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BACKGROUND: Obesity-induced hypogonadism (OIH) is a prevalent, but often neglected condition in men, which aggravates the metabolic complications of overweight. While hypothalamic suppression of Kiss1-encoded kisspeptin has been suggested to contribute to OIH, the molecular mechanisms for such repression in obesity, and the therapeutic implications thereof, remain unknown. METHODS: A combination of bioinformatic, expression and functional analyses was implemented, assessing the role of the evolutionary-conserved miRNAs, miR-137 and miR-325, in mediating obesity-induced suppression of hypothalamic kisspeptin, as putative mechanism of central hypogonadism and metabolic comorbidities. The implications of such miR-137/325-kisspeptin interplay for therapeutic intervention in obesity were also explored using preclinical OIH models. RESULTS: MiR-137/325 repressed human KISS1 3'-UTR in-vitro and inhibited hypothalamic kisspeptin content in male rats, while miR-137/325 expression was up-regulated, and Kiss1/kisspeptin decreased, in the medio-basal hypothalamus of obese rats. Selective over-expression of miR-137 in Kiss1 neurons reduced Kiss1/ kisspeptin and partially replicated reproductive and metabolic alterations of OIH in lean mice. Conversely, interference of the repressive actions of miR-137/325 selectively on Kiss1 3'-UTR in vivo, using target-site blockers (TSB), enhanced kisspeptin content and reversed central hypogonadism in obese rats, together with improvement of glucose intolerance, insulin resistance and cardiovascular and inflammatory markers, despite persistent exposure to obesogenic diet. Reversal of OIH by TSB miR-137/325 was more effective than chronic kisspeptin or testosterone treatments in obese rats. CONCLUSIONS: Our data disclose that the miR-137/325-Kisspeptin repressive interaction is a major player in the pathogenesis of obesity-induced hypogonadism and a putative druggable target for improved management of this condition and its metabolic comorbidities in men suffering obesity. SIGNIFICANCE STATEMENT: Up to half of the men suffering obesity display also central hypogonadism, an often neglected complication of overweight that can aggravate the clinical course of obesity and its complications. The mechanisms for such obesity-induced hypogonadism remain poorly defined. We show here that the evolutionary conserved miR137/miR325 tandem centrally mediates obesity-induced hypogonadism via repression of the reproductive-stimulatory signal, kisspeptin; this may represent an amenable druggable target for improved management of hypogonadism and other metabolic complications of obesity.
Assuntos
Hipogonadismo , Hipotálamo , Kisspeptinas , MicroRNAs , Obesidade , MicroRNAs/genética , MicroRNAs/metabolismo , Hipogonadismo/genética , Hipogonadismo/metabolismo , Hipogonadismo/complicações , Kisspeptinas/genética , Kisspeptinas/metabolismo , Animais , Obesidade/metabolismo , Obesidade/complicações , Obesidade/genética , Masculino , Ratos , Hipotálamo/metabolismo , Humanos , Camundongos , Ratos Wistar , ComorbidadeRESUMO
Lysyl oxidase (LOX)-mediated extracellular matrix crosslinking modulates calcification in atherosclerosis and aortic valve disease; however, this enzyme also induces oxidative stress. We addressed the contribution of LOX-dependent oxidative stress to cardiovascular calcification. LOX is upregulated in human-calcified atherosclerotic lesions and atheromas from atherosclerosis-challenged LOX transgenic mice (TgLOXVSMC) and colocalized with a marker of oxidative stress (8-oxo-deoxyguanosine) in vascular smooth muscle cells (VSMCs). Similarly, in calcific aortic valves, high LOX expression was detected in valvular interstitial cells (VICs) positive for 8-oxo-deoxyguanosine, while LOX and LOXL2 expression correlated with osteogenic markers (SPP1 and RUNX2) and NOX2. In human VICs, mito-TEMPO and TEMPOL attenuated the increase in superoxide anion levels and the mineralization induced by osteogenic media (OM). Likewise, in OM-exposed VICs, ß-aminopropionitrile (a LOX inhibitor) ameliorated both oxidative stress and calcification. Gain- and loss-of-function approaches in VICs demonstrated that while LOX silencing negatively modulates oxidative stress and calcification induced by OM, lentiviral LOX overexpression exacerbated oxidative stress and VIC calcification, effects that were prevented by mito-TEMPO, TEMPOL, and ß-aminopropionitrile. Our data indicate that LOX-induced oxidative stress participates in the procalcifying effects of LOX activity in ectopic cardiovascular calcification, and highlight the multifaceted role played by LOX isoenzymes in cardiovascular diseases.
