RESUMEN
BACKGROUND: Immune checkpoint blockade (ICB) has made remarkable achievements, but newly identified armored and cold tumors cannot respond to ICB therapy. The high prevalence of concomitant medications has huge impact on immunotherapeutic responses, but the clinical effects on the therapeutic outcome of armored and cold tumors are still unclear. METHODS: In this research, using large-scale transcriptomics datasets, the expression and potential biological functions of angiotensin II receptor 1 (AGTR1), the target of angiotensin receptor blocker (ARB), were investigated. Next, the roles of ARB in tumor cells and tumor microenvironment cells were defined by a series of in vitro and in vivo assays. In addition, the clinical impacts of ARB on ICB therapy were assessed by multicenter cohorts and meta-analysis. RESULTS: AGTR1 was overexpressed in armored and cold tumors and associated with poor response to ICB therapy. ARB, the inhibitor for AGTR1, only suppressed the aggressiveness of tumor cells with high AGTR1 expression, which accounted for a very small proportion. Further analysis revealed that AGTR1 was always highly expressed in cancer-associated fibroblasts (CAFs) and ARB inhibited type I collagen expression in CAFs by suppressing the RhoA-YAP axis. Moreover, ARB could also drastically reverse the phenotype of armored and cold to soft and hot in vivo, leading to a higher response to ICB therapy. In addition, both our in-house cohorts and meta-analysis further supported the idea that ARB can significantly enhance ICB efficacy. CONCLUSION: Overall, we identify AGTR1 as a novel target in armored and cold tumors and demonstrate the improved therapeutic efficacy of ICB in combination with ARB. These findings could provide novel clinical insight into how to treat patients with refractory armored and cold tumors.
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Antagonistas de Receptores de Angiotensina , Inhibidores de Puntos de Control Inmunológico , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Antagonistas de Receptores de Angiotensina/farmacología , Animales , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/genética , Microambiente Tumoral , Línea Celular Tumoral , FemeninoRESUMEN
HLA donor specific antibodies (DSA) are implicated in antibody-mediated rejection (AMR), graft dysfunction and failure in kidney transplant (KT) recipients. Non-HLA antibodies including angiotensin II type 1 receptor (AT1R) may also play a role in AMR, impact graft function and survival. Data is limited in paediatric KT cohorts. We aimed to assess the prevalence and effect of pre-transplant AT1R antibodies on rejection, graft function and survival in paediatric KT recipients. This was a retrospective cohort study conducted across two paediatric centres including KT recipients with a pre-transplant AT1R antibody level. Outcomes included rejection, de novo DSA formation, graft function, failure, proteinuria and hypertension. Of 71 individuals, 72% recorded a positive pre-transplant AT1R Ab level (≥17 U/mL). Over a median follow-up of 4.7 years, AT1R Ab positivity demonstrated a trend towards increased risk of rejection however was not statistically significant (HR 3.45, 95% CI 0.97-12.35, p-value 0.06). Sensitivity analysis with AT1R Ab levels of ≥25 U/mL (HR 2.05 95% CI 0.78-5.39, p-value 0.14) and ≥40 U/mL (HR 1.32, CI 95% 0.55-3.17, p-value 0.53) validated this. De novo DSA formation occurred more frequently with AT1R Ab positivity (41% vs. 20%, p-value 0.9). AT1R Ab was not associated with hypertension, proteinuria, graft failure or dysfunction. In conclusion, this cohort study demonstrated a high prevalence of pre-transplant AT1R Ab positivity (72%). AT1R Ab positivity demonstrated a trend towards increased risk of rejection and de novo DSA formation however did not meet statistical significance. There was no association between AT1R Ab and hypertension, proteinuria, graft failure or dysfunction.
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Rechazo de Injerto , Supervivencia de Injerto , Trasplante de Riñón , Receptor de Angiotensina Tipo 1 , Humanos , Receptor de Angiotensina Tipo 1/inmunología , Rechazo de Injerto/inmunología , Masculino , Estudios Retrospectivos , Femenino , Niño , Adolescente , Isoanticuerpos/sangre , Isoanticuerpos/inmunología , Preescolar , Antígenos HLA/inmunología , Proteinuria/inmunología , Proteinuria/sangre , Hipertensión/inmunología , Hipertensión/fisiopatología , Hipertensión/sangreRESUMEN
OBJECTIVE: Aim: To investigate lipid profile parameters depending the polymorphism of the A1166C I type gene receptor of the angiotensin II as a predictor of arterial hypertension. PATIENTS AND METHODS: Materials and Methods: The study involved 86 patients with arterial hypertension. The control group consisted of 30 practically healthy individuals. Indicators of lipid metabolism in the blood serum of patients were determined using "Lachema" kits on an analyzer. The the polymorphism of the A1166C I type gene receptor of the angiotensin II was studied by polymerase chain reaction with electrophoretic detection of the results. RESULTS: Results: Higher levels of total cholesterol were found in patients with CC genotype compared to AA genotype carriers ((8.94±0.09) vs (5.18±0.02) mmol/L). The level of low-density lipoprotein in CC-genotype carriers was (7.43±0.03) versus (3.66±0.02) mmol/L in A-allele homozygotes. Triglycerides and very low density lipoproteins were also significantly higher in CC genotype carriers compared to patients with AA genotype. The level of high-density lipoprotein was lower in homozygotes with C-allele than in patients with the AA genotype, and was (0.59±0.12) versus (0.99±0.03) mmol/L. CONCLUSION: Conclusions: The presence in the CC genotype the I type gene receptor of the angiotensin II type is a predictor of dyslipidemia. In patients with arterial hypertension, the presence in the C-allele of the I type gene of the angiotensin II type contributes to a significant increase in serum adipokines and a decrease in ghrelin levels.
