RESUMO
Persistent myocardial hypertrophy frequently leads to heart failure (HF). Intramyocardial triacylglycerol (TAG) accumulation is closely related with cardiac remodeling and abnormal contractile function. Adipose triglyceride lipase (ATGL), a key enzyme in TAG metabolism, regulates cardiac function. However, its associated molecular pathways have not been fully defined. Here, cardiac hypertrophy and HF were induced in wild-type (WT) or ATGL knockout (KO) mice through transverse aortic constriction (TAC) for up to 4 weeks. TAC in WT mice significantly reduced cardiac function and autophagy while enhancing left ventricular hypertrophy, interstitial fibrosis, inflammatory response, superoxide generation, and cardiomyocyte apoptosis, accompanied with upregulation of the proteasome activity, reduction of PTEN level and activation of AKT-mTOR signaling, and these effects were further aggravated in ATGL KO mice. Interestingly, ATGL KO-mediated cardiac dysfunction and remodeling were markedly reversed by proteasome inhibitor (epoxomicin) or autophagic activator (rapamycin), but accelerated by PTEN inhibitor (VO-OHpic) or autophagy inhibitor 3-MA. Mechanistically, ATGL KO upregulated proteasome expression and activity, which in turn mediates PTEN degradation leading to activation of AKT-mTOR signaling and inhibition of autophagy, thereby enhancing hypertrophic remodeling and HF. In conclusion, ATGL KO contributes to TAC-induced cardiac dysfunction and adverse remodeling probably associated with the proteasome-PTEN-mTOR-autophagy pathway. Therefore, modulation of this pathway may have a therapeutic effect potential for hypertrophic heart disease. TAC-induced downregulation of ATGL results in increased proteasome (ß1i/ß2i/ß5i) activity, which in turn promotes degradation of PTEN and activation of AKT-mTOR signaling and then inhibits autophagy and ATP production, thereby leading to cardiac hypertrophic remodeling and dysfunction. Conversely, blocking proteasome activity or activating autophagy attenuates these effects.
Assuntos
Insuficiência Cardíaca , Complexo de Endopeptidases do Proteassoma , Camundongos , Animais , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cardiomegalia/genética , Cardiomegalia/metabolismo , Insuficiência Cardíaca/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Camundongos Knockout , Autofagia , Miócitos Cardíacos/metabolismo , Camundongos Endogâmicos C57BLRESUMO
The immunoproteasome contains three catalytic subunits (ß1i, ß2i and ß5i) that are important modulators of immune cell homeostasis. A previous study showed a correlation between ß5i and human atherosclerotic plaque instability; however, the causative role of ß5i in atherosclerosis and the underlying mechanisms remain unknown. Here we explored this issue in apolipoprotein E (Apoe) knockout (eKO) mice with genetic deletion or pharmacological inhibition of ß5i. We found that ß5i expression was upregulated in lesional macrophages after an atherogenic diet (ATD). ß5i/Apoe double KO (dKO) mice fed on the ATD had a significant decrease in both lesion area and necrotic core area, compared with eKO controls. Moreover, dKO mice had less caspase-3+ apoptotic cell accumulation but enhanced efferocytosis of apoptotic cells and increased expression of Mer receptor tyrosine kinase (MERTK). Consistently, similar phenotypes were observed in eKO mice transplanted with dKO bone marrow or treated with ß5i-specific inhibitor PR-957. Mechanistic studies in vitro revealed that ß5i deletion reduced IκBα degradation and inhibited NF-κB activation, promoting Mertk transcription and efferocytosis, thereby attenuating apoptotic cell accumulation. In conclusion, we demonstrate that ß5i plays an important role in diet-induced atherosclerosis by altering MERTK-mediated efferocytosis. ß5i might be a potential pharmaceutical target against atherosclerosis. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Assuntos
