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1.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2820-2826, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31359696

RESUMO

The aim of this study was to explore the effect of emodin on lipid accumulation and inflammation in hepatocytes. The cell morphology was observed by microscopy. LDH release was detected by the kit. Levels of intracellular lipid droplets were observed by oil red O staining. The contents of TC and TG in cells were detected by the kit. Western blot was used to determine protein expressions of FASN,SREBF2,APOB,IL-6 and p-NF-κB in hepatocytes. The results showed that the levels of L02 cell LDH were significantly increased after being treated with emodin,and the cells showed shrinkage,volume reduction,decrease in quantity with the increase of dose. Red lipid droplets were observed in L02 hepatocytes. Intracellular TC and TG contents of L02 cell increased in a concentrationdependent manner,with significant differences between medium and high-dose groups( P < 0. 05). Protein expressions of FASN,SREBF2,IL-6 and p-NF-κB were significantly higher than those of the control group,and the expression level of APOB was significantly lower than that of the control group( P<0. 05). In conclusion,emodin could induce lipid accumulation and inflammatory damage in hepatocytes in a dose-dependent manner,which in turn could damage liver cells. This process was related to the up-regulation of FASN,SREBF2,IL-6,p-NF-κB,as well as the down-regulation of the protein expression of APOB.


Assuntos
Emodina/farmacologia , Hepatócitos/efeitos dos fármacos , Metabolismo dos Lipídeos , Apolipoproteína B-100/metabolismo , Células Cultivadas , Ácido Graxo Sintase Tipo I/metabolismo , Hepatócitos/metabolismo , Humanos , Inflamação , Interleucina-6/metabolismo , Lipídeos , NF-kappa B/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
2.
Clin Chim Acta ; 495: 382-393, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078566

RESUMO

A new concept to account for the process of postprandial remnant lipoprotein metabolism is proposed based on the characteristics of lipoprotein particles and their receptors. The characteristics of remnant lipoprotein (RLP) were investigated using an immuno-separation method. The majority of the postprandial lipoproteins increased after fat intake was shown to be VLDL remnants, not chylomicron (CM) remnants, based on the significantly high ratio of apoB100/apoB48 in the RLP and the high degree of similarity in the particle size of the apoB48 and apoB100 carrying lipoproteins, which fluctuate in parallel during a 6 h period after fat intake. The VLDL receptor was discovered as a receptor for TG-rich lipoprotein metabolism and is located in peripheral tissues such as skeletal muscle, adipose tissue, etc., but not in the liver. Postprandial VLDL particles are strongly bound and internalized into cells expressing the VLDL receptor. Ligands that bind to VLDL receptor, such as LPL and Lp(a), present in RLP. The presence of various specific ligands in VLDL remnants may enhance the capacity for binding to the VLDL receptor, which play the role primarily for energy delivery to the peripheral tissues, but is also a causal factor in atherogenic diseases when excessively and/or continuously remained in plasma.


Assuntos
Lipoproteínas VLDL/metabolismo , Período Pós-Prandial , Receptores de LDL/fisiologia , Apolipoproteína B-100/metabolismo , Aterosclerose/etiologia , Remanescentes de Quilomícrons , Metabolismo Energético , Humanos , Ligantes , Tamanho da Partícula
3.
Metabolism ; 96: 8-11, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30995439

RESUMO

CONTEXT: Lipoprotein(a) [Lp(a)] is a highly atherogenic lipoprotein characterized by apolipoprotein(a) [apo(a)] covalently bounded to apoB-100 (apoB). However, the metabolism of apo(a) and apoB within plasma Lp(a) particles in patients on statins remains unclear. METHODS: The kinetics of Lp(a)-apo(a) and Lp(a)-apoB were determined in 20 patients with elevated Lp(a) (≥0.8 g/L; n = 10) and normal Lp(a) (≤0.3 g/L; n = 10) using stable isotope techniques and compartmental modeling. Plasma apo(a) concentration was measured using liquid chromatography-mass spectrometry. All patients were on statin therapy and were studied in the fasting state. RESULTS: The fractional catabolic rate (FCR) of Lp(a)-apo(a) was not significantly different from that of Lp(a)-apoB in statin-treated patients with elevated or normal Lp(a) (P > 0.05 in both). Lp(a)-apo(a) FCR was significantly correlated with Lp(a)-apoB in patients with elevated and normal Lp(a) concentrations (r = 0.970 and r = 0.979, respectively; all P < 0.001) with Lin's concordance test showing substantial agreement between the FCRs of Lp(a)-apo(a) and Lp(a)-apoB in patients with elevated and normal Lp(a) concentrations (rc = 0.978 and rc = 0.966, respectively). CONCLUSION: Our data indicate that the apo(a) and apoB proteins within Lp(a) particles have similar FCR and are therefore tightly coupled as an Lp(a) holoparticle in statin-treated patients with elevated and normal Lp(a) concentrations.


