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BACKGROUND: Defects of mitophagy, the selective form of autophagy for mitochondria, are commonly observed in several cardiovascular diseases and represent the main cause of mitochondrial dysfunction. For this reason, mitophagy has emerged as a novel and potential therapeutic target. METHODS: In this review, we discuss current evidence about the biological significance of mitophagy in relevant preclinical models of cardiac and vascular diseases, such as heart failure, ischemia/reperfusion injury, metabolic cardiomyopathy and atherosclerosis. RESULTS: Multiple studies have shown that cardiac and vascular mitophagy is an adaptive mechanism in response to stress, contributing to cardiovascular homeostasis. Mitophagy defects lead to cell death, ultimately impairing cardiac and vascular function, whereas restoration of mitophagy by specific compounds delays disease progression. CONCLUSIONS: Despite previous efforts, the molecular mechanisms underlying mitophagy activation in response to stress are not fully characterized. A comprehensive understanding of different forms of mitophagy active in the cardiovascular system is extremely important for the development of new drugs targeting this process. Human studies evaluating mitophagy abnormalities in patients at high cardiovascular risk also represent a future challenge.
Assuntos
Doenças Cardiovasculares , Mitofagia , Humanos , Mitofagia/fisiologia , Aterosclerose , Insuficiência Cardíaca/fisiopatologia , Animais , Traumatismo por Reperfusão Miocárdica , Cardiomiopatias/fisiopatologia , Mitocôndrias Cardíacas/metabolismoRESUMO
Mitochondrial dysfunction, causing increased reactive oxygen species (ROS) production, is a molecular feature of heart failure (HF). A defective antioxidant response and mitophagic flux were reported in circulating leucocytes of patients with chronic HF and reduced ejection fraction (HFrEF). Atrial natriuretic peptide (ANP) exerts many cardiac beneficial effects, including the ability to protect cardiomyocytes by promoting autophagy. We tested the impact of ANP on autophagy/mitophagy, altered mitochondrial structure and function and increased oxidative stress in HFrEF patients by both ex vivo and in vivo approaches. The ex vivo study included thirteen HFrEF patients whose peripheral blood mononuclear cells (PBMCs) were isolated and treated with αANP (10-11 M) for 4 h. The in vivo study included six HFrEF patients who received sacubitril/valsartan for two months. PBMCs were characterized before and after treatment. Both approaches analyzed mitochondrial structure and functionality. We found that levels of αANP increased upon sacubitril/valsartan, whereas levels of NT-proBNP decreased. Both the ex vivo direct exposure to αANP and the higher αANP level upon in vivo treatment with sacubitril/valsartan caused: (i) improvement of mitochondrial membrane potential; (ii) stimulation of the autophagic process; (iii) significant reduction of mitochondrial mass-index of mitophagy stimulation-and upregulation of mitophagy-related genes; (iv) reduction of mitochondrial damage with increased inner mitochondrial membrane (IMM)/outer mitochondrial membrane (OMM) index and reduced ROS generation. Herein we demonstrate that αANP stimulates both autophagy and mitophagy responses, counteracts mitochondrial dysfunction, and damages ultimately reducing mitochondrial oxidative stress generation in PBMCs from chronic HF patients. These properties were confirmed upon sacubitril/valsartan administration, a pivotal drug in HFrEF treatment.
