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1.
Pharmacol Res Perspect ; 11(1): e01053, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36639940

RESUMO

Angiotensin II analogue and ß-arrestin biased agonist TRV027 (Sarcosine1 , d-Alanine8 -Angiotensin (Ang) II; SD Ang II), developed by Trevena, Inc. in the early 2010s, brought hopes of a novel treatment for cardiovascular diseases, due to its ability to simultaneously cause signaling through the ß-arrestin signaling pathway, while antagonizing the pathophysiological effects of Ang II mediated by the AT1 receptor G protein signaling cascades. However, a phase II clinical trial of this agent revealed no significant benefit compared to placebo treatment. Using 125 I-Sarcosine1 , Isoleucine8 -Ang II (125 I-SI Ang II) radioligand receptor competition binding assays, we assessed the relative affinity of TRV027 compared to SI Ang II for liver AT1 receptors. We also compared radioiodinated TRV027 (125 I-SD Ang II) binding affinity for liver AT1 receptors with 125 I-SI Ang II. We found that despite its anticipated gain in metabolic stability, TRV027 and 125 I-SD Ang II had reduced affinity for the AT1 receptor compared with SI Ang II and 125 I-SI Ang II. Additionally, male-female comparisons showed that females have a higher AT1 receptor density, potentially attributed to tissue-dependent estrogen and progesterone effects. Peptide drugs have become more popular over the years due to their increased bioavailability, fast onset of action, high specificity, and low toxicity. Even though Trevena®'s biased agonist peptide TRV027 offered greater stability and potency compared to earlier AT1 R biased agonists, it failed its phase II clinical trial in 2016. Further refinements to AT1 R biased agonist peptides to improve affinity, as seen with SI Ang II, with better stability and bioavailability, has the potential to achieve the anticipated biased agonism.


Assuntos
Angiotensina II , Fígado , Receptor Tipo 1 de Angiotensina , Sarcosina , Animais , Feminino , Masculino , Ratos , Alanina/metabolismo , Angiotensina II/farmacologia , beta-Arrestinas/metabolismo , Isoleucina/metabolismo , Fígado/metabolismo , Sarcosina/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-36704758

RESUMO

Objective: We reported that rats infused with angiotensin II (Ang II) are not only a model of hypertension but also of augmented 24 h blood pressure variability (BPV). In this study, we examined the mechanisms for Ang II-induced BPV, focusing on BP, heart rate (HR), baroreceptor reflex sensitivity (BRS), and medial area of the aortic arch. Methods: Nine-week-old male Wistar rats were infused with subcutaneous 5.2 µg/kg/h Ang II with or without oral administration with 30 mg/kg/day azelnidipine for 14 days. BP and HR were recorded every 15 min under an unrestrained condition by a radiotelemetry system, while BPV was evaluated by standard deviation of BP. BRS was quantified by a sequence analysis, and medial thickness of the aortic arch was measured by microscopic examination. Results: BPV increased at days 7 and 14 following continuous infusion of Ang II. Before the infusion, a positive correlation was found between BP and HR, but it became negative at day 7 and then weakened or disappeared at day 14. BRS was slightly impaired at day 7 and significantly lowered at day 14, a phenomenon accompanied by thickened medial area of the aortic arch in Ang II-infused rats. Those Ang II-induced alterations were all significantly attenuated by azelnidipine. Conclusions: The present findings suggest sequential changes in the mechanisms behind augmented BPV in rats continuously infused with Ang II over 14 days.


Assuntos
Angiotensina II , Hipertensão , Ratos , Masculino , Animais , Pressão Sanguínea , Angiotensina II/farmacologia , Ratos Wistar , Hipertensão/tratamento farmacológico
3.
Sci Rep ; 13(1): 519, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627369

RESUMO

The study aim was to determine if suppressed activation of angiotensin II type 1 receptor (AT1) prevents severe muscle atrophy after denervation. The sciatic nerves in right and left inferior limbs were cut in AT1a knockout homo (AT1a-/-) male mice and wild-type (AT1a+/+) male mice. Muscle weight and cross-sectional areas of type IIb muscle fibers in gastrocnemius muscle decreased at 7 and 21 days postdenervation in both AT1a-/- mice and AT1a+/+ mice, and the reduction was significantly attenuated in the denervated muscles of AT1a-/- mice compared to the AT1a+/+ mice. Gene expressions in the protein degradation system [two E3 ubiquitin ligases (muscle RING-finger protein-1 and Atrogin-1)] upregulated at 7 days postdenervation in all denervated mice were significantly lower in AT1a-/- mice than in AT1a+/+ mice. Activations of nuclear factor κB and Forkhead box subgroup O1, and protein expression of monocyte chemoattractant protein-1 were significantly suppressed in the AT1a-/- mice compared with those in the AT1a+/+ mice. In addition, suppressed apoptosis, lower infiltration of M1 macrophages, and higher infiltration of M2 macrophages were significantly observed at 21 days postdenervation in the AT1a-/- mice compared with those in the AT1a+/+ mice. In conclusion, the AT1 receptor deficiency retarded muscle atrophy after denervation.