Assuntos
Apolipoproteína B-100/metabolismo , Apolipoproteínas A/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipoproteína(a)/metabolismo , Adolescente , Adulto , Idoso , Feminino , Humanos , Hiperlipidemias/sangue , Cinética , Lipoproteína(a)/sangue , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Food Funct ; 10(5): 2471-2479, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-30977496

RESUMO

The present study aimed to investigate the effects of n-3 fatty acid supplements on urine metabolite profiling and their correlation with metabolic risk factors in Chinese T2D patients. A double-blind randomized controlled trial was conducted in 59 Chinese patients with T2D, who were randomized to receive fish oil (FO), flaxseed oil (FSO) or corn oil (CO, serving as a control group) capsules for 180 days. Morning urine samples were collected before and after the intervention and were analyzed for metabolomics by UHPLC-Q-Exactive Orbitrap/MS in positive and negative ionization modes. In the FO group, levels of 2-hexenoylcarnitine (C6:1) (p < 0.001) and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF) (p = 0.004) were significantly increased while hydroxyisovaleroyl carnitine (C5:OH) (p < 0.001) was significantly decreased compared with the CO group. In addition, geranylacetone (p = 0.023) and citronellyl propionate (p = 0.038) levels were significantly elevated, while dihydrojasmonic acid (p = 0.003) was significantly reduced in the FSO group compared with that in the CO group. Moreover, increased C6:1 was correlated with decreased serum triglycerides (r = -0.340, p = 0.020). The change of urine CMPF showed inverse correlation with blood urea nitrogen (BUN) (r = -0.338, p = 0.020), while C5:OH was positively correlated with apolipoprotein B (APOB) and BUN (r = 0.386, p = 0.015; r = 0.327, p = 0.025). Besides, the change of urine CMPF was positively correlated with serum CMPF (r = 0.646, p < 0.001). In conclusion, the present study confirmed that CMPF is a strong biomarker of fish oil, and indicated that marine n-3 PUFA intake might have a beneficial effect on lipid metabolism and renal function in patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Ácidos Graxos Ômega-3/administração & dosagem , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Óleo de Milho/administração & dosagem , Óleo de Milho/química , Óleo de Milho/urina , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/urina , Suplementos Nutricionais/análise , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/urina , Óleos de Peixe/administração & dosagem , Óleos de Peixe/química , Óleos de Peixe/urina , Humanos , Óleo de Semente do Linho/administração & dosagem , Óleo de Semente do Linho/química , Urina/química
5.
Pregnancy Hypertens ; 15: 154-160, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30825913

RESUMO

OBJECTIVE: Preeclampsia and intrauterine growth restriction (IUGR) are related conditions. We aimed to characterise common lipid changes. METHODS: Triglyceride and cholesterol levels of patients 24-42 weeks of gestation with IUGR (n = 52), hypertensive IUGR (HIUGR, n = 28), and preeclampsia without IUGR (PE, n = 56) were compared to a control group (CTRL, n = 167). In addition, 60 sera (n = 10 of each pathology IUGR, HIUGR, PE (without IUGR) compared to n = 30 matched CTRL) of severe early onset cases <34 weeks of gestation were chosen and further analysed by ultracentrifugation lipid subfractionation including VLDL, IDL, LDL, and HDL composition. RESULTS: In the full cohort we found low cholesterol in IUGR (p = 0.0405), while triglyceride levels were high in PE (p < 0.0001). Lipid concentrations in HIUGR did not differ significantly from CTRL. In the 60 patients analysed by lipid subfractionation, triglyceride levels were increased in the VLDL subfraction in PE (p < 0.01), however, LDL-bound ApoB and cholesterol levels were lower in IUGR and HIUGR (p < 0.0001 for total cholesterol and p < 0.001 for ApoB in both groups), but not in PE when compared to CTRL. CONCLUSION: Low cholesterol, especially LDL cholesterol levels are a feature of IUGR while high triglyceride levels are a feature of preeclampsia. Increased VLDL-triglycerides suggest a disturbed conversion to LDL in preeclampsia. Of note, the presence of IUGR in hypertensive disorders further alters lipid profiles, which may explain heterogeneous data on lipid values for preeclampsia in the literature. Study groups have to be selected carefully to avoid misinterpretation.


Assuntos
Apolipoproteína B-100/metabolismo , Retardo do Crescimento Fetal/sangue , Lipoproteínas/sangue , Pré-Eclâmpsia/sangue , Adulto , Estudos de Casos e Controles , LDL-Colesterol/sangue , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Gravidez , Triglicerídeos/sangue
6.
Cardiovasc Res ; 115(1): 243-254, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29917052

