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1.
medRxiv ; 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37162948

RESUMO

Objective: Considering the non-specific nature of muscle symptoms, studies of statin-induced myopathy (SIM) in electronic health records require accurate algortihms that can reliably identify true statin-related cases. However, prior algorithms have been constructed in study populations that preclude broad applicability. Here we developed and validated an algorithm that accurately defines SIM from electronic health records using structured data elements and conducted a study of determinants of SIM after applying the algorithm. Materials and Methods: We used electronic records from an integrated health care delivery system (including comprehensive pharmacy dispensing records) and defined SIM as elevated creatine kinase (CK) ≥4 x upper limit of normal. A diverse cohort of participants receiving a variety of statin regimens met the criteria for study inclusion. Results: We identified multiple conditions strongly associated with elevated CK independent of statin use. A 2-step algorithm was developed using these all-cause conditions as secondary causes (step 1) along with evidence of a statin regimen change (step 2). We identified 1,262 algorithm-derived statin-induced elevated CK cases. Gold standard SIM cases determined from manual chart reviews on a random subset of the all-cause elevated CK cases were used to validate the algorithm, which had a 76% sensitivity and 77% specificity for detecting the most certain cases. Pravastatin use was associated with a 2.18 odds (95% confidence interval 1.39-3.40, P=0.0007) for statin-induced CK elevation compared to lovastatin use after adjusting for dose and other factors. Conclusions: We have produced an efficient, easy-to-apply methodological tool that can improve the quality of future research on statin-induced myopathy.

2.
Nutrients ; 13(6)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198888

RESUMO

BACKGROUND: Foods rich in saturated fatty acids (SFAs) have been discouraged by virtue of their cholesterol-raising potential, but this effect is modulated by the food source and background level of carbohydrate. OBJECTIVE: We aimed to compare the consumption of palm stearin (PS) versus butter on circulating cholesterol responses in the setting of both a low-carbohydrate/high-fat (LC/HF) and high-carbohydrate/low-fat (HC/LF) diet in healthy subjects. We also explored effects on plasma lipoprotein particle distribution and fatty acid composition. METHODS: We performed a randomized, controlled-feeding, cross-over study that compared a PS- versus a Butter-based diet in a group of normocholesterolemic, non-obese adults. A controlled canola oil-based 'Run-In' diet preceded the experimental PS and Butter diets. All diets were eucaloric, provided for 3-weeks, and had the same macronutrient distribution but varied in primary fat source (40% of the total fat). The same Run-In and cross-over experiments were done in two separate groups who self-selected to either a LC/HF (n = 12) or a HC/LF (n = 12) diet track. The primary outcomes were low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein (HDL)-C, triglycerides, and LDL particle distribution. RESULTS: Compared to PS, Butter resulted in higher LDL-C in both the LC/HF (13.4%, p = 0.003) and HC/LF (10.8%, p = 0.002) groups, which was primarily attributed to large LDL I and LDL IIa particles. There were no differences between PS and Butter in HDL-C, triglycerides, or small LDL particles. Oxidized LDL was lower after PS than Butter in LC/HF (p = 0.011), but not the HC/LF group. CONCLUSIONS: These results demonstrate that Butter raises LDL-C relative to PS in healthy normocholesterolemic adults regardless of background variations in carbohydrate and fat, an effect primarily attributed to larger cholesterol-rich LDL particles.


Assuntos
Manteiga , Colesterol/sangue , Dieta/métodos , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Óleo de Palmeira/administração & dosagem , Adulto , Idoso , Estudos Cross-Over , Dieta/efeitos adversos , Dieta da Carga de Carboidratos/efeitos adversos , Dieta da Carga de Carboidratos/métodos , Dieta com Restrição de Carboidratos/efeitos adversos , Dieta com Restrição de Carboidratos/métodos , Dieta com Restrição de Gorduras/efeitos adversos , Dieta com Restrição de Gorduras/métodos , Dieta Hiperlipídica/efeitos adversos , Dieta Hiperlipídica/métodos , Feminino , Voluntários Saudáveis , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Óleo de Palmeira/química , Adulto Jovem
3.
PLoS One ; 15(10): e0240437, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33079935

