RESUMO
Obesity is characterized by low-grade inflammation, energy imbalance and impaired thermogenesis. The role of regulatory T cells (Treg) in inflammation-mediated maladaptive thermogenesis is not well established. Here, we find that the p38 pathway is a key regulator of T cell-mediated adipose tissue (AT) inflammation and browning. Mice with T cells specifically lacking the p38 activators MKK3/6 are protected against diet-induced obesity, leading to an improved metabolic profile, increased browning, and enhanced thermogenesis. We identify IL-35 as a driver of adipocyte thermogenic program through the ATF2/UCP1/FGF21 pathway. IL-35 limits CD8+ T cell infiltration and inflammation in AT. Interestingly, we find that IL-35 levels are reduced in visceral fat from obese patients. Mechanistically, we demonstrate that p38 controls the expression of IL-35 in human and mouse Treg cells through mTOR pathway activation. Our findings highlight p38 signaling as a molecular orchestrator of AT T cell accumulation and function.
Assuntos
Interleucinas , Obesidade , Linfócitos T Reguladores , Termogênese , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Interleucinas/metabolismo , Obesidade/metabolismo , Camundongos , Humanos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Inflamação/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
The cell cycle is a tightly regulated process that is controlled by the conserved cyclin-dependent kinase (CDK)-cyclin protein complex1. However, control of the G0-to-G1 transition is not completely understood. Here we demonstrate that p38 MAPK gamma (p38γ) acts as a CDK-like kinase and thus cooperates with CDKs, regulating entry into the cell cycle. p38γ shares high sequence homology, inhibition sensitivity and substrate specificity with CDK family members. In mouse hepatocytes, p38γ induces proliferation after partial hepatectomy by promoting the phosphorylation of retinoblastoma tumour suppressor protein at known CDK target residues. Lack of p38γ or treatment with the p38γ inhibitor pirfenidone protects against the chemically induced formation of liver tumours. Furthermore, biopsies of human hepatocellular carcinoma show high expression of p38γ, suggesting that p38γ could be a therapeutic target in the treatment of this disease.
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Carcinogênese/patologia , Ciclo Celular , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Fígado/enzimologia , Fígado/patologia , Proteína Quinase 12 Ativada por Mitógeno/metabolismo , Idoso , Animais , Carcinogênese/efeitos dos fármacos , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/metabolismo , Feminino , Hepatócitos/citologia , Hepatócitos/patologia , Humanos , Fígado/cirurgia , Neoplasias Hepáticas/induzido quimicamente , Masculino , Camundongos , Pessoa de Meia-Idade , Proteína Quinase 12 Ativada por Mitógeno/antagonistas & inibidores , Fosforilação , Piridonas/farmacologia , Proteína do Retinoblastoma/química , Proteína do Retinoblastoma/metabolismo , Homologia de Sequência , Especificidade por SubstratoRESUMO
During the first weeks of postnatal heart development, cardiomyocytes undergo a major adaptive metabolic shift from glycolytic energy production to fatty acid oxidation. This metabolic change is contemporaneous to the up-regulation and activation of the p38γ and p38δ stress-activated protein kinases in the heart. We demonstrate that p38γ/δ contribute to the early postnatal cardiac metabolic switch through inhibitory phosphorylation of glycogen synthase 1 (GYS1) and glycogen metabolism inactivation. Premature induction of p38γ/δ activation in cardiomyocytes of newborn mice results in an early GYS1 phosphorylation and inhibition of cardiac glycogen production, triggering an early metabolic shift that induces a deficit in cardiomyocyte fuel supply, leading to whole-body metabolic deregulation and maladaptive cardiac pathogenesis. Notably, the adverse effects of forced premature cardiac p38γ/δ activation in neonate mice are prevented by maternal diet supplementation of fatty acids during pregnancy and lactation. These results suggest that diet interventions have a potential for treating human cardiac genetic diseases that affect heart metabolism.
