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1.
Exp Clin Endocrinol Diabetes ; 132(5): 267-278, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38382644

RESUMO

Diabetes mellitus is one of the most prevalent chronic diseases. Previous studies have shown differences in glucose metabolism between males and females. Moreover, difficulties in medication adherence have been reported in females with type 2 diabetes. These observations are believed to be caused by fluctuations in sex hormone concentrations during the menstrual cycle. Furthermore, gut microbiota is linked to female host metabolism and sex hormone production. Understanding the interactions between fluctuating hormone concentrations during the menstrual cycle, gut microbiota, and glucose metabolism in humans is significant because of the increasing prevalence of diabetes and the consequent need to expand preventive efforts. A literature search was performed to determine and summarize the existing evidence, deduce future research needs to maintain female health, and investigate the relationship between the physiological menstrual cycle and glucose metabolism. Studies from 1967 to 2020 have already examined the relationship between variations during the menstrual cycle and glucose metabolism in healthy female subjects using an oral-glucose tolerance test or intravenous glucose tolerance test. However, the overall number of studies is rather small and the results are contradictory, as some studies detected differences in glucose concentrations depending on the different cycle phases, whereas others did not. Some studies reported lower glucose levels in the follicular phase than in the luteal phase, whereas another study detected the opposite. Data on gut microbiota in relation to the menstrual cycle are limited. Conflicting results exist when examining the effect of hormonal contraceptives on the gut microbiota and changes in the course of the menstrual cycle. The results indicate that the menstrual cycle, especially fluctuating sex hormones, might impact the gut microbiota composition.The menstrual cycle may affect the gut microbiota composition and glucose metabolism. These results indicate that glucose tolerance may be the greatest in the follicular phase; however, further well-conducted studies are needed to support this assumption.


Assuntos
Microbioma Gastrointestinal , Hormônios Esteroides Gonadais , Ciclo Menstrual , Humanos , Microbioma Gastrointestinal/fisiologia , Feminino , Ciclo Menstrual/fisiologia , Ciclo Menstrual/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Hormônios Esteroides Gonadais/sangue , Glucose/metabolismo , Glicemia/metabolismo
2.
J Thromb Haemost ; 22(3): 805-817, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38029856

RESUMO

BACKGROUND: Platelets play a key role in hemostasis, inflammation, and cardiovascular diseases. Platelet reactivity is highly variable between individuals. The drivers of this variability in populations from Sub-Saharan Africa remain largely unknown. OBJECTIVES: We aimed to investigate the nongenetic and genetic determinants of platelet reactivity in healthy adults living in a rapidly urbanizing area in Northern Tanzania. METHODS: Platelet activation and reactivity were measured by platelet P-selectin expression and the binding of fibrinogen in unstimulated blood and after ex vivo stimulation with adenosine diphosphate and PAR-1 and PAR-4 ligands. We then analyzed the associations of platelet parameters with host genetic and nongenetic factors, environmental factors, plasma inflammatory markers, and plasma metabolites. RESULTS: Only a few associations were found between platelet reactivity parameters and plasma inflammatory markers and nongenetic host and environmental factors. In contrast, untargeted plasma metabolomics revealed a large number of associations with food-derived metabolites, including phytochemicals that were previously reported to inhibit platelet reactivity. Genome-wide single-nucleotide polymorphism genotyping identified 2 novel single-nucleotide polymorphisms (rs903650 and rs4789332) that were associated with platelet reactivity at the genome-wide level (P < 5 × 10-8) as well as a number of variants in the PAR4 gene (F2RL3) that were associated with PAR4-induced reactivity. CONCLUSION: Our study uncovered factors that determine variation in platelet reactivity in a population in East Africa that is rapidly transitioning to an urban lifestyle, including the importance of genetic ancestry and the gradual abandoning of the traditional East African diet.