RESUMO

BACKGROUND: Poor diets contribute to metabolic complications of obesity, insulin resistance and dyslipidemia. Metabolomic biomarkers may serve as early nutrition-sensitive health indicators. This family-based lifestyle change program compared metabolic outcomes in an intervention group (INT) that consumed 2 nutrient bars daily for 2-months and a control group (CONT). METHODS: Overweight, predominantly minority and female adolescent (Teen)/parent adult caretaker (PAC) family units were recruited from a pediatric obesity clinic. CONT (8 Teen, 8 PAC) and INT (10 Teen, 10 PAC) groups randomized to nutrient bar supplementation attended weekly classes that included group nutrition counseling and supervised exercise. Pre-post physical and behavioral parameters, fasting traditional biomarkers, plasma sphingolipids and amino acid metabolites were measured. RESULTS: In the full cohort, a baseline sphingolipid ceramide principal component composite score correlated with adiponectin, triglycerides, triglyceride-rich very low density lipoproteins, and atherogenic small low density lipoprotein (LDL) sublasses. Inverse associations were seen between a sphingomyelin composite score and C-reactive protein, a dihydroceramide composite score and diastolic blood pressure, and the final principal component that included glutathionone with fasting insulin and the homeostatic model of insulin resistance. In CONT, plasma ceramides, sphinganine, sphingosine and amino acid metabolites increased, presumably due to increased physical activity. Nutrient bar supplementation (INT) blunted this rise and significantly decreased ureagenic, aromatic and gluconeogenic amino acid metabolites. Metabolomic changes were positively correlated with improvements in clinical biomarkers of dyslipidemia. CONCLUSION: Nutrient bar supplementation with increased physical activity in obese Teens and PAC elicits favorable metabolomic changes that correlate with improved dyslipidemia. The trial from which the analyses reported upon herein was part of a series of nutrient bar clinical trials registered at clinicaltrials.gov as NCT02239198.


Assuntos
Terapia por Exercício/métodos , Metabolômica/métodos , Sobrepeso/terapia , Plasma/química , Adolescente , Adulto , Aconselhamento , Suplementos Nutricionais , Família , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Plasma/efeitos dos fármacos , Resultado do Tratamento
4.
Am J Clin Nutr ; 112(1): 13-18, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32491173

RESUMO

Based on decades of research, there is strong evidence that supports ongoing dietary recommendations to decrease intakes of SFAs and, more recently, to replace SFAs with unsaturated fat, including PUFAs and MUFAs. Epidemiologic research has shown that replacement of SFAs with unsaturated fat, but not refined carbohydrate and added sugars, is associated with a reduction in coronary heart disease events and death. There is much evidence from controlled clinical studies demonstrating that SFAs increase LDL cholesterol, a major causal factor in the development of cardiovascular disease. When each (nonprotein) dietary macronutrient isocalorically replaces SFA, the greatest LDL-cholesterol-lowering effect is seen with PUFA, followed by MUFA, and then total carbohydrate. New research on full-fat dairy products high in saturated fat, particularly fermented dairy foods, demonstrates some benefits for cardiometabolic diseases. However, compared with food sources of unsaturated fats, full-fat dairy products increase LDL cholesterol. Thus, current dietary recommendations to decrease SFA and replace it with unsaturated fat should continue to the basis for healthy food-based dietary patterns.