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During resolution of inflammation, specialized proresolving mediators (SPMs), including resolvins, are produced to restore tissue homeostasis. We hypothesized that there might be a dysregulation of SPMs pathways in pathological vascular remodeling and that resolvin D2 (RvD2) might prevent vascular remodeling and contractile and endothelial dysfunction in a model of obesity and hypertension. In aortic samples of patients with or without abdominal aortic aneurysms (AAA), we evaluated gene expression of enzymes involved in SPMs synthesis (ALOXs), SPMs receptors and pro-inflammatory genes. In an experimental model of aortic dilation induced by high fat diet (HFD, 60%, eighteen weeks) and angiotensin II (AngII) infusion (four weeks), we studied the effect of RvD2 administration in aorta and small mesenteric arteries structure and function and markers of inflammation. In human macrophages we evaluated the effects of AngII and RvD2 in macrophages function and SPMs profile. In patients, we found positive correlations between AAA and obesity, and between AAA and expression of ALOX15, RvD2 receptor GPR18, and pro-inflammatory genes. There was an inverse correlation between the expression of aortic ALOX15 and AAA growth rate. In the mice model, RvD2 partially prevented the HFD plus AngII-induced obesity and adipose tissue inflammation, hypertension, aortic and mesenteric arteries remodeling, hypercontratility and endothelial dysfunction, and the expression of vascular proinflammatory markers and cell apoptosis. In human macrophages, RvD2 prevented AngII-induced impaired efferocytosis and switched SPMs profile. RvD2 might represent a novel protective strategy in preventing vascular damage associated to hypertension and obesity likely through effects in vascular and immune cells.
Assuntos
Ácidos Docosa-Hexaenoicos , Hipertensão , Camundongos Endogâmicos C57BL , Obesidade , Remodelação Vascular , Animais , Masculino , Humanos , Ácidos Docosa-Hexaenoicos/farmacologia , Hipertensão/metabolismo , Hipertensão/tratamento farmacológico , Obesidade/complicações , Obesidade/metabolismo , Remodelação Vascular/efeitos dos fármacos , Camundongos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Dieta Hiperlipídica/efeitos adversos , Angiotensina II , Aneurisma da Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Camundongos Obesos , Vasoconstrição/efeitos dos fármacos , Inflamação/patologia , Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Modelos Animais de DoençasRESUMO
The angiotensin (Ang)-(1-12)/Ang II pathway contributes to cardiac pathology. However, its involvement in the development of peripheral endothelial dysfunction associated with heart failure (HF) remains unknown. Therefore, this study aimed to characterise the effect of exogenous Ang-(1-12) and its conversion to Ang II on endothelial function using the murine model of HF (Tgαq*44 mice), focusing on the role of chymase and vascular-derived thromboxane A2 (TXA2). Ex vivo myographic assessments of isolated aorta showed impaired endothelium-dependent vasodilation in late-stage HF in 12-month-old Tgαq*44 mice. However, endothelium-dependent vasodilation was fully preserved in the early stage of HF in 4-month-old Tgαq*44 mice and 4- and 12-month-old FVB control mice. Ang-(1-12) impaired endothelium-dependent vasodilation in 4- and 12-month-old Tgαq*44 mice, that was associated with increased Ang II production. The chymase inhibitor chymostatin did not inhibit this response. Interestingly, TXA2 production reflected by TXB2 measurement was upregulated in response to Ang-(1-12) and Ang II in aortic rings isolated from 12-month-old Tgαq*44 mice but not from 4-month-old Tgαq*44 mice or age-matched FVB mice. Furthermore, in vivo magnetic resonance imaging showed that Ang-(1-12) impaired endothelium-dependent vasodilation in the aorta of Tgαq*44 mice and FVB mice. However, this response was inhibited by angiotensin I converting enzyme (ACE) inhibitor; perindopril, angiotensin II receptor type 1 (AT1) antagonist; losartan and TXA2 receptor (TP) antagonist-picotamide in 12-month-old-Tgαq*44 mice only. In conclusion, the chymase-independent vascular Ang-(1-12)/Ang II pathway and subsequent TXA2 overactivity contribute to systemic endothelial dysfunction in the late stage of HF in Tgαq*44 mice. Therefore, the vascular TXA2 receptor represents a pharmacotherapeutic target to improve peripheral endothelial dysfunction in chronic HF.
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Insuficiência Cardíaca , Doenças Vasculares , Animais , Camundongos , Angiotensina I , Angiotensina II/metabolismo , Inibidores da Enzima Conversora de Angiotensina , Quimases , Modelos Animais de Doenças , Insuficiência Cardíaca/metabolismo , Camundongos EndogâmicosRESUMO
Immune cells have an important role in the tumor-microenvironment. Macrophages may tune the immune response toward inflammatory or tolerance pathways. Tumor-associated macrophages (TAM) have a string of immunosuppressive functions and they are considered a therapeutic target in cancer. This study aimed to analyze the effects of trabectedin, an antitumor agent, on the tumor-microenvironment through the characterization of the electrophysiological and molecular phenotype of macrophages. Experiments were performed using the whole-cell configuration of the patch-clamp technique in resident peritoneal mouse macrophages. Trabectedin does not directly interact with KV1.5 and KV1.3 channels, but their treatment (16 h) with sub-cytotoxic concentrations of trabectedin increased their KV current due to an upregulation of KV1.3 channels. In vitro generated TAM (TAMiv) exhibited an M2-like phenotype. TAMiv generated a small KV current and express high levels of M2 markers. K+ current from TAMs isolated from tumors generated in mice is a mixture of KV and KCa, and in TAM isolated from tumors generated in trabectedin-treated mice, the current is mostly driven by KCa. We conclude that the antitumor capacity of trabectedin is not only due to its effects on tumor cells, but also to the modulation of the tumor microenvironment, due, at least in part, to the modulation of the expression of different macrophage ion channels.