Assuntos
Plaquetas , Agregação Plaquetária , Adulto , Humanos , Agregação Plaquetária/fisiologia , Tanzânia , Plaquetas/metabolismo , Ativação Plaquetária , Receptor PAR-1/metabolismo
3.
Elife ; 122023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37555575

RESUMO

Non-communicable diseases (NCDs) are rising rapidly in urbanizing populations in sub-Saharan Africa. Assessment of inflammatory and metabolic characteristics of a urbanizing African population and the comparison with populations outside Africa could provide insight in the pathophysiology of the rapidly increasing epidemic of NCDs, including the role of environmental and dietary changes. Using a proteomic plasma profiling approach comprising 92 inflammation-related molecules, we examined differences in the inflammatory proteome in healthy Tanzanian and healthy Dutch adults. We show that healthy Tanzanians display a pro-inflammatory phenotype compared to Dutch subjects, with enhanced activity of the Wnt/ß-catenin signalling pathway and higher concentrations of different metabolic regulators such as 4E-BP1 and fibroblast growth factor 21. Among the Tanzanian volunteers, food-derived metabolites were identified as an important driver of variation in inflammation-related molecules, emphasizing the potential importance of lifestyle changes. These findings endorse the importance of the current dietary transition and the inclusion of underrepresented populations in systems immunology studies.


Assuntos
População da África Oriental , População Europeia , Inflamação , Proteoma , Humanos , África Subsaariana/epidemiologia , Doenças não Transmissíveis/epidemiologia , Proteômica
4.
Cell Rep ; 42(6): 112525, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37243592

RESUMO

Systemic inflammation is established as part of late-stage severe lung disease, but molecular, functional, and phenotypic changes in peripheral immune cells in early disease stages remain ill defined. Chronic obstructive pulmonary disease (COPD) is a major respiratory disease characterized by small-airway inflammation, emphysema, and severe breathing difficulties. Using single-cell analyses we demonstrate that blood neutrophils are already increased in early-stage COPD, and changes in molecular and functional neutrophil states correlate with lung function decline. Assessing neutrophils and their bone marrow precursors in a murine cigarette smoke exposure model identified similar molecular changes in blood neutrophils and precursor populations that also occur in the blood and lung. Our study shows that systemic molecular alterations in neutrophils and their precursors are part of early-stage COPD, a finding to be further explored for potential therapeutic targets and biomarkers for early diagnosis and patient stratification.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Humanos , Animais , Camundongos , Neutrófilos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Pulmão , Inflamação
6.
Cell Rep Med ; 3(6): 100652, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35675822

RESUMO

Disease recovery dynamics are often difficult to assess, as patients display heterogeneous recovery courses. To model recovery dynamics, exemplified by severe COVID-19, we apply a computational scheme on longitudinally sampled blood transcriptomes, generating recovery states, which we then link to cellular and molecular mechanisms, presenting a framework for studying the kinetics of recovery compared with non-recovery over time and long-term effects of the disease. Specifically, a decrease in mature neutrophils is the strongest cellular effect during recovery, with direct implications on disease outcome. Furthermore, we present strong indications for global regulatory changes in gene programs, decoupled from cell compositional changes, including an early rise in T cell activation and differentiation, resulting in immune rebalancing between interferon and NF-κB activity and restoration of cell homeostasis. Overall, we present a clinically relevant computational framework for modeling disease recovery, paving the way for future studies of the recovery dynamics in other diseases and tissues.


Assuntos
COVID-19 , NF-kappa B , Diferenciação Celular , Humanos , Interferons/metabolismo , NF-kappa B/genética , Neutrófilos/metabolismo , Transdução de Sinais
7.
Nutrients ; 14(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35565752