Assuntos
Denervação , Atrofia Muscular , Receptor Tipo 1 de Angiotensina , Animais , Masculino , Camundongos , Angiotensina II/farmacologia , Camundongos Knockout , Músculo Esquelético/metabolismo , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores de Angiotensina , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
4.
Physiol Rep ; 11(2): e15581, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36708509

RESUMO

Macrophages play crucial roles in abdominal aortic aneurysm (AAA) formation through the inflammatory response and extracellular matrix degradation; therefore, regulating macrophages may suppress AAA formation. Interleukin-38 (IL-38) is a member of the IL-1 family, which binds to IL-36 receptor (IL1RL2) and has an anti-inflammation effect. Because macrophages express IL1RL2, we hypothesized that IL-38 suppresses AAA formation by controlling macrophages. We assessed a C57BL6/J mouse angiotensin II-induced AAA model with or without IL-38 treatment. RAW 264.7 cells were cultured with tumor necrosis factor-α and treated with or without IL-38. Because p38 has important roles in inflammation, we assessed p38 phosphorylation in vitro and in vivo. To clarify whether the IL-38 effect depends on the p38 pathway, we used SB203580 to inhibit p38 phosphorylation. IL1RL2+ macrophage accumulation along with matrix metalloproteinase (MMP)-2 and -9 expression was observed in mouse AAA. IL-38 reduced the incidence of AAA formation along with reduced M1 macrophage accumulation and MMP-2 and -9 expression in the AAA wall. Macrophage activities including inducible nitric oxide, MMP-2, and MMP-9 production and spindle-shaped changes were significantly suppressed by IL-38. Furthermore, we revealed that inhibition of p38 phosphorylation diminished the effects of IL-38 on regulating macrophages to reduce AAA incidence, indicating the protective effects of IL-38 depend on the p38 pathway. IL-38 plays protective roles against AAA formation through regulation of macrophage accumulation in the aortic wall and modulating the inflammatory phenotype. Using IL-38 may be a novel therapy for AAA patients.


Assuntos
Aneurisma da Aorta Abdominal , Metaloproteinase 2 da Matriz , Animais , Camundongos , Angiotensina II/farmacologia , Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/prevenção & controle , Modelos Animais de Doenças , Interleucinas/metabolismo , Macrófagos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Cell Mol Life Sci ; 80(2): 38, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629913

RESUMO

BACKGROUND: Vascular endothelial dysfunction is regarded as an early event of hypertension. Galectin-3 (Gal-3) is known to participate in various pathological processes. Whilst previous studies showed that inhibition of Gal-3 effectively ameliorates angiotensin II (Ang II)-induced atherosclerosis or hypertension, it remains unclear whether Ang II regulates Gal-3 expression and actions in vascular endothelium. METHODS: Using techniques of molecular biology and myograph, we investigated Ang II-mediated changes in Gal-3 expression and activity in thoracic aortas and mesenteric arteries from wild-type and Gal-3 gene deleted (Gal-3-/-) mice and cultured endothelial cells. RESULTS: The serum level of Gal-3 was significantly higher in hypertensive patients or in mice with chronic Ang II-infusion. Ang II infusion to wild-type mice enhanced Gal-3 expression in the aortic and mesenteric arteries, elevated systolic blood pressure and impaired endothelium-dependent relaxation of the thoracic aortas and mesenteric arteries, changes that were abolished in Gal-3-/- mice. In human umbilical vein endothelial cells, Ang II significantly upregulated Gal-3 expression by promoting nuclear localization of Yes-associated protein (YAP) and its interaction with transcription factor Tead1 with enhanced YAP/Tead1 binding to Gal-3 gene promoter region. Furthermore, Gal-3 deletion augmented the bioavailability of nitric oxide, suppressed oxidative stress, and alleviated inflammation in the thoracic aorta of Ang II-infused mice or endothelial cells exposed to Ang II. CONCLUSIONS: Our results demonstrate for the first time that Ang II upregulates Gal-3 expression via increment in YAP nuclear localization in vascular endothelium, and that Gal-3 mediates endothelial dysfunction contributing to the development of hypertension.


Assuntos
Angiotensina II , Hipertensão , Camundongos , Humanos , Animais , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Hipertensão/metabolismo , Transdução de Sinais , Células Endoteliais da Veia Umbilical Humana/metabolismo , Endotélio Vascular/metabolismo , Pressão Sanguínea
6.
Prog Mol Biol Transl Sci ; 194: 49-65, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36631200

RESUMO

The renin angiotensin system (RAS) plays a major role in blood pressure regulation and electrolyte homeostasis and is mainly composed by two axes mediating opposite effects. The pressor axis, constituted by angiotensin (Ang) II and the Ang II type 1 receptor (AT1R), exerts vasoconstrictor, proliferative, hypertensive, oxidative and pro-inflammatory actions, while the depressor/protective axis, represented by Ang-(1-7), its Mas receptor (MasR) and the Ang II type 2 receptor (AT2R), opposes the actions elicited by the pressor arm. The MasR belongs to the G protein-coupled receptor (GPCR) family. To avoid receptor overstimulation, GPCRs undergo internalization and trafficking into the cell after being stimulated. Then, the receptor may induce other signaling cascades or it may even interact with other receptors, generating distinct biological responses. Thus, control of a GPCR regarding space and time affects the specificity of the signals transduced by the receptor and the ultimate cellular response. The present chapter is focused on the signaling and trafficking pathways of MasR under physiological conditions and its participation in the pathogenesis of numerous brain diseases.


