what has been previously described using in vitro systems, M.tb.-infected AMs up-regulate a cell-protective antioxidant transcriptional signature that is dependent on the lung environment but not bacterial virulence. Computational approaches including pathway analysis and transcription factor motif enrichment analysis identify NRF2 as a master regulator of the response. Using knockout mouse models, we demonstrate that NRF2 drives expression of the cell-protective signature in AMs and impairs the control of early bacterial growth. AMs up-regulate a substantial pro-inflammatory response to M.tb. infection only 10 days after infection, yet comparisons with bystander AMs from the same infected animals demonstrate that M.tb.-infected AMs generate a less robust inflammatory response than the uninfected cells around them. Our findings demonstrate that the initial macrophage response to M.tb. in the lung is far less inflammatory than has previously been described by in vitro systems and may impede the overall host response to infection.


Assuntos
Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Mycobacterium tuberculosis/imunologia , Fator 2 Relacionado a NF-E2/metabolismo , Transcrição Gênica , Tuberculose Pulmonar/genética , Tuberculose Pulmonar/imunologia , Animais , Feminino , Macrófagos Alveolares/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia
10.
PLoS One ; 14(3): e0213605, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30883583

RESUMO

BACKGROUND: Modeling contributes to health program planning by allowing users to estimate future outcomes that are otherwise difficult to evaluate. However, modeling results are often not easily translated into practical policies. This paper examines the barriers and enabling factors that can allow models to better inform health decision-making. DESCRIPTION: The Decision Makers' Program Planning Tool (DMPPT) and its successor, DMPPT 2, are illustrative examples of modeling tools that have been used to inform health policy. Their use underpinned Voluntary Medical Male Circumcision (VMMC) scale-up for HIV prevention in southern and eastern Africa. Both examine the impact and cost-effectiveness of VMMC scale-up, with DMPPT used initially in global advocacy and DMPPT 2 then providing VMMC coverage estimates by client age and subnational region for use in country-specific program planning. Their application involved three essential steps: identifying and engaging a wide array of stakeholders from the outset, reaching consensus on key assumptions and analysis plans, and convening data validation meetings with critical stakeholders. The subsequent DMPPT 2 Online is a user-friendly tool for in-country modeling analyses and continuous program planning and monitoring. LESSONS LEARNED: Through three iterations of the DMPPT applied to VMMC, a comprehensive framework with six steps was identified: (1) identify a champion, (2) engage stakeholders early and often, (3) encourage consensus, (4) customize analyses, (5), build capacity, and (6) establish a plan for sustainability. This framework could be successfully adapted to other HIV prevention programs to translate modeling results to policy and programming. CONCLUSIONS: Models can be used to mobilize support, strategically plan, and monitor key programmatic elements, but they can also help inform policy environments in which programs are conceptualized and implemented to achieve results. The ways in which modeling has informed VMMC programs and policy may be applicable to an array of other health interventions.


Assuntos
Circuncisão Masculina/estatística & dados numéricos , Sistemas de Apoio a Decisões Clínicas , Infecções por HIV/prevenção & controle , Política de Saúde , Programas Nacionais de Saúde , Programas Voluntários , Adolescente , Adulto , África Oriental , África Austral , Criança , Circuncisão Masculina/economia , Análise Custo-Benefício , Tomada de Decisões , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Projetos de Pesquisa , Adulto Jovem
11.
Clin Infect Dis ; 66(suppl_3): S166-S172, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29617778

RESUMO

Background: The new World Health Organization and Joint United Nations Programme on HIV/AIDS strategic framework for voluntary medical male circumcision (VMMC) aims to increase VMMC coverage among males aged 10-29 years in priority settings to 90% by 2021. We use mathematical modeling to assess the likelihood that selected countries will achieve this objective, given their historical VMMC progress and current implementation options. Methods: We use the Decision Makers' Program Planning Toolkit, version 2, to examine 4 ambitious but feasible scenarios for scaling up VMMC coverage from 2017 through 2021, inclusive in Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Uganda, and Zimbabwe. Results: Tanzania is the only country that would reach the goal of 90% VMMC coverage in 10- to 29-year-olds by the end of 2021 in the scenarios assessed, and this was true in 3 of the scenarios studied. Mozambique, South Africa, and Lesotho would come close to reaching the objective only in the most ambitious scenario examined. Conclusions: Major changes in VMMC implementation in most countries will be required to increase the proportion of circumcised 10- to 29-year-olds to 90% by the end of 2021. Scaling up VMMC coverage in males aged 10-29 years will require significantly increasing the number of circumcisions provided to 10- to 14-year-olds and 15- to 29-year-olds.


