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1.
Nat Med ; 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606551

RESUMO

The pathophysiology and trajectory of post-Coronavirus Disease 2019 (COVID-19) syndrome is uncertain. To clarify multisystem involvement, we undertook a prospective cohort study including patients who had been hospitalized with COVID-19 (ClinicalTrials.gov ID NCT04403607 ). Serial blood biomarkers, digital electrocardiography and patient-reported outcome measures were obtained in-hospital and at 28-60 days post-discharge when multisystem imaging using chest computed tomography with pulmonary and coronary angiography and cardio-renal magnetic resonance imaging was also obtained. Longer-term clinical outcomes were assessed using electronic health records. Compared to controls (n = 29), at 28-60 days post-discharge, people with COVID-19 (n = 159; mean age, 55 years; 43% female) had persisting evidence of cardio-renal involvement and hemostasis pathway activation. The adjudicated likelihood of myocarditis was 'very likely' in 21 (13%) patients, 'probable' in 65 (41%) patients, 'unlikely' in 56 (35%) patients and 'not present' in 17 (11%) patients. At 28-60 days post-discharge, COVID-19 was associated with worse health-related quality of life (EQ-5D-5L score 0.77 (0.23) versus 0.87 (0.20)), anxiety and depression (PHQ-4 total score 3.59 (3.71) versus 1.28 (2.67)) and aerobic exercise capacity reflected by predicted maximal oxygen utilization (20.0 (7.6) versus 29.5 (8.0) ml/kg/min) (all P < 0.01). During follow-up (mean, 450 days), 24 (15%) patients and two (7%) controls died or were rehospitalized, and 108 (68%) patients and seven (26%) controls received outpatient secondary care (P = 0.017). The illness trajectory of patients after hospitalization with COVID-19 includes persisting multisystem abnormalities and health impairments that could lead to substantial demand on healthcare services in the future.

2.
Eur Heart J ; 43(19): 1832-1845, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35567552

RESUMO

AIMS: Hypogonadism is associated with cardiovascular disease. However, the cardiovascular impact of hypogonadism during development is unknown. Using hypospadias as a surrogate of hypogonadism, we investigated whether hypospadias is associated with vascular dysfunction and is a risk factor for cardiovascular disease. METHODS AND RESULTS: Our human study spanned molecular mechanistic to epidemiological investigations. Clinical vascular phenotyping was performed in adolescents with hypospadias and controls. Small subcutaneous arteries from penile skin from boys undergoing hypospadias repair and controls were isolated and functional studies were assessed by myography. Vascular smooth muscle cells were used to assess: Rho kinase, reactive oxygen species (ROS), nitric oxide synthase/nitric oxide, and DNA damage. Systemic oxidative stress was assessed in plasma and urine. Hospital episode data compared men with a history of hypospadias vs. controls. In adolescents with hypospadias, systolic blood pressure (P = 0.005), pulse pressure (P = 0.03), and carotid intima-media thickness standard deviation scores (P = 0.01) were increased. Arteries from boys with hypospadias demonstrated increased U46619-induced vasoconstriction (P = 0.009) and reduced acetylcholine-induced endothelium-dependent (P < 0.0001) and sodium nitroprusside-induced endothelium-independent vasorelaxation (P < 0.0001). Men born with hypospadias were at increased risk of arrhythmia [odds ratio (OR) 2.8, 95% confidence interval (CI) 1.4-5.6, P = 0.003]; hypertension (OR 4.2, 95% CI 1.5-11.9, P = 0.04); and heart failure (OR 1.9, 95% CI 1.7-114.3, P = 0.02). CONCLUSION: Hypospadias is associated with vascular dysfunction and predisposes to hypertension and cardiovascular disease in adulthood. Underlying mechanisms involve perturbed Rho kinase- and Nox5/ROS-dependent signalling. Our novel findings delineate molecular mechanisms of vascular injury in hypogonadism, and identify hypospadias as a cardiovascular risk factor in males.


