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Efferocytosis refers to the process by which phagocytes remove apoptotic cells and related apoptotic products. It is essential for the growth and development of the body, the repair of damaged or inflamed tissues, and the balance of the immune system. Damaged efferocytosis will cause a variety of chronic inflammation and immune system diseases. Many studies show that efferocytosis is a process mediated by mitochondria. Mitochondrial metabolism, mitochondrial dynamics, and communication between mitochondria and other organelles can all affect phagocytes' clearance of apoptotic cells. Therefore, targeting mitochondria to modulate phagocyte efferocytosis is an anticipated strategy to prevent and treat chronic inflammatory diseases and autoimmune diseases. In this review, we introduced the mechanism of efferocytosis and the pivoted role of mitochondria in efferocytosis. In addition, we focused on the therapeutic implication of drugs targeting mitochondria in diseases related to efferocytosis dysfunction.
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Cardiovascular disease is the leading cause of death worldwide, and it's of great importance to understand its underlying mechanisms and find new treatments. Sphingosine 1-phosphate (S1P) is an active lipid that exerts its effects through S1P receptors on the cell surface or intracellular signal, and regulates many cellular processes such as cell growth, cell proliferation, cell migration, cell survival, and so on. S1PR modulators are a class of modulators that can interact with S1PR subtypes to activate receptors or block their activity, exerting either agonist or functional antagonist effects. Many studies have shown that S1P plays a protective role in the cardiovascular system and regulates cardiac physiological functions mainly through interaction with cell surface S1P receptors (S1PRs). Therefore, S1PR modulators may play a therapeutic role in cardiovascular diseases. Here, we review five S1PRs and their functions and the progress of S1PR modulators. In addition, we focus on the effects of S1PR modulators on atherosclerosis, myocardial infarction, myocardial ischaemia/reperfusion injury, diabetic cardiovascular diseases, and myocarditis, which may provide valuable insights into potential therapeutic strategies for cardiovascular disease.
Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Lisofosfolipídeos , Esfingosina/análogos & derivados , Humanos , Receptores de Esfingosina-1-Fosfato/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Receptores de Lisoesfingolipídeo/metabolismo , Sistema Cardiovascular/metabolismoRESUMO
Ischemia-reperfusion injury is a complex hemodynamic pathology that is a leading cause of death worldwide and occurs in many body organs. Numerous studies have shown that mitochondria play an important role in the occurrence mechanism of ischemia-reperfusion injury and that mitochondrial structural abnormalities and dysfunction lead to the disruption of the homeostasis of the whole mitochondria. At this time, mitochondria are not just sub-organelles to produce ATP but also important targets for regulating ischemia-reperfusion injury; therefore, drugs targeting mitochondria can serve as a new strategy to treat ischemia-reperfusion injury. Based on this view, in this review, we discuss potential therapeutic agents for both mitochondrial structural abnormalities and mitochondrial dysfunction, highlighting the application and prospects of targeted mitochondrial drugs in the treatment of ischemia-reperfusion injury, and try to provide new ideas for the clinical treatment of the ischemia-reperfusion injury.
Assuntos
Traumatismo por Reperfusão , Humanos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Mitocôndrias/patologia , Espécies Reativas de Oxigênio/uso terapêuticoRESUMO
Heart failure remains a considerable clinical and public health problem, it is the dominant cause of death from cardiovascular diseases, besides, cardiovascular diseases are one of the leading causes of death worldwide. The survival of patients with heart failure continues to be low with 45-60% reported deaths within five years. Apoptosis, necrosis, autophagy, and pyroptosis mediate cardiac cell death. Acute cell death is the hallmark pathogenesis of heart failure and other cardiac pathologies. Inhibition of pyroptosis, autophagy, apoptosis, or necrosis reduces cardiac damage and improves cardiac function in cardiovascular diseases. Pyroptosis is a form of inflammatory deliberate cell death that is characterized by the activation of inflammasomes such as NOD-like receptors (NLR), absent in melanoma 2 (AIM2), interferon-inducible protein 16 (IFI-16), and their downstream effector cytokines: Interleukin IL-1ß and IL-18 leading to cell death. Recent studies have shown that pyroptosis is also the dominant cell death process in cardiomyocytes, cardiac fibroblasts, endothelial cells, and immune cells. It plays a crucial role in the pathogenesis of cardiac diseases that contribute to heart failure. This review intends to summarize the therapeutic implications targeting pyroptosis in the main cardiac pathologies preceding heart failure.