Apolipoproteínas E/genética , Aterosclerose/metabolismo , Dieta Hiperlipídica , Macrófagos/metabolismo , Fagocitose/fisiologia , c-Mer Tirosina Quinase/metabolismo , Animais , Apolipoproteínas E/metabolismo , Apoptose/fisiologia , Aterosclerose/genética , Aterosclerose/patologia , Caspase 3/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Oligopeptídeos/farmacologia , Complexo de Endopeptidases do Proteassoma , Inibidores de Proteassoma/farmacologiaRESUMO
Inflammation is associated with retinal diseases. Our recent data demonstrate that immunoproteasome catalytic subunit ß2i contributes to angiotensin II (Ang II)-induced retinopathy in mice. Here, we investigated the role of another catalytic subunit ß5i in regulating retinopathy and its underlying mechanisms. We induced a murine model of retinopathy by infusing Ang II (3,000 ng/kg/min) for 3 weeks into wild-type (WT) mice, ß5i-knockout (KO) mice, or WT mice injected with either adenovirus-expressing ß5i (Ad-ß5i) or angiotensin II type 1 receptor (AT1R)-associated protein (Ad-ATRAP), which inhibits AT1R. The ß5i expression and chymotrypsin-like activity were most significantly elevated in Ang II-infused retinas and serum from patients with hypertensive retinopathy. Moreover, Ang II infusion-induced retinopathy was markedly attenuated in ß5i-KO mice but aggravated in Ad-ß5i-injected mice. Accordingly, ß5i KO markedly restored Ang II-induced downregulation of ATRAP and activation of AT1R downstream mediators, which was further enhanced in Ad-ß5i-injected mice. Interestingly, overexpression of ATRAP significantly abrogated Ang II-induced retinopathy in Ad-ß5i-injected mice. This study found that ß5i promoted Ang II-induced retinopathy by promoting ATRAP degradation and activation of AT1R-mediated signals.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Retinopatia Hipertensiva/sangue , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteólise , Adulto , Idoso , Angiotensina II/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Vetores Genéticos , Humanos , Retinopatia Hipertensiva/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Transdução de Sinais/genéticaRESUMO
Monocyte and adhesion infiltration into the arterial subendothelium are initial steps in hypertension development. The endothelial intercellular adhesion molecule-1 (ICAM-1) has been implicated in the recruitment and adhesion of leukocytes in several cardiac diseases. However, the role of ICAM-1 in angiotensin II (Ang II)-induced hypertension development remains unknown. Hypertension was induced by administering an infusion of Ang II (1000 ng/kg/min) to wild-type (WT) mice treated with an IgG control or ICAM-1 neutralizing antibody (1 and 2 mg/mouse/day, respectively). Blood pressure was determined using the tail-cuff system. Vascular remodeling was assessed by performing a histological examination. Inflammation and reactive oxygen species (ROS) levels were determined by using immunostaining. Vascular dysfunction was assessed by aortic ring assay. The expression of fibrotic markers, cytokines and NOX was evaluated by quantitative real-time PCR analysis. Our results demonstrate that Ang II infusion markedly increased the ICAM-1 level in the aorta. Blocking ICAM-1 with a neutralizing antibody significantly attenuated Ang II-induced arterial hypertension, vascular hypertrophy, fibrosis, macrophage infiltration, and ROS production and improved vascular relaxation. In conclusion, ICAM-1-mediated monocyte adhesion and migration play a critical role in Ang II-induced arterial hypertension and vascular dysfunction. ICAM-1 inhibitors may represent a new therapeutic strategy for the treatment of this disease.