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Hipertensión , Polimorfismo Genético , Receptor de Angiotensina Tipo 1 , Humanos , Hipertensión/genética , Hipertensión/sangre , Masculino , Femenino , Receptor de Angiotensina Tipo 1/genética , Persona de Mediana Edad , Lípidos/sangre , Adulto , GenotipoRESUMEN
The renin-angiotensin system plays a key role in regulating blood pressure, which has motivated many investigations of associated mouse models of hypertensive arterial remodelling. Such studies typically focus on histological and cell biological changes, not wall mechanics. This study explores tissue-level ramifications of chronic angiotensin II infusion in wild-type (WT) and type 1b angiotensin II (AngII) receptor null (Agtr1b -/-) mice. Biaxial biomechanical and immunohistological changes were quantified and compared in the thoracic and abdominal aorta in these mice following 14 and 28 days of angiotensin II infusion. Preliminary results showed that changes were largely independent of sex. Associated thickening and stiffening of the aortic wall in male mice differed significantly between thoracic and abdominal regions and between genotypes. Notwithstanding multiple biomechanical changes in both WT and Agtr1b -/- mice, AngII infusion caused distinctive wall thickening and inflammation in the descending thoracic aorta of WT, but not Agtr1b -/-, mice. Our study underscores the importance of exploring differential roles of receptor-dependent angiotensin II signalling along the aorta and its influence on distinct cell types involved in regional histomechanical remodelling. Disrupting the AT1b receptor primarily affected inflammatory cell responses and smooth muscle contractility, suggesting potential therapeutic targets.
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Angiotensina II , Ratones Noqueados , Receptor de Angiotensina Tipo 1 , Remodelación Vascular , Animales , Angiotensina II/farmacología , Angiotensina II/metabolismo , Ratones , Masculino , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/genética , Femenino , Aorta Torácica/metabolismo , Aorta Torácica/patologíaRESUMEN
Albuminuria is characterized by a disruption of the glomerular filtration barrier, which is composed of the fenestrated endothelium, the glomerular basement membrane, and the slit diaphragm. Nephrin is a major component of the slit diaphragm. Apart from hemodynamic effects, Ang II enhances albuminuria by ß-Arrestin2-mediated nephrin endocytosis. Blocking the AT1 receptor with candesartan and irbesartan reduces the Ang II-mediated nephrin-ß-Arrestin2 interaction. The inhibition of MAPK ERK 1/2 blocks Ang II-enhanced nephrin-ß-Arrestin2 binding. ERK 1/2 signaling, which follows AT1 receptor activation, is mediated by G-protein signaling, EGFR transactivation, and ß-Arrestin2 recruitment. A mutant AT1 receptor defective in EGFR transactivation and ß-Arrestin2 recruitment reduces the Ang II-mediated increase in nephrin ß-Arrestin2 binding. The mutation of ß-Arrestin2K11,K12, critical for AT1 receptor binding, completely abrogates the interaction with nephrin, independent of Ang II stimulation. ß-Arrestin2K11R,K12R does not influence nephrin cell surface expression. The data presented here deepen our molecular understanding of a blood-pressure-independent molecular mechanism of AT-1 receptor blockers (ARBs) in reducing albuminuria.
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Angiotensina II , Endocitosis , Proteínas de la Membrana , Receptor de Angiotensina Tipo 1 , Endocitosis/efectos de los fármacos , Endocitosis/fisiología , Animales , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Angiotensina II/farmacología , Angiotensina II/metabolismo , Humanos , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Ratones , Albuminuria/metabolismo , Podocitos/metabolismo , Podocitos/efectos de los fármacos , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/genética , Compuestos de Bifenilo/farmacología , Irbesartán/farmacología , Células HEK293 , Arrestina beta 2/metabolismo , Arrestina beta 2/genética , Bencimidazoles , TetrazolesRESUMEN
Activation of the renin-angiotensin-aldosterone system (RAAS) plays an important pathophysiological role in hypertension. Increased mRNA levels of the angiotensinogen angiotensin-converting enzyme, angiotensin type 1 receptor gene, Agtr1a, and the aldosterone synthase gene, CYP11B2, have been reported in the heart, blood vessels, and kidneys in salt-sensitive hypertension. However, the mechanism of gene regulation in each component of the RAAS in cardiovascular and renal tissues is unclear. Epigenetic mechanisms, which are important for regulating gene expression, include DNA methylation, histone post-translational modifications, and microRNA (miRNA) regulation. A close association exists between low DNA methylation at CEBP-binding sites and increased AGT expression in visceral adipose tissue and the heart of salt-sensitive hypertensive rats. Several miRNAs influence AGT expression and are associated with cardiovascular diseases. Expression of both ACE and ACE2 genes is regulated by DNA methylation, histone modifications, and miRNAs. Expression of both angiotensinogen and CYP11B2 is reversibly regulated by epigenetic modifications and is related to salt-sensitive hypertension. The mineralocorticoid receptor (MR) exists in cardiovascular and renal tissues, in which many miRNAs influence expression and contribute to the pathogenesis of hypertension. Expression of the 11beta-hydroxysteroid dehydrogenase type 2 (HSD11B2) gene is also regulated by methylation and miRNAs. Epigenetic regulation of renal and vascular HSD11B2 is an important pathogenetic mechanism for salt-sensitive hypertension.
