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1.
Artigo em Inglês | MEDLINE | ID: mdl-32919080

RESUMO

We have reported that acrolein-conjugated low-density lipoprotein (Acro-LDL) uptake by scavenger receptor class A type 1 (SR-A1) can mediate macrophage foam cell formation. The purpose of this study was to determine which amino acid residues of apoB protein in LDL are conjugated with acrolein. Acro-apoB was prepared by incubation of LDL with acrolein (10 to 60 µM) at 37 °C for 7 days. Identification of acrolein-conjugated amino acid residues in apoB was performed using LC-MS/MS. The levels of acrolein-conjugated amino acid residues of apoB as well as crosslinking apoB increased in proportion to acrolein concentration. The level of LDL uptake by macrophages was parallel with the acrolein-conjugated monomer apoB. Acrolein-conjugated amino acid residues in apoB were C212, K327, K742, K949, K1087, H1923, K2634, K3237 and K3846. The NH2-teriminal four amino acid residues (C212, K327, K742 and K949) were located at the scavenger receptor SR-A1 recognition site, suggesting that these four acrolein-conjugated amino acids are involved in the rapid uptake of Acro-LDL by macrophages. It is proposed that the rapid uptake of LDL by macrophages is dependent on acrolein conjugation of four amino acids residues at the scavenger receptor recognition site of apoB in LDL.


Assuntos
Acroleína/química , Apolipoproteína B-100/química , LDL-Colesterol/química , Fatores de Processamento de Serina-Arginina/química , Sequência de Aminoácidos , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Sítios de Ligação , LDL-Colesterol/metabolismo , Expressão Gênica , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Células THP-1
2.
Ecotoxicol Environ Saf ; 207: 111269, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32911180

RESUMO

This study is the first to examine the possible mechanism by which long-term exposure to permethrin (PER) can promote arterial retention of proatherogenic lipid and lipoproteins and related vascular dysfunction in rats. Experimental animals were administered two doses of oral PER, PER-1 (2.5 mg/kg/bw) and PER-2 (5 mg/kg/bw), for 90 consecutive days. The results indicated that both PER-1 and PER-2 increased plasmatic and aortic total cholesterol, low-density lipoprotein cholesterol (LDL-C), apo B-100, and oxidized LDL together with arterial scavenger LDL receptors (CD36) but markedly reduced plasmatic and hepatic high-density lipoprotein cholesterol and native LDL receptors in aortic and hepatic tissue. The levels of malondialdehyde, protein carbonyl, and reactive oxygen species were significantly higher, and glutathione content as well as catalase, superoxide dismutase, and glutathione peroxidase activities were suppressed in the aorta of the PER-1 and PER-2 groups. The arterial oxidative damage possibly caused by PER was clearly demonstrated by hematoxylin and eosin histological analysis. Moreover, PER treatment aggravated the inflammatory responses through enhancement of the production of proinflammatory cytokines (tumor necrosis factor-α, interleukin-2, and interleukin-6) in both plasma and aorta. Furthermore, PER-1 and PER-2 potentiated the dysregulation of the aortic extracellular matrix (ECM) content by increasing mRNA activation of collagens I and III. The abundant histological collagen deposition observed in the media and adventitia of intoxicated rats using Masson's trichrome staining corroborates the observed change in ECM. These data showed that oxidative stress related to PER exposure increases the arterial accumulation of lipoprotein biomarkers, likely by actions on both LDL and CD36 receptors, together with the disruption of the aortic ECM.


Assuntos
Colágeno/genética , Inseticidas/toxicidade , Lipoproteínas LDL/sangue , Estresse Oxidativo/fisiologia , Permetrina/toxicidade , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteína B-100/metabolismo , Antígenos CD36/metabolismo , Inflamação/metabolismo , Lipídeos/sangue , Masculino , Malondialdeído/metabolismo , Oxirredução , Ratos , Espécies Reativas de Oxigênio/metabolismo , Receptores de LDL/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
Nat Commun ; 11(1): 3067, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546794

