RESUMO
Myocardial infarction is a major cause of premature death in adults. Compromised cardiac function after myocardial infarction leads to chronic heart failure with systemic health complications and a high mortality rate1. Effective therapeutic strategies are needed to improve the recovery of cardiac function after myocardial infarction. More specifically, there is a major unmet need for a new class of drugs that can improve cardiomyocyte contractility, because inotropic therapies that are currently available have been associated with high morbidity and mortality in patients with systolic heart failure2,3 or have shown a very modest reduction of risk of heart failure4. Microtubule detyrosination is emerging as an important mechanism for the regulation of cardiomyocyte contractility5. Here we show that deficiency of microtubule-affinity regulating kinase 4 (MARK4) substantially limits the reduction in the left ventricular ejection fraction after acute myocardial infarction in mice, without affecting infarct size or cardiac remodelling. Mechanistically, we provide evidence that MARK4 regulates cardiomyocyte contractility by promoting phosphorylation of microtubule-associated protein 4 (MAP4), which facilitates the access of vasohibin 2 (VASH2)-a tubulin carboxypeptidase-to microtubules for the detyrosination of α-tubulin. Our results show how the detyrosination of microtubules in cardiomyocytes is finely tuned by MARK4 to regulate cardiac inotropy, and identify MARK4 as a promising therapeutic target for improving cardiac function after myocardial infarction.
Assuntos
Insuficiência Cardíaca/fisiopatologia , Microtúbulos/química , Infarto do Miocárdio/fisiopatologia , Proteínas Serina-Treonina Quinases/fisiologia , Tirosina/química , Proteínas Angiogênicas , Animais , Carboxipeptidases , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos , Miócitos Cardíacos , Volume Sistólico , Função Ventricular EsquerdaRESUMO
The mitochondrial metabolite succinate is a key driver of ischemia/reperfusion injury (IRI). Targeting succinate metabolism by inhibiting succinate dehydrogenase (SDH) upon reperfusion using malonate is an effective therapeutic strategy to achieve cardioprotection in the short term (< 24 h reperfusion) in mouse and pig in vivo myocardial infarction (MI) models. We aimed to assess whether inhibiting IRI with malonate given upon reperfusion could prevent post-MI heart failure (HF) assessed after 28 days. Male C57BL/6 J mice were subjected to 30 min left anterior coronary artery (LAD) occlusion, before reperfusion for 28 days. Malonate or without-malonate control was infused as a single dose upon reperfusion. Cardiac function was assessed by echocardiography and fibrosis by Masson's trichrome staining. Reperfusion without malonate significantly reduced ejection fraction (~ 47%), fractional shortening (~ 23%) and elevated collagen deposition 28 days post-MI. Malonate, administered as a single infusion (16 mg/kg/min for 10 min) upon reperfusion, gave a significant cardioprotective effect, with ejection fraction (~ 60%) and fractional shortening (~ 30%) preserved and less collagen deposition. Using an acidified malonate formulation, to enhance its uptake into cardiomyocytes via the monocarboxylate transporter 1, both 1.6 and 16 mg/kg/min 10 min infusion led to robust long-term cardioprotection with preserved ejection fraction (> 60%) and fractional shortening (~ 30%), as well as significantly less collagen deposition than control hearts. Malonate administration upon reperfusion prevents post-MI HF. Acidification of malonate enables lower doses of malonate to also achieve long-term cardioprotection post-MI. Therefore, the administration of acidified malonate upon reperfusion is a promising therapeutic strategy to prevent IRI and post-MI HF.
Assuntos
Modelos Animais de Doenças , Insuficiência Cardíaca , Malonatos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Animais , Malonatos/farmacologia , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Insuficiência Cardíaca/prevenção & controle , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/etiologia , Camundongos , Miocárdio/metabolismo , Miocárdio/patologia , Função Ventricular Esquerda/efeitos dos fármacos , Fibrose , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Fatores de TempoRESUMO
Activation of the immune response during injury is a critical early event that determines whether the outcome of tissue restoration is regeneration or replacement of the damaged tissue with a scar. The mechanisms by which immune signals control these fundamentally different regenerative pathways are largely unknown. We have demonstrated that, during skin repair in mice, interleukin-4 receptor α (IL-4Rα)-dependent macrophage activation controlled collagen fibril assembly and that this process was important for effective repair while having adverse pro-fibrotic effects. We identified Relm-α as one important player in the pathway from IL-4Rα signaling in macrophages to the induction of lysyl hydroxylase 2 (LH2), an enzyme that directs persistent pro-fibrotic collagen cross-links, in fibroblasts. Notably, Relm-ß induced LH2 in human fibroblasts, and expression of both factors was increased in lipodermatosclerosis, a condition of excessive human skin fibrosis. Collectively, our findings provide mechanistic insights into the link between type 2 immunity and initiation of pro-fibrotic pathways.
