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Gaucher disease (GD) has a high carrier rate among Ashkenazi Jews.The most common disease-causing variant in this population N370S, is also prevalent pan-ethnically. This has led to speculations of some protective effect for carriers of this variant. During the recent COVID-19 pandemic, GD patients reportedly had a surprisingly low infection rate and mild symptoms considering their disease status. As SARS-CoV-2 gains entry into the cell via membrane-bound angiotensin-converting enzyme 2 (ACE2), we speculated that differences in levels of soluble ACE2 in GD patients could contribute to this protective state. While ACE is known to be elevated in GD, to our knowledge, ACE2 levels have not been explored. We measured serum and macrophage-bound levels of ACE and ACE2 by ELISA and western blot, respectively, in GD patients and age- and sex-matched controls. Our results reveal a significant elevation of both serum and macrophage-bound ACE and ACE2 in GD patients compared to healthy controls. This elevation appears to be mitigated by GD treatment. Moreover, the most robust ACE2 elevation was observed in N370S homozygotes, and was not effected by treatment. Since coronaviruses use the ACE2 receptor as a gateway for host cell entry, we speculate that elevated circulating ACE2 may serve as a decoy. This might explain the observed mild infections in GD patients during the COVID-19 pandemic.
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Enzima de Conversão de Angiotensina 2 , COVID-19 , Doença de Gaucher , Genótipo , Peptidil Dipeptidase A , SARS-CoV-2 , Humanos , Doença de Gaucher/genética , Doença de Gaucher/sangue , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/sangue , Enzima de Conversão de Angiotensina 2/metabolismo , Masculino , Feminino , COVID-19/sangue , COVID-19/genética , COVID-19/virologia , Adulto , Pessoa de Meia-Idade , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/sangue , Macrófagos/metabolismo , Idoso , Adulto Jovem , Estudos de Casos e ControlesRESUMO
The central role of natriuretic peptides (NPs) in the complex cardio-renal integrated physiology and organ failure has been revealed over the last four decades. Atrial natriuretic peptide (ANP), the oldest representative of the NPs family, is produced through conversion of proANP to the mature peptide by corin, a trans-membrane protease localized to the cardiac myocyte membrane. Similarly, brain natriuretic peptide (BNP) is generated by furin, which cleaves proBNP to BNP in myocytes. Though the components of NPs system, their synthesis and target organs are well established, understanding their role in the interplay between the heart and the kidney is steadily evolving. In this context, Feldman et al. (New England Journal of Medicine, 389, 1685) recently described patients with hypertension, cardiomyopathy, atrial arrhythmia and left atrial fibrosis, associated with a homozygous loss-of-function variant of the gene encoding corin (Cor-/-). Notably, reduced baseline urinary electrolyte and creatinine excretion have been observed in one of the studied patients. This renal excretory functional impairment could be attributed to the lack of cardiac-derived ANP in these patients, as implied by Feldman et al. Yet, in this mini-review we suggest that this aberrant renal manifestation may principally stem from lack of local ANP production at renal tissue, as corin is normally expressed in proximal tubules, Henle's loop and collecting ducts, with locally produced ANP provoking Na+ and water exertion. Collectively, it seems that beside the classic well-established cardio-renal axis, the renal NPs system functions as local endocrine machinery in the regulation of sodium excretion.