RESUMO

Lipid transport and ATP synthesis are critical for the progression of non-alcoholic fatty liver disease (NAFLD), but the underlying mechanisms are largely unknown. Here, we report that the RNA-binding protein HuR (ELAVL1) forms complexes with NAFLD-relevant transcripts. It associates with intron 24 of Apob pre-mRNA, with the 3'UTR of Uqcrb, and with the 5'UTR of Ndufb6 mRNA, thereby regulating the splicing of Apob mRNA and the translation of UQCRB and NDUFB6. Hepatocyte-specific HuR knockout reduces the expression of APOB, UQCRB, and NDUFB6 in mice, reducing liver lipid transport and ATP synthesis, and aggravating high-fat diet (HFD)-induced NAFLD. Adenovirus-mediated re-expression of HuR in hepatocytes rescues the effect of HuR knockout in HFD-induced NAFLD. Our findings highlight a critical role of HuR in regulating lipid transport and ATP synthesis.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Proteína Semelhante a ELAV 1/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Trifosfato de Adenosina/biossíntese , Animais , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Citocromos c/genética , Citocromos c/metabolismo , Proteína Semelhante a ELAV 1/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/genética , Homeostase , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Precursores de RNA
4.
Oncol Res Treat ; 43(7-8): 340-345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32554963

RESUMO

BACKGROUND: The aim of this study was to assess the prognostic value of the preoperative apolipoprotein B (ApoB) level in surgical patients with clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS: The study included 307 ccRCC patients receiving radical or partial nephrectomy between 2003 and 2012 in our center. The correlations among the preoperative ApoB, clinicopathological parameters, and overall survival (OS) were evaluated. RESULTS: A total of 193 males (62.9%) and 114 females (37.1%) with ccRCC who underwent radical or partial nephrectomy were enrolled in the present study. The OS at 5 years after the operation was 90.6% for all patients, 87.4% for the lower ApoB group, and 97.0% for the higher-ApoB group. The cause-specific survival (CSS) at 5 years after surgery was 90.2% for all patients, 86.7% for the lower-ApoB group, and 97.0% for the higher-ApoB group. A higher-ApoB level was related to a better OS and CSS in ccRCC patients (p = 0.001 and p < 0.001, respectively). In multivariate analysis, age >60 years (p = 0.008 and p = 0.023) and a lower Apo B level (p = 0.019 and p = 0.018) were independent prognostic factors for OS and CSS, respectively. CONCLUSIONS: In the Apo apolipoprotein family, the preoperative ApoB level had an important clinical significance for predicting the prognosis and survival rate of ccRCC patients.


Assuntos
Apolipoproteína B-100/metabolismo , Biomarcadores Tumorais/sangue , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Nefrectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Neoplasias Renais/sangue , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Taxa de Sobrevida , Adulto Jovem
5.
Int J Mol Sci ; 21(4)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093271

RESUMO

Clinical phenotypes of familial hypobetalipoproteinemia (FHBL) are related to a number of defective apolipoprotein B (APOB) alleles. Fatty liver disease is a typical manifestation, but serious neurological symptoms can appear. In this study, genetic analysis of the APOB gene and ophthalmological diagnostics were performed for family members with FHBL. Five relatives with FHBL, including a proband who developed neurological disorders, were examined. A sequencing analysis of the whole coding region of the APOB gene, including flanking intronic regions, was performed using the next-generation sequencing (NGS) method. Electrophysiological ophthalmological examinations were also done. In the proband and his affected relatives, NGS identified the presence of the pathogenic, rare heterozygous splicing variant c.3696+1G>T. Two known heterozygous missense variants-c.2188G>A, p.(Val730Ile) and c.8353A>C, p.(Asn2785His)-in the APOB gene were also detected. In all patients, many ophthalmologic abnormalities in electrophysiological tests were also found. The identified splicing variant c.3696+1G>T can be associated with observed autosomal, dominant FHBL with coexisting neurological symptoms, and both identified missense variants could be excluded as the main cause of observed clinical signs, according to mutation databases and the literature. Electroretinography examination is a sensitive method for the detection of early neuropathy and should therefore be recommended for the care of patients with FHBL.