Assuntos
Cicatriz/etiologia , Colágeno/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Macrófagos/metabolismo , Receptores de Superfície Celular/fisiologia , Transdução de Sinais/fisiologia , Cicatrização/fisiologia , Animais , Cicatriz/metabolismo , Cicatriz/patologia , Técnicas de Cocultura , Dermatite/metabolismo , Dermatite/patologia , Fibroblastos/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Interleucinas/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Microfibrilas/metabolismo , Microfibrilas/ultraestrutura , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/biossíntese , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Receptores de Superfície Celular/deficiência , Esclerodermia Localizada/metabolismo , Esclerodermia Localizada/patologia , Pele/lesões , Pele/metabolismo , Pele/patologiaRESUMO
BACKGROUND: Inhibiting SDH (succinate dehydrogenase), with the competitive inhibitor malonate, has shown promise in ameliorating ischemia/reperfusion injury. However, key for translation to the clinic is understanding the mechanism of malonate entry into cells to enable inhibition of SDH, its mitochondrial target, as malonate itself poorly permeates cellular membranes. The possibility of malonate selectively entering the at-risk heart tissue on reperfusion, however, remains unexplored. METHODS: C57BL/6J mice, C2C12 and H9c2 myoblasts, and HeLa cells were used to elucidate the mechanism of selective malonate uptake into the ischemic heart upon reperfusion. Cells were treated with malonate while varying pH or together with transport inhibitors. Mouse hearts were either perfused ex vivo (Langendorff) or subjected to in vivo left anterior descending coronary artery ligation as models of ischemia/reperfusion injury. Succinate and malonate levels were assessed by liquid chromatography-tandem mass spectrometry LC-MS/MS, in vivo by mass spectrometry imaging, and infarct size by TTC (2,3,5-triphenyl-2H-tetrazolium chloride) staining. RESULTS: Malonate was robustly protective against cardiac ischemia/reperfusion injury, but only if administered at reperfusion and not when infused before ischemia. The extent of malonate uptake into the heart was proportional to the duration of ischemia. Malonate entry into cardiomyocytes in vivo and in vitro was dramatically increased at the low pH (≈6.5) associated with ischemia. This increased uptake of malonate was blocked by selective inhibition of MCT1 (monocarboxylate transporter 1). Reperfusion of the ischemic heart region with malonate led to selective SDH inhibition in the at-risk region. Acid-formulation greatly enhances the cardioprotective potency of malonate. CONCLUSIONS: Cardioprotection by malonate is dependent on its entry into cardiomyocytes. This is facilitated by the local decrease in pH that occurs during ischemia, leading to its selective uptake upon reperfusion into the at-risk tissue, via MCT1. Thus, malonate's preferential uptake in reperfused tissue means it is an at-risk tissue-selective drug that protects against cardiac ischemia/reperfusion injury.
Assuntos
Traumatismo por Reperfusão Miocárdica , Animais , Cromatografia Líquida , Células HeLa , Humanos , Isquemia , Malonatos/farmacologia , Malonatos/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos , Espectrometria de Massas em TandemRESUMO
The term 'sclerosing diseases of the skin' comprises specific dermatological entities, which have fibrotic changes of the skin in common. These diseases mostly manifest in different clinical subtypes according to cutaneous and extracutaneous involvement and can sometimes be difficult to distinguish from each other. The present consensus provides an update to the 2017 European Dermatology Forum Guidelines, focusing on characteristic clinical and histopathological features, diagnostic scores and the serum autoantibodies most useful for differential diagnosis. In addition, updated strategies for the first- and advanced-line therapy of sclerosing skin diseases are addressed in detail. Part 2 of this consensus provides clinicians with an overview of the diagnosis and treatment of scleromyxoedema and scleroedema (of Buschke).