Assuntos
Glicogênio Sintase/metabolismo , Proteína Quinase 12 Ativada por Mitógeno/metabolismo , Proteína Quinase 13 Ativada por Mitógeno/metabolismo , Miocárdio/enzimologia , Animais , Animais Recém-Nascidos , Cardiomegalia/enzimologia , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Dieta Hiperlipídica , Ativação Enzimática , Comportamento Alimentar , Feminino , Deleção de Genes , Intolerância à Glucose/enzimologia , Glicogênio/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos , Sistema de Sinalização das MAP Quinases , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/enzimologia , Especificidade de Órgãos , FosforilaçãoRESUMO
Early diagnosis and treatment of chronic kidney disease (CKD) is a worldwide challenge. Subjects with albumin-to-creatinine ratio (ACR) ≥ 30 mg/g and preserved renal function are considered to be at no cardiorenal risk in clinical practice, but prospective clinical studies evidence increased risk, even at the high-normal (HN) ACR range (10-30 mg/g), supporting the need to identify other molecular indicators for early assessment of patients at higher risk. Following our previous studies, here we aim to stratify the normoalbuminuria range according to cardiorenal risk and identify the glycoproteins and N-glycosylation sites associated with kidney damage in subclinical CKD. Glycoproteins were analyzed in urine from hypertensive patients within the HN ACR range compared to control group (C; ACR < 10 mg/g) by mass spectrometry. A different cohort was analyzed for confirmation (ELISA) and sex perspective was evaluated. Patients' follow-up for 8 years since basal urine collection revealed higher renal function decline and ACR progression for HN patients. Differential N-glycopeptides and their N -glycosylation sites were also identified, together with their pathogenicity. N-glycosylation may condition pathological protein deregulation, and a panel of 62 glycoproteins evidenced alteration in normoalbuminuric subjects within the HN range. Haptoglobin-related protein, haptoglobin, afamin, transferrin, and immunoglobulin heavy constant gamma 1 (IGHG1) and 2 (IGHG2) showed increased levels in HN patients, pointing to disturbed iron metabolism and tubular reabsorption and supporting the tubule as a target of interest in the early progression of CKD. When analyzed separately, haptoglobin, afamin, transferrin, and IGHG2 remained significant in HN, in both women and men. At the peptide level, 172 N-glycopeptides showed differential abundance in HN patients, and 26 showed high pathogenicity, 10 of them belonging to glycoproteins that do not show variation between HN and C groups. This study highlights the value of glycosylation in subjects not meeting KDIGO criteria for CKD. The identified N-glycopeptides and glycosylation sites showed novel targets, for both the early assessment of individual cardiorenal risk and for intervention aimed at anticipating CKD progression.
Assuntos
Glicopeptídeos , Insuficiência Renal Crônica , Humanos , Masculino , Feminino , Glicopeptídeos/urina , Insuficiência Renal Crônica/urina , Pessoa de Meia-Idade , Glicosilação , Idoso , Biomarcadores/urina , Creatinina/urina , Glicoproteínas/urina , Progressão da Doença , Albuminúria/urina , Fatores de Risco , Haptoglobinas/metabolismoRESUMO
Heterotopic pregnancy refers to the simultaneous presence of ectopic pregnancy and intrauterine pregnancy. With the advent of assisted reproductive technology, the overall incidence of heterotopic pregnancies has risen. We report a case of a 36-year-old woman with type 2 diabetes mellitus and 1-year of primary infertility. Following oral ovulation induction cycles and intrauterine insemination, diagnosis of heterotopic cervical pregnancy was made by ultrasonography at 7.4 weeks of gestation. Laser ablation of the cervical pregnancy was performed achieving adequate homeostasis at the implantation site and preserving the intrauterine pregnancy. A healthy infant was delivered at 36 0/7 weeks by cesarean section. Laser ablation is a minimally invasive procedure that appears to lead to successful outcomes in the treatment of heterotopic cervical pregnancy.