RESUMO

Aims: Oxidative stress and inflammation play an important role in the progression of atherosclerosis. Transcription factor NF-E2-related factor 2 (Nrf2) has antioxidant and anti-inflammatory effects in the vessel wall, but paradoxically, global loss of Nrf2 in apoE deficient mice alleviates atherosclerosis. In this study, we investigated the effect of global Nrf2 deficiency on early and advanced atherogenesis in alternative models of atherosclerosis, LDL receptor deficient mice (LDLR-/-), and LDLR-/- mice expressing apoB-100 only (LDLR-/- ApoB100/100) having a humanized lipoprotein profile. Methods and results: LDLR-/- mice were fed a high-fat diet (HFD) for 6 or 12 weeks and LDLR-/-ApoB100/100 mice a regular chow diet for 6 or 12 months. Nrf2 deficiency significantly reduced early and more advanced atherosclerosis assessed by lesion size and coverage in the aorta in both models. Nrf2 deficiency in LDLR-/- mice reduced total plasma cholesterol after 6 weeks of HFD and triglycerides in LDLR-/-ApoB100/100 mice on a chow diet. Nrf2 deficiency aggravated aortic plaque maturation in aged LDLR-/-ApoB100/100 mice as it increased plaque calcification. Moreover, ∼36% of Nrf2-/-LDLR-/-ApoB100/100 females developed spontaneous myocardial infarction (MI) or sudden death at 5 to 12 months of age. Interestingly, Nrf2 deficiency increased plaque instability index, enhanced plaque inflammation and calcification, and reduced fibrous cap thickness in brachiocephalic arteries of LDLR-/-ApoB100/100 female mice at age of 12 months. Conclusions: Absence of Nrf2 reduced atherosclerotic lesion size in both atherosclerosis models, likely via systemic effects on lipid metabolism. However, Nrf2 deficiency in aged LDLR-/-ApoB100/100 mice led to an enhanced atherosclerotic plaque instability likely via increased plaque inflammation and oxidative stress, which possibly predisposed to MI and sudden death.


Assuntos
Aorta/metabolismo , Doenças da Aorta/metabolismo , Aterosclerose/metabolismo , Hipercolesterolemia/complicações , Fator 2 Relacionado a NF-E2/deficiência , Placa Aterosclerótica , Fatores Etários , Animais , Aorta/patologia , Doenças da Aorta/etiologia , Doenças da Aorta/patologia , Doenças da Aorta/prevenção & controle , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Aterosclerose/etiologia , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Células Cultivadas , Dieta Hiperlipídica , Modelos Animais de Doenças , Progressão da Doença , Feminino , Hipercolesterolemia/genética , Mediadores da Inflamação/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo , Receptores de LDL/deficiência , Receptores de LDL/genética , Triglicerídeos/sangue
7.
Am J Physiol Endocrinol Metab ; 316(1): E16-E33, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30153063

RESUMO

Polycystic ovary syndrome (PCOS) is highly associated with cardiometabolic risk and the metabolic syndrome (MetS), predisposing women to increased risk of developing type 2 diabetes and cardiovascular disease. Metformin is commonly used to treat insulin resistance-glucose intolerance, and flutamide, an androgen receptor (AR) antagonist, is used to target hyperandrogenemia and dyslipidemia. Currently, the physiological mechanism of action of these treatments on androgen, lipidogenic, and insulin signaling pathways remains unclear in PCOS. The aim of this study was to investigate the effects and mechanisms of action of metformin and flutamide on plasma lipid-apolipoprotein (Apo)B-lipoprotein and insulin-glucose metabolism, and endocrine-reproductive indices in a PCOS-prone MetS rodent model. PCOS-prone rodents were treated with metformin (300 mg/kg body wt), flutamide (30 mg/kg body wt), or metformin + flutamide combination treatment for 6 wk. Metformin was shown to improve fasting insulin and HOMA-IR, whereas flutamide and combination treatment were shown to reduce plasma triglycerides, ApoB48, and ApoB100, and this was associated with decreased intestinal secretion of ApoB48/triglyceride. Flutamide and metformin were shown to reduce plasma androgen indices and to improve ovarian primary and preovulatory follicle frequency. Metformin treatment increased hepatic estrogen receptor (ER)α, and metformin-flutamide decreased intestinal AR and increased ERα mRNA expression. Metformin-flutamide treatment upregulated hepatic and intestinal insulin signaling, including insulin receptor, MAPK1, and AKT2. In conclusion, cardiometabolic risk factors, in particular ApoB-hypertriglyceridemia, are independently modulated via the AR, and understanding the contribution of AR and insulin-signaling pathways further may facilitate the development of targeted interventions in high-risk women with PCOS and MetS.


Assuntos
Antagonistas de Androgênios/farmacologia , Glicemia/efeitos dos fármacos , Receptor alfa de Estrogênio/efeitos dos fármacos , Flutamida/farmacologia , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Síndrome Metabólica/metabolismo , Metformina/farmacologia , Animais , Apolipoproteína B-100/efeitos dos fármacos , Apolipoproteína B-100/metabolismo , Apolipoproteína B-48/efeitos dos fármacos , Apolipoproteína B-48/metabolismo , Apolipoproteínas B/efeitos dos fármacos , Apolipoproteínas B/metabolismo , Glicemia/metabolismo , Doenças Cardiovasculares , Modelos Animais de Doenças , Receptor alfa de Estrogênio/genética , Feminino , Fase Folicular , Resistência à Insulina , Mucosa Intestinal/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Síndrome do Ovário Policístico/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro , Ratos , Receptor de Insulina/efeitos dos fármacos , Receptor de Insulina/metabolismo , Risco , Triglicerídeos/metabolismo
8.
Int J Biol Macromol ; 122: 195-200, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30312697