Assuntos
Doenças Cardiovasculares , Fatores de Risco de Doenças Cardíacas , Hipertensão , Hipogonadismo , Hipospadia , Adolescente , Doenças Cardiovasculares/complicações , Espessura Intima-Media Carotídea , Endotélio Vascular , Humanos , Hipertensão/complicações , Hipogonadismo/complicações , Hipospadia/complicações , Masculino , Óxido Nítrico , Espécies Reativas de Oxigênio , Fatores de Risco , Vasodilatação , Quinases Associadas a rho
3.
Clin Sci (Lond) ; 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35441670

RESUMO

Vascular endothelial growth factor antagonism with angiogenesis inhibitors in cancer patients induces a "preeclampsia-like" syndrome including hypertension, proteinuria and elevated endothelin (ET)-1. Cyclo-oxygenase (COX) inhibition with aspirin is known to prevent the onset of preeclampsia in high-risk patients. In the present study we hypothesised that treatment with aspirin would prevent the development of angiogenesis inhibitor-induced hypertension and kidney damage. Our aims were to compare the effects of low-dose (COX-1 inhibition) and high-dose (dual COX-1 and COX-2 inhibition) aspirin on blood pressure, vascular function, oxidative stress, ET-1 and prostanoid levels and kidney damage during angiogenesis inhibitor therapy in rodents. To this end, Wistar Kyoto rats were treated with vehicle, angiogenesis inhibitor (sunitinib) alone or in combination with low-dose or high-dose aspirin for 8 days (n=5-7/group). Our results demonstrate that prostacyclin (PGI2) and ET-1 are increased during angiogenesis inhibitor therapy, while thromboxane (TXA2) was unchanged. Both low-dose and high-dose aspirin blunted angiogenesis inhibitor-induced hypertension and vascular superoxide production to a similar extent, whereas only high-dose aspirin prevented albuminuria. While circulating TXA2 and prostaglandin F2α levels were reduced by both low-dose and high-dose aspirin, circulating and urinary levels PGI2 were only reduced by high-dose aspirin. Lastly, treatment with aspirin did not significantly affect ET-1 or vascular function. Collectively our findings suggest that prostanoids contribute to the development of angiogenesis inhibitor-induced hypertension and renal damage and that targeting the prostanoid pathway could be an effective strategy to mitigate the unwanted cardiovascular and renal toxicities associated with angiogenesis inhibitors.

4.
Diabetes ; 71(6): 1282-1298, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35275988

RESUMO

Excessive production of renal reactive oxygen species (ROS) plays a major role in diabetic kidney disease (DKD). Here, we provide key findings demonstrating the predominant pathological role of the pro-oxidant enzyme NADPH oxidase 5 (NOX5) in DKD, independent of the previously characterized NOX4 pathway. In patients with diabetes, we found increased expression of renal NOX5 in association with enhanced ROS formation and upregulation of ROS-sensitive factors early growth response 1 (EGR-1), protein kinase C-α (PKC-α), and a key metabolic gene involved in redox balance, thioredoxin-interacting protein (TXNIP). In preclinical models of DKD, overexpression of NOX5 in Nox4-deficient mice enhances kidney damage by increasing albuminuria and augmenting renal fibrosis and inflammation via enhanced ROS formation and the modulation of EGR1, TXNIP, ERK1/2, PKC-α, and PKC-ε. In addition, the only first-in-class NOX inhibitor, GKT137831, appears to be ineffective in the presence of NOX5 expression in diabetes. In vitro, silencing of NOX5 in human mesangial cells attenuated upregulation of EGR1, PKC-α, and TXNIP induced by high glucose levels, as well as markers of inflammation (TLR4 and MCP-1) and fibrosis (CTGF and collagens I and III) via reduction in ROS formation. Collectively, these findings identify NOX5 as a superior target in human DKD compared with other NOX isoforms such as NOX4, which may have been overinterpreted in previous rodent studies.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Animais , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Fibrose , Humanos , Inflamação/metabolismo , Camundongos , NADPH Oxidase 4/genética , NADPH Oxidase 5/genética , NADPH Oxidase 5/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
Eur Heart J ; 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35296881

