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The transcription factor IRF8 is essential for the development of monocytes and dendritic cells (DCs), whereas it inhibits neutrophilic differentiation. It is unclear how Irf8 expression is regulated and how this single transcription factor supports the generation of both monocytes and DCs. Here, we identified a RUNX-CBFß-driven enhancer 56 kb downstream of the Irf8 transcription start site. Deletion of this enhancer in vivo significantly decreased Irf8 expression throughout the myeloid lineage from the progenitor stages, thus resulting in loss of common DC progenitors and overproduction of Ly6C+ monocytes. We demonstrated that high, low or null expression of IRF8 in hematopoietic progenitor cells promotes differentiation toward type 1 conventional DCs, Ly6C+ monocytes or neutrophils, respectively, via epigenetic regulation of distinct sets of enhancers in cooperation with other transcription factors. Our results illustrate the mechanism through which IRF8 controls the lineage choice in a dose-dependent manner within the myeloid cell system.
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Linhagem da Célula , Subunidades alfa de Fatores de Ligação ao Core/metabolismo , Subunidade beta de Fator de Ligação ao Core/metabolismo , Células Dendríticas/metabolismo , Elementos Facilitadores Genéticos , Fatores Reguladores de Interferon/metabolismo , Monócitos/metabolismo , Células Progenitoras Mieloides/metabolismo , Animais , Antígenos Ly/genética , Antígenos Ly/metabolismo , Células da Medula Óssea , Células Cultivadas , Subunidades alfa de Fatores de Ligação ao Core/genética , Subunidade beta de Fator de Ligação ao Core/genética , Células Dendríticas/imunologia , Epigênese Genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Monócitos/imunologia , Células Progenitoras Mieloides/imunologia , Fenótipo , Transdução de SinaisRESUMO
Interferon regulatory factor-5 (IRF5), a transcription factor critical for the induction of innate immune responses, contributes to the pathogenesis of the autoimmune disease systemic lupus erythematosus (SLE) in humans and mice. Lyn, a Src family kinase, is also implicated in human SLE, and Lyn-deficient mice develop an SLE-like disease. Here, we found that Lyn physically interacted with IRF5 to inhibit ubiquitination and phosphorylation of IRF5 in the TLR-MyD88 pathway, thereby suppressing the transcriptional activity of IRF5 in a manner independent of Lyn's kinase activity. Conversely, Lyn did not inhibit NF-κB signaling, another major branch downstream of MyD88. Monoallelic deletion of Irf5 alleviated the hyperproduction of cytokines in TLR-stimulated Lyn(-/-) dendritic cells and the development of SLE-like symptoms in Lyn(-/-) mice. Our results reveal a role for Lyn as a specific suppressor of the TLR-MyD88-IRF5 pathway and illustrate the importance of fine-tuning IRF5 activity for the maintenance of immune homeostasis.
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Autoimunidade , Células Dendríticas/imunologia , Fatores Reguladores de Interferon/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Quinases da Família src/metabolismo , Animais , Células Cultivadas , Citocinas/metabolismo , Humanos , Tolerância Imunológica , Imunidade Inata , Fatores Reguladores de Interferon/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Fosforilação , Ligação Proteica , Transdução de Sinais , Receptores Toll-Like/metabolismo , Ativação Transcricional , Ubiquitinação , Quinases da Família src/genéticaRESUMO
Classical dendritic cells (cDCs) are essential for immune responses and differentiate from hematopoietic stem cells via intermediate progenitors, such as monocyte-DC progenitors (MDPs) and common DC progenitors (CDPs). Upon infection, cDCs are activated and rapidly express host defense-related genes, such as those encoding cytokines and chemokines. Chromatin structures, including nuclear compartments and topologically associating domains (TADs), have been implicated in gene regulation. However, the extent and dynamics of their reorganization during cDC development and activation remain unknown. In this study, we comprehensively determined higher-order chromatin structures by Hi-C in DC progenitors and cDC subpopulations. During cDC differentiation, chromatin activation was initially induced at the MDP stage. Subsequently, a shift from inactive to active nuclear compartments occurred at the cDC gene loci in CDPs, which was followed by increased intra-TAD interactions and loop formation. Mechanistically, the transcription factor IRF8, indispensable for cDC differentiation, mediated chromatin activation and changes into the active compartments in DC progenitors, thereby possibly leading to cDC-specific gene induction. Using an infection model, we found that the chromatin structures of host defense-related gene loci were preestablished in unstimulated cDCs, indicating that the formation of higher-order chromatin structures prior to infection may contribute to the rapid responses to pathogens. Overall, these results suggest that chromatin structure reorganization is closely related to the establishment of cDC-specific gene expression and immune functions. This study advances the fundamental understanding of chromatin reorganization in cDC differentiation and activation.