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Escleromixedema , Humanos , Escleromixedema/diagnóstico , Escleromixedema/patologia , Escleromixedema/terapia , Consenso , Diagnóstico DiferencialRESUMO
Magnesium-based biomaterials hold remarkable promise for various clinical applications, offering advantages such as reduced stress-shielding and enhanced bone strengthening and vascular remodeling compared to traditional materials. However, ensuring the quality of preclinical research is crucial for the development of these implants. To achieve implant success, an understanding of the cellular responses post-implantation, proper model selection, and good study design are crucial. There are several challenges to reaching a safe and effective translation of laboratory findings into clinical practice. The utilization of Mg-based biomedical devices eliminates the need for biomaterial removal surgery post-healing and mitigates adverse effects associated with permanent biomaterial implantation. However, the high corrosion rate of Mg-based implants poses challenges such as unexpected degradation, structural failure, hydrogen evolution, alkalization, and cytotoxicity. The biocompatibility and degradability of materials based on magnesium have been studied by many researchers in vitro; however, evaluations addressing the impact of the material in vivo still need to be improved. Several animal models, including rats, rabbits, dogs, and pigs, have been explored to assess the potential of magnesium-based materials. Moreover, strategies such as alloying and coating have been identified to enhance the degradation rate of magnesium-based materials in vivo to transform these challenges into opportunities. This review aims to explore the utilization of Mg implants across various biomedical applications within cellular (in vitro) and animal (in vivo) models.
Assuntos
Materiais Biocompatíveis , Magnésio , Magnésio/química , Animais , Materiais Biocompatíveis/química , Humanos , Projetos de Pesquisa , Teste de Materiais , Corrosão , Próteses e ImplantesRESUMO
The updated S2k guideline deals with the diagnosis and therapy of localized scleroderma (LoS). LoS represents a spectrum of sclerotic skin diseases in which, depending on the subtype and localisation, structures such as adipose tissue, muscles, joints, and bones may also be affected. Involvement of internal organs or progression to systemic sclerosis does not occur. LoS can be classified into four main forms: limited, generalized, linear, and mixed forms, with some additional subtypes. For cases of limited skin involvement, the guideline primarily recommends therapy with topical corticosteroids. UV therapy can also be recommended. In subtypes with severe skin or musculoskeletal involvement, systemic therapy with methotrexate is recommended. During the active phase of the disease, systemic glucocorticosteroids can be used additionally. In cases of methotrexate and steroid refractory courses, contraindications, or intolerance, mycophenolate mofetil, mycophenolic acid, or abatacept can be considered as second-line systemic therapies. In the case of linear LoS, autologous adipose-derived stem cell transplantation can also be performed for correcting soft tissue defects.
Assuntos
Fármacos Dermatológicos , Esclerodermia Localizada , Humanos , Metotrexato/uso terapêutico , Esclerodermia Localizada/diagnóstico , Esclerodermia Localizada/terapia , Pele , Fármacos Dermatológicos/uso terapêutico , Ácido Micofenólico/uso terapêuticoRESUMO
In the context of myocardial infarction, the burst of superoxide generated by reverse electron transport (RET) at complex I in mitochondria is a crucial trigger for damage during ischaemia/reperfusion (I/R) injury. Here we outline the necessary conditions for superoxide production by RET at complex I and how it can occur during reperfusion. In addition, we explore various pathways that are implicated in generating the conditions for RET to occur and suggest potential therapeutic strategies to target RET, aiming to achieve cardioprotection.
Assuntos
Infarto do Miocárdio , Traumatismo por Reperfusão , Humanos , Transporte de Elétrons , Superóxidos , Fosforilação Oxidativa , Mitocôndrias , Infarto do Miocárdio/prevenção & controleRESUMO
OBJECTIVES: Activation of fibroblasts is a hallmark of fibrotic processes. Besides cytokines and growth factors, fibroblasts are regulated by the extracellular matrix environment through receptors such as integrins, which transduce biochemical and mechanical signals enabling cells to mount appropriate responses according to biological demands. The aim of this work was to investigate the in vivo role of collagen-fibroblast interactions for regulating fibroblast functions and fibrosis. METHODS: Triple knockout (tKO) mice with a combined ablation of integrins α1ß1, α2ß1 and α11ß1 were created to address the significance of integrin-mediated cell-collagen communication. Properties of primary dermal fibroblasts lacking collagen-binding integrins were delineated in vitro. Response of the tKO mice skin to bleomycin induced fibrotic challenge was assessed. RESULTS: Triple integrin-deficient mice develop normally, are transiently smaller and reveal mild alterations in mechanoresilience of the skin. Fibroblasts from these mice in culture show defects in cytoskeletal architecture, traction stress generation, matrix production and organisation. Ablation of the three integrins leads to increased levels of discoidin domain receptor 2, an alternative receptor recognising collagens in vivo and in vitro. However, this overexpression fails to compensate adhesion and spreading defects on collagen substrates in vitro. Mice lacking collagen-binding integrins show a severely attenuated fibrotic response with impaired mechanotransduction, reduced collagen production and matrix organisation. CONCLUSIONS: The data provide evidence for a crucial role of collagen-binding integrins in fibroblast force generation and differentiation in vitro and for matrix deposition and tissue remodelling in vivo. Targeting fibroblast-collagen interactions might represent a promising therapeutic approach to regulate connective tissue deposition in fibrotic diseases.