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Metilación de ADN , Epigénesis Genética , Hipertensión , Sistema Renina-Angiotensina , Sistema Renina-Angiotensina/genética , Hipertensión/genética , Hipertensión/metabolismo , Animales , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Angiotensinógeno/genética , Angiotensinógeno/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Receptor de Angiotensina Tipo 1/genética , Receptor de Angiotensina Tipo 1/metabolismo , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismoRESUMEN
Coronary artery disease (CAD) is the leading cause of death in India. Many genetic polymorphisms play a role in regulating oxidative stress, blood pressure and lipid metabolism, contributing to the pathophysiology of CAD. This study examined the association between ten polymorphisms and CAD in the Jat Sikh population from Northern India, also considering polygenic risk scores. This study included 177 CAD cases and 175 healthy controls. The genetic information of GSTM1 (rs366631), GSTT1 (rs17856199), ACE (rs4646994), AGT M235T (rs699), AGT T174M (rs4762), AGTR1 A1166C (rs5186), APOA5 (rs3135506), APOC3 (rs5128), APOE (rs7412) and APOE (rs429358) and clinical information was collated. Statistical analyses were performed using SPSS version 27.0 and SNPstats. Significant independent associations were found for GST*M1, GST*T1, ACE, AGT M235T, AGT T174M, AGTR1 A1166C and APOA5 polymorphisms and CAD risk (all p < 0.05). The AGT CT haplotype was significantly associated with a higher CAD risk, even after controlling for covariates (adjusted OR = 3.93, 95% CI [2.39-6.48], p < 0.0001). The APOA5/C3 CC haplotype was also significantly associated with CAD (adjusted OR = 1.86, 95% CI [1.14-3.03], p < 0.05). A higher polygenic risk score was associated with increased CAD risk (adjusted OR = 1.98, 95% CI [1.68-2.34], p < 0.001). Seven polymorphisms were independently associated with an increase in the risk of CAD in this North Indian population. A considerable risk association of AGT, APOA5/C3 haplotypes and higher genetic risk scores is documented, which may have implications for clinical and public health applications.
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Angiotensinógeno , Apolipoproteína A-V , Apolipoproteínas E , Enfermedad de la Arteria Coronaria , Puntuación de Riesgo Genético , Glutatión Transferasa , Polimorfismo de Nucleótido Simple , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Angiotensinógeno/genética , Apolipoproteína A-V/genética , Apolipoproteína C-III , Apolipoproteínas E/genética , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/genética , Enfermedad de la Arteria Coronaria/epidemiología , Frecuencia de los Genes , Estudios de Asociación Genética , Glutatión Transferasa/genética , Haplotipos , India/epidemiología , Peptidil-Dipeptidasa A/genética , Receptor de Angiotensina Tipo 1/genética , Factores de RiesgoRESUMEN
We evaluated the concentration of AT2R antibodies in 136 patients with primary and secondary glomerular diseases: membranous nephropathy (n = 18), focal and segmental glomerulosclerosis (n = 25), systemic lupus erythematosus (n = 17), immunoglobulin A (IgA) nephropathy (n = 14), mesangial (non-IgA) proliferative nephropathy (n = 6), c-ANCA vasculitis (n = 40), perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) vasculitis (n = 16), and compared it with a healthy control group (22 patients). Serum creatinine levels, proteinuria, serum albumin, and total protein concentrations were prospectively recorded for 2 years. The mean levels of AT2R antibodies in the lupus nephropathy group were significantly higher compared to the control group, 64.12 ± 26.95 units/mL and 9.72 ± 11.88 units/mL, respectively. There was no association between this level and the clinical course of the disease. The AT2R levels in other kinds of glomerular disease were no different from the control group. We found significant correlations between AT1R and AT2R in patients with membranous nephropathy (r = 0.66), IgA nephropathy (r = 0.61), and c-ANCA vasculitis (r = 0.63). Levels of AT2R antibodies in systemic lupus erythematosus are higher compared to other types of glomerulonephritis, vasculitis, and a healthy control group. Levels of AT2R antibodies correlate with AT1R antibodies in the groups of patients with membranous nephropathy, IgA nephropathy, and c-ANCA vasculitis. These kinds of AT2R antibodies have a stimulative effect on AT2R, but we have not found the influence of these antibodies on the clinical course of glomerular diseases.