Assuntos
Diabetes Mellitus Tipo 2 , Terapia a Laser , Gravidez Heterotópica , Adulto , Cesárea , Diabetes Mellitus Tipo 2/cirurgia , Feminino , Fertilização in vitro , Humanos , Gravidez , Gravidez Heterotópica/diagnóstico por imagem , Gravidez Heterotópica/cirurgiaRESUMO
The coordinated behavior of proteins is central to systems biology. However, the underlying mechanisms are poorly known and methods to analyze coordination by conventional quantitative proteomics are still lacking. We present the Systems Biology Triangle (SBT), a new algorithm that allows the study of protein coordination by pairwise quantitative proteomics. The Systems Biology Triangle detected statistically significant coordination in diverse biological models of very different nature and subjected to different kinds of perturbations. The Systems Biology Triangle also revealed with unprecedented molecular detail an array of coordinated, early protein responses in vascular smooth muscle cells treated at different times with angiotensin-II. These responses included activation of protein synthesis, folding, turnover, and muscle contraction - consistent with a differentiated phenotype-as well as the induction of migration and the repression of cell proliferation and secretion. Remarkably, the majority of the altered functional categories were protein complexes, interaction networks, or metabolic pathways. These changes could not be detected by other algorithms widely used by the proteomics community, and the vast majority of proteins involved have not been described before to be regulated by AngII. The unique capabilities of The Systems Biology Triangle to detect functional protein alterations produced by the coordinated action of proteins in pairwise quantitative proteomics experiments make this algorithm an attractive choice for the biological interpretation of results on a routine basis.
Assuntos
Proteoma/análise , Proteômica/métodos , Biologia de Sistemas/métodos , Algoritmos , Animais , Ensaios de Triagem em Larga Escala , Humanos , Mapas de Interação de ProteínasRESUMO
BACKGROUND: Calcific aortic stenosis (CAS) is the most common heart valve disease in the elderly, representing an important economic and social burden in developed countries. Currently, there is no way to predict either the onset or progression of CAS, emphasizing the need to identify useful biomarkers for this condition. METHODS: We performed a multi-proteomic analysis on different kinds of samples from CAS patients and healthy donors: tissue, secretome and plasma. The results were validated in an independent cohort of subjects by immunohistochemistry, western blotting and selected reaction monitoring. RESULTS: Alpha 1 antichymotrypsin (AACT) abundance was altered in the CAS samples, as confirmed in the validation phase. The significant changes observed in the amounts of this protein strongly suggest that it could be involved in the molecular mechanisms underlying CAS. In addition, our results suggest there is enhanced release of AACT into the extracellular fluids when the disease commences. CONCLUSIONS: The significant increase of AACT in CAS patients suggests it fulfils an important role in the physiopathology of this disease. These results permit us to propose that AACT may serve as a potential marker for the diagnosis of CAS, with considerable clinical value.
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In many plant species, an exposure to a sublethal temperature triggers an adaptative response called acclimation. This response involves an extensive molecular reprogramming that allows the plant to further survive to an otherwise lethal increase of temperature. A related response is also launched under an abrupt and lethal heat stress that, in this case, is unable to successfully promote thermotolerance and therefore ends up in plant death. Although these molecular programmes are expected to have common players, the overlapping degree and the specific regulators of each process are currently unknown. We have carried out a high-throughput comparative proteomics analysis during acclimation and during the early stages of the plant response to a severe heat stress that lead Arabidopsis seedlings either to survival or death. This analysis dissects these responses, unravels the common players and identifies the specific proteins associated with these different fates. Thermotolerance assays of mutants in genes with an uncharacterized role in heat stress demonstrate the relevance of this study to uncover both positive and negative heat regulators and pinpoint a pivotal role of JR1 and BAG6 in heat tolerance.
Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Proteoma/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Western Blotting , Resposta ao Choque Térmico/fisiologia , Temperatura Alta , Proteoma/metabolismoRESUMO
Abdominal aortic aneurysm (AAA) is a permanent dilation of the aorta due to excessive proteolytic, oxidative and inflammatory injury of the aortic wall. We aimed to identify novel mediators involved in AAA pathophysiology, which could lead to novel therapeutic approaches. For that purpose, plasma from four AAA patients and four controls were analysed by a label-free proteomic approach. Among identified proteins, paraoxonase-1 (PON1) was decreased in plasma of AAA patients compared with controls, which was further validated in a bigger cohort of samples by ELISA. The phenylesterase enzymatic activity of PON1 was also decreased in serum of AAA patients compared with controls. To address the potential role of PON1 as a mediator of AAA, experimental AAA was induced by aortic elastase perfusion in wild-type (WT) mice and human transgenic PON1 (HuTgPON1) mice. Similar to humans, PON1 activity was also decreased in serum of elastase-induced AAA mice compared with healthy mice. Interestingly, overexpression of PON1 was accompanied by smaller aortic dilation and higher elastin and vascular smooth muscle cell (VSMC) content in the AAA of HuTgPON1 compared with WT mice. Moreover, HuTgPON1 mice display decreased oxidative stress and apoptosis, as well as macrophage infiltration and monocyte chemoattractant protein-1 (MCP1) expression, in elastase-induced AAA. In conclusion, decreased circulating PON1 activity is associated with human and experimental AAA. PON1 overexpression in mice protects against AAA progression by reducing oxidative stress, apoptosis and inflammation, suggesting that strategies aimed at increasing PON1 activity could prevent AAA.
