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1.
AME Case Rep ; 8: 27, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38234354

RESUMEN

Background: With the widespread application of metagenomic next-generation sequencing (mNGS) in pathogen detection, the reports of severe Chlamydia psittaci (C. psittaci) pneumonia are increasing. It is essential to determine the best management of severe C. psittaci pneumonia. Case Description: This report describes a 51-year-old male patient who presented with symptoms of expectoration, relative bradycardia, and dyspnea. Lung computed tomography (CT) on day 1 (D1) showed consolidation of the left lower lobe. He was intubated and transferred to the intensive care unit (ICU). The symptoms of high fever and progressive dyspnea [the lowest level of arterial partial pressure of oxygen/fractional inspired oxygen (PaO2/FiO2): 52 mmHg] persisted on D3. Meanwhile, he produced a large volume of golden-yellow, watery sputum, due to which endotracheal suction was repeatedly performed to maintain patency of the airway. The repeat radiography showed extensive deterioration of diffuse exudation in bilateral lobes. An early treatment with methylprednisolone was initiated on D3, after which the watery sputum decreased and turned viscous. The mNGS of the bronchoalveolar lavage fluid (BALF) identified C. psittaci on D7, and combined targeted antimicrobial therapy (azithromycin and doxycycline) was subsequently initiated. After 1 week of treatment, the patient was extubated on D14. He was transferred to the respiratory department on D17 and discharged on D25 with oral medications (azithromycin and doxycycline for 2 weeks). The repeat chest CT on D68 showed that the bilateral exudation and left lower lobe consolidation had almost disappeared, without pleural effusion. Conclusions: In severe C. psittaci pneumonia, although the presentations differ, the rapid pathogen identification through BALF mNGS may facilitate the early use of effective antibiotics. Timely and comprehensive treatment is important for improving outcomes in severe C. psittaci pneumonia.

2.
Lipids Health Dis ; 22(1): 86, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37386457

RESUMEN

BACKGROUND: The previous study investigated whether the functions of small, medium, and large high density lipoprotein (S/M/L-HDL) are correlated with protein changes in mice. Herein, the proteomic and functional analyses of high density lipoprotein (HDL) subclasses were performed in humans and rats. METHODS: After purifying S/M/L-HDL subclasses from healthy humans (n = 6) and rats (n = 3) using fast protein liquid chromatography (FPLC) with calcium silica hydrate (CSH) resin, the proteomic analysis by mass spectrometry was conducted, as well as the capacities of cholesterol efflux and antioxidation was measured. RESULTS: Of the 120 and 106 HDL proteins identified, 85 and 68 proteins were significantly changed in concentration among the S/M/L-HDL subclasses in humans and rats, respectively. Interestingly, it was found that the relatively abundant proteins in the small HDL (S-HDL) and large HDL (L-HDL) subclasses did not overlap, both in humans and in rats. Next, by searching for the biological functions of the relatively abundant proteins in the HDL subclasses via Gene Ontology, it was displayed that the relatively abundant proteins involved in lipid metabolism and antioxidation were enriched more in the medium HDL (M-HDL) subclass than in the S/L-HDL subclasses in humans, whereas in rats, the relatively abundant proteins associated with lipid metabolism and anti-oxidation were enriched in M/L-HDL and S/M-HDL, respectively. Finally, it was confirmed that M-HDL and L-HDL had the highest cholesterol efflux capacity among the three HDL subclasses in humans and rats, respectively; moreover, M-HDL exhibited higher antioxidative capacity than S-HDL in both humans and rats. CONCLUSIONS: The S-HDL and L-HDL subclasses are likely to have different proteomic components during HDL maturation, and results from the proteomics-based comparison of the HDL subclasses may explain the associated differences in function.


Asunto(s)
Antioxidantes , Proteómica , Humanos , Ratas , Ratones , Animales , Prueba de Estudio Conceptual , Lipoproteínas HDL , Colesterol
3.
Ann Transl Med ; 10(14): 763, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35965831