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Rim , Serina Endopeptidases , Humanos , Animais , Rim/metabolismo , Serina Endopeptidases/metabolismo , Serina Endopeptidases/genética , Fator Natriurético Atrial/metabolismo , Fator Natriurético Atrial/genética , Coração/fisiologiaRESUMO
Congestive heart failure (CHF) is often associated with impaired kidney function. Over- activation of the renin-angiotensin-aldosterone system (RAAS) contributes to avid salt/water retention and cardiac hypertrophy in CHF. While the deleterious effects of angiotensin II (Ang II) in CHF are well established, the biological actions of angiotensin 1-7 (Ang 1-7) are not fully characterized. In this study, we assessed the acute effects of Ang 1-7 (0.3, 3, 30 and 300 ng/kg/min, IV) on urinary flow (UF), urinary Na+ excretion (UNaV), glomerular filtration rate (GFR) and renal plasma flow )RPF) in rats with CHF induced by the placement of aortocaval fistula. Additionally, the chronic effects of Ang 1-7 (24 µg/kg/h, via intra-peritoneally implanted osmotic minipumps) on kidney function, cardiac hypertrophy and neurohormonal status were studied. Acute infusion of either Ang 1-7 or its agonist, AVE 0991, into sham controls, but not CHF rats, increased UF, UNaV, GFR, RPF and urinary cGMP. In the chronic protocols, untreated CHF rats displayed lower cumulative UF and UNaV than their sham controls. Chronic administration of Ang 1-7 and AVE 0991 exerted significant diuretic, natriuretic and kaliuretic effects in CHF rats, but not in sham controls. Serum creatinine and aldosterone levels were significantly higher in vehicle-treated CHF rats as compared with controls. Treatment with Ang 1-7 and AVE 0991 reduced these parameters to comparable levels observed in sham controls. Notably, chronic administration of Ang 1-7 to CHF rats reduced cardiac hypertrophy. In conclusion, Ang 1-7 exerts beneficial renal and cardiac effects in rats with CHF. Thus, we postulate that ACE2/Ang 1-7 axis represents a compensatory response to over-activity of ACE/AngII/AT1R system characterizing CHF and suggest that Ang 1-7 may be a potential therapeutic agent in this disease state.
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Insuficiência Cardíaca , Ratos , Animais , Rim/metabolismo , Angiotensina I/farmacologia , Angiotensina I/metabolismo , Fragmentos de Peptídeos/metabolismo , Cardiomegalia/metabolismo , Sistema Renina-Angiotensina , Angiotensina II/metabolismoRESUMO
BACKGROUND: Non-alcoholic fatty liver disease affects up to 30% of adults in the USA, and is associated with a higher incidence of chronic liver morbidity and mortality. Several molecular pathways are involved in the pathology of liver steatosis, including lipid uptake, lipogenesis, lipolysis, and beta-oxidation. The enzyme heparanase has been implicated in liver steatosis. Herein, we investigated the effect of heparanase inhibition on liver steatosis in E0 mice. METHODS: In vivo experiments: Male wild-type mice fed with either chow diet (n = 4) or high-fat diet (n = 6), and male E0 mice fed with chow diet (n = 8) or high-fat diet (n = 33) were included. Mice on a high-fat diet were treated for 12 weeks with PG545 at low dose (6.4 mg/kg/week, ip, n = 6) or high dose (13.3 mg/kg/week, ip, n = 7), SST0001 (1.2 mg/mouse/day, ip, n = 6), or normal saline (control, n = 14). Animals were sacrificed two days after inducing peritonitis. Serum was analyzed for biochemical parameters. Mouse peritoneal macrophages (MPMs) were harvested and analyzed for lipid content. Livers were harvested for histopathological analysis of steatosis, lipid content, and the expression of steatosis-related factors at the mRNA level. In vitro experiments: MPMs were isolated from untreated E0 mice aged 8-10 weeks and were cultured and treated with either PG545 or SST0001, both at 50 µg/mL for 24 h, followed by assessment of mRNA expression of steatosis related factors. RESULTS: Heparanase inhibition significantly attenuated the development of liver steatosis, as was evident by liver histology and lipid content. Serum analysis indicated lowering of cholesterol and triglycerides levels in mice treated with heparanase inhibitors. In liver tissue, assessment of mRNA expression of key factors in lipid uptake, lipolysis, lipogenesis, and beta-oxidation exhibited significant downregulation following PG545 treatment and to a lesser extent when SST0001 was applied. However, in vitro treatment of MPMs with PG545, but not SST0001, resulted in increased lipid content in these cells, which is opposed to their effect on MPMs of treated mice. This may indicate distinct regulatory pathways in the system or isolated macrophages following heparanase inhibition. CONCLUSION: Heparanase inhibition significantly attenuates the development of liver steatosis by decreasing tissue lipid content and by affecting the mRNA expression of key lipid metabolism regulators.