RESUMO

(1) Background: Sub-Saharan Africa is experiencing the fastest urbanization worldwide. People in rural areas still have a traditional and rural lifestyle, whereas the Westernization of diet and lifestyle is already evident in urban areas. This study describes dietary habits of families in Burkina Faso living at different levels of urbanization. (2) Methods: Data on lifestyle, socio-economic conditions, health status and anthropometry were collected from 30 families living in rural villages, a small town and the capital city. A food frequency questionnaire and a 24 h recall diary were used to estimate dietary habits and macronutrients intake. (3) Results: The urban cohort showed a more diversified diet, with a higher intake of animal protein and, especially in children, a higher consumption of simple sugars. Fiber intake was significantly higher in the rural and semi-urbanized cohorts. As expected, overweight and obesity gradually increased with the level of urbanization. In semi-urbanized and urban families, we observed coexistence of under- and over-nutrition, whereas in rural families, a portion of children were wasted and stunted, and adults were underweight. (4) Conclusions: These three cohorts represent a model of the effect on diet of rural-to-urban migration. Rural diet and traditional habits are replaced by a Western-oriented diet when families move to urbanized areas. This dietary transition and increased socio-economic status in newly developing urban areas have a major impact on disease epidemiology, resembling the past evolution in Western countries.


Assuntos
Status Econômico , Urbanização , Burkina Faso/epidemiologia , Comportamento Alimentar , Humanos , População Rural , População Urbana
8.
J Thromb Haemost ; 20(5): 1089-1105, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35102686

RESUMO

BACKGROUND: Geographic variability in coagulation across populations and their determinants are poorly understood. OBJECTIVE: To compare thrombin (TG) and plasmin (PG) generation parameters between healthy Tanzanian and Dutch individuals, and to study associations with inflammation and different genetic, host and environmental factors. METHODS: TG and PG parameters were measured in 313 Tanzanians of African descent living in Tanzania and 392 Dutch of European descent living in the Netherlands and related to results of a dietary questionnaire, circulating inflammatory markers, genotyping, and plasma metabolomics. RESULTS: Tanzanians exhibited an enhanced TG and PG capacity, compared to Dutch participants. A higher proportion of Tanzanians had a TG value in the upper quartile with a PG value in the lower/middle quartile, suggesting a relative pro-coagulant state. Tanzanians also displayed an increased normalized thrombomodulin sensitivity ratio, suggesting reduced sensitivity to protein C. In Tanzanians, PG parameters (lag time and TTP) were associated with seasonality and food-derived plasma metabolites. The Tanzanians had higher concentrations of pro-inflammatory cytokines, which correlated strongly with TG and PG parameters. There was limited overlap in genetic variation associated with TG and PG parameters between the two cohorts. Pathway analysis of genetic variants in the Tanzanian cohort revealed multiple immune pathways that were enriched with TG and PG traits, confirming the importance of co-regulation between coagulation and inflammation. CONCLUSIONS: Tanzanians have an enhanced TG and PG potential compared to Dutch individuals, which may relate to differences in inflammation, genetics and diet. These observations highlight the importance of better understanding of the geographic variability in coagulation across populations.


Assuntos
Fibrinolisina , Trombina , Adulto , População Negra , Coagulação Sanguínea/genética , Testes de Coagulação Sanguínea , Fibrinolisina/metabolismo , Humanos , Inflamação/genética , Países Baixos , Tanzânia , Trombina/metabolismo , População Branca
9.
Nat Commun ; 12(1): 7322, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34916498

RESUMO

Blastocyst-derived stem cell lines were shown to self-organize into embryo-like structures in 3D cell culture environments. Here, we provide evidence that embryo-like structures can be generated solely based on transcription factor-mediated reprogramming of embryonic stem cells in a simple 3D co-culture system. Embryonic stem cells in these cultures self-organize into elongated, compartmentalized embryo-like structures reflecting aspects of the inner regions of the early post-implantation embryo. Single-cell RNA-sequencing reveals transcriptional profiles resembling epiblast, primitive-/visceral endoderm, and extraembryonic ectoderm of early murine embryos around E4.5-E5.5. In this stem cell-based embryo model, progression from rosette formation to lumenogenesis accompanied by progression from naïve- to primed pluripotency was observed within Epi-like cells. Additionally, lineage specification of primordial germ cells and distal/anterior visceral endoderm-like cells was observed in epiblast- or visceral endoderm-like compartments, respectively. The system presented in this study allows for fast and reproducible generation of embryo-like structures, providing an additional tool to study aspects of early embryogenesis.