Assuntos
Apolipoproteína B-100 , Hipobetalipoproteinemia Familiar por Apolipoproteína B , Mutação de Sentido Incorreto , Doenças do Sistema Nervoso , Processamento de RNA , Adulto , Idoso , Substituição de Aminoácidos , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hipobetalipoproteinemia Familiar por Apolipoproteína B/diagnóstico por imagem , Hipobetalipoproteinemia Familiar por Apolipoproteína B/genética , Hipobetalipoproteinemia Familiar por Apolipoproteína B/metabolismo , Masculino , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo
6.
Biomater Sci ; 8(2): 586-590, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31913375

RESUMO

While siRNA is a potent therapeutic tool that can silence disease-causing mRNA, its in vivo potency can be compromised due to the lack of target tissue specificity. Here, we report a wireframe tetrahedral DNA nanostructure having a 20-mer duplex on each side that can be specifically distributed into the liver upon systemic administration. This liver-targeted DNA tetrahedron is employed as the carrier for liver-specific delivery of siRNA targeting ApoB1 mRNA, which is overexpressed in hypercholesterolemia. When delivered by a DNA tetrahedron, the siRNA can preferentially be accumulated in the liver and down-regulate the ApoB1 protein. As a result, the blood cholesterol level is also decreased by the siRNA. These results successfully demonstrate that the DNA tetrahedron is a promising carrier for liver-targeted delivery of therapeutic nucleic acids.


Assuntos
Apolipoproteína B-100/antagonistas & inibidores , DNA/química , Sistemas de Liberação de Medicamentos , Hipercolesterolemia/tratamento farmacológico , Fígado/química , Nanoestruturas/química , RNA Interferente Pequeno/farmacologia , Animais , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Portadores de Fármacos/química , Células Hep G2 , Humanos , Hipercolesterolemia/genética , Hipercolesterolemia/metabolismo , Fígado/metabolismo , Camundongos , RNA Interferente Pequeno/química
7.
Nucleic Acids Res ; 48(1): 63-74, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31754711

RESUMO

The introduction of non-bridging phosphorothioate (PS) linkages in oligonucleotides has been instrumental for the development of RNA therapeutics and antisense oligonucleotides. This modification offers significantly increased metabolic stability as well as improved pharmacokinetic properties. However, due to the chiral nature of the phosphorothioate, every PS group doubles the amount of possible stereoisomers. Thus PS oligonucleotides are generally obtained as an inseparable mixture of a multitude of diastereoisomeric compounds. Herein, we describe the introduction of non-chiral 3' thiophosphate linkages into antisense oligonucleotides and report their in vitro as well as in vivo activity. The obtained results are carefully investigated for the individual parameters contributing to antisense activity of 3' and 5' thiophosphate modified oligonucleotides (target binding, RNase H recruitment, nuclease stability). We conclude that nuclease stability is the major challenge for this approach. These results highlight the importance of selecting meaningful in vitro experiments particularly when examining hitherto unexplored chemical modifications.


Assuntos
Apolipoproteína B-100/genética , Oligonucleotídeos/genética , Fosfatos/química , Oligonucleotídeos Fosforotioatos/genética , RNA Longo não Codificante/genética , Animais , Apolipoproteína B-100/antagonistas & inibidores , Apolipoproteína B-100/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Rim/citologia , Rim/metabolismo , Fígado/citologia , Fígado/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Oligonucleotídeos/síntese química , Oligonucleotídeos/metabolismo , Fosfatos/metabolismo , Oligonucleotídeos Fosforotioatos/síntese química , Oligonucleotídeos Fosforotioatos/metabolismo , Estabilidade de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/metabolismo , Ribonuclease H/química , Ribonuclease H/metabolismo , Estereoisomerismo
8.
Biochem J ; 476(23): 3565-3581, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31746967