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Doenças Cardiovasculares , Insuficiência Cardíaca , Caspase 1/metabolismo , Citocinas/metabolismo , Células Endoteliais/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Humanos , Inflamassomos/metabolismo , Interferons , Interleucina-18 , Interleucina-1beta/metabolismo , Interleucinas , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR , Necrose , PiroptoseRESUMO
Sepsis is an increasingly worldwide problem; it is currently regarded as a complex life-threatening dysfunction of one or more organs as a result of dysregulated host immune response to infections. The heart is one of the most affected organs, as roughly 10% to 70% of sepsis cases are estimated to turn into sepsis-induced cardiomyopathy (SIC). SIC can be defined as a reversible myocardial dysfunction characterized by dilated ventricles, impaired contractility, and decreased ejection fraction. Mitochondria play a critical role in the normal functioning of cardiac tissues as the heart is highly dependent on its production of adenosine triphosphate (ATP), its damage during SIC includes morphology impairment, mitophagy, biogenesis disequilibrium, electron transport chain disturbance, molecular damage from the actions of pro-inflammatory cytokines and many other different impairments that are major contributing factors to the severity of SIC. Although mitochondria-targeted therapies usage is still inadequate in clinical settings, the preclinical study outcomes promise that the implementation of these therapies may effectively treat SIC. This review summarizes the different therapeutic strategies targeting mitochondria structure, quality, and quantity abnormalities for the treatment of SIC.
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Myocardial ischaemia-reperfusion injury (MI/RI) refers to the further damage done to ischaemic cardiomyocytes when restoring blood flow. A large body of evidence shows that MI/RI is closely associated with excessive production of mitochondrial reactive oxygen species, mitochondrial calcium overload, disordered mitochondrial energy metabolism, mitophagy, mitochondrial fission, and mitochondrial fusion. According to the way it affects mitochondria, it can be divided into mitochondrial quality abnormalities and mitochondrial quantity abnormalities. Abnormal mitochondrial quality refers to the dysfunction caused by the severe destruction of mitochondria, which then affects the balance of mitochondrial density and number, causing an abnormal mitochondrial quantity. In the past, most of the reports were limited to the study of the mechanism of myocardial ischaemia-reperfusion injury, some of which involved mitochondria, but no specific countermeasures were proposed. In this review, we outline the mechanisms for treating myocardial ischaemia-reperfusion injury from the direction of mitochondria and focus on targeted interventions and drugs to restore mitochondrial health during abnormal mitochondrial quality control and abnormal mitochondrial quantity control. This is an update in the field of myocardial ischaemia-reperfusion injury.
Assuntos
Traumatismo por Reperfusão Miocárdica , Humanos , Mitocôndrias/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio , Miócitos Cardíacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Inflammation-induced lymphangiogenesis is a widely accepted concept. However, most of the inflammatory factors and their related mechanisms have not been clarified. It has been reported that sphingosine-1-phosphate (S1P) is not only closely related to the chronic inflammatory process but also affects angiogenesis. Therefore, we investigated the inflammatory effects of S1P on human lymphatic endothelial cells (HLECs). Our results showed that S1P promotes tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) secretion in HLECs. We also confirmed that S1P-stimulated TNF-α and IL-1ß secretion is mediated through S1P receptor 1 (S1PR1). Using TNF-α siRNA and IL-1ß siRNA, we found that TNF-α and IL-1ß play essential roles in S1P-induced HLEC proliferation, migration, and tube formation. S1P induces phosphorylation of NF-κB p65 and activation of NF-κB nuclear translocation. A S1PR1 antagonist (W146) and NF-κB inhibitor (BAY11-7082) inhibited S1P-induced TNF-α and IL-1ß secretion and prevented NF-κB nuclear translocation. Taken together, the results demonstrated for the first time that S1P promotes the secretion of TNF-α and IL-1ß in HLECs via S1PR1-mediated NF-κB signaling pathways, thus affecting lymphangiogenesis. The study provides a new strategy for finding treatments for lymphangiogenesis-related diseases.