Assuntos
Circuncisão Masculina/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Modelos Estatísticos , Programas Nacionais de Saúde , Adolescente , Adulto , África Subsaariana , Fatores Etários , Criança , Circuncisão Masculina/economia , Análise Custo-Benefício , Infecções por HIV/transmissão , Humanos , Masculino , Nações Unidas , Adulto Jovem
14.
PLoS One ; 11(10): e0164144, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27783637

RESUMO

BACKGROUND: Zimbabwe aims to increase circumcision coverage to 80% among 13- to 29-year-olds. However, implementation data suggest that high coverage among men ages 20 and older may not be achievable without efforts specifically targeted to these men, incurring additional costs per circumcision. Scale-up scenarios were created based on trends in implementation data in Zimbabwe, and the cost-effectiveness of increasing efforts to recruit clients ages 20-29 was examined. METHODS: Zimbabwe voluntary medical male circumcision (VMMC) program data were used to project trends in male circumcision coverage by age into the future. The projection informed a base scenario in which, by 2018, the country achieves 80% circumcision coverage among males ages 10-19 and lower levels of coverage among men above age 20. The Zimbabwe DMPPT 2.0 model was used to project costs and impacts, assuming a US$109 VMMC unit cost in the base scenario and a 3% discount rate. Two other scenarios assumed that the program could increase coverage among clients ages 20-29 with a corresponding increase in unit cost for these age groups. RESULTS: When circumcision coverage among men ages 20-29 is increased compared with a base scenario reflecting current implementation trends, fewer VMMCs are required to avert one infection. If more than 50% additional effort (reflected as multiplying the unit cost by >1.5) is required to double the increase in coverage among this age group compared with the base scenario, the cost per HIV infection averted is higher than in the base scenario. CONCLUSIONS: Although increased investment in recruiting VMMC clients ages 20-29 may lead to greater overall impact if recruitment efforts are successful, it may also lead to lower cost-effectiveness, depending on the cost of increasing recruitment. Programs should measure the relationship between increased effort and increased ability to attract this age group.


Assuntos
Circuncisão Masculina/economia , Análise Custo-Benefício , Modelos Teóricos , Programas Voluntários/economia , Adolescente , Adulto , Criança , Infecções por HIV/economia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde/economia , Adulto Jovem , Zimbábue/epidemiologia
15.
PLoS One ; 11(7): e0156776, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27410687

RESUMO

BACKGROUND: Voluntary medical male circumcision (VMMC) for HIV prevention has been a priority for Swaziland since 2009. Initially focusing on men ages 15-49, the Ministry of Health reduced the minimum age for VMMC from 15 to 10 years in 2012, given the existing demand among 10- to 15-year-olds. To understand the implications of focusing VMMC service delivery on specific age groups, the MOH undertook a modeling exercise to inform policy and implementation in 2013-2014. METHODS AND FINDINGS: The impact and cost of circumcising specific age groups were assessed using the Decision Makers' Program Planning Tool, Version 2.0 (DMPPT 2.0), a simple compartmental model. We used age-specific HIV incidence from the Swaziland HIV Incidence Measurement Survey (SHIMS). Population, mortality, births, and HIV prevalence were imported from a national Spectrum/Goals model recently updated in consultation with country stakeholders. Baseline male circumcision prevalence was derived from the most recent Swaziland Demographic and Health Survey. The lowest numbers of VMMCs per HIV infection averted are achieved when males ages 15-19, 20-24, 25-29, and 30-34 are circumcised, although the uncertainty bounds for the estimates overlap. Circumcising males ages 25-29 and 20-24 provides the most immediate reduction in HIV incidence. Circumcising males ages 15-19, 20-24, and 25-29 provides the greatest magnitude incidence reduction within 15 years. The lowest cost per HIV infection averted is achieved by circumcising males ages 15-34: $870 U.S. dollars (USD). CONCLUSIONS: The potential impact, cost, and cost-effectiveness of VMMC scale-up in Swaziland are not uniform. They vary by the age group of males circumcised. Based on the results of this modeling exercise, the Ministry of Health's Swaziland Male Circumcision Strategic and Operational Plan 2014-2018 adopted an implementation strategy that calls for circumcision to be scaled up to 50% coverage for neonates, 80% among males ages 10-29, and 55% among males ages 30-34.


