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1.
Int J Mol Sci ; 25(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474208

RESUMO

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a prevalent clinical condition associated with elevated morbidity and mortality rates. Patients with MASLD treated with semaglutide, a glucagon-like peptide-1 receptor agonist, demonstrate improvement in terms of liver damage. However, the mechanisms underlaying this beneficial effect are not yet fully elucidated. We investigated the efficacy of semaglutide in halting MASLD progression using a genetic mouse model of diabesity. Leptin-receptor-deficient mice with obesity and diabetes (BKS db/db) were either untreated or administered with semaglutide for 11 weeks. Changes in food and water intake, body weight and glycemia were monitored throughout the study. Body fat composition was assessed by dual-energy X-ray absorptiometry. Upon sacrifice, serum biochemical parameters, liver morphology, lipidomic profile and liver-lipid-related pathways were evaluated. The semaglutide-treated mice exhibited lower levels of glycemia, body weight, serum markers of liver dysfunction and total and percentage of fat mass compared to untreated db/db mice without a significant reduction in food intake. Histologically, semaglutide reduced hepatic steatosis, hepatocellular ballooning and intrahepatic triglycerides. Furthermore, the treatment ameliorated the hepatic expression of de novo lipogenesis markers and modified lipid composition by increasing the amount of polyunsaturated fatty acids. The administration of semaglutide to leptin-receptor-deficient, hyperphagic and diabetic mice resulted in the amelioration of MASLD, likely independently of daily caloric intake, suggesting a direct effect of semaglutide on the liver through modulation of the lipid profile.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Fígado Gorduroso , Peptídeos Semelhantes ao Glucagon , Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Lipogênese , Leptina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Fígado Gorduroso/metabolismo , Obesidade/metabolismo , Fígado/metabolismo , Peso Corporal , Triglicerídeos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Camundongos Obesos
2.
Cell Mol Life Sci ; 81(1): 84, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345631

RESUMO

C3G is a Rap1 GEF that plays a pivotal role in platelet-mediated processes such as angiogenesis, tumor growth, and metastasis by modulating the platelet secretome. Here, we explore the mechanisms through which C3G governs platelet secretion. For this, we utilized animal models featuring either overexpression or deletion of C3G in platelets, as well as PC12 cell clones expressing C3G mutants. We found that C3G specifically regulates α-granule secretion via PKCδ, but it does not affect δ-granules or lysosomes. C3G activated RalA through a GEF-dependent mechanism, facilitating vesicle docking, while interfering with the formation of the trans-SNARE complex, thereby restricting vesicle fusion. Furthermore, C3G promotes the formation of lamellipodia during platelet spreading on specific substrates by enhancing actin polymerization via Src and Rac1-Arp2/3 pathways, but not Rap1. Consequently, C3G deletion in platelets favored kiss-and-run exocytosis. C3G also controlled granule secretion in PC12 cells, including pore formation. Additionally, C3G-deficient platelets exhibited reduced phosphatidylserine exposure, resulting in decreased thrombin generation, which along with defective actin polymerization and spreading, led to impaired clot retraction. In summary, platelet C3G plays a dual role by facilitating platelet spreading and clot retraction through the promotion of outside-in signaling while concurrently downregulating α-granule secretion by restricting granule fusion.


Assuntos
Actinas , Plaquetas , Retração do Coágulo , Fator 2 de Liberação do Nucleotídeo Guanina , Animais , Actinas/metabolismo , Plaquetas/metabolismo , Exocitose/fisiologia , Hemostasia , Fator 2 de Liberação do Nucleotídeo Guanina/metabolismo
3.
Mol Ther Nucleic Acids ; 34: 102041, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37842165

RESUMO

Diabetic kidney disease (DKD) is a common microvascular complication of diabetes, a global health issue. Hyperglycemia, in concert with cytokines, activates the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway to induce inflammation and oxidative stress contributing to renal damage. There is evidence of microRNA-155 (miR-155) involvement in diabetes complications, but the underlying mechanisms are unclear. In this study, gain- and loss-of-function experiments were conducted to investigate the interplay between miR-155-5p and suppressor of cytokine signaling 1 (SOCS1) in the regulation of the JAK/STAT pathway during renal inflammation and DKD. In experimental models of mesangial injury and diabetes, miR-155-5p expression correlated inversely with SOCS1 and positively with albuminuria and expression levels of cytokines and prooxidant genes. In renal cells, miR-155-5p mimic downregulated SOCS1 and promoted STAT1/3 activation, cytokine expression, and cell proliferation and migration. Conversely, both miR-155-5p antagonism and SOCS1 overexpression protected cells from inflammation and hyperglycemia damage. In vivo, SOCS1 gene delivery decreased miR-155-5p and kidney injury in diabetic mice. Moreover, therapeutic inhibition of miR-155-5p suppressed STAT1/3 activation and alleviated albuminuria, mesangial damage, and renal expression of inflammatory and fibrotic genes. In conclusion, modulation of the miR-155/SOCS1 axis protects kidneys against diabetic damage, thus highlighting its potential as therapeutic target for DKD.

