RESUMO
BACKGROUND/AIMS: Gastric cancer (GC) ranks among the prevalent types of cancer, and its progression is influenced by the tumor microenvironment (TME). A comprehensive comprehension of the TME associated with GC has the potential to unveil therapeutic targets of significance. METHODS: The complexity and heterogeneity of TME interactions were revealed through our investigation using an integrated analysis of single-cell and bulk-tissue sequencing data. RESULTS: We constructed a single-cell transcriptomic atlas of 150,913 cells isolated from GC patients. Our analysis revealed the intricate nature and heterogeneity of the GC TME and the metabolic properties of major cell types. Furthermore, two cell subtypes, LOX+ Fibroblasts and M2 Macrophages, were enriched in tumor tissue and related to the outcome of GC patients. In addition, LOX+ Fibroblasts were significantly associated with M2 macrophages. immunofluorescence double labeling indicated LOX+ Fibroblasts and M2 Macrophages were tightly localized in GC tissue. The two cell subpopulations strongly interacted in a hypoxic microenvironment, yielding an immunosuppressive phenotype. Our findings further suggest that LOX+ Fibroblasts may act as a trigger for inducing the differentiation of monocytes into M2 Macrophages via the IL6-IL6R signaling pathway. CONCLUSIONS: Our study revealed the intricate and interdependent communication network between the fibroblast and macrophage subpopulations, which could offer valuable insights for targeted manipulation of the tumor microenvironment.
Assuntos
Fibroblastos , Macrófagos , Análise de Célula Única , Neoplasias Gástricas , Microambiente Tumoral , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Humanos , Microambiente Tumoral/imunologia , Análise de Célula Única/métodos , Macrófagos/metabolismo , Macrófagos/imunologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genética , Comunicação Celular/imunologia , Proteína-Lisina 6-Oxidase/metabolismo , Proteína-Lisina 6-Oxidase/genética , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Transcriptoma , Transdução de SinaisRESUMO
Several lines of evidence have linked the intestinal bacterium Helicobacter cinaedi with the pathogenesis of atherosclerosis, identifying the Cinaedi Antigen Inflammatory Protein (CAIP) as a key virulence factor. Oxidative stress and inflammation are crucial in sustaining the atherosclerotic process and oxidized LDL (oxLDL) uptake. Primary human macrophages and endothelial cells were pre-incubated with 10 µM diphenyl iodonium salt (DPI) and stimulated with 20 µg/mL CAIP. Lectin-like oxLDL receptor (LOX-1) expression was evaluated by FACS analysis, reactive oxygen species (ROS) production was measured using the fluorescent probe H2DCF-DA, and cytokine release was quantified by ELISA assay. Foam cells formation was assessed by Oil Red-O staining, and phosphorylation of p38 and ERK1/2 MAP kinases and NF-κB pathway activation were determined by Western blot. This study demonstrated that CAIP triggered LOX-1 over-expression and increased ROS production in both macrophages and endothelial cells. Blocking ROS abrogated LOX-1 expression and reduced LDL uptake and foam cells formation. Additionally, CAIP-mediated pro-inflammatory cytokine release was significantly affected by ROS inhibition. The signaling pathway induced by CAIP-induced oxidative stress led to p38 MAP kinase phosphorylation and NF-κB activation. These findings elucidate the mechanism of action of CAIP, which heightens oxidative stress and contributes to the atherosclerotic process in H. cinaedi-infected patients.