Assuntos
Gorduras na Dieta/metabolismo , Ácidos Graxos/metabolismo , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/metabolismo , Ácidos Graxos/análise , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/metabolismo , História do Século XXI , Humanos , Saúde Pública/história , Saúde Pública/normas , Ensaios Clínicos Controlados Aleatórios como Assunto , Recomendações Nutricionais/história
5.
J Lipid Res ; 61(3): 376-386, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31919051

RESUMO

Angiopoietin-like protein 3 (ANGPTL3) inhibits lipid clearance and is a promising target for managing cardiovascular disease. Here we investigated the effects of a high-sugar (high-fructose) diet on circulating ANGPTL3 concentrations in rhesus macaques. Plasma ANGPTL3 concentrations increased ∼30% to 40% after 1 and 3 months of a high-fructose diet (both P < 0.001 vs. baseline). During fructose-induced metabolic dysregulation, plasma ANGPTL3 concentrations were positively correlated with circulating indices of insulin resistance [assessed with fasting insulin and the homeostatic model assessment of insulin resistance (HOMA-IR)], hypertriglyceridemia, adiposity (assessed as leptin), and systemic inflammation [C-reactive peptide (CRP)] and negatively correlated with plasma levels of the insulin-sensitizing hormone adropin. Multiple regression analyses identified a strong association between circulating APOC3 and ANGPTL3 concentrations. Higher baseline plasma levels of both ANGPTL3 and APOC3 were associated with an increased risk for fructose-induced insulin resistance. Fish oil previously shown to prevent insulin resistance and hypertriglyceridemia in this model prevented increases of ANGPTL3 without affecting systemic inflammation (increased plasma CRP and interleukin-6 concentrations). ANGPTL3 RNAi lowered plasma concentrations of ANGPTL3, triglycerides (TGs), VLDL-C, APOC3, and APOE. These decreases were consistent with a reduced risk of atherosclerosis. In summary, dietary sugar-induced increases of circulating ANGPTL3 concentrations after metabolic dysregulation correlated positively with leptin levels, HOMA-IR, and dyslipidemia. Targeting ANGPTL3 expression with RNAi inhibited dyslipidemia by lowering plasma TGs, VLDL-C, APOC3, and APOE levels in rhesus macaques.


Assuntos
Proteínas Semelhantes a Angiopoietina/antagonistas & inibidores , Dislipidemias/tratamento farmacológico , Óleos de Peixe/farmacologia , Frutose/antagonistas & inibidores , Interferência de RNA , Proteínas Semelhantes a Angiopoietina/sangue , Proteínas Semelhantes a Angiopoietina/metabolismo , Animais , Suplementos Nutricionais , Dislipidemias/sangue , Dislipidemias/induzido quimicamente , Óleos de Peixe/administração & dosagem , Inflamação/metabolismo , Lipoproteínas/metabolismo , Macaca mulatta , Masculino
6.
J Lipid Res ; 60(4): 805-818, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30723097

RESUMO

Dyslipidemia and insulin resistance are significant adverse outcomes of consuming high-sugar diets. Conversely, dietary fish oil (FO) reduces plasma lipids. Diet-induced dyslipidemia in a rhesus model better approximates the pathophysiology of human metabolic syndrome (MetS) than rodent models. Here, we investigated relationships between metabolic parameters and hypertriglyceridemia in rhesus macaques consuming a high-fructose diet (n = 59) and determined the effects of FO supplementation or RNA interference (RNAi) on plasma ApoC3 and triglyceride (TG) concentrations. Fructose supplementation increased body weight, fasting insulin, leptin, TGs, and large VLDL particles and reduced adiponectin concentrations (all P < 0.001). In multiple regression analyses, increased plasma ApoC3 was the most consistent and significant variable related to diet-induced hypertriglyceridemia. FO supplementation, which attenuated increases of plasma TG and ApoC3 concentrations, reversed fructose-induced shifts of lipoprotein particle size toward IDL and VLDL, a likely mechanism contributing to beneficial metabolic effects, and reduced hepatic expression of genes regulated by the SREBP pathway, particularly acetyl-CoA carboxylase. Furthermore, RNAi-mediated ApoC3 inhibition lowered plasma TG concentrations in animals with diet-induced hypertriglyceridemia. In summary, ApoC3 is an important independent correlate of TG-rich lipoprotein concentrations in rhesus macaques consuming a high-fructose diet. ApoC3 is a promising therapeutic target for hypertriglyceridemia in patients with MetS and diabetes.