4.
AoB Plants ; 15(4): plad057, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37649982

RESUMO

Anagenetic speciation is an important mode of evolution in oceanic islands, yet relatively understudied compared to adaptive radiation. In the Macaronesian region, three closely related species of Artemisia (i.e. A. argentea, A. thuscula and A. gorgonum) are each endemic from a single archipelago (i.e. Madeira, Canary Islands and Cape Verde, respectively), representing a perfect opportunity to study three similar but independent anagenetic speciation processes. By analysing plastid and nuclear DNA sequences, as well as nuclear DNA amount data, generated from a comprehensive sampling in all the islands and archipelagos where these species are currently distributed, we intend to find common evolutionary patterns that help us explain the limited taxonomic diversification experienced by endemic Macaronesian Artemisia. Our time-calibrated phylogenetic reconstruction suggested that divergence among the three lineages occurred in a coincidental short period of time during the Pleistocene. Haplotype and genetic differentiation analyses showed similar diversity values among A. argentea, A. thuscula and A. gorgonum. Clear phylogeographic patterns-showing comparable genetic structuring among groups of islands-were also found within the three archipelagos. Even from the cytogenetic point of view, the three species presented similarly lower genome size values compared to the mainland closely related species A. arborescens. We hypothesize that the limited speciation experienced by the endemic Artemisia in Madeira, Canary Islands and Cape Verde archipelagos could be related to their recent parallel evolutionary histories as independent lineages, combined with certain shared characteristics of seed dispersal, pollen transport and type of habitat.

5.
Clín. investig. arterioscler. (Ed. impr.) ; 35(4): 185-194, Juli-Agos. 2023. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-223628

RESUMO

Introducción: El aneurisma aórtico abdominal (AAA) es una afección degenerativa y multifactorial caracterizada por una dilatación progresiva de la aorta y activación crónica de inflamación, actividad proteolítica y estrés oxidativo en la pared vascular. La respuesta inmune dependiente de anticuerpos IgG frente a antígenos expuestos en el vaso dañado está implicada en la formación y progresión del AAA, aunque los mecanismos no son del todo conocidos. En este trabajo analizamos la funcionalidad de los receptores Fc de IgG (FcγR), en particular los expresados por el monocito/macrófago, en el desarrollo del AAA experimental. Métodos: En el modelo de AAA inducido por perfusión aórtica de elastasa se examinaron, mediante histología y PCR cuantitativa, las aortas abdominales de ratones de fenotipo salvaje y de ratones deficientes en FcγR, sin y con transferencia adoptiva de macrófagos. In vitro, macrófagos murinos se transfectaron con ARN de interferencia de FcγRIV/CD16.2 o se trataron con un inhibidor de la cinasa Syk antes de la estimulación con inmunocomplejos de IgG. Resultados: La transferencia adoptiva de macrófagos a ratones deficientes en FcγR incrementó su susceptibilidad al desarrollo de AAA. En los ratones que recibieron macrófagos con FcγR funcionales se observó un mayor incremento del diámetro aórtico y del contenido de macrófagos y linfocitos B, así como un aumento en la expresión de la quimiocina CCL2, las citocinas TNF-α e IL-17, la metaloproteinasa MMP2, la enzima prooxidante NADPH oxidasa-2 y las isoformas FcγRIII/CD16 y FcγRIV/CD16.2. In vitro, tanto el silenciamiento génico de FcγRIV/CD16.2 como la inhibición de Syk en macrófagos redujeron la producción de citocinas y anión superóxido inducida por inmunocomplejos...(AU)


Introduction: Abdominal aortic aneurysm (AAA) is a multifactorial, degenerative disease characterized by progressive aortic dilation and chronic activation of inflammation, proteolytic activity, and oxidative stress in the aortic wall. The immune response triggered by antibodies against antigens present in the vascular wall participates in the formation and progression of AAA through mechanisms not completely understood. This work analyses the function of specific IgG receptors (FcγR), especially those expressed by monocytes/macrophages, in the development of experimental AAA. Methods: In the elastase-induced AAA model, the abdominal aortas from wildtype and FcγR deficient mice with/without macrophage adoptive transfer were analysed by histology and quantitative PCR. In vitro, mouse macrophages were transfected with RNA interference of FcγRIV/CD16.2 or treated with Syk kinase inhibitor before stimulation with IgG immune complexes. Results: Macrophage adoptive transfer in FcγR deficient mice increased the susceptibility to AAA development. Mice receiving macrophages with functional FcγR exhibited higher aortic diameter increase, higher content of macrophages and B lymphocytes, and upregulated expression of chemokine CCL2, cytokines (TNF-α and IL-17), metalloproteinase MMP2, prooxidant enzyme NADPH oxidase-2, and the isoforms FcγRIII/CD16 and FcγRIV/CD16.2. In vitro, both FcγRIV/CD16.2 gene silencing and Syk inhibition reduced cytokines and reactive oxygen species production induced by immune complexes in macrophages. Conclusions: Activation of macrophage FcγR contributes to AAA development by inducing mediators of inflammation, proteolysis, and oxidative stress. Modulation of FcγR or effector molecules may represent a potential target for AAA treatment.