Assuntos
Células Endoteliais/fisiologia , Inflamação/imunologia , Linfangiogênese/imunologia , Organogênese/imunologia , Receptores de Lisoesfingolipídeo/metabolismo , Animais , Movimento Celular , Proliferação de Células , Células Cultivadas , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lisofosfolipídeos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Fosforilação , RNA Interferente Pequeno/genética , Transdução de Sinais , Esfingosina/análogos & derivados , Esfingosina/imunologia , Receptores de Esfingosina-1-Fosfato , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Sphingosine-1-phosphate (S1P), a bioactive metabolite of sphingolipid, has an important role in lymphocyte trafficking, immune responses, vascular and embryonic development, cancer, bone homeostasis, etc. S1P is produced intracellularly and then secreted into the circulation to engage in the above physiological or pathological processes by regulating the proliferation, differentiation and survival of target cells; however, the underlying mechanisms of S1P secretion and function remain poorly understood. Recently, Spinster 2 (SPNS2), a newly identified transporter of S1P, was shown to act as a mediator of intracellular S1P release and play an important role in the regulation of S1P. In this review, we focus on the primary biological characteristics and functions of SPNS2 and provide novel insights into the development of therapies for S1P-related disorders.
Assuntos
Proteínas de Transporte de Ânions/imunologia , Proteínas de Transporte/imunologia , Lisofosfolipídeos/imunologia , Proteínas de Membrana/imunologia , Esfingosina/análogos & derivados , Proteínas de Peixe-Zebra/imunologia , Animais , Proteínas de Transporte de Ânions/metabolismo , Transporte Biológico/imunologia , Proteínas de Transporte/metabolismo , Diferenciação Celular/imunologia , Movimento Celular/imunologia , Sobrevivência Celular/imunologia , Humanos , Lisofosfolipídeos/metabolismo , Proteínas de Membrana/metabolismo , Esfingosina/imunologia , Esfingosina/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismoRESUMO
BACKGROUND AND AIMS: Liver scavenger receptor class B type I (SR-BI) exerts atheroprotective effects through selective lipid uptake (SLU) from high-density lipoprotein cholesterol (HDL-C). Low hepatic SR-BI expression leads to high HDL-C levels in the circulation and an increased risk of atherosclerosis. Furthermore, macrophage SR-BI mediates bidirectional cholesterol flux and may protect against atherogenesis. Previous studies have revealed that miR-24 is closely related to cardiovascular disease (CVD) progression. We aimed to investigate the molecular mechanisms by which miR-24 participates in SR-BI-mediated selective HDL cholesteryl ester (HDL-CE) uptake and further atherogenesis in apoE-/- mice. METHODS: Bioinformatic predictions and luciferase reporter assays were utilized to detect the association between miR-24 and the SR-BI 3' untranslated region (3' UTR), and RT-PCR and western blotting were used to evaluate SR-BI mRNA and protein expression, respectively. The effects of miR-24 on Dil-HDL uptake were determined by flow cytometry assay. Double-radiolabeled HDL (125I-TC-/[3H] CEt-HDL) was utilized to measure the effects of miR-24 on HDL and CE binding and SLU in HepG2 and PMA-treated THP-1â¯cells. In addition, total cholesterol (TC) levels in HepG2 cells were analyzed using enzymatic methods, and macrophage lipid content was evaluated by high-performance liquid chromatography (HPLC) assay. Small interfering RNA (siRNA) and pcDNA3.1(-)-hSR-BI plasmid transfection procedures were utilized to confirm the role of SR-BI in the effects of miR-24 on Dil-HDL uptake, SLU and cholesterol levels in both cell types. Hepatic SR-BI level in apoE-/- mice was measured by western blotting. Liver TC, FC and CE levels and plasma triglycerides (TG), TC and HDL-C levels were evaluated enzymatically using commercial test kits. Atherosclerotic lesion sizes were measured using Oil Red O and hematoxylin-eosin staining. RESULTS: miR-24 directly repressed SR-BI expression by targeting its 3'UTR. In addition, miR-24 decreased Dil-HDL uptake and SLU in HepG2 and THP-1 macrophages. In the presence of HDL, miR-24 decreased TC levels in HepG2 cells and TC, free cholesterol (FC) and CE levels in macrophages. Overexpression and down-regulation assays showed that SR-BI mediated the effects of miR-24 on Dil-HDL uptake, SLU and cholesterol levels. Lastly, miR-24 administration decreased hepatic SR-BI expression and promoted atheromatous plaque formation in apoE-/- mice, findings in line with those of our in vitro studies. CONCLUSIONS: These findings indicate that miR-24 accelerates atherogenesis by repressing SR-BI-mediated SLU from HDL-C.