RESUMEN

Background: The incidence of deep venous thrombosis (DVT) is higher in surgical patients, but there have been few studies on the risk factors of DVT in intensive care unit (ICU) patients after oral cancer surgery, particularly in relation to the inflammatory and nutritional scores, and intervene with these risk factors early may decrease the occurrence of DVT. Methods: We performed a retrospective study of adult patients who were admitted to ICU after undergoing radical resection of oral cancer and performed ultrasound detection for DVT within 1 week after surgery from April 2019 to July 2021. DVT was diagnosed by venous ultrasonography of the lower extremities. Preoperative inflammatory and nutritional scores, including neutrophil to lymphocyte ratio (NLR), plate to lymphocyte ratio (PLR), prognostic nutritional index (PNI) were retrospectively calculated according to test results before surgery. Clinical characteristics, including the Acute Physiology and Chronic Health Evaluation II (APACHE II) score, Caprini Risk Score (CRS), Charlson comorbidity index, anticoagulation therapy, and mechanical ventilation time (MVT) after admitted to ICU were obtained. The risk factors affecting DVT occurrence were analyzed by logistic regression, and the receiver operating characteristic (ROC) curve was used to analyze the value of the relevant indicators in evaluating DVT. Results: Among the 128 patients, 43 patients (33.6%) developed DVT. Compared with the non-DVT group, the preoperative glucose (GLU), postoperative D-dimer (P<0.05), and postoperative NLR (P<0.001) were higher in the DVT group than in the non-DVT group. In multivariate logistic analysis, NLR (P=0.001), postoperative D-dimer >5.57 µg/mL (P=0.002), GLU >5.15 mmol/L (P=0.025) was associated with DVT, and the areas under the curve (AUCs) of NLR in predicting DVT was 0.729. We also found that the DVT group had longer MVT and length of stay (LOS) than the non-DVT group, and correlation analysis indicated that NLR level was positively related with MVT (r=0.36; P<0.0001) and LOS (r=0.452; P<0.0001). Conclusions: A high level of NLR, indicative of a poor immunity and nutrition status, increases the risk of DVT in patients after oral cancer surgery, and improvement of immunity and nutrition status may help decrease the occurrence of postoperative DVT.

4.
Cell Mol Biol (Noisy-le-grand) ; 67(5): 405-420, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35818227

RESUMEN

Sepsis has been recognized to be a life-threatening organ dysfunction caused by the dysregulation of the host response to infections. Our work aims to screen key biomarkers related to neutrophils in sepsis using bioinformatics analysis. For this purpose, the microarray datasets related to neutrophils in sepsis patients were downloaded from the Gene Expression Omnibus (GEO) database. According to the Bayesian test, the Limma package in R was used to screen differentially expressed genes (DEGs). Then, DEGs were uploaded to the DAVID online diagnostic tool for subsequent Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment on the selected DEGs. Next, protein-protein interaction (PPI) network was established based on the selected DEGs using the STRING website and the Cytoscape software. Furthermore, according to the function of the iRegulon plug-in in Cytoscape, our study further predicts and established regulatory networks related to transcription factors and regulatory genes. In addition, the miRWalk2.0 database was used to search for miRNA-DEG pairs, associated with the conduction of intersections of miRNAs predicted by TargetScan, Miranda, miRDB and RNA22 databases. Then, these miRNA-DEG pairs were also displayed in the form of a regulatory network through Cytoscape. Finally, two datasets were selected to verify the screened genes, regulatory factors, and miRNAs, to plot receiver operating characteristics (ROC) curves and compute the area under the curve (AUC) values. The results showed that AKT1, MMP9, ARG1, ETS1 targeting AKT1, and has-miR-124-3p targeting RPS6KA5 may have diagnostic value for patients with sepsis and septic shock. While further experimental studies are required to confirm their role in septic neutrophils.


Asunto(s)
MicroARNs , Sepsis , Teorema de Bayes , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes , Humanos , MicroARNs/genética , Neutrófilos , Mapas de Interacción de Proteínas/genética , Sepsis/genética , Factores de Transcripción/genética
5.
Cardiovasc Drugs Ther ; 36(4): 665-678, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33740174