Assuntos
Macrófagos , Microambiente Tumoral , Camundongos , Animais , Trabectedina/farmacologia , Macrófagos/metabolismo , Ativação de Macrófagos , Fenômenos EletrofisiológicosRESUMO
BACKGROUND: Resolution of inflammation is orchestrated by specialized proresolving lipid mediators (SPMs), and this would be impaired in some cardiovascular diseases. Among SPMs, resolvins (Rv) have beneficial effects in cardiovascular pathologies, but little is known about their effect on cardiovascular damage in hypertension. METHODS: Aorta, small mesenteric arteries, heart, and peritoneal macrophages were taken from C57BL/6J mice, infused or not with angiotensin II (AngII; 1.44 mg/kg/day, 14 days) in presence or absence of resolvin D2 (RvD2) (100 ng/mice, every second day) starting 1 day before or 7 days after AngII infusion. RESULTS: Enzymes and receptors involved in SPMs biosynthesis and signaling were increased in aorta or heart from AngII-infused mice. We also observed a differential regulation of SPMs in heart from these mice. Preventive treatment with RvD2 partially avoided AngII-induced hypertension and protected the heart and large and small vessels against functional and structural alterations induced by AngII. RvD2 increased the availability of vasoprotective factors, modified SPMs profile, decreased cardiovascular fibrosis, and increased the infiltration of pro-resolving macrophages. When administered in hypertensive animals with established cardiovascular damage, RvD2 partially improved cardiovascular function and structure, decreased fibrosis, reduced the infiltration of neutrophils, and shifted macrophage phenotype toward a pro-resolving phenotype. CONCLUSIONS: There is a disbalance between proinflammatory and resolution mediators in hypertension. RvD2 protects cardiovascular function and structure when administered before and after the development of hypertension by modulating vascular factors, fibrosis and inflammation. Activating resolution mechanisms by treatment with RvD2 may represent a novel therapeutic strategy for the treatment of hypertensive cardiovascular disease.
Assuntos
Angiotensina II , Hipertensão , Camundongos , Animais , Camundongos Endogâmicos C57BL , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , FibroseRESUMO
La hipertensión y la obesidad son importantes problemas de salud en todo el mundo con notables consecuencias sobre la morbilidad y la mortalidad. De hecho, tanto la hipertensión como la obesidad son importantes factores de riesgo para el desarrollo de enfermedades cardiovasculares. La disfunción endotelial, el remodelado vascular y las alteraciones en la mecánica vascular son aspectos comunes del daño vascular en la hipertensión, la obesidad y los aneurismas. Durante las últimas décadas, se ha demostrado la importancia de la inflamación de bajo grado en el daño vascular asociado a las enfermedades cardiovasculares. Dicha inflamación se caracteriza por la acumulación de células inflamatorias en la vasculatura, así como por el aumento de citoquinas proinflamatorias locales y circulantes. Por tanto, la identificación de nuevos mediadores inflamatorios implicados en dicho daño se ha convertido en un área de investigación muy importante.El interferón-γ (IFNγ) o el factor de necrosis tumoral-α (TNFα) son importantes citoquinas implicadas en el daño vascular asociado a la hipertensión. Además, se acepta que el TNFα es un mediador clave implicado en la resistencia a la insulina y el daño vascular observado en la obesidad. Ambas citoquinas inducen la expresión del gen 15 estimulado por interferón (ISG15), una proteína similar a la ubiquitina que induce una modificación postraducional reversible (ISGilación) y que también puede secretarse como forma libre. Las funciones de ISG15 están principalmente relacionadas con la respuesta inmune frente a infecciones, sin embargo, podría ser también una interesante nueva diana del daño cardiovascular. (AU)
Hypertension and obesity are major health problems worldwide with significant consequences on morbidity and mortality. In fact, both hypertension and obesity are important risk factors for the development of cardiovascular diseases. Endothelial dysfunction, vascular remodeling, and alterations in vascular mechanics are common aspects of vascular damage in hypertension, obesity, and aneurysms. During the last decades, the importance of low-grade inflammation in vascular damage associated with cardiovascular diseases has been demonstrated. This inflammation is characterized by the accumulation of inflammatory cells in the vasculature, as well as by the increase of local and circulating pro-inflammatory cytokines. Therefore, the identification of new