Assuntos
Aterosclerose , Infecções por Helicobacter , Helicobacter , Lipoproteínas LDL , Macrófagos , Espécies Reativas de Oxigênio , Receptores Depuradores Classe E , Humanos , Espécies Reativas de Oxigênio/metabolismo , Aterosclerose/metabolismo , Aterosclerose/microbiologia , Aterosclerose/patologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Receptores Depuradores Classe E/metabolismo , Lipoproteínas LDL/metabolismo , Helicobacter/patogenicidade , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , NF-kappa B/metabolismo , Células Espumosas/metabolismo , Citocinas/metabolismo , Estresse Oxidativo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas de Bactérias/metabolismo , Sistema de Sinalização das MAP Quinases , Células Cultivadas , Transdução de SinaisRESUMO
BACKGROUND: The senescence marker p16INK4a, which constitutes part of the genome 9p21.3 cardiovascular disease (CVD) risk allele, is believed to play a role in foam cells formation. This study aims to unravel the role of p16INK4a in mediating macrophage foam cells formation, cellular senescence, and autophagy lysosomal functions. METHODS: The mammalian expression plasmid pCMV-p16INK4a was used to induce p16INK4a overexpression in THP-1 macrophages. Next, wild-type and p16INK4a-overexpressed macrophages were incubated with oxidized LDL to induce foam cells formation. Lipids accumulation was evaluated using Oil-red-O staining and cholesterol efflux assay, as well as expression of scavenger receptors CD36 and LOX-1. Cellular senescence in macrophage foam cells were determined through analysis of senescence-associated ß-galactosidase activity and other SASP factors expression. Meanwhile, autophagy induction was assessed through detection of autophagosome formation and LC3B/p62 markers expression. RESULTS: The findings showed that p16INK4a enhanced foam cells formation with increased scavenger receptors CD36 and LOX-1 expression and reduced cholesterol efflux in THP-1 macrophages. Besides, ß-galactosidase activity was enhanced, and SASP factors such as IL-1α, TNF-α, and MMP9 were up-regulated. In addition, p16INK4a is also shown to induce autophagy, as well as increasing autophagy markers LC3B and p62 expression. CONCLUSIONS: This study provides insights on p16INK4a in mediating macrophages foam cells formation, cellular senescence, and foam cells formation.
Assuntos
Autofagia , Antígenos CD36 , Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina , Células Espumosas , Lipoproteínas LDL , Humanos , Células Espumosas/metabolismo , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Autofagia/genética , Células THP-1 , Antígenos CD36/metabolismo , Antígenos CD36/genética , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Colesterol/metabolismo , Biomarcadores/metabolismo , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genéticaRESUMO
Atherosclerosis is a chronic inflammatory disease that involves modified low-density lipoproteins (LDL) which play a pivotal role in the initiation and progression of the disease. Myeloperoxidase oxidized LDL (Mox-LDL) is considered to be the most patho-physiologically relevant type of modified LDL and has been reported to be ubiquitously present in atheroma plaques of patients with atherosclerosis. Besides its involvement in the latter disease state, Mox-LDL has also been shown to be implicated in the pathogenesis of various illnesses including sleep disorders, which are in turn associated with heart disease and depression in many intricate ways. Meanwhile, we have recently shown that lox-1-mediated Mox-LDL signaling modulates neuroserpin activity in endothelial cells, which could have major implications that go beyond the pathophysiology of stroke and cerebrovascular disease (CD). Of note is that tissue plasminogen activator (tPA), which is the main target of neuroserpin in the brain, has a crucial function in the processing of brain-derived neurotrophic factor (BDNF) into its mature form. This factor is known to be involved in major depressive disorder (MDD) development and pathogenesis. Since tPA is more conventionally recognized as being involved in fibrinolytic mechanisms, and its effect on the BDNF system in the context of MDD is still not extensively studied, we speculate that any Mox-LDL-driven change in the activity of tPA in patients with atherosclerosis may lead to a decrease in the production of mature BDNF, resulting in impaired neural plasticity and depression. Deciphering the mechanisms of interaction between those factors could help in better understanding the potentially overlapping pathological mechanisms that regulate disease processes in CD and MDD, supporting the possibility of novel and common therapeutic opportunities for millions of patients worldwide.
Assuntos
Aterosclerose , Lipoproteínas LDL , Peroxidase , Humanos , Aterosclerose/metabolismo , Lipoproteínas LDL/metabolismo , Peroxidase/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/metabolismo , Neuroserpina , Receptores Depuradores Classe E/metabolismo , Transtorno Depressivo Maior/metabolismoRESUMO
BACKGROUND: Lipid metabolism disorders are associated with degeneration of multiple tissues and organs, but the mechanism of crosstalk between lipid metabolism disorder and intervertebral disc degeneration (IDD) has not been fully elucidated. In this study we aim to investigate the regulatory mechanism of abnormal signal of lipid metabolism disorder on intervertebral disc endplate chondrocyte (EPC) senescence and calcification. METHODS: Human intervertebral disc cartilage endplate tissue, cell model and rat hyperlipemia model were performed in this study. Histology and immunohistochemistry were used to human EPC tissue detection. TMT-labelled quantitative proteomics was used to detect differential proteins, and MRI, micro-CT, safranin green staining and immunofluorescence were performed to observe the morphology and degeneration of rat tail intervertebral discs. Flow cytometry, senescence-associated ß-galactosidase staining, alizarin red staining, alkaline phosphatase staining, DCFH-DA fluorescent probe, and western blot were performed to detect the expression of EPC cell senescence, senescence-associated secretory phenotype, calcification-related proteins and the activation of cell senescence-related signaling pathways. RESULTS: Our study found that the highly expressed oxidized low-density lipoprotein (ox-LDL) and Lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) in human degenerative EPC was associated with hyperlipidemia (HLP). TMT-labelled quantitative proteomics revealed enriched pathways such as cell cycle regulation, endochondral bone morphogenesis and inflammation. The rat model revealed that HLP could induce ox-LDL, LOX-1, senescence and calcification markers high expression in EPC. Moreover, we demonstrated that ox-LDL-induced EPCs senescence and calcification were dependent on the LOX-1 receptor, and the ROS/P38-MAPK/NF-κB signaling pathway was implicated in the regulation of senescence induced by ox-LDL/LOX-1 in cell model. CONCLUSIONS: So our study revealed that ox-LDL/LOX-1-induced EPCs senescence and calcification through ROS/P38-MAPK/NF-κB signaling pathway, providing information on understanding the link between lipid metabolism disorders and IDD.