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BACKGROUND: Superb microvascular imaging (SMI) is an innovative ultrasound image processing technique that provides greater detail and better visualization of small branching vessels. We assume that SMI will provide sufficient information regarding the severity of chronic kidney disease (CKD) and reflecting histological changes. AIMS: The aims was to assess the capabilities of SMI imaging regarding the early detection of kidney dysfunction and renal fibrosis in comparison to the reference standard renal biopsy for the early diagnosis of kidney fibrosis. METHODS: SMI was performed in patients (n = 52) with CKD stage 2-5, where some of them underwent biopsy proven CKD and fibrosis as part of the diagnosis. In addition, biochemical tests were performed, including kidney function tests, urine collection for proteinuria, and the estimation of GFR by MDRD or CKD-EPI eGFR in CKD patients and healthy controls (n = 17). All subjects underwent SMI, where vascularity is expressed as the SMI index (a low index reflects low vascularity/fibrosis and vice versa). RESULTS: The SMI vascular index was significantly lower in CKD patients as compared with healthy controls (72.2 ± 12.9 vs. 49.9 ± 16.7%, p < 0.01). Notably, a moderate correlation between the SMI index and eGFR was found among the CKD patients (r = 0.56, p < 0.001). Similarly, a strong correlation was found between SCr and the SMI index of the diseased subjects (r = -0.54, p < 0.001). In patients who underwent renal biopsy, the SMI index corresponded with the histological alterations and CKD staging. CONCLUSIONS: This study demonstrated that SMI imaging may be utilized in CKD patients of various stages for the evaluation of chronic renal morphological changes and for differentiation between CKD grades.
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Intra-abdominal pressure (IAP) affects cardio-respiratory and hemodynamic parameters and can be measured directly or indirectly by measuring gastric or urinary bladder pressure. The aim of this study was to investigate the correlation between IAP, gastric pressure and urinary bladder pressure in patients with morbid obesity, at normal and elevated levels of IAP in two positions. As well, to examine the effects of increasing IAP and patient's position on hemodynamic and respiratory parameters. Twelve patients undergoing laparoscopic bariatric surgery were included. IAP, gastric pressure, and urinary bladder pressure were measured while patients were in the supine position and after 45° anti-Trendelenburg tilt. Mean inspiratory pressure, peak inspiratory pressure, and tidal volume were recorded and assessed. In supine position; directly measured IAP was 9.1 ± 1.8 mmHg, compared to 10 ± 3.6 and 8.9 ± 2.9 mmHg in the stomach and bladder, respectively. Increasing IAP to 15 mmHg resulted in an increased gastric pressure of 17 ± 3.8 mmHg, and urinary bladder pressure of 14.8 ± 3.9 mmHg. Gastric and urinary bladder pressures strongly correlated with IAP (R = 0.875 and 0.847, respectively). With 45° anti-Trendelenburg tilt; directly measured IAP was 9.4 ± 2.2 mmHg, and pressures of 10.8 ± 3.8 mmHg and 9.2 ± 3.8 mmHg were measured in the stomach and the bladder, respectively. Increasing IAP to 15 mmHg resulted in elevating gastric and bladder pressures to 16.6 ± 5.3 and 13.3 ± 4 mmHg, respectively. Gastric and urinary bladder pressures had good correlation with IAP (R = 0.843 and 0.819, respectively). Changing patient position from supine to 45° anti-Trendelenburg position resulted in decreased mean and peak inspiratory pressures, and increased tidal volume. Basal IAP is high in patients with morbid obesity. IAP shows positive correlation to gastric and urinary bladder pressures at both normal and elevated levels of IAP. Anti-Trendelenburg tilt of mechanically ventilated morbidly obese patients resulted in favorable effects on respiratory parameters.Trial Registration: The study was retrospectively registered in the NIH registry. Registration number is pending.