Assuntos
Corpos Embrioides/citologia , Desenvolvimento Embrionário , Células-Tronco Embrionárias/citologia , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Técnicas de Cultura de Células em Três Dimensões , Reprogramação Celular , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Corpos Embrioides/metabolismo , Células-Tronco Embrionárias/metabolismo , Endoderma/embriologia , Endoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , RNA-Seq
10.
Nat Immunol ; 22(3): 287-300, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33574617

RESUMO

Sub-Saharan Africa currently experiences an unprecedented wave of urbanization, which has important consequences for health and disease patterns. This study aimed to investigate and integrate the immune and metabolic consequences of rural or urban lifestyles and the role of nutritional changes associated with urban living. In a cohort of 323 healthy Tanzanians, urban as compared to rural living was associated with a pro-inflammatory immune phenotype, both at the transcript and protein levels. We identified different food-derived and endogenous circulating metabolites accounting for these differences. Serum from urban dwellers induced reprogramming of innate immune cells with higher tumor necrosis factor production upon microbial re-stimulation in an in vitro model of trained immunity. These data demonstrate important shifts toward an inflammatory phenotype associated with an urban lifestyle and provide new insights into the underlying dietary and metabolic factors, which may affect disease epidemiology in sub-Sahara African countries.


Assuntos
Citocinas/sangue , Dieta Saudável , Metabolismo Energético , Imunidade Inata , Mediadores da Inflamação/sangue , Saúde da População Rural , Saúde da População Urbana , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Citocinas/genética , Metabolismo Energético/genética , Feminino , Humanos , Imunidade Inata/genética , Masculino , Metaboloma , Pessoa de Meia-Idade , Estado Nutricional , Valor Nutritivo , Comportamento de Redução do Risco , Estações do Ano , Tanzânia , Transcriptoma , Fator de Necrose Tumoral alfa/sangue , Urbanização , Adulto Jovem
11.
Genome Med ; 13(1): 7, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441124

RESUMO

BACKGROUND: The SARS-CoV-2 pandemic is currently leading to increasing numbers of COVID-19 patients all over the world. Clinical presentations range from asymptomatic, mild respiratory tract infection, to severe cases with acute respiratory distress syndrome, respiratory failure, and death. Reports on a dysregulated immune system in the severe cases call for a better characterization and understanding of the changes in the immune system. METHODS: In order to dissect COVID-19-driven immune host responses, we performed RNA-seq of whole blood cell transcriptomes and granulocyte preparations from mild and severe COVID-19 patients and analyzed the data using a combination of conventional and data-driven co-expression analysis. Additionally, publicly available data was used to show the distinction from COVID-19 to other diseases. Reverse drug target prediction was used to identify known or novel drug candidates based on finding from data-driven findings. RESULTS: Here, we profiled whole blood transcriptomes of 39 COVID-19 patients and 10 control donors enabling a data-driven stratification based on molecular phenotype. Neutrophil activation-associated signatures were prominently enriched in severe patient groups, which was corroborated in whole blood transcriptomes from an independent second cohort of 30 as well as in granulocyte samples from a third cohort of 16 COVID-19 patients (44 samples). Comparison of COVID-19 blood transcriptomes with those of a collection of over 3100 samples derived from 12 different viral infections, inflammatory diseases, and independent control samples revealed highly specific transcriptome signatures for COVID-19. Further, stratified transcriptomes predicted patient subgroup-specific drug candidates targeting the dysregulated systemic immune response of the host. CONCLUSIONS: Our study provides novel insights in the distinct molecular subgroups or phenotypes that are not simply explained by clinical parameters. We show that whole blood transcriptomes are extremely informative for COVID-19 since they capture granulocytes which are major drivers of disease severity.