Assuntos
Apolipoproteína C-III/metabolismo , Óleos de Peixe/farmacologia , Hipertrigliceridemia/tratamento farmacológico , Hipertrigliceridemia/metabolismo , Interferência de RNA , Animais , Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Frutose , Hipertrigliceridemia/induzido quimicamente , Macaca mulatta , Masculino
7.
Appl Environ Microbiol ; 84(23)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30266729

RESUMO

Several studies monitoring alterations in the community structure upon resistant starch (RS) interventions are available, although comprehensive function-based analyses are lacking. Recently, a multiomics approach based on 16S rRNA gene sequencing, metaproteomics, and metabolomics on fecal samples from individuals subjected to high and low doses of type 2 RS (RS2; 48 g and 3 g/2,500 kcal, respectively, daily for 2 weeks) in a crossover intervention experiment was performed. In the present study, we did pathway-based metagenomic analyses on samples from a subset of individuals (n = 12) from that study to obtain additional detailed insights into the functional structure at high resolution during RS2 intervention. A mechanistic framework based on obtained results is proposed where primary degradation was governed by Firmicutes, with Ruminococcus bromii as a major taxon involved, providing fermentation substrates and increased acetate concentrations for the growth of various major butyrate producers exhibiting the enzyme butyryl-coenzyme A (CoA):acetate CoA-transferase. H2-scavenging sulfite reducers and acetogens concurrently increased. Individual responses of gut microbiota were noted, where seven of the 12 participants displayed all features of the outlined pattern, whereas four individuals showed mixed behavior and one subject was unresponsive. Intervention order did not affect the outcome, emphasizing a constant substrate supply for maintaining specific functional communities.IMPORTANCE Manipulation of gut microbiota is increasingly recognized as a promising approach to reduce various noncommunicable diseases, such as obesity and type 2 diabetes. Specific dietary supplements, including resistant starches (RS), are often a focus, yet comprehensive insights into functional responses of microbiota are largely lacking. Furthermore, unresponsiveness in certain individuals is poorly understood. Our data indicate that distinct parts of microbiota work jointly to degrade RS and successively form health-promoting fermentation end products. It highlights the need to consider both primary degraders and specific more-downstream-acting bacterial groups in order to achieve desired intervention outcomes. The gained insights will assist the design of personalized treatment strategies based on an individual's microbiota.


Assuntos
Bactérias/genética , Bactérias/isolamento & purificação , Diabetes Mellitus Tipo 2/microbiologia , Microbioma Gastrointestinal , Amido/metabolismo , Adolescente , Bactérias/classificação , Bactérias/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/metabolismo , Fezes/microbiologia , Feminino , Humanos , Masculino , Metagenômica , Filogenia , Amido/análise
8.
Sci Rep ; 7: 44845, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28332596

RESUMO

Recent findings have shown an inverse association between circulating C15:0/C17:0 fatty acids with disease risk, therefore, their origin needs to be determined to understanding their role in these pathologies. Through combinations of both animal and human intervention studies, we comprehensively investigated all possible contributions of these fatty acids from the gut-microbiota, the diet, and novel endogenous biosynthesis. Investigations included an intestinal germ-free study and a C15:0/C17:0 diet dose response study. Endogenous production was assessed through: a stearic acid infusion, phytol supplementation, and a Hacl1-/- mouse model. Two human dietary intervention studies were used to translate the results. Finally, a study comparing baseline C15:0/C17:0 with the prognosis of glucose intolerance. We found that circulating C15:0/C17:0 levels were not influenced by the gut-microbiota. The dose response study showed C15:0 had a linear response, however C17:0 was not directly correlated. The phytol supplementation only decreased C17:0. Stearic acid infusion only increased C17:0. Hacl1-/- only decreased C17:0. The glucose intolerance study showed only C17:0 correlated with prognosis. To summarise, circulating C15:0 and C17:0 are independently derived; C15:0 correlates directly with dietary intake, while C17:0 is substantially biosynthesized, therefore, they are not homologous in the aetiology of metabolic disease. Our findings emphasize the importance of the biosynthesis of C17:0 and recognizing its link with metabolic disease.