RESUMO

Advanced glycation end-products (AGEs) can aggregate amid incessant inflammation, as may be available in patients with rheumatoid arthritis. d-Ribose reacts more promptly than glucose monosaccharide to the proteins and forms heterogeneous group of products known as AGEs. Obesity includes persons with provocative joint inflammation with increased lipid profile. Immunogenic evidences recommend a cross-sectional relationship between glycated LDL-Apo B100 and inflammation. The point of this examination was to look at the connection between d-ribose glycated ApoB100 (ApoB100-AGE) with obesity and rheumatoid arthritis. The binding specificity of auto-antibodies against ApoB100-AGE antigen present in obesity and rheumatoid arthritis patient's serum were inspected by direct binding and was further established by competitive inhibition ELISA. In the present study, hydroxyl radical, superoxide radical, ketoamine moieties, hydroxyl-methyl furfural (HMF) and carbonyl substances were evaluated in the patients' serum via respective specific methods. The prevalence of auto-antibodies against ApoB100-AGE antigen was recorded to be 58% and 52.86% from obese and rheumatoid arthritis patient respectively in contrast to its native analogue (P < 0.001). Moreover, the autoantibodies present in obese and arthritis patients were found to be highly specific towards ApoB100-AGE as confirmed by inhibition ELISA.


Assuntos
Apolipoproteína B-100/metabolismo , Artrite Reumatoide/metabolismo , Correlação de Dados , Produtos Finais de Glicação Avançada/metabolismo , Lipoproteínas LDL/metabolismo , Obesidade/metabolismo , Adulto , Idoso , Feminino , Glicosilação , Humanos , Radical Hidroxila/metabolismo , Masculino , Pessoa de Meia-Idade , Superóxidos/metabolismo
9.
J Dairy Sci ; 102(1): 833-845, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30415861

RESUMO

Fatty liver is a common metabolic disorder in dairy cows during the transition period. Perilipin 5 (PLIN5), a lipid droplet coat protein, plays important roles in the development of hepatic steatosis in mice and humans. Whether PLIN5 plays a role in the development of fatty liver in dairy cows is unknown. An in vivo study consisting of 10 healthy and 10 cows with fatty liver was performed to harvest liver tissue and blood samples. In addition, hepatocytes isolated from calves were infected with PLIN5 overexpression adenovirus for 48 h; treated with 0, 0.6, 1.2, or 2.4 mM nonesterified fatty acids (NEFA) for 24 h; or infected with PLIN5 silencing adenovirus for 48 h and then treated with 1.2 mM NEFA for 24 h. Serum concentrations of NEFA and ß-hydroxybutyrate were greater in cows with fatty liver. Milk production and plasma glucose concentrations were lower in cows with fatty liver. The results revealed that PLIN5 is highly expressed in steatotic liver and localized to lipid droplets. The abundance of fatty acid and triacylglycerol (TAG) synthesis-related proteins including sterol regulatory element binding protein-1c, fatty acid synthase, acetyl-coA carboxylase 1, diacylglycerol acyltransferase 1, and diacylglycerol acyltransferase 2 was greater in the liver of cows with fatty liver. In contrast, the abundance of microsomal triglyceride transfer protein (MTP), apolipoprotein B100, and apolipoprotein E was lower in the liver of cows with fatty liver. Consequently, cows with fatty liver exhibited severe hepatic TAG accumulation and lower blood concentration of very low density lipoprotein apolipoprotein B (VLDL-ApoB). Overexpression of PLIN5 and exogenous NEFA in cultured hepatocytes increased the abundance of sterol regulatory element binding protein-1, fatty acid synthase, acetyl-coA carboxylase 1, diacylglycerol acyltransferase 1, and diacylglycerol acyltransferase 2 but decreased the abundance of microsomal triglyceride transfer protein, apolipoprotein B100, and apolipoprotein E, which promoted TAG synthesis and inhibited VLDL-ApoB assembly, inducing lipid accumulation. Importantly, knockdown of PLIN5 attenuated the upregulation of TAG synthesis and downregulation of VLDL-ApoB assembly induced by NEFA. Overall, these data suggest that NEFA activate PLIN5, leading to TAG accumulation and inhibition of VLDL assembly. As such, these mechanisms explain in part the development of hepatic steatosis in dairy cows.


Assuntos
Doenças dos Bovinos/metabolismo , Fígado Gorduroso/veterinária , Lipídeos/biossíntese , Lipoproteínas VLDL/metabolismo , Perilipina-5/metabolismo , Ácido 3-Hidroxibutírico/sangue , Animais , Apolipoproteína B-100/metabolismo , Apolipoproteínas E/metabolismo , Proteínas de Transporte/metabolismo , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácidos Graxos/metabolismo , Ácidos Graxos não Esterificados/sangue , Fígado Gorduroso/sangue , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Feminino , Gotículas Lipídicas/metabolismo , Fígado/metabolismo , Camundongos , Perilipina-5/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/metabolismo
10.
Arterioscler Thromb Vasc Biol ; 39(1): 63-72, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30580564