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Autoanticuerpos , Receptor de Angiotensina Tipo 2 , Humanos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Receptor de Angiotensina Tipo 2/inmunología , Receptor de Angiotensina Tipo 2/metabolismo , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Anciano , Glomérulos Renales/inmunología , Glomérulos Renales/patología , Glomerulonefritis Membranosa/inmunología , Glomerulonefritis Membranosa/sangre , Glomerulonefritis/inmunología , Glomerulonefritis/sangre , Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Anticuerpos Anticitoplasma de Neutrófilos/sangre , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/sangre , Glomerulonefritis por IGA/inmunología , Glomerulonefritis por IGA/sangre , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/inmunología , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/sangre , Nefritis Lúpica/inmunología , Receptor de Angiotensina Tipo 1/inmunología , Adulto Joven , Enfermedades Renales/inmunologíaRESUMEN
Hypertension is the most prevalent non-communicable disease, affecting billions of people worldwide. Discovery and development of natural antihypertensive lead compounds or drugs are important to resolve the limitations of existing antihypertensive drug safety and resistance. This investigation verified that carnosic acid (CA), an important active ingredient of rosemary, an edible spice plant, indicates a significant anti-hypertensive activity in spontaneous hypertension rats by targeting AT1R. Moreover, our research indicated that CA shared a comparable antagonistic mechanism with established synthetic angiotensin II receptor blockers (ARBs), as it occupies the binding sites of Angiotensin II (AngII) at His6 and Pro7 within the AT1R's ligand-binding pocket. Notably, CA exerted better anti-hypertensive activity since it could not break the Asn1113.35-Asn2957.46 hydrogen bond to stabilize the AT1R inactive state. As the first potent AT1R antagonist identified in a natural food source, CA is poised to become a novel anti-hypertensive lead compound, distinguished by its unique skeleton structure different from conventional ARBs. This research lays a valuable theoretical groundwork for the future exploration of CA and rosemary extract in both fundamental studies and clinical applications.
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Abietanos , Antihipertensivos , Hipertensión , Abietanos/farmacología , Abietanos/química , Animales , Ratas , Antihipertensivos/química , Antihipertensivos/farmacología , Hipertensión/tratamiento farmacológico , Bloqueadores del Receptor Tipo 1 de Angiotensina II/química , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Masculino , Receptor de Angiotensina Tipo 1/metabolismo , Simulación del Acoplamiento Molecular , Ratas Endogámicas SHR , Presión Sanguínea/efectos de los fármacos , Sitios de UniónRESUMEN
Objective. Genetic factors substantially contribute to the development and duration of arterial hypertension. The study of the A1166C polymorphism of the angiotensin II type 1 receptor gene (AGTR1) in arterial hypertension is an auspicious area for assessing the relationship between heredity, hypertension development, and adipokines, but it still remains debatable. The purpose of the current study was to investigate serum adipokines levels depending on the AGTR1 A1166C polymorphism. Methods. A total of 86 patients with arterial hypertension were examined, who underwent the evaluation of the allelic A1166C polymorphism of AGTR1 by polymerase chain reaction with electrophoretic detection and determination of serum adipokines levels using enzyme-linked immunosorbent assay. Results. In the group of patients with arterial hypertension, a significant increase in serum adipokines (resistin, adiponectin, and leptin) levels was found against the background of a decrease in the antianorexic hormone ghrelin with a predominance of CC genotype carriers compared with AA genotype carriers of the AGTR1. A statistically significant decrease in ghrelin and an increase in serum adipokines (resistin, adiponectin, and leptin) in CC genotype carriers compared with AA genotype carriers of the AGTR1 were found suggesting that CC genotype carriers may be predictors of the development of arterial hypertension in our patients. Conclusions. Statistically significant decrease in ghrelin and increase in serum adipokines (resistin, adiponectin, and leptin) were found in CC genotype carriers compared with AA genotype carriers of the AGTR1, which suggests that carriers of the CC genotype are predictors of the arterial hypertension development in our patients.
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Adipoquinas , Hipertensión , Receptor de Angiotensina Tipo 1 , Humanos , Receptor de Angiotensina Tipo 1/genética , Femenino , Masculino , Hipertensión/genética , Hipertensión/sangre , Persona de Mediana Edad , Adipoquinas/sangre , Adipoquinas/genética , Adulto , Leptina/sangre , Leptina/genética , Polimorfismo de Nucleótido Simple , Adiponectina/sangre , Adiponectina/genética , Anciano , Ghrelina/genética , Ghrelina/sangre , Genotipo , Predisposición Genética a la Enfermedad , Resistina/genética , Resistina/sangreRESUMEN
OBJECTIVES: To investigate the effect of dexamethasone (DXM) on acute lung and kidney injury with sepsis and its possible mechanism. METHODS: Control (NC), lipopolysaccharide (LPS) and lipopolysaccharide + dexamethasone (LPS+DXM) treated groups were established by random assignment of 72 Wistar rats. The NC rats were injected with physiological saline, while the LPS group was injected with LPS (5 mg/kg) and LPS+DXM group was injected with LPS(5 mg/kg) first and followed by DXM (1 mg/kg). Serum tumor necrosis factor-α (TNF-α) and serum macrophage inflammatory protein 1α (MIP-1α) were measured by ELISA. Lung wet/dry weight ratio, serum creatinine(SCR) and blood urea nitrogen(BUN) were determined at various time points. Hematoxylin Eosin staining (HE) for pathological changes in the lung and kidney. Radioimmunoassay was used to detect the levels of angiotensin II (Ang II) in plasma, lung and kidney tissues. Immunohistochemistry and western blot (WB) were used to detect angiotensin II receptor type 1 (AT1R) protein and angiotensin II receptor type 2 (AT2R) protein in lung and kidney tissues. The level of nitric oxide (NO) in serum, lung and kidney were detected using nitrate reductase method. RESULTS: Compared with control group, serum TNF-α, MIP-1α, SCR, BUN, lung W/D, Ang II level in plasma, lung and kidney, lung and kidney AT2R protein, NO level in serum, lung and kidney were significantly elevated(P<0.05) and pathological damage of lung and kidney tissues were showed in LPS group rats (P<0.05), whereas DXM down-regulated the above indexes and alleviate pathological damage of lung and kidney tissues. However, the expression of the lung and kidney AT1R protein was opposite to the above results. CONCLUSIONS: Sepsis can cause acute lung and kidney injury and changes RAAS components in circulating, lung and renal. DXM can improve acute lung and kidney injury in septic rats, and the mechanism may be related to the down-regulation of inflammatory factors, AngII, AT2R, NO and up-regulation of AT1R expression by DXM.