Assuntos
Senescência Celular , Condrócitos , Degeneração do Disco Intervertebral , Metabolismo dos Lipídeos , Lipoproteínas LDL , Receptores Depuradores Classe E , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Lipoproteínas LDL/metabolismo , Animais , Humanos , Receptores Depuradores Classe E/metabolismo , Condrócitos/metabolismo , Condrócitos/patologia , Ratos , Masculino , Calcinose/metabolismo , Calcinose/patologia , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Modelos Animais de Doenças , Feminino , Pessoa de Meia-Idade , Transdução de Sinais , Adulto , Proteômica/métodos , Ratos Sprague-DawleyRESUMO
PURPOSE: Aspergillus fumigatus (A. fumigatus) keratitis is a type of infectious corneal disease that significantly impairs vision. The objective of this study is to evaluate the therapeutic potential of chelerythrine (CHE) on A. fumigatus keratitis. METHODS: The antifungal activity of CHE was assessed through various tests including the minimum inhibitory concentration test, scanning electron microscopy, transmission electron microscopy, propidium iodide uptake test and plate count. Neutrophil infiltration and activity were assessed using immunofluorescence staining and the myeloperoxidase test. RT-PCR, western blotting assay, and ELISA were performed to measure the expression levels of proinflammatory cytokines (IL-1ß and IL-6), NF-E2-related factor (Nrf2), heme oxygenase-1 (HO-1), and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), as well as to determine the ratio of phosphorylated-p38 (p-p38) mitogen-activated protein kinase (MAPK) to p38 MAPK. RESULTS: In vitro, CHE inhibited the growth of A. fumigatus conidia, reduced fungal hyphae survival, and prevented fungal biofilm formation. In vivo, CHE reduced the severity of A. fumigatus keratitis and exhibited an excellent anti-inflammatory effect by blocking neutrophil infiltration. Furthermore, CHE decreased the expression levels of proinflammatory cytokines and LOX-1 at both mRNA and protein levels, while also decreasing the p-p38 MAPK/p38 MAPK ratio. Additionally, CHE increased the expression levels of Nrf2 and HO-1. CONCLUSION: CHE provides protection against A. fumigatus keratitis through multiple mechanisms, including reducing fungal survival, inducing anti-inflammatory effects, enhancing Nrf2 and HO-1 expression, and suppressing the signaling pathway of LOX-1/p38 MAPK.