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Abdome , Obesidade Mórbida , Pressão , Estômago , Bexiga Urinária , Humanos , Obesidade Mórbida/cirurgiaRESUMO
Congestive heart failure (CHF) often leads to progressive cardiac hypertrophy and salt/water retention. However, its pathogenesis remains largely unclarified. Corin, a cardiac serine protease, is responsible for converting proANP and proBNP to biologically active peptides. Although the involvement of corin in cardiac hypertrophy and heart failure was extensively studied, the alterations in corin and proprotein convertase subtilisin/kexin-6 (PCSK6), a key enzyme in the conversion of procorin to corin, has not been studied simultaneously in the cardiac and renal tissues in cardiorenal syndrome. Thus, this study aims to examine the status of PCSK6/corin in the cardiac and renal tissues of rats with CHF induced by the creation of aorto-caval fistula (ACF). We divided rats with ACF into two subgroups based on the pattern of their urinary sodium excretion, namely, compensated and decompensated. Placement of ACF led to cardiac hypertrophy, pulmonary congestion, and renal dysfunction, which were more profound in the decompensated subgroup. Corin immunoreactive peptides were detected in all heart chambers at the myocyte membranal and cytosolic localization and in the renal tissue, especially in the apical membrane of the proximal tubule, mTAL, and the collecting duct. Interestingly, the expression and abundance of corin in both the cardiac ventricles and renal tissues were significantly increased in compensated animals as compared with the decompensated state. Noteworthy, the abundance of PCSK6 in these tissues followed a similar pattern as corin. In contrast, furin expression was upregulated in the cardiac and renal tissues in correlation with CHF severity. We hypothesize that the obtained upregulation of cardiac and renal PCSK6/corin in rats with compensated CHF may represent a compensatory response aiming at maintaining normal Na+ balance, whereas the decline in these two enzymes may contribute to the pathogenesis of avid sodium retention, cardiac hypertrophy, and blunted atrial natriuretic peptide/brain natriuretic peptide actions in decompensated CHF.
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During the current formidable COVID-19 pandemic, it is appealing to address ideas that may invoke therapeutic interventions. Clotting disorders are well recognized in patients infected with severe acute respiratory syndrome (SARS) caused by a novel coronavirus (SARS-CoV-2), which lead to severe complications that worsen the prognosis in these subjects. Increasing evidence implicate Heparan sulfate proteoglycans (HSPGs) and Heparanase in various diseases and pathologies, including hypercoagulability states. Moreover, HSPGs and Heparanase are involved in several viral infections, in which they enhance cell entry and release of the viruses. Herein we discuss the molecular involvement of HSPGs and heparanase in SARS-CoV-2 infection, namely cell entry and release, and the accompanied coagulopathy complications, which assumedly could be blocked by heparanase inhibitors such as Heparin and Pixatimod.
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Transtornos da Coagulação Sanguínea/etiologia , Coagulação Sanguínea , COVID-19/complicações , Glucuronidase/metabolismo , SARS-CoV-2/fisiologia , Animais , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/metabolismo , COVID-19/sangue , COVID-19/metabolismo , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/etiologia , Coagulação Intravascular Disseminada/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Internalização do VírusRESUMO
Na+/H+ exchangers (NHEs), encoded by Solute Carrier 9A (SLC9A) genes in human, are ubiquitous integral membrane ion transporters that mediate the electroneutral exchange of H+ with Na+ or K+. NHEs, found in the kidney and intestine, play a major role in the process of fluid reabsorption together via Na+,K+-ATPase pump and Na+ channels. Nevertheless, the expression pattern of NHE in the lung and its role in alveolar fluid homeostasis has not been addressed. Therefore, we aimed to examine the expression of NHE specific isoforms in alveolar epithelial cells (AECs), and assess their role in congestive heart failure (CHF). Three NHE isoforms were identified in AEC and A549 cell line, at the level of protein and mRNA; NHE1, NHE2 and mainly NHE8, the latter was shown to be localized in the apical membrane of AEC. Treating A549 cells with angiotensin (Ang) II for 3, 5 and 24 hours displayed a significant reduction in NHE8 protein abundance. Moreover, the abundance of NHE8 protein was downregulated in A549 cells that were treated overnight with Ang II. NHE8 abundance in whole lung lysate was increased in rats with 1-week CHF compared to sham operated rats. However, lower abundance of NHE8 was observed in 4-week CHF group. In conclusion, we herein show for the first time, the expression of a novel NHE isoform in AEC, namely NHE8. Notably, Ang II decreased NHE8 protein levels. Moreover, NHE8 was distinctly affected in CHF rats, probably depending on the severity of the heart failure.