Assuntos
Açúcares da Dieta/metabolismo , Ácidos Graxos/metabolismo , Microbioma Gastrointestinal , Intolerância à Glucose , Animais , Vias Biossintéticas , Dieta , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/metabolismo , Açúcares da Dieta/administração & dosagem , Suplementos Nutricionais , Teste de Tolerância a Glucose , Humanos , Camundongos , Ratos
9.
Am J Clin Nutr ; 102(6): 1339-46, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26561632

RESUMO

BACKGROUND: Adverse effects of industrially produced trans fatty acids (iTFAs) on the risk of coronary artery disease are well documented in the scientific literature; however, effects of naturally occurring trans fatty acids (TFAs) from ruminant animals (rTFA), such as vaccenic acid (VA) and cis-9,trans-11 conjugated linoleic acid (c9,t11-CLA), are less clear. Although animal and cell studies suggest that VA and c9,t11-CLA may be hypocholesterolemic and antiatherogenic, epidemiologic data comparing rTFAs and iTFAs are inconsistent, and human intervention studies have been limited, underpowered, and not well controlled. OBJECTIVE: We determined the effects of VA, c9,t11-CLA, and iTFA, in the context of highly controlled diets (24 d each), on lipoprotein risk factors compared with a control diet. RESULTS: We conducted a double-blind, randomized, crossover feeding trial in 106 healthy adults [mean ± SD age: 47 ± 10.8 y; body mass index (in kg/m(2)): 28.5 ± 4.0; low-density lipoprotein (LDL) cholesterol: 3.24 ± 0.63 mmol/L]. Diets were designed to have stearic acid replaced with the following TFA isomers (percentage of energy): 0.1% mixed isomers of TFA (control), ∼3% VA, ∼3% iTFA, or 1% c9,t11-CLA. Total dietary fat (34% of energy) and other macronutrients were matched. Total cholesterol (TC), LDL cholesterol, triacylglycerol, lipoprotein(a), and apolipoprotein B were higher after VA than after iTFA; high-density lipoprotein (HDL) cholesterol and apolipoprotein AI also were higher after VA. Compared with control, VA and iTFA both increased TC, LDL cholesterol, ratio of TC to HDL cholesterol, and apolipoprotein B (2-6% change; P < 0.05); VA also increased HDL cholesterol, apolipoprotein AI, apolipoprotein B, and lipoprotein(a) (2-6% change; P < 0.05), whereas iTFA did not. c9,t11-CLA lowered triacylglycerol (P ≤ 0.01) and had no effect on other lipoprotein risk factors. CONCLUSIONS: With respect to risk of cardiovascular disease, these results are consistent with current nutrition labeling guidelines, with the requirement of VA, but not c9,t11-CLA, to be listed under TFA on the Nutrition Facts Panel. This trial was registered at clinicaltrials.gov as NCT00942656.


Assuntos
LDL-Colesterol/agonistas , Gorduras Insaturadas na Dieta/efeitos adversos , Hipercolesterolemia/etiologia , Ácidos Linoleicos Conjugados/efeitos adversos , Ácidos Oleicos/efeitos adversos , Óleos de Plantas/efeitos adversos , Ácidos Graxos trans/efeitos adversos , Adulto , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Colesterol/agonistas , Colesterol/sangue , LDL-Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Hidrogenação , Hipercolesterolemia/sangue , Hipercolesterolemia/fisiopatologia , Hipertrigliceridemia/sangue , Hipertrigliceridemia/etiologia , Hipertrigliceridemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Óleos de Plantas/química , Fatores de Risco , Triglicerídeos/agonistas , Triglicerídeos/sangue
10.
Annu Rev Nutr ; 35: 517-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26185980