Assuntos
Humanos , Receptores Fc , Ativação de Macrófagos , Aneurisma da Aorta Abdominal , Estresse Oxidativo
6.
Clin Investig Arterioscler ; 35(4): 185-194, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36737385

RESUMO

INTRODUCTION: Abdominal aortic aneurysm (AAA) is a multifactorial, degenerative disease characterized by progressive aortic dilation and chronic activation of inflammation, proteolytic activity, and oxidative stress in the aortic wall. The immune response triggered by antibodies against antigens present in the vascular wall participates in the formation and progression of AAA through mechanisms not completely understood. This work analyses the function of specific IgG receptors (FcγR), especially those expressed by monocytes/macrophages, in the development of experimental AAA. METHODS: In the elastase-induced AAA model, the abdominal aortas from wildtype and FcγR deficient mice with/without macrophage adoptive transfer were analysed by histology and quantitative PCR. In vitro, mouse macrophages were transfected with RNA interference of FcγRIV/CD16.2 or treated with Syk kinase inhibitor before stimulation with IgG immune complexes. RESULTS: Macrophage adoptive transfer in FcγR deficient mice increased the susceptibility to AAA development. Mice receiving macrophages with functional FcγR exhibited higher aortic diameter increase, higher content of macrophages and B lymphocytes, and upregulated expression of chemokine CCL2, cytokines (TNF-α and IL-17), metalloproteinase MMP2, prooxidant enzyme NADPH oxidase-2, and the isoforms FcγRIII/CD16 and FcγRIV/CD16.2. In vitro, both FcγRIV/CD16.2 gene silencing and Syk inhibition reduced cytokines and reactive oxygen species production induced by immune complexes in macrophages. CONCLUSIONS: Activation of macrophage FcγR contributes to AAA development by inducing mediators of inflammation, proteolysis, and oxidative stress. Modulation of FcγR or effector molecules may represent a potential target for AAA treatment.


Assuntos
Aneurisma da Aorta Abdominal , Receptores de IgG , Animais , Camundongos , Receptores de IgG/genética , Receptores de IgG/metabolismo , Receptores Fc/metabolismo , Complexo Antígeno-Anticorpo/efeitos adversos , Complexo Antígeno-Anticorpo/metabolismo , Camundongos Knockout , Aneurisma da Aorta Abdominal/induzido quimicamente , Macrófagos/metabolismo , Citocinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Imunoglobulina G/efeitos adversos , Imunoglobulina G/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
7.
Cell Commun Signal ; 21(1): 30, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737758

RESUMO

BACKGROUND: C3G is a guanine nucleotide exchange factor (GEF) that activates Rap1 to promote cell adhesion. Resting C3G is autoinhibited and the GEF activity is released by stimuli that signal through tyrosine kinases. C3G is activated by tyrosine phosphorylation and interaction with Crk adaptor proteins, whose expression is elevated in multiple human cancers. However, the molecular details of C3G activation and the interplay between phosphorylation and Crk interaction are poorly understood. METHODS: We combined biochemical, biophysical, and cell biology approaches to elucidate the mechanisms of C3G activation. Binding of Crk adaptor proteins to four proline-rich motifs (P1 to P4) in C3G was characterized in vitro using isothermal titration calorimetry and sedimentation velocity, and in Jurkat and HEK293T cells by affinity pull-down assays. The nucleotide exchange activity of C3G over Rap1 was measured using nucleotide-dissociation kinetic assays. Jurkat cells were also used to analyze C3G translocation to the plasma membrane and the C3G-dependent activation of Rap1 upon ligation of T cell receptors. RESULTS: CrkL interacts through its SH3N domain with sites P1 and P2 of inactive C3G in vitro and in Jurkat and HEK293T cells, and these sites are necessary to recruit C3G to the plasma membrane. However, direct stimulation of the GEF activity requires binding of Crk proteins to the P3 and P4 sites. P3 is occluded in resting C3G and is essential for activation, while P4 contributes secondarily towards complete stimulation. Tyrosine phosphorylation of C3G alone causes marginal activation. Instead, phosphorylation primes C3G lowering the concentration of Crk proteins required for activation and increasing the maximum activity. Unexpectedly, optimal activation also requires the interaction of CrkL-SH2 domain with phosphorylated C3G. CONCLUSION: Our study revealed that phosphorylation of C3G by Src and Crk-binding form a two-factor mechanism that ensures tight control of C3G activation. Additionally, the simultaneous SH2 and SH3N interaction of CrkL with C3G, required for the activation, reveals a novel adaptor-independent function of Crk proteins relevant to understanding their role in physiological signaling and their deregulation in diseases. Video abstract.