Assuntos
COVID-19/patologia , Neutrófilos/metabolismo , Transcriptoma , Antivirais/uso terapêutico , COVID-19/virologia , Estudos de Casos e Controles , Regulação para Baixo , Reposicionamento de Medicamentos , Humanos , Neutrófilos/citologia , Neutrófilos/imunologia , Fenótipo , Análise de Componente Principal , RNA/sangue , RNA/química , RNA/metabolismo , Análise de Sequência de RNA , Índice de Gravidade de Doença , Regulação para Cima , Tratamento Farmacológico da COVID-19
12.
Cell ; 182(6): 1419-1440.e23, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32810438

RESUMO

Coronavirus disease 2019 (COVID-19) is a mild to moderate respiratory tract infection, however, a subset of patients progress to severe disease and respiratory failure. The mechanism of protective immunity in mild forms and the pathogenesis of severe COVID-19 associated with increased neutrophil counts and dysregulated immune responses remain unclear. In a dual-center, two-cohort study, we combined single-cell RNA-sequencing and single-cell proteomics of whole-blood and peripheral-blood mononuclear cells to determine changes in immune cell composition and activation in mild versus severe COVID-19 (242 samples from 109 individuals) over time. HLA-DRhiCD11chi inflammatory monocytes with an interferon-stimulated gene signature were elevated in mild COVID-19. Severe COVID-19 was marked by occurrence of neutrophil precursors, as evidence of emergency myelopoiesis, dysfunctional mature neutrophils, and HLA-DRlo monocytes. Our study provides detailed insights into the systemic immune response to SARS-CoV-2 infection and reveals profound alterations in the myeloid cell compartment associated with severe COVID-19.


Assuntos
Infecções por Coronavirus/imunologia , Células Mieloides/imunologia , Mielopoese , Pneumonia Viral/imunologia , Adulto , Idoso , Antígenos CD11/genética , Antígenos CD11/metabolismo , COVID-19 , Células Cultivadas , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Feminino , Antígenos HLA-DR/genética , Antígenos HLA-DR/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Células Mieloides/citologia , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/patologia , Proteoma/genética , Proteoma/metabolismo , Proteômica , Análise de Célula Única
13.
Diabetes ; 69(11): 2310-2323, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32732304

RESUMO

Elevated expression of E2F1 in adipocyte fraction of human visceral adipose tissue (hVAT) associates with a poor cardiometabolic profile. We hypothesized that beyond directly activating autophagy and MAP3K5 (ASK)-MAP kinase signaling, E2F1 governs a distinct transcriptome that contributes to adipose tissue and metabolic dysfunction in obesity. We performed RNA sequencing of hVAT samples from age-, sex-, and BMI-matched patients, all obese, whose visceral E2F1 protein expression was either high (E2F1high) or low (E2F1low). Tumor necrosis factor superfamily (TNFSF) members, including TRAIL (TNFSF10), TL1A (TNFSF15), and their receptors, were enriched in E2F1high While TRAIL was equally expressed in adipocytes and stromal vascular fraction (SVF), TL1A was mainly expressed in SVF, and TRAIL-induced TL1A was attributed to CD4+ and CD8+ subclasses of hVAT T cells. In human adipocytes, TL1A enhanced basal and impaired insulin-inhibitable lipolysis and altered adipokine secretion, and in human macrophages it induced foam cell biogenesis and M1 polarization. Two independent human cohorts confirmed associations between TL1A and TRAIL expression in hVAT and higher leptin and IL6 serum concentrations, diabetes status, and hVAT-macrophage lipid content. Jointly, we propose an intra-adipose tissue E2F1-associated TNFSF paracrine loop engaging lymphocytes, macrophages, and adipocytes, ultimately contributing to adipose tissue dysfunction in obesity.