Assuntos
Aterosclerose/sangue , HDL-Colesterol/sangue , Fígado/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Receptores Depuradores Classe B/metabolismo , Regiões 3' não Traduzidas , Animais , Aterosclerose/genética , Aterosclerose/patologia , Sítios de Ligação , Modelos Animais de Doenças , Células HEK293 , Células Hep G2 , Humanos , Masculino , Camundongos Knockout para ApoE , MicroRNAs/genética , Processamento Pós-Transcricional do RNA , Receptores Depuradores Classe B/genética , Células THP-1RESUMO
Endothelial dysfunction plays a vital role during the initial stage of atherosclerosis. Oxidized low-density lipoprotein (ox-LDL) induces vascular endothelial injury and vessel wall inflammation. Sphingosine-1-phosphate (S1P) exerts numerous vasoprotective effects by binding to diverse S1P receptors (S1PRs; S1PR1-5). A number of studies have shown that in endothelial cells (ECs), S1PR2 acts as a pro-atherosclerotic mediator by stimulating vessel wall inflammation through the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Scavenger receptor class B member I (SR-BI), a high-affinity receptor for apolipoprotein A-I (apoA-I)/high-density lipoprotein (HDL), inhibits nuclear factor-κB (NF-κB) translocation and decreases the plasma levels of inflammatory mediators via the PI3K/Akt pathway. We hypothesized that the inflammatory effects of S1P/S1PR2 on ECs may be regulated by apoA-I/SR-BI. The results showed that ox-LDL, a pro-inflammatory factor, augmented the S1PR2 level in human umbilical vein endothelial cells (HUVECs) in a dose- and time-dependent manner. In addition, S1P/S1PR2 signaling influenced the levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and IL-10, aggravating inflammation in HUVECs. Moreover, the pro-inflammatory effects induced by S1P/S1PR2 were attenuated by SR-BI overexpression and enhanced by an SR-BI inhibitor, BLT-1. Further experiments showed that the PI3K/Akt signaling pathway was involved in this process. Taken together, these results demonstrate that apoA-I/SR-BI negatively regulates S1P/S1PR2-mediated inflammation in HUVECs by activating the PI3K/Akt signaling pathway.