Assuntos
Angiotensina II/metabolismo , Endotélio Vascular/fisiopatologia , Hipertensão/prevenção & controle , Molécula 1 de Adesão Intercelular , Animais , Aorta/metabolismo , Adesão Celular/fisiologia , Células Cultivadas , Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertensão/metabolismo , Molécula 1 de Adesão Intercelular/imunologia , Molécula 1 de Adesão Intercelular/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Intercellular adhesion molecule-1 (ICAM-1) is a member of an immunoglobulin-like superfamily of adhesion molecules that mediate leukocyte adhesion to vascular endothelium and are involved in several cardiovascular diseases, including ischemia-reperfusion injury, myocardial infarction, and atherosclerosis. However, the role of ICAM-1 in angiotensin II (ANG II)-induced cardiac remodeling in mice remains unclear. Wild-type mice were administered an IgG control or ICAM-1 neutralizing antibody (1 and 2 mg/mouse, respectively) and ANG II (1,000 ng·kg-1·min-1) for up to 14 days. Cardiac contractile function and structure were detected by echocardiography. Hypertrophy, fibrosis, and inflammation were assessed by histological examination. The infiltration of lymphocyte function-associated antigen-1 (LFA-1+) monocytes/macrophages was assessed by immunostaining. The mRNA expression of genes was evaluated by quantitative RT-PCR analysis. Protein levels were tested by immunoblotting. We found that ICAM-1 expression in ANG II-infused hearts and ICAM-1 levels in serum from human patients with heart failure were significantly increased. Moreover, ANG II infusion markedly enhanced ANG II-induced hypertension, caused cardiac contractile dysfunction, and promoted cardiac hypertrophy, fibrosis, and LFA-1+ macrophage infiltration. Conversely, blockage of ICAM-1 with a neutralizing antibody dose-dependently attenuated these effects. Moreover, our in vitro data further demonstrated that blocking ICAM-1 inhibited ANG II-induced LFA-1+ macrophage adhesion to endothelial cells and migration. In conclusion, these results provide novel evidence that blocking ICAM-1 exerts a protective effect in ANG II-induced cardiac remodeling at least in part through the modulation of adhesion and infiltration of LFA-1+ macrophages in the heart. Inhibition of ICAM-1 may represent a new therapeutic approach for hypertrophic heart diseases.NEW & NOTEWORTHY Leukocyte adhesion to vascular endothelium is a critical step in cardiovascular diseases. ICAM-1 is a member of immunoglobulin-like superfamily of adhesion molecules that binds LFA-1 to mediate leukocytes adhesion and migration. However, the significance of ICAM-1 in ANG II-induced cardiac remodeling remains unclear. This study reveals that blocking of ICAM-1 prevents ANG II-induced cardiac remodeling via modulating adhesion and migration of LFA-1+ monocytes, may serve as a novel therapeutic target for hypertensive cardiac diseases.
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Adesão Celular , Endotélio Vascular/metabolismo , Insuficiência Cardíaca/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Monócitos/fisiologia , Angiotensina II/toxicidade , Animais , Anticorpos Neutralizantes/imunologia , Endotélio Vascular/patologia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/sangue , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/imunologia , Antígeno-1 Associado à Função Linfocitária/genética , Antígeno-1 Associado à Função Linfocitária/metabolismo , Macrófagos/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Contração MiocárdicaRESUMO
Aims: Chemokine-mediated monocyte infiltration into the damaged heart represents an initial step in inflammation during cardiac remodelling. Our recent study demonstrates a central role for chemokine receptor CXCR2 in monocyte recruitment and hypertension; however, the role of chemokine CXCL1 and its receptor CXCR2 in angiotensin II (Ang II)-induced cardiac remodelling remain unknown. Methods and results: Angiotensin II (1000 ng kg-1 min-1) was administrated to wild-type (WT) mice treated with CXCL1 neutralizing antibody or CXCR2 inhibitor SB265610, knockout (CXCR2 KO) or bone marrow (BM) reconstituted chimeric mice for 14 days. Microarray revealed that CXCL1 was the most highly upregulated chemokine in the WT heart at Day 1 after Ang II infusion. The CXCR2 expression and the CXCR2+ immune cells were time-dependently increased in Ang II-infused hearts. Moreover, administration of CXCL1 neutralizing antibody markedly prevented Ang II-induced hypertension, cardiac dysfunction, hypertrophy, fibrosis, and macrophage accumulation compared with Immunoglobulin G (IgG) control. Furthermore, Ang II-induced cardiac remodelling and inflammatory response were also significantly attenuated in CXCR2 KO mice and in WT mice treated with SB265610 or transplanted with CXCR2-deficienct BM cells. Co-culture experiments in vitro further confirmed that CXCR2 deficiency inhibited macrophage migration and activation, and attenuated Ang II-induced cardiomyocyte hypertrophy and fibroblast differentiation through multiple signalling pathways. Notably, circulating CXCL1 level and CXCR2+ monocytes were higher in patients with heart failure compared with normotensive individuals. Conclusions: Angiotensin II-induced infiltration of monocytes in the heart is largely mediated by CXCL1-CXCR2 signalling which initiates and aggravates cardiac remodelling. Inhibition of CXCL1 and/or CXCR2 may represent new therapeutic targets for treating hypertensive heart diseases.