Assuntos
Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/tratamento farmacológico , Fator Natriurético Atrial , Tetrazóis/farmacologia , Tetrazóis/uso terapêutico , Mitofagia , Leucócitos Mononucleares , Espécies Reativas de Oxigênio , Volume Sistólico , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Valsartana/farmacologia , Valsartana/uso terapêutico , MitocôndriasRESUMO
Heart failure is a major side effect of doxorubicin (DOX) treatment in patients with cancer. However, the mechanisms underlying the development of DOX-induced heart failure need to be addressed. This study aims to test whether the serine/threonine kinase MST1, a major Hippo pathway component, contributes to the development of DOX-induced myocardial injury. C57BL/6J WT mice and mice with cardiomyocyte-specific dominant-negative MST1 (kinase-dead) overexpression received three weekly injections of DOX, reaching a final cumulative dose of 18 mg/kg. Echocardiographic, histological and biochemical analyses were performed six weeks after the first DOX administration. The effects of MST1 inhibition on DOX-induced cardiomyocyte injury were also tested in vitro. MST1 signaling was significantly activated in cardiomyocytes in response to DOX treatment in vitro and in vivo. Wild-type (WT) mice treated with DOX developed cardiac dysfunction and mitochondrial abnormalities. However, these detrimental effects were abolished in mice with cardiomyocyte-specific overexpression of dominant-negative MST1 (DN-MST1) or treated with XMU-MP-1, a specific MST1 inhibitor, indicating that MST1 inhibition attenuates DOX-induced cardiac dysfunction. DOX treatment led to a significant downregulation of cardiac levels of SIRT3, a deacetylase involved in mitochondrial protection, in WT mice, which was rescued by MST1 inhibition. Pharmacological inhibition of SIRT3 blunted the protective effects of MST1 inhibition, indicating that SIRT3 downregulation mediates the cytotoxic effects of MST1 activation in response to DOX treatment. Finally, we found a significant upregulation of MST1 and downregulation of SIRT3 levels in human myocardial tissue of cancer patients treated with DOX. In summary, MST1 contributes to DOX-induced cardiomyopathy through SIRT3 downregulation.
Assuntos
Cardiomiopatias , Cardiopatias , Insuficiência Cardíaca , Sirtuína 3 , Humanos , Camundongos , Animais , Sirtuína 3/genética , Regulação para Baixo , Camundongos Endogâmicos C57BL , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Miócitos Cardíacos/metabolismo , Doxorrubicina/farmacologia , Cardiopatias/metabolismo , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , ApoptoseRESUMO
BACKGROUND: A dysfunction of NADH dehydrogenase, the mitochondrial Complex I (CI), associated with the development of left ventricular hypertrophy (LVH) in previous experimental studies. A deficiency of Ndufc2 (subunit of CI) impairs CI activity causing severe mitochondrial dysfunction. The T allele at NDUFC2/rs11237379 variant associates with reduced gene expression and impaired mitochondrial function. The present study tested the association of both NDUFC2/rs11237379 and NDUFC2/rs641836 variants with LVH in hypertensive patients. In vitro studies explored the impact of reduced Ndufc2 expression in isolated cardiomyocytes. METHODS: Two-hundred-forty-six subjects (147 male, 59.7%), with a mean age of 59 ± 15 years, were included for the genetic association analysis. Ndufc2 silencing was performed in both H9c2 and rat primary cardiomyocytes to explore the hypertrophy development and the underlying signaling pathway. RESULTS: The TT genotype at NDUFC2/rs11237379 associated with significantly reduced gene expression. Multivariate analysis revealed that patients carrying this genotype showed significant differences for septal thickness (p = 0.07), posterior wall thickness (p = 0.008), RWT (p = 0.021), LV mass/BSA (p = 0.03), compared to subjects carrying either CC or CT genotypes. Patients carrying the A allele at NDUFC2/rs641836 showed significant differences for septal thickness (p = 0.017), posterior wall thickness (p = 0.011), LV mass (p = 0.003), LV mass/BSA (p = 0.002) and LV mass/height2.7(p = 0.010) after adjustment for covariates. In-vitro, the Ndufc2 deficiency-dependent mitochondrial dysfunction caused cardiomyocyte hypertrophy, pointing to SIRT3-AMPK-AKT-MnSOD as a major underlying signaling pathway. CONCLUSIONS: We demonstrated for the first time a significant association of NDUFC2 variants with LVH in human hypertension and highlight a key role of Ndufc2 deficiency-dependent CI mitochondrial dysfunction on increased susceptibility to cardiac hypertrophy development.
