RESUMO
INTRODUCTION: This study aims to investigate if a mixture of functional lipids (FLs), containing conjugated linoleic acid (CLA), tocopherols (TPs), and phytosterols (PSs), prevents some lipid alterations induced by high-fat (HF) diets, without adverse effects. METHODS: Male CF1 mice (n = 6/group) were fed (4 weeks) with control (C), HF, or HF + FL diets. RESULTS: FL prevented the overweight induced by the HF diet and reduced the adipose tissue (AT) weight, associated with lower energy efficiency. After the intervention period, the serum triacylglycerol (TAG) levels in both HF diets underwent a decrease associated with an enhanced LPL activity (mainly in muscle). The beneficial effect of the FL mixture on body weight gain and AT weight might be attributed to the decreased lipogenesis, denoted by the lower mRNA levels of SREBP1-c and ACC in AT, as well as by an exacerbated lipid catabolism, reflected by increased mRNA levels of PPARα, ATGL, HSL, and UCP2 in AT. Liver TAG levels were reduced in the HF + FL group due to an elevated lipid oxidation associated with a higher CPT-1 activity and mRNA levels of PPARα and CPT-1a. Moreover, genes linked to fatty acid biosynthesis (SREBP1-c and ACC) showed decreased mRNA levels in both HF diets, this finding being more pronounced in the HF + FL group. CONCLUSION: The administration of an FL mixture (CLA + TP + PS) prevented some lipid alterations induced by a HF diet, avoiding frequent deleterious effects of CLA in mice through the modulation of gene expression related to the regulation of lipid metabolism.
Assuntos
Dieta Hiperlipídica , Ácidos Linoleicos Conjugados , Metabolismo dos Lipídeos , Fígado , PPAR alfa , Proteína de Ligação a Elemento Regulador de Esterol 1 , Triglicerídeos , Animais , Dieta Hiperlipídica/efeitos adversos , Camundongos , Masculino , Triglicerídeos/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , PPAR alfa/metabolismo , PPAR alfa/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Ácidos Linoleicos Conjugados/farmacologia , Lipogênese/efeitos dos fármacos , Carnitina O-Palmitoiltransferase/metabolismo , Carnitina O-Palmitoiltransferase/genética , Proteína Desacopladora 2/metabolismo , Proteína Desacopladora 2/genética , Fitosteróis/farmacologia , Tecido Adiposo/metabolismo , Tecido Adiposo/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos , Lipase Lipoproteica/metabolismo , Lipase Lipoproteica/genéticaRESUMO
OBJECTIVES: This study explored the association of deleterious variants in pharmacodynamics (PD) genes with statin response and adverse effects in patients with familial hypercholesterolemia (FH) and analyzed their potential effects on protein structure and stability. METHODS: Clinical and laboratory data were obtained from 144 adult FH patients treated with statins. A panel of 32 PD genes was analyzed by exon-targeted gene sequencing. Deleterious variants were identified using prediction algorithms and their structural effects were analyzed by molecular modeling studies. RESULTS: A total of 102 variants were predicted as deleterious (83 missense, 8 stop-gain, 4 frameshift, 1 indel, 6 splicing). The variants ABCA1 rs769705621 (indel), LPA rs41267807 (p.Tyr2023Cys) and KIF6 rs20455 (p.Trp719Arg) were associated with reduced low-density lipoprotein cholesterol (LDLc) response to statins, and the LPL rs1801177 (p.Asp36Asn) with increased LDLc response (Pâ <â 0.05). LPA rs3124784 (p.Arg2016Cys) was predicted to increase statin response (Pâ =â 0.022), and ABCA1 rs769705621 to increase the risk of statin-related adverse events (SRAE) (Pâ =â 0.027). LPA p.Arg2016Cys and LPL p.Asn36Asp maintained interactions with solvent, LPA p.Tyr2023Cys reduced intramolecular interaction with Gln1987, and KIF6 p.Trp719Arg did not affect intramolecular interactions. DDMut analysis showed that LPA p.Arg2016Cys and p.Tyr2023Cys and LPL p.Asp36Asn caused energetically favorable changes, and KIF6 p.Trp719Arg resulted in unfavorable energetic changes, affecting protein stability. CONCLUSION: Deleterious variants in ABCA1, LPA, LPL and KIF6 are associated with variability in LDLc response to statins, and ABCA1 rs769705621 is associated with SRAE risk in FH patients. Molecular modeling studies suggest that LPA p.Tyr2023Cys and KIF6 p.Trp719Arg disturb protein conformational structure and stability.