Assuntos
Adipócitos/fisiologia , Fator de Transcrição E2F1/metabolismo , Linfócitos/fisiologia , Macrófagos/fisiologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Tecido Adiposo/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Técnicas de Cocultura , Fator de Transcrição E2F1/genética , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Comunicação Parácrina , Ligante Indutor de Apoptose Relacionado a TNF/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Adulto Jovem
14.
Cells ; 9(6)2020 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-32575785

RESUMO

The identification of human obesity sub-types may improve the clinical management of patients with obesity and uncover previously unrecognized obesity mechanisms. Here, we hypothesized that adipose tissue (AT) mast cells (MC) estimation could be a mark for human obesity sub-phenotyping beyond current clinical-based stratifications, both cross-sectionally and prospectively. We estimated MC accumulation using immunohistochemistry and gene expression in abdominal visceral AT (VAT) and subcutaneous (SAT) in a human cohort of 65 persons with obesity who underwent elective abdominal (mainly bariatric) surgery, and we validated key results in two clinically similar, independent cohorts (n = 33, n = 56). AT-MC were readily detectable by immunostaining for either c-kit or tryptase and by assessing the gene expression of KIT (KIT Proto-Oncogene, Receptor Tyrosine Kinase), TPSB2 (tryptase beta 2), and CMA1 (chymase 1). Participants were characterized as VAT-MClow if the expression of both CMA1 and TPSB2 was below the median. Higher expressers of MC genes (MChigh) were metabolically healthier (lower fasting glucose and glycated hemoglobin, with higher pancreatic beta cell reserve (HOMA-ß), and lower triglycerides and alkaline-phosphatase) than people with low expression (MClow). Prospectively, higher MC accumulation in VAT or SAT obtained during surgery predicted greater postoperative weight-loss response to bariatric surgery. Jointly, high AT-MC accumulation may be used to clinically define obesity sub-phenotypes, which are associated with a "healthier" cardiometabolic risk profile and a better weight-loss response to bariatric surgery.


Assuntos
Tecido Adiposo/metabolismo , Mastócitos/metabolismo , Obesidade/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Proto-Oncogene Mas
15.
Cell Mol Life Sci ; 77(3): 415-432, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31768606

RESUMO

Heterogeneity is universally observed in all natural systems and across multiple scales. Understanding population heterogeneity is an intriguing and attractive topic of research in different disciplines, including microbiology and immunology. Microbes and mammalian immune cells present obviously rather different system-specific biological features. Nevertheless, as typically occurs in science, similar methods can be used to study both types of cells. This is particularly true for mathematical modeling, in which key features of a system are translated into algorithms to challenge our mechanistic understanding of the underlying biology. In this review, we first present a broad overview of the experimental developments that allowed observing heterogeneity at the single cell level. We then highlight how this "data revolution" requires the parallel advancement of algorithms and computing infrastructure for data processing and analysis, and finally present representative examples of computational models of population heterogeneity, from microbial communities to immune response in cells.


Assuntos
Imunidade/fisiologia , Microbiota/fisiologia , Algoritmos , Animais , Simulação por Computador , Humanos , Modelos Teóricos
16.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1864(12): 158527, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31520777

RESUMO

The regulation of lipid droplet (LD) dynamics by autophagy in naïve macrophages is complex: Inhibiting autophagosome initiation steps attenuates oleic acid (OA) induced LD (OA-LD) biogenesis, whereas interfering with later-autophagosome maturation/lysosomal steps accelerates OA-LD biogenesis rate, but not OA-LD degradation. Here we hypothesized that regulation of macrophage lipid handling by autophagy may be lipid-substrate and activation-state-specific. Using automated quantitative live-cell imaging, initial LD biogenesis rate was ~30% slower when the lipid source was acetylated low density lipoprotein (acLDL) compared to OA. Yet, both were similarly affected by triacsin-C, an inhibitor of acyl-CoA synthase, which inhibited, and etomoxir, an inhibitor of acylcarnitine palmitoyl transferase (fatty acid oxidation), which augmented, LD biogenesis rates. An autophagy inducing peptide, Tat-Beclin1, enhanced the degradation, and inhibited (by 37%) the biogenesis of acLDL induced LD (acLDL-LD). Yet, Tat-Beclin1 increased OA-LD biogenesis rate by 70%. When macrophages were pre-activated with LPS + INFG they exhibited increased autophagosome number and area, and reduced BECN1 and ATG14 protein levels, which associated with a markedly attenuated autophagic flux. Concomitantly, OA-LD and acLDL-LD biogenesis rates increased 3 and 7.4-fold, respectively, but could not be further modulated by Tat-Beclin1, as observed in non-activated/naïve macrophages. We propose that macrophage autophagy, and/or components of its machinery, differentially regulate LD/foam-cell biogenesis depending on the lipid-source, and that inflammatory activation uncouples autophagy from LD biogenesis.