Assuntos
Cardiomegalia , Hipertensão , Humanos , Masculino , Ratos , Animais , Adulto , Pessoa de Meia-Idade , Idoso , Cardiomegalia/genética , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/complicações , Hipertensão/complicações , Hipertensão/genética , Genótipo , Transdução de Sinais , Complexo I de Transporte de Elétrons/genéticaRESUMO
The compromised viability and function of cardiovascular cells are rescued by small molecules of triazole derivatives (Tzs), identified as 3a and 3b, by preventing mitochondrial dysfunction. The oxidative phosphorylation improves the respiratory control rate in the presence of Tzs independently of the substrates that energize the mitochondria. The F1FO-ATPase, the main candidate in mitochondrial permeability transition pore (mPTP) formation, is the biological target of Tzs and hydrophilic F1 domain of the enzyme is depicted as the binding region of Tzs. The protective effect of Tz molecules on isolated mitochondria was corroborated by immortalized cardiomyocytes results. Indeed, mPTP opening was attenuated in response to ionomycin. Consequently, increased mitochondrial roundness and reduction of both length and interconnections between mitochondria. In in-vitro and ex-vivo models of cardiovascular pathologies (i.e., hypoxia-reoxygenation and hypertension) were used to evaluate the Tzs cardioprotective action. Key parameters of porcine aortic endothelial cells (pAECs) oxidative metabolism and cell viability were not affected by Tzs. However, in the presence of either 1 µM 3a or 0.5 µM 3b the impaired cell metabolism of pAECs injured by hypoxia-reoxygenation was restored to control respiratory profile. Moreover, endothelial cells isolated from SHRSP exposed to high-salt treatment rescued the Complex I activity and the endothelial capability to form vessel-like tubes and vascular function in presence of Tzs. As a result, the specific biochemical mechanism of Tzs to block Ca2+-activated F1FO-ATPase protected cell viability and preserved the pAECs bioenergetic metabolism upon hypoxia-reoxygenation injury. Moreover, SHRSP improved vascular dysfunction in response to a high-salt treatment.
Assuntos
Doenças Cardiovasculares , Proteínas de Transporte da Membrana Mitocondrial , Animais , Suínos , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/farmacologia , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Células Endoteliais/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Hipóxia/metabolismoRESUMO
BACKGROUND AND AIMS: Trehalose, spermidine, nicotinamide, and polyphenols are natural substances that exert pro-autophagic and antioxidant properties. Their role in blood pressure (BP) regulation and preservation of vascular function in essential hypertension is unknown. The aim of this study was to evaluate the effect of a mixture of these agents on BP level, markers of oxidative stress, autophagy, endothelial function, and vascular stiffness in outpatients with grade 1 uncomplicated essential hypertension. METHODS AND RESULTS: A single-centre, open-label, case-control, pilot study was conducted in adult outpatients (aged ≥18 years) receiving or not the mixture for two months along with the standard therapies. Both at baseline and at the end of the treatment the following clinical parameters were evaluated: brachial seated office BP level, central aortic pressure, pulse wave velocity, augmentation index (AI@75). Both at baseline and at the end of the treatment, a blood sample was drawn for the measurement of: H2O2, HBA%, levels of sNOX2-dp, Atg 5, P62, endothelin 1, and NO bioavailability. The mixture of nutraceuticals did not influence BP levels. Patients receiving the mixture showed a significant decrease of oxidative stress, stimulation of autophagy, increased NO bioavailability and no increase of the AI@75, in contrast to what observed in hypertensive patients not receiving the mixture. CONCLUSIONS: The supplementation of the trehalose, spermidine, nicotinamide, and polyphenols mixture counteracted hypertension-related arterial stiffness through mechanisms likely dependent on oxidative stress downregulation and autophagy stimulation. These natural activators of autophagy may represent favourable adjuvants for prevention of the hypertensive cardiovascular damage.
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Stroke represents a main cause of death and permanent disability worldwide. In the attempt to develop targeted preventive and therapeutic strategies, several efforts were performed over the last decades to identify the specific molecular abnormalities preceding cerebral ischemia and neuronal death. In this regard, mitochondrial dysfunction, autophagy, and intracellular calcium homeostasis appear important contributors to stroke development, as underscored by recent pre-clinical evidence. Intracellular calcium (Ca2+) homeostasis is regulated, among other mechanisms, by the calcium sensor stromal interaction molecule 1 (STIM1) and calcium release-activated calcium modulator (ORAI) members, which mediate the store-operated Ca2+ entry (SOCE). The activity of SOCE is deregulated in animal models of ischemic stroke, leading to ischemic injury exacerbation. We found a different pattern of expression of few SOCE components, dependent from a STIM1 mutation, in cerebral endothelial cells isolated from the stroke-prone spontaneously hypertensive rat (SHRSP), compared to the stroke-resistant (SHRSR) strain, suggesting a potential involvement of this mechanism into the stroke predisposition of SHRSP. In this article, we discuss the relevant role of STIM1 in experimental stroke, as highlighted by the current literature and by our recent experimental findings, and the available evidence in the human disease. We also provide a glance on future perspectives and clinical implications of STIM1.