Assuntos
Transportador 1 de Cassete de Ligação de ATP , Inibidores de Hidroximetilglutaril-CoA Redutases , Hiperlipoproteinemia Tipo II , Cinesinas , Lipase Lipoproteica , Humanos , Cinesinas/genética , Masculino , Feminino , Pessoa de Meia-Idade , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Transportador 1 de Cassete de Ligação de ATP/genética , Lipase Lipoproteica/genética , Adulto , Estabilidade Proteica , LDL-Colesterol/sangue , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Objective: The study aims to explore the relationship between lipoprotein lipase (LPL) variants and hyperlipidemic acute pancreatitis (HLAP) in the southeastern Chinese population. Subjects and methods: In total, 80 participants were involved in this study (54 patients with HLAP and 26 controls). All coding regions and intron-exon boundaries of the LPL gene were sequenced. The correlations between variants and phenotypes were also analysed. Results: The rate of rare LPL variants in the HLAP group is 14.81% (8 of 54), higher than in controls. Among the detected four variants (rs3735959, rs371282890, rs761886494 and rs761265900), the most common variant was rs371282890. Further analysis demonstrated that subjects with rs371282890 "GC" genotype had a 2.843-fold higher risk for HLAP (odds ratio [OR]: 2.843, 95% confidence interval [CI]: 1.119-7.225, p = 0.028) than subjects with the "CC" genotype. After adjusting for sex, the association remained significant (adjusted OR: 3.083, 95% CI: 1.208-7.869, p = 0.018). Subjects with rs371282890 "GC" genotype also exhibited significantly elevated total cholesterol, triglyceride and non-high-density lipoprotein cholesterol levels in all the participants and the HLAP group (p < 0.05). Conclusion: Detecting rare variants in LPL might be valuable for identifying higher-risk patients with HLAP and guiding future individualised therapeutic strategies.
Assuntos
Pancreatite , Humanos , Doença Aguda , China/epidemiologia , Genótipo , Lipase Lipoproteica/genética , Pancreatite/diagnóstico , Pancreatite/genética , TriglicerídeosRESUMO
BACKGROUND AND AIM: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive metabolic disorder caused by mutations in genes involved in chylomicron metabolism. On the other hand, multifactorial chylomicronemia syndrome (MCS) is a polygenic disorder and the most frequent cause of chylomicronemia, which results from the presence of multiple genetic variants related to chylomicron metabolism, in addition to secondary factors. Indeed, the genetic determinants that predispose to MCS are the presence of a heterozygous rare variant or an accumulation of several SNPs (oligo/polygenic). However, their clinical, paraclinical, and molecular features are not well established in our country. The objective of this study was to describe the development and results of a screening program for severe hypertriglyceridemia in Colombia. METHODS: A cross-sectional study was performed. All patients aged >18 years with triglyceride levels ≥500 mg/dL from 2010 to 2020 were included. The program was developed in three stages: 1. Review of electronic records and identification of suspected cases based on laboratory findings (triglyceride levels ≥500 mg/dL); 2. Identification of suspected cases based on laboratory findings that also allowed us to exclude secondary factors; 3. Patients with FCS scores <8 were excluded. The remaining patients underwent molecular analysis. RESULTS: In total, we categorized 2415 patients as suspected clinical cases with a mean age of 53 years, of which 68% corresponded to male patients. The mean triglyceride levels were 705.37 mg/dL (standard deviation [SD] 335.9 mg/dL). After applying the FCS score, 2.4% (n = 18) of patients met the probable case definition and underwent a molecular test. Additionally, 7 patients had unique variants in the APOA5 gene (c.694 T > C; p. Ser232Pro) or in the GPIHBP1 gene (c.523G > C; p. Gly175Arg), for an apparent prevalence of familial chylomicronemia in the consulting population of 0.41 per 1.000 patients with severe HTG measurement. No previously reported pathogenic variants were detected. CONCLUSION: This study describes a screening program for the detection of severe hypertriglyceridemia. Although we identified seven patients as carriers of a variant in the APOA5 gene, we diagnosed only one patient with FCS. We believe that more programs of these characteristics should be developed in our region, given the importance of early detection of this metabolic disorder.