RESUMO

Glycero-lysophospholipids, such as lysophosphatidic acids and lysophosphatidylserine, are gathering attention, since specific receptors have been identified. Most of these compounds have been proposed to be bound to albumin, while their associations with lipoproteins have not been fully elucidated. Therefore, in this study, we aimed to investigate the contents of glycero-lysophospholipids (lysophosphatidic acids, lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylglycerol, lysophosphatidylinositol, and lysophosphatidylserine) on lipoproteins and the modulation of their metabolism by lipoprotein metabolism. We observed that moderate amounts of glycero-lysophospholipids, with the exception of lysophosphatidylserine, were distributed on the LDL and HDL fractions, and glycero-lysophospholipids that had bound to albumin were observed in lipoprotein fractions when they were co-incubated. The overexpression of cholesteryl ester transfer protein decreased the plasma levels of lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylglycerol, and lysophosphatidylinositol and it increased their contents in apoB-containing lipoproteins, while it decreased their contents in HDL and lipoprotein-depleted fractions in mice. The overexpression of the LDL receptor (LDLr) decreased the plasma levels of lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylglycerol, and lysophosphatidylinositol and decreased the contents of these compounds in the LDL, HDL, and lipoprotein-depleted fractions, while the knockdown of the LDLr increased them. These results suggest the potential importance of glycero-lysophospholipids in the pleiotropic effects of lipoproteins as well as the importance of lipoprotein metabolism in the regulation of glycero-lysophospholipids.


Assuntos
Dislipidemias/sangue , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Lisofosfolipídeos/sangue , Animais , Apolipoproteína B-100/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/genética , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Vetores Genéticos , Voluntários Saudáveis , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de LDL/genética , Receptores de LDL/metabolismo , Albumina Sérica/metabolismo
9.
Atherosclerosis ; 290: 111-117, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31605876

RESUMO

Cholesterol homeostasis is of central importance for life. Therefore, cells have developed a divergent set of pathways to meet their cholesterol needs. In this review, we focus on the direct transfer of cholesterol from lipoprotein particles to the cell membrane. More molecular details on the transfer of lipoprotein-derived lipids were gained by recent studies using phospholipid bilayers. While amphiphilic lipids are transferred right after contact of the lipoprotein particle with the membrane, the transfer of core lipids is restricted. Amphiphilic lipid transfer gains special importance in genetic diseases impairing lipoprotein metabolism like familial hypercholesterolemia. Taken together, these data indicate that there is a constant exchange of amphiphilic lipids between lipoprotein particles and the cell membrane.


Assuntos
Membrana Celular/metabolismo , Colesterol/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Apolipoproteína B-100/metabolismo , Transporte Biológico , Colesterol/sangue , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Endocitose , Humanos , Receptores de LDL/metabolismo , Receptores Depuradores Classe B/metabolismo
10.
J Med Food ; 22(11): 1110-1117, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31613687

RESUMO

This study was carried out to investigate the effects of policosanol on high-fat and high-cholesterol diet-induced hypercholesterolemic rats to provide strong evidence in support of its hypocholesterolemic effect. The hypercholesterolemic rats showed elevations in liver weight, total triglycerides, total cholesterol, and low-density lipoprotein (LDL) cholesterol in serum; however, policosanol supplementation reduced these markers significantly. In addition, we found that policosanol supplementation stimulated an increase in fecal cholesterol and bile acid contents and deactivated 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase by AMP-activated protein kinase (AMPK) phosphorylation during high-fat and high-cholesterol-containing diet-induced development of hypercholesterolemia. Policosanol supplementation decreased ApoB levels and increased LDL-receptor expression, but it did not affect the hepatic ACAT2 level in livers from hypercholesterolemic rats. Moreover, supplementation with policosanol significantly decreased aortic wall thickness and levels of P-selectin and soluble vascular cell adhesion molecule (sVCAM-1) in serum. In conclusion, we suggest that policosanol supplementation induces antihypercholesterolemia by inhibiting cholesterol biosynthesis, LDL cholesterol uptake, and cholesterol excretion.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Anticolesterolemiantes/farmacologia , Colesterol/biossíntese , Álcoois Graxos/farmacologia , Hipercolesterolemia/tratamento farmacológico , Animais , Aorta , Apolipoproteína B-100/metabolismo , HDL-Colesterol/sangue , Dieta Hiperlipídica , Hidroximetilglutaril-CoA Redutases/metabolismo , Hipercolesterolemia/enzimologia , Fígado/metabolismo , Masculino , Selectina-P/sangue , Ratos , Ratos Sprague-Dawley , Receptores de LDL/metabolismo , Esterol O-Aciltransferase/metabolismo , Triglicerídeos/sangue , Molécula 1 de Adesão de Célula Vascular/sangue
11.
Mol Genet Genomic Med ; 7(9): e931, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31397093