RESUMO

AIMS: Hypogonadism is associated with cardiovascular disease. However, the cardiovascular impact of hypogonadism during development is unknown. Using hypospadias as a surrogate of hypogonadism, we investigated whether hypospadias is associated with vascular dysfunction and is a risk factor for cardiovascular disease. METHODS AND RESULTS: Our human study spanned molecular mechanistic to epidemiological investigations. Clinical vascular phenotyping was performed in adolescents with hypospadias and controls. Small subcutaneous arteries from penile skin from boys undergoing hypospadias repair and controls were isolated and functional studies were assessed by myography. Vascular smooth muscle cells were used to assess: Rho kinase, reactive oxygen species (ROS), nitric oxide synthase/nitric oxide, and DNA damage. Systemic oxidative stress was assessed in plasma and urine. Hospital episode data compared men with a history of hypospadias vs. controls. In adolescents with hypospadias, systolic blood pressure (P = 0.005), pulse pressure (P = 0.03), and carotid intima-media thickness standard deviation scores (P = 0.01) were increased. Arteries from boys with hypospadias demonstrated increased U46619-induced vasoconstriction (P = 0.009) and reduced acetylcholine-induced endothelium-dependent (P < 0.0001) and sodium nitroprusside-induced endothelium-independent vasorelaxation (P < 0.0001). Men born with hypospadias were at increased risk of arrhythmia [odds ratio (OR) 2.8, 95% confidence interval (CI) 1.4-5.6, P = 0.003]; hypertension (OR 4.2, 95% CI 1.5-11.9, P = 0.04); and heart failure (OR 1.9, 95% CI 1.7-114.3, P = 0.02). CONCLUSION: Hypospadias is associated with vascular dysfunction and predisposes to hypertension and cardiovascular disease in adulthood. Underlying mechanisms involve perturbed Rho kinase- and Nox5/ROS-dependent signalling. Our novel findings delineate molecular mechanisms of vascular injury in hypogonadism, and identify hypospadias as a cardiovascular risk factor in males. KEY QUESTION: Is hypospadias associated with vascular dysfunction? KEY FINDING: Boys with hypospadias have evidence of hypercontractility and impaired vasodilation secondary to increased Rho kinase activation and oxidative stress. This leads to raised systolic blood pressure in adolescence and increased risk of admission to hospital for cardiovascular diseases in adulthood. TAKE-HOME MESSAGE: Hypospadias is a risk factor for cardiovascular dysfunction in males.

6.
Hypertension ; 79(6): 1145-1146, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35298238
8.
J Physiol ; 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35306667

RESUMO

Exosomes, which are membrane-bound extracellular vesicles (EVs), are generated in the endosomal compartment of almost all eukaryotic cells. They are formed upon the fusion of multivesicular bodies and the plasma membrane and carry proteins, nucleic acids, lipids and other cellular constituents from their parent cells. Multiple factors influence their production including cell stress and injury, humoral factors, circulating toxins, and oxidative stress. They play an important role in intercellular communication, through their ability to transfer their cargo (proteins, lipids, RNAs) from one cell to another. Exosomes have been implicated in the pathophysiology of various diseases including cardiovascular disease (CVD), cancer, kidney disease, and inflammatory conditions. In addition, circulating exosomes may act as biomarkers for diagnostic and prognostic strategies for several pathological processes. In particular exosome-containing miRNAs have been suggested as biomarkers for the diagnosis and prognosis of myocardial injury, stroke and endothelial dysfunction. They may also have therapeutic potential, acting as vectors to deliver therapies in a targeted manner, such as the delivery of protective miRNAs. Transfection techniques are in development to load exosomes with desired cargo, such as proteins or miRNAs, to achieve up-regulation in the host cell or tissue. These advances in the field have the potential to assist in the detection and monitoring progress of a disease in patients during its early clinical stages, as well as targeted drug delivery.