Assuntos
Proteínas de Neoplasias/metabolismo , Acidente Vascular Cerebral/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , HumanosRESUMO
Stroke is a leading cause of death and disability worldwide. Several mechanisms are involved in the pathogenesis of ischemic stroke (IS). The contributory role of the inflammatory and immunity processes was demonstrated both in vitro and in animal models, and was confirmed in humans. IS evokes an immediate inflammatory response that involves complex cellular and molecular mechanisms. All components of the innate and adaptive immunity systems are involved in several steps of the ischemic cascade. In the early phase, inflammatory and immune mechanisms contribute to the brain tissue damage, whereas, in the late phase, they participate to the tissue repair processes. In particular, damage-associated molecular patterns (DAMPs) appear critical for the promotion of altered blood brain barrier permeability, leukocytes infiltration, tissue edema and brain injury. Conversely, the activation of regulatory T lymphocytes (Tregs) plays protective effects. The identification of specific cellular/molecular elements belonging to the inflammatory and immune responses, contributing to the brain ischemic injury and tissue remodeling, offers the advantage to design adequate therapeutic strategies. In this article, we will present an overview of the knowledge on inflammatory and immunity processes in IS, with a particular focus on the role of DAMPs and leukocytes infiltration. We will discuss evidence obtained in preclinical models of IS and in humans. The main molecular mechanisms useful for the development of novel therapeutic approaches will be highlighted. The translation of experimental findings to the human disease is still a difficult step to pursue. Further investigations are required to fill up the existing gaps.
Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Humanos , Inflamação , Leucócitos , Modelos Animais , Acidente Vascular Cerebral/patologiaRESUMO
Cerebrovascular disease, a frequent complication of hypertension, is a major public health issue for which novel therapeutic and preventive approaches are needed. Autophagy activation is emerging as a potential therapeutic and preventive strategy toward stroke. Among usual activators of autophagy, the natural disaccharide trehalose (TRE) has been reported to be beneficial in preclinical models of neurodegenerative diseases, atherosclerosis and myocardial infarction. In this study, we tested for the first time the effects of TRE in the stroke-prone spontaneously hypertensive rat (SHRSP) fed with a high-salt stroke permissive diet (JD). We found that TRE reduced stroke occurrence and renal damage in high salt-fed SHRSP. TRE was also able to decrease systolic blood pressure. Through ex-vivo studies, we assessed the beneficial effect of TRE on the vascular function of high salt-fed SHRSP. At the molecular level, TRE restored brain autophagy and reduced mitochondrial mass, along with the improvement of mitochondrial function. The beneficial effects of TRE were associated with increased nuclear translocation of TFEB, a transcriptional activator of autophagy. Our results suggest that TRE may be considered as a natural compound efficacious for the prevention of hypertension-related target organ damage, with particular regard to stroke and renal damage.
Assuntos
Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Trealose/uso terapêutico , Animais , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Hipertensão/tratamento farmacológico , Hipertensão/genética , Hipertensão/metabolismo , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Mitofagia/efeitos dos fármacos , NADPH Oxidases/genética , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Endogâmicos SHR , Sódio na Dieta/administração & dosagem , Trealose/farmacologia , Fator de Necrose Tumoral alfa/genéticaRESUMO
The natriuretic peptides (NPs) family, including a class of hormones and their receptors, is largely known for its beneficial effects within the cardiovascular system to preserve regular functions and health. The concentration level of each component of the family is of crucial importance to guarantee a proper control of both systemic and local cardiovascular functions. A fine equilibrium between gene expression, protein secretion and clearance is needed to achieve the final optimal level of NPs. To this aim, the regulation of gene expression and translation plays a key role. In this regard, we know the existence of fine regulatory mechanisms, the so-called epigenetic mechanisms, which target many genes at either the promoter or the 3'UTR region to inhibit or activate their expression. The gene encoding ANP (NPPA) is regulated by histone modifications, DNA methylation, distinct microRNAs and a natural antisense transcript (NPPA-AS1) with consequent implications for both health and disease conditions. Notably, ANP modulates microRNAs on its own. Histone modifications of BNP gene (NPPB) are associated with several cardiomyopathies. The proBNP processing is regulated by miR30-GALNT1/2 axis. Among other components of the NPs family, CORIN, NPRA, NPRC and NEP may undergo epigenetic regulation. A better understanding of the epigenetic control of the NPs family will allow to gain more insights on the pathological basis of common cardiovascular diseases and to identify novel therapeutic targets. The present review article aims to discuss the major achievements obtained so far with studies on the epigenetic modulation of the NPs family.
