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1.
Clin Nutr ESPEN ; 54: 277-287, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36963874

RESUMO

BACKGROUND: Single doses of exogenous ketone salts (KS) transiently increase circulating beta-hydroxybutyrate (BHB) (∼1 mM; 1-2 h) regardless of starting levels of ketosis; however, no studies have explored how sustained use of KS influences measures of ketonemia and glycemia. OBJECTIVES: To determine the response to a hypocaloric, well-formulated ketogenic diet (KD), with and without the inclusion of two daily racemic KS doses (6 g R-BHB + 6 g S-BHB per serving) on 1) daily fasting capillary R-BHB and glucose (R-BHB/GLUfast), 2) bi-weekly 13 h diurnal BHB and glucose (R-BHB/GLUdiur), 3) three-hours post-KS ingestion kinetics (R-BHBKS), and 4) bi-weekly fasting plasma enantiomer-specific BHB (R/S-BHBplasma). METHODS: Non-diabetic adults with overweight and obesity were randomized to receive a precisely measured hypocaloric KD (∼75 %en of maintenance) for six weeks, supplemented twice-daily with KS or placebo (PL). A non-randomized comparison group was provided an isonitrogenous/isoenergetic low-fat diet (LFD). All meals were provided to subjects. Capillary blood was collected daily to measure R-BHB/GLUfast and hourly for R-BHB/GLUdiur. Plasma was collected to measure R/S-BHBplasma, insulin, fasting glucose, and insulin resistance (HOMA-IR). Total AUC was calculated using the trapezoidal method. RESULTS: Mean R-BHBfast increased significantly during KD + PL (1.0 mM BHB), an effect enhanced 26% during KD + KS. GLUfast AUC was -6% lower during KD + KS versus LFD. Mean R-BHBdiur increased 40% in KD + KS versus KD + PL, whereas GLUdiur decreased 13% during both KDs versus LFD. R-BHBKS peaked (Δ: ∼1 mM) 1 h after the morning KS dose, but not following the afternoon dose. Both R/S-BHBplasma increased during KD independent of KS inclusion. R-BHBplasma was 50-times greater compared to S-BHBplasma, and the KS augmented S-BHBplasma 50% more than PL. Fasting insulin and HOMA-IR decreased after 14 days independent of diet. CONCLUSIONS: A hypocaloric KD was effective at reducing diurnal glucose compared to a LFD independent of weight loss, but twice-daily racemic KS ingestion during KD augmented ketonemia, both as R- and S-BHB, and decreased mean fasting glucose beyond a KD alone. The hypoglycemic effects of KD in combination with exogenous ketones merit further investigation.


Assuntos
Dieta Cetogênica , Cetose , Adulto , Humanos , Ácido 3-Hidroxibutírico , Sais , Corpos Cetônicos , Cetonas , Glucose , Insulina , Jejum
2.
Front Neurosci ; 16: 971144, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248655

RESUMO

Background: Ketogenic diets are a commonly used weight loss method, but little is known how variations in sodium content and ketones influence cognition and mood during the early keto-adaptation period. Objectives: To investigate the effects of an exogenous ketone salt (KS) as part of a hypocaloric KD on mood and cognitive outcomes in overweight and obese adults. A secondary objective was to evaluate changes in biochemical markers associated with inflammatory and cognitive responses. Materials and methods: Adults who were overweight or obese participated in a 6-week controlled-feeding intervention comparing hypocaloric diets (∼75% of energy expenditure). KD groups received twice daily ketone salt (KD + KS; n = 12) or a flavor-matched placebo, free of minerals (KD + PL; n = 13). A separate group of age and BMI matched adults were later assigned to an isoenergetic low-fat diet (LFD; n = 12) as comparison to KD. Mood was assessed by shortened Profile of Mood States and Visual Analog Mood Scale surveys. Cognitive function was determined by the Automated Neuropsychological Assessment Metrics mental test battery. Results: Both KD groups achieved nutritional ketosis. Fasting serum glucose decreased in both KD groups, whereas glucose was unaffected in the LFD. Insulin decreased at week 2 and remained lower in all groups. At week 2, depression scores in the KD + PL group were higher compared to KD + KS. Performance in the math processing and go/no-go cognitive tests were lower for KD + PL and LFD participants, respectively, compared to KD + KS. Serum leptin levels decreased for all groups throughout the study but were higher for KD + KS group at week 6. Serum TNF-α steadily increased for LFD participants, reaching significance at week 6. Conclusion: During a short-term hypocaloric diet, no indication of a consistent decline in mood or cognitive function were seen in participants following either KD, despite KD + PL being relatively low in sodium. WK2 scores of "anger" and "depression" were higher in the LFD and KD + PL groups, suggesting that KS may attenuate negative mood parameters during the early intervention stages.