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Montagem e Desmontagem da Cromatina , Células Dendríticas , Células-Tronco Hematopoéticas , Animais , Diferenciação Celular/genética , Cromatina/genética , Cromatina/metabolismo , Células Dendríticas/citologia , Regulação da Expressão Gênica , CamundongosRESUMO
The concept of local formation of angiotensin II in the kidney has changed over the last 10-15 years. Local synthesis of angiotensinogen in the proximal tubule has been proposed, combined with prorenin synthesis in the collecting duct. Binding of prorenin via the so-called (pro)renin receptor has been introduced, as well as megalin-mediated uptake of filtered plasma-derived renin-angiotensin system (RAS) components. Moreover, angiotensin metabolites other than angiotensin II [notably angiotensin-(1-7)] exist, and angiotensins exert their effects via three different receptors, of which angiotensin II type 2 and Mas receptors are considered renoprotective, possibly in a sex-specific manner, whereas angiotensin II type 1 (AT1) receptors are believed to be deleterious. Additionally, internalized angiotensin II may stimulate intracellular receptors. Angiotensin-converting enzyme 2 (ACE2) not only generates angiotensin-(1-7) but also acts as coronavirus receptor. Multiple, if not all, cardiovascular diseases involve the kidney RAS, with renal AT1 receptors often being claimed to exert a crucial role. Urinary RAS component levels, depending on filtration, reabsorption, and local release, are believed to reflect renal RAS activity. Finally, both existing drugs (RAS inhibitors, cyclooxygenase inhibitors) and novel drugs (angiotensin receptor/neprilysin inhibitors, sodium-glucose cotransporter-2 inhibitors, soluble ACE2) affect renal angiotensin formation, thereby displaying cardiovascular efficacy. Particular in the case of the latter three, an important question is to what degree they induce renoprotection (e.g., in a renal RAS-dependent manner). This review provides a unifying view, explaining not only how kidney angiotensin formation occurs and how it is affected by drugs but also why drugs are renoprotective when altering the renal RAS. SIGNIFICANCE STATEMENT: Angiotensin formation in the kidney is widely accepted but little understood, and multiple, often contrasting concepts have been put forward over the last two decades. This paper offers a unifying view, simultaneously explaining how existing and novel drugs exert renoprotection by interfering with kidney angiotensin formation.
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Angiotensinogênio , Doenças Cardiovasculares , Feminino , Humanos , Masculino , Angiotensina II/metabolismo , Enzima de Conversão de Angiotensina 2 , Angiotensinogênio/metabolismo , Doenças Cardiovasculares/metabolismo , Sistemas de Liberação de Medicamentos , Rim/irrigação sanguínea , Rim/metabolismo , Renina/metabolismo , Sistema Renina-Angiotensina , Inibidores do Transportador 2 de Sódio-Glicose/metabolismoRESUMO
Microglia are the principal phagocytes that clear cell debris in the central nervous system (CNS). This raises the question, which cells remove cell debris when microglial phagocytic activity is impaired. We addressed this question using Siglechdtr mice, which enable highly specific ablation of microglia. Non-microglial mononuclear phagocytes, such as CNS-associated macrophages and circulating inflammatory monocytes, did not clear microglial debris. Instead, astrocytes were activated, exhibited a pro-inflammatory gene expression profile, and extended their processes to engulf microglial debris. This astrocytic phagocytosis was also observed in Irf8-deficient mice, in which microglia were present but dysfunctional. RNA-seq demonstrated that even in a healthy CNS, astrocytes express TAM phagocytic receptors, which were the main astrocytic phagocytic receptors for cell debris in the above experiments, indicating that astrocytes stand by in case of microglial impairment. This compensatory mechanism may be important for the maintenance or prolongation of a healthy CNS.