RESUMO
OBJECTIVE: To evaluate the evidence concerning systemic pharmacological treatments for SSc digital ulcers (DUs) to inform the development of evidence-based treatment guidelines. METHODS: A systematic literature review of seven databases was performed to identify all original research studies of adult patients with SSc DUs. Randomized controlled trials (RCTs) and prospective longitudinal observational studies (OBSs) were eligible for inclusion. Data were extracted, applying the patient, intervention, comparison, outcome framework, and risk of bias (RoB) was assessed. Due to study heterogeneity, narrative summaries were used to present data. RESULTS: Forty-seven studies that evaluated the treatment efficacy or safety of pharmacological therapies were identified among 4250 references. Data from 18 RCTs of 1927 patients and 29 OBSs of 661 patients, at various RoB (total 2588 patients) showed that i.v. iloprost, phosphodiesterase-5 inhibitors and atorvastatin are effective for the treatment of active DUs. Bosentan reduced the rate of future DUs in two RCTs (moderate RoB) and eight OBSs at low to high RoB. Two small studies (moderate RoB) indicate that Janus kinase inhibitors may be effective for the treatment of active DUs, otherwise there are no data to support the use of immunosuppression or anti-platelet agents in the management of DUs. CONCLUSION: There are several systemic treatments, across four medication classes, that are effective therapies for the management of SSc DUs. However, a lack of robust data means it is not possible to define the optimal treatment regimen for SSc DUs. The relatively low quality of evidence available has highlighted further areas of research need.
Assuntos
Escleroderma Sistêmico , Úlcera Cutânea , Adulto , Humanos , Úlcera Cutânea/tratamento farmacológico , Úlcera Cutânea/etiologia , Dedos , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/tratamento farmacológico , Bosentana/uso terapêuticoRESUMO
Sjögren's syndrome (SS) is a systemic autoimmune disease that frequently occurs concomitantly with other systemic connective tissue disorders, including rare and complex diseases such as systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). The presence of SS influences the clinical expression of the other autoimmune diseases, thus offering the unique opportunity to explore the similarities in genetic signatures, as well as common environmental and biologic factors modulating the expression of disease phenotypes. In this review, we will specifically discuss the possibility of defining "SS/SLE" and "SS/SSc" as distinct subsets within the context of connective tissue diseases with different clinical expression and outcomes, thus deserving an individualised assessment and personalised medical interventions.
Assuntos
Doenças Autoimunes , Doenças do Tecido Conjuntivo , Lúpus Eritematoso Sistêmico , Escleroderma Sistêmico , Síndrome de Sjogren , Doenças do Tecido Conjuntivo/diagnóstico , Doenças do Tecido Conjuntivo/genética , Doenças do Tecido Conjuntivo/terapia , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/terapia , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/terapia , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/genética , Síndrome de Sjogren/terapiaRESUMO
The management of systemic sclerosis (SSc) is complex, evolving, and requires a multidisciplinary approach. At diagnosis and throughout the disease course, clinical assessment and monitoring of skin involvement is vital using the modified Rodnan Skin Score, patient-reported outcomes, and new global composite scores (such as the Combined Response Index for Systemic Sclerosis, which also considers lung function). Immunomodulation is the mainstay of skin fibrosis treatment, with mycophenolate mofetil considered first line. Meanwhile vasculopathy-related manifestations (Raynaud's phenomenon, digital ulcers) and calcinosis, require general measures combined with specific pharmacologic (calcium-channel blockers, phosphodiesterase type 5 inhibitors, and prostanoids), nonpharmacologic (digital sympathectomy and botulinum toxin injections), and often multifaceted, management approaches. Patients should be screened at the time of diagnosis specifically for systemic manifestations and then regularly thereafter, with appropriate treatment. Numerous targeted therapeutic options for SSc, including skin fibrosis, are emerging and include B-cell depletion, anti-interleukin 6, Janus kinase, and transforming growth factor ß inhibition. This second article in the continuing medical education series discusses these key aspects of SSc assessment and treatment, with particular focus on skin involvement. It is vital that dermatologists play a key role in the multidisciplinary approach to SSc management.