inflammatory mediators involved in this damage has become a very important area of research.Interferón-γ (IFNγ) or tumor necrosis tumoral-α (TNFα) are important cytokines involved in the vascular damage associated with hypertension. Furthermore, it is accepted that TNFα is a key mediator involved in insulin resistance and vascular damage observed in obesity. Both cytokines induce the expression of interferon-stimulated gene 15 (ISG15), a protein similar to ubiquitin that induces a reversible post-translational modification (ISGylation) and that can also be secreted as a free form. The functions of ISG15 are mainly related to the immune response against infections, however, it could also be an interesting new target for cardiovascular damage. (AU)
Assuntos
Humanos , Hipertensão , Obesidade , Estresse Oxidativo , Inflamação , Doenças Cardiovasculares , MortalidadeRESUMO
Carob, the fruit of Ceratonia siliqua L. exerts antidiabetic, anti-inflammatory, and antioxidant effects and could be a useful strategy for the treatment and/or prevention of metabolic syndrome (MetS). The aim of this study was to analyze whether supplementation with a carob fruit extract (CSAT+®), alone or in combination with aerobic training, accelerates the recovery of cardiometabolic health in mice with MetS subjected to a caloric restriction. For this purpose, mice were fed with a high fat (58% kcal from fat)/high sugar diet for 23 weeks to induce MetS. During the next two weeks, mice with MetS were switched to a diet with a lower caloric content (25% kcal from fat) supplemented or not with CSAT+® (4.8%) and/or subjected to aerobic training. Both caloric reduction and aerobic training improved the lipid profile and attenuated MetS-induced insulin resistance measured as HOMA-IR. However, only supplementation with CSAT+® enhanced body weight loss, increased the circulating levels of adiponectin, and lowered the plasma levels of IL-6. Moreover, CSAT+® supplementation was the only effective strategy to reduce the weight of epidydimal adipose tissue and to improve insulin sensitivity in the liver and in skeletal muscle. Although all interventions improved endothelial function in aorta segments, only supplementation with CSAT+® reduced obesity-induced hypertension, prevented endothelial dysfunction in mesenteric arteries, and decreased the vascular response of aorta segments to the vasoconstrictor AngII. The beneficial cardiometabolic effects of CSAT+® supplementation, alone or in combination with aerobic training, were associated with decreased mRNA levels of pro-inflammatory markers such as MCP-1, TNFα, IL-1ß, and IL-6 and with increased gene expression of antioxidant enzymes, such as GSR, GPX-3, and SOD-1 in the liver, gastrocnemius, retroperitoneal adipose tissue, and aorta. In conclusion, supplementation with CSAT+®, alone or in combination with aerobic training, to mice with MetS subjected to caloric restriction for two weeks enhances body weight loss, improves the lipid profile and insulin sensitivity, and exerts antihypertensive effects through its anti-inflammatory and antioxidant properties.
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In recent years, gut dysbiosis has been related to some peripheral vascular alterations linked to hypertension. In this work, we explore whether gut dysbiosis is related to vascular innervation dysfunction and altered nitric oxide (NO) production in the superior mesenteric artery, one of the main vascular beds involved in peripheral vascular resistance. For this purpose, we used spontaneously hypertensive rats, either treated or not with the commercial synbiotic formulation Prodefen® (108 colony forming units/day, 4 weeks). Prodefen® diminished systolic blood pressure and serum endotoxin, as well as the vasoconstriction elicited by electrical field stimulation (EFS), and enhanced acetic and butyric acid in fecal samples, and the vasodilation induced by the exogenous NO donor DEA-NO. Unspecific nitric oxide synthase (NOS) inhibitor L-NAME increased EFS-induced vasoconstriction more markedly in rats supplemented with Prodefen®. Both neuronal NO release and neuronal NOS activity were enhanced by Prodefen®, through a hyperactivation of protein kinase (PK)A, PKC and phosphatidylinositol 3 kinase-AKT signaling pathways. The superoxide anion scavenger tempol increased both NO release and DEA-NO vasodilation only in control animals. Prodefen® caused an increase in both nuclear erythroid related factor 2 and superoxide dismutase activities, consequently reducing both superoxide anion and peroxynitrite releases. In summary, Prodefen® could be an interesting non-pharmacological approach to ameliorate hypertension.