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Astrócitos/fisiologia , Microglia/metabolismo , Fagocitose/fisiologia , Animais , Astrócitos/citologia , Encéfalo , Sistema Nervoso Central/fisiologia , Modelos Animais de Doenças , Feminino , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/genética , Masculino , Camundongos , Camundongos Knockout , Microglia/ultraestrutura , Fagocitose/genéticaRESUMO
Beta-adrenergic receptors (ß-AR) are expressed on the membranes of various cell types and their activation affects body water balance by modulating renal sodium and water excretion, cardiovascular function and metabolic processes. However, ß-AR-associated body fluid imbalance has not been well characterised. In the present study, we hypothesized that chronic ß-AR stimulation increases electrolyte and water content at the tissue level. We evaluated the effects of isoproterenol, a non-selective ß-AR agonist, on electrolyte and water balance at the tissue level. Continuous isoproterenol administration for 14 days induced cardiac hypertrophy, associated with sodium-driven water retention in the heart, increased the total body sodium, potassium and water contents at the tissue level, and increased the water intake and blood pressure of the mice. There was greater urine output in response to the isoproterenol-induced body water retention. These isoproterenol-induced changes were reduced by propranolol, a non-selective beta-receptor inhibitor. Isoproterenol-treated mice even without excessive water intake had higher total body electrolyte and water contents, and this tissue water retention was associated with lower dry body mass, suggesting that ß-AR stimulation in the absence of excess water intake induces catabolism and water retention. These findings suggest that ß-AR activation induces tissue sodium and potassium retention, leading to body fluid retention, with or without excess water intake. This characterisation of ß-AR-induced electrolyte and fluid abnormalities improves our understanding of the pharmacological effects of ß-AR inhibitors. Significance Statement We have shown that chronic ß-AR stimulation causes cardiac hypertrophy associated with sodium-driven water retention in the heart and increases the accumulation of body sodium, potassium and water at the tissue level. This characterisation of the ß-AR-induced abnormalities in electrolyte and water balance at the tissue level improves our understanding of the roles of ß-AR in physiology and pathophysiology and the pharmacological effects of ß-AR inhibitors.
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In mammals, primordial germ cells (PGCs) enter meiosis and differentiate into primary oocytes in embryonic ovaries. Previously, we demonstrated that meiotic gene induction and meiotic initiation were impaired in female germline cells of conditional knockout (CKO) mice lacking the Smarcb1 (Snf5) gene, which encodes a core subunit of the switching defective/sucrose non-fermenting (SWI/SNF) complex. In this study, we classified meiotic genes expressed at lower levels in Snf5 CKO females into two groups based on promoter accessibility. The promoters of 74% of these genes showed lower accessibility in mutant mice, whereas those of the remaining genes were opened without the SWI/SNF complex. Notably, the former genes included Meiosin, which encodes a transcriptional regulator essential for meiotic gene activation. The promoters of the former and the latter genes were mainly modified with H3K27me3/bivalent and H3K4me3 histone marks, respectively. A subset of the former genes was precociously activated in female PGCs deficient in polycomb repressive complexes (PRCs). Our results point to a mechanism through which the SWI/SNF complex coordinates meiotic gene activation via the remodeling of PRC-repressed genes, including Meiosin, in female germline cells.