Assuntos
Hiperlipoproteinemia Tipo IV , Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Humanos , Masculino , Pessoa de Meia-Idade , Hiperlipoproteinemia Tipo I/diagnóstico , Hiperlipoproteinemia Tipo I/genética , Estudos Transversais , Lipase Lipoproteica/genética , Colômbia/epidemiologia , Hipertrigliceridemia/epidemiologia , Hipertrigliceridemia/genética , Hipertrigliceridemia/complicações , Triglicerídeos , QuilomícronsRESUMO
Familial chylomicronemia syndrome (FCS) is a genetic entity with autosomal recessive inheritance. Mutations in genes (such as APOC2, APOAV, LMF-1, GPIHBP-1) that code for proteins that regulate the maturation, transport, or polymerization of lipoprotein lipase-1 are the most common causes, but not the only ones. The objective of this study was to report the first documented case in Ecuador. CLINICAL CASE: A 38-year-old man presented with chronic hepatosplenomegaly, thrombocytopenia, pancreatic atrophy, and severe hypertriglyceridemia refractory to treatment. A molecular analysis was performed by next generation sequencing that determined a deficiency of Lipoprotein Lipase OMIM #238600 in homozygosis. Genetic confirmation is necessary in order to establish the etiology of HTGS for an adequate management of this pathology.
Assuntos
Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Humanos , Masculino , Adulto , Hiperlipoproteinemia Tipo I/diagnóstico , Hiperlipoproteinemia Tipo I/genética , Hiperlipoproteinemia Tipo I/metabolismo , Lipase Lipoproteica/genética , Equador , Hipertrigliceridemia/etiologiaRESUMO
Rare pathogenic variants in the LMF1 gene, which encodes lipase maturation factor 1, are a minor cause of familial chylomicronemia syndrome (FCS) and severe hypertriglyceridemia. In this report we present three adult patients, all of them born and raised in Quito, Ecuador, with severe hypertriglyceridemia secondary to biallelic LMF1 variants. In two of the three cases (patients 1 and 3), the presentation was acute pancreatitis secondary to plasma triglycerides well above 10 mmol/L. The other case (patient 2) was a sibling of one of the initial patients, who was asymptomatic but markedly hypertriglyceridemic. Next-generation sequencing revealed a homozygous splice-site variant in exon 6 of LMF1 in patients 1 and 2 (c.897G>A, p.Gln299=), and a homozygous missense variant in exon 2 of LMF1 in patient 3 (c.233T>C, p.Leu78Pro). The finding of two disease-causing variants in three patients from the same location raises the question of whether LMF1 may be a more prevalent cause of severe hypertriglyceridemia among Latin-American patients.