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Cardiomegalia/metabolismo , Quimiocina CXCL1/fisiologia , Monócitos/fisiologia , Receptores de Interleucina-8B/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiotensina II , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/patologia , Cardiomegalia/prevenção & controle , Movimento Celular/fisiologia , Quimiocina CXCL1/antagonistas & inibidores , Quimiocina CXCL1/sangue , Feminino , Fibrose , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Miocárdio/patologia , Receptores de Interleucina-8B/sangue , Receptores de Interleucina-8B/deficiência , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologiaRESUMO
BACKGROUND/AIMS: Angiotensin II (Ang II)-mediated hypertension is a major risk factor for cardiovascular diseases. Ang II induces changes in vessel structure and function through the activation of genes related to signaling pathways. However, the changes in the gene expression profiles of blood vessels in response to Ang II remain unclear. METHODS: Wild-type C57BL/6 mice were infused with Ang II (1500 ng/kg/min) using an osmotic pump for 1, 3, and 7 days. Vascular wall inflammation and remodeling were evaluated by pathological examination. Time-series microarray and quantitative PCR analyses were performed. Bioinformatics analyses were conducted to identify key genes, pathways, and biological processes. RESULTS: After Ang II infusion, blood pressure and aortic remodeling were increased over time. Microarray analysis identified a totally of 3631 differentially expressed genes in aortas at days 1, 3, and 7 of Ang II infusion. These genes were involved in multiple biological processes, including cell adhesion, angiogenesis, cell migration, protein phosphorylation, immune system, and cell cycle, which may play important roles in regulating Ang II-induced arterial injury during hypertension. The genes were classified into 50 profiles by hierarchical cluster analysis, and finally, 14 significant profiles were identified. Among these genes, protein kinase cAMP-activated catalytic subunit alpha (Prkaca), a gene that directly regulated 137 neighboring genes, was located at the center of the gene network in Ang II-infused aortas. Further, Prkaca protein expression and cAMP level were downregulated in a time-dependent manner in Ang II-infused aortas. CONCLUSIONS: The combined use of DNA microarrays and cluster and gene network analyses identified Prkaca as a key Ang II-responsive gene that may mediate early vascular injury and hypertension.
Assuntos
Angiotensina II/farmacologia , Transcriptoma/efeitos dos fármacos , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Pressão Sanguínea/efeitos dos fármacos , Análise por Conglomerados , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Redes Reguladoras de Genes/efeitos dos fármacos , Hipertensão/etiologia , Hipertensão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Fatores de TempoRESUMO
INTRODUCTION: Leukocyte infiltration is an early event during cardiac remodeling frequently leading to heart failure (HF). Integrins mediate leukocyte infiltration during inflammation. However, the importance of specific integrins in hypertensive cardiac remodeling is still unclear. OBJECTIVES: To elucidate the significance of CD11b in hypertensive cardiac remodeling. METHODS: Angiotensin (Ang II) or deoxycorticosterone acetate (DOCA)-salt was used to induce cardiac remodeling in mice of gene knockout (KO), bone marrow (BM) chimera, and the CD11b neutralizing antibody or agonist leukadherin-1 (LA1) treatment. RESULTS: Our microarray data showed that integrin subunits Itgam (CD11b) and Itgb2 (CD18) were the most highly upregulated in Ang II-infused hearts. CD11b expression and CD11b/CD18+ myelomonocytes were also time-dependently increased. KO or pharmacological blockade of CD11b greatly attenuated cardiac remodeling and macrophage infiltration and M1 polarization induced by Ang II or DOCA-salt. This protection was verified in wild-type mice transplanted with CD11b-deficient BM cells. Conversely, administration of CD11b agonist LA1 showed the opposite effects. Further, CD11b KO reduced Ang II-induced macrophage adhesion and M1 polarization, leading to reduction of cardiomyocyte enlargement and fibroblast differentiation in vitro. The numbers of CD14+CD11b+CD18+ monocytes and CD15+CD11b+CD18+ granulocytes were obviously higher in HF patients than in normal controls. CONCLUSION: Our data demonstrate an important role of CD11b+ myeloid cells in hypertensive cardiac remodeling, and suggest that HF may benefit from targeting CD11b.