RESUMO

BACKGROUND: Male EBP disorder with neurologic defects (MEND) syndrome is an X-linked disease caused by hypomorphic mutations in the EBP (emopamil-binding protein) gene. Modifier genes may explain the clinical variability among individuals who share a primary mutation. METHODS: We studied four males (Patient 1 to Patient 4) exhibiting a descending degree of phenotypic severity from a family with MEND syndrome. To identify candidate modifier genes that explain the phenotypic variability, variants of homeostasis cholesterol genes identified by whole-exome sequencing (WES) were ranked according to the predicted magnitude of their effect through an in-house scoring system. RESULTS: Twenty-seven from 105 missense variants found in 45 genes of the four exomes were considered significant (-5 to -9 scores). We found a direct genotype-phenotype association based on the differential accumulation of potentially functional gene variants among males. Patient 1 exhibited 17 variants, both Patients 2 and 3 exhibited nine variants, and Patient 4 exhibited only five variants. CONCLUSION: We conclude that APOA5 (rs3135506), ABCA1 (rs9282541), and APOB (rs679899 and rs12714225) are the most relevant candidate modifier genes in this family. Relative accumulation of the deficiencies associated with variants of these genes along with other lesser deficiencies in other genes appears to explain the variable expressivity in MEND syndrome.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Apolipoproteína A-V , Apolipoproteína B-100 , Colesterol , Exoma , Polimorfismo Genético , Síndrome de Waardenburg , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Apolipoproteína A-V/genética , Apolipoproteína A-V/metabolismo , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Colesterol/genética , Colesterol/metabolismo , Feminino , Estudos de Associação Genética , Homeostase/genética , Humanos , Masculino , Fenótipo , Índice de Gravidade de Doença , Síndrome de Waardenburg/genética , Síndrome de Waardenburg/metabolismo , Síndrome de Waardenburg/patologia
12.
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
13.
J Nutr Biochem ; 70: 75-81, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176989

RESUMO

Lipid metabolism is dependent on riboflavin status. Apolipoprotein B100 plays an important role in lipids transportation. This study was aimed to investigate the effect of riboflavin status on lipid metabolism and explore its association with apolipoprotein B100 synthesis in vivo. Riboflavin deficiency was developed in rats by feeding riboflavin-deficient diets. Compared to the control rats, the mRNA and protein expressions of apolipoprotein B100 were significantly reduced in riboflavin-deficient rats. Endoplasmic reticulum oxidoreductin 1 (ERO1) and protein disulfide isomerase (PDI), two enzymes involved in the oxidative folding of apolipoprotein B100, were also lowered remarkably in expression at protein level. Meanwhile, total cholesterol and triglyceride levels were decreased in the plasma and increased in the liver of riboflavin-deficient rats. The plasma very low-density lipoprotein cholesterol (VLDL-c) and low-density lipoprotein cholesterol (LDL-c) were also reduced in riboflavin-deficient rats. Our findings demonstrate that riboflavin deficiency affects lipid metabolism partly by reducing apolipoprotein B100 synthesis.


Assuntos
Apolipoproteína B-100/metabolismo , Metabolismo dos Lipídeos , Deficiência de Riboflavina/metabolismo , Animais , Colesterol/química , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Fígado/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Estresse Oxidativo , Isomerases de Dissulfetos de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Riboflavina/metabolismo , Triglicerídeos/química
14.
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
15.
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
16.
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
17.
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
18.
J Intern Med ; 285(5): 562-577, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30779243

RESUMO

BACKGROUND: Triglyceride-rich lipoproteins and their remnants have emerged as major risk factors for cardiovascular disease. New experimental approaches are required that permit simultaneous investigation of the dynamics of chylomicrons (CM) and apoB48 metabolism and of apoB100 in very low-density lipoproteins (VLDL). METHODS: Mass spectrometric techniques were used to determine the masses and tracer enrichments of apoB48 in the CM, VLDL1 and VLDL2 density intervals. An integrated non-steady-state multicompartmental model was constructed to describe the metabolism of apoB48- and apoB100-containing lipoproteins following a fat-rich meal, as well as during prolonged fasting. RESULTS: The kinetic model described the metabolism of apoB48 in CM, VLDL1 and VLDL2 . It predicted a low level of basal apoB48 secretion and, during fat absorption, an increment in apoB48 release into not only CM but also directly into VLDL1 and VLDL2 . ApoB48 particles with a long residence time were present in VLDL, and in subjects with high plasma triglycerides, these lipoproteins contributed to apoB48 measured during fasting conditions. Basal apoB48 secretion was about 50 mg day-1 , and the increment during absorption was about 230 mg day-1 . The fractional catabolic rates for apoB48 in VLDL1 and VLDL2 were substantially lower than for apoB48 in CM. DISCUSSION: This novel non-steady-state model integrates the metabolic properties of both apoB100 and apoB48 and the kinetics of triglyceride. The model is physiologically relevant and provides insight not only into apoB48 release in the basal and postabsorptive states but also into the contribution of the intestine to VLDL pool size and kinetics.