Assuntos
Aneurisma da Aorta Abdominal/metabolismo , Arildialquilfosfatase/metabolismo , Animais , Aneurisma da Aorta Abdominal/prevenção & controle , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Humanos , Inflamação/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Proteômica/métodosRESUMO
BACKGROUND: HIV-1 replication results in mitochondrial damage that is enhanced during antiretroviral therapy (ART). The onset of HIV-1 replication is regulated by viral protein Tat, a 101-residue protein codified by two exons that elongates viral transcripts. Although the first exon of Tat (aa 1-72) forms itself an active protein, the presence of the second exon (aa 73-101) results in a more competent transcriptional protein with additional functions. RESULTS: Mitochondrial overall functions were analyzed in Jurkat cells stably expressing full-length Tat (Tat101) or one-exon Tat (Tat72). Representative results were confirmed in PBLs transiently expressing Tat101 and in HIV-infected Jurkat cells. The intracellular expression of Tat101 induced the deregulation of metabolism and cytoskeletal proteins which remodeled the function and distribution of mitochondria. Tat101 reduced the transcription of the mtDNA, resulting in low ATP production. The total amount of mitochondria increased likely to counteract their functional impairment. These effects were enhanced when Tat second exon was expressed. CONCLUSIONS: Intracellular Tat altered mtDNA transcription, mitochondrial content and distribution in CD4+ T cells. The importance of Tat second exon in non-transcriptional functions was confirmed. Tat101 may be responsible for mitochondrial dysfunctions found in HIV-1 infected patients.
Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , DNA Mitocondrial/genética , HIV-1/fisiologia , Mitocôndrias/ultraestrutura , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/ultraestrutura , Citoesqueleto/patologia , Citoesqueleto/virologia , DNA Mitocondrial/metabolismo , Éxons , Glicólise , Humanos , Células Jurkat , Leucócitos Mononucleares , Mitocôndrias/genéticaRESUMO
One of the major challenges in cardiovascular medicine is to identify candidate biomarker proteins. Secretome analysis is particularly relevant in this search as it focuses on a subset of proteins released by a cell or tissue under certain conditions. The sample can be considered as a plasma subproteome and it provides a more direct approximation to the in vivo situation. Degenerative aortic stenosis is the most common worldwide cause of valve replacement. Using a proteomic analysis of the secretome from aortic stenosis valves we could identify candidate markers related to this pathology, which may facilitate early diagnosis and treatment. For this purpose, we have designed a method to validate the origin of secreted proteins, demonstrating their synthesis and release by the tissue and ruling out blood origin. The nLC-MS/MS analysis showed the labeling of 61 proteins, 82% of which incorporated the label in only one group. Western blot and selective reaction monitoring differential analysis, revealed a notable role of the extracellular matrix. Variation in particular proteins such as PEDF, cystatin and clusterin emphasizes the link between aortic stenosis and atherosclerosis. In particular, certain proteins variation in secretome levels correlates well, not only with label incorporation trend (only labeled in aortic stenosis group) but, more importantly, with alterations found in plasma from an independent cohort of samples, pointing to specific candidate markers to follow up in diagnosis, prognosis, and therapeutic intervention.