Assuntos
Aspergilose , Aspergillus fumigatus , Benzofenantridinas , Ceratite , Fator 2 Relacionado a NF-E2 , Receptores Depuradores Classe E , Proteínas Quinases p38 Ativadas por Mitógeno , Aspergillus fumigatus/efeitos dos fármacos , Receptores Depuradores Classe E/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ceratite/microbiologia , Ceratite/tratamento farmacológico , Ceratite/metabolismo , Animais , Benzofenantridinas/farmacologia , Benzofenantridinas/uso terapêutico , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Heme Oxigenase-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Feminino , Citocinas/metabolismoRESUMO
Background: Lysyl oxidase enzymes (LOXs), as extracellular matrix (ECM) protein regulators, play vital roles in tumor progression by remodeling the tumor microenvironment. However, their roles in glioblastoma (GBM) have not been fully elucidated. Methods: The genetic alterations and prognostic value of LOXs were investigated via cBioPortal. The correlations between LOXs and biological functions/molecular tumor subtypes were explored in The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA). After KaplanâMeier and Cox survival analyses, a Loxl1-based nomogram and prognostic risk score model (PRSM) were constructed and evaluated by time-dependent receiver operating characteristic curves, calibration curves, and decision curve analyses. Tumor enrichment pathways and immune infiltrates were explored by single-cell RNA sequencing and TIMER. Loxl1-related changes in tumor viability/proliferation and invasion were further validated by CCK-8, western blot, wound healing, and Transwell invasion assays. Results: GBM patients with altered LOXs had poor survival. Upregulated LOXs were found in IDH1-wildtype and mesenchymal (not Loxl1) GBM subtypes, promoting ECM receptor interactions in GBM. The Loxl1-based nomogram and the PRSM showed high accuracy, reliability, and net clinical benefits. Loxl1 expression was related to tumor invasion and immune infiltration (B cells, neutrophils, and dendritic cells). Loxl1 knockdown suppressed GBM cell proliferation and invasion by inhibiting the EMT pathway (through the downregulation of N-cadherin/Vimentin/Snai1 and the upregulation of E-cadherin). Conclusion: The Loxl1-based nomogram and PRSM were stable and individualized for assessing GBM patient prognosis, and the invasive role of Loxl1 could provide a promising therapeutic strategy.
Assuntos
Neoplasias Encefálicas , Transição Epitelial-Mesenquimal , Glioblastoma , Invasividade Neoplásica , Humanos , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/mortalidade , Glioblastoma/metabolismo , Transição Epitelial-Mesenquimal/genética , Prognóstico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Nomogramas , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genética , Masculino , Microambiente Tumoral , Feminino , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Proliferação de Células , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Proteína-Lisina 6-Oxidase/metabolismo , Proteína-Lisina 6-Oxidase/genética , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismoRESUMO
Preeclampsia is a hypertensive disorder of pregnancy marked by vascular dysfunction, large artery stiffness, and excess oxidized low-density lipoprotein (oxLDL). oxLDL activates oxidative stress pathways which contribute to arterial stiffness through interaction with the lectin-like oxLDL receptor 1 (LOX-1). Increased vascular stiffness is associated with higher pulse wave velocity and downstream microvasculature damage. Here we evaluated the ability of LOX-1 inhibition (LOX-1i) to prevent large artery structural and microvascular structural and functional changes via assessment of the descending thoracic aorta (DTAo) and posterior cerebral arteries (PCA) in a high cholesterol model of preeclampsia. Adult female Sprague Dawley normal late-pregnant (LP) and experimentally preeclamptic (ePE, high cholesterol diet d7-19) animals underwent intraperitoneal (i.p.) implantation of a mini-osmotic pump at d12 containing LOX-1 neutralizing antibodies (ePE + LOX-1i, n = 7) or goat IgG as vehicle control (LP + IgG, n = 8 and ePE + IgG, n = 8). Animals were studied at d19. DTAos and PCAs were removed for histologic assessment and isolated vessel experiments, respectively. Fetuses and placentas were weighed individually. Plasma was analyzed for markers of oxidative stress. ePE + IgG DTAo elastin content (an indirect metric of stiffness) was not significantly different from the LP + IgG group. Nonetheless, trending elastin break and sinuosity data (higher number of breaks and lower sinuosity in the ePE + IgG group compared to LP + IgG) suggested increased stiffness in this high cholesterol PE model. LOX-1i appeared to prevent a decrease in elastin. PCAs showed no structural changes with ePE or LOX-1i. ePE PCAs had increased reactivity to the nitric oxide donor sodium nitroprusside and decreased tone that was unaffected by LOX-1i. ePE animals had increased plasma oxLDL and 3-nitrotyrosine that was unaffected by LOX-1i. Taken together, LOX-1i may improve large artery stiffness without mitigation of the oxidative stress or cerebral microvascular dysfunction seen in ePE. Understanding these mechanisms is important in abating the long-term risks of preeclampsia.