Assuntos
Acetato de Desoxicorticosterona , Insuficiência Cardíaca , Hipertensão , Humanos , Animais , Camundongos , Remodelação Ventricular/fisiologia , Acetato de Desoxicorticosterona/efeitos adversos , Macrófagos/metabolismo , Hipertensão/metabolismo , IntegrinasRESUMO
The heart undergoes pathological cardiac hypertrophy as an adaptive response to prolonged pathological stimulation, leading to cardiomyocyte hypertrophy, fibroblast proliferation, and an increase in extracellular matrix. Chinese medicine monomers are now receiving much attention for the treatment of cardiac hypertrophy and myocardial remodeling. Biochanin A (BCA) is a kind of flavonoid structural monomer, which has a certain therapeutic effect on bone thinning disease, aging syndrome, lung cancer, etc. Moreover, it exhibits hypoglycemic, anti-inflammatory, anti-oxidation, anti-bacteria and other pharmacological properties. It is still unknown whether BCA has an impact on the mechanism of TAC-induced cardiac hypertrophy. Here, cardiac remodeling was induced by TAC. BCA was injected intraperitoneally at 25 and 50 mg/kg/day one week in advance. Masson, WGA, DHE and other pathological staining and serum were used to detect the inhibitory effect of BCA on cardiac hypertrophy in mice. The anti-hypertrophic effect of BCA was demonstrated by studying the pathological manifestations of Neonatal rat cardiomyocytes (NRCMs) and cardiac fibroblasts (CFs) in vitro. The results showed that BCA significantly reduced TAC-induced fibrosis, inflammation, oxidative stress, and myocardial hypertrophy. BCA inhibited Ang II-induced cell hypertrophy and oxidative stress in NRCMs in vitro and Ang II-induced CF migration, proliferation, and collagen secretion. This suggests that BCA plays a key role in inhibiting the progression of myocardial remodeling, suggesting that BCA may be a promising agent for the treatment of myocardial hypertrophy and fibrosis.
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Cardiomegalia , Miocárdio , Ratos , Camundongos , Animais , Cardiomegalia/patologia , Miocárdio/patologia , Miócitos Cardíacos , Fibrose , Camundongos Endogâmicos C57BL , Angiotensina II/farmacologia , Remodelação VentricularRESUMO
Persistent pressure overload commonly leads to pathological cardiac hypertrophy and remodeling, ultimately leading to heart failure (HF). Cardiac remodeling is associated with the involvement of immune cells and the inflammatory response in pathogenesis. The macrophage-1 antigen (Mac-1) is specifically expressed on leukocytes and regulates their migration and polarization. Nonetheless, the involvement of Mac-1 in cardiac remodeling and HF caused by pressure overload has not been determined. The Mac-1-knockout (KO) and wild-type (WT) mice were subjected to transverse aortic constriction (TAC) for 6 weeks. Echocardiography and pressure-volume loop assessments were used to evaluate cardiac function, and cardiac remodeling and macrophage infiltration and polarization were estimated by histopathology and molecular techniques. The findings of our study demonstrated that Mac-1 expression was markedly increased in hearts subjected to TAC treatment. Moreover, compared with WT mice, Mac-1-KO mice exhibited dramatically ameliorated TAC-induced cardiac dysfunction, hypertrophy, fibrosis, oxidative stress and apoptosis. The potential positive impacts may be linked to the inhibition of macrophage infiltration and M1 polarization via reductions in NF-kB and STAT1 expression and upregulation of STAT6. In conclusion, this research reveals a new function of Mac-1 deficiency in reducing pathological cardiac remodeling and HF caused by pressure overload. Additionally, inhibiting Mac-1 could be a potential treatment option for patients with HF in a clinical setting.