Assuntos
Fator 2 de Liberação do Nucleotídeo Guanina , Proteínas Nucleares , Humanos , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fator 2 de Liberação do Nucleotídeo Guanina/metabolismo , Células HEK293 , Proteínas Nucleares/metabolismo , Nucleotídeos/metabolismo , Proteínas Proto-Oncogênicas c-crk/metabolismo , Domínios de Homologia de src , Tirosina/metabolismo
8.
Front Nutr ; 10: 1079407, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845063

RESUMO

Introduction: The lower rates of cardiovascular disease in Southern Europe could be partially explained by the low prevalence of lipid-rich atheroma plaques. Consumption of certain foods affects the progression and severity of atherosclerosis. We investigated whether the isocaloric inclusion of walnuts within an atherogenic diet prevents phenotypes predicting unstable atheroma plaque in a mouse model of accelerated atherosclerosis. Methods: Apolipoprotein E-deficient male mice (10-week-old) were randomized to receive a control diet (9.6% of energy as fat, n = 14), a palm oil-based high-fat diet (43% of energy as fat, n = 15), or an isocaloric diet in which part of palm oil was replaced by walnuts in a dose equivalent to 30 g/day in humans (n = 14). All diets contained 0.2% cholesterol. Results: After 15 weeks of intervention, there were no differences in size and extension in aortic atherosclerosis among groups. Compared to control diet, palm oil-diet induced features predicting unstable atheroma plaque (higher lipid content, necrosis, and calcification), and more advanced lesions (Stary score). Walnut inclusion attenuated these features. Palm oil-based diet also boosted inflammatory aortic storm (increased expression of chemokines, cytokines, inflammasome components, and M1 macrophage phenotype markers) and promoted defective efferocytosis. Such response was not observed in the walnut group. The walnut group's differential activation of nuclear factor kappa B (NF-κB; downregulated) and Nrf2 (upregulated) in the atherosclerotic lesion could explain these findings. Conclusion: The isocaloric inclusion of walnuts in an unhealthy high-fat diet promotes traits predicting stable advanced atheroma plaque in mid-life mice. This contributes novel evidence for the benefits of walnuts, even in an unhealthy dietary environment.

9.
Antioxidants (Basel) ; 11(12)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36552707

RESUMO

In diabetes, chronic hyperglycemia, dyslipidemia, inflammation and oxidative stress contribute to the progression of macro/microvascular complications. Recently, benefits of the use of flavonoids in these conditions have been established. This study investigates, in two different mouse models of diabetes, the vasculoprotective effects of the synthetic flavonoid hidrosmin on endothelial dysfunction and atherogenesis. In a type 2 diabetes model of leptin-receptor-deficient (db/db) mice, orally administered hidrosmin (600 mg/kg/day) for 16 weeks markedly improved vascular function in aorta and mesenteric arteries without affecting vascular structural properties, as assessed by wire and pressure myography. In streptozotocin-induced type 1 diabetic apolipoprotein E-deficient mice, hidrosmin treatment for 7 weeks reduced atherosclerotic plaque size and lipid content; increased markers of plaque stability; and decreased markers of inflammation, senescence and oxidative stress in aorta. Hidrosmin showed cardiovascular safety, as neither functional nor structural abnormalities were noted in diabetic hearts. Ex vivo, hidrosmin induced vascular relaxation that was blocked by nitric oxide synthase (NOS) inhibition. In vitro, hidrosmin stimulated endothelial NOS activity and NO production and downregulated hyperglycemia-induced inflammatory and oxidant genes in vascular smooth muscle cells. Our results highlight hidrosmin as a potential add-on therapy in the treatment of macrovascular complications of diabetes.

10.
Int J Mol Sci ; 23(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36361662

RESUMO

The dentate gyrus (DG) of the human hippocampus is a complex and dynamic structure harboring mature and immature granular neurons in diverse proliferative states. While most mammals show persistent neurogenesis through adulthood, human neurogenesis is still under debate. We found nuclear alterations in granular cells in autopsied human brains, detected by immunohistochemistry. These alterations differ from those reported in pyramidal neurons of the hippocampal circuit. Aging and early AD chromatin were clearly differentiated by the increased epigenetic markers H3K9me3 (heterochromatin suppressive mark) and H3K4me3 (transcriptional euchromatin mark). At early AD stages, lamin B2 was redistributed to the nucleoplasm, indicating cell-cycle reactivation, probably induced by hippocampal nuclear pathology. At intermediate and late AD stages, higher lamin B2 immunopositivity in the perinucleus suggests fewer immature neurons, less neurogenesis, and fewer adaptation resources to environmental factors. In addition, senile samples showed increased nuclear Tau interacting with aged chromatin, likely favoring DNA repair and maintaining genomic stability. However, at late AD stages, the progressive disappearance of phosphorylated Tau forms in the nucleus, increased chromatin disorganization, and increased nuclear autophagy support a model of biphasic neurogenesis in AD. Therefore, designing therapies to alleviate the neuronal nuclear pathology might be the only pathway to a true rejuvenation of brain circuits.