Assuntos
Modelos Animais de Doenças , Artéria Cerebral Posterior , Pré-Eclâmpsia , Ratos Sprague-Dawley , Receptores Depuradores Classe E , Feminino , Gravidez , Animais , Receptores Depuradores Classe E/metabolismo , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Artéria Cerebral Posterior/efeitos dos fármacos , Artéria Cerebral Posterior/metabolismo , Artéria Cerebral Posterior/patologia , Artéria Cerebral Posterior/fisiopatologia , Ratos , Rigidez Vascular/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aorta Torácica/fisiopatologiaAssuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Receptores Depuradores Classe E , Humanos , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/terapia , Neoplasias Bucais/metabolismo , Receptores Depuradores Classe E/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismoRESUMO
LOX-1, ORL-1, or lectin-like oxidized low-density lipoprotein receptor 1 is a transmembrane glycoprotein that binds and internalizes ox-LDL in foam cells. LOX-1 is the main receptor for oxidized low-density lipoproteins (ox-LDL). The LDL comes from food intake and circulates through the bloodstream. LOX-1 belongs to scavenger receptors (SR), which are associated with various cardiovascular diseases. The most important and severe of these is the formation of atherosclerotic plaques in the intimal layer of the endothelium. These plaques can evolve into complicated thrombi with the participation of fibroblasts, activated platelets, apoptotic muscle cells, and macrophages transformed into foam cells. This process causes changes in vascular endothelial homeostasis, leading to partial or total obstruction in the lumen of blood vessels. This obstruction can result in oxygen deprivation to the heart. Recently, LOX-1 has been involved in other pathologies, such as obesity and diabetes mellitus. However, the development of atherosclerosis has been the most relevant due to its relationship with cerebrovascular accidents and heart attacks. In this review, we will summarize findings related to the physiologic and pathophysiological processes of LOX-1 to support the detection, diagnosis, and prevention of those diseases.
Assuntos
Doenças Cardiovasculares , Receptores Depuradores Classe E , Humanos , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genética , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/etiologia , Animais , Lipoproteínas LDL/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologiaRESUMO
A novel optically induced dielectrophoresis (ODEP) system that can operate under flow conditions is designed for automatic trapping of cells and subsequent induction of 2D multi-frequency cell trajectories. Like in a "ping-pong" match, two virtual electrode barriers operate in an alternate mode with varying frequencies of the input voltage. The so-derived cell motions are characterized via time-lapse microscopy, cell tracking, and state-of-the-art machine learning algorithms, like the wavelet scattering transform (WST). As a cell-electrokinetic fingerprint, the dynamic of variation of the cell displacements happening, over time, is quantified in response to different frequency values of the induced electric field. When tested on two biological scenarios in the cancer domain, the proposed approach discriminates cellular dielectric phenotypes obtained, respectively, at different early phases of drug-induced apoptosis in prostate cancer (PC3) cells and for differential expression of the lectine-like oxidized low-density lipoprotein receptor-1 (LOX-1) transcript levels in human colorectal adenocarcinoma (DLD-1) cells. The results demonstrate increased discrimination of the proposed system and pose an additional basis for making ODEP-based assays addressing cancer heterogeneity for precision medicine and pharmacological research.
Assuntos
Eletroforese , Análise de Célula Única , Humanos , Eletroforese/métodos , Linhagem Celular Tumoral , Análise de Célula Única/métodos , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genética , Apoptose/efeitos dos fármacos , Aprendizado de Máquina , MasculinoRESUMO
Lipids play an important role in varying vital cellular processes including cell growth and division. Elevated levels of low-density lipoprotein (LDL) and oxidized-LDL (ox-LDL), and overexpression of the corresponding receptors including LDL receptor (LDLR), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), and cluster of differentiation 36 (CD36), have shown strong correlations with different facets of carcinogenesis including proliferation, invasion, and angiogenesis. Furthermore, a high serum level of LOX-1 is considered as a poor prognostic factor in many types of cancer including colorectal cancer. Ox-LDL could contribute to cancer progression and metastasis through endothelial-to-mesenchymal transition (EMT) and autophagy. Thus, many studies have shed light on the significant role of ox-LDL as a potential therapeutic target for cancer therapy. In various repurposing approaches, anti-dyslipidemia agents, phytochemicals, autophagy modulators as well as recently developed ldl-like nanoparticles have been investigated as potential tumor therapeutic agents by targeting oxidized-LDL/LOX-1 pathways. Herein, we reviewed the role of oxidized-LDL and LOX-1 in cancer progression, invasion, metastasis, and also cancer-associated angiogenesis. Moreover, we addressed therapeutic utility of several compounds that proved to be capable of targeting the metabolic moieties in cancer. This review provides insights on the potential impact of targeting LDL and ox-LDL in cancer therapy and their future biomedical implementations.