Assuntos
Estenose da Valva Aórtica/metabolismo , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Proteínas da Matriz Extracelular/metabolismo , Mediadores da Inflamação/metabolismo , Peptídeo Hidrolases/metabolismo , Idoso , Estenose da Valva Aórtica/sangue , Western Blotting , Feminino , Humanos , Marcação por Isótopo , Masculino , Espectrometria de Massas , Mapas de Interação de Proteínas , Proteoma/classificação , Proteoma/metabolismo , Proteômica , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
The objective of the study was to develop evidence-based and practical recommendations for the detection and management of comorbidity in patients with rheumatoid arthritis (RA) in daily practice. We used a modified RAND/UCLA methodology and systematic review (SR). The process map and specific recommendations, based on the SR, were established in discussion groups. A two round Delphi survey permitted (1) to prioritize the recommendations, (2) to refine them, and (3) to evaluate their agreement by a large group of users. The recommendations cover: (1) which comorbidities should be investigated in clinical practice at the first and following visits (including treatments, risk factors and patient's features that might interfere with RA management); (2) how and when should comorbidities and risk factors be investigated; (3) how to manage specific comorbidities, related or non-related to RA, including major adverse events of RA treatment, and to promote health (general and musculoskeletal health); and (4) specific recommendations to assure an integral care approach for RA patients with any comorbidity, such as health care models for chronic inflammatory patients, early arthritis units, relationships with primary care, specialized nursing care, and self-management. These recommendations are intended to guide rheumatologists, patients, and other stakeholders, on the early diagnosis and management of comorbidity in RA, in order to improve disease outcomes.
Assuntos
Artrite Reumatoide/epidemiologia , Guias de Prática Clínica como Assunto , Amiloidose/diagnóstico , Amiloidose/epidemiologia , Amiloidose/terapia , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Ansiedade/terapia , Artrite Reumatoide/terapia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/terapia , Comorbidade , Técnica Delphi , Depressão/diagnóstico , Depressão/epidemiologia , Depressão/terapia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Gerenciamento Clínico , Humanos , Infecções/diagnóstico , Infecções/epidemiologia , Infecções/terapia , Pneumopatias/diagnóstico , Pneumopatias/epidemiologia , Pneumopatias/terapia , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/terapia , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/terapia , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/terapia , Reumatologia/normas , Fumar/epidemiologia , Fumar/terapiaRESUMO
HIV-1 replication is efficiently controlled by the regulator protein Tat (101 amino acids) and codified by two exons, although the first exon (1-72 amino acids) is sufficient for this process. Tat can be released to the extracellular medium, acting as a soluble pro-apoptotic factor in neighboring cells. However, HIV-1-infected CD4(+) T lymphocytes show a higher resistance to apoptosis. We observed that the intracellular expression of Tat delayed FasL-mediated apoptosis in both peripheral blood lymphocytes and Jurkat cells, as it is an essential pathway to control T cell homeostasis during immune activation. Jurkat-Tat cells showed impairment in the activation of caspase-8, deficient release of mitochondrial cytochrome c, and delayed activation of both caspase-9 and -3. This protection was due to a profound deregulation of proteins that stabilized the mitochondrial membrane integrity, such as heat shock proteins, prohibitin, or nucleophosmin, as well as to the up-regulation of NF-κB-dependent anti-apoptotic proteins, such as BCL2, c-FLIPS, XIAP, and C-IAP2. These effects were observed in Jurkat expressing full-length Tat (Jurkat-Tat101) but not in Jurkat expressing the first exon of Tat (Jurkat-Tat72), proving that the second exon, and particularly the NF-κB-related motif ESKKKVE, was necessary for Tat-mediated protection against FasL apoptosis. Accordingly, the protection exerted by Tat was independent of its function as a regulator of both viral transcription and elongation. Moreover, these data proved that HIV-1 could have developed strategies to delay FasL-mediated apoptosis in infected CD4(+) T lymphocytes through the expression of Tat, thus favoring the persistent replication of HIV-1 in infected T cells.
Assuntos
Apoptose , Linfócitos T CD4-Positivos/virologia , Regulação da Expressão Gênica , HIV-1/metabolismo , Receptor fas/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Éxons , Humanos , Células Jurkat , Mitocôndrias/metabolismo , Mutagênese Sítio-Dirigida , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteoma , Proteômica/métodos , TransfecçãoRESUMO
Osteoarthritis (OA) is considered the most prevalent form of arthritis. The aim of this study was to verify potential protein OA biomarkers by applying Selected Reaction Monitoring (SRM) assays to protein extracts obtained from Bone Marrow-Mesenchymal Stem Cells (BM-MSCs) isolated from OA patients. BM aspirates were obtained from the femoral channel of OA patients at the time of surgery and from the femoral channel of hip fracture subjects without OA during hip joint replacement surgery for the treatment of subcapital fracture. SRM results verified the differential expression of several protein biomarkers in BM-MSCs from OA patients.