RESUMEN

PURPOSE: Intracellular cholesterol imbalance plays an important role in adipocyte dysfunction of obesity. However, it is unclear whether obesity induced monocyte chemoattractant protein-1 (MCP-1) causes the adipocyte cholesterol imbalance. In this study, we hypothesize that MCP-1 impairs cholesterol efflux of adipocytes to HDL2 and insulin rescues this process. METHODS: We recruited coronary artery disease (CAD) patients with obesity and overweight to analyze the association between MCP-1 and HDL2-C by Pearson correlation coefficients. We performed [3H]-cholesterol efflux assay to demonstrate the effect of MCP-1 and insulin on cholesterol efflux from 3T3-L1 adipocytes to large HDL2 particles. Western blot, RT-qPCR, cell-surface protein assay, and confocal microscopy were performed to determine the regulatory mechanism. RESULTS: Plasma MCP-1 concentrations were negatively correlated with HDL2-C in CAD patients with obesity and overweight (r = -0.60, p < 0.001). In differentiated 3T3-L1 adipocytes, MCP-1 reduced cholesterol efflux to large HDL2 particles by 55.4% via decreasing ATP-binding cassette A1 (ABCA1), ABCG1, and scavenger receptor class B type I (SR-BI) expression. Intriguingly, insulin rescued MCP-1 mediated-inhibition of cholesterol efflux to HDL2 in an Akt phosphorylation-dependent manner. The rescue efficacy of insulin was 138.2% for HDL2. Moreover, insulin increased mRNA and protein expression of ABCA1, ABCG1, and SR-BI at both transcriptional and translational levels via the PI3K/Akt activation. CONCLUSIONS: These findings indicate that MCP-1 impairs cholesterol efflux to large HDL2 particles in adipocytes, which is reversed by insulin via the upregulation of ABCA1, ABCG1, and SR-BI. Therefore, insulin might improve cholesterol imbalance by an anti-inflammatory effect in adipocytes. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR2000033297; Date of registration: 2020/05/ 27; Retrospectively registered.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transportador 1 de Casete de Unión a ATP/genética , Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Adipocitos/metabolismo , Quimiocina CCL2/metabolismo , Colesterol/metabolismo , HDL-Colesterol , Humanos , Insulina , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Sobrepeso/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Depuradores de Clase B/genética , Receptores Depuradores de Clase B/metabolismo
6.
Front Immunol ; 13: 1058606, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36703970

RESUMEN

Introduction: Sepsis is a life-threatening complication resulting from a dysregulated host response to a serious infection, of which bacteria are the most common cause. A rapid differentiation of the gram negative (G-)/gram positive (G+) pathogens facilitates antibiotic treatment, which in turn improves patients' survival. Methods: We performed a prospective, observational study of adult patients in intensive care unit (ICU) unit and underwent the analysis of peripheral blood lymphocyte subsets, cytokines and other clinical indexes. The enrolled 94 patients were divided into no infection group (n=28) and bacterial sepsis group (n=66), and the latter group was subdivided into G- (n=46) and G+ (n=20) sepsis subgroups. Results: The best immune biomarker which differentiated the diagnosis of G- sepsis from G+ sepsis, included activation markers of CD69, human leukocyte antigen DR (HLA-DR) on CD3+CD8+T subset. The ratio of CD3+CD4+CD69+T/CD3+CD8+CD69+T (odds ratio (OR): 0.078(0.012,0.506), P = 0.008), PCT>0.53 ng/ml (OR: 9.31(1.36,63.58), P = 0.023), and CO2CP<26.5 mmol/l (OR: 10.99(1.29, 93.36), P = 0.028) were predictive of G- sepsis (versus G+ sepsis), and the area under the curve (AUC) was 0.947. Additionally, the ratio of CD3+CD4+CD69+T/CD3+CD8+CD69+T ≤ 0.2697 was an independent risk factor for poor ICU discharge in G- sepsis patients (HR: 0.34 (0.13, 0.88), P=0.026). Conclusion: We conclude that enhanced activation of T cells may regulate the excessive inflammatory response of G- bacterial sepsis, and that T cell activation profiles can rapidly distinguish G- sepsis from G+ sepsis and are associated with ICU discharge.


Asunto(s)
Bacteriemia , Infecciones por Bacterias Gramnegativas , Infecciones por Bacterias Grampositivas , Sepsis , Adulto , Humanos , Estudios Prospectivos , Alta del Paciente , Bacterias , Unidades de Cuidados Intensivos
7.
Front Cardiovasc Med ; 8: 700233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34422927