Assuntos
Doença de Alzheimer , Animais , Humanos , Adulto , Idoso , Doença de Alzheimer/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , Hipocampo/metabolismo , Encéfalo/metabolismo , Cromatina/metabolismo , Mamíferos/genética
11.
Front Cell Dev Biol ; 10: 1026287, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36393850

RESUMO

C3G is a Rap1 guanine nucleotide exchange factor that controls platelet activation, aggregation, and the release of α-granule content. Transgenic expression of C3G in platelets produces a net proangiogenic secretome through the retention of thrombospondin-1. In a physiological context, C3G also promotes megakaryocyte maturation and proplatelet formation, but without affecting mature platelet production. The aim of this work is to investigate whether C3G is involved in pathological megakaryopoiesis, as well as its specific role in platelet mediated angiogenesis and tumor metastasis. Using megakaryocyte-specific C3G knockout and transgenic mouse models, we found that both C3G overexpression and deletion promoted platelet-mediated angiogenesis, induced by tumor cell implantation or hindlimb ischemia, through differential release of proangiogenic and antiangiogenic factors. However, only C3G deletion resulted in a higher recruitment of hemangiocytes from the bone marrow. In addition, C3G null expression enhanced thrombopoietin (TPO)-induced platelet production, associated with reduced TPO plasma levels. Moreover, after 5-fluorouracil-induced platelet depletion and rebound, C3G knockout mice showed a defective return to homeostatic platelet levels, indicating impaired platelet turnover. Mechanistically, C3G promotes c-Mpl ubiquitination by inducing Src-mediated c-Cbl phosphorylation and participates in c-Mpl degradation via the proteasome and lysosome systems, affecting TPO internalization. We also unveiled a positive role of platelet C3G in tumor cell-induced platelet aggregation, which facilitated metastatic cell homing and adhesion. Overall, these findings revealed that C3G plays a crucial role in platelet-mediated angiogenesis and metastasis, as well as in platelet level modulation in response to pathogenic stimuli.

12.
Front Pharmacol ; 13: 866574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225571

RESUMO

Wernicke's encephalopathy (WE) is a neurologic disease caused by vitamin B1 or thiamine deficiency (TD), being the alcohol use disorder its main risk factor. WE patients present limiting motor, cognitive, and emotional alterations related to a selective cerebral vulnerability. Neuroinflammation has been proposed to be one of the phenomena that contribute to brain damage. Our previous studies provide evidence for the involvement of the innate immune receptor Toll-like (TLR)4 in the inflammatory response induced in the frontal cortex and cerebellum in TD animal models (animals fed with TD diet [TDD] and receiving pyrithiamine). Nevertheless, the effects of the combination of chronic alcohol consumption and TD on TLR4 and their specific contribution to the pathogenesis of WE are currently unknown. In addition, no studies on TLR4 have been conducted on WE patients since brains from these patients are difficult to achieve. Here, we used rat models of chronic alcohol (CA; 9 months of forced consumption of 20% (w/v) alcohol), TD hit (TDD + daily 0.25 mg/kg i.p. pyrithiamine during 12 days), or combined treatment (CA + TDD) to check the activation of the proinflammatory TLR4/MyD88 pathway and related markers in the frontal cortex and the cerebellum. In addition, we characterized for the first time the TLR4 and its coreceptor MyD88 signature, along with other markers of this proinflammatory signaling such as phospo-NFκB p65 and IκBα, in the postmortem human frontal cortex and cerebellum (gray and white matter) of an alcohol-induced WE patient, comparing it with negative (no disease) and positive (aged brain with Alzheimer's disease) control subjects for neuroinflammation. We found an increase in the cortical TLR4 and its adaptor molecule MyD88, together with an upregulation of the proinflammatory signaling molecules p-NF-ĸB and IĸBα in the CA + TDD animal model. In the patient diagnosed with alcohol-induced WE, we observed cortical and cerebellar upregulation of the TLR4/MyD88 pathway. Hence, our findings provide evidence, both in the animal model and the human postmortem brain, of the upregulation of the TLR4/MyD88 proinflammatory pathway in alcohol consumption-related WE.