9.
PLoS One ; 17(2): e0264136, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35176122

RESUMO

Current research on hypertension utilizes more than fifty animal models that rely mainly on stable increases in systolic blood pressure. In experimental hypertension, grading or scoring of glomerulopathy in the majority of studies is based on a wide range of opinion-based histological changes that do not necessarily comply with lesional descriptors for glomerular injury that are well-established in clinical pathology. Here, we provide a critical appraisal of experimental hypertensive glomerulopathy with the same approach used to assess hypertensive glomerulopathy in humans. Four hypertensive models with varying pathogenesis were analyzed-chronic angiotensin II infused mice, mice expressing active human renin in the liver (TTRhRen), spontaneously hypertensive rats (SHR), and Goldblatt two-kidney one-clip rats (2K1C). Analysis of glomerulopathy utilized the same criteria applied in humans-hyalinosis, focal segmental glomerulosclerosis (FSGS), ischemic, hypertrophic and solidified glomeruli, or global glomerulosclerosis (GGS). Data from animal models were compared to human reference values. Kidneys in TTRhRen mice, SHR and the nonclipped kidneys in 2K1C rats had no sign of hyalinosis, FSGS or GGS. Glomerulopathy in these groups was limited to variations in mesangial and capillary compartment volumes, with mild increases in collagen deposition. Histopathology in angiotensin II infused mice corresponded to mesangioproliferative glomerulonephritis, but not hypertensive glomerulosclerosis. The number of nephrons was significantly reduced in TTRhRen mice and SHR, but did not correlate with severity of glomerulopathy. The most substantial human-like glomerulosclerotic lesions, including FSGS, ischemic obsolescent glomeruli and GGS, were found in the clipped kidneys of 2K1C rats. The comparison of affected kidneys to healthy control in animals produces lesion values that are numerically impressive but correspond to mild damage if compared to humans. Animal studies should be standardized by employing the criteria and classifications established in human pathology to make experimental and human data fully comparable for comprehensive analysis and model improvements.


Assuntos
Angiotensina II/toxicidade , Modelos Animais de Doenças , Glomerulosclerose Segmentar e Focal/patologia , Hipertensão Renal/patologia , Hipertensão/complicações , Nefrite/patologia , Nefroesclerose/patologia , Animais , Glomerulosclerose Segmentar e Focal/etiologia , Glomerulosclerose Segmentar e Focal/metabolismo , Humanos , Hipertensão/induzido quimicamente , Hipertensão Renal/etiologia , Hipertensão Renal/metabolismo , Masculino , Nefrite/etiologia , Nefrite/metabolismo , Nefroesclerose/etiologia , Nefroesclerose/metabolismo , Ratos , Ratos Endogâmicos SHR , Vasoconstritores/toxicidade
10.
Cardiovasc Res ; 118(5): 1359-1373, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-34320175

RESUMO

AIMS: NOX-derived reactive oxygen species (ROS) are mediators of signalling pathways implicated in vascular smooth muscle cell (VSMC) dysfunction in hypertension. Among the numerous redox-sensitive kinases important in VSMC regulation is c-Src. However, mechanisms linking NOX/ROS to c-Src are unclear, especially in the context of oxidative stress in hypertension. Here, we investigated the role of NOX-induced oxidative stress in VSMCs in human hypertension focusing on NOX5, and explored c-Src, as a putative intermediate connecting NOX5-ROS to downstream effector targets underlying VSMC dysfunction. METHODS AND RESULTS: VSMC from arteries from normotensive (NT) and hypertensive (HT) subjects were studied. NOX1,2,4,5 expression, ROS generation, oxidation/phosphorylation of signalling molecules, and actin polymerization and migration were assessed in the absence and presence of NOX5 (melittin) and Src (PP2) inhibitors. NOX5 and p22phox-dependent NOXs (NOX1-4) were down-regulated using NOX5 siRNA and p22phox-siRNA approaches. As proof of concept in intact vessels, vascular function was assessed by myography in transgenic mice expressing human NOX5 in a VSMC-specific manner. In HT VSMCs, NOX5 was up-regulated, with associated oxidative stress, hyperoxidation (c-Src, peroxiredoxin, DJ-1), and hyperphosphorylation (c-Src, PKC, ERK1/2, MLC20) of signalling molecules. NOX5 siRNA reduced ROS generation in NT and HT subjects. NOX5 siRNA, but not p22phox-siRNA, blunted c-Src phosphorylation in HT VSMCs. NOX5 siRNA reduced phosphorylation of MLC20 and FAK in NT and HT. In p22phox- silenced HT VSMCs, Ang II-induced phosphorylation of MLC20 was increased, effects blocked by melittin and PP2. NOX5 and c-Src inhibition attenuated actin polymerization and migration in HT VSMCs. In NOX5 transgenic mice, vascular hypercontractilty was decreased by melittin and PP2. CONCLUSION: We define NOX5/ROS/c-Src as a novel feedforward signalling network in human VSMCs. Amplification of this system in hypertension contributes to VSMC dysfunction. Dampening the NOX5/ROS/c-Src pathway may ameliorate hypertension-associated vascular injury.