Assuntos
Fator Natriurético Atrial/genética , Doença/genética , Regulação da Expressão Gênica/genética , Peptídeos Natriuréticos/genética , Animais , Epigênese Genética , Humanos , MicroRNAs/genética , Procainamida/análogos & derivados , Processamento de Proteína Pós-Traducional/genética , Receptores do Fator Natriurético AtrialRESUMO
AIMS: Low-grade endotoxaemia is detectable in human circulation but its role in thrombosis is still unclear. METHODS AND RESULTS: We measured serum lipopolysaccharide (LPS) concentration, soluble P-selectin (sP-selectin), a marker of platelet activation, and zonulin, a marker of gut permeability, in peripheral circulation, coronary thrombi, and intracoronary blood of patients with ST-elevation myocardial infarction (STEMI, n = 50) and stable angina (SA) (n = 50), respectively, and in controls (n = 50). Experimental study was carried out in mice to assess if Escherichia coli-LPS (E. coli-LPS) possess thrombotic property. Coronary thrombi from STEMI showed higher concentrations of LPS, sP-selectin vs. intracoronary blood of SA and peripheral blood of controls (P < 0.001). Zonulin was higher in STEMI compared to the other two groups [4.57 (3.34-5.22); 2.56 (0.41-4.36); 1.95 (1.22-2.65) ng/mL; P < 0.001] and correlated with LPS (Rs = 0.585; P < 0.001). Escherichia coli DNA was positive in 34% of STEMI vs. 12% of SA and 4% of controls (P < 0.001). In a subgroup of 12 STEMI, immunohistochemical analysis of coronary thrombi showed positivity for leucocyte Toll-like receptor 4 (TLR4), cathepsin G, and LPS from E. coli in 100%, 80%, and 25% of samples, respectively. E. coli-LPS injected in mice to reach LPS concentrations like those detected in coronary thrombi was associated with enhanced artery thrombosis and platelet activation, an effect blunted by TLR4 inhibitor co-administration. In vitro study demonstrated that LPS from E. coli enhanced platelet aggregation via TLR4-mediated leucocyte cathepsin G activation. CONCLUSION: ST-elevation myocardial infarction patients disclose an enhanced gut permeability that results in LPS translocation in human circulation and eventually thrombus growth at site of artery lesion via leucocyte-platelet interaction.
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Endotoxemia , Infarto do Miocárdio , Trombose , Receptor 4 Toll-Like , Animais , Artérias , Escherichia coli , Humanos , CamundongosRESUMO
AIMS: Here, we aimed to determine the therapeutic effect of longevity-associated variant (LAV)-BPIFB4 gene therapy on atherosclerosis. METHODS AND RESULTS: ApoE knockout mice (ApoE-/-) fed a high-fat diet were randomly allocated to receive LAV-BPIFB4, wild-type (WT)-BPIFB4, or empty vector via adeno-associated viral vector injection. The primary endpoints of the study were to assess (i) vascular reactivity and (ii) atherosclerotic disease severity, by Echo-Doppler imaging, histology and ultrastructural analysis. Moreover, we assessed the capacity of the LAV-BPIFB4 protein to shift monocyte-derived macrophages of atherosclerotic mice and patients towards an anti-inflammatory phenotype. LAV-BPIFB4 gene therapy rescued endothelial function of mesenteric and femoral arteries from ApoE-/- mice; this effect was blunted by AMD3100, a CXC chemokine receptor type 4 (CXCR4) inhibitor. LAV-BPIFB4-treated mice showed a CXCR4-mediated shift in the balance between Ly6Chigh/Ly6Clow monocytes and M2/M1 macrophages, along with decreased T cell proliferation and elevated circulating levels of interleukins IL-23 and IL-27. In vitro conditioning with LAV-BPIFB4 protein of macrophages from atherosclerotic patients resulted in a CXCR4-dependent M2 polarization phenotype. Furthermore, LAV-BPIFB4 treatment of arteries explanted from atherosclerotic patients increased the release of atheroprotective IL-33, while inhibiting the release of pro-inflammatory IL-1ß, inducing endothelial nitric oxide synthase phosphorylation and restoring endothelial function. Finally, significantly lower plasma BPIFB4 was detected in patients with pathological carotid stenosis (>25%) and intima media thickness >2 mm. CONCLUSION: Transfer of the LAV of BPIFB4 reduces the atherogenic process and skews macrophages towards an M2-resolving phenotype through modulation of CXCR4, thus opening up novel therapeutic possibilities in cardiovascular disease.