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Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona , Animais , Feminino , Camundongos , Cromatina , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Células Germinativas/metabolismo , Mamíferos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação TranscricionalRESUMO
BACKGROUND AND HYPOTHESIS: While the kidney protective effects of sodium glucose co-transporter-2 (SGLT2) inhibitors have attracted much attention, there are limited real-world clinical data examining the effects of SGLT2 inhibitors on kidney function in older individuals. We aimed to compare the kidney outcomes between SGLT2 inhibitor and dipeptidyl peptidase 4 (DPP4) inhibitor use in older adults with diabetes. METHODS: Using a nationwide claims database, we studied 6 354 older adults (≥ 60 years of age) who had diabetes and newly initiated on SGLT2 inhibitors or DPP4 inhibitors. A 1:4 propensity score matching algorithm was used to compare changes in eGFR between SGLT2 inhibitor and DPP4 inhibitor users. The primary outcome was a decline in the rate of estimated glomerular filtration rate (eGFR), which was obtained using a linear mixed-effects model with an unstructured covariance. RESULTS: Following propensity score matching, 6 354 individuals including 1 271 SGLT2 inhibitor users and 5 083 DPP4 inhibitor users (median age: 68 [65-70] years); men, 60.4%; median eGFR:69.0 [59.1-79.0] ml/min/1.73 m2, median hemoglobin A1c [HbA1c]:6.9 [6.5-7.4]%) were analyzed. SGLT2 inhibitor users had a slower eGFR decline than did DPP4 inhibitor users (-0.97 [95% CI, -1.24 to -0.70] ml/min/1.73m2 vs. -1.83 [95% CI, -1.97 to -1.69] ml/min/1.73m2 per year; p for interaction < 0.001). This finding remained consistent across subgroups based on age, sex, body mass index, HbA1c level, renin-angiotensin system inhibitor use, and baseline eGFR. Additionally, the risk of a ≥ 20%, ≥ 30%, and ≥ 40% decrease in eGFR from baseline was significantly lower in SGLT2 inhibitor users than that in DPP4 inhibitor users. CONCLUSIONS: Our analysis, utilizing a nationwide epidemiological dataset, demonstrated that the decline in eGFR was slower in individuals aged ≥ 60 years with diabetes who were prescribed SGLT2 inhibitors compared to those prescribed DPP4 inhibitors, suggesting a potential advantage of SGLT2 inhibitors for kidney outcomes even in older individuals with diabetes.
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AIM: To compare the risk of developing kidney outcomes with use of glucagon-like peptide-1 receptor agonists (GLP-1RAs) versus use of sodium-glucose cotransporter-2 (SGLT2) inhibitors among individuals with diabetes. MATERIALS AND METHODS: In this retrospective observational study, we analysed 12 338 individuals with diabetes who newly initiated SGLT2 inhibitors or GLP-1RAs using data from the JMDC claims database. The primary outcome was change in the estimated glomerular filtration rate (eGFR), estimated using a linear mixed-effects model. A 1:4 propensity-score-matching algorithm was used to compare the changes in eGFR between GLP-1RA and SGLT2 inhibitor users. RESULTS: After propensity-score matching, 2549 individuals (median [range] age 52 [46-58] years, 80.6% men) were analysed (510 GLP-1RA new users and 2039 SGLT2 inhibitor new users). SGLT2 inhibitor use was associated with a slower eGFR decline when compared with GLP-1RA use (-1.41 [95% confidence interval -1.63 to -1.19] mL/min/1.73 m2 vs. -2.62 [95% confidence interval -3.15 to -2.10] mL/min/1.73 m2). CONCLUSIONS: Our analysis demonstrates the potential advantages of SGLT2 inhibitors over GLP-1RAs in terms of kidney outcomes in individuals with diabetes.