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Vascular remodeling is a typical feature of vascular diseases, such as atherosclerosis, aneurysms or restenosis. Excessive inflammation is a key mechanism underlying vascular remodeling via the modulation of vascular fibrosis, phenotype and function. Recent evidence suggests that not only augmented inflammation but unresolved inflammation might also contribute to different aspects of vascular diseases. Resolution of inflammation is mediated by a family of specialized pro-resolving mediators (SPMs) that limit immune cell infiltration and initiate tissue repair mechanisms. SPMs (lipoxins, resolvins, protectins, maresins) are generated from essential polyunsaturated fatty acids. Synthases and receptors for SPMs were initially described in immune cells, but they are also present in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs), where they regulate processes important for vascular physiology, such as EC activation and VSMC phenotype. Evidence from genetic models targeting SPM pathways and pharmacological supplementation with SPMs have demonstrated that these mediators may play a protective role against the development of vascular remodeling in atherosclerosis, aneurysms and restenosis. This review focuses on the latest advances in understanding the role of SPMs in vascular cells and their therapeutic effects in the vascular remodeling associated with different cardiovascular diseases.
Assuntos
Aterosclerose , Mediadores da Inflamação , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Eicosanoides/farmacologia , Células Endoteliais/metabolismo , Humanos , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Remodelação VascularRESUMO
La hipertensión y la obesidad son importantes problemas de salud en todo el mundo con notables consecuencias sobre la morbilidad y la mortalidad. De hecho, tanto la hipertensión como la obesidad son importantes factores de riesgo para el desarrollo de enfermedades cardiovasculares. La disfunción endotelial, el remodelado vascular y las alteraciones en la mecánica vascular son aspectos comunes del daño vascular en la hipertensión, la obesidad y los aneurismas. Durante las últimas décadas, se ha demostrado la importancia de la inflamación de bajo grado en el daño vascular asociado a las enfermedades cardiovasculares. Dicha inflamación se caracteriza por la acumulación de células inflamatorias en la vasculatura, así como por el aumento de citoquinas proinflamatorias locales y circulantes. Por tanto, la identificación de nuevos mediadores inflamatorios implicados en dicho daño se ha convertido en un área de investigación muy importante. El interferón-γ (IFNγ) o el factor de necrosis tumoral-α (TNFα) son importantes citoquinas implicadas en el daño vascular asociado a la hipertensión. Además, se acepta que el TNFα es un mediador clave implicado en la resistencia a la insulina y el daño vascular observado en la obesidad. Ambas citoquinas inducen la expresión del gen 15 estimulado por interferón (ISG15), una proteína similar a la ubiquitina que induce una modificación postraducional reversible (ISGilación) y que también puede secretarse como forma libre. Las funciones de ISG15 están principalmente relacionadas con la respuesta inmune frente a infecciones, sin embargo, podría ser también una interesante nueva diana del daño cardiovascular.(AU)
Hypertension and obesity are major health problems worldwide with significant consequences on morbidity and mortality. In fact, both hypertension and obesity are important risk factors for the development of cardiovascular diseases. Endothelial dysfunction, vascular remodeling, and alterations in vascular mechanics are common aspects of vascular damage in hypertension, obesity, and aneurysms. During the last decades, the importance of low-grade inflammation in vascular damage associated with cardiovascular diseases has been demonstrated. This inflammation is characterized by the accumulation of inflammatory cells in the vasculature, as well as by the increase of local and circulating pro-inflammatory cytokines. Therefore, the identification of new inflammatory mediators involved in this damage has become a very important area of research. Interferón-γ (IFNγ) or tumor necrosis tumoral-α (TNFα) are important cytokines involved in the vascular damage associated with hypertension. Furthermore, it is accepted that TNFα is a key mediator involved in insulin resistance and vascular damage observed in obesity. Both cytokines induce the expression of interferon-stimulated gene 15 (ISG15), a protein similar to ubiquitin that induces a reversible post-translational modification (ISGylation) and that can also be secreted as a free form. The functions of ISG15 are mainly related to the immune response against infections, however, it could also be an interesting new target for cardiovascular damage.(AU)
Assuntos
Humanos , Hipertensão , Obesidade , Interferon gama , Fator de Necrose Tumoral alfa , Aneurisma da Aorta Abdominal , Resistência à Insulina , Estresse OxidativoRESUMO
AIMS: Interferon-stimulated gene 15 (ISG15) encodes a ubiquitin-like protein that induces a reversible post-translational modification (ISGylation) and can also be secreted as a free form. ISG15 plays an essential role as host-defence response to microbial infection; however, its contribution to vascular damage associated with hypertension is unknown. METHODS AND RESULTS: Bioinformatics identified ISG15 as a mediator of hypertension-associated vascular damage. ISG15 expression positively correlated with systolic and diastolic blood pressure and carotid intima-media thickness in human peripheral blood mononuclear cells. Consistently, Isg15 expression was enhanced in aorta from hypertension models and in angiotensin II (AngII)-treated vascular cells and macrophages. Proteomics revealed differential expression of proteins implicated in cardiovascular function, extracellular matrix and remodelling, and vascular redox state in aorta from AngII-infused ISG15-/- mice. Moreover, ISG15-/- mice were protected against AngII-induced hypertension, vascular stiffness, elastin remodelling, endothelial dysfunction, and expression of inflammatory and oxidative stress markers. Conversely, mice with excessive ISGylation (USP18C61A) show enhanced AngII-induced hypertension, vascular fibrosis, inflammation and reactive oxygen species (ROS) generation along with elastin breaks, aortic dilation, and rupture. Accordingly, human and murine abdominal aortic aneurysms showed augmented ISG15 expression. Mechanistically, ISG15 induces vascular ROS production, while antioxidant treatment prevented ISG15-induced endothelial dysfunction and vascular remodelling. CONCLUSION: ISG15 is a novel mediator of vascular damage in hypertension through oxidative stress and inflammation.