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Angiotensina II , Dexametasona , Ratas Wistar , Sepsis , Animales , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Sepsis/metabolismo , Dexametasona/farmacología , Ratas , Masculino , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/sangre , Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/etiología , Lesión Renal Aguda/patología , Lesión Renal Aguda/prevención & control , Pulmón/patología , Pulmón/metabolismo , Pulmón/efectos de los fármacos , Lipopolisacáridos , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/patología , Lesión Pulmonar Aguda/prevención & control , Riñón/patología , Riñón/efectos de los fármacos , Riñón/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Óxido Nítrico/metabolismo , Receptor de Angiotensina Tipo 2/metabolismo , Nitrógeno de la Urea SanguíneaRESUMEN
Different ligands stabilize specific conformations of the angiotensin II type 1 receptor (AT1R) that direct distinct signaling cascades mediated by heterotrimeric G proteins or ß-arrestin. These different active conformations are thought to engage distinct intracellular transducers because of differential phosphorylation patterns in the receptor C-terminal tail (the "barcode" hypothesis). Here, we identified the AT1R barcodes for the endogenous agonist AngII, which stimulates both G protein activation and ß-arrestin recruitment, and for a synthetic biased agonist that only stimulates ß-arrestin recruitment. The endogenous and ß-arrestin-biased agonists induced two different ensembles of phosphorylation sites along the C-terminal tail. The phosphorylation of eight serine and threonine residues in the proximal and middle portions of the tail was required for full ß-arrestin functionality, whereas phosphorylation of the serine and threonine residues in the distal portion of the tail had little influence on ß-arrestin function. Similarly, molecular dynamics simulations showed that the proximal and middle clusters of phosphorylated residues were critical for stable ß-arrestin-receptor interactions. These findings demonstrate that ligands that stabilize different receptor conformations induce different phosphorylation clusters in the C-terminal tail as barcodes to evoke distinct receptor-transducer engagement, receptor trafficking, and signaling.
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Receptor de Angiotensina Tipo 1 , Transducción de Señal , beta-Arrestinas , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/química , Receptor de Angiotensina Tipo 1/genética , Fosforilación , Humanos , beta-Arrestinas/metabolismo , beta-Arrestinas/genética , Células HEK293 , Simulación de Dinámica Molecular , Angiotensina II/metabolismoRESUMEN
AIMS: Transactivation of insulin-growth-factor-receptor (IGF-1R) by angiotensin-II-type-1-receptor (AT-1R) was only demonstrated in vascular-smooth-muscle cells and has never been tested in breast-cancer (BC). This investigation addressed the impact of chronic AT-1R blockade by valsartan (Val) on possible concurrent AT-1R/IGF-1R signaling inhibition, regressing BC-tumor-microenvironment (TME) cellular components activation, and hindering BC development. MAIN METHODS: The effect of different Val doses (10, 20, 40 & 80 mg/kg/day for 490 days) was tested on dimethylbenz(a)anthracene (DMBA)-induced progesterone-promoted-BC in rats. The influence on intratumoral/circulating angiotensin-II (ANG-II) levels and AT-1R/Mas-R immunofluorescent-expression were assessed. The potential AT-1R/IGF-1R crosstalk within TME-BC-stem-cells (BCSCs) and cancer-associated-fibroblasts (CAFs) was evaluated by fluorescently marking these cells and locating the immunofluorescently-stained AT-1R/IGF-1R in them using confocal-laser-microscopy and further quantified by flow cytometry. In addition, the molecular alterations following blocking AT-1R were inspected including determining Src; crucial for IGF-1R transactivation by AT-1R, Notch-1; IGF-IR transcriptional-regulator, and PI3K/Akt &IL-6/STAT expression. Further, the suppression of CSCs' capabilities to maintain pluripotency, stemness features, epithelial-to-mesenchymal-transition (EMT), and angiogenesis was evaluated by assessing NANOG gene, aldehyde-dehydrogenase (ALDH), N-cadherin and vascular-endothelial-growth-factor (VEGF), respectively. Furthermore, the proliferative marker; Ki-67, was detected by immunostaining, and tumors were histologically graded using Elston-Ellis-modified-Scarff-Bloom-Richardson method. KEY FINDINGS: Prophylactic Val significantly reduced tumor size, prolonged latency, reduced tumor histopathologic grade, decreased circulating/intratumoral-ANG-II levels, increased Mas-R, and decreased AT1R expression. AT-1R/IGF-1R were co-expressed with a high correlation coefficient on CAFs/BCSCs. Moreover, Val significantly attenuated IGF-1R transactivation and transcriptional regulation via Src and Notch-1 genes' downregulation and reduced Src/IGF-IR-associated PI3K/Akt and IL-6/STAT3 signaling. Further, Val significantly decreased intratumoral NANOG, ALDH, N-cadherin, VEGF, and Ki-67 levels. SIGNIFICANCE: Chronic Val administration carries a potential for repurposing as adjuvant or conjunct therapy for patients at high risk for BC.