Assuntos
Proto-Oncogene Mas , Sistema Renina-Angiotensina , Humanos , Sistema Renina-Angiotensina/fisiologia , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Pressão Sanguínea/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Endocitose
7.
Brain Behav Immun ; 108: 255-268, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36535607

RESUMO

The metabolic syndrome has been associated to chronic peripheral inflammation and related with neuroinflammation and neurodegeneration, including Parkinson's disease. However, the responsible mechanisms are unclear. Previous studies have involved the brain renin-angiotensin system in progression of Parkinson's disease and the angiotensin receptor type 1 (AT1) has been recently revealed as a major marker of dopaminergic vulnerability in humans. Dysregulation of tissue renin-angiotensin system is a key common mechanism for all major components of metabolic syndrome. Circulating AT1 agonistic autoantibodies have been observed in several inflammation-related peripheral processes, and activation of AT1 receptors of endothelial cells, dopaminergic neurons and glial cells have been observed to disrupt endothelial blood -brain barrier and induce neurodegeneration, respectively. Using a rat model, we observed that metabolic syndrome induces overactivity of nigral pro-inflammatory renin-angiotensin system axis, leading to increase in oxidative stress and neuroinflammation and enhancing dopaminergic neurodegeneration, which was inhibited by treatment with AT1 receptor blockers (ARBs). In rats, metabolic syndrome induced the increase in circulating levels of LIGHT and other major pro-inflammatory cytokines, and 27-hydroxycholesterol. Furthermore, the rats showed a significant increase in serum levels of proinflammatory AT1 and angiotensin converting enzyme 2 (ACE2) autoantibodies, which correlated with levels of several metabolic syndrome parameters. We also found AT1 and ACE2 autoantibodies in the CSF of these rats. Effects of circulating autoantibodies were confirmed by chronic infusion of AT1 autoantibodies, which induced blood-brain barrier disruption, an increase in the pro-inflammatory renin-angiotensin system activity in the substantia nigra and a significant enhancement in dopaminergic neuron death in two different rat models of Parkinson's disease. Observations in the rat models, were analyzed in a cohort of parkinsonian and non-parkinsonian patients with or without metabolic syndrome. Non-parkinsonian patients with metabolic syndrome showed significantly higher levels of AT1 autoantibodies than non-parkinsonian patients without metabolic syndrome. However, there was no significant difference between parkinsonian patients with metabolic syndrome or without metabolic syndrome, which showed higher levels of AT1 autoantibodies than non-parkinsonian controls. This is consistent with our recent studies, showing significant increase of AT1 and ACE2 autoantibodies in parkinsonian patients, which was related to dopaminergic degeneration and neuroinflammation. Altogether may lead to a vicious circle enhancing the progression of the disease that may be inhibited by strategies against production of these autoantibodies or AT1 receptor blockers (ARBs).


Assuntos
Síndrome Metabólica , Doença de Parkinson , Animais , Humanos , Ratos , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Enzima de Conversão de Angiotensina 2/metabolismo , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Autoanticorpos/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Células Endoteliais/metabolismo , Inflamação/metabolismo , Síndrome Metabólica/metabolismo , Doenças Neuroinflamatórias , Doença de Parkinson/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo
8.
J Mol Graph Model ; 118: 108365, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36335829

RESUMO

The structural features that contribute to the efficacy of biased agonists targeting G protein-coupled receptors (GPCRs) towards G proteins or ß-arrestin (ß-arr) signaling pathways is nebulous, although such knowledge is critical in designing biased ligands. The dynamics of the agonist-GPCR complex is one of the critical factors in determining agonist bias. Angiotensin II type I receptor (AT1R) is an ideal model system to study the molecular basis of bias since it has multiple ß-arr2 and Gq protein biased agonists as well as experimentally solved three dimensional structures. Using Molecular Dynamics (MD) simulations for the Angiotensin II type I receptor (AT1R) bound to ten different agonists, we infer that the agonist bound receptor samples conformations with different relative weights, from both the inactive and active state ensembles of the receptor. This concept is perhaps extensible to other class A GPCRs. Such a weighted mixed ensemble recapitulates the inter-residue distance distributions measured for different agonists bound AT1R using DEER experiments. The ratio of the calculated relative strength of the allosteric communication to ß-arr2 vs Gq coupling sites scale similarly to the experimentally measured bias factors. Analysis of the inter-residue distance distributions of the activation microswitches involved in class A GPCR activation suggests that ß-arr2 biased agonists turn on different combination of microswitches with different relative strengths of activation. We put forth a model that activation microswitches behave like rheostats that tune the relative efficacy of the biased agonists toward the two signaling pathways. Finally, based on our data we propose that the agonist specific residue contacts in the binding site elicit a combinatorial response in the microswitches that in turn differentially modulate the receptor conformation ensembles resulting in differences in coupling to Gq and ß-arrestin.