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Aneurisma da Aorta Abdominal , Hipertensão , Camundongos , Humanos , Animais , Elastina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Angiotensina II/metabolismo , Interferons/metabolismo , Leucócitos Mononucleares/metabolismo , Espessura Intima-Media Carotídea , Estresse Oxidativo , Hipertensão/induzido quimicamente , Hipertensão/genética , Hipertensão/metabolismo , Oxirredução , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/prevenção & controle , Inflamação , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND AND PURPOSE: KV 1.3 channels are expressed in vascular smooth muscle cells (VSMCs), where they contribute to proliferation rather than contraction and participate in vascular remodelling. KV 1.3 channels are also expressed in macrophages, where they assemble with KV 1.5 channels (KV 1.3/KV 1.5), whose activation generates a KV current. In macrophages, the KV 1.3/KV 1.5 ratio is increased by classical activation (M1). Whether these channels are involved in angiotensin II (AngII)-induced vascular remodelling, and whether they can modulate the macrophage phenotype in hypertension, remains unknown. We characterized the role of KV 1.3 channels in vascular damage in hypertension. EXPERIMENTAL APPROACH: We used AngII-infused mice treated with two selective KV 1.3 channel inhibitors (HsTX[R14A] and [EWSS]ShK). Vascular function and structure were measured using wire and pressure myography, respectively. VSMC and macrophage electrophysiology were studied using the patch-clamp technique; gene expression was analysed using RT-PCR. KEY RESULTS: AngII increased KV 1.3 channel expression in mice aorta and peritoneal macrophages which was abolished by HsTX[R14A] treatment. KV 1.3 inhibition did not prevent hypertension, vascular remodelling, or stiffness but corrected AngII-induced macrophage infiltration and endothelial dysfunction in the small mesenteric arteries and/or aorta, via a mechanism independent of electrophysiological changes in VSMCs. AngII modified the electrophysiological properties of peritoneal macrophages, indicating an M1-like activated state, with enhanced expression of proinflammatory cytokines that induced endothelial dysfunction. These effects were prevented by KV 1.3 blockade. CONCLUSIONS AND IMPLICATIONS: We unravelled a new role for KV 1.3 channels in the macrophage-dependent endothelial dysfunction induced by AngII in mice which might be due to modulation of macrophage phenotype.
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Angiotensina II , Hipertensão , Angiotensina II/toxicidade , Animais , Hipertensão/induzido quimicamente , Macrófagos , Camundongos , Miócitos de Músculo Liso , Remodelação VascularRESUMO
We aimed to determine whether an experimental model of hyperthyroidism could alter the function of sympathetic and nitrergic components of mesenteric innervation. For this purpose, male Wistar rats were divided into (1) control rats (CT) and (2) rats infused with L-Thyroxine (HT). Body weight gain and adipose tissue accumulation were lower in HT rats, while systolic blood pressure and citrate synthase activity in the soleus muscle were increased by HT. In segments from the superior mesenteric artery, the application of an electrical field stimulation (EFS) induced a vasoconstrictor response, which was lower in arteries from HT animals. The alpha-adrenoceptor antagonist phentolamine diminished EFS-induced vasoconstriction to a lower extent in HT arteries, while the purinergic receptor antagonist suramin reduced contractile response to EFS only in segments from CT. In line with this, noradrenaline release, tyrosine hydroxylase expression and activation and dopamine ß hydroxylase expression were diminished in HT. The unspecific nitric oxide synthase (NOS) inhibitor L-NAME increased EFS-induced vasoconstriction more markedly in segments from HT rats. NO release was enhanced in HT, probably due to an enhancement in neuronal NOS activity, in which a hyperactivation of both PKC and PI3K-AKT signaling pathways might play a relevant role. In conclusion, perivascular mesenteric innervation might contribute to reduce the vascular resistance observed in hyperthyroidism.