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Bloqueadores del Receptor Tipo 1 de Angiotensina II , Neoplasias de la Mama , Receptor de Angiotensina Tipo 1 , Receptor IGF Tipo 1 , Microambiente Tumoral , Valsartán , Animales , Femenino , Ratas , Valsartán/farmacología , Receptor de Angiotensina Tipo 1/metabolismo , Receptor IGF Tipo 1/metabolismo , Microambiente Tumoral/efectos de los fármacos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Ratas Sprague-DawleyRESUMEN
Angiotensin-II (Ang-II) production is driven by deviations in blood volume and osmolality, and serves the role of regulating blood pressure and fluid intake to maintain cardiovascular and hydromineral homeostasis. These actions are mediated by Ang-II acting on its type 1a receptor (AT1aR) within the central nervous system and periphery. Of relevance, AT1aR are expressed on sensory afferents responsible for conveying cardiovascular information to the nucleus of the solitary tract (NTS). We have previously determined that optical excitation of neurons and vagal afferents within the NTS that express AT1aR (referred to as NTSAT1aR) mimics the perception of increased vascular stretch and induces compensatory responses to restore blood pressure. Here, we test whether NTSAT1aR are also involved in the modulation of water and sodium intake. We directed the light-sensitive excitatory channelrhodopsin-2 (ChR2) or inhibitory halorhodopsin (Halo) to Agtr1a-containing neurons and measured water and sodium chloride (NaCl) intake in the presence and absence of optical stimulation within the NTS during various challenges to fluid homeostasis. Optical perturbation of NTSAT1aR modulates NaCl intake, such that excitation attenuates, whereas inhibition increases intake. This effect is only observed in the water-deprived condition, suggesting that NTSAT1aR are involved in the regulation of sodium intake during an imbalance in both the intracellular and extracellular fluid compartments. Furthermore, optical excitation of NTSAT1aR increases c-Fos expression within oxytocinergic neurons of the paraventricular nucleus of the hypothalamus (PVN), indicating that the regulation of sodium intake by NTSAT1aR may be mediated by oxytocin. Collectively, these results reveal that NTSAT1aR are sufficient and necessary to modulate sodium intake relative to perceived changes in vascular stretch.
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Neuronas , Receptor de Angiotensina Tipo 1 , Núcleo Solitario , Animales , Núcleo Solitario/metabolismo , Núcleo Solitario/fisiología , Núcleo Solitario/efectos de los fármacos , Receptor de Angiotensina Tipo 1/metabolismo , Neuronas/metabolismo , Neuronas/fisiología , Masculino , Ingestión de Líquidos/fisiología , Ingestión de Líquidos/efectos de los fármacos , Neuronas Aferentes/fisiología , Neuronas Aferentes/metabolismo , Optogenética , Cloruro de Sodio/farmacologíaRESUMEN
Acupuncture can reduce blood pressure, heart rate (HR), and ameliorate cardiac damage by modulating the excitability of the sympathetic nervous system, but the exact mechanism of this effect remains unclear. This study investigated the potential mechanisms of acupuncture in the treatment of cardiac damage in hypertension. Spontaneously hypertensive rats (SHR) were used as the hypertension model with Wistar-Kyoto rats as the control. Manual acupuncture, electroacupuncture, and metoprolol were used as interventions. Systolic and diastolic blood pressure (SBP, DBP) plus HR were monitored with cardiac structure determined using Masson staining. Angiotensin II (Ang II) and norepinephrine in myocardium were detected with ELISA as was Ang(1-7) and gamma aminobutyric acid (GABA) in the rostral ventrolateral medulla (RVLM). Expression of mRNA for collagen type I (Col-I), Col-III, actin α1 (ACTA1), and thrombospondin 4 (THBS4) in myocardium was detected using real-time PCR. Expression of angiotensin converting enzyme (ACE), Ang II, angiotensin II type 1 receptor (AT1R), ACE2, and Mas receptor (MasR) proteins in RVLM was monitored using western blot. After manual acupuncture and electroacupuncture treatment, SHRs showed decreased SBP, DBP and HR, reduced myocardial damage. There was decreased expression of the ACE/Ang II/AT1R axis, and increased expression of the ACE2/Ang(1-7)/MasR axis within the RVLM. GABA levels were increased within the RVLM and norepinephrine levels were decreased in myocardial tissue. Metoprolol was more effective than either manual acupuncture or electroacupuncture. Acupuncture directed against hypertensive cardiac damage may be associated with regulation of ACE/Ang II/AT1R and the ACE2/Ang(1-7)/MasR pathway within the RLVM to reduce cardiac sympathetic excitability.