Assuntos
Insuficiência Cardíaca , Antígeno de Macrófago 1 , Humanos , Camundongos , Animais , Antígeno de Macrófago 1/metabolismo , Remodelação Ventricular/genética , Transdução de Sinais , Insuficiência Cardíaca/metabolismo , Cardiomegalia/metabolismo , Camundongos Knockout , Macrófagos/metabolismoRESUMO
OBJECTIVE: In order to study the feature of T cell TCR-CD3 complex-mediated gene in lead poisoning patients. METHODS: Real-time PCR with SYBR Green I technique was used for determination of the expression levels of CD3 genes in peripheral blood mononuclear cells of 46 cases lead poisoning patients (11 cases in observation group and 35 cases in mild lead poisoning group) and 31 cases in control group. RESULTS: The median expression levels of CD3γ gene in observation group and mild lead poisoning group (6.89%, 5.87 %) were higher than the control group (P < 0.05). The median expression levels of CD3δ gene in observation group and mild lead poisoning group (0.54%, 0.70%) were lower than the control group (P < 0.05). The median expression levels of CD3ε gene in observation group and mild lead poisoning group (10.22%, 6.08%) were higher than the control group (P < 0.05). A significant Positive correlation was found between CD3γ, CD3ε and seniority in lead poisoning patients. A significant negative correlation was found between CD3ε and blood ZPP, urea δ-ALA (r = -0.358, P < 0.05; r = -0.385, P < 0.05), but there was no significant correlation between them after controlling for blood lead, urea lead. The expression levels of CD3 genes prove to be a descending order of CD3γ, CD3ε, CD3δ in control group, while it was changed for CD3ε, CD3γ, CD3δ in the observation group as well as in mild lead poisoning group. CONCLUSION: Expression of T cell TCR-CD3 complex-mediated gene was changed in lead poisoning patients, it might be related to the body immunodeficiency. The expression level of CD3ε gene can be used as sensitive immune function screening indicator in Lead poisoning patients.
Assuntos
Intoxicação por Chumbo/imunologia , Doenças Profissionais/imunologia , Complexo Receptor-CD3 de Antígeno de Linfócitos T/metabolismo , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Adulto JovemRESUMO
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 , MacrófagosRESUMO
Doxorubicin, a widely used chemotherapeutic drug in clinical oncology, causes a series of cardiac side effects referred to as doxorubicin-induced cardiotoxicity. Hyperhomocysteinaemia is an independent risk factor for multiple cardiovascular diseases. However, whether hyperhomocysteinaemia contributes to doxorubicin-induced cardiotoxicity is currently unknown. In this study, we explored the pathogenic effects of hyperhomocysteinaemia induced by dietary methionine supplementation (2% wt/wt in rodent chow) in a mouse model of doxorubicin-induced cardiotoxicity. Our data showed that methionine supplementation doubled serum homocysteine levels, inducing mild hyperhomocysteinaemia. Doxorubicin at a cumulative dosage of 25 mg/kg body weight led to significant weight loss and severe cardiac dysfunction, which were further exacerbated by methionine-induced mild hyperhomocysteinaemia. Doxorubicin-induced cardiac atrophy, cytoplasmic vacuolisation, myofibrillar disarray and loss, as well as cardiac fibrosis, were also exacerbated by methionine-induced mild hyperhomocysteinaemia. Additional folic acid supplementation (0.006% wt/wt) prevented methionine-induced hyperhomocysteinaemia and inhibited hyperhomocysteinaemia-aggravated cardiac dysfunction and cardiomyopathy. In particular, hyperhomocysteinaemia increased both serum and cardiac oxidative stress, which could all be inhibited by folic acid supplementation. Therefore, we demonstrated for the first time that hyperhomocysteinaemia could exacerbate doxorubicin-induced cardiotoxicity in mice, and the pathogenic effects of hyperhomocysteinaemia might at least partially correlate with increased oxidative stress and could be prevented by folic acid supplementation. Our study provides preliminary experimental evidence for the assessment of hyperhomocysteinaemia as a potential risk factor for chemotherapy-induced cardiotoxicity in cancer patients.