Assuntos
Hipertensão , Músculo Liso Vascular , Actinas/metabolismo , Angiotensina II/metabolismo , Animais , Células Cultivadas , Humanos , Meliteno/metabolismo , Meliteno/farmacologia , Camundongos , Camundongos Transgênicos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , NADPH Oxidase 5/genética , NADPH Oxidase 5/metabolismo , NADPH Oxidase 5/farmacologia , Oxirredução , Proteínas Tirosina Quinases/metabolismo , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo
11.
J Hum Hypertens ; 36(2): 120-125, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34230581

RESUMO

Sex hormone receptors are expressed throughout the vasculature and play an important role in the modulation of blood pressure in health and disease. The functions of these receptors may be important in the understanding of sexual dimorphism observed in the pathophysiology of both hypertension and vascular ageing. The interconnectivity of these factors can be exemplified in postmenopausal females, who with age and estrogen deprivation, surpass males with regard to hypertension prevalence, despite experiencing significantly less disease burden in their estrogen replete youth. Estrogen and androgen receptors mediate their actions via direct genomic effects or rapid non-genomic signaling, involving a host of mediators. The expression and subtype composition of these receptors changes through the lifespan in response to age, disease and hormonal exposure. These factors may promote sex steroid receptor-mediated alterations to the Renin-Angiotensin-Aldosterone System (RAAS), and increases in oxidative stress and inflammation, thereby contributing to the development of hypertension and vascular injury with age.


Assuntos
Hipertensão , Receptores de Esteroides , Adolescente , Envelhecimento , Aldosterona/metabolismo , Feminino , Humanos , Masculino , Receptores de Esteroides/metabolismo , Sistema Renina-Angiotensina/fisiologia
12.
Clin Sci (Lond) ; 135(23): 2661-2663, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34881389

RESUMO

Dramatic improvements in cancer survival have arisen because of the rapid development of novel anti-cancer therapies. The potential for cardiovascular toxicity associated with these drugs often reflects overlap between pathogenic cancer mechanisms and physiological pathways required for normal cardiovascular function. Clinical Science has, therefore, compiled a themed collection on Cardiovascular-Oncology. This collection examines the intersection between cancer treatments and their potentially harmful cardiovascular effects. By defining the mechanisms underlying unwanted cardiovascular effects of anti-cancer therapies, cardioprotective strategies can be developed. Only by doing so, will patients be able to achieve optimal cancer treatment at the minimum cost to cardiovascular health.