Assuntos
Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Pancreatite , Doença Aguda , Adulto , Equador , Humanos , Hiperlipoproteinemia Tipo I/genética , Hipertrigliceridemia/complicações , Hipertrigliceridemia/genética , Lipase Lipoproteica/genética , Proteínas de Membrana/genética , Pancreatite/complicaçõesRESUMO
Primary hypertriglyceridemia (PHTG) is characterized by a high concentration of triglycerides (TG); it is divided between familial hyperchylomicronemia syndrome and multifactorial chylomicronemia syndrome. In Mexico, hypertriglyceridemia constitutes a health problem in which the genetic bases have been scarcely explored; therefore, our objective was to describe biochemical-clinical characteristics and variants in the APOA5, GPIHBP1, LMF1, and LPL genes in patients with primary hypertriglyceridemia. Thirty DNA fragments were analyzed using PCR and Sanger sequencing in 58 unrelated patients. The patients' main clinical-biochemical features were hypoalphalipoproteinemia (77.6%), pancreatitis (18.1%), and a TG median value of 773.9 mg/dL. A total of 74 variants were found (10 in APOA5, 16 in GPIHBP1, 34 in LMF1, and 14 in LPL), of which 15 could be involved in the development of PHTG: 3 common variants with significative odds and 12 heterozygous rare pathogenic variants distributed in 12 patients. We report on the first Mexican patient with hyperchylomicronemia syndrome due to GPIHBP1 deficiency caused by three variants: p.R145*, p.A154_G155insK, and p.A154Rfs*152. Moreover, eleven patients were heterozygous for the rare variants described as causing PHTG and also presented common variants of risk, which could partially explain their phenotype. In terms of findings, two novel genetic variants, c.-40_-22del LMF1 and p.G242Dfs*10 LPL, were identified.
Assuntos
Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Receptores de Lipoproteínas , Humanos , Lipase Lipoproteica/genética , México , Hiperlipoproteinemia Tipo I/genética , Hiperlipoproteinemia Tipo I/patologia , Hipertrigliceridemia/genética , Triglicerídeos , Receptores de Lipoproteínas/genéticaRESUMO
BACKGROUND AND AIMS: GPIHBP1 is an accessory protein of lipoprotein lipase (LPL) essential for its functioning. Mutations in the GPIHBP1 gene cause a deficit in the action of LPL, leading to severe hypertriglyceridemia and increased risk for acute pancreatitis. METHODS: We describe twelve patients (nine women) with a novel homozygous mutation in intron 2 of the GPIHBP1 gene. RESULTS: All patients were from the Northeastern region of Brazil and presented the same homozygous variant located in a highly conserved 3' splicing acceptor site of the GPIHBP1 gene. This new variant was named c.182-1G > T, according to HGVS recommendations. We verified this new GPIHBP1 variant's effect by using the Human Splicing Finder (HSF) tool. This mutation changes the GPIHBP1 pre-mRNA processing and possibly causes the skipping of the exon 3 of the GPIHBP1 gene, affecting almost 50% of the cysteine-rich Lys6 GPIHBP1 domain. Patients presented with severe hypertriglyceridemia (2351 mg/dl [885-20600]) and low HDL (18 mg/dl [5-41). Four patients (33%) had a previous history of acute pancreatitis. CONCLUSIONS: We describe a novel GPIHBP1 pathogenic intronic mutation of patients from the Northeast region of Brazil, suggesting the occurrence of a founder effect.