Assuntos
Lipoproteínas LDL , Neoplasias , Humanos , Lipoproteínas LDL/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/antagonistas & inibidores , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , AnimaisRESUMO
BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) can initiate and affect almost all atherosclerotic events including endothelial dysfunction. In this text, the role and underlying molecular basis of procyanidin B2 (PCB2) with potential anti-oxidant and anti-inflammatory activities in ox-LDL-induced HUVEC injury were examined. METHODS: HUVECs were treated with ox-LDL in the presence or absence of PCB2. Cell viability and apoptotic rate were examined by CCK-8 assay and flow cytometry, respectively. The mRNA and protein levels of genes were tested by RT-qPCR and western blot assays, respectively. Potential downstream targets and pathways of apple procyanidin oligomers were examined by bioinformatics analysis for the GSE9647 dataset. The effect of PCB2 on THP-1 cell migration was examined by recruitment assay. The effect of PCB2 on oxidative stress was assessed by reactive oxygen species (ROS) level, malondialdehyde (MDA) content, and mitochondrial membrane potential (MMP). RESULTS: ox-LDL reduced cell viability, induced cell apoptosis, and facilitated the expression of oxidized low-density lipoprotein receptor 1 (LOX-1), C-C motif chemokine ligand 2 (MCP-1), vascular cell adhesion protein 1 (VCAM-1) in HUVECs. PCB2 alleviated ox-LDL-induced cell injury in HUVECs. Apple procyanidin oligomers triggered the differential expression of 592 genes in HUVECs (|log2fold-change| > 0.58 and adjusted p-value < 0.05). These dysregulated genes might be implicated in apoptosis, endothelial cell proliferation, inflammation, and monocyte chemotaxis. PCB2 inhibited C-X-C motif chemokine ligand 1/8 (CXCL1/8) expression and THP-1 cell recruitment in ox-LDL-stimulated HUVECs. PCB2 inhibited ox-LDL-induced oxidative stress and nuclear factor kappa-B (NF-κB) activation in HUVECs. CONCLUSION: PCB2 weakened ox-LDL-induced cell injury, inflammation, monocyte recruitment, and oxidative stress by inhibiting the NF-κB pathway in HUVECs.
Assuntos
Anti-Inflamatórios , Apoptose , Biflavonoides , Catequina , Células Endoteliais da Veia Umbilical Humana , Lipoproteínas LDL , NF-kappa B , Estresse Oxidativo , Proantocianidinas , Transdução de Sinais , Humanos , Lipoproteínas LDL/toxicidade , Catequina/farmacologia , Proantocianidinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Biflavonoides/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Transdução de Sinais/efeitos dos fármacos , NF-kappa B/metabolismo , Apoptose/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/patologia , Antioxidantes/farmacologia , Células THP-1 , Quimiotaxia de Leucócito/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genéticaRESUMO
BACKGROUND: Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is known as a major receptor for oxidized low-density lipoproteins (oxLDL) and plays a significant role in the genesis of atherosclerosis. Recent research has shown its involvement in cancer, ischemic stroke, and diabetes. LOX-1 is a C-type lectin receptor and is involved in the activation of immune cells and inflammatory processes. It may further interact with pathogens, suggesting a role in infections or the host's response. SUMMARY: This review compiles the current knowledge of potential implications of LOX-1 in inflammatory processes and in host-pathogen interactions with a particular emphasis on its regulatory role in immune responses. Also discussed are genomic and structural variations found in LOX-1 homologs across different species as well as potential involvements of LOX-1 in inflammatory processes from the angle of different cell types and organ-specific interactions. KEY MESSAGES: The results presented reveal both similar and different structures in human and murine LOX-1 and provide clues as to the possible origins of different modes of interaction. These descriptions raise concerns about the suitability, particularly of mouse models, that are often used in the analysis of its functionality in humans. Further research should also aim to better understand the mostly unknown binding and interaction mechanisms between LOX-1 and different pathogens. This pursuit will not only enhance our understanding of LOX-1 involvement in inflammatory processes but also identify potential targets for immunomodulatory approaches.