Assuntos
Autofagia , Lipoproteínas LDL/imunologia , Ativação de Macrófagos , Macrófagos/imunologia , Ácido Oleico/imunologia , Animais , Inflamação/imunologia , Macrófagos/citologia , Camundongos , Células RAW 264.7
17.
J Toxicol Environ Health A ; 82(9): 564-576, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242808

RESUMO

The effects of particulate matter (PM) air pollution on adipose tissue have mainly been studied in animal models. The aim of this study was to examine the potential associations between PM exposure and 25 cellular markers in human omental (OM) and subcutaneous (SC) adipose tissue. The PM exposure assessments for both PM2.5 (PM <2.5 µm in diameter) and PM10 (<10 µm) were based upon a novel hybrid satellite-based spatio-temporally resolved model. We calculated the PM exposure above the background threshold for 1 week (acute phase), 3 and 6 months (intermediate phase), and 1 year (chronic phase) prior to tissue harvesting and tested the associations with adipose cell metabolic effects using multiple linear regressions and heat maps strategy. Chemokine levels were found to increase after acute and intermediate exposure duration to PM10. The levels of stress signaling biomarkers in the SC and OM tissues rose after acute exposure to PM10 and PM2.5. Macrophage and leucocyte counts were associated with severity of PM exposure in all three duration groups. Adipocyte diameter decreased in all exposure periods. Our results provide evidence for significant contribution of air pollutants exposure to adipose tissue inflammation as well as for pathophysiological mechanisms of metabolic dysregulation that may be involved in the observed responses.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Material Particulado/efeitos adversos , Adulto , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
18.
Eur J Immunol ; 49(1): 19-29, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30407631

RESUMO

The involvement of macrophages in the pathogenesis of obesity has been recognized since 2003. Early studies mostly focused on the role of macrophages in adipose tissue (AT) and in obesity-associated chronic low-grade inflammation. Lately, AT macrophages were shown to undergo intrinsic metabolic changes that affect their immune function (i.e., immunometabolism), corresponding to their unique properties along the range of pro- versus anti-inflammatory activity. In parallel, recent studies in mice revealed critical neuronal-macrophage interactions, both in the CNS and in peripheral tissues, including in white and brown AT. These intercellular activities impinge on energy and metabolic homeostasis, partially by also engaging adipocytes in a neuronal-macrophage-adipocyte ménage à trois. Finally, neuropeptides (NP), such as NPY and appetite-reducing NPFF, may prove as mediators in such intercellular network. In this concise review, we highlight some of these recent insights on adipose macrophage immunometabolism, as well as central and peripheral neuronal-macrophage interactions with emphasis on their impact on adipocyte biology and whole-body metabolism. We also discuss the expanding view on the role of the NP, NPY and NPFF, in obesity.