Assuntos
Aterosclerose , Placa Aterosclerótica , Idoso , Animais , Apolipoproteínas E , Aterosclerose/genética , Espessura Intima-Media Carotídea , Feminino , Humanos , Inflamação , Peptídeos e Proteínas de Sinalização Intercelular , Longevidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Fosfoproteínas , Receptores CXCR4RESUMO
Alterations in the metabolism of sphingolipids, a class of biologically active molecules in cell membranes with direct effect on vascular homeostasis, are increasingly recognized as important determinant in different vascular disorders. However, it is not clear whether sphingolipids are implicated in the pathogenesis of hypertension-related cerebrovascular and renal damage. In this study, we evaluated the existence of possible abnormalities related to the sphingolipid metabolism in the brain and kidneys of two well validated spontaneously hypertensive rat strains, the stroke-prone (SHRSP) and the stroke-resistant (SHRSR) models, as compared to the normotensive Wistar Kyoto (WKY) rat strain. Our results showed a global alteration in the metabolism of sphingolipids in both cerebral and renal tissues of both hypertensive strains as compared to the normotensive rat. However, few defects, such as reduced expression of enzymes involved in the metabolism/catabolism of sphingosine-1-phosphate and in the de novo biosynthetic pathways, were exclusively detected in the SHRSP. Although further studies are necessary to fully understand the significance of these findings, they suggest that defects in specific lipid molecules and/or their related metabolic pathways may likely contribute to the pathogenesis of hypertensive target organ damage and may eventually serve as future therapeutic targets to reduce the vascular consequences of hypertension.
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Lesões Encefálicas/metabolismo , Encéfalo/metabolismo , Hipertensão/metabolismo , Nefropatias/metabolismo , Rim/metabolismo , Lisofosfolipídeos/metabolismo , Esfingosina/análogos & derivados , Animais , Encéfalo/patologia , Lesões Encefálicas/patologia , Hipertensão/patologia , Rim/patologia , Nefropatias/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Esfingosina/metabolismoRESUMO
The mTOR (mechanistic target of rapamycin) is a master regulator of several crucial cellular processes, including protein synthesis, cellular growth, proliferation, autophagy, lysosomal function, and cell metabolism. mTOR interacts with specific adaptor proteins to form 2 multiprotein complexes, called mTORC1 (mTOR complex 1) and mTORC2 (mTOR complex 2). In the cardiovascular system, the mTOR pathway regulates both physiological and pathological processes in the heart. It is needed for embryonic cardiovascular development and for maintaining cardiac homeostasis in postnatal life. Studies involving mTOR loss-of-function models revealed that mTORC1 activation is indispensable for the development of adaptive cardiac hypertrophy in response to mechanical overload. mTORC2 is also required for normal cardiac physiology and ensures cardiomyocyte survival in response to pressure overload. However, partial genetic or pharmacological inhibition of mTORC1 reduces cardiac remodeling and heart failure in response to pressure overload and chronic myocardial infarction. In addition, mTORC1 blockade reduces cardiac derangements induced by genetic and metabolic disorders and has been reported to extend life span in mice. These studies suggest that pharmacological targeting of mTOR may represent a therapeutic strategy to confer cardioprotection, although clinical evidence in support of this notion is still scarce. This review summarizes and discusses the new evidence on the pathophysiological role of mTOR signaling in the cardiovascular system.