Assuntos
Apolipoproteína B-100/metabolismo , Apolipoproteína B-48/metabolismo , Modelos Biológicos , Adulto , Humanos , Cinética , Lipoproteínas VLDL/metabolismo , Masculino , Pessoa de Meia-Idade
19.
J Hepatol ; 70(4): 626-638, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30553840

RESUMO

BACKGROUND & AIMS: In the sera of infected patients, hepatitis C virus (HCV) particles display heterogeneous forms with low-buoyant densities (<1.08), underscoring their lipidation via association with apoB-containing lipoproteins, which was proposed to occur during assembly or secretion from infected hepatocytes. However, the mechanisms inducing this association remain poorly-defined and most cell culture grown HCV (HCVcc) particles exhibit higher density (>1.08) and poor/no association with apoB. We aimed to elucidate the mechanisms of lipidation and to produce HCVcc particles resembling those in infected sera. METHODS: We produced HCVcc particles of Jc1 or H77 strains from Huh-7.5 hepatoma cells cultured in standard conditions (10%-fetal calf serum) vs. in serum-free or human serum conditions before comparing their density profiles to patient-derived virus. We also characterized wild-type and Jc1/H77 hypervariable region 1 (HVR1)-swapped mutant HCVcc particles produced in serum-free media and incubated with different serum types or with purified lipoproteins. RESULTS: Compared to serum-free or fetal calf serum conditions, production with human serum redistributed most HCVcc infectious particles to low density (<1.08) or very-low density (<1.04) ranges. In addition, short-time incubation with human serum was sufficient to shift HCVcc physical particles to low-density fractions, in time- and dose-dependent manners, which increased their specific infectivity, promoted apoB-association and induced neutralization-resistance. Moreover, compared to Jc1, we detected higher levels of H77 HCVcc infectious particles in very-low-density fractions, which could unambiguously be attributed to strain-specific features of the HVR1 sequence. Finally, all 3 lipoprotein classes, i.e., very-low-density, low-density and high-density lipoproteins, could synergistically induce low-density shift of HCV particles; yet, this required additional non-lipid serum factor(s) that include albumin. CONCLUSIONS: The association of HCV particles with lipids may occur in the extracellular milieu. The lipidation level depends on serum composition as well as on HVR1-specific properties. These simple culture conditions allow production of infectious HCV particles resembling those of chronically-infected patients. LAY SUMMARY: Hepatitis C virus (HCV) particles may associate with apoB and acquire neutral lipids after exiting cells, giving them low-buoyant density. The hypervariable region 1 (HVR1) is a majorviral determinant of E2 that controls this process. Besides lipoproteins, specific serum factors including albumin promote extracellular maturation of HCV virions. HCV particle production in vitro, with media of defined serum conditions, enables production of infectious particles resembling those of chronically infected patients.


Assuntos
Apolipoproteína B-100/metabolismo , Líquido Extracelular/metabolismo , Hepacivirus/metabolismo , Hepatite C/metabolismo , Albumina Sérica Humana/metabolismo , Vírion/metabolismo , Apolipoproteínas E/metabolismo , Linhagem Celular Tumoral , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , VLDL-Colesterol/metabolismo , Meios de Cultivo Condicionados , Meios de Cultura Livres de Soro , Hepatite C/virologia , Hepatócitos/metabolismo , Hepatócitos/virologia , Humanos , Proteínas do Envelope Viral/química , Proteínas Virais/metabolismo , Montagem de Vírus
20.
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
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