Assuntos
Angiotensina II , Receptor Tipo 1 de Angiotensina , Receptor Tipo 1 de Angiotensina/agonistas , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina II/química , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , beta-Arrestinas/metabolismo , Ligantes , Conformação Proteica
9.
Brain Res ; 1802: 148218, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36572371

RESUMO

The hypothalamic paraventricular nucleus (PVN) is an important brain region involved in control of the cardiovascular system. Direct injection of angiotensin II (AngII) into the PVN produces a short or long pressor response. This study was performed in anesthetized rats to find whether the parvocellular part of the paraventricular nucleus (PVNp) affects the baroreflex. And if so, what is the effect of AngII injected into the PVNp on the baroreflex? Drugs were microinjected into the PVNp while blood pressure and heart rate were recorded continuously. We found that microinjection of AT1 and AT2 receptor antagonists into the PVNp region did not affect the baseline mean arterial pressure (MAP) and heart rate (HR) indicating that under normal conditions AngII may not provide tonic activity, at least in anaesthetized animals. Bilateral microinjections of a synaptic blocker (CoCl2) into the PVNp attenuated the baroreflex gains in responses to loading and unloading of baroreceptors, indicating that PVNp is involved in the baroreflex rate component. Microinjection of AngII into the PVNp increased MAP and HR. However, AngII slightly attenuated the baroreflex rate component using its two receptors AT1 and AT2. Collectively, these findings suggest that the PVNp as a whole is involved in the baroreflex. But AngII attenuates the heart rate response of the baroreflex through AT1 and AT2 receptors.


Assuntos
Angiotensina II , Núcleo Hipotalâmico Paraventricular , Ratos , Animais , Angiotensina II/farmacologia , Ratos Wistar , Barorreflexo , Pressão Sanguínea , Frequência Cardíaca , Microinjeções
10.
Eur J Pharmacol ; 940: 175475, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36563952

RESUMO

Vascular endothelial dysfunction plays a central role in the most dreadful human diseases, including stroke, tumor metastasis, and the coronavirus disease 2019 (COVID-19). Strong evidence suggests that angiotensin II (Ang II)-induced mitochondrial dysfunction is essential for endothelial dysfunction pathogenesis. However, the precise molecular mechanisms remain obscure. Here, polymerase-interacting protein 2 (Poldip 2) was found in the endothelial mitochondrial matrix and no effects on Poldip 2 and NADPH oxidase 4 (NOX 4) expression treated by Ang II. Interestingly, we first found that Ang II-induced NOX 4 binds with Poldip 2 was dependent on cyclophilin D (CypD). CypD knockdown (KD) significantly inhibited the binding of NOX 4 to Poldip 2, and mitochondrial ROS generation in human umbilical vein endothelial cells (HUVECs). Similar results were also found in cyclosporin A (CsA) treated HUVECs. Our previous study suggested a crosstalk between extracellular regulated protein kinase (ERK) phosphorylation and CypD expression, and gallic acid (GA) inhibited mitochondrial dysfunction in neurons depending on regulating the ERK-CypD axis. Here, we confirmed that GA inhibited Ang II-induced NOX 4 activation and mitochondrial dysfunction via ERK/CypD/NOX 4/Poldip 2 pathway, which provide novel mechanistic insight into CypD act as a key regulator of the NOX 4/Poldip 2 axis in Ang II-induced endothelial mitochondrial dysfunction and GA might be beneficial in the treatment of wide variety of diseases, such as COVID-19, which is worthy further research.


Assuntos
COVID-19 , Doenças Vasculares , Humanos , NADPH Oxidase 4/metabolismo , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ciclofilina D/metabolismo , Ciclofilina D/farmacologia , NADPH Oxidases/metabolismo , Estresse Oxidativo , Ácido Gálico/farmacologia , COVID-19/metabolismo , Mitocôndrias , Células Endoteliais da Veia Umbilical Humana
11.
Biochem Biophys Res Commun ; 642: 11-20, 2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36543019