3.
Physiol Genomics ; 53(5): 173-192, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33818129

RESUMO

Mice have provided critical mechanistic understandings of clinical traits underlying metabolic syndrome (MetSyn) and susceptibility to MetSyn in mice is known to vary among inbred strains. We investigated the diet- and strain-dependent effects on metabolic traits in the eight Collaborative Cross (CC) founder strains (A/J, C57BL/6J, 129S1/SvImJ, NOD/ShiLtJ, NZO/HILtJ, CAST/EiJ, PWK/PhJ, and WSB/EiJ). Liver transcriptomics analysis showed that both atherogenic diet and host genetics have profound effects on the liver transcriptome, which may be related to differences in metabolic traits observed between strains. We found strain differences in circulating trimethylamine N-oxide (TMAO) concentration and liver triglyceride content, both of which are traits associated with metabolic diseases. Using a network approach, we identified a module of transcripts associated with TMAO and liver triglyceride content, which was enriched in functional pathways. Interrogation of the module related to metabolic traits identified NADPH oxidase 4 (Nox4), a gene for a key enzyme in the production of reactive oxygen species, which showed a strong association with plasma TMAO and liver triglyceride. Interestingly, Nox4 was identified as the highest expressed in the C57BL/6J and NZO/HILtJ strains and the lowest expressed in the CAST/EiJ strain. Based on these results, we suggest that there may be genetic variation in the contribution of Nox4 to the regulation of plasma TMAO and liver triglyceride content. In summary, we show that liver transcriptomic analysis identified diet- or strain-specific pathways for metabolic traits in the Collaborative Cross (CC) founder strains.


Assuntos
Camundongos de Cruzamento Colaborativo/genética , Camundongos de Cruzamento Colaborativo/metabolismo , Dieta , Fígado/fisiologia , Animais , Dieta Aterogênica/efeitos adversos , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Patrimônio Genético , Fígado/metabolismo , Metilaminas/sangue , Camundongos Endogâmicos C57BL , NADPH Oxidase 4/genética , Triglicerídeos/metabolismo
4.
Front Nutr ; 8: 618520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869263

RESUMO

Background: Ketogenic diets (KDs) that elevate beta-hydroxybutyrate (BHB) promote weight and fat loss. Exogenous ketones, such as ketone salts (KS), also elevate BHB concentrations with the potential to protect against muscle loss during caloric restriction. Whether augmenting ketosis with KS impacts body composition responses to a well-formulated KD remains unknown. Purpose: To explore the effects of energy-matched, hypocaloric KD feeding (<50 g carbohydrates/day; 1.5 g/kg/day protein), with and without the inclusion of KS, on weight loss and body composition responses. Methods: Overweight and obese adults were provided a precisely defined hypocaloric KD (~75% of energy expenditure) for 6 weeks. In a double-blind manner, subjects were randomly assigned to receive ~24 g/day of a racemic BHB-salt (KD + KS; n = 12) or placebo (KD + PL; n = 13). A matched comparison group (n = 12) was separately assigned to an isoenergetic/isonitrogenous low-fat diet (LFD). Body composition parameters were assessed by dual x-ray absorptiometry and magnetic resonance imaging. Results: The KD induced nutritional ketosis (>1.0 mM capillary BHB) throughout the study (p < 0.001), with higher fasting concentrations observed in KD + KS than KD + PL for the first 2 weeks (p < 0.05). There were decreases in body mass, whole body fat and lean mass, mid-thigh muscle cross-sectional area, and both visceral and subcutaneous adipose tissues (p < 0.001), but no group differences between the two KDs or with the LFD. Urine nitrogen excretion was significantly higher in KD + PL than LFD (p < 0.01) and trended higher in KD + PL compared to KD + KS (p = 0.076), whereas the nitrogen excretion during KD + KS was similar to LFD (p > 0.05). Conclusion: Energy-matched hypocaloric ketogenic diets favorably affected body composition but were not further impacted by administration of an exogenous BHB-salt that augmented ketosis. The trend for less nitrogen loss with the BHB-salt, if manifested over a longer period of time, may contribute to preserved lean mass.