Assuntos
Antineoplásicos/efeitos adversos , Cardiotoxicidade/prevenção & controle , Neoplasias/tratamento farmacológico , Antraciclinas/efeitos adversos , Cardiotoxicidade/etiologia , Humanos , Imunoterapia , Terapia de Alvo Molecular
13.
Sci Transl Med ; 13(624): eabg8117, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34910546

RESUMO

Lipotoxicity is a recognized pathological trigger and accelerator of nonalcoholic steatohepatitis (NASH). However, the molecular basis of lipotoxicity-induced NASH remains elusive. Here, we systematically mapped the changes in hepatic transcriptomic landscapes in response to lipotoxic insults across multiple species. Conserved and robust activation of the arachidonic acid pathway, in particular the arachidonate 12-lipoxygenase (ALOX12) gene, was closely correlated with NASH severity in humans, macaques with spontaneously developed NASH, as well as swine and mouse dietary NASH models. Using gain- and loss-of-function studies, we found that ALOX12 markedly exacerbated NASH in both mice and Bama pig models. ALOX12 was shown to induce NASH by directly targeting acetyl-CoA carboxylase 1 (ACC1) via a lysosomal degradation mechanism. Overall, our findings reveal a key molecular driver of NASH pathogenesis and suggest that ALOX12-ACC1 interaction may be a therapeutic target in NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Modelos Animais de Doenças , Fígado/metabolismo , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Suínos
14.
Sci Transl Med ; 13(624): eabg8116, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34910548

RESUMO

Nonalcoholic steatohepatitis (NASH) is a progressive liver disease and has become a leading indication for liver transplantation in the United States. The development of effective therapies for NASH is a major unmet need. Here, we identified a small molecule, IMA-1, that can treat NASH by interrupting the arachidonate 12-lipoxygenase (ALOX12)­acetyl-CoA carboxylase 1 (ACC1) interaction. IMA-1 markedly blocked diet-induced NASH progression in both male mice and Cynomolgus macaque therapeutic models. The anti-NASH efficacy of IMA-1 was comparable to ACC inhibitor in both species. Protein docking simulations and following functional experiments suggested that the anti-NASH effects of IMA-1 were largely dependent on its direct binding to a pocket in ALOX12 proximal to its ACC1-interacting surface instead of inhibiting ALOX12 lipoxygenase activity. IMA-1 treatment did not elicit hyperlipidemia, a known side effect of direct inhibition of ACC enzymatic activity, in both mice and macaques. These findings provide proof of concept across multiple species for the use of small molecule­based therapies for NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Acetil-CoA Carboxilase , Animais , Fígado/metabolismo , Macaca/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo
15.
PLoS One ; 16(11): e0260283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34793553

RESUMO

SARS-CoV-2 viral attachment and entry into host cells is mediated by a direct interaction between viral spike glycoproteins and membrane bound angiotensin-converting enzyme 2 (ACE2). The receptor binding motif (RBM), located within the S1 subunit of the spike protein, incorporates the majority of known ACE2 contact residues responsible for high affinity binding and associated virulence. Observation of existing crystal structures of the SARS-CoV-2 receptor binding domain (SRBD)-ACE2 interface, combined with peptide array screening, allowed us to define a series of linear native RBM-derived peptides that were selected as potential antiviral decoy sequences with the aim of directly binding ACE2 and attenuating viral cell entry. RBM1 (16mer): S443KVGGNYNYLYRLFRK458, RBM2A (25mer): E484GFNCYFPLQSYGFQPTNGVGYQPY508, RBM2B (20mer): F456NCYFPLQSYGFQPTNGVGY505 and RBM2A-Sc (25mer): NYGLQGSPFGYQETPYPFCNFVQYG. Data from fluorescence polarisation experiments suggested direct binding between RBM peptides and ACE2, with binding affinities ranging from the high nM to low µM range (Kd = 0.207-1.206 µM). However, the RBM peptides demonstrated only modest effects in preventing SRBD internalisation and showed no antiviral activity in a spike protein trimer neutralisation assay. The RBM peptides also failed to suppress S1-protein mediated inflammation in an endogenously expressing ACE2 human cell line. We conclude that linear native RBM-derived peptides are unable to outcompete viral spike protein for binding to ACE2 and therefore represent a suboptimal approach to inhibiting SARS-CoV-2 viral cell entry. These findings reinforce the notion that larger biologics (such as soluble ACE2, 'miniproteins', nanobodies and antibodies) are likely better suited as SARS-CoV-2 cell-entry inhibitors than short-sequence linear peptides.