Assuntos
Toxinas Botulínicas , Doença de Raynaud , Escleroderma Sistêmico , Úlcera Cutânea , Adulto , Toxinas Botulínicas/uso terapêutico , Cálcio/uso terapêutico , Fibrose , Humanos , Janus Quinases , Ácido Micofenólico/uso terapêutico , Inibidores da Fosfodiesterase 5 , Prostaglandinas/uso terapêutico , Doença de Raynaud/tratamento farmacológico , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/terapia , Úlcera Cutânea/tratamento farmacológico , Fator de Crescimento Transformador betaRESUMO
Systemic sclerosis (SSc), also referred to as systemic scleroderma or scleroderma, is a rare, complex immune-mediated connective tissue disease characterized by progressive skin fibrosis and other clinically heterogenous features. The etiopathogenesis of SSc involves vasculopathy and immune system dysregulation occurring on a permissive genetic and epigenetic background, ultimately leading to fibrosis. Recent developments in our understanding of disease-specific autoantibodies and bioinformatic analyses has led to a reconsideration of the purely clinical classification of diffuse and limited cutaneous SSc subgroups. Autoantibody profiles are predictive of skin and internal organ involvement and disease course. Early diagnosis of SSc, with commencement of disease-modifying treatment, has the potential to improve patient outcomes. In SSc, many of the clinical manifestations that present early signs of disease progression and activity are cutaneous, meaning dermatologists can and should play a key role in the diagnosis and management of this significant condition. The first article in this continuing medical education series discusses the epidemiology, clinical characteristics, and pathogenesis of SSc in adults, with an emphasis on skin manifestations, the important role of dermatologists in recognizing these, and their correlation with systemic features and disease course.
Assuntos
Doenças do Tecido Conjuntivo , Esclerodermia Localizada , Escleroderma Sistêmico , Adulto , Autoanticorpos , Progressão da Doença , Fibrose , Humanos , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/etiologia , Escleroderma Sistêmico/terapiaRESUMO
PURPOSE: Mitochondrial reactive oxygen species (ROS) production upon reperfusion of ischemic tissue initiates the ischemia/reperfusion (I/R) injury associated with heart attack. During ischemia, succinate accumulates and its oxidation upon reperfusion by succinate dehydrogenase (SDH) drives ROS production. Inhibition of succinate accumulation and/or oxidation by dimethyl malonate (DMM), a cell permeable prodrug of the SDH inhibitor malonate, can decrease I/R injury. However, DMM is hydrolysed slowly, requiring administration to the heart prior to ischemia, precluding its administration to patients at the point of reperfusion, for example at the same time as unblocking a coronary artery following a heart attack. To accelerate malonate delivery, here we developed more rapidly hydrolysable malonate esters. METHODS: We synthesised a series of malonate esters and assessed their uptake and hydrolysis by isolated mitochondria, C2C12 cells and in mice in vivo. In addition, we assessed protection against cardiac I/R injury by the esters using an in vivo mouse model of acute myocardial infarction. RESULTS: We found that the diacetoxymethyl malonate diester (MAM) most rapidly delivered large amounts of malonate to cells in vivo. Furthermore, MAM could inhibit mitochondrial ROS production from succinate oxidation and was protective against I/R injury in vivo when added at reperfusion. CONCLUSIONS: The rapidly hydrolysed malonate prodrug MAM can protect against cardiac I/R injury in a clinically relevant mouse model.