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Peso Corporal/efeitos dos fármacos , Hipertireoidismo/genética , Óxido Nítrico Sintase/genética , Óxido Nítrico/genética , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/crescimento & desenvolvimento , Animais , Peso Corporal/genética , Modelos Animais de Doenças , Estimulação Elétrica , Humanos , Hipertireoidismo/metabolismo , Hipertireoidismo/patologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/crescimento & desenvolvimento , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/crescimento & desenvolvimento , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Ratos , Ratos Wistar , Tiroxina/farmacologia , Vasoconstrição/genéticaRESUMO
The acute-on-chronic liver failure (ACLF) is a syndrome characterized by liver decompensation, hepatic encephalopathy (HE) and high mortality. We aimed to determine the mechanisms implicated in the development of HE-associated cerebral vasculopathy in a microsurgical liver cholestasis (MHC) model of ACLF. Microsurgical liver cholestasis was induced by ligating and extracting the common bile duct and four bile ducts. Sham-operated and MHC rats were maintained for eight postoperative weeks Bradykinin-induced vasodilation was greater in middle cerebral arteries from MHC rats. Both Nω-Nitro-L-arginine methyl ester and indomethacin diminished bradykinin-induced vasodilation largely in arteries from MHC rats. Nitrite and prostaglandin (PG) F1α releases were increased, whereas thromboxane (TX) B2 was not modified in arteries from MHC. Expressions of endothelial nitric oxide synthase (eNOS), inducible NOS, and cyclooxygenase (COX) 2 were augmented, and neuronal NOS (nNOS), COX-1, PGI2 synthase, and TXA2S were unmodified. Phosphorylation was augmented for eNOS and unmodified for nNOS. Altogether, these endothelial alterations might collaborate to increase brain blood flow in HE.
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An important link exists between hypertension and inflammation. Hypertensive patients present elevated circulating levels of proinflammatory cytokines, including interleukin-17A (IL-17A). This cytokine participates in host defense, autoimmune and chronic inflammatory pathologies, and cardiovascular diseases, mainly through the regulation of proinflammatory factors. Emerging evidence also suggests that IL-17A could play a role in regulating blood pressure and end-organ damage. Here, our preclinical studies in a murine model of systemic IL-17A administration showed that increased levels of circulating IL-17A raised blood pressure induced inward remodeling of small mesenteric arteries (SMAs) and arterial stiffness. In IL-17A-infused mice, treatment with hydralazine and hydrochlorothiazide diminished blood pressure elevation, without modifying mechanical and structural properties of SMA, suggesting a direct vascular effect of IL-17A. The mechanisms of IL-17A seem to involve an induction of vascular smooth muscle cell (VSMC) hypertrophy and phenotype changes, in the absence of extracellular matrix (ECM) proteins accumulation. Accordingly, treatment with an IL-17A neutralizing antibody diminished SMA remodeling in a model of angiotensin II (Ang II) infusion. Moreover, in vitro studies in VSMCs reported here, provide further evidence of the direct effects of IL-17A on cell growth responses. Our experimental data suggest that IL-17A is a key mediator of vascular remodeling of the small arteries, which might contribute, at least in part, to blood pressure elevation.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Interleucina-17/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Angiotensina II/administração & dosagem , Angiotensina II/farmacologia , Animais , Forma Celular/efeitos dos fármacos , Humanos , Hipertensão/fisiopatologia , Interleucina-17/administração & dosagem , Masculino , Artérias Mesentéricas/fisiologia , Camundongos Endogâmicos C57BL , Músculo Liso Vascular , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Vasoconstritores/administração & dosagem , Vasoconstritores/farmacologiaRESUMO
Hypertension is now considered as an inflammatory disease, and the kidney is a key end-organ target. Experimental and clinical studies suggest that interleukin 17A (IL-17A) is a promising therapeutic target in immune and chronic inflammatory diseases, including hypertension and kidney disease. Elevated circulating IL-17A levels have been observed in hypertensive patients. Our aim was to investigate whether chronically elevated circulating IL-17A levels could contribute to kidney damage, using a murine model of systemic IL-17A administration. Blood pressure increased after 14 days of IL-17A infusion in mice when compared with that in control mice, and this was associated to kidney infiltration by inflammatory cells, including CD3+ and CD4+ lymphocytes and neutrophils. Moreover, proinflammatory factors and inflammatory-related intracellular mechanisms were upregulated in kidneys from IL-17A-infused mice. In line with these findings, in the model of angiotensin II infusion in mice, IL-17A blockade, using an anti-IL17A neutralizing antibody, reduced kidney inflammatory cell infiltrates and chemokine overexpression. In kidney biopsies from patients with hypertensive nephrosclerosis, IL-17A positive cells, mainly Th17 and γδ T lymphocytes, were found. Overall, the results support a pathogenic role of IL-17A in hypertensive kidney disease-associated inflammation. Therapeutic approaches targeting this cytokine should be explored to prevent hypertension-induced kidney injury.