13.
Int J Biol Sci ; 18(15): 5873-5884, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263169

RESUMO

Previous data indicate that C3G (RapGEF1) main isoform is highly expressed in liver progenitor cells (or oval cells) compared to adult mature hepatocytes, suggesting it may play an important role in oval cell biology. Hence, we have explored C3G function in the regulation of oval cell properties by permanent gene silencing using shRNAs. We found that C3G knock-down enhanced migratory and invasive ability of oval cells by promoting a partial epithelial to mesenchymal transition (EMT). This is likely mediated by upregulation of mRNA expression of the EMT-inducing transcription factors, Snail1, Zeb1 and Zeb2, induced in C3G-silenced oval cells. This EMT is associated to a higher expression of the stemness markers, CD133 and CD44. Moreover, C3G down-regulation increased oval cells clonogenic capacity by enhancing cell scattering. However, C3G knock-down did not impair oval cell differentiation into hepatocyte lineage. Mechanistic studies revealed that HGF/MET signaling and its pro-invasive activity was impaired in oval cells with low levels of C3G, while TGF-ß signaling was increased. Altogether, these data suggest that C3G might be tightly regulated to ensure liver repair in chronic liver diseases such as non-alcoholic steatohepatitis. Hence, reduced C3G levels could facilitate oval cell expansion, after the proliferation peak, by enhancing migration.


Assuntos
Transição Epitelial-Mesenquimal , Células-Tronco , Transição Epitelial-Mesenquimal/genética , Regulação para Baixo/genética , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , RNA Mensageiro/metabolismo
14.
Rev Esp Cardiol (Engl Ed) ; 75(12): 1011-1019, 2022 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35718066

RESUMO

INTRODUCTION AND OBJECTIVES: Heart failure (HF) is prevalent in advanced ages. Our objective was to assess the impact of frailty on 1-year mortality in older patients with ambulatory HF. METHODS: Our data come from the FRAGIC study (Spanish acronym for "Study of the impact of frailty and other geriatric syndromes on the clinical management and prognosis of elderly outpatients with heart failure"), a multicenter prospective registry conducted in 16 Spanish hospitals including outpatients ≥ 75 years with HF followed up by cardiology services in Spain. RESULTS: We included 499 patients with a mean age of 81.4±4.3 years, of whom 193 (38%) were women. A total of 268 (54%) had left ventricular ejection fraction <40%, and 84.6% was in NYHA II functional class. The FRAIL scale identified 244 (49%) pre-frail and 111 (22%) frail patients. Frail patients were significantly older, were more frequently female (both, P <.001), and had higher comorbidity according to the Charlson index (P=.017) and a higher prevalence of geriatric syndromes (P <.001). During a median follow-up of 371 [361-387] days, 58 patients (11.6%) died. On multivariate analysis (Cox regression model), frailty detected with the FRAIL scale was marginally associated with mortality (HR=2.35; 95%CI, 0.96-5.71; P=.059), while frailty identified by the visual mobility scale was an independent predictor of mortality (HR=2.26; 95%CI, 1.16-4.38; P=.015); this association was maintained after adjustment for confounding variables (HR=2.13; 95%CI, 1.08-4.20; P=.02). CONCLUSIONS: In elderly outpatients with HF, frailty is independently associated with mortality at 1 year of follow-up. It is essential to identify frailty as part of the comprehensive approach to elderly patients with HF.


Assuntos
Fragilidade , Insuficiência Cardíaca , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Masculino , Fragilidade/epidemiologia , Volume Sistólico , Idoso Fragilizado , Síndrome , Função Ventricular Esquerda , Estudos Prospectivos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Prognóstico , Doença Crônica , Avaliação Geriátrica
15.
Eur J Vasc Endovasc Surg ; 63(5): 751-758, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248436

RESUMO

OBJECTIVE: Abdominal aortic aneurysm (AAA) is characterised by the presence of B cells and immunoglobulins in the aortic wall, mainly in the adventitia. Kappa (κ) and lambda (λ) free light chains (FLCs) are produced from B cells during immunoglobulin synthesis. This study investigated the presence and prognostic value of combined FLCs (cFLCs or summed κ and λ) in patients with AAA. METHODS: cFLCs were analysed by a turbidimetric specific assay in tissue conditioned media from AAA samples (n = 34) compared with healthy aortas (n = 34) from France and in plasma samples from patients with AAA (n = 434) and age matched controls (n = 104) selected from the Viborg Vascular (VIVA) AAA screening trial in Denmark. t test, logistic regression, and Cox regression were used to test whether plasma cFLCs serve as a marker for AAA presence and whether cFLCs were predictive of death, major adverse cardiovascular events (MACE), or major adverse lower limb events (MALE). RESULTS: Increased cFLC levels were detected in the AAA adventitial layer compared with the AAA medial layer and healthy media layer (13.65 ± 3.17 vs. 6.57 ± 1.01 vs. 0.49 ± 0.09 mg/L, respectively, p < .050). The upper tertile of plasma cFLCs was independently associated with AAA presence after correcting for confounders (odds ratio [OR] 7.596, 95% confidence intervals [CI] 3.117 - 18.513; p < .001). Of 434 patients with AAA, 89 (20.5%) died, 104 (24.0%) suffered MACE, and 63 (14.5%) suffered MALE, during a five year follow up. In univariable analysis, the cFLC upper tertile was associated with a higher risk of death, MACE, and MALE (p < .001 for all). After adjustment for confounders, cFLCs remained an independent predictor of all cause mortality (hazard ratio [HR] 4.310, 95% CI 2.157 - 8.609; p < .001), MACE (HR 2.153, 95% CI 1.218 - 3.804; p = .008), or MALE (HR 3.442, 95% CI 1.548 - 7.652; p = .002) for those in the upper tertile. CONCLUSION: Increased cFLCs are observed in adventitial tissue of patients with AAA, indicating local activation of B cells. Plasma cFLC levels are an independent predictor of death, MACE, and MALE in patients with AAA.