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We report the synthesis of micellar phosphatidylcholine-coated superparamagnetic iron oxide nanoparticles as a new long circulation contrast agents for magnetic resonance imaging. Oleic acid-coated Fe3 O4 nanoparticles were first prepared through thermal degradation and then encapsulated into small clusters with a phosphatidylcholine coating to obtain hydrophilic nanomicelles. A thorough characterization confirmed the chemical nature of the coating and the excellent colloidal stability of these nanomicelles in aqueous media. Magnetization and relaxivity properties proved their suitability as magnetic resonance imaging (MRI) contrast agent and in vitro cell viability data showed low toxicity. Vascular lifetime and elimination kinetics in the liver were assessed by blood relaxometry and by in vivo MRI in rats and compared with "control" particles prepared with a polyethylene glycol derivative. These micellar particles had a lifetime in blood of more than 10â h, much longer than the control nanoparticles (≈2â h), which is remarkable considering that the coating molecule is a small biocompatible zwitterionic phospholipid. The protein corona was characterized after incubation with rat serum at different times by high-throughput proteomics, showing a higher proportion of bound apolipoproteins and other dysopsonins for the phosphatidylcholine particles. The antibiofouling properties of this corona and its resistance to the adsorption of proteins corroborate the observed enhanced stability and prolonged systemic circulation.
Assuntos
Meios de Contraste/química , Compostos Férricos/química , Nanopartículas de Magnetita/química , Fosfatidilcolinas/química , Animais , Linhagem Celular , Meios de Contraste/farmacocinética , Compostos Férricos/sangue , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos C57BL , Micelas , Fosfatidilcolinas/sangue , Ratos , Ratos WistarRESUMO
Skeletal muscle has gained recognition as an endocrine organ releasing myokines upon contraction during physical exercise. These myokines exert both local and pleiotropic health benefits, underscoring the crucial role of muscle function in countering obesity and contributing to the overall positive effects of exercise on health. Here, we found that exercise activates muscle p38γ, increasing locomotor activity through the secretion of interleukin-15 (IL-15). IL-15 signals in the motor cortex, stimulating locomotor activity. This activation of muscle p38γ, leading to an increase locomotor activity, plays a crucial role in reducing the risk of diabetes and liver steatosis, unveiling a vital muscle-brain communication pathway with profound clinical implications. The correlation between p38γ activation in human muscle during acute exercise and increased blood IL-15 levels highlights the potential therapeutic relevance of this pathway in treating obesity and metabolic diseases. These findings provide valuable insights into the molecular basis of exercise-induced myokine responses promoting physical activity.
Assuntos
Exercício Físico , Interleucina-15 , Músculo Esquelético , Interleucina-15/metabolismo , Músculo Esquelético/metabolismo , Humanos , Animais , Exercício Físico/fisiologia , Locomoção , Camundongos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Masculino , Sistema de Sinalização das MAP Quinases , Obesidade/metabolismoRESUMO
Pulmonary hypertension (PH) can affect both pulmonary arterial tree and cardiac function, often leading to right heart failure and death. Despite the urgency, the lack of understanding has limited the development of effective cardiac therapeutic strategies. Our research reveals that MCJ modulates mitochondrial response to chronic hypoxia. MCJ levels elevate under hypoxic conditions, as in lungs of patients affected by COPD, mice exposed to hypoxia, and myocardium from pigs subjected to right ventricular (RV) overload. The absence of MCJ preserves RV function, safeguarding against both cardiac and lung remodeling induced by chronic hypoxia. Cardiac-specific silencing is enough to protect against cardiac dysfunction despite the adverse pulmonary remodeling. Mechanistically, the absence of MCJ triggers a protective preconditioning state mediated by the ROS/mTOR/HIF-1α axis. As a result, it preserves RV systolic function following hypoxia exposure. These discoveries provide a potential avenue to alleviate chronic hypoxia-induced PH, highlighting MCJ as a promising target against this condition.