RESUMEN

Background: Although elevation of HDL-C levels by pharmaceutical drugs have no benefit of cardiovascular endpoint, the effect of high-density lipoprotein/apolipoprotein A1 (HDL/apoA-1) replacement therapy on atherosclerosis is controversial. The current meta-analysis analyzed the effects of HDL/apoA-1 replacement therapies on atherosclerotic lesions both in humans and mice. Methods: The PubMed, Cochrane Library, Web of Science, and EMBASE databases were searched through June 6, 2020. The methodological quality of the human studies was assessed using Review Manager (RevMan, version 5.3.). The methodological quality of the mouse studies was assessed using a stair list. STATA (version 14.0) was used to perform all statistical analyses. Results: Fifteen randomized controlled human trials and 17 animal studies were included. The pooled results showed that HDL/apoA-1 replacement therapy use did not significantly decrease the percent atheroma volume (p = 0.766) or total atheroma volume (p = 0.510) in acute coronary syndrome (ACS) patients (N = 754). However, HDL/apoA-1 replacement therapies were significantly associated with the final percent lesion area, final lesion area, and changes in lesion area (SMD, -1.75; 95% CI: -2.21~-1.29, p = 0.000; SMD, -0.78; 95% CI: -1.18~-0.38, p = 0.000; SMD: -2.06; 95% CI, -3.92~-0.2, p = 0.03, respectively) in mice. Conclusions: HDL/apoA-1 replacement therapies are safe but do not significantly improve arterial atheroma volume in humans. The results in animals suggest that HDL/apoA-1 replacement therapies decrease the lesion area. Additional studies are needed to investigate and explain the differences in HDL/apoA-1 replacement therapy efficacies between humans and animals. Trial registration number: Human pooled analysis: PROSPERO, CRD42020210772. prospectively registered.

8.
Ann Palliat Med ; 10(6): 6410-6418, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34237962

RESUMEN

BACKGROUND: Sepsis is common in intensive care units and has a high mortality rate; yet, its pathogenesis and treatment remain unclear. Recent studies have shown that long non-coding RNA plasmacytoma variant translocation 1 (lncRNA-PVT1) plays a pro-inflammatory role in immune-related inflammatory diseases. Therefore, we investigated whether lncRNA-PVT1 plays an important pro-inflammatory effect in the inflammatory response of sepsis. METHODS: Quantitative real-time PCR (RT-qPCR) was employed for the detection of lncRNA-PVT1, interleukin 1ß (IL-1ß), and tumor necrosis factor α (TNF-α) mRNA, and the correlations between their expressions were analyzed. After lncRNA-PVT1 knockdown by lncRNA Smart Silencer, abnormal expressions of lncRNA-PVT1, and IL-1ß and TNF-α mRNA were detected. The expressions of total and phosphorylated protein of p38 were detected by western blotting. The effect of silencing lncRNA-PVT1 on p38 mitogen-activated protein kinase (MAPK) signaling pathway during lipopolysaccharide (LPS)-induced inflammation was subsequently analyzed. The MAPK selective inhibitor, SB202190, was used to block this signaling pathway, and the expressions of lncRNA-PVT1 and TNF-α were detected by RT-qPCR. Furthermore, the effect of partial blockade of the p38 MAPK signaling pathway by SB202190 on the levels of lncRNA-PVT1 was explored. RESULTS: Following treatment of THP-1-derived macrophages with different concentrations of LPS, the levels of lncRNA-PVT1 and IL-1ß, TNF-α mRNA were increased in a dose-dependent manner. Silencing of lncRNA-PVT1 reduced the expressions of IL-1ß and TNF-α mRNA via inhibition of the p38 MAPK signaling pathway. Specifically, inhibiting the p38 MAPK pathway significantly decreased the LPS-induced lncRNA-PVT1 elevation. CONCLUSIONS: Our observations suggest that lncRNA-PVT1 can be silenced to ameliorate LPS-induced inflammation in macrophages via inhibition of the p38 MAPK pathway. Further, the p38 MAPK pathway can regulate the expression of lncRNA-PVT1 via a positive feedback loop.


Asunto(s)
Lipopolisacáridos , ARN Largo no Codificante , Humanos , Inflamación/genética , Sistema de Señalización de MAP Quinasas , Macrófagos/metabolismo , ARN Largo no Codificante/genética , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
9.
J Thorac Dis ; 12(12): 7374-7386, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33447427