Assuntos
Interações Hospedeiro-Patógeno , Inflamação , Receptores Depuradores Classe E , Animais , Humanos , Camundongos , Aterosclerose/imunologia , Aterosclerose/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Inflamação/imunologia , Lipoproteínas LDL/metabolismo , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genéticaRESUMO
Obesity is a significant health concern that leads to impaired vascular function and subsequent abnormalities in various organs. The impact of obesity on ocular blood vessels, however, remains largely unclear. In this study, we examined the hypothesis that obesity induced by high-fat diet produces vascular endothelial dysfunction in the ophthalmic artery. Mice were subjected to a high-fat diet for 20 weeks, while age-matched controls were maintained on a standard diet. Reactivity of isolated ophthalmic artery segments was assessed in vitro. Reactive oxygen species (ROS) were quantified in cryosections by dihydroethidium (DHE) staining. Redox gene expression was determined in ophthalmic artery explants by real-time PCR. Furthermore, the expression of nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2), the receptor for advanced glycation end products (RAGE), and of the lectin-like oxidized low-density-lipoprotein receptor-1 (LOX-1) was determined in cryosections using immunofluorescence microscopy. Ophthalmic artery segments from mice on a high-fat diet exhibited impaired vasodilation responses to the endothelium-dependent vasodilator acetylcholine, while endothelium-independent responses to nitroprusside remained preserved. DHE staining intensity in the vascular wall was notably stronger in mice on a high-fat diet. Messenger RNA expression for NOX2 was elevated in the ophthalmic artery of mice subjected to high fat diet. Likewise, immunostainings revealed increased expression of NOX2 and of RAGE, but not of LOX-1. These findings suggest that a high-fat diet triggers endothelial dysfunction by inducing oxidative stress in the ophthalmic artery via involvement of RAGE and NOX2.
Assuntos
Dieta Hiperlipídica , Artéria Oftálmica , Doenças Vasculares , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Endotélio Vascular/metabolismo , Obesidade , Artéria Oftálmica/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/metabolismo , Doenças Vasculares/metabolismo , VasodilataçãoRESUMO
Low-density lipoprotein (LDL) and oxidized LDL (oxLDL) are major contributors to atherogenesis, as endogenous antigens, via several receptors such as LOX 1. A PubMed search was conducted in order to identify relevant articles regarding LOX-1's role in the atherosclerosis, diagnosis, prognostic use and molecules that could be used for therapy. The references of the manuscripts obtained were also reviewed, in order to find additional relevant bibliography. LOX-1 is a lectin-like pattern recognition receptor, mostly expressed in endothelial cells (ECs) which can bind a variety of molecules, including oxLDL and C-reactive protein (CRP). LOX-1 plays a key role in oxLDL's role as a causative agent of atherosclerosis through several pathologic mechanisms, such as oxLDL deposition in the subintima, foam cell formation and endothelial dysfunction. Additionally, LOX-1 acts a scavenger receptor for oxLDL in macrophages and can be responsible for oxLDL uptake, when stimulated. Serum LOX-1 (sLOX-1) has emerged as a new, potential biomarker for diagnosis of acute coronary syndromes, and it seems promising for use along with other common biomarkers in everyday clinical practice. In a therapeutic perspective, natural as well as synthetic molecules exert anti-LOX-1 properties and attain the receptor's pathophysiological effects, thus extensive research is ongoing to further evaluate molecules with therapeutic potential. However, most of these molecules need further trials in order to properly assess their safety and efficacy for clinical use. The aim of this review is to investigate LOX-1 role in atherogenesis and explore its potential as diagnostic tool and therapeutic target.
Assuntos
Aterosclerose , Células Endoteliais , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Receptores Depuradores Classe E/metabolismo , Aterosclerose/diagnóstico , Aterosclerose/etiologiaRESUMO
Accelerating the repair of damaged endothelium can effectively inhibit the progression of atherosclerosis (AS). Transient receptor potential channel TRPM4 is a non-selective cation channel activated by internal Ca2+, which is expressed in endothelial cells. This study aimed to reveal the potential role of TRPM4 in AS along with the mechanism. Human coronary artery endothelial cells (HCAECs) induced by ox-LDL was regarded as an in vitro model. The impacts of TRPM4 knockdown on cellular inflammation response, oxidative stress, normal endothelial function and lipid peroxidation were evaluated. Given that ferroptosis promotes AS progression, the effects of TRPM4 on intracellular iron ions and ferroptosis-related proteins was determined. Afterwards, HCAECs were treated with ferroptosis inducer erastin, and the influence of ferroptosis in the cellular model was revealed. TRPM4 was elevated in response to ox-LDL treatment in HCAECs. TRPM4 knockdown reduced the inflammation response, oxidative stress and lipid peroxidation caused by ox-LDL, and maintained the normal function of HCAECs. Erastin treatment destroyed the impacts of TRPM4 knockdown that are beneficial for cells to resist ox-LDL, showing the enhancement of the above adverse factors. Together, this study found that TRPM4 knockdown reduced ox-LDL-induced inflammation, oxidative stress, and dysfunction in HCAECs, possibly via a mechanism involving Fe2+ and ferroptosis-related proteins.