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Hypertriglyceridemia (HTG) is an independent risk factor for atherosclerosis. However, its impact on non-atherosclerotic cardiovascular diseases remains largely unknown. Glycosylphosphatidylinositol anchored high-density lipoprotein binding protein 1 (GPIHBP1) is essential for the hydrolysis of circulating triglycerides and loss of functional GPIHBP1 causes severe HTG. In this study, we used Gpihbp1 knockout (GKO) mice to investigate the potential effects of HTG on non-atherosclerotic vascular remodeling. We compared the aortic morphology and gene expressions between three-month-old and ten-month-old GKO mice and their age-matched wild-type controls. We also conducted similar comparisons between GKO mice and wild-type controls in an angiotensin II (AngII)-induced vascular remodeling model. Our data showed that the intima-media wall of ten-month-old GKO mice but not three-month-olds was significantly thickened compared to wild-type controls. Moreover, ten-month-old GKO mice but not three-month-olds had increased aortic macrophage infiltration and perivascular fibrosis, along with increased endothelial activation and oxidative stress. Similarly, the AngII-induced vascular remodeling, as well as endothelial activation and oxidative stress, were also exacerbated in the GKO mice compared to wild-type controls. In conclusion, we demonstrated that severe HTG caused by Gpihbp1 deficiency could facilitate the onset and progression of non-atherosclerotic vascular remodeling through endothelial activation and oxidative stress in mice.
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Aterosclerose , Hipertrigliceridemia , Receptores de Lipoproteínas , Animais , Camundongos , Aterosclerose/genética , Hipertrigliceridemia/genética , Camundongos Knockout , Estresse Oxidativo , Receptores de Lipoproteínas/genética , Receptores de Lipoproteínas/metabolismo , Remodelação Vascular/genéticaRESUMO
Three novel transition metal complexes (Hapy)(2)[M(DCA)(2)]·6H(2)O (M = Mn(II) (1), Ni(II) (2), Cu(II) (3); DCA = demethylcantharate, 7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylate, C(8)H(8)O(5); Hapy = 2-aminopyridine acid, C(5)H(7)N(2)) were synthesized and characterized by elemental analysis, infrared spectra, thermogravimetric analysis and X-ray diffraction. DNA binding properties of the complexes were investigated by electronic absorption spectra, fluorescence spectra and viscosity measurements. Results indicated the complexes could bind to DNA through partial intercalation mode with binding constants K ( b )/(L·mol(-1)) of 1.91 × 10(4) (1), 5.13 × 10(4) (2) and 1.12 × 10(5) (3) at 298 K. Meanwhile, the interactions of the complexes with BSA were also studied by fluorescence spectra. The results suggested that the complexes could quench the fluorescence of BSA through static quenching with the binding constants K ( A )/(L·mol(-1)) of 1.44 × 10(6) (1), 1.14 × 10(7) (2) and 2.98 × 10(4) (3). And the main contribution was tryptophan residues of BSA. The antiproliferative activity test revealed that complexes showed more intense inhibition ratios against human hepatoma cells lines and human gastric cancer cells lines in vitro. Copper(II) complex (3) possesses the strongest inhibition ratio against human hepatoma cells.
Assuntos
Aminopiridinas/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Cantaridina/análogos & derivados , Cantaridina/química , Compostos Organometálicos/metabolismo , Compostos Organometálicos/farmacologia , Soroalbumina Bovina/metabolismo , Antineoplásicos/química , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cobre/química , Cristalografia por Raios X , Humanos , Manganês/química , Níquel/química , Compostos Organometálicos/química , Ligação Proteica , Análise Espectral , ViscosidadeRESUMO
In the title compound, C(16)H(16)N(2)O(6), the dihedral angle between the two pyrrolidine rings is 79.38â (14)°.