RESUMEN

BACKGROUND: Type A acute aortic dissection (TA-AAD) has high mortality, with 50% of patients dying before hospital admission. Hypertension is the most common comorbidity for acute aortic dissection, and effective antihypertensive therapy is still unable to predict the risk of aortic rupture at the medium- and long-term stages. While the presence of renal cyst has been found to increases the risk of thoracic aortic disease, the correlation between renal cyst and TA-AAD with hypertension remains poorly understood. Thus, this study aimed to determine the relationship of renal cyst and TA-AAD with hypertension. METHODS: A retrospective analysis was performed in 464 hypertension patients from August 2014 to August 2019. A total of 230 TA-AAD patients were enrolled in the AD with hypertension group (age 53.79±11.31 years, male 90.87%), and matched by age, sex, and hypertension control to 234 patients without TA-AAD who were enrolled in the non-AD with hypertension group. Patients were divided into three subgroups according to the numbers of renal cysts: no renal cyst, single renal cyst, and multiple renal cysts. RESULTS: In this study, the AD with hypertension group had significantly more single renal cyst and multiple renal cyst cases than did the non-AD with hypertension group. The mean age of the multiple renal cyst subgroup was significantly older than that of the single renal cyst subgroup (57.25±13.00 vs. 51.57±10.75 years) in the AD with hypertension group. There was significantly different distribution of dissection starting points and dissection ending points across three renal cyst subgroups. Multivariate logistic regression analysis indicated that having no renal cyst significantly decreased the risk of TA-AAD in middle-aged and elderly patents, but showed no correlations with those of younger ages. Single renal cyst status also significantly decreased the risk of TA-AAD in elderly patients [odds ratio (OR) =0.129, 95% confidence interval (CI): 0.029-0.575, P=0.007]. CONCLUSIONS: Renal cyst status correlates with the risk of TA-AAD with hypertension in middle-aged and elderly patients, and exhibits different degrees of vascular lesion in aortic dissection. We therefore suggest that different antihypertensive standards should be adopted in different renal cyst status to more effectively prevent aortic dissection.

10.
Asian Nurs Res (Korean Soc Nurs Sci) ; 12(4): 299-303, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30472388

RESUMEN

PURPOSE: Developing a risk prediction model for invasive fungal disease based on an analysis of the disease-related risk factors in critically ill patients in the intensive care unit (ICU) to diagnose the invasive fungal disease in the early stages and determine the time of initiating early antifungal treatment. METHODS: Data were collected retrospectively from 141 critically ill adult patients with at least 4 days of general ICU stay at Sun Yat-sen Memorial Hospital, Sun Yat-sen University during the period from February 2015 to February 2016. Logistic regression was used to develop the risk prediction model. Discriminative power was evaluated by the area under the receiver operating characteristics (ROC) curve (AUC). RESULTS: Sequential organ failure assessment (SOFA) score, antibiotic treatment period, and positive culture of Candida albicans other than normally sterile sites are the three predictors of invasive fungal disease in critically ill patients in the ICU. The model performs well with an ROC-AUC of .73. CONCLUSION: The risk prediction model performs well to discriminate between critically ill patients with or without invasive fungal disease. Physicians could use this prediction model for early diagnosis of invasive fungal disease and determination of the time to start early antifungal treatment of critically ill patients in the ICU.


Asunto(s)
Antifúngicos/uso terapéutico , Cuidados Críticos/métodos , Enfermedad Crítica/terapia , Unidades de Cuidados Intensivos/estadística & datos numéricos , Micosis/diagnóstico , Micosis/tratamiento farmacológico , Medición de Riesgo/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Predicción , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
11.
J Biol Chem ; 291(37): 19532-44, 2016 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-27458015

RESUMEN

High density lipoprotein (HDL) has been proposed to be internalized and to promote reverse cholesterol transport in endothelial cells (ECs). However, the mechanism underlying these processes has not been studied. In this study, we aim to characterize HDL internalization and cholesterol efflux in ECs and regulatory mechanisms. We found mature HDL particles were reduced in patients with coronary artery disease (CAD), which was associated with an increase in CC-chemokine ligand 2 (CCL2). In cultured primary human coronary artery endothelial cells and human umbilical vein endothelial cells, we determined that CCL2 suppressed the binding (4 °C) and association (37 °C) of HDL to/with ECs and HDL cellular internalization. Furthermore, CCL2 inhibited [(3)H]cholesterol efflux to HDL/apoA1 in ECs. We further found that CCL2 induced CC-chemokine receptor 2 (CCR2) expression and siRNA-CCR2 reversed CCL2 suppression on HDL binding, association, internalization, and on cholesterol efflux in ECs. Moreover, CCL2 induced p42/44 mitogen-activated protein kinase (MAPK) phosphorylation via CCR2, and p42/44 MAPK inhibition reversed the suppression of CCL2 on HDL metabolism in ECs. Our study suggests that CCL2 was elevated in CAD patients. CCL2 suppressed HDL internalization and cholesterol efflux via CCR2 induction and p42/44 MAPK activation in ECs. CCL2 induction may contribute to impair HDL function and form atherosclerosis in CAD.