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Terapia por Acupuntura , Angiotensina II , Angiotensina I , Enzima Convertidora de Angiotensina 2 , Hipertensión , Bulbo Raquídeo , Fragmentos de Péptidos , Peptidil-Dipeptidasa A , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Receptor de Angiotensina Tipo 1 , Animales , Angiotensina I/metabolismo , Hipertensión/metabolismo , Hipertensión/terapia , Fragmentos de Péptidos/metabolismo , Enzima Convertidora de Angiotensina 2/metabolismo , Masculino , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/genética , Bulbo Raquídeo/metabolismo , Angiotensina II/metabolismo , Terapia por Acupuntura/métodos , Peptidil-Dipeptidasa A/metabolismo , Peptidil-Dipeptidasa A/genética , Proto-Oncogenes Mas , Sistema Nervioso Simpático/metabolismo , Ratas , Proteínas Proto-Oncogénicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Presión Sanguínea/fisiología , Transducción de Señal/fisiologíaRESUMEN
It is well-established that dysfunction of megalin-mediated albumin endocytosis by proximal tubule epithelial cells (PTECs) and the activation of the Renin-Angiotensin System (RAS) play significant roles in the development of Diabetic Kidney Disease (DKD). However, the precise correlation between these factors still requires further investigation. In this study, we aimed to elucidate the potential role of angiotensin II (Ang II), a known effector of RAS, as the mediator of albumin endocytosis dysfunction induced by high glucose (HG) in PTECs. To achieve this, we utilized LLC-PK1 and HK-2 cells, which are well-established in vitro models of PTECs. Using albumin-FITC or DQ-albumin as tracers, we observed that incubation of LLC-PK1 and HK-2 cells with HG (25 mM for 48 h) significantly reduced canonical receptor-mediated albumin endocytosis, primarily due to the decrease in megalin expression. HG increased the concentration of Ang II in the LLC-PK1 cell supernatant, a phenomenon associated with an increase in angiotensin-converting enzyme (ACE) expression and a decrease in prolyl carboxypeptidase (PRCP) expression. ACE type 2 (ACE2) expression remained unchanged. To investigate the potential impact of Ang II on HG effects, the cells were co-incubated with angiotensin receptor inhibitors. Only co-incubation with 10-7 M losartan (an antagonist for type 1 angiotensin receptor, AT1R) attenuated the inhibitory effect of HG on albumin endocytosis, as well as megalin expression. Our findings contribute to understanding the genesis of tubular albuminuria observed in the early stages of DKD, which involves the activation of the Ang II/AT1R axis by HG.
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Albúminas , Angiotensina II , Endocitosis , Células Epiteliales , Glucosa , Túbulos Renales Proximales , Receptor de Angiotensina Tipo 1 , Endocitosis/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Túbulos Renales Proximales/efectos de los fármacos , Angiotensina II/farmacología , Glucosa/metabolismo , Glucosa/farmacología , Receptor de Angiotensina Tipo 1/metabolismo , Animales , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Humanos , Albúminas/metabolismo , Porcinos , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Sistema Renina-Angiotensina/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Línea Celular , Losartán/farmacologíaRESUMEN
Hypertension is a globally prevalent disease, but the pathogenesis remains largely unclear. AMP-activated protein kinase (AMPK) is a nutrition-sensitive signal of cellular energy metabolism, which has a certain influence on the development of hypertension. Previously, we found a down-regulation of the phosphorylated (p-) form of AMPK, and the up-regulation of the angiotensin II type 1 receptor (AT1-R) and that of p-ERK1/2 in the hypothalamic paraventricular nucleus (PVN) of hypertensive rats. However, the exact mechanism underlying the relationship between AMPK and AT1-R in the PVN during hypertension remains unclear. Thus, we hypothesized that AMPK modulates AT1-R through the ERK1/2-NF-κB pathway in the PVN, thereby inhibiting sympathetic nerve activity and improving hypertension. To examine this hypothesis, we employed a renovascular hypertensive animal model developed via two-kidney, one-clip (2K1C) and sham-operated (SHAM). Artificial cerebrospinal fluid (aCSF), used as vehicle, or 5-amino-1-ß-D-ribofuranosyl-imidazole-4-carboxamide (AICAR, an AMPK activator, 60 µg/day) was microinjected bilaterally in the PVN of these rats for 4 weeks. In 2K1C rats, there an increase in systolic blood pressure (SBP) and circulating norepinephrine (NE). Also, the hypertensive rats had lowered expression of p-AMPK and p-AMPK/AMPK, elevated expression of p-ERK1/2, p-ERK1/2/ERK1/2 and AT1-R, increased NF-κB p65 activity in the PVN compared with the levels of these biomarkers in SHAM rats. Four weeks of bilateral PVN injection of AMPK activator AICAR, attenuated the NE level and SBP, increased the expression of p-AMPK and p-AMPK/AMPK, lessened the NF-κB p65 activity, decreased the expression of p-ERK1/2, p-ERK1/2/ERK1/2 and AT1-R in the PVN of 2K1C rats. Data from this study imply that the activation of AMPK within the PVN suppressed AT1-R expression through inhibiting the ERK1/2-NF-κB pathway, decreased the activity of the sympathetic nervous system, improved hypertension.
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Proteínas Quinasas Activadas por AMP , Modelos Animales de Enfermedad , Activación Enzimática , Hipertensión Renovascular , Proteína Quinasa 3 Activada por Mitógenos , Núcleo Hipotalámico Paraventricular , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 1 , Animales , Núcleo Hipotalámico Paraventricular/metabolismo , Núcleo Hipotalámico Paraventricular/enzimología , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/fisiopatología , Hipertensión Renovascular/fisiopatología , Hipertensión Renovascular/enzimología , Hipertensión Renovascular/metabolismo , Hipertensión Renovascular/tratamiento farmacológico , Masculino , Proteínas Quinasas Activadas por AMP/metabolismo , Fosforilación , Receptor de Angiotensina Tipo 1/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Factor de Transcripción ReIA/metabolismo , Ribonucleótidos/farmacología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Sistema Nervioso Simpático/fisiopatología , Sistema Nervioso Simpático/efectos de los fármacos , Sistema Nervioso Simpático/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , FN-kappa B/metabolismo , Transducción de Señal , Antihipertensivos/farmacología , RatasRESUMEN
The Renin-Angiotensin-Aldosterone System (RAAS) has been implicated in systemic and neurogenic hypertension. The infusion of RAAS inhibitors blunted arterial pressure and efficacy of use-dependent synaptic transmission in sympathetic ganglia. The current investigation aims to elucidate the impact of RAAS-mediated receptors on left ventricular cardiomyocytes and the role of the sarcolemma-bound carrier system in the heart of the hypertensive transgene model. A significant increase in mRNA and the protein expression for angiotensin II (AngII) receptor subtype-1 (AT1R) was observed in (mREN2)27 transgenic compared to the normotensive rodents. Concurrently, there was an upregulation in AT1R and a downregulation in the MAS1 proto-oncogene protein receptor as well as the AngII subtype-2 receptor in hypertensive rodents. There were modifications in the expressions of sarcolemma Na+-K+-ATPase, Na+-Ca2+ exchanger, and Sarcoendoplasmic Reticulum Calcium ATPase in the transgenic hypertensive model. These observations suggest chronic RAAS activation led to a shift in receptor balance favoring augmented cardiac contractility and disruption in calcium handling through modifications of membrane-bound carrier proteins and blood pressure. The study provides insight into mechanisms underlying RAAS-mediated cardiac dysfunction and highlights the potential value of targeting the protective arm of AngII in hypertension.