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Diabetes Mellitus Tipo 2 , Taxa de Filtração Glomerular , Receptor do Peptídeo Semelhante ao Glucagon 1 , Pontuação de Propensão , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Masculino , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Pessoa de Meia-Idade , Estudos Retrospectivos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/fisiopatologia , Hipoglicemiantes/uso terapêutico , Agonistas do Receptor do Peptídeo 1 Semelhante ao GlucagonRESUMO
AIM: To investigate the clinical significance of body weight changes on kidney outcomes among individuals with diabetes using sodium-glucose cotransporter-2 (SGLT2) inhibitors. MATERIALS AND METHODS: This is a retrospective cohort study using a nationwide epidemiological database, and we conducted an analysis involving 11 569 individuals with diabetes who were newly prescribed SGLT2 inhibitors. The main outcome was the rate of decline in estimated glomerular filtration rate (eGFR), determined through a linear mixed-effects model with an unstructured covariance structure. RESULTS: The median age of the patients was 52 (Q1-Q3: 47-58) years, and the median fasting plasma glucose and glycated haemoglobin (HbA1c) levels were 144 (Q1-Q3: 124-175) mg/dL and 7.4 (Q1-Q3: 6.8-8.3)%, respectively. The median estimated eGFR was 77.7 (Q1-Q3: 67.2-89.1) mL/min/1.73 m2. The median follow-up period was 1.7 (Q1-Q3: 1.0-2.6) years. Participants were stratified into three groups based on the body mass index change rate tertiles between baseline and 1 year after (tertile 1: <-4.55%, tertile 2: -4.55% to -1.43%, tertile 3: >-1.43%). The annual change in eGFR was -0.78 (-0.94 to -0.63) mL/min/1.73 m2 in tertile 1, -0.95 (-1.09 to -0.81) mL/min/1.73 m2 in tertile 2, and -1.65 mL/min/1.73 m2 (-1.84 to -1.47) in tertile 3 (pinteraction < 0.001). A variety of sensitivity analyses confirmed the relationship between the 1-year body mass index decrease and favourable kidney outcomes after SGLT2 inhibitor administration. CONCLUSIONS: Our analysis of a nationwide epidemiological cohort revealed that kidney outcomes following the initiation of SGLT2 inhibitors would be more favourable, with greater body weight loss observed after the initiation of SGLT2 inhibitors.
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BACKGROUND: Hypertension is a major cause of cardiovascular disease (CVD). In patients with hypertension, unawareness of the disease often results in poor blood pressure control and increases the risk of CVD. However, data in nationwide surveys regarding the proportion of unaware individuals and the implications of such on their clinical outcomes are lacking. We aimed to clarify the association between unawareness of being prescribed antihypertensive medications among individuals taking antihypertensive medications and the subsequent risk of developing CVD.MethodsâandâResults: This retrospective cohort study analyzed data from the JMDC Claims Database, including 313,715 individuals with hypertension treated with antihypertensive medications (median age 56 years). The primary endpoint was a composite of myocardial infarction, angina pectoris, stroke, heart failure, and atrial fibrillation. Overall, 19,607 (6.2%) individuals were unaware of being prescribed antihypertensive medications. During the follow-up period, 33,976 composite CVD endpoints were documented. Despite their youth, minimal comorbidities, and the achievement of better BP control with a reduced number of antihypertensive prescriptions, unawareness of being prescribed antihypertensive medications was associated with a greater risk of developing composite CVD. Hazard ratios of unawareness of being prescribed antihypertensive medications were 1.16 for myocardial infarction, 1.25 for angina pectoris, 1.15 for stroke, 1.36 for heart failure, and 1.28 for atrial fibrillation. The results were similar in several sensitivity analyses, including the analysis after excluding individuals with dementia. CONCLUSIONS: Among individuals taking antihypertensive medications, assessing the awareness of being prescribed antihypertensive medications may help identify those at high risk for CVD-related events.
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2-Deoxy-d-glucose (2DG) induces anticancer effects through glycolytic inhibition but it may raise the risk of arrhythmia. The rare monosaccharide d-allose also has anticancer properties, but its cardiac effects are unknown. We examined the effects of d-allose on adenosine triphosphate (ATP) production in neonatal rat cardiomyocytes. We showed that 25 mM d-allose selectively reduced glycolytic ATP, but had minimal impact on mitochondrial ATP, while 1 mM 2DG strongly inhibited both. Furthermore, d-allose had less impact on cell viability and was less cytotoxic than 2DG; neither compound caused apoptosis. Thus, d-allose selectively diminished glycolytic ATP production with no apparent effects on cardiomyocytes.