RESUMO

The effects of saturated fatty acids (SFAs) on cardiovascular disease (CVD) risk are modulated by the nutrients that replace them and their food matrices. Replacement of SFAs with polyunsaturated fatty acids has been associated with reduced CVD risk, although there is heterogeneity in both fatty acid categories. In contrast, replacement of SFAs with carbohydrates, particularly sugar, has been associated with no improvement or even a worsening of CVD risk, at least in part through effects on atherogenic dyslipidemia, a cluster of traits including small, dense low-density lipoprotein particles. The effects of dietary SFAs on insulin sensitivity, inflammation, vascular function, and thrombosis are less clear. There is growing evidence that SFAs in the context of dairy foods, particularly fermented dairy products, have neutral or inverse associations with CVD. Overall dietary patterns emphasizing vegetables, fish, nuts, and whole versus processed grains form the basis of heart-healthy eating and should supersede a focus on macronutrient composition.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos/administração & dosagem , Animais , Produtos Fermentados do Leite , Laticínios , Dieta , Carboidratos da Dieta/efeitos adversos , Gorduras na Dieta/efeitos adversos , Dislipidemias/etiologia , Grão Comestível , Peixes , Humanos , Nozes , Verduras
11.
Eur Heart J ; 36(17): 1012-22, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25694464

RESUMO

Statin-associated muscle symptoms (SAMS) are one of the principal reasons for statin non-adherence and/or discontinuation, contributing to adverse cardiovascular outcomes. This European Atherosclerosis Society (EAS) Consensus Panel overviews current understanding of the pathophysiology of statin-associated myopathy, and provides guidance for diagnosis and management of SAMS. Statin-associated myopathy, with significant elevation of serum creatine kinase (CK), is a rare but serious side effect of statins, affecting 1 per 1000 to 1 per 10 000 people on standard statin doses. Statin-associated muscle symptoms cover a broader range of clinical presentations, usually with normal or minimally elevated CK levels, with a prevalence of 7-29% in registries and observational studies. Preclinical studies show that statins decrease mitochondrial function, attenuate energy production, and alter muscle protein degradation, thereby providing a potential link between statins and muscle symptoms; controlled mechanistic and genetic studies in humans are necessary to further understanding. The Panel proposes to identify SAMS by symptoms typical of statin myalgia (i.e. muscle pain or aching) and their temporal association with discontinuation and response to repetitive statin re-challenge. In people with SAMS, the Panel recommends the use of a maximally tolerated statin dose combined with non-statin lipid-lowering therapies to attain recommended low-density lipoprotein cholesterol targets. The Panel recommends a structured work-up to identify individuals with clinically relevant SAMS generally to at least three different statins, so that they can be offered therapeutic regimens to satisfactorily address their cardiovascular risk. Further research into the underlying pathophysiological mechanisms may offer future therapeutic potential.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Doenças Musculares/induzido quimicamente , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Terapias Complementares , Consenso , Creatina Quinase/metabolismo , Dieta , Predisposição Genética para Doença/etiologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Hipolipemiantes/uso terapêutico , Mitocôndrias Musculares , Doenças Mitocondriais/complicações , Doenças Musculares/diagnóstico , Doenças Musculares/terapia , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/antagonistas & inibidores , Fatores de Risco , Serina Endopeptidases
12.
Nat Med ; 19(5): 576-85, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23563705

RESUMO

Intestinal microbiota metabolism of choline and phosphatidylcholine produces trimethylamine (TMA), which is further metabolized to a proatherogenic species, trimethylamine-N-oxide (TMAO). We demonstrate here that metabolism by intestinal microbiota of dietary L-carnitine, a trimethylamine abundant in red meat, also produces TMAO and accelerates atherosclerosis in mice. Omnivorous human subjects produced more TMAO than did vegans or vegetarians following ingestion of L-carnitine through a microbiota-dependent mechanism. The presence of specific bacterial taxa in human feces was associated with both plasma TMAO concentration and dietary status. Plasma L-carnitine levels in subjects undergoing cardiac evaluation (n = 2,595) predicted increased risks for both prevalent cardiovascular disease (CVD) and incident major adverse cardiac events (myocardial infarction, stroke or death), but only among subjects with concurrently high TMAO levels. Chronic dietary L-carnitine supplementation in mice altered cecal microbial composition, markedly enhanced synthesis of TMA and TMAO, and increased atherosclerosis, but this did not occur if intestinal microbiota was concurrently suppressed. In mice with an intact intestinal microbiota, dietary supplementation with TMAO or either carnitine or choline reduced in vivo reverse cholesterol transport. Intestinal microbiota may thus contribute to the well-established link between high levels of red meat consumption and CVD risk.