RESUMO

Endothelial progenitor cells (EPCs) are crucial for the maintenance of vascular homeostasis. The dysfunction of EPCs contributes to the endothelial damage in hypertension. Andrographolide (AGP) is a traditional Chinese patent medicine that has been reported to have protective effects on cardiovascular system. However, the effect of AGP on the function of EPCs in hypertension remains unknown. In this study, we aimed to elucidate the effect of AGP on EPCs and the underlying mechanisms. In vivo, the blood pressure and endothelial function (indicated by endothelial dependent vasodilation) of AGP-fed angiotensin II (Ang II)-infused hypertensive mice were examined. In vitro, the function of EPCs isolated from bone marrow were evaluated by tube formation, migration, and adhesion assay. Additionally, a silent information regulator 1 (SIRT1) inhibitor/agonist and a small interfering RNA (si-RNA) targeting SIRT1 were used to determine the pathway involved. The results showed that AGP not only reduced blood pressure, improved endothelial function in hypertensive mice but also restored the dysfunction of EPCs of hypertension in vitro. Mechanistically, AGP up-regulated SIRT1 expression, decreased the Bax/Bcl-2 ratio and the expression level of Cleaved caspase-3, thus inhibiting the apoptosis of Ang II induced EPCs. However, the beneficial effects of AGP on EPCs disappeared after the inhibition or the knockdown of SIRT1. To summarize, this study demonstrates for the first time that AGP improves the dysfunction of EPCs through SIRT1-mediated anti-apoptotic effects. Our findings might provide a novel therapeutic strategy for treating vascular damage in hypertension.


Assuntos
Células Progenitoras Endoteliais , Hipertensão , Camundongos , Animais , Células Progenitoras Endoteliais/metabolismo , Angiotensina II/farmacologia , Sirtuína 1/metabolismo , Células Cultivadas , Hipertensão/metabolismo
12.
Anal Chem ; 95(2): 730-738, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36574961

RESUMO

The mechanisms by which angiotensin II type 1 receptor is distributed and the diffusional pattern in the plasma membrane (PM) remain unclear, despite their crucial role in cardiovascular homeostasis. In this work, we obtained quantitative information of angiotensin II type 1 receptor (AT1R) lateral dynamics as well as changes in the diffusion properties after stimulation with ligands in living cells using photoactivated localization microscopy (PALM) combined with image spatial-temporal correlation analysis. To study the organization of the receptor at the nanoscale, expansion microscopy (ExM) combined with PALM was performed. This study revealed that AT1R lateral diffusion increased after binding to angiotensin II (Ang II) and the receptor diffusion was transiently confined in the PM. In addition, ExM revealed that AT1R formed nanoclusters at the PM and the cluster size significantly decreased after Ang II treatment. Taking these results together suggest that Ang II binding and activation cause reorganization and changes in the dynamics of AT1R at the PM.


Assuntos
Angiotensina II , Receptor Tipo 1 de Angiotensina , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Microscopia , Membrana Celular/metabolismo
13.
Hypertension ; 80(1): 57-69, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36377602

RESUMO

BACKGROUND: Leukocyte adhesion to endothelium is an early inflammatory response and is mainly controlled by the ß2-integrins. However, the role of integrin CD11b/CD18 in the pathogenesis of hypertension and vascular dysfunction is unclear. METHODS: Hypertension was established by angiotensin II (490 ng/kg·per min) or deoxycorticosterone acetate salt. Hypertensive responses were studied in CD11b-deficient (CD11b-/-) mice, bone marrow transplanted and wild-type (WT) mice that were administered anti-CD11b neutralizing antibody or agonist leukadherin-1. Blood pressure was monitored with tail-cuff method and radiotelemetry. Blood and vascular inflammatory cells were assessed by flow cytometry. Aortic remodeling and function were examined using histology and aortic ring analysis. Cell adhesion and migration were evaluated in vitro. The relationship between circulating CD11b+ immune cells and hypertension was analyzed in patients with hypertension. RESULTS: We found that CD11b and CD18 expression as well as the CD45+CD11b+CD18+ myeloid cells were highly increased in the aorta of angiotensin II-infused mice. Ablation or pharmacological inhibition of CD11b in mice significantly alleviated hypertension, aortic remodeling, superoxide generation, vascular dysfunction, and the infiltration of CD11b+ macrophages through reducing macrophage adhesion and migration. These effects were confirmed in WT mice reconstituted with CD11b-deficient bone marrow cells. Conversely, angiotensin II-induced hypertensive response was exacerbated by CD11b agonist leukadherin-1. Notably, circulating CD45+CD11b+CD18+ myeloid cells and the ligand levels in hypertensive patients were significantly higher than in normotensive controls. CONCLUSIONS: We demonstrated a critical significance of CD11b+ myeloid cells in hypertension and vascular dysfunction. Targeting CD11b may represent a novel therapeutic option for hypertension.