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Trifosfato de Adenosina , Miócitos Cardíacos , Ratos , Animais , Animais Recém-Nascidos , Sobrevivência Celular , Glucose/farmacologiaRESUMO
BACKGROUND: Although vaccination has been reported to reduce the morbidity and severity of COVID-19 infection in patients with kidney disease, gross hematuria is frequently reported following vaccination in patients with IgA nephropathy. We investigated the frequency of gross hematuria following COVID-19 vaccination and its effect on renal function in IgA nephropathy patients. METHODS: Adverse reactions after two or more COVID-19 vaccine doses were investigated in 295 IgA nephropathy patients attending Osaka Cty general hospital from September 2021 to November 2022. We compared differences in background characteristics and other adverse reactions between groups with and without gross hematuria after vaccination, and examined changes in renal function and proteinuria. RESULTS: Twenty-eight patients (9.5%) had gross hematuria. The median age of patients with and without gross hematuria was 44 (29-48) and 49 (42-61) years, respectively, indicating a significant difference. The percentage of patients with microscopic hematuria before vaccination differed significantly between those with (65.2%) and without (32%) gross hematuria. Adverse reactions, such as fever, chills, headache and arthralgia, were more frequent in patients with gross hematuria. There was no difference in renal functional decline after approximately 1 year between patients with and without gross hematuria. We also found no significant changes in estimated glomerular filtration rate or proteinuria before and after vaccination in the gross hematuria group. However, some patients clearly had worsening of renal function. CONCLUSIONS: While COVID-19 vaccination is beneficial, care is required since it might adversely affect renal function in some patients.
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BACKGROUND: Pulmonary arterial hypertension is a serious medical condition. However, the condition is often misdiagnosed or a rather long delay occurs from symptom onset to diagnosis, associated with decreased 5-year survival. In this study, we developed and tested a deep-learning algorithm to detect pulmonary arterial hypertension using chest X-ray (CXR) images. METHODS: From the image archive of Chiba University Hospital, 259 CXR images from 145 patients with pulmonary arterial hypertension and 260 CXR images from 260 control patients were identified; of which 418 were used for training and 101 were used for testing. Using the testing dataset for each image, the algorithm outputted a numerical value from 0 to 1 (the probability of the pulmonary arterial hypertension score). The training process employed a binary cross-entropy loss function with stochastic gradient descent optimization (learning rate parameter, α = 0.01). In addition, using the same testing dataset, the algorithm's ability to identify pulmonary arterial hypertension was compared with that of experienced doctors. RESULTS: The area under the curve (AUC) of the receiver operating characteristic curve for the detection ability of the algorithm was 0.988. Using an AUC threshold of 0.69, the sensitivity and specificity of the algorithm were 0.933 and 0.982, respectively. The AUC of the algorithm's detection ability was superior to that of the doctors. CONCLUSION: The CXR image-derived deep-learning algorithm had superior pulmonary arterial hypertension detection capability compared with that of experienced doctors.
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Aprendizado Profundo , Hipertensão Arterial Pulmonar , Humanos , Inteligência Artificial , Hipertensão Arterial Pulmonar/diagnóstico por imagem , Raios X , TóraxRESUMO
BRD4 is a BET family protein that binds acetylated histones and regulates transcription. BET/BRD4 inhibitors block blood cancer growth and inflammation and serve as a new therapeutic strategy. However, the biological role of BRD4 in normal hematopoiesis and inflammation is not fully understood. Analysis of Brd4 conditional knockout (KO) mice showed that BRD4 is required for hematopoietic stem cell expansion and progenitor development. Nevertheless, BRD4 played limited roles in macrophage development and inflammatory response to LPS ChIP-seq analysis showed that despite its limited importance, BRD4 broadly occupied the macrophage genome and participated in super-enhancer (SE) formation. Although BRD4 is critical for SE formation in cancer, BRD4 was not required for macrophage SEs, as KO macrophages created alternate, BRD4-less SEs that compensated BRD4 loss. This and additional mechanisms led to the retention of inflammatory responses in macrophages. Our results illustrate a context-dependent role of BRD4 and plasticity of epigenetic regulation.