Assuntos
Ferroptose , Canais de Cátion TRPM , Humanos , Receptores de LDL/metabolismo , Receptores de LDL Oxidado/metabolismo , Células Endoteliais/metabolismo , Receptores Depuradores Classe E/metabolismo , Células Cultivadas , Lipoproteínas LDL/farmacologia , Lipoproteínas LDL/metabolismo , Vasos Coronários/metabolismo , Proteínas/metabolismo , Inflamação/metabolismo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismoRESUMO
Our previous studies have shown that lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) is expressed in liver sinusoidal endothelial cells, and oxidized low-density lipoprotein induces liver sinusoidal dysfunction and defenestration through the LOX-1/ROS/NF-kB pathway, revealing that LOX-1 can mediate liver sinusoidal barrier function, involved in the regulation of non-alcoholic fatty liver disease. Here, we investigated whether, in the context of bone metabolic diseases, LOX-1 could affect bone quality and type H blood vessels in diabetic mice. We used db/db mice as model and found that LOX-1 knockdown can ameliorate bone quality and type H blood vessel generation in db/db mice. This further verifies our hypothesis that LOX-1 is involved in the regulation of bone quality and type H blood vessel homeostasis, thus inhibiting osteoporosis progression in db/db mice.
Assuntos
Diabetes Mellitus Experimental , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais/metabolismo , Lipoproteínas LDL/metabolismo , NF-kappa B/metabolismo , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/metabolismoRESUMO
The success of Staphylococcus aureus as a major cause for endovascular infections depends on effective interactions with blood-vessel walls. We have previously shown that S. aureus uses its wall teichoic acid (WTA), a surface glycopolymer, to attach to endothelial cells. However, the endothelial WTA receptor remained unknown. We show here that the endothelial oxidized low-density lipoprotein receptor 1 (LOX-1) interacts with S. aureus WTA and permits effective binding of S. aureus to human endothelial cells. Purified LOX-1 bound to isolated S. aureus WTA. Ectopic LOX-1 expression led to increased binding of S. aureus wild type but not of a WTA-deficient mutant to a cell line, and LOX-1 blockage prevented S. aureus binding to endothelial cells. Moreover, WTA and LOX-1 expression levels correlated with the efficacy of the S. aureus-endothelial interaction. Thus, LOX-1 is an endothelial ligand for S. aureus, whose blockage may help to prevent or treat severe endovascular infections.
Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Células Endoteliais , Ácidos Teicoicos/metabolismo , Receptores Depuradores/metabolismo , Receptores Depuradores Classe E/genética , Receptores Depuradores Classe E/metabolismoRESUMO
OBJECTIVE: Diabetic kidney disease (DKD) is characterized by the abnormal deposition of oxidized low-density lipoprotein (ox-LDL), which contributes to podocyte damage. Klotho, an aging suppressor that plays a critical role in protecting podocytes in DKD, is mainly expressed in kidney tubular epithelium and secreted in the blood. However, it has not been established whether Klotho can alleviate podocyte injury by inhibiting renal ox-LDL deposition, and the potential molecular mechanisms require further investigation. METHODS: We conducted a comprehensive analysis of serum and kidney biopsy samples obtained from patients diagnosed with DKD. Additionally, to explore the underlying mechanism of Klotho in the deposition of ox-LDL in the kidneys, we employed a mouse model of DKD with the Klotho genotype induced by streptozotocin (STZ). Furthermore, we conducted meticulous in vitro experiments on podocytes to gain further insights into the specific role of Klotho in the deposition of ox-LDL within the kidney. RESULTS: Our groundbreaking study unveiled the remarkable ability of the soluble form of Klotho to effectively inhibit high glucose-induced ox-LDL deposition in podocytes affected by DKD. Subsequent investigations elucidated that Klotho achieved this inhibition by reducing the expression of the insulin/insulin-like growth factor 1 receptor (IGF-1R), consequently leading to a decrease in the expression of Ras-related C3 botulinum toxin substrate 1 (RAC1) and an enhancement of mitochondrial function. Ultimately, this series of events culminated in a significant reduction in the expression of the oxidized low-density lipoprotein receptor (OLR1), thereby resulting in a notable decrease in renal ox-LDL deposition in DKD. CONCLUSION: Our findings suggested that Klotho had the potential to mitigate podocyte injury and reduced high glucose-induced ox-LDL deposition in glomerulus by modulating the IGF-1R/RAC1/OLR1 signaling. These results provided valuable insights that could inform the development of novel strategies for diagnosing and treating DKD.