Assuntos
Circuncisão Masculina , Infecções por HIV/prevenção & controle , Programas Nacionais de Saúde , Programas Voluntários , Adolescente , Adulto , Fatores Etários , Circuncisão Masculina/economia , Circuncisão Masculina/estatística & dados numéricos , Análise Custo-Benefício , Essuatíni/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Programas Nacionais de Saúde/economia , Programas Voluntários/economia , Adulto Jovem
17.
EMBO J ; 34(9): 1244-58, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25755249

RESUMO

LXR-cofactor complexes activate the gene expression program responsible for cholesterol efflux in macrophages. Inflammation antagonizes this program, resulting in foam cell formation and atherosclerosis; however, the molecular mechanisms underlying this antagonism remain to be fully elucidated. We use promoter enrichment-quantitative mass spectrometry (PE-QMS) to characterize the composition of gene regulatory complexes assembled at the promoter of the lipid transporter Abca1 following downregulation of its expression. We identify a subset of proteins that show LXR ligand- and binding-dependent association with the Abca1 promoter and demonstrate they differentially control Abca1 expression. We determine that NCOA5 is linked to inflammatory Toll-like receptor (TLR) signaling and establish that NCOA5 functions as an LXR corepressor to attenuate Abca1 expression. Importantly, TLR3-LXR signal crosstalk promotes recruitment of NCOA5 to the Abca1 promoter together with loss of RNA polymerase II and reduced cholesterol efflux. Together, these data significantly expand our knowledge of regulatory inputs impinging on the Abca1 promoter and indicate a central role for NCOA5 in mediating crosstalk between pro-inflammatory and anti-inflammatory pathways that results in repression of macrophage cholesterol efflux.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Colesterol/metabolismo , Macrófagos/metabolismo , Coativadores de Receptor Nuclear/genética , Receptores Nucleares Órfãos/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Feminino , Regulação da Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Receptores X do Fígado , Espectrometria de Massas/métodos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Coativadores de Receptor Nuclear/metabolismo , Receptores Nucleares Órfãos/metabolismo , Regiões Promotoras Genéticas , RNA Polimerase II/metabolismo , Transdução de Sinais , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo
18.
PLoS Genet ; 10(12): e1004828, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25474352

RESUMO

We report the first systems biology investigation of regulators controlling arterial plaque macrophage transcriptional changes in response to lipid lowering in vivo in two distinct mouse models of atherosclerosis regression. Transcriptome measurements from plaque macrophages from the Reversa mouse were integrated with measurements from an aortic transplant-based mouse model of plaque regression. Functional relevance of the genes detected as differentially expressed in plaque macrophages in response to lipid lowering in vivo was assessed through analysis of gene functional annotations, overlap with in vitro foam cell studies, and overlap of associated eQTLs with human atherosclerosis/CAD risk SNPs. To identify transcription factors that control plaque macrophage responses to lipid lowering in vivo, we used an integrative strategy--leveraging macrophage epigenomic measurements--to detect enrichment of transcription factor binding sites upstream of genes that are differentially expressed in plaque macrophages during regression. The integrated analysis uncovered eight transcription factor binding site elements that were statistically overrepresented within the 5' regulatory regions of genes that were upregulated in plaque macrophages in the Reversa model under maximal regression conditions and within the 5' regulatory regions of genes that were upregulated in the aortic transplant model during regression. Of these, the TCF/LEF binding site was present in promoters of upregulated genes related to cell motility, suggesting that the canonical Wnt signaling pathway may be activated in plaque macrophages during regression. We validated this network-based prediction by demonstrating that ß-catenin expression is higher in regressing (vs. control group) plaques in both regression models, and we further demonstrated that stimulation of canonical Wnt signaling increases macrophage migration in vitro. These results suggest involvement of canonical Wnt signaling in macrophage emigration from the plaque during lipid lowering-induced regression, and they illustrate the discovery potential of an epigenome-guided, systems approach to understanding atherosclerosis regression.