Assuntos
Hiperlipoproteinemia Tipo I , Pancreatite , Receptores de Lipoproteínas , Doença Aguda , Brasil , Feminino , Humanos , Hiperlipoproteinemia Tipo I/genética , Lipase Lipoproteica/genética , Masculino , Mutação , Pancreatite/genética , Receptores de Lipoproteínas/genéticaRESUMO
BACKGROUND: Familial hypertriglyceridemia (FHTG) is a partially characterized primary dyslipidemia which is frequently confused with other forms hypertriglyceridemia. The aim of this work is to search for specific features that can help physicians recognize this disease. METHODS: This study included 84 FHTG cases, 728 subjects with common mild-to-moderate hypertriglyceridemia (CHTG) and 609 normotriglyceridemic controls. All subjects underwent genetic, clinical and biochemical assessments. A set of 53 single nucleotide polymorphisms (SNPs) previously associated with triglycerides levels, as well as 37 rare variants within the five main genes associated with hypertriglyceridemia (i.e. LPL, APOC2, APOA5, LMF1 and GPIHBP1) were analyzed. A panel of endocrine regulatory proteins associated with triglycerides homeostasis were compared between the FHTG and CHTG groups. RESULTS: Apolipoprotein B, fibroblast growth factor 21(FGF-21), angiopoietin-like proteins 3 (ANGPTL3) and apolipoprotein A-II concentrations, were independent components of a model to detect FHTG compared with CHTG (AUC 0.948, 95%CI 0.901-0.970, 98.5% sensitivity, 92.2% specificity, P < 0.001). The polygenic set of SNPs, accounted for 1.78% of the variance in triglyceride levels in FHTG and 6.73% in CHTG. CONCLUSIONS: The clinical and genetic differences observed between FHTG and CHTG supports the notion that FHTG is a unique entity, distinguishable from other causes of hypertriglyceridemia by the higher concentrations of insulin, FGF-21, ANGPTL3, apo A-II and lower levels of apo B. We propose the inclusion of these parameters as useful markers for differentiating FHTG from other causes of hypertriglyceridemia.
Assuntos
Proteínas Semelhantes a Angiopoietina/genética , Apolipoproteína A-II/genética , Fatores de Crescimento de Fibroblastos/genética , Hiperlipoproteinemia Tipo IV/diagnóstico , Hipertrigliceridemia/diagnóstico , Adulto , Proteína 3 Semelhante a Angiopoietina , Apolipoproteína A-V/genética , Apolipoproteína C-II/genética , Apolipoproteínas B/genética , Diagnóstico Diferencial , Feminino , Humanos , Hiperlipoproteinemia Tipo IV/genética , Hiperlipoproteinemia Tipo IV/metabolismo , Hiperlipoproteinemia Tipo IV/patologia , Hipertrigliceridemia/genética , Hipertrigliceridemia/metabolismo , Hipertrigliceridemia/patologia , Insulina/genética , Lipase Lipoproteica/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Receptores de Lipoproteínas/genética , Triglicerídeos/genéticaRESUMO
Chronic low-grade inflammation is strongly related to the etiology of diabetes mellitus type 2 (T2DM), and the expression of inflammatory cytokines may be modulated by polymorphisms located in the regulatory regions of the NFκß, IL-1ß, IL-6, TNFα, and LPL genes. We considered it particularly important to investigate the relationship of gene polymorphisms involved in chronic inflammation with the risk of T2DM or uncontrolled biochemical parameters. METHODS: We included 199 individuals with a T2DM diagnosis and 213 individuals without a T2DM diagnosis. Restriction fragment length polymorphism (RFLP) analyses were used to assess polymorphisms. RESULTS: We found a risk association between T2DM and uncontrolled biochemical parameters in a Mexican population for the genotypes del/del of NFκß, -174 and -572 of IL-6, C/C of IL-1ß, -308 and -238 of TNFα, and T/T of LPL. In subjects without diabetes (controls), we found an association between the G/C genotype of the -572 polymorphism and the G/C and C/C genotypes of the -597 polymorphism of IL-6 with the risk of glucose levels > 131 mg/dL. Genotype C/C of polymorphism -174 of the IL-6 gene was associated with high triglyceride levels, and levels > 5.8% of HbA1c were associated with the G/A genotype of TNFα -308. CONCLUSION: Here, we describe for the first time the relationship of T2DM risk and uncontrolled biochemical parameters with polymorphisms in the NFκß, IL-6, TNFα, IL-1ß, and LPL genes in a Mexican population. We also showed that for the population included in this study, there is an additive effect of the polymorphisms of the studied genes that considerably increases the risk of developing T2DM.We also showed that there are interactions between genes related to chronic inflammation that affect the risk of T2DM.