5.
J Diet Suppl ; 17(5): 625-650, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32677481

RESUMO

In recent years, the role of the endocannabinoid system (ECS) in various cardiovascular conditions has been a subject of great interest. The ECS is composed of cannabinoid receptors, their endogenous ligands, also known as endocannabinoids, and enzymes responsible for the synthesis and degradation of endocannabinoids. Several lines of evidence suggest that the ECS plays a complex role in cardiac and vascular systems; however, under normal physiological conditions the functions of the ECS are limited. Overactivation of components of the ECS has been associated with various cardiovascular conditions. Intriguingly, activation of the ECS may also reflect a cardioprotective compensatory mechanism. With this knowledge, a range of naturally occurring and synthetic cannabinoid receptor agonists and antagonists, as well as inhibitors of endocannabinoid metabolic enzymes have emerged as promising approaches for the treatment or management of cardiovascular health. This review will first focus on the known role of the ECS in regulating the cardiovascular system. Secondly, we discuss emerging data highlighting the therapeutic potential of naturally occurring non-psychoactive ECS modulators within the cardiovascular system, including phytocannabinoids, terpenes, and the endocannabinoid-like molecule palmitoylethanolamide.


Assuntos
Canabinoides/farmacologia , Cannabis/química , Doenças Cardiovasculares/tratamento farmacológico , Sistema Cardiovascular/efeitos dos fármacos , Fitoterapia/métodos , Amidas/farmacologia , Endocanabinoides/metabolismo , Etanolaminas/farmacologia , Humanos , Ácidos Palmíticos/farmacologia , Terpenos/farmacologia
6.
Sci Rep ; 10(1): 6545, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300219

RESUMO

The gut microbiota is a critical mediator of nutrition and disease risk. Like most complex traits, the microbiome is under genetic regulation and differs between inbred strains of mice. We tested the effect of fecal microbiota transplantation (FMT) on obesity, and plasma glucose. For this study, we collected microbiota from 2 inbred strains of mice which differ in adiposity and glucose tolerance, C57BL/6J and WSB/EiJ. C57BL/6J female mice (n = 18) were first treated with antibiotics for 4 weeks to ablate the microbiota. Following ablation, the mice were transplanted with microbiota from a C57BL/6J or a WSB/EiJ mouse and clinical traits and plasma metabolomic profiles were interrogated at 2- and 4-weeks post-transplantation. Unexpectedly, the mice receiving WSB/EiJ microbiota increased adiposity but decreased plasma glucose. Metabolomic and 16S microbiota profiling indicated broad metabolic changes occurred during and after FMT. Detailed analysis of these interactions demonstrated specific microbiota-host metabolite interactions which may alter disease susceptibility.


Assuntos
Biomarcadores/sangue , Composição Corporal , Microbioma Gastrointestinal , Metabolômica , Adiposidade , Animais , Antibacterianos/farmacologia , Biodiversidade , Glicemia/metabolismo , Composição Corporal/efeitos dos fármacos , Colesterol/sangue , Transplante de Microbiota Fecal , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Análise Multivariada , Fenótipo , Filogenia , Análise de Componente Principal
7.
Mol Nutr Food Res ; 62(6): e1700692, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29322620

RESUMO

SCOPE: Xanthohumol (XN), a prenylated flavonoid found in hops, exhibits anti-inflammatory and antioxidant properties. However, poor bioavailability may limit therapeutic applications. As food components are known to modulate polyphenol absorption, the objective is to determine whether a protein matrix could enhance the bioavailability of XN post oral consumption in humans. METHODS AND RESULTS: This is a randomized, double-blind, crossover study in healthy participants (n = 6) evaluating XN and its major metabolites (isoxanthohumol [IX], 6- and 8-prenylnaringenin [6-PN, 8-PN]) for 6 h following consumption of 12.4 mg of XN delivered via a spent hops-rice protein matrix preparation or a control spent hops preparation. Plasma XN and metabolites are measured by LC-MS/MS. Cmax , Tmax , and area-under-the-curve (AUC) values were determined. Circulating XN and metabolite response to each treatment was not bioequivalent. Plasma concentrations of XN and XN + metabolites (AUC) are greater with consumption of the spent hops-rice