RESUMO

Objective- Apo (apolipoprotein) CIII inhibits lipoprotein lipase (LpL)-mediated lipolysis of VLDL (very-low-density lipoprotein) triglyceride (TG) and decreases hepatic uptake of VLDL remnants. The discovery that 5% of Lancaster Old Order Amish are heterozygous for the APOC3 R19X null mutation provided the opportunity to determine the effects of a naturally occurring reduction in apo CIII levels on the metabolism of atherogenic containing lipoproteins. Approach and Results- We conducted stable isotope studies of VLDL-TG and apoB100 in 5 individuals heterozygous for the null mutation APOC3 R19X (CT) and their unaffected (CC) siblings. Fractional clearance rates and production rates of VLDL-TG and apoB100 in VLDL, IDL (intermediate-density lipoprotein), LDL, apo CIII, and apo CII were determined. Affected (CT) individuals had 49% reduction in plasma apo CIII levels compared with CCs ( P<0.01) and reduced plasma levels of TG (35%, P<0.02), VLDL-TG (45%, P<0.02), and VLDL-apoB100 (36%, P<0.05). These changes were because of higher fractional clearance rates of VLDL-TG and VLDL-apoB100 with no differences in production rates. CTs had higher rates of the conversion of VLDL remnants to LDL compared with CCs. In contrast, rates of direct removal of VLDL remnants did not differ between the groups. As a result, the flux of apoB100 from VLDL to LDL was not reduced, and the plasma levels of LDL-cholesterol and LDL-apoB100 were not lower in the CT group. Apo CIII production rate was lower in CTs compared with CCs, whereas apo CII production rate was not different between the 2 groups. The fractional clearance rates of both apo CIII and apo CII were higher in CTs than CCs. Conclusions- These studies demonstrate that 50% reductions in plasma apo CIII, in otherwise healthy subjects, results in a significantly higher rate of conversion of VLDL to LDL, with little effect on direct hepatic uptake of VLDL. When put in the context of studies demonstrating significant protection from cardiovascular events in individuals with loss of function variants in the APOC3 gene, our results provide strong evidence that therapies which increase the efficiency of conversion of VLDL to LDL, thereby reducing remnant concentrations, should reduce the risk of cardiovascular disease.


Assuntos
Apolipoproteína C-III/fisiologia , Lipídeos/sangue , Lipoproteínas/metabolismo , Adulto , Idoso , Apolipoproteína B-100/metabolismo , Apolipoproteína C-III/deficiência , Apolipoproteína C-III/genética , Feminino , Humanos , Lipólise , Lipoproteínas IDL/metabolismo , Lipoproteínas VLDL/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação
11.
J Lipid Res ; 60(2): 436-445, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30563909

RESUMO

Atherosclerosis is associated with increased lipid peroxidation, leading to generation of multiple oxidation-specific epitopes (OSEs), contributing to the pathogenesis of atherosclerosis and its clinical manifestation. Oxidized cholesteryl esters (OxCEs) are a major class of OSEs found in human plasma and atherosclerotic tissue. To evaluate OxCEs as a candidate biomarker, we generated a novel mouse monoclonal Ab (mAb) specific to an OxCE modification of proteins. The mAb AG23 (IgG1) was raised in C57BL6 mice immunized with OxCE-modified keyhole limpet hemocyanin, and hybridomas were screened against OxCE-modified BSA. This method ensures mAb specificity to the OxCE modification, independent of a carrier protein. AG23 specifically stained human carotid artery atherosclerotic lesions. An ELISA method, with AG23 as a capture and either anti-apoAI or anti-apoB-100 as the detection Abs, was developed to assay apoAI and apoB-100 lipoproteins that have one or more OxCE epitopes. OxCE-apoA or OxCE-apoB did not correlate with the well-established oxidized phospholipid-apoB biomarker. In a cohort of subjects treated with atorvastatin, OxCE-apoA was significantly lower than in the placebo group, independent of the apoAI levels. These results suggest the potential diagnostic utility of a new biomarker assay to measure OxCE-modified lipoproteins in patients with CVD.


Assuntos
Anticorpos Monoclonais/imunologia , Apolipoproteína A-I/metabolismo , Apolipoproteína B-100/metabolismo , Ésteres do Colesterol/sangue , Ésteres do Colesterol/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Animais , Ésteres do Colesterol/imunologia , Humanos , Camundongos , Oxirredução
12.
Atherosclerosis ; 277: 448-456, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30270084

RESUMO

BACKGROUND AMD AIMS: APOB mutations are a rare cause of familial hypercholesterolaemia (FH) and, until recently, routine genetic diagnosis only included the study of two small APOB fragments. In previous years, 5 novel functional mutations have been described in APOB fragments not routinely studied, our group having functionally characterized 2 of them. The main aim of this work was to identify and characterize novel alterations in APOB to assess the genetic cause of hypercholesterolemia in patients with a clinical diagnosis of FH. METHODS: We performed next generation sequencing of 48 Portuguese clinical FH patients, who were apparently mutation negative. All variants found in APOB were annotated. For functional studies, LDL from index patients and relatives was separated and marked with FITC-LDL for flow cytometry assays in lymphocytes and U937 growth assays. RESULTS: A total of 11 potential pathogenic variants were identified. Variants p.(Pro994Leu) and p.(Thr3826Met) in exons 19 and 26 were found in 4 patients, and in vitro analysis was performed for these variants. An exon 26 alteration (p.(Thr3826Met)) showed a decrease in binding and internalization of LDL, and in U937 growth assays that was similar to the effect with p.(Arg3527Gln). An alteration in exon 19 had a neutral effect. CONCLUSIONS: The spectrum of functional alterations in APOB outside the fragments routinely screened is slowly growing. Screening of all 29 exons of APOB is advised for FH routine diagnosis, but functional characterization is necessary for pathogenicity assessment. It is expected that the number of patients with functional APOB mutations will increase in the near future.