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Ventrículos Cardíacos , Hipertensión , Sistema Renina-Angiotensina , Animales , Hipertensión/metabolismo , Ventrículos Cardíacos/metabolismo , Miocitos Cardíacos/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/genética , Ratas , Proto-Oncogenes Mas , Presión Sanguínea , Masculino , Ratones , Receptor de Angiotensina Tipo 2/metabolismo , Receptor de Angiotensina Tipo 2/genética , Sarcolema/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , Intercambiador de Sodio-Calcio/metabolismo , Intercambiador de Sodio-Calcio/genética , Ratones TransgénicosRESUMEN
BACKGROUND: Diabetes mellitus is generally accompanied by dyslipidaemia, but inconsistent relationships between lipid profiles and diabetes are noted. Moreover, genetic variations in insertion/deletion (I/D) polymorphisms at angiotensin-converting enzyme gene (ACE) and T/C polymorphisms in the angiotensin type 1 receptor gene (AGTR1) are related to diabetes and lipid levels, but the associations are controversial. Thus, the current research aimed to explore the effects of ACE I/D, AGTR1 rs5182 and diabetes mellitus on serum lipid profiles in 385 Chinese participants with an average age of 75.01 years. METHODS: The ACE I/D variant was identified using the polymerase chain reaction (PCR) method, whereas the AGTR1 rs5182 polymorphism was identified using the PCR-based restriction fragment length polymorphism (PCR-RFLP) method and verified with DNA sequencing. Total cholesterol (TC), triglyceride (TG), apolipoprotein A (ApoA), apolipoprotein B (ApoB), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were measured using routine methods, and the lipid ratios were calculated. RESULTS: ACE I/D, but not AGTR1 rs5182, was a predictor of TG/HDL-C for the whole study population. Both ACE I/D and AGTR1 rs5182 were predictors of HDL-C and LDL-C levels in females but not in males. Moreover, in females, diabetes mellitus and ACE I/D were identified as predictors of TG and TG/HDL-C, whereas AGTR1 rs5182 and diabetes mellitus were predictors of TG/HDL-C. Moreover, diabetes mellitus and the combination of ACE I/D and AGTR1 rs5182 variations were predictors of TG and TG/HDL-C exclusively in females. CONCLUSIONS: The results demonstrated the potential for gender-dependent interactions of ACE I/D, AGTR1 rs5182, and diabetes on lipid profiles. These findings may serve as an additional explanation for the inconsistent changes of blood lipids in individuals with diabetes mellitus, thereby offering a novel perspective for the clinical management of blood lipid levels in diabetic patients.
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Peptidil-Dipeptidasa A , Receptor de Angiotensina Tipo 1 , Humanos , Masculino , Femenino , Anciano , Receptor de Angiotensina Tipo 1/genética , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/sangre , Polimorfismo de Nucleótido Simple , Lípidos/sangre , Lípidos/genética , Pueblo Asiatico/genética , Triglicéridos/sangre , Anciano de 80 o más Años , HDL-Colesterol/sangre , HDL-Colesterol/genética , Diabetes Mellitus/genética , Diabetes Mellitus/sangre , Mutación INDEL , LDL-Colesterol/sangre , LDL-Colesterol/genética , Estudios de Asociación Genética , China/epidemiología , Predisposición Genética a la Enfermedad , Pueblos del Este de AsiaRESUMEN
In this study, we synthesized a series of seven benzimidazole derivatives incorporating the structural acidic framework of angiotensin II (Ang II) type 1 receptor (AT1R) antagonists (ARA-II) employing a three-step reaction sequence. The chemical structures were confirmed by 1H NMR, 13C NMR and mass spectral data. Through biosimulation, compounds 1-7 were identified as computational safe hits, thus, best candidates underwent ex vivo testing against two distinct mechanisms implicated in hypertension: antagonism of the Ang II type 1 receptor and the blockade of calcium channel. Molecular docking studies helped to understand at the molecular level the dual vasorelaxant effects with the recognition sites of the AT1R and the L-type calcium channel. In an in vivo spontaneously hypertensive rat model (SHR), intraperitoneally administration of compound 1 at 20 mg/kg resulted in a 25 % reduction in systolic blood pressure, demonstrating both ex vivo vasorelaxant action and in vivo antihypertensive multitarget efficacy. ©2024 Elsevier.