Assuntos
Apolipoproteína A-I/metabolismo , Endotélio Vascular/metabolismo , Lisofosfolipídeos/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Receptores de Lisoesfingolipídeo/agonistas , Receptores Depuradores Classe B/agonistas , Transdução de Sinais , Esfingosina/análogos & derivados , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Apolipoproteína A-I/genética , Células Cultivadas , Ciclopentanos/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/imunologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Interleucina-10/agonistas , Interleucina-10/metabolismo , Interleucina-1beta/agonistas , Interleucina-1beta/metabolismo , Cinética , Lipoproteínas LDL/efeitos adversos , Lipoproteínas LDL/genética , Lipoproteínas LDL/metabolismo , Proteínas Proto-Oncogênicas c-akt/agonistas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Receptores Depuradores Classe B/antagonistas & inibidores , Receptores Depuradores Classe B/genética , Receptores Depuradores Classe B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato , Tiossemicarbazonas/farmacologia , Fator de Necrose Tumoral alfa/agonistas , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Apolipoprotein M (apoM) is a relatively novel apolipoprotein that plays pivotal roles in many dyslipidemia-associated diseases; however, its regulatory mechanisms are poorly understood. Many cytokines have been identified that down-regulate apoM expression in HepG2 cells, among which transforming growth factor-ß (TGF-ß) exerts the most potent effects. In addition, c-Jun, a member of the activated protein 1 (AP-1) family whose activity is modulated by c-Jun N-terminal kinase (JNK), decreases apoM expression at the transcriptional level by binding to the regulatory element in the proximal apoM promoter. In this study, we investigated the molecular mechanisms through which TGF-ß decreases the apoM level in HepG2 cells. The results revealed that TGF-ß inhibited apoM expression at both the mRNA and protein levels in a dose- and time-dependent manner and that it suppressed apoM secretion. These effects were attenuated by treatment of cells with either SP600125 (JNK inhibitor) or c-Jun siRNA. 5Z-7-oxozeaenol [(a TGF-ß-activated kinase 1 (TAK-1) inhibitor)] also attenuated the TGF-ß-mediated inhibition of apoM expression and suppressed the activation of JNK and c-Jun. These results have demonstrated that TGF-ß suppresses apoM expression through the TAK-1-JNK-c-Jun pathway in HepG2 cells.
Assuntos
Apolipoproteínas/genética , Apolipoproteínas/metabolismo , Lipocalinas/genética , Lipocalinas/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Antracenos/farmacologia , Apolipoproteínas M , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Lactonas/farmacologia , Regiões Promotoras Genéticas , Resorcinóis/farmacologia , Fatores de TempoRESUMO
Sphingosine-1-phosphate (S1P), which has emerged as a pivotal signaling mediator that participates in the regulation of multiple cellular processes, is derived from various cells, including vascular endothelial cells. S1P accumulates in lipoproteins, especially HDL, and the majority of free plasma S1P is bound to HDL. We hypothesized that HDL-associated S1P is released through mechanisms associated with the HDL maturation process. ApoA-I, a major HDL apolipoprotein, is a critical factor for nascent HDL formation and lipid trafficking via ABCA1. Moreover, apoA-I is capable of promoting bidirectional lipid movement through SR-BI. In the present study, we confirmed that apoA-I can facilitate the production and release of S1P by HUVECs. Furthermore, we demonstrated that ERK1/2 and SphK activation induced by apoA-I is involved in the release of S1P from HUVECs. Inhibitor and siRNA experiments showed that ABCA1 and SR-BI are required for S1P release and ERK1/2 phosphorylation induced by apoA-I. However, the effects triggered by apoA-I were not suppressed by inhibiting ABCA1/JAK2 or the SR-BI/Src pathway. S1P released due to apoA-I activation can stimulate the (ERK1/2)/SphK1 pathway through S1PR (S1P receptor) 1/3. These results indicated that apoA-I not only promotes S1P release through ABCA1 and SR-BI but also indirectly activates the (ERK1/2)/SphK1 pathway by releasing S1P to trigger their receptors. In conclusion, we suggest that release of S1P induced by apoA-I from endothelial cells through ABCA1 and SR-BI is a self-positive-feedback process: apoA-I-(ABCA1 and SR-BI)-(S1P release)-S1PR-ERK1/2-SphK1-(S1P production)-(more S1P release induced by apoA-I).
Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apolipoproteína A-I/farmacologia , Lisofosfolipídeos/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptores Depuradores Classe B/metabolismo , Esfingosina/análogos & derivados , Transportador 1 de Cassete de Ligação de ATP/antagonistas & inibidores , Transportador 1 de Cassete de Ligação de ATP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Apolipoproteína A-I/metabolismo , Relação Dose-Resposta a Droga , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores Depuradores Classe B/antagonistas & inibidores , Receptores Depuradores Classe B/genética , Transdução de Sinais , Esfingosina/metabolismoRESUMO
High-density lipoprotein (HDL) is a comparatively dense and small lipoprotein that can carry lipids as a multifunctional aggregate in plasma. Several studies have shown that increasing the levels or improving the functionality of HDL is a promising target for treating a wide variety of diseases. Among lipoproteins, HDL particles possess unique physicochemical properties, including naturally synthesized physiological components, amphipathic apolipoproteins, lipid-loading and hydrophobic agent-incorporating characteristics, specific protein-protein interactions, heterogeneity, nanoparticles, and smaller size. Recently, the feasibility and superiority of using HDL particles as drug delivery vehicles have been of great interest. In this review, we summarize the structure, constituents, biogenesis, remodeling, and reconstitution of HDL drug delivery systems, focusing on their delivery capability, characteristics, applications, manufacturing, and drug-loading and drug-targeting characteristics. Finally, the future prospects are presented regarding the clinical application and challenges of using HDL as a pharmacodelivery carrier.
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Sistemas de Liberação de Medicamentos/métodos , Lipoproteínas HDL/metabolismo , Animais , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas HDL/administração & dosagem , Lipoproteínas HDL/biossíntese , Lipoproteínas HDL/química , NanopartículasRESUMO
Numerous studies have reported the presence of oxidized LDL (ox-LDL) and expression of its lectin-like receptor, LOX-1, have been shown in atherosclerotic regions. The present study aims to investigate the effects of ox-LDL on expression of desmoglein 1 (DSG1) and desmocollin 2 (DSC2) in endothelial cells, and to explore the role of LOX-1 mediated signal in the permeability injury associated with DSG1 and DSC2 disruption induced by oxidized lipoprotein. RT-PCR and Western blotting were applied to determine the mRNA and protein expression levels of DSG1 and DSC2 in human umbilical vein endothelial cells (HUVECs) respectively. Immunoreactivities of DSG1 and DSC2 were detected by laser scanning confocal microscope (LSCM). HUVEC monolayers permeability was evaluated by FITC-labeled LDL in transwell assay system. The possible signal was assessed using in vitro blocking LOX-1 or Ca(2+) channel or PKC. The DSG1 and DSC2 expression were decreased by ox-LDL in concentration- and time-dependent manner. The effects of ox-LDL were mediated by its endothelial receptor, LOX-1. In parallel experiments, ox-LDL increased the influx of extracellular calcium, activation of protein kinase C (PKC) and permeability to LDL, which was inhibited by the LOX-1blocking antibody (10 µg/ml), Ca(2+) channel blocker (Diltiazem, 50 µmol/L) and PKC-ß inhibitor (hispidin, 4 µmol/L). These results suggested that ox-LDL-induced decrease in DSG1 and DSC2 expression and monolayer barrier injury via calcium uptake and PKC-ß activation following up-regulation of LOX-1 is one of the mechanisms of inducing greater permeability in HUVECs.
Assuntos
Desmocolinas/genética , Desmogleína 1/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Lipoproteínas LDL/metabolismo , Proteína Quinase C beta/metabolismo , Receptores Depuradores Classe E/metabolismo , Cálcio/metabolismo , Permeabilidade Capilar , Desmossomos/metabolismo , Regulação para Baixo , Humanos , Transdução de SinaisRESUMO
Apolipoprotein M (ApoM) is a novel apolipoprotein that was discovered in 1999 and is bound primarily to high-density lipoproteins (HDLs) in the plasma. Multiple factors may influence its expression at both the post-transcriptional and the transcriptional levels both in vivo and ex vivo as follows: hepatocyte nuclear factor-1α, 4α (HNF-1α, 4α), liver receptor homolog-1 (LRH-1), forkhead box A2 (Foxa2) and platelet activating factor (PAF) upregulate its expression; liver X receptor (LXR), retinoid X receptor (RXR), farnesoid X receptor (FXR), small heterodimer partner (SHP) and the majority of cytokines downregulate its expression. However, mechanisms underlying these processes remain unknown. Structurally, there exists a characterized hydrophobic binding pocket within the apoM protein, which enables it to bind functional lipids such as Sphingosine-1-Phosphate (S1P). Functionally, it facilitates the formation of preß-HDL and enhances an avalanche of atheroprotective effects exerted by HDL. Moreover, in patients with diabetes, the levels of plasma apoM may decrease, whereas the augmentation of apoM decreases plasma glucose levels and magnifies the secretion of insulin. This article offers a panorama of the progress made in the research regarding the characteristics of apoM, particularly the regulation of its expression and its functions.