RESUMO
Organ regeneration is preceded by the recruitment of innate immune cells, which play an active role during repair and regrowth. Here, we studied macrophage subtypes during organ regeneration in the zebrafish, an animal model with a high regenerative capacity. We identified a macrophage subpopulation expressing Wilms tumor 1b (wt1b), which accumulates within regenerating tissues. This wt1b+ macrophage population exhibited an overall pro-regenerative gene expression profile and different migratory behavior compared to the remainder of the macrophages. Functional studies showed that wt1b regulates macrophage migration and retention at the injury area. Furthermore, wt1b-null mutant zebrafish presented signs of impaired macrophage differentiation, delayed fin growth upon caudal fin amputation, and reduced cardiomyocyte proliferation following cardiac injury that correlated with altered macrophage recruitment to the regenerating areas. We describe a pro-regenerative macrophage subtype in the zebrafish and a role for wt1b in organ regeneration.
Assuntos
Nadadeiras de Animais/fisiologia , Coração/fisiologia , Macrófagos/metabolismo , Regeneração , Proteínas WT1/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Macrófagos/citologia , Proteínas WT1/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genéticaRESUMO
The nuclear receptor NOR-1 (Neuron-derived Orphan Receptor-1) has recently been involved in vascular remodeling and coronary artery disease, however, to date, only a few NOR-1 target genes have been described. We aimed to identify genes regulated by NOR-1 in human vascular smooth muscle cells (VSMC). Lentiviral overexpression of NOR-1 increases reactive oxygen species (ROS) in human VSMC. In accordance, NOR-1 strongly increased NADPH oxidase NOX1 mRNA and protein levels, while NOR-1 silencing significantly reduced NOX1 expression. Luciferase reporter, site-directed mutagenesis and EMSA studies identified two nerve growth factor-induced clone B (NGFI-B)-response elements (NBREs) in NOX1 promoter as essential elements for NOR-1 responsiveness. NOR-1 and NOX1 were co-expressed by VSMC in human atherosclerotic lesions, and NOX1 knockdown counteracted the increased ROS production and cell migration induced by NOR-1 overexpression. NOR-1 also modulated the expression of other enzymes involved in cellular redox status, in particular, upregulated superoxide dismutase-1 (SOD1) and SOD3 while downregulated SOD2 and NOX4. NOR-1 induced SOD1 and SOD3 transcriptional activity and participated in the modulation of SOD3 by inflammatory stimuli. By contrast, NOR-1 impaired SOD2 transcription antagonizing NFκB signaling. These results indicate that NOR-1 induces NOX1 in human VSMC and participates in the complex gene networks regulating oxidative stress and redox homeostasis in the vasculature.
Assuntos
Homeostase/fisiologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Oxirredução , Análise de Variância , Movimento Celular/fisiologia , Células Cultivadas , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Redes Reguladoras de Genes , Homeostase/genética , Humanos , Isoenzimas/metabolismo , NADPH Oxidase 1/genética , NADPH Oxidase 1/metabolismo , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Estatísticas não Paramétricas , Superóxido Dismutase/metabolismo , Ativação TranscricionalRESUMO
mPGES-1 (microsomal prostaglandin E synthase-1), the downstream enzyme responsible for PGE2 (prostaglandin E2) synthesis in inflammatory conditions and oxidative stress are increased in vessels from hypertensive animals. We evaluated the role of mPGES-1-derived PGE2 in the vascular dysfunction and remodeling in hypertension and the possible contribution of oxidative stress. We used human peripheral blood mononuclear cells from asymptomatic patients, arteries from untreated and Ang II (angiotensin II)-infused mPGES-1-/- and mPGES-1+/+ mice, and vascular smooth muscle cells exposed to PGE2 In human cells, we found a positive correlation between mPGES-1 mRNA and carotid intima-media thickness (r=0.637; P<0.001) and with NADPH oxidase-dependent superoxide production (r=0.417; P<0.001). In Ang II-infused mice, mPGES-1 deletion prevented all of the following: (1) the augmented wall:lumen ratio, vascular stiffness, and altered elastin structure; (2) the increased gene expression of profibrotic and proinflammatory markers; (3) the increased vasoconstrictor responses and endothelial dysfunction; (4) the increased NADPH oxidase activity and the diminished mitochondrial membrane potential; and (5) the increased reactive oxygen species generation and reduced NO bioavailability. In vascular smooth muscle cells or aortic segments, PGE2 increased NADPH oxidase expression and activity and reduced mitochondrial membrane potential, effects that were abolished by antagonists of the PGE2 receptors (EP), EP1 and EP3, and by JNK (c-Jun N-terminal kinase) and ERK1/2 (extracellular-signal-regulated kinases 1/2) inhibition. Deletion of mPGES-1 augmented vascular production of PGI2 suggesting rediversion of the accumulated PGH2 substrate. In conclusion, mPGES-1-derived PGE2 is involved in vascular remodeling, stiffness, and endothelial dysfunction in hypertension likely through an increase of oxidative stress produced by NADPH oxidase and mitochondria.