Assuntos
Aneurisma da Aorta Abdominal , Aneurisma da Aorta Abdominal/cirurgia , Biomarcadores , Humanos , Cadeias Leves de Imunoglobulina , Modelos Logísticos , Prognóstico , Fatores de Risco
16.
Rev Esp Cardiol (Engl Ed) ; 75(7): 568-575, 2022 Jul.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34969644

RESUMO

INTRODUCTION AND OBJECTIVES: There are no in-depth studies of the long-term outcome of patients with syncope after exclusion of cardiac etiology. We therefore analyzed the long-term outcome of this population. METHODS: For 147 months, we included all patients with syncope referred to our syncope unit after exclusion of a cardiac cause. RESULTS: We included 589 consecutive patients. There were 313 (53.1%) women, and the median age was 52 [34-66] years. Of these, 405 (68.8%) were diagnosed with vasovagal syncope (VVS), 65 (11%) with orthostatic hypotension syncope (OHS), and 119 (20.2%) with syncope of unknown etiology (SUE). During a median follow-up of 52 [28-89] months, 220 (37.4%) had recurrences (21.7% ≥ 2 recurrences), and 39 died (6.6%). Syncope recurred in 41% of patients with VVS, 35.4% with OHS, and 25.2% with SUE (P=.006). In the Cox multivariate analysis, recurrence was correlated with age (P=.002), female sex (P <.0001), and the number of previous episodes (< 5 vs ≥ 5; P <.0001). Death occurred in 15 (3.5%) patients with VVS, 11 (16.9%) with OHS, and 13 (10.9%) with SUE (P=.001). In the multivariate analysis, death was associated with age (P=.0001), diabetes (P=.007), and diagnosis of OHS (P=.026) and SUE (P=.020). CONCLUSIONS: In patients with noncardiac syncope, the recurrence rate after 52 months of follow-up was 37.4% and mortality was 6.6% per year. Recurrence was higher in patients with a neuromedial profile and mortality was higher in patients with a nonneuromedial profile.


Assuntos
Síncope Vasovagal , Teste da Mesa Inclinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Síncope/epidemiologia , Síncope/etiologia , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/epidemiologia
17.
Eur J Cardiovasc Nurs ; 21(2): 116-126, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-34008849

RESUMO

AIMS: The assumption that improved self-care in the setting of heart failure (HF) care necessarily translates into improvements in long-term mortality and/or hospitalization is not well established. We aimed to study the association between self-care and long-term mortality and other major adverse HF events (MAHFE). METHODS AND RESULTS: We conducted an observational, prospective, cohort study of 1123 consecutive patients with chronic HF. The primary endpoint was all-cause mortality. We used the European Heart Failure Self-care Behaviour Scale 9-item version (EHFSCBS-9) to measure global self-care (overall score) and three specific dimensions of self-care including autonomy-based adherence, consulting behaviour and provider-based adherence. After a mean follow-up of 3.3 years, all-cause death occurred in 487 patients (43%). In adjusted analysis, higher EHFScBS-9 scores (better self-care) at baseline were associated with lower risk of all-cause death [hazard ratio (HR) 0.993, 95% confidence interval (CI) (0.988-0.997), P-value = 0.002], cardiovascular (CV) death [HR 0.989, 95% CI (0.981-0.996), P-value = 0.003], HF hospitalization [HR 0.993, 95% CI (0.988-0.998), P-value = 0.005], and the combination of MAHFE [HR 0.995, 95% CI (0.991-0.999), P-value = 0.018]. Similarly, impaired global self-care [HR 1.589, 95% CI (1.201-2.127), P-value = 0.001], impaired autonomy-based adherence [HR 1.464, 95% CI (1.114-1.923), P-value = 0.006], and impaired consulting behaviour dimensions [HR 1.510, 95% CI (1.140-1.923), P-value = 0.006] were all associated with higher risk of all-cause mortality. CONCLUSION: In this study, we have shown that worse self-care is an independent predictor of long-term mortality (both, all-cause and CV), HF hospitalization, and the combinations of these endpoints in patients with chronic HF. Important dimensions of self-care such as autonomy-based adherence and consulting behaviour also determine the risk of all these outcomes in the long term.