Assuntos
Cardiotônicos/farmacologia , Malonatos/farmacologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Animais , Cardiotônicos/síntese química , Cardiotônicos/química , Linhagem Celular , Modelos Animais de Doenças , Ésteres/química , Feminino , Humanos , Masculino , Malonatos/síntese química , Malonatos/química , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Pró-Fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Ácido Succínico/metabolismoRESUMO
Our skin is continuously exposed to mechanical challenge, including shear, stretch, and compression. The extracellular matrix of the dermis is perfectly suited to resist these challenges and maintain integrity of normal skin even upon large strains. Fibroblasts are the key cells that interpret mechanical and chemical cues in their environment to turnover matrix and maintain homeostasis in the skin of healthy adults. Upon tissue injury, fibroblasts and an exclusive selection of other cells become activated into myofibroblasts with the task to restore skin integrity by forming structurally imperfect but mechanically stable scar tissue. Failure of myofibroblasts to terminate their actions after successful repair or upon chronic inflammation results in dysregulated myofibroblast activities which can lead to hypertrophic scarring and/or skin fibrosis. After providing an overview on the major fibrillar matrix components in normal skin, we will interrogate the various origins of fibroblasts and myofibroblasts in the skin. We then examine the role of the matrix as signaling hub and how fibroblasts respond to mechanical matrix cues to restore order in the confusing environment of a healing wound.
Assuntos
Cicatriz Hipertrófica , Cicatrização , Diferenciação Celular , Cicatriz Hipertrófica/patologia , Matriz Extracelular/patologia , Fibroblastos/patologia , Humanos , Miofibroblastos/patologia , Pele/patologia , Fator de Crescimento Transformador beta1RESUMO
With more than 25 million people affected, heart failure (HF) is a global threat. As energy production pathways are known to play a pivotal role in HF, we sought here to identify key metabolic changes in ischemic- and non-ischemic HF by using a multi-OMICS approach. Serum metabolites and mRNAseq and epigenetic DNA methylation profiles were analyzed from blood and left ventricular heart biopsy specimens of the same individuals. In total we collected serum from n = 82 patients with Dilated Cardiomyopathy (DCM) and n = 51 controls in the screening stage. We identified several metabolites involved in glycolysis and citric acid cycle to be elevated up to 5.7-fold in DCM (p = 1.7 × 10-6). Interestingly, cardiac mRNA and epigenetic changes of genes encoding rate-limiting enzymes of these pathways could also be found and validated in our second stage of metabolite assessment in n = 52 DCM, n = 39 ischemic HF and n = 57 controls. In conclusion, we identified a new set of metabolomic biomarkers for HF. We were able to identify underlying biological cascades that potentially represent suitable intervention targets.
Assuntos
Biomarcadores/metabolismo , Cardiomiopatia Dilatada/genética , Epigenômica/métodos , Perfilação da Expressão Gênica/métodos , Insuficiência Cardíaca/genética , Metabolômica/métodos , Adulto , Idoso , Biomarcadores/sangue , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/metabolismo , Estudos de Coortes , Epigênese Genética , Feminino , Glicólise/genética , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente PrincipalRESUMO
Reducing infarct size during a cardiac ischaemic-reperfusion episode is still of paramount importance, because the extension of myocardial necrosis is an important risk factor for developing heart failure. Cardiac ischaemia-reperfusion injury (IRI) is in principle a metabolic pathology as it is caused by abruptly halted metabolism during the ischaemic episode and exacerbated by sudden restart of specific metabolic pathways at reperfusion. It should therefore not come as a surprise that therapy directed at metabolic pathways can modulate IRI. Here, we summarize the current knowledge of important metabolic pathways as therapeutic targets to combat cardiac IRI. Activating metabolic pathways such as glycolysis (eg AMPK activators), glucose oxidation (activating pyruvate dehydrogenase complex), ketone oxidation (increasing ketone plasma levels), hexosamine biosynthesis pathway (O-GlcNAcylation; administration of glucosamine/glutamine) and deacetylation (activating sirtuins 1 or 3; administration of NAD+ -boosting compounds) all seem to hold promise to reduce acute IRI. In contrast, some metabolic pathways may offer protection through diminished activity. These pathways comprise the malate-aspartate shuttle (in need of novel specific reversible inhibitors), mitochondrial oxygen consumption, fatty acid oxidation (CD36 inhibitors, malonyl-CoA decarboxylase inhibitors) and mitochondrial succinate metabolism (malonate). Additionally, protecting the cristae structure of the mitochondria during IR, by maintaining the association of hexokinase II or creatine kinase with mitochondria, or inhibiting destabilization of FO F1 -ATPase dimers, prevents mitochondrial damage and thereby reduces cardiac IRI. Currently, the most promising and druggable metabolic therapy against cardiac IRI seems to be the singular or combined targeting of glycolysis, O-GlcNAcylation and metabolism of ketones, fatty acids and succinate.