RESUMO
In the structure of the title complex, (C(7)H(7)N(2)S)(2)[Cd(C(8)H(8)O(5))(2)]·6H(2)O, the Cd(II) atom is located on an inversion center and is O,O',O''-chelated by two symmetry-related 7-oxabicyclo-[2.2.1]heptane-2,3-dicarboxyl-ate ligands in a distorted octa-hedral geometry. The 2-amino-benzothia-zolium cation links with the Cd complex anion via N-Hâ¯O hydrogen bonding. Extensive O-Hâ¯O and N-Hâ¯O hydrogen bonds involving lattice water mol-ecules occur in the crystal structure.
RESUMO
The polymeric title complex, [Co(C(8)H(8)O(5))(H(2)O)(2)](n) was synthesized by reaction of cobalt acetate with 7-oxabicyclo-[2,2,1]heptane-2,3-dicarb-oxy-lic anhydride. The Co(II) ion is six-coordinated in a distorted octa-hedral environment, binding to two water O atoms, to the ether O atom of the bicyclo-heptane unit, to two carboxyl-ate O atoms from two different carboxyl-ate groups of the same anion and to one carboxyl-ate O atom from a symmetry-related anion. The bridging character of the dianion leads to the formation of ribbons along [001]. The ribbons are linked into a layered network parallel to (010) by several O-Hâ¯O hydrogen-bonding inter-actions involving the coordinating water mol-ecules as donors and the carboxyl-ate O atoms of neighbouring ribbons as acceptors. The crystal under investigation was an inversion twin.
RESUMO
In the title hydrated mol-ecular salt, (C(7)H(7)N(2)S)(2)[Zn(C(8)H(8)O(5))(2)]·6H(2)O, which is isotypic with its Mn(II), Co(II) and Ni(II) analogues, the Zn(2+) ion lies on a crystallographic inversion centre and a distorted ZnO(6) octa-hedral coordination geometry arises from the two doubly deprotonated O,O',O''-tridentate ligands. In the crystal, the components are linked by N-Hâ¯O(a), N-Hâ¯O(w), O(w)-Hâ¯O(a) and O(w)-Hâ¯O(w) hydrogen bonds (w = water and a = anion).
RESUMO
Cardiac remodeling is an important mechanism of heart failure, which frequently results from leukocyte infiltration. Vascular cellular adhesion molecule-1 (VCAM-1) plays a critical role in leukocyte adhesion and transmigration. However, the importance of VCAM-1 in the development of angiotensin II (Ang II)-induced cardiac remodeling remains unclear. Wild-type (WT) mice were infused with Ang II (1,000 ng/kg/min) for 14 days and simultaneously treated with VCAM-1 neutralizing antibody (0.1 or 0.2 mg) or IgG control. Systolic blood pressure (SBP) and cardiac function were detected by a tail-cuff and echocardiography. Cardiac remodeling was evaluated by histological staining. Adhesion and migration of bone marrow macrophages (BMMs) were evaluated in vitro. Our results indicated that VCAM-1 levels were increased in the serum of patients with heart failure (HF) and the hearts of Ang II-infused mice. Furthermore, Ang II-caused hypertension, cardiac dysfunction, hypertrophy, fibrosis, infiltration of VLA-4+ BMMs and oxidative stress were dose-dependently attenuated in mice administered VCAM-1 neutralizing antibody. In addition, blocking VCAM-1 markedly alleviated Ang II-induced BMMs adhesion and migration, therefore inhibited cardiomyocyte hypertrophy and fibroblast activation. In conclusion, the data reveal that blocking VCAM-1 ameliorates hypertensive cardiac remodeling by impeding VLA-4+ macrophage infiltration. Selective blockage of VCAM-1 may be a novel therapeutic strategy for hypertensive cardiac diseases.