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Fenômenos Fisiológicos Cardiovasculares , Transdução de Sinais , Serina-Treonina Quinases TOR/fisiologia , Adaptação Fisiológica , Animais , Autofagia , Cardiomegalia/fisiopatologia , Sobrevivência Celular , Metabolismo Energético , Regulação da Expressão Gênica , Cardiopatias/tratamento farmacológico , Cardiopatias/enzimologia , Cardiopatias/fisiopatologia , Humanos , Hipóxia/metabolismo , Metabolismo dos Lipídeos , Mamíferos/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/deficiência , Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/deficiência , Alvo Mecanístico do Complexo 2 de Rapamicina/fisiologia , Camundongos , Mitocôndrias/metabolismo , Modelos Cardiovasculares , Biogênese de Organelas , Biossíntese de Proteínas , Estresse MecânicoRESUMO
The downregulation of uncoupling protein-2 (UCP2) is associated with increased brain and kidney injury in stroke-prone spontaneously hypertensive rats (SHRSP) fed with a Japanese style hypersodic diet (JD). Systemic overexpression of UCP2 reduces organ damage in JD-fed SHRSP. We examined the effect of brain-specific UCP2 overexpression on blood pressure (BP), stroke occurrence and kidney damage in JD-fed SHRSP. Rats received a single i.c.v. injection of a lentiviral vector encoding UCP2 (LV-UCP2), or an empty vector. The brain delivery of LV-UCP2 significantly delayed the occurrence of stroke and kidney damage. The large reduction of proteinuria observed after LV-UCP2 injection was unexpected, because BP levels were unchanged. At the time of stroke, rats treated with LV-UCP2 still showed a large UCP2 upregulation in the striatum, associated with increases in OPA1 and FIS1 protein levels, and reductions in PGC1-α, SOD2, TNFα mRNA levels and NRF2 protein levels. This suggested UCP2 overexpression enhanced mitochondrial fusion and fission and reduced oxidative damage and inflammation in the striatum of JD-fed SHRSP rats. Our data suggest the existence of central mechanisms that may protect against hypertension-induced organ damage independently of BP, and strengthen the suitability of strategies aimed at enhancing UCP2 expression for the treatment of hypertensive damage.
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Corpo Estriado/metabolismo , Hipertensão/terapia , Nefropatias/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Proteína Desacopladora 2/genética , Animais , Vetores Genéticos/administração & dosagem , Hipertensão/induzido quimicamente , Hipertensão/complicações , Hipertensão/metabolismo , Nefropatias/etiologia , Nefropatias/metabolismo , Lentivirus/genética , Masculino , Dinâmica Mitocondrial , Estresse Oxidativo , Ratos , Ratos Endogâmicos SHR , Sódio na Dieta/efeitos adversos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/metabolismo , Proteína Desacopladora 2/metabolismoRESUMO
Cardiovascular diseases (CVDs) such as hypertension, atherosclerosis, myocardial infarction, and diabetes are a significant public health problem worldwide. Although several novel pharmacological treatments to reduce the progression of CVDs have been discovered during the last 20 years, the better way to contain the onset of CVDs remains prevention. In this regard, nutraceuticals seem to own a great potential in maintaining human health, exerting important protective cardiovascular effects. In the last years, there has been increased focus on identifying natural compounds with cardiovascular health-promoting effects and also to characterize the molecular mechanisms involved. Although many review articles have focused on the individual natural compound impact on cardiovascular diseases, the aim of this manuscript was to examine the role of the most studied nutraceuticals, such as resveratrol, cocoa, quercetin, curcumin, brassica, berberine and Spirulina platensis, on different CVDs.
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Produtos Biológicos/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Suplementos Nutricionais , Saúde/normas , Berberina/administração & dosagem , Berberina/uso terapêutico , Produtos Biológicos/administração & dosagem , Brassica/química , Curcumina/administração & dosagem , Curcumina/uso terapêutico , Quercetina/administração & dosagem , Quercetina/uso terapêutico , Resveratrol/administração & dosagem , Resveratrol/uso terapêutico , Spirulina/químicaRESUMO
Despite important advances in diagnosis and treatment, heart failure (HF) remains a syndrome with substantial morbidity and dismal prognosis. Although implementation and optimization of existing technologies and drugs may lead to better management of HF, new or alternative strategies are desirable. In this regard, basic science is expected to give fundamental inputs, by expanding the knowledge of the pathways underlying HF development and progression, identifying approaches that may improve HF detection and prognostic stratification, and finding novel treatments. Here, we discuss recent basic science insights that encompass major areas of translational research in HF and have high potential clinical impact.