Assuntos
Hipertensão Pulmonar , Animais , Humanos , Camundongos , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/tratamento farmacológico , Hipóxia , Pulmão , Miocárdio , Artéria Pulmonar , SuínosRESUMO
Exposure of many cancer cells, including multiple myeloma cells, to cytotoxic concentrations of natural products celastrol and withaferin A or synthetic compounds of the IHSF series resulted in denaturation of a luciferase reporter protein. Proteomic analysis of detergent-insoluble extract fractions from HeLa-derived cells revealed that withaferin A, IHSF058 and IHSF115 caused denaturation of 915, 722 and 991 of 5132 detected cellular proteins, respectively, of which 440 were targeted by all three compounds. Western blots showed that important fractions of these proteins, in some cases approaching half of total protein amounts, unfolded. Relatively indiscriminate covalent modification of target proteins was observed; 1178 different proteins were modified by IHSF058. Further illustrating the depth of the induced proteostasis crisis, only 13% of these proteins detectably aggregated, and 79% of the proteins that aggregated were not targets of covalent modification. Numerous proteostasis network components were modified and/or found in aggregates. Proteostasis disruption caused by the study compounds may be more profound than that mediated by proteasome inhibitors. The compounds act by a different mechanism that may be less susceptible to resistance development. Multiple myeloma cells were particularly sensitive to the compounds. Development of an additional proteostasis-disrupting therapy of multiple myeloma is suggested.
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Oxidative stress-induced myocardial apoptosis and necrosis are critically involved in ischemic infarction, and several sources of extracellular vesicles appear to be enriched in therapeutic activities. The central objective was to identify and validate the differential exosome miRNA repertoire in human cardiac progenitor cells (CPC). CPC exosomes were first analyzed by LC-MS/MS and compared by RNAseq with exomes of human mesenchymal stromal cells and human fibroblasts to define their differential exosome miRNA repertoire (exo-miRSEL). Proteomics demonstrated a highly significant representation of cardiovascular development functions and angiogenesis in CPC exosomes, and RNAseq analysis yielded about 350 different miRNAs; among the exo-miRSEL population, miR-935 was confirmed as the miRNA most significantly up-regulated; interestingly, miR-935 was also found to be preferentially expressed in mouse primary cardiac Bmi1+high CPC, a population highly enriched in progenitors. Furthermore, it was found that transfection of an miR-935 antagomiR combined with oxidative stress treatment provoked a significant increment both in apoptotic and necrotic populations, whereas transfection of a miR-935 mimic did not modify the response. Conclusion. miR-935 is a highly differentially expressed miRNA in exo-miRSEL, and its expression reduction promotes oxidative stress-associated apoptosis. MiR-935, together with other exosomal miRNA members, could counteract oxidative stress-related apoptosis, at least in CPC surroundings.
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(1) Objective:To assess the spectrum of PET-CT-related large vessel vasculitis (LVV) in a Spanish tertiary center and to determine whether FDG uptake by PET-CT differs between giant cell arteritis (GCA) with predominant cranial or extracranial phenotypes. (2) Methods: The spectrum of patients diagnosed with LVV by PET-CT in a tertiary referral hospital that cares for 450,000 people over a period of two years was reviewed. Moreover, differences in FDG uptake between LVV-GCA with predominantly cranial and extracranial phenotype were analyzed. (3) Results: Eighty patients were diagnosed with LVV by PET-CT. Most were due to systemic vasculitis (n = 64; 80%), especially GCA (n = 54; 67.5%). Other conditions included the presence of rheumatic diseases (n = 4; 3.2%), tumors (n = 9; 7.2%) and infections (n = 3; 2.4%). LVV-GCA patients with predominant extracranial GCA phenotype were younger (mean ± SD: 68.07 ± 9.91 vs. 75.46 ± 7.64 years; p = 0.017) and had a longer delay to the diagnosis (median [interquartile range] 12 [4-18] vs. 4 [3-8]; p = 0.006), but had polymyalgia rheumatica symptoms more frequently than those with predominantly cranial GCA phenotype (46.3% vs. 15.4%, p = 0.057). When FDG uptake was compared according to the two different disease patterns, no statistically significant differences were observed. However, patients with extracranial LVV-GCA showed a non-significantly higher frequency of vasculitic involvement of lower-extremity arteries. (4) Conclusions: Regardless of the predominant phenotype, LVV identified by PET-CT is more commonly due to GCA in the Spanish population. In these GCA patients, younger age, PMR, and a higher frequency of lower-extremity artery vasculitis suggest the presence of LVV.