Assuntos
Apolipoproteína B-100/genética , LDL-Colesterol/sangue , Hiperlipoproteinemia Tipo II/genética , Mutação , Adolescente , Adulto , Apolipoproteína B-100/metabolismo , Biomarcadores/sangue , Estudos de Casos e Controles , Proliferação de Células , Criança , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/diagnóstico , Masculino , Pessoa de Meia-Idade , Fenótipo , Portugal , Linfócitos T/metabolismo , Células U937
13.
Kardiologiia ; 58(6): 70-78, 2018 06.
Artigo em Russo | MEDLINE | ID: mdl-30362439

RESUMO

Lipoprotein(a) [Lp(a)] consists of an LDL-like particle in which the apolipoprotein B100 is covalently bound to apolipoprotein(a) by a single disulfide bond. Lp(a) is synthesized in the liver and its plasma concentration varies from 0 to 400 mg/dl. Increased level of Lp(a) is considered to be an independent risk factor of cardiovascular diseases and coronary heart disease. Data about the significance of hyperlipoproteinemia(a) in the development of atherosclerosis of peripheral (lower limbs) and carotid arteries remain controversial. This review is devoted to Lp(a), its relationship with atherosclerosis of different vascular beds, as well as modern possibilities of hyperlipoproteinemia(a) correction.


Assuntos
Aterosclerose/etiologia , Doenças das Artérias Carótidas/etiologia , Lipoproteína(a)/metabolismo , Apolipoproteína B-100/metabolismo , Aterosclerose/metabolismo , Doenças Cardiovasculares , Doenças das Artérias Carótidas/metabolismo , Humanos , Fatores de Risco
14.
J Lipid Res ; 59(10): 1940-1950, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30115754

RESUMO

Intracellular lipid droplets (LDs) supply fatty acids for energy, membrane biogenesis, and lipoprotein secretion. The surface monolayer of LDs is composed of phospholipids, primarily phosphatidylcholine (PC), that stabilize the neutral lipid core of triglyceride (TG). To determine the relationship between PC synthesis and TG storage and secretion in chylomicrons, we used a model of intestinal-derived human epithelial colorectal adenocarcinoma (Caco2) cells with knockout of PCYT1A, which encodes the rate-limiting enzyme CTP:phosphocholine cytidylyltransferase (CCT)α in the CDP-choline pathway, that were treated with the fatty acid oleate. CRISPR/Cas9 knockout of CCTα in Caco2 cells (Caco2-KO cells) reduced PC synthesis by 50%. Compared with Caco2 cells, Caco2-KO cells exposed to oleate had fewer and larger LDs and greater TG accumulation as a result. The addition of exogenous lysophosphatidylcholine to Caco2-KO cells reversed the LD morphology defect. Caco2-KO cells, differentiated into epithelial monolayers, accumulated intracellular TG and had deficient TG and chylomicron-associated apoB48 secretion; apoB100 secretion was unaffected by CCTα knockout or oleate. Metabolic-labeling and LD imaging of Caco2-KO cells indicated preferential shuttling of de novo synthesized TG into larger LDs rather than into chylomicrons. Thus, reduced de novo PC synthesis in Caco2 cells enhances TG storage in large LDs and inhibits apoB48 chylomicron secretion.


Assuntos
Quilomícrons/metabolismo , Fosfatidilcolinas/biossíntese , Triglicerídeos/metabolismo , Apolipoproteína B-100/metabolismo , Células CACO-2 , Colina-Fosfato Citidililtransferase/deficiência , Colina-Fosfato Citidililtransferase/genética , Técnicas de Inativação de Genes , Humanos , Gotículas Lipídicas/metabolismo
15.
Arterioscler Thromb Vasc Biol ; 38(8): 1890-1900, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29976766

RESUMO

Objective- SAA (serum amyloid A) is a family of acute-phase reactants that have proinflammatory and proatherogenic activities. SAA is more lipophilic than apoA-I (apolipoprotein A-I), and during an acute-phase response, <10% of plasma SAA is found lipid-free. In most reports, SAA is found exclusively associated with high-density lipoprotein; however, we and others have reported SAA on apoB (apolipoprotein B)-containing lipoproteins in both mice and humans. The goal of this study was to determine whether SAA is an exchangeable apolipoprotein. Approach and Results- Delipidated human SAA was incubated with SAA-free human lipoproteins; then, samples were reisolated by fast protein liquid chromatography, and SAA analyzed by ELISA and immunoblot. Both in vitro and in vivo, we show that SAA associates with any lipoprotein and does not remain in a lipid-free form. Although SAA is preferentially found on high-density lipoprotein, it can exchange between lipoproteins. In the presence of CETP (cholesterol ester transfer protein), there is greater exchange of SAA between lipoproteins. Subjects with diabetes mellitus, but not those with metabolic syndrome, showed altered SAA lipoprotein distribution postprandially. Proteoglycan-mediated lipoprotein retention is thought to be an underlying mechanism for atherosclerosis development. SAA has a proteoglycan-binding domain. Lipoproteins containing SAA had increased proteoglycan binding compared with SAA-free lipoproteins. Conclusions- Thus, SAA is an exchangeable apolipoprotein and increases apoB-containing lipoproteins' proteoglycan binding. We and others have previously reported the presence of SAA on low-density lipoprotein in individuals with obesity, diabetes mellitus, and metabolic syndrome. We propose that the presence of SAA on apoB-containing lipoproteins may contribute to cardiovascular disease development in these populations.