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Células Epiteliais Alveolares/metabolismo , Isoformas de Proteínas/metabolismo , Trocador 1 de Sódio-Hidrogênio/metabolismo , Células A549 , Animais , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Regulação para Baixo/fisiologia , Humanos , Intestinos/fisiologia , Rim/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Corona virus disease 2019 (COVID-19) imposes a serious public health pandemic affecting the whole world, as it is spreading exponentially. Besides its high infectivity, SARS-CoV-2 causes multiple serious derangements, where the most prominent is severe acute respiratory syndrome as well as multiple organ dysfunction including heart and kidney injury. While the deleterious impact of SARS-CoV-2 on pulmonary and cardiac systems have attracted remarkable attention, the adverse effects of this virus on the renal system is still underestimated. Kidney susceptibility to SARS-CoV-2 infection is determined by the presence of angiotensin-converting enzyme 2 (ACE2) receptor which is used as port of the viral entry into targeted cells, tissue tropism, pathogenicity and subsequent viral replication. The SARS-CoV-2 cellular entry receptor, ACE2, is widely expressed in proximal epithelial cells, vascular endothelial and smooth muscle cells and podocytes, where it supports kidney integrity and function via the enzymatic production of Angiotensin 1-7 (Ang 1-7), which exerts vasodilatory, anti-inflammatory, antifibrotic and diuretic/natriuretic actions via activation of the Mas receptor axis. Loss of this activity constitutes the potential basis for the renal damage that occurs in COVID-19 patients. Indeed, several studies in a small sample of COVID-19 patients revealed relatively high incidence of acute kidney injury (AKI) among them. Although SARS-CoV-1 -induced AKI was attributed to multiorgan failure and cytokine release syndrome, as the virus was not detectable in the renal tissue of infected patients, SARS-CoV-2 antigens were detected in kidney tubules, suggesting that SARS-CoV-2 infects the human kidney directly, and eventually induces AKI characterized with high morbidity and mortality. The mechanisms underlying this phenomenon are largely unknown. However, the fact that ACE2 plays a crucial role against renal injury, the deprivation of the kidney of this advantageous enzyme, along with local viral replication, probably plays a central role. The current review focuses on the critical role of ACE2 in renal physiology, its involvement in the development of kidney injury during SARS-CoV-2 infection, renal manifestations and therapeutic options. The latter includes exogenous administration of Ang (1-7) as an appealing option, given the high incidence of AKI in this ACE2-depleted disorder, and the benefits of ACE2/Ang1-7 including vasodilation, diuresis, natriuresis, attenuation of inflammation, oxidative stress, cell proliferation, apoptosis and coagulation.
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Congestive heart failure (CHF) is often associated with kidney and pulmonary dysfunction. Activation of the renin-angiotensin-aldosterone system (RAAS) contributes to avid sodium retention, cardiac hypertrophy and oedema formation, including lung congestion. While the status of the classic components of RAAS such as renin, angiotensin converting enzyme (ACE), angiotensin II (Ang II) and angiotensin II receptor AT-1 is well studied in CHF, the expression of angiotensin converting enzyme-2 (ACE2), a key enzyme of angiotensin 1-7 (Ang 1-7) generation in the pulmonary, cardiac and renal systems has not been studied thoroughly in this clinical setting. This issue is of a special interest as Ang 1-7 counterbalance the vasoconstrictory, pro-inflammatory and pro-proliferative actions of Ang II. Furthermore, CHF predisposes to COVID-19 disease severity, while ACE2 also serves as the binding domain of SARS-CoV-2 in human host-cells, and acts in concert with furin, an important enzyme in the synthesis of BNP in CHF, in permeating viral functionality along TMPRSST2. ADAM17 governs ACE2 shedding from cell membranes. Therefore, the present study was designed to investigate the expression of ACE2, furin, TMPRSS2 and ADAM17 in the lung, heart and kidneys of rats with CHF to understand the exaggerated susceptibility of clinical CHF to COVID-19 disease. Heart failure was induced in male Sprague Dawley rats by the creation of a surgical aorto-caval fistula. Sham-operated