Assuntos
Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/terapia , Animais , Autofagia , Gerenciamento Clínico , Sistemas de Liberação de Medicamentos , Predisposição Genética para Doença , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Humanos , Inflamação/diagnóstico , Inflamação/genética , Inflamação/patologia , Inflamação/terapia , Itália , Microbiota , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Prognóstico , Sociedades Médicas , Pesquisa Translacional BiomédicaRESUMO
Bicuspid aortic valve (BAV) is a common congenital heart malformation frequently associated with the development of aortic valve diseases and severe aortopathy, such as aortic dilatation, aneurysm and dissection. To date, different genetic loci have been identified in syndromic and non- syndromic forms of BAV. Among these, genes involved in the regulation of extracellular matrix remodelling, epithelial to mesenchymal transition and nitric oxide metabolism appear to be the main contributors to BAV pathogenesis. However, no- single gene model explains BAV inheritance, suggesting that more factors are simultaneously involved. In this regard, characteristic epigenetic and immunological profiles have been documented to contradistinguish BAV individuals. In this review, we provide a comprehensive overview addressing molecular mechanisms involved in BAV development and progression.
Assuntos
Doenças da Aorta/patologia , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas/patologia , Animais , Valva Aórtica/fisiopatologia , Doença da Válvula Aórtica Bicúspide , Progressão da Doença , Doenças das Valvas Cardíacas/fisiopatologia , HumanosRESUMO
Ndufc2, a subunit of the NADH: ubiquinone oxidoreductase, plays a key role in the assembly and activity of complex I within the mitochondrial OXPHOS chain. Its deficiency has been shown to be involved in diabetes, cancer and stroke. To improve our knowledge on the mechanisms underlying the increased disease risk due to Ndufc2 reduction, we performed the present in vitro study aimed at the fine characterization of the derangements in mitochondrial structure and function consequent to Ndufc2 deficiency. We found that both fibroblasts obtained from skin of heterozygous Ndufc2 knock-out rat model showed marked mitochondrial dysfunction and PBMC obtained from subjects homozygous for the TT genotype of the rs11237379/NDUFC2 variant, previously shown to associate with reduced gene expression, demonstrated increased generation of reactive oxygen species and mitochondrial damage. The latter was associated with increased oxidative stress and significant ultrastructural impairment of mitochondrial morphology with a loss of internal cristae. In both models the exposure to stress stimuli, such as high-NaCl concentration or LPS, exacerbated the mitochondrial damage and dysfunction. Resveratrol significantly counteracted the ROS generation. These findings provide additional insights on the role of an altered pattern of mitochondrial structure-function as a cause of human diseases. In particular, they contribute to underscore a potential genetic risk factor for cardiovascular diseases, including stroke.
Assuntos
Complexo I de Transporte de Elétrons/deficiência , Mitocôndrias/enzimologia , Animais , Complexo I de Transporte de Elétrons/metabolismo , Fibroblastos/enzimologia , Fibroblastos/patologia , Fibroblastos/ultraestrutura , Humanos , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/metabolismo , Erros Inatos do Metabolismo/metabolismo , Mitocôndrias/patologia , Doenças Mitocondriais/enzimologia , Proteínas Mitocondriais/deficiência , Proteínas Mitocondriais/metabolismo , Oxirredução , Fosforilação Oxidativa , Estresse Oxidativo/fisiologia , Subunidades Proteicas , Ratos , Ratos Endogâmicos SHR , Espécies Reativas de Oxigênio/metabolismo , Acidente Vascular Cerebral/metabolismo , Ubiquinona/metabolismoRESUMO
Estrogens play a role in the patho-physiology of the prostate. In the present work we studied the effects of nonylphenol (NP), a xenoestrogen, on human adenocarcinoma prostate cells (LNCaP). In order to understand molecular and cellular involvement, we observed the effects on cell cycle and we investigated the expression and the cellular localization of estrogen receptors and gene expression of cyclin D1, ki-67, c-myc, IL-8, IL-1ß. We performed the same experiments with 17ß-estradiol (E2), the most abundant estrogen circulating in nonpregnant humans in order to compare these two different substances. We demonstrated the ability of 1â¯×â¯10-10â¯M NP to induce proliferation of LNCaP, S-phase progression, increase of ERα expression and its translocation from the cytoplasm to the nucleus. Moreover, we observed an up-regulation of key target genes involved in cell cycle and inflammation process. Particularly, after NP treatment, IL-8 and IL-1ß mRNA levels are increased more than 50% indicating a major NP involvement in inflammation processes than E2. These data suggest the proliferative effects of NP on prostate adenocarcinoma cells and highlight some aspects of molecular pathways involved in prostate responses to NP.