Assuntos
Insuficiência Cardíaca , Autocuidado , Estudos de Coortes , Insuficiência Cardíaca/terapia , Hospitalização , Humanos , Assistência de Longa Duração , Estudos Prospectivos
18.
Antioxidants (Basel) ; 10(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34943023

RESUMO

Diabetes mellitus (DM) is a high-impact disease commonly characterized by hyperglycemia, inflammation, and oxidative stress. Diabetic nephropathy (DN) is a common diabetic microvascular complication and the leading cause of chronic kidney disease worldwide. This study investigates the protective effects of the synthetic flavonoid hidrosmin (5-O-(beta-hydroxyethyl) diosmin) in experimental DN induced by streptozotocin injection in apolipoprotein E deficient mice. Oral administration of hidrosmin (300 mg/kg/day, n = 11) to diabetic mice for 7 weeks markedly reduced albuminuria (albumin-to-creatinine ratio: 47 ± 11% vs. control) and ameliorated renal pathological damage and expression of kidney injury markers. Kidneys of hidrosmin-treated mice exhibited lower content of macrophages and T cells, reduced expression of cytokines and chemokines, and attenuated inflammatory signaling pathways. Hidrosmin treatment improved the redox balance by reducing prooxidant enzymes and enhancing antioxidant genes, and also decreased senescence markers in diabetic kidneys. In vitro, hidrosmin dose-dependently reduced the expression of inflammatory and oxidative genes in tubuloepithelial cells exposed to either high-glucose or cytokines, with no evidence of cytotoxicity at effective concentrations. In conclusion, the synthetic flavonoid hidrosmin exerts a beneficial effect against DN by reducing inflammation, oxidative stress, and senescence pathways. Hidrosmin could have a potential role as a coadjutant therapy for the chronic complications of DM.

19.
Int J Mol Sci ; 22(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34638632

RESUMO

Cellular identity is determined through complex patterns of gene expression. Chromatin, the dynamic structure containing genetic information, is regulated through epigenetic modulators, mainly by the histone code. One of the main challenges for the cell is maintaining functionality and identity, despite the accumulation of DNA damage throughout the aging process. Replicative cells can remain in a senescent state or develop a malign cancer phenotype. In contrast, post-mitotic cells such as pyramidal neurons maintain extraordinary functionality despite advanced age, but they lose their identity. This review focuses on tau, a protein that protects DNA, organizes chromatin, and plays a crucial role in genomic stability. In contrast, tau cytosolic aggregates are considered hallmarks of Alzheimer´s disease (AD) and other neurodegenerative disorders called tauopathies. Here, we explain AD as a phenomenon of chromatin dysregulation directly involving the epigenetic histone code and a progressive destabilization of the tau-chromatin interaction, leading to the consequent dysregulation of gene expression. Although this destabilization could be lethal for post-mitotic neurons, tau protein mediates profound cellular transformations that allow for their temporal survival.


Assuntos
Doença de Alzheimer/metabolismo , Cromatina/metabolismo , Proteínas tau/metabolismo , Doença de Alzheimer/etiologia , Doença de Alzheimer/genética , Cromatina/genética , DNA/química , DNA/genética , DNA/metabolismo , Dano ao DNA , Epigênese Genética , Instabilidade Genômica , Código das Histonas , Humanos , Nucleossomos/metabolismo , Fosforilação , Fatores de Tempo , Proteínas tau/química , Proteínas tau/genética
20.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576182

RESUMO

C3G (RAPGEF1) is a guanine nucleotide exchange factor (GEF) for GTPases from the Ras superfamily, mainly Rap1, although it also acts through GEF-independent mechanisms. C3G regulates several cellular functions. It is expressed at relatively high levels in specific brain areas, playing important roles during embryonic development. Recent studies have uncovered different roles for C3G in cancer that are likely to depend on cell context, tumour type, and stage. However, its role in brain tumours remained unknown until very recently. We found that C3G expression is downregulated in GBM, which promotes the acquisition of a more mesenchymal phenotype, enhancing migration and invasion, but not proliferation. ERKs hyperactivation, likely induced by FGFR1, is responsible for this pro-invasive effect detected in C3G silenced cells. Other RTKs (Receptor Tyrosine Kinases) are also dysregulated and could also contribute to C3G effects. However, it remains undetermined whether Rap1 is a mediator of C3G actions in GBM. Various Rap1 isoforms can promote proliferation and invasion in GBM cells, while C3G inhibits migration/invasion. Therefore, other RapGEFs could play a major role regulating Rap1 activity in these tumours. Based on the information available, C3G could represent a new biomarker for GBM diagnosis, prognosis, and personalised treatment of patients in combination with other GBM molecular markers. The quantification of C3G levels in circulating tumour cells (CTCs) in the cerebrospinal liquid and/or circulating fluids might be a useful tool to improve GBM patient treatment and survival.


Assuntos
Glioblastoma/metabolismo , Fator 2 de Liberação do Nucleotídeo Guanina/metabolismo , Animais , Glioblastoma/genética , Fator 2 de Liberação do Nucleotídeo Guanina/genética , Humanos , Células Neoplásicas Circulantes/metabolismo , Proteínas rap1 de Ligação ao GTP/genética , Proteínas rap1 de Ligação ao GTP/metabolismo
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