Assuntos
Apolipoproteínas/metabolismo , Proteína Amiloide A Sérica/metabolismo , Idoso , Animais , Apolipoproteína B-100/metabolismo , Apolipoproteínas/sangue , Proteínas de Transferência de Ésteres de Colesterol/genética , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Diabetes Mellitus/sangue , Feminino , Humanos , Lipoproteínas HDL/metabolismo , Masculino , Síndrome Metabólica/sangue , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Obesidade/sangue , Período Pós-Prandial , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteoglicanas/metabolismo , Proteína Amiloide A Sérica/deficiência , Proteína Amiloide A Sérica/genética
16.
Physiol Rep ; 6(14): e13789, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30009570

RESUMO

Curcumin, a naturally occurring plant polyphenolic compound, may have beneficial effects in nonalcoholic steatohepatitis (NASH) development. We examined whether curcumin supplementation could be used in both prevention and treatment of NASH with fibrosis. Female Wistar rats were provided ad libitum access to a "western diet" (WD) high in fat (43% kcal), sucrose (29% kcal), and cholesterol (2% w/v), as well as 15% fructose drinking water. Intraperitoneal CC14 injections (0.5 mL/kg) were also administered at weeks 1, 2, 4, and 6 to accelerate development of a NASH with fibrosis phenotype. Rats were randomized to four groups (n = 9-12/group) and fed ad libitum: (1) WD for 8-weeks (8WD), (2) WD enriched with curcumin for 8-weeks (8WD+C; 0.2% curcumin, BCM-95, DolCas Biotech) to assess prevention, (3) WD for 12-weeks (12WD), (4) WD for 8-weeks followed by 4-weeks WD+C (12WD+C) to assess treatment. Curcumin prevention (8WD vs. 8WD+C) attenuated (P < 0.05) histological liver inflammation, molecular markers of fibrosis (Col1a1 mRNA) and a serum marker of liver injury (AST). Curcumin treatment (12WD vs. 12WD+C) reduced (P < 0.05) hepatocellular inflammation, steatosis, NAFLD Activity Scores, and serum markers of liver injury (AST, ALP). Moreover, curcumin treatment also increased hepatic pACC/ACC, ApoB100, and SOD1 protein, and decreased hepatic FGF-21 levels; whereas, curcumin prevention increased hepatic glutathione levels. Both curcumin prevention and treatment reduced molecular markers of hepatic fibrosis (Col1a1 mRNA) and inflammation (TNF-α, SPP1 mRNA). Curcumin supplementation beneficially altered the NASH phenotype in female Wistar rats, particularly the reversal of hepatocellular inflammation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Curcumina/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Apolipoproteína B-100/metabolismo , Colágeno/metabolismo , Curcumina/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Feminino , Glutationa/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Osteopontina/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
17.
Can J Physiol Pharmacol ; 96(7): 668-675, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29756473

RESUMO

Secretion of very low density lipoprotein (VLDL) by the liver is an important physiological process; however, the rate of VLDL secretion is determined by its transport from the endoplasmic reticulum (ER) to the Golgi. This transport event is facilitated by a specialized ER-derived vesicle, the VLDL transport vesicle (VTV). We have reported earlier a detailed VTV proteome, which revealed that reticulon 3 (RTN3) is uniquely present in the VTV. Our immunoblotting and electron microscopic data demonstrate that RTN3 is enriched in the VTV; however, other ER-derived vesicles do not contain RTN3. Co-immunoprecipitation data coupled with confocal microscopic analyses strongly suggest that RTN3 interacts with VLDL core protein, apoB100, at the ER level. Our data show that either blocking of RTN3 using specific antibodies or RTN3 knockdown resulted in significant reduction in VTV biogenesis from hepatic ER membranes. Additionally, VLDL secretion from hepatocytes was significantly decreased when RTN3 was silenced by RTN3 siRNA. We conclude that RTN3 regulates VLDL secretion by controlling VTV-mediated ER-to-Golgi transport of nascent VLDL.


Assuntos
Apolipoproteína B-100/metabolismo , Proteínas de Transporte/metabolismo , Lipoproteínas VLDL/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Vesículas Transportadoras/metabolismo , Animais , Proteínas de Transporte/genética , Retículo Endoplasmático/metabolismo , Técnicas de Silenciamento de Genes , Complexo de Golgi/metabolismo , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Fígado/citologia , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Cultura Primária de Células , Ligação Proteica , Transporte Proteico , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Lipids ; 53(3): 345-351, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29701265

RESUMO

Recently we have found cyclopropaneoctanoic acid 2-hexyl (CPOA2H) in humans and demonstrated its elevated levels in patients with metabolic diseases associated with hypertriglyceridemia. However, it is still unclear whether CPOA2H may influence lipid metabolism in lipogenic tissues. To verify this, HepG2 hepatocytes and 3T3-L1 adipocytes were cultured with various concentrations of CPOA2H, and then the expressions of genes associated with lipid metabolism were determined. Incubation with CPOA2H at concentrations found in patients with metabolic diseases enhanced the expression of hepatocyte genes associated with lipid synthesis and release, in particular, the fatty acid synthase gene (nearly 20-fold increase in the mRNA level). In contrast, incubation with CPOA2H caused the downregulation of most adipocyte genes associated with lipid synthesis, whereas the level of leptin mRNA was increased. These findings suggest that CPOA2H may contribute to hypertriglyceridemia in patients with metabolic diseases, upregulating the expression of hepatocyte genes responsible for lipid synthesis and release.