Assuntos
Aterosclerose/etiologia , Carnitina/metabolismo , Intestinos/microbiologia , Metagenoma , Animais , Aterosclerose/microbiologia , Aterosclerose/fisiopatologia , Carnitina/química , Colesterol/metabolismo , Colina/química , Desmosterol/metabolismo , Feminino , Humanos , Macrófagos/metabolismo , Espectrometria de Massas , Carne , Metilaminas/sangue , Metilaminas/metabolismo , Camundongos , Camundongos Knockout , RNA/metabolismo , Fatores de Tempo
13.
FASEB J ; 26(8): 3515-27, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22549511

RESUMO

Dietary intake modulates disease risk, but little is known how components within food mixtures affect pathophysiology. A low-calorie, high-fiber, fruit-based nutrient-dense bar of defined composition (e.g., vitamins and minerals, fruit polyphenolics, ß-glucan, docosahexaenoic acid) appropriate for deconstruction and mechanistic studies is described and evaluated in a pilot trial. The bar was developed in collaboration with the U.S. Department of Agriculture. Changes in cardiovascular disease and diabetes risk biomarkers were measured after 2 wk twice-daily consumption of the bar, and compared against baseline controls in 25 healthy adults. Plasma HDL-cholesterol (HDL-c) increased 6.2% (P=0.001), due primarily to a 28% increase in large HDL (HDL-L; P<0.0001). Total plasma homocysteine (Hcy) decreased 19% (P=0.017), and glutathione (GSH) increased 20% (P=0.011). The changes in HDL and Hcy are in the direction associated with decreased risk of cardiovascular disease and cognitive decline; increased GSH reflects improved antioxidant defense. Changes in biomarkers linked to insulin resistance and inflammation were not observed. A defined food-based supplement can, within 2 wk, positively impact metabolic biomarkers linked to disease risk. These results lay the groundwork for mechanistic/deconstruction experiments to identify critical bar components and putative synergistic combinations responsible for observed effects.


Assuntos
Fibras na Dieta/administração & dosagem , Suplementos Nutricionais , Frutas , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , Feminino , Glutationa/sangue , Homocisteína/sangue , Humanos , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Risco
14.
Atherosclerosis ; 220(2): 470-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22169113

RESUMO

OBJECTIVE: Determine the effects of treatment with a selective PPAR-δ agonist±statin on plasma lipoprotein subfractions in dyslipidemic individuals. METHODS: Ion mobility analysis was used to measure plasma concentrations of subfractions of the full spectrum of lipoprotein particles in 166 overweight or obese dyslipidemic individuals treated with the PPAR-δ agonist MBX-8025 (50 and 100 mg/d)±atorvastatin (20 mg/d) in an 8-week randomized parallel arm double blind placebo controlled trial. RESULTS: MBX-8025 at both doses resulted in reductions of small plus very small LDL particles and increased levels of large LDL, with a concomitant reduction in large VLDL, and an increase in LDL peak diameter. This translated to reversal of the small dense LDL phenotype (LDL pattern B) in ∼90% of the participants. Modest increases in HDL particles were confined to the smaller HDL fractions. Atorvastatin monotherapy resulted in reductions in particles across the VLDL-IDL-LDL spectrum, with a significantly smaller reduction in small and very small LDL vs. MBX-8025 100 mg/d (-24.5±5.3% vs. -47.8±4.9%), and, in combination with MBX-8025, a reversal of the increase in large LDL. CONCLUSION: PPAR-δ and statin therapies have complementary effects in improving lipoprotein subfractions associated with atherogenic dyslipidemia.