Assuntos
Hipertensão , Integrinas , Camundongos , Animais , Angiotensina II/farmacologia , Macrófagos
14.
Zhongguo Zhong Yao Za Zhi ; 47(21): 5900-5907, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-36472009

RESUMO

This study was designed to determine the inhibitory effect of astragaloside Ⅳ(AS-Ⅳ), a principal bioactive component extracted from the Chinese medicinal Astragali Radix, on the inflammatory response of vascular endothelial cells induced by angiotensin Ⅱ(Ang Ⅱ), the most major pathogenic factor for cardiovascular diseases, and to clarify the role of calcium(Ca~(2+))/phosphatidylinosi-tol-3-kinase(PI3K)/protein kinase B(Akt)/endothelial nitric oxide synthase(eNOS)/nitric oxide(NO) pathway in the process. To be specific, human umbilical vein endothelial cells(HUVECs) were cultured in the presence of AS-Ⅳ with or without the specific inhibitor of NO synthase(NG-monomethyl-L-arginine, L-NMMA), inhibitor of PI3K/Akt signaling pathway(LY294002), or Ca~(2+)-chelating agent(ethylene glycol tetraacetic acid, EGTA) prior to Ang Ⅱ stimulation. The inhibitory effect of AS-Ⅳ on Ang Ⅱ-induced inflammatory response and the involved mechanism was determined with enzyme-linked immunosorbent assay(ELISA), cell-based ELISA assay, Western blot, and monocyte adhesion assay which determined the fluorescently labeled human monocytic cell line(THP-1) adhered to Ang Ⅱ-stimulated endothelial cells. AS-Ⅳ increased the production of NO by HUVECs in a dose-and time-dependent manner(P<0.05) and raised the level of phosphorylated eNOS(P<0.05). The above AS-Ⅳ-induced changes were abolished by pretreatment with L-NMMA, LY294002, or EGTA. Compared with the control group, Ang Ⅱ obviously enhanced the production and release of cytokines(tumor necrosis factor-α, interleukin-6), chemokines(monocyte chemoattractant protein-1) and adhesion molecules(intercellular adhesion molecule-1, vascular cellular adhesion molecule-1), and the number of monocytes adhered to HUVECs(P<0.05), which were accompanied by the enhanced levels of phosphorylated inhibitor of nuclear factor-κBα protein and activities of nuclear factor-κB(NF-κB)(P<0.05). This study also demonstrated that Ang Ⅱ-induced inflammatory response was inhibited by pretreatment with AS-Ⅳ(P<0.05). In addition, the inhibitory effect of AS-Ⅳ was abrogated by pretreatment with L-NMMA, LY294002, or EGTA(P<0.05). This study provides a direct link between AS-Ⅳ and Ca~(2+)/PI3K/Akt/eNOS/NO pathway in AS-Ⅳ-mediated anti-inflammatory actions in endothelial cells exposed to Ang Ⅱ. The results indicate that AS-Ⅳ attenuates endothelial cell-mediated inflammatory response induced by Ang Ⅱ via the activation of Ca~(2+)/PI3K/Akt/eNOS/NO signaling pathway.


Assuntos
Angiotensina II , Proteínas Proto-Oncogênicas c-akt , Humanos , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , ômega-N-Metilarginina/metabolismo , ômega-N-Metilarginina/farmacologia , Ácido Egtázico/metabolismo , Ácido Egtázico/farmacologia , Células Endoteliais da Veia Umbilical Humana , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Células Cultivadas
15.
Front Biosci (Landmark Ed) ; 27(11): 299, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36472099

RESUMO

BACKGROUND: To investigate the effect and potential molecular mechanisms of Dipsacoside B (DB), an herb monomer extracted from Dipsacusasper or Lonicera macranthoides, on the migration and proliferation of vascular smooth muscle cells (VSMCs) and balloon-induced neointimal formation. METHODS: In vivo, rat abdominal aorta balloon injury model was utilized to investigate the effect of DB on the neointimal formation. In vitro, cultured VSMCs were used to investigate the effect of DB on Angiotensin-II (Ang-II)-induced migration and proliferation of VSMCs. Western blot and immunofluorescence were used to measure PTEN expression. RESULTS: As compared to vehicle control balloon-injury group, DB treatment significantly inhibited the neointimal formation together up-regulated the expression of phosphatase and tension homolog deleted on chromosome 10 (PTEN). Cell proliferations (MTT and Edu incorporation) assays and wound migration measurement further revealed that treatment with DB significantly blunted Ang-II-induced proliferation and migration potential of VSMCs. Western blot analysis exhibited that DB upregulated the expression of PTEN in vivo and in vitro. CONCLUSIONS: DB treatment suppresses the proliferation and migration of VSMCs and reduces neointimal formation by the mechanisms involving regulating the phenotype switch of VSMCs via upregulating PTEN expression.


Assuntos
Músculo Liso Vascular , Miócitos de Músculo Liso , Ratos , Animais , Movimento Celular , Neointima/metabolismo , Proliferação de Células , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Células Cultivadas , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo
16.
Physiol Rep ; 10(24): e15551, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36564179