rats served as controls. One week after surgery, the animals were subdivided into compensated and decompensated CHF according to urinary sodium excretion. Both groups and their controls were sacrificed, and their hearts, lungs and kidneys were harvested for assessment of tissue remodelling and ACE2, furin, TMPRSS2 and ADAM17 immunoreactivity, expression and immunohistochemical staining. ACE2 immunoreactivity and mRNA levels increased in pulmonary, cardiac and renal tissues of compensated, but not in decompensated CHF. Furin immunoreactivity was increased in both compensated and decompensated CHF in the pulmonary, cardiac tissues and renal cortex but not in the medulla. Interestingly, both the expression and abundance of pulmonary, cardiac and renal TMPRSS2 decreased in CHF in correlation with the severity of the disease. Pulmonary, cardiac and renal ADAM17 mRNA levels were also downregulated in decompensated CHF. Circulating furin levels increased in proportion to CHF severity, whereas plasma ACE2 remained unchanged. In summary, ACE2 and furin are overexpressed in the pulmonary, cardiac and renal tissues of compensated and to a lesser extent of decompensated CHF as compared with their sham controls. The increased expression of the ACE2 in heart failure may serve as a compensatory mechanism, counterbalancing the over-activity of the deleterious isoform, ACE. Downregulated ADAM17 might enhance membranal ACE2 in COVID-19 disease, whereas the suppression of TMPRSS2 in CHF argues against its involvement in the exaggerated susceptibility of CHF patients to SARS-CoV2.
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Proteína ADAM17/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Furina/metabolismo , Insuficiência Cardíaca/metabolismo , Serina Endopeptidases/metabolismo , Proteína ADAM17/genética , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/genética , COVID-19/metabolismo , COVID-19/virologia , Modelos Animais de Doenças , Expressão Gênica , Insuficiência Cardíaca/genética , Humanos , Rim/metabolismo , Pulmão/metabolismo , Masculino , Miocárdio/metabolismo , Ratos Sprague-Dawley , Sistema Renina-Angiotensina/fisiologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Serina Endopeptidases/genéticaRESUMO
Endothelial dysfunction (ED) is a key feature of diabetes and is a major cause of diabetic vasculopathy. Diabetic patients who also exhibit hyperlipidaemia suffer from accelerated vascular complications. While the deleterious effects of high glucose levels (HG) and hyperlipidaemia alone on ED are well established, the effects of combined hyperlipidaemia and HG have not been thoroughly studied. Therefore, the current study examines whether HG and hyperlipidaemia exert synergistic ED, and explores the mechanisms underlying this phenomenon. We applied multi-disciplinary approaches including cultured HUVECs and HMEC-1 as well as knockout mice CByJ.129S7(B6)-Ldlrtm1Her/J (LDLR-/- ) to investigate the mechanisms underlying combined HG and hyperlipidaemia-induced ED. Incremental doses of glucose in the presence or absence of OxLDL were added to HUVECs and HMEC-1. After 5 days, the status of nitric oxide (NO) and endothelin (ET)-1 systems as well as their signal transduction were assessed using Western blot, ELISA and immunoreactive staining. The effects of chronic combination of HG and hyperlipidaemia on endothelial integrity and function as well as alterations in circulatory NO and ET-1 systems were examined in knockout mice LDLR-/- and their wild-type. HUVEC cells exposed to HG and OxLDL displayed enhanced ET-1 production, more than HG or OxLDL when added alone. Overproduction of ET-1 stems from up-regulation of endothelin converting enzyme (ECE)-1 as observed under these conditions. In contrast, combination of HG and OxLDL dramatically decreased both total endothelial NO synthase (eNOS) by 60%, and activated eNOS (peNOS) by 80%. Moreover, NRF2 decreased by 42% and its active form (pNRF2) by 56%, as compared to baseline. Likewise, ETB levels decreased by 64% from baseline on endothelial cells. Furthermore, diabetic LDLR-/- mice displayed a higher blood pressure, plasma triglycerides, cholesterol, ET-1 and NO2/NO3 levels, when compared with normoglycemic LDLR-/- and BALB mice. Combined hyperglycaemia and hyperlipidaemia activates the ET system and attenuates the nitric oxide system with the Nrf2 signalling pathway. These findings suggest that perturbations in these paracrine systems may contribute to ED.