Assuntos
Apolipoproteínas/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Lipocalinas/sangue , Animais , Apolipoproteínas M , Biomarcadores/sangue , Fator 1-alfa Nuclear de Hepatócito/sangue , Lipoproteínas de Alta Densidade Pré-beta/sangue , Humanos , Lipoproteínas HDL/sangue , Lisofosfolipídeos/sangue , Esfingosina/análogos & derivados , Esfingosina/sangueRESUMO
The X-box binding protein 1 (XBP1) is not only an important component of the unfolded protein response (UPR), but also an important nuclear transcription factor. Upon endoplasmic reticulum stress, XBP1 is spliced by inositol-requiring enzyme 1 (IRE1), thereby generating functional spliced XBP1 (XBP1s). XBP1s functions by translocating into the nucleus to initiate transcriptional programs that regulate a subset of UPR- and non-UPR-associated genes involved in the pathophysiological processes of various diseases. Recent reports have implicated XBP1 in metabolic diseases. This review summarizes the effects of XBP1-mediated regulation on lipid metabolism, glucose metabolism, obesity, and atherosclerosis. Additionally, for the first time, we present XBP1s-dependent transcriptional reprogramming in metabolic diseases under different conditions, including pathology and physiology. Understanding the function of XBP1 in metabolic diseases may provide a basic knowledge for the development of novel therapeutic targets for ameliorating these diseases.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Endorribonucleases/metabolismo , Obesidade/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Animais , Doenças Cardiovasculares/metabolismo , Estresse do Retículo Endoplasmático , Regulação da Expressão Gênica , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos , Fatores de Transcrição de Fator Regulador X , Transcrição Gênica , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-BoxRESUMO
High-density lipoprotein (HDL) has a significant cardioprotective effects. HDL induces cyclooxygenase-2 (COX-2) expression and prostacyclin I-2 (PGI-2) release in vascular endothelial cells, which contributes to its anti-atherogenic effects. However, the underlying mechanisms are not fully understood. In the present study, we observed that HDL-stimulated COX-2 expression and PGI-2 production in human umbilical vein endothelial cells (HUVECs) in a time- and dose-dependent manner. These effects triggered by HDL were inhibited by pertussis toxin (PTX), protein kinase C (PKC) inhibitor GF109203X, and ERK inhibitor PD98059, suggesting that Gαi/Gαo-coupled GPCR, PKC, and ERK pathways are involved in HDL-induced COX-2/PGI-2 activation. More importantly, we found that silencing of sphingosine kinase 2 (SphK-2) also blocked HDL-induced COX-2/PGI-2 activation. In addition, HDL-activated SphK-2 phosphorylation accompanied by increased S1P level in the nucleus. Our ChIP data demonstrated that SphK-2 is associated with CREB at the COX-2 promoter region. Collectively, these results indicate that HDL induces COX-2 expression and PGI-2 release in endothelial cells through activation of PKC, ERK1/2, and SphK-2 pathways. These findings implicate a novel mechanism underlying anti-atherothrombotic effects of HDL.
Assuntos
Ciclo-Oxigenase 2/metabolismo , Células Endoteliais/metabolismo , Epoprostenol/metabolismo , Lipoproteínas HDL/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Células Cultivadas , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/fisiologia , Proteína Quinase C/metabolismo , Receptores Acoplados a Proteínas G/metabolismoRESUMO
PURPOSE: To study the clinical results of XIVE implants placed immediately after sinus floor elevation using osteotomes without bone grafting. METHODS: Totally 14 XIVE implants were placed in 8 patients immediately after sinus floor elevation using osteotomes without bone grafting. The survival rates of the implants during the prosthodontic process and six months after the crowns fabricated were recorded and analyzed. RESULTS: One implant was loosen and extracted during the prosthodontic process and no implant failed six months after the crowns were placed. The survival rate of the implants in this study was 92.9%. CONCLUSIONS: Implants placed immediately after sinus floor elevation using osteotomes without bone grafting could achieve higher survival rates, which is similar to the reported survival rates in dental implants with bone grafting.