Assuntos
Acetatos/uso terapêutico , Aterosclerose/tratamento farmacológico , Dislipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Lipoproteínas/sangue , PPAR gama/agonistas , Triazóis/uso terapêutico , Análise de Variância , Aterosclerose/sangue , Aterosclerose/etiologia , Atorvastatina , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Método Duplo-Cego , Quimioterapia Combinada , Dislipidemias/sangue , Dislipidemias/complicações , Feminino , Ácidos Heptanoicos/uso terapêutico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Sobrepeso/complicações , PPAR gama/metabolismo , Tamanho da Partícula , Pirróis/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
15.
Am J Clin Nutr ; 93(4): 684-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21270379

RESUMO

Current dietary recommendations advise reducing the intake of saturated fatty acids (SFAs) to reduce coronary heart disease (CHD) risk, but recent findings question the role of SFAs. This expert panel reviewed the evidence and reached the following conclusions: the evidence from epidemiologic, clinical, and mechanistic studies is consistent in finding that the risk of CHD is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs). In populations who consume a Western diet, the replacement of 1% of energy from SFAs with PUFAs lowers LDL cholesterol and is likely to produce a reduction in CHD incidence of ≥2-3%. No clear benefit of substituting carbohydrates for SFAs has been shown, although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index. Insufficient evidence exists to judge the effect on CHD risk of replacing SFAs with MUFAs. No clear association between SFA intake relative to refined carbohydrates and the risk of insulin resistance and diabetes has been shown. The effect of diet on a single biomarker is insufficient evidence to assess CHD risk. The combination of multiple biomarkers and the use of clinical endpoints could help substantiate the effects on CHD. Furthermore, the effect of particular foods on CHD cannot be predicted solely by their content of total SFAs because individual SFAs may have different cardiovascular effects and major SFA food sources contain other constituents that could influence CHD risk. Research is needed to clarify the role of SFAs compared with specific forms of carbohydrates in CHD risk and to compare specific foods with appropriate alternatives.


Assuntos
Doença das Coronárias/prevenção & controle , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos/efeitos adversos , Colesterol/sangue , Doença das Coronárias/sangue , Doença das Coronárias/etiologia , Diabetes Mellitus , Carboidratos da Dieta/farmacologia , Humanos , Resistência à Insulina
16.
Am J Clin Nutr ; 91(3): 502-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20089734

RESUMO

A focus of dietary recommendations for cardiovascular disease (CVD) prevention and treatment has been a reduction in saturated fat intake, primarily as a means of lowering LDL-cholesterol concentrations. However, the evidence that supports a reduction in saturated fat intake must be evaluated in the context of replacement by other macronutrients. Clinical trials that replaced saturated fat with polyunsaturated fat have generally shown a reduction in CVD events, although several studies showed no effects. An independent association of saturated fat intake with CVD risk has not been consistently shown in prospective epidemiologic studies, although some have provided evidence of an increased risk in young individuals and in women. Replacement of saturated fat by polyunsaturated or monounsaturated fat lowers both LDL and HDL cholesterol. However, replacement with a higher carbohydrate intake, particularly refined carbohydrate, can exacerbate the atherogenic dyslipidemia associated with insulin resistance and obesity that includes increased triglycerides, small LDL particles, and reduced HDL cholesterol. In summary, although substitution of dietary polyunsaturated fat for saturated fat has been shown to lower CVD risk, there are few epidemiologic or clinical trial data to support a benefit of replacing saturated fat with carbohydrate. Furthermore, particularly given the differential effects of dietary saturated fats and carbohydrates on concentrations of larger and smaller LDL particles, respectively, dietary efforts to improve the increasing burden of CVD risk associated with atherogenic dyslipidemia should primarily emphasize the limitation of refined carbohydrate intakes and a reduction in excess adiposity.


Assuntos
Doenças Cardiovasculares/etiologia , Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Ácidos Graxos/administração & dosagem , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Gorduras na Dieta/efeitos adversos , Dislipidemias/prevenção & controle , Ácidos Graxos/efeitos adversos , Ácidos Graxos Insaturados/administração & dosagem , Promoção da Saúde , Humanos , Obesidade , Fatores de Risco
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