Asunto(s)
Quimiocina CCL2/metabolismo , Colesterol/metabolismo , Enfermedad de la Arteria Coronaria/metabolismo , Regulación de la Expresión Génica , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Lipoproteínas HDL/metabolismo , Sistema de Señalización de MAP Quinasas , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Receptores CCR2/metabolismo , Apolipoproteína A-I/metabolismo , Enfermedad de la Arteria Coronaria/patología , Activación Enzimática , Femenino , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Masculino
12.
Curr Pharm Biotechnol ; 14(6): 623-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24016265

RESUMEN

The ATP-binding cassette A1 (ABCA1) transporter plays a major role in the efflux of lipids by mediating the cellular transport of phospholipids and cholesterol to lipid-poor/lipid-free apolipoprotein A-I (apoA-I) particles and thereby exerting important anti-atherogenic effects. Although the mechanism whereby ABCA1 mediates cholesterol efflux is not completely understood, numerous studies have shown that, in addition to apoA-I, the expression level of the total or cell surface ABCA1 protein is a determining factor for the activity of ABCA1-mediated cholesterol efflux, and defects in ABCA1-mediated cholesterol efflux lead to various pathological conditions in different cells, including cardiovascular and metabolic disorders. It has been widely demonstrated that a growing list of natural and synthetic substances and metabolic regulators that modulate the expression of ABCA1 not only act directly on the ABCA1 gene promoter, but also occurs at the post-transcriptional level via micro-RNAs and post-translationally through the stabilization or localization of the protein. The complex regulatory network of ABCA1 results in promoting or suppressing cholesterol efflux from cells, therefore we speculate that the ABCA1 transporter is emerging as a novel therapeutic target for cardiovascular and metabolic disorders. Thus, ABCA1 is a key modulator of cellular cholesterol efflux and contributes to functional disorders in different types of cells.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/metabolismo , Colesterol/metabolismo , Transportador 1 de Casete de Unión a ATP/genética , Animales , Humanos , Procesamiento Proteico-Postraduccional , Transcripción Genética
13.
J Lipid Res ; 54(5): 1231-40, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23402987

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1) plays crucial roles at multiple stages of atherosclerosis. We hypothesized that MCP-1 might impair the reverse cholesterol transport (RCT) capacity of HepG2 cells by decreasing the cell-surface protein expression of ATP binding cassette A1 (ABCA1), ATP binding cassette G1 (ABCG1), and scavenger receptor class B type I (SR-BI). MCP-1 reduced the total protein and mRNA levels of ABCA1 and SR-BI, but not of ABCG1. MCP-1 decreased the cell-surface protein expression of ABCA1, ABCG1, and SR-BI in dose-dependent and time-dependent manners, as measured using cell-surface biotinylation. We further studied the phosphoinositide 3-kinase (PI3K)/serine/threonine protein kinase Akt pathway in regulating receptor trafficking. Both the translation and transcription of ABCA1, ABCG1, and SR-BI were not found to be regulated by the PI3K/Akt pathway. However, the cell-surface protein expression of ABCA1, ABCG1, and SR-BI could be regulated by PI3K activity, and PI3K activation corrected the MCP-1-induced decreases in the cell-surface protein expression of ABCA1, ABCG1, and SR-BI. Moreover, we found that MCP-1 decreased the lipid uptake by HepG2 cells and the ABCA1-mediated cholesterol efflux to apoA-I, which could be reversed by PI3K activation. Our data suggest that MCP-1 impairs RCT activity in HepG2 cells by a PI3K/Akt-mediated posttranslational regulation of ABCA1, ABCG1, and SR-BI cell-surface expression.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Aterosclerosis/genética , Quimiocina CCL2/genética , Receptores Depuradores de Clase B/genética , Transportador 1 de Casete de Unión a ATP , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1 , Transportadoras de Casetes de Unión a ATP/metabolismo , Aterosclerosis/patología , Quimiocina CCL2/metabolismo , Colesterol/metabolismo , Elafina/metabolismo , Regulación de la Expresión Génica , Células Hep G2 , Humanos , Proteína Oncogénica v-akt/metabolismo , Procesamiento Proteico-Postraduccional , Receptores Depuradores de Clase B/metabolismo , Transducción de Señal
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