RESUMO

Experiments were designed to test the hypothesis that median preoptic (MnPO) neurons are necessary for the full hypertensive response to chronic angiotensin II (AngII) in rats consuming a high salt diet. The MnPO is implicated in many of the physiologic actions of AngII, primarily acting as a downstream nucleus to AngII binding at circumventricular organs such as the organum vasculosum of the lamina terminalis (OVLT). We have previously shown a prominent effect of lesion of the OVLT on the chronic hypertensive effects of AngII in rats consuming high salt. Additionally, we have shown that lesion of the MnPO attenuated the hypertensive response to chronic intravenous infusion of AngII in rats. However, whether MnPO neurons or fibers of passage contribute to this response is not clear. Male Sprague Dawley rats were randomly assigned to either sham (SHAM; n = 8) or ibotenic acid lesion of the MnPO (MnPOx; n = 6). In the MnPOx group, 200 nl of ibotenic acid in phosphate buffer saline (5 µg/µl) was injected into each of 3 predetermined coordinates targeted at the entire MnPO. After a week of recovery, rats were instrumented with radiotelemetric pressure transducers, provided 2.0% NaCl diet and distilled water ad libitum and given another week to recover. After 3 days of baseline measurements, osmotic minipumps were implanted subcutaneously in all rats for administration of AngII at a rate of 150 ng/kg/min. Blood pressure measurements were made for 14 days after minipump implantation. By day 7 of AngII treatment, blood pressure responses appeared to plateau in both groups while the hypertensive response was markedly attenuated in MnPOx rats (MnPOx, 122 ± 6 mmHg; SHAM, 143 ± 8 mmHg). These results support the hypothesis that neurons of the MnPO are involved in the central pathway mediating the chronic hypertensive effects of AngII in rats consuming a high salt diet.


Assuntos
Angiotensina II , Hipertensão , Animais , Masculino , Ratos , Angiotensina II/farmacologia , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Ácido Ibotênico/farmacologia , Neurônios/metabolismo , Área Pré-Óptica/metabolismo , Ratos Sprague-Dawley , Cloreto de Sódio na Dieta/farmacologia
17.
Int J Mol Sci ; 23(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36555708

RESUMO

Notch3 plays an important role in the differentiation and development of vascular smooth muscle cells. Mice lacking Notch3 show deficient renal autoregulation. The aim of the study was to investigate the mechanisms involved in the Notch3-mediated control of renal vascular response. To this end, renal resistance vessels (afferent arterioles) were isolated from Notch3-/- and wild-type littermates (WT) and stimulated with angiotensin II (ANG II). Contractions and intracellular Ca2+ concentrations were blunted in Notch3-/- vessels. ANG II responses in precapillary muscle arterioles were similar between the WT and Notch3-/- mice, suggesting a focal action of Notch3 in renal vasculature. Abolishing stored Ca2+ with thapsigargin reduced Ca2+ responses in the renal vessels of the two strains, signifying intact intracellular Ca2+ mobilization in Notch3-/-. EGTA (Ca2+ chelating agent), nifedipine (L-type channel-blocker), or mibefradil (T-type channel-blocker) strongly reduced contraction and Ca2+ responses in WT mice but had no effect in Notch3-/- mice, indicating defective Ca2+ entry. Notch3-/- vessels responded normally to KCl-induced depolarization, which activates L-type channels directly. Differential transcriptomic analysis showed a major down-regulation of Cacna1h gene expression, coding for the α1H subunit of the T-type Ca2+ channel, in Notch3-/- vessels. In conclusion, renal resistance vessels from Notch3-/- mice display altered vascular reactivity to ANG II due to deficient Ca2+-entry. Consequently, Notch3 is essential for proper excitation-contraction coupling and vascular-tone regulation in the kidney.


Assuntos
Rim , Nifedipino , Receptor Notch3 , Animais , Camundongos , Angiotensina II/farmacologia , Arteríolas/metabolismo , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Rim/metabolismo , Mibefradil/metabolismo , Nifedipino/farmacologia , Resistência Vascular , Receptor Notch3/genética , Deleção de Genes , Camundongos Knockout
18.
Int J Mol Sci ; 23(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36555515

RESUMO

Cisplatin (CDDP) is an efficient chemotherapeutic drug, whose use is associated with the development of serious undesired toxicities, such as nephrotoxicity. The human organic cation transporter 2 (hOCT2), which is highly expressed in the basolateral membrane domain of renal proximal tubules seems to play an important role in the development of CDDP nephrotoxicity. The role of angiotensin II (AII) signaling by binding to the AII receptor type 1 (AT1R) in the development and/or progression of CDDP nephrotoxicity is debated. Therefore, in this work, the regulation of hOCT2 activity by AII and its role in the development of CDDP cellular toxicity was investigated. To do this, hOCT2 was overexpressed by viral transduction in Madin-Darby Canine Kidney (MDCK) cells which were cultivated on a filter. This approach allows the separation of an apical and a basolateral membrane domain, which are easily accessible for experimentation. In this system, hOCT2 was mainly localized on the basolateral plasma membrane domain of the cells. The transporter was functional since a specific uptake of the fluorescent organic cation 4-(4-(dimethylamino)styryl)-N-methylpyridinium (ASP+) with an affinity (Km) of 35 µM was only detectable by the addition of ASP+ to the basolateral compartment of hOCT2 expressing MDCK (hOCT2-MDCK) cells. Similarly, CDDP toxicity was evident mainly by CDDP addition to the basolateral compartment of hOCT2-MDCK cells cultivated on a filter. The addition of 1 nM AII stimulated hOCT2 function via PKC activation and worsened CDDP cytotoxicity via binding to AT1R. Therefore, the AII signaling pathway may be implicated in the development and/or progression of CDDP nephrotoxicity. This signaling pathway may be a target for protective interventions for example by blocking AT1R in the kidneys. However, it should be further investigated whether these findings obtained in a cell culture system may have translational relevance for the clinical situation. For toxicity experiments, a 100 µM CDDP concentration was used, which is high but allows us to identify clearly toxic effects due to hOCT2. In summary, down-regulation of hOCT2 activity by the inhibition of the AII signaling pathway may protect against CDDP nephrotoxicity.