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Endotélio/metabolismo , Hiperglicemia/metabolismo , Hiperlipidemias/metabolismo , Animais , Biomarcadores , Movimento Celular , Células Cultivadas , Modelos Animais de Doenças , Suscetibilidade a Doenças , Endotelinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hiperglicemia/etiologia , Hiperlipidemias/etiologia , Lipoproteínas LDL/metabolismo , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico/metabolismoRESUMO
Engulfed by the grave consequences of the coronavirus disease 2019 (COVID-19) pandemic, a better understanding of the unique pattern of viral invasion and virulence is of utmost importance. Angiotensin (Ang)-converting enzyme (ACE) 2 is a key component in COVID-19 infection. Expressed on cell membranes in target pulmonary and intestinal host cells, ACE2 serves as an anchor for initial viral homing, binding to COVID-19 spike-protein domains to enable viral entry into cells and subsequent replication. Viral attachment is facilitated by a multiplicity of membranal and circulating proteases that further uncover attachment loci. Inherent or acquired enhancement of membrane ACE2 expression, likely leads to a higher degree of infection and may explain the predisposition to severe disease among males, diabetics, or patients with respiratory or cardiac diseases. Additionally, once attached, viral intracellular translocation and replication leads to depletion of membranal ACE2 through degradation and shedding. ACE2 generates Ang 1-7, which serves a critical role in counterbalancing the vasoconstrictive, pro-inflammatory, and pro-coagulant effects of ACE-induced Ang II. Therefore, Ang 1-7 may decline in tissues infected by COVID-19, leading to unopposed deleterious outcomes of Ang II. This likely leads to microcirculatory derangement with endothelial damage, profound inflammation, and coagulopathy that characterize the more severe clinical manifestations of COVID-19 infection. Our understanding of COVID-ACE2 associations is incomplete, and some conceptual formulations are currently speculative, leading to controversies over issues such as the usage of ACE inhibitors or Ang-receptor blockers (ARBs). This highlights the importance of focusing on ACE2 physiology in the evaluation and management of COVID-19 disease.
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BACKGROUND: IgA nephropathy (IgAN) is characterized by proteinuria, hypertension, and decreased glomerular filtration rate at the time of diagnosis. However, the underlying mechanism is still obscure. The impact of haptoglobin (Hp) phenotype, as a genetic risk factor, on the progression of IgAN has not been studied yet. The current study examines whether Hp phenotype influences IgAN progression and response to treatment. MATERIALS AND METHODS: The study included 40 patients with IgAN, 26 non-IgAN chronic kidney disease (CKD), 114 patients on hemodialysis, and 150 healthy subjects. Blood and urine samples were collected at baseline and 6 months after initiation therapy. Serum creatinine, total proteinuria, and Hp phenotype were determined in all patients and healthy controls. RESULTS: Approximately 17% of IgAN patients were Hp 1-1, 40% Hp 2-1, and 42.5% Hp 2-2. In contrast, in non-IgAN CKD patients, the prevalence of Hp 1-1, Hp 2-1, and Hp 2-2 was 8%, 19%, and 73%, respectively. In hemodialytic patients, prevalence of Hp 1-1, Hp 2-1, and Hp 2-2 was 10.5, 49.1, and 40.4%, respectively. In healthy subjects, the distribution of Hp 1-1, Hp 2-1, and Hp 2-2 was 7, 39, and 54%, respectively. Interestingly, IgAN Hp 2-2 and Hp 2-1 patients were more stable and responded better to treatment with routine therapy than other patients with Hp phenotype. CONCLUSION: The prevalence of Hp 1-1 phenotype is higher in IgAN patients than in the general population in Israel, and even more than in patients with CKD or subjects on hemodialysis. Patients with Hp 2-2 exhibited a better renal response to the routine therapies.