Assuntos
Enzima de Conversão de Angiotensina 2/imunologia , Antivirais/farmacologia , Peptídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/imunologia , Internalização do Vírus , Células A549 , Humanos , Domínios e Motivos de Interação entre Proteínas
16.
Cardiovasc Res ; 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34672341

RESUMO

AIMS: Interferon-stimulated gene 15 (ISG15) encodes an 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-defense response to microbial infection; however, its contribution to vascular damage associated to 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 angiotensinII (AngII)-treated vascular cells and macrophages. Proteomics revealed differential expression of proteins implicated in cardiovascular function, extracellular matrix and remodeling, and vascular redox state in aorta from AngII-infused ISG15-/- mice. Moreover, ISG15-/- mice were protected against AngII-induced hypertension, vascular stiffness, elastin remodeling, 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 remodeling. CONCLUSION: ISG15 is a novel mediator of vascular damage in hypertension through oxidative stress and inflammation. TRANSLATIONAL PERSPECTIVE: Recent evidence from randomized clinical trials demonstrate the effectiveness of specific anti-inflammatory treatments in cardiovascular prevention. In this study we have identified a new inflammatory mediator involved in vascular damage in experimental and human hypertension and aneurysms. We found that interferon stimulated gene 15 (ISG15) is increased at the vascular level in animal models of hypertension and aneurysms. More importantly, ISG15 correlates with human hypertension, vascular remodeling, and aneurysms presence. Underlying mechanisms responsible for vascular damage induced by ISG15 include oxidative and inflammation. Our results further support the role of inflammation in vascular damage in different cardiovascular pathologies.

19.
Clin Sci (Lond) ; 135(15): 1845-1858, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34269800

RESUMO

OBJECTIVE: The mechanisms involved in NOX5 activation in atherosclerotic processes are not completely understood. The present study tested the hypothesis that lysophosphatidylcholine (LPC), a proatherogenic component of oxLDL, induces endothelial calcium influx, which drives NOX5-dependent reactive oxygen species (ROS) production, oxidative stress, and endothelial cell dysfunction. APPROACH: Human aortic endothelial cells (HAEC) were stimulated with LPC (10-5 M, for different time points). Pharmacological inhibition of NOX5 (Melittin, 10-7 M) and NOX5 gene silencing (siRNA) was used to determine the role of NOX5-dependent ROS production in endothelial oxidative stress induced by LPC. ROS production was determined by lucigenin assay and electron paramagnetic spectroscopy (EPR), calcium transients by Fluo4 fluorimetry, and NOX5 activity and protein expression by pharmacological assays and immunoblotting, respectively. RESULTS: LPC increased ROS generation in endothelial cells at short (15 min) and long (4 h) stimulation times. LPC-induced ROS was abolished by a selective NOX5 inhibitor and by NOX5 siRNA. NOX1/4 dual inhibition and selective NOX1 inhibition only decreased ROS generation at 4 h. LPC increased HAEC intracellular calcium, important for NOX5 activation, and this was blocked by nifedipine and thapsigargin. Bapta-AM, selective Ca2+ chelator, prevented LPC-induced ROS production. NOX5 knockdown decreased LPC-induced ICAM-1 mRNA expression and monocyte adhesion to endothelial cells. CONCLUSION: These results suggest that NOX5, by mechanisms linked to increased intracellular calcium, is key to early LPC-induced endothelial oxidative stress and pro-inflammatory processes. Since these are essential events in the formation and progression of atherosclerotic lesions, the present study highlights an important role for NOX5 in atherosclerosis.


Assuntos
Aterosclerose/enzimologia , Células Endoteliais/efeitos dos fármacos , Lisofosfatidilcolinas/toxicidade , NADPH Oxidase 5/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Aterosclerose/patologia , Cálcio/metabolismo , Sinalização do Cálcio , Adesão Celular , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais/enzimologia , Células Endoteliais/patologia , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Monócitos/metabolismo , NADPH Oxidase 5/antagonistas & inibidores , NADPH Oxidase 5/genética , Interferência de RNA
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