Assuntos
Angiotensina II , Cisplatino , Humanos , Animais , Cães , Transportador 2 de Cátion Orgânico/genética , Cisplatino/toxicidade , Cisplatino/metabolismo , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Túbulos Renais/metabolismo , Rim/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo
19.
J Adv Res ; 41: 205-218, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36328749

RESUMO

INTRODUCTION: Vascular smooth muscle cell (VSMC) senescence in the vasculature results in vascular aging as well as age-related diseases, while metformin improves the inflamm-aging profile by enhancing autophagy. However, metformin's impact on VSMC senescence is largely undefined. OBJECTIVES: To test the hypothesis that metformin exerts an anti-senescence role by restoring autophagic activity in VSMCs and vascular tissues. METHODS: Animal models established by angiotensin II (Ang II) induction and physiological aging and senescent primary VSMCs from the aortas of elderly patients were treated with metformin. Cellular and vascular senescence were assessed by measuring the amounts of senescence-associated ß-galactosidase and senescence markers, including p21 and p53. Autophagy levels were assessed by autophagy-related protein expression, transmission electron microscope, and autolysosome staining. In order to explore the underlying mechanism of the anti-senescence effects of metformin, 4D label-free quantitative proteomics and bioinformatic analyses were conducted, with subsequent experiments validating these findings. RESULTS: Ang II-dependent senescence was suppressed by metformin in VSMCs and vascular tissues. Metformin also significantly improved arterial stiffness and alleviated structural changes in aged arteries, reduced senescence-associated secretory phenotype (SASP), and improved proliferation and migration of senescent VSMCs. Mechanistically, the proteomic analysis indicated that autophagy might contribute to metformin's anti-senescence effects. Reduced autophagic flux was observed in Ang II-induced cellular and vascular senescence; this reduction was reversed by metformin. Specifically, metformin enhanced the autophagic flux at the autophagosome-lysosome fusion level, whereas blockade of autophagosome-lysosome fusion inhibited the anti-senescence effects of metformin. CONCLUSIONS: Metformin prevents VSMC and vascular senescence by promoting autolysosome formation.


Assuntos
Metformina , Músculo Liso Vascular , Animais , Músculo Liso Vascular/metabolismo , Senescência Celular/fisiologia , Metformina/farmacologia , Metformina/metabolismo , Proteômica , Proteína Supressora de Tumor p53/metabolismo , Estresse Oxidativo , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Autofagia
20.
Eur J Pharmacol ; 937: 175384, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372276

RESUMO

Stimulation of angiotensin II receptor (ATR) with angiotensin II (Ang II) accelerates cardiac fibroblast activation, resulting in upregulation of cytokines and growth factors. Growth factors were strongly upregulated in animal models of myocardial fibrosis and hypertrophy as well as patients with heart failure. Nevertheless, the signal transduction of ATR for upregulation of growth factors in human cardiac fibroblasts contributing to myocyte hypertrophy have not fully understood. Long-term Ang II treatment of human cardiac fibroblasts provokes the synthesis and secretion of connective tissue growth factor (CTGF), transforming growth factor beta1 (TGF-ß1), and vascular endothelial growth factor (VEGF) through the AT1R subtype. Blockade of Gαq, not Gαi or Gα12/13, protein signaling inhibited AT1R-mediated upregulation of CTGF, TGF-ß1, and VEGF. In addition, AT1R overstimulation induced upregulation of growth factors via the TGF-ß-dependent and ERK1/2-dependent pathways. Growth factors secreted from cardiac fibroblasts are necessary for the induction of hypertrophic markers, atrial natriuretic peptide (ANP) and ß-myosin heavy chain (ß-MHC), resulting in myocyte hypertrophy. Candesartan, irbesartan, and valsartan had greater effects than losartan for blockade of fibrotic and hypertrophic effects of Ang II. Our data support the concept whereby sustained AT1R stimulation contributes to the development of myocardial fibrosis and hypertrophy, and advances understanding of this complex AT1R signaling, including fibroblasts-myocytes communication during pathological conditions.


Assuntos
Cardiomiopatias , Fator de Crescimento Transformador beta , Animais , Humanos , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Cardiomiopatias/metabolismo , Fibroblastos , Fibrose , Hipertrofia/patologia , Células Musculares/metabolismo , Miocárdio/metabolismo , Receptores de Angiotensina , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo
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