Assuntos
Seio Maxilar , Levantamento do Assoalho do Seio Maxilar , Perda do Osso Alveolar , Transplante Ósseo , Coroas , Implantes Dentários , Falha de Restauração Dentária , Humanos , Maxila , Osteotomia , Resultado do TratamentoRESUMO
Plasma concentrations of high-density lipoprotein cholesterol (HDL-C) are strongly and inversely associated with cardiovascular risk. HDL is not a simple lipid transporter, but possesses multiple anti-atherosclerosis activities because it contains special proteins, signaling lipid, and microRNAs. Natural or recombinant HDLs have emerged as potential carriers for delivering a drug to a specified target. However, HDL function also depends on enzymes that alter its structure and composition, as well as cellular receptors and membrane micro-domains that facilitate interactions with the microenvironment. In this review, four mechanisms predicted to enhance functions or targeted therapy of HDL in vivo are discussed. The first involves caveolae-mediated recruitment of HDL signal to bind their receptors. The second involves scavenger receptor class B type I (SR-BI) mediating anchoring and fluidity for signal-lipid of HDL. The third involves lecithin-cholesterol acyltransferase (LCAT) concentrating the signaling lipid at the surface of the HDL particle. The fourth involves microRNAs (miRNAs) being delivered in the blood to special targets by HDL. Exploitation of these four mechanisms will promote HDL to carry targeted drugs and increase HDL's clinical value.
Assuntos
HDL-Colesterol/metabolismo , Portadores de Fármacos/metabolismo , Terapia de Alvo Molecular , Transporte Biológico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Cavéolas/metabolismo , HDL-Colesterol/química , Portadores de Fármacos/química , Drogas em Investigação/metabolismo , Drogas em Investigação/farmacologia , Humanos , Lipoproteínas HDL/metabolismo , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Medicamentos sob Prescrição/metabolismo , Medicamentos sob Prescrição/farmacologia , Receptores de Lipoproteínas/metabolismo , Receptores Depuradores Classe B/metabolismo , Transdução de SinaisRESUMO
AIMS AND OBJECTIVES: The purpose of this study was to describe knowledge about stroke warning signs and risk factors in patients with previous stroke or transient ischaemic attacks in China and to investigate the relationship between socio-demographic characteristics & health status and patients' knowledge about stroke. BACKGROUND: Stroke is the leading cause of death and functional impairment in China. Survivors are at high risk of new vascular events. Secondary prevention after stroke or transient ischaemic attacks is not satisfactory. Previous research suggests that awareness of stroke plays an important role in facilitating secondary prevention. However, little is known about knowledge of stroke warning signs and risk factors among patients with previous stroke/transient ischaemic attacks. DESIGN: A cross-sectional questionnaire study. METHODS: This study was conducted in Hunan Province, China, between July and December in 2010. Subjects were recruited using a cluster sampling method. A questionnaire was administered to 1600 patients with stroke/transient ischaemic attacks diagnose from eight hospitals, and 1200 patients (75%) responded. Patients' knowledge about stroke warning signs and risk factors were collected and analysed. Results. Patients' knowledge about stroke warning signs was very poor (only 3.3% identified all warning signs and 28.3% identified three). Patients' knowledge about important risk factors (e.g. atrial fibrillation, diabetes, metabolic syndrome, etc.) was also very poor (<30%). Patients' action in emergency was extremely poor (only 9.2% reported to call emergency service). The age, education, stroke-related diagnoses and family history of cardiovascular disease were significantly associated with patients' knowledge about stroke. CONCLUSIONS: Knowledge about stroke warning signs and risk factors was very poor in patients with previous stroke or transient ischaemic attacks in China. RELEVANCE TO CLINICAL PRACTICE: Dissemination of stroke knowledge should be a core responsibility for Chinese clinical nurse. Future clinical education to improve patient's knowledge about stroke and further intervention to manage cardiovascular risk factors are indicated.