Assuntos
Terapia de Alvo Molecular , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Animais , Metabolismo Energético , Humanos , Mitocôndrias Cardíacas/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/patologiaRESUMO
Cardiac ischaemia-reperfusion (I/R) injury has been attributed to stress signals arising from an impaired mitochondrial electron transport chain (ETC), which include redox imbalance, metabolic stalling and excessive production of reactive oxygen species (ROS). The alternative oxidase (AOX) is a respiratory enzyme, absent in mammals, that accepts electrons from a reduced quinone pool to reduce oxygen to water, thereby restoring electron flux when impaired and, in the process, blunting ROS production. Hence, AOX represents a natural rescue mechanism from respiratory stress. This study aimed to determine how respiratory restoration through xenotopically expressed AOX affects the re-perfused post-ischaemic mouse heart. As expected, AOX supports ETC function and attenuates the ROS load in post-anoxic heart mitochondria. However, post-ischaemic cardiac remodelling over 3 and 9 weeks was not improved. AOX blunted transcript levels of factors known to be up-regulated upon I/R such as the atrial natriuretic peptide (Anp) whilst expression of pro-fibrotic and pro-apoptotic transcripts were increased. Ex vivo analysis revealed contractile failure at nine but not 3 weeks after ischaemia whilst label-free quantitative proteomics identified an increase in proteins promoting adverse extracellular matrix remodelling. Together, this indicates an essential role for ETC-derived signals during cardiac adaptive remodelling and identified ROS as a possible effector.
Assuntos
Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Transdução de Sinais , Remodelação Ventricular , Animais , Biocatálise , Transporte de Elétrons , Matriz Extracelular/metabolismo , Masculino , Camundongos , Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/metabolismo , Contração Miocárdica , Isquemia Miocárdica/complicações , Isquemia Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/patologia , Miocárdio/ultraestrutura , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Due to the frequent presence of interstitial lung disease and widespread use of immunosuppressive treatment, systemic sclerosis (SSc) patients may be considered at risk for a more severe disease course and higher mortality when they develop Severe Acute Respiratory Syndrome - Coronavirus - 2 (SARS-CoV-2) virus infection. Therefore, with World Scleroderma Foundation endorsement, experts from different specialties including rheumatology, virology and clinical immunology gathered virtually to answer to the main practical clinical questions regarding SARS-CoV-2 infection coming from both patients and physicians. This preliminary advice is aligned with other national and international recommendations, adapted for SSc patients.
Assuntos
Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/fisiopatologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/fisiopatologia , Escleroderma Sistêmico/terapia , Escleroderma Sistêmico/virologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Betacoronavirus , COVID-19 , Infecções por Coronavirus/epidemiologia , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Doenças Pulmonares Intersticiais/imunologia , Doenças Pulmonares Intersticiais/virologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/virologia , SARS-CoV-2 , Escleroderma Sistêmico/epidemiologia , Escleroderma Sistêmico/imunologiaRESUMO
OBJECTIVES: Systemic sclerosis is a heterogeneous, multisystem disease. It can occur at any age, but most patients develop the disease between the age of 40 to 50 years. There is controversial evidence on whether/how the age at disease onset affects their clinical phenotype. We here investigate the relationship between age at disease onset and symptoms in a large cohort of SSc patients (lcSSc, dcSSc and SSc-overlap syndromes). METHODS: Clinical data of the registry of the German Network for Systemic Scleroderma including 3281 patients were evaluated and subdivided into three age groups at disease onset (<40 years, 40-60 years, >60 years). RESULTS: Among all SSc patients, 24.5% developed their first non-Raynaud phenomenon symptoms at the age <40 years, and 22.5% were older than 60 years of age. In particular, older patients at onset developed the lcSSc subset significantly more often. Furthermore, they had pulmonary hypertension more often, but digital ulcerations less often. Remarkably, the course of the disease was more rapidly progressing in the older cohort (>60 years), except for gastrointestinal and musculoskeletal involvement. No significant difference was found for the use of corticosteroids. However, significantly, fewer patients older than 60 years received immunosuppressive treatment. CONCLUSION: In this large registry, â¼25% of patients developed SSc at an age above 60 years with an increased frequency of lcSSc. In this age group, an onset of internal organ involvement was significantly accelerated across all three subsets. These findings suggest that, in the elderly cohort, more frequent follow-up examinations are required for an earlier detection of organ complications.