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Glomerulonefrite por IGA/genética , Haptoglobinas/genética , Adulto , Idoso , Progressão da Doença , Feminino , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/etiologia , Glomerulonefrite por IGA/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos ProspectivosRESUMO
BACKGROUND: Minimally invasive surgery is considered the gold-standard approach for many surgical procedures. However, it requires CO2 insufflation and elevated intra-abdominal pressure (IAP), which may result in adverse pulmonary, cardiovascular, gastrointestinal, and renal changes. The kidneys are highly sensitive to pressure changes, where risk factors such as severe infection, dehydration, older age, and chronic kidney disease may aggravate the likelihood for the development of acute kidney injury (AKI). Unfortunately, the impact of diabetes mellitus on the deleterious effects of elevated IAP-induced AKI was not fully studied so far. The present study was designed to examine the effect of pneumoperitoneum on renal function and the development of AKI in diabetic rats. MATERIALS AND METHODS: Sprague Dawley rats were divided into 2 groups: control (nondiabetic) rats (n=7) and diabetic rats (n=10). A Veress needle was introduced through the supravesical incision where inflating CO2 allowing the IAP to be increased to the desired pressures 7, 10, and 14 mm Hg for 45 minutes each and at the end of the experiment, the pressure was deflated to zero. During each pressure point, hemodynamic parameters were recorded and urine and blood samples were collected for analysis. RESULTS: The baseline values of renal hemodynamic were significantly lower in diabetic rats. There were no major statistically significant changes from baseline in urinary flow, urinary sodium excretion (UNaV), glomerular filtration rate, and renal plasma flow during 7 mm Hg pressure in both groups. When the IAP was further elevated, a significant deterioration of these parameters was recorded. This trend was more pronounced among diabetic rats. When examining urinary neutrophil gelatinase-associated lipocalin, a linear correlation was observed between the IAP and the biomarker level. This correlation was more significant in the diabetic group. CONCLUSION: The present study demonstrated a direct correlation between IAP elevation and the development of AKI. Diabetic rats were more sensitive to the deleterious effect of pneumoperitoneum, where urinary neutrophil gelatinase-associated lipocalin levels may be used as a future biomarker to predict postoperative AKI, especially in patients with diabetes.
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Injúria Renal Aguda , Diabetes Mellitus Experimental , Insuflação , Pneumoperitônio , Injúria Renal Aguda/etiologia , Idoso , Animais , Diabetes Mellitus Experimental/complicações , Humanos , Rim , Pneumoperitônio/etiologia , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVES: Corin is a protease that converts pro-atrial natriuretic peptide (pro-ANP) to ANP. While the involvement of ANP in the cardiovascular regulation is well established, there is increasing evidence that the pregnant uterus produces ANP, which promotes spiral artery remodeling. The present study examines the alterations in corin and PCSK6, a key enzyme in the conversion of pro-corin to corin, in the placenta of hyperinsulinemic dams (HD) featuring pregnancy-induced hypertension (PIH). MATERIALS AND METHODS: The study was conducted on female Wistar rats. Rats were rendered hyperinsulinemic by subcutaneous insulin pellet, mated and followed to the twenty-first day of pregnancy. Normal pregnant dams (NPD) served as controls. Both groups were sacrificed on day 21 of gestation and their placentas were dissected along with the mesometrial triangle (MT). The tissue was then sectioned from the maternal surface to the base of the MT, and processed for histological and molecular biology analysis of Corin, PCSK6 and ANP expression/immunoreactivity. RESULTS: Hyperinsulinemic dams developed PIH, along lower placental and fetal weights. Corin expression and immunoreactivity were significantly decreased in the placenta by ~40-50%, but not in the MT. Similarly, placental but not MT PCSK6 immunoreactivity was lower in HD. Concomitantly with the downregulation of corin/PCSK6, proANP levels increased in the placenta of HD. CONCLUSIONS: Corin and PCSK6 are expressed in the placenta and MT. The decline in these two enzymes in the placenta of HD suggests a role of corin/PCSK6 machinery in the development of PIH and intrauterine growth restriction characterizing hyperinsulinemia.