Assuntos
Tecido Adiposo/fisiologia , Inflamação/imunologia , Macrófagos/fisiologia , Neurônios/fisiologia , Obesidade/imunologia , Animais , Comunicação Celular , Sistema Nervoso Central , Humanos , Neuropeptídeos/metabolismo
19.
Diabetologia ; 60(10): 1892-1902, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28733906

RESUMO

AIMS/HYPOTHESIS: Not all people with type 2 diabetes who undergo bariatric surgery achieve diabetes remission. Thus it is critical to develop methods for predicting outcomes that are applicable for clinical practice. The DiaRem score is relevant for predicting diabetes remission post-Roux-en-Y gastric bypass (RYGB), but it is not accurate for all individuals across the entire spectrum of scores. We aimed to develop an improved scoring system for predicting diabetes remission following RYGB (the Advanced-DiaRem [Ad-DiaRem]). METHODS: We used a retrospective French cohort (n = 1866) that included 352 individuals with type 2 diabetes followed for 1 year post-RYGB. We developed the Ad-DiaRem in a test cohort (n = 213) and examined its accuracy in independent cohorts from France (n = 134) and Israel (n = 99). RESULTS: Adding two clinical variables (diabetes duration and number of glucose-lowering agents) to the original DiaRem and modifying the penalties for each category led to improved predictive performance for Ad-DiaRem. Ad-DiaRem displayed improved area under the receiver operating characteristic curve and predictive accuracy compared with DiaRem (0.911 vs 0.856 and 0.841 vs 0.789, respectively; p = 0.03); thus correcting classification for 8% of those initially misclassified with DiaRem. With Ad-DiaRem, there were also fewer misclassifications of individuals with mid-range scores. This improved predictive performance was confirmed in independent cohorts. CONCLUSIONS/INTERPRETATION: We propose the Ad-DiaRem, which includes two additional clinical variables, as an optimised tool with improved accuracy to predict diabetes remission 1 year post-RYGB. This tool might be helpful for personalised management of individuals with diabetes when considering bariatric surgery in routine care, ultimately contributing to precision medicine.


Assuntos
Diabetes Mellitus Tipo 2/cirurgia , Derivação Gástrica , Obesidade Mórbida/cirurgia , Adiposidade/fisiologia , Adulto , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Feminino , França , Humanos , Resistência à Insulina/fisiologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/sangue , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento
20.
J Endocrinol ; 233(3): 293-305, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28360082

RESUMO

Adipose tissue inflammation and dysfunction are considered central in the pathogenesis of obesity-related dysmetabolism, but their role in the rapid metabolic recovery upon obesity reversal is less well defined. We hypothesized that changes in adipose tissue endocrine and paracrine mechanisms may support the rapid improvement of obesity-induced impairment in cellular lipid handling. C57Bl-6J mice were fed ad libitum either normal chow (NC) or high-fat diet (HFF) for 10 weeks. A dietary obesity reversal group was fed HFF for 8 weeks and then switched to NC for 2 weeks (HFF→NC). Whole-body glucose homeostasis rapidly nearly normalized in the HFF→NC mice (fasting glucose and insulin fully normalized, glucose and insulin tolerance tests reversed 82% to the NC group levels). During 2 weeks of the dietary reversal, the liver was significantly cleared from ectopic fat, and functionally, glucose production from pyruvate, alanine or fructose was normalized. In contrast, adipose tissue inflammation (macrophage infiltration and polarization) largely remained as in HFF, though obesity-induced adipose tissue macrophage lipid accumulation decreased by ~50%, and adipose tissue MAP kinase hyperactivation was reversed. Ex vivo, mild changes in adipose tissue adipocytokine secretion profile were noted. These corresponded to partial or full reversal of the excess cellular lipid droplet accumulation induced by HFF adipose tissue conditioned media in hepatoma or macrophage cells, respectively. We propose that early after initiating reversal of nutritional obesity, rapid metabolic normalization largely precedes resolution of adipose tissue inflammation. Nevertheless, we demonstrate a hitherto unrecognized contribution of adipose tissue to the rapid improvement in lipid handling by the liver and by macrophages.


Assuntos
Tecido Adiposo/fisiologia , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Macrófagos/fisiologia , Obesidade/metabolismo , Animais , Regulação da Expressão Gênica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Redução de Peso
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