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Biomarcadores/análise , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Inflamação/imunologia , Macrófagos Peritoneais/imunologia , Proteínas Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Animais , Células Cultivadas , Perfilação da Expressão Gênica , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
Homeostasis of body fluid is a key component for maintaining health. An imbalance of body sodium and water causes various pathological states, such as dehydration, volume overload, hypertension, cardiovascular and renal diseases, and metabolic disorders. Conventional concepts regarding physiology and pathophysiology of body sodium and water balance have been established by several assumptions. These assumptions are that the kidneys are the master regulator of body sodium and water content, and that sodium moves inside the body in parallel with water. However, recent clinical and basic studies have proposed alternative concepts. These concepts are that body sodium and water balance are regulated by various organs and multiple factors, such as physical activity and the environment, and that sodium accumulates locally in tissues independently of the blood status and/or water. Various concerns remain unclear, and the regulatory mechanism of body sodium, fluid, and blood pressure needs to be readdressed. In the present review article, we discuss novel concepts regarding the regulation of body sodium, water, and blood pressure with a particular focus on the systemic water conservation system and fluid loss-triggered elevation in blood pressure.
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Líquidos Corporais , Hipertensão , Humanos , Pressão Sanguínea/fisiologia , Sódio/metabolismo , Líquidos Corporais/metabolismo , ÁguaRESUMO
BACKGROUND: We previously found that (pro)renin receptor ((P)RR) augments Wnt3 protein without affecting Wnt3 gene transcription in colorectal cancer (CRC) cells, thus contributes to CRC initiation. The present study aims to investigate whether (P)RR further promotes CRC progression following oncogenesis and the related mechanisms. Notably, we deeply elaborate how (P)RR affects Wnt3 protein level and the key enzyme that mediates this process. METHODS: Immunohistochemistry, western blotting and immunofluorescence were performed to detect protein expression status. A kind of gastrointestinal epithelium-specific ATP6AP2 ((P)RR encoding gene) knock-in mice were generated using Crispr/Cas9 system. RESULTS: We found that increased (P)RR expression in primary CRC lesions is positively associated with higher Wnt3 protein level and disease progression. Progressive CRC presents less colocalization of Wnt3 and an E3 ubiquitin ligase NEDD4L in primary lesions than non-progressive CRC. In colon cancer cells, (P)RR dramatically inhibits the NEDD4L-mediated Wnt3 protein ubiquitination. ATP6AP2 knock-in mice show more diminished Wnt3-NEDD4L colocalization in their gut epithelium in comparison to wildtype mice. They also have abnormal gut bacterial flora distribution. Especially, Lachnospiraceae_NK4A136 and Bacteroides genus, which are generally protective against CRC, are suppressed in guts of ATP6AP2 knock-in mice. CONCLUSIONS: Collectively, (P)RR promotes CRC progression through inhibiting the NEDD4L-mediated Wnt3 ubiquitination and modulating gut microbiota. Video Abstract.
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Neoplasias Colorretais , Microbioma Gastrointestinal , Animais , Camundongos , Receptor de Pró-Renina , Proteína Wnt3/genética , Proteína Wnt3/metabolismo , Ubiquitinação , Receptores de Superfície Celular/metabolismo , Neoplasias Colorretais/patologiaRESUMO
INTRODUCTION: While recent investigations show that klotho exerts renoprotective actions, it has not been fully addressed whether klotho protein supplementation reverses renal damage. METHODS: The impacts of subcutaneous klotho supplementation on rats with subtotal nephrectomy were examined. Animals were divided into 3 groups: group 1 (short remnant [SR]): remnant kidney for 4 weeks, group 2 (long remnant [LR]): remnant kidney for 12 weeks, and group 3 (klotho supplementation [KL]): klotho protein (20 µg/kg/day) supplementation on the remnant kidney. Blood pressure, blood and urine compositions with conventional methods such as enzyme-linked immunosorbent assay and radioimmunoassay, kidney histology, and renal expressions of various genes were analyzed. In vitro studies were also performed to support in vivo findings. RESULTS: Klotho protein supplementation decreased albuminuria (-43%), systolic blood pressure (-16%), fibroblast growth factor (FGF) 23 (-51%) and serum phosphate levels (-19%), renal angiotensin II concentration (-43%), fibrosis index (-70%), renal expressions of collagen I (-55%), and transforming growth factor ß (-59%) (p < 0.05 for all). Klotho supplementation enhanced fractional excretion of phosphate (+45%), glomerular filtration rate (+76%), renal expressions of klotho (+148%), superoxide dismutase (+124%), and bone morphogenetic protein (BMP) 7 (+174%) (p < 0.05 for all). CONCLUSION: Our data indicated that klotho protein supplementation inactivated renal renin-angiotensin system, reducing blood pressure and albuminuria in remnant kidney. Furthermore, exogenous klotho protein supplementation elevated endogenous klotho expression to increase phosphate excretion with resultant reductions in FGF23 and serum phosphate. Finally, klotho supplementation reversed renal dysfunction and fibrosis in association with improved BMP7 in remnant kidney.