Assuntos
Hipolipemiantes/uso terapêutico , Macrófagos/metabolismo , Macrófagos/patologia , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/genética , Transcriptoma , Via de Sinalização Wnt , Animais , Células Cultivadas , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/fisiologia , Feminino , Perfilação da Expressão Gênica , Genoma/efeitos dos fármacos , Hipolipemiantes/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise em Microsséries , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Receptores de LDL/genética , Indução de Remissão , Transcriptoma/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
19.
Proc Natl Acad Sci U S A ; 111(29): 10666-71, 2014 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-24994901

RESUMO

Cross-talk between sterol regulatory pathways and inflammatory pathways has been demonstrated to significantly impact the development of both atherosclerosis and infectious disease. The oxysterol 25-hydroxycholesterol (25HC) plays multiple roles in lipid biosynthesis and immunity. We recently used a systems biology approach to identify 25HC as an innate immune mediator that had a predicted role in atherosclerosis and we demonstrated a role for 25HC in foam cell formation. Here, we show that this mediator also has several complex roles in the antiviral response. The host response to viruses involves gene regulatory circuits with multiple feedback loops and we show here that 25HC acts as an amplifier of inflammatory signaling in macrophages. We determined that 25HC amplifies inflammatory signaling, at least in part, by mediating the recruitment of the AP-1 components FBJ osteosarcoma oncogene (FOS) and jun proto-oncogene (JUN) to the promoters of a subset of Toll-like receptor-responsive genes. Consistent with previous reports, we found that 25HC inhibits in vitro infection of airway epithelial cells by influenza. Surprisingly, we found that deletion of Ch25h, the gene encoding the enzyme responsible for 25HC production, is protective in a mouse model of influenza infection as a result of decreased inflammatory-induced pathology. Thus, our study demonstrates, for the first time to our knowledge, that in addition to its direct antiviral role, 25HC also regulates transcriptional responses and acts as an amplifier of inflammation via AP-1 and that the resulting alteration in inflammatory response leads to increased tissue damage in mice following infection with influenza.


Assuntos
Hidroxicolesteróis/farmacologia , Inflamação/metabolismo , Inflamação/patologia , Transdução de Sinais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Retroalimentação Fisiológica/efeitos dos fármacos , Humanos , Influenza Humana/metabolismo , Influenza Humana/patologia , Receptores X do Fígado , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores Nucleares Órfãos/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/patologia , Poli I-C/farmacologia , Proto-Oncogene Mas , Esteroide Hidroxilases/metabolismo , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica/efeitos dos fármacos
20.
J Acquir Immune Defic Syndr ; 66 Suppl 2: S193-9, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24918595

RESUMO

BACKGROUND AND METHODS: By December 2013, it was estimated that close to 6 million men had been circumcised in the 14 priority countries for scaling up voluntary medical male circumcision (VMMC), the majority being adolescents (10-19 years). This article discusses why efforts to scale up VMMC should prioritize adolescent men, drawing from new evidence and experiences at the international, country, and service delivery levels. Furthermore, we review the extent to which VMMC programs have reached adolescents, addressed their specific needs, and can be linked to their sexual and reproductive health and other key services. RESULTS AND DISCUSSION: In priority countries, adolescents represent 34%-55% of the target population to be circumcised, whereas program data from these countries show that adolescents represent between 35% and 74% of the circumcised men. VMMC for adolescents has several advantages: uptake of services among adolescents is culturally and socially more acceptable than for adults; there are fewer barriers regarding sexual abstinence during healing or female partner pressures; VMMC performed before the age of sexual debut has maximum long-term impact on reducing HIV risk at the individual level and consequently reduces the risk of transmission in the population. Offered as a comprehensive package, adolescent VMMC can potentially increase public health benefits and offers opportunities for addressing gender norms. Additional research is needed to assess whether current VMMC services address the specific needs of adolescent clients, to test adapted tools, and to assess linkages between VMMC and other adolescent-focused HIV, health, and social services.


Assuntos
Circuncisão Masculina/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Adolescente , Humanos , Masculino , Saúde Reprodutiva , Comportamento Sexual
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