Assuntos
Adipócitos/efeitos dos fármacos , Caprilatos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , RNA Mensageiro/genética , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Diferenciação Celular , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Células Hep G2 , Humanos , Leptina/genética , Leptina/metabolismo , Metabolismo dos Lipídeos/genética , Camundongos , Especificidade de Órgãos , PPAR gama/genética , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
19.
Atherosclerosis ; 275: 390-399, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29703634

RESUMO

BACKGROUND AND AIMS: Subendothelial interaction of LDL with extracellular matrix drives atherogenesis. This interaction can be strengthened by proteolytic modification of LDL. Mast cells (MCs) are present in atherosclerotic lesions, and upon activation, they degranulate and release a variety of neutral proteases. Here we studied the ability of MC proteases to cleave apoB-100 of LDL and affect the binding of LDL to proteoglycans. METHODS: Mature human MCs were differentiated from human peripheral blood-derived CD34+ progenitors in vitro and activated with calcium ionophore to generate MC-conditioned medium. LDL was incubated in the MC-conditioned medium or with individual MC proteases, and the binding of native and modified LDL to isolated human aortic proteoglycans or to human atherosclerotic plaques ex vivo was determined. MC proteases in atherosclerotic human coronary artery lesions were detected by immunofluorescence and qPCR. RESULTS: Activated human MCs released the neutral proteases tryptase, chymase, carboxypeptidase A3, cathepsin G, and granzyme B. Of these, cathepsin G degraded most efficiently apoB-100, induced LDL fusion, and enhanced binding of LDL to isolated human aortic proteoglycans and human atherosclerotic lesions ex vivo. Double immunofluoresence staining of human atherosclerotic coronary arteries for tryptase and cathepsin G indicated that lesional MCs contain cathepsin G. In the lesions, expression of cathepsin G correlated with the expression of tryptase and chymase, but not with that of neutrophil proteinase 3. CONCLUSIONS: The present study suggests that cathepsin G in human atherosclerotic lesions is largely derived from MCs and that activated MCs may contribute to atherogenesis by enhancing LDL retention.


Assuntos
Apolipoproteína B-100/metabolismo , Aterosclerose/enzimologia , Doenças das Artérias Carótidas/enzimologia , Catepsina G/metabolismo , Doença da Artéria Coronariana/enzimologia , Lipoproteínas LDL/metabolismo , Mastócitos/enzimologia , Proteoglicanas/metabolismo , Aterosclerose/patologia , Doenças das Artérias Carótidas/patologia , Degranulação Celular , Células Cultivadas , Doença da Artéria Coronariana/patologia , Ativação Enzimática , Humanos , Placa Aterosclerótica , Ligação Proteica , Proteólise
20.
Int J Mol Med ; 42(1): 471-478, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29658561

RESUMO

Atherosclerosis is the main underlying causes of cardiovascular disease. There is a well­established association between high blood cholesterol levels and the extent of atherosclerosis. Furthermore, atherosclerosis has been proposed to augment abdominal aortic aneurysm (AAA) formation. As patients with AAA often have parallel atherosclerotic disease and are therefore often on cholesterol­lowering therapy, it is not possible to fully address the independent effects of plasma cholesterol lowering (PCL) treatment on AAA. The present study investigated the effect of angiotensin II (AngII)­infusion in modestly hypercholesterolemic Ldlr­/­Apob100/100Mttpflox/floxMx1­Cre mice with or without PCL treatment on a morphological and molecular level, in terms of atherosclerosis and AAA development. AngII infusion in the study mice resulted in an increased atherosclerotic lesion area and increased infiltration of inflammatory leukocytes, which was not observed in mice with PCL induced prior to AngII infusion. This suggested that AngII infusion in this mouse model induced atherosclerosis development, and that plasma cholesterol levels represent a controlling factor. Furthermore, AngII infusion in Ldlr­/­Apob100/100Mttpflox/floxMx1­Cre mice caused a modest aneurysmal phenotype, and no differences in AAA development were observed between the different study groups. However, the fact that modest hypercholesterolemic mice did not develop AAA in a classical aneurysmal model indicated that plasma cholesterol levels are important for disease development.


Assuntos
Aterosclerose/sangue , Aterosclerose/complicações , Colesterol/sangue , Hipercolesterolemia/sangue , Hipercolesterolemia/complicações , Angiotensina II , Animais , Aneurisma da Aorta Abdominal/sangue , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/patologia , Apolipoproteína B-100/metabolismo , Aterosclerose/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipercolesterolemia/genética , Integrases/metabolismo , Masculino , Receptores de LDL/metabolismo
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