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Albuminúria , Nefropatias , Animais , Ratos , Albuminúria/metabolismo , Suplementos Nutricionais , Fibrose , Rim/patologia , Nefropatias/patologia , Proteínas Klotho/uso terapêutico , Fosfatos/metabolismoRESUMO
BACKGROUND: Macroglossia is one of the clinical signs that emerges in patients with amyotrophic lateral sclerosis (ALS) who are undergoing invasive ventilation. OBJECTIVE: We aimed to investigate the relationship between the progression of macroglossia and the clinical characteristics during the advanced stages of ALS. METHODS: Forty-one patients with ALS using invasive ventilation with tracheostomy were prospectively followed over a 3-year period. We evaluated the prevalence of macroglossia, motor disabilities including oral function, communication ability (communication stage I to V) as a marker of disease progression, and nutritional factors. We analyzed the potential factors affecting the progression of macroglossia using a multivariate logistic analysis. RESULTS: The number of patients with macroglossia was increased during the follow-up (from 24.4 to 53.7%), while the communication stage progressed from 2.6 in average (SD 1.7) to 3.5 (1.4). During the study, body weight increased, while energy intake decreased, suggesting progressive hypometabolism. Eight patients had newly developed macroglossia during the study and showed greater progression of communication impairment than those without macroglossia. Multivariate logistic regression analysis showed that communication impairment was a factor associated with macroglossia. CONCLUSION: Macroglossia in advanced ALS with invasive ventilation is associated with disease progression.
Assuntos
Esclerose Lateral Amiotrófica , Macroglossia , Humanos , Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/terapia , Macroglossia/epidemiologia , Macroglossia/complicações , Relevância Clínica , Progressão da DoençaRESUMO
Metabolic syndrome (MetS) is a rapidly increasing health concern during midlife and is an emerging risk factor for the development of neurodegenerative diseases, such as Alzheimer's disease (AD). While angiotensin receptor blockers (ARB) are widely used for MetS-associated hypertension and kidney disease, its therapeutic potential in the brain during MetS are not well-described. Here, we tested whether treatment with ARB could alleviate the brain pathology and inflammation associated with MetS using the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. Here, we report that chronic ARB treatment with olmesartan (10 mg/kg/day by oral gavage for 6 weeks) partially but significantly ameliorated accumulation of oxidized and ubiquitinated proteins, astrogliosis and transformation to neurotoxic astrocytes in the brain of old OLETF rats, which otherwise exhibit the progression of these pathological hallmarks associated with MetS. Additionally, olmesartan treatment restored claudin-5 and ZO-1, markers of the structural integrity of the blood-brain barrier as well as synaptic protein PSD-95, which were otherwise decreased in old OLETF rats, particularly in the hippocampus, a critical region in cognition, memory and AD. These data demonstrate that the progression of MetS in OLETF rats is associated with deterioration of various aspects of neuronal integrity that may manifest neurodegenerative conditions and that overactivation of angiotensin receptor directly or indirectly contributes to these detriments. Thus, olmesartan treatment may slow or delay the onset of degenerative process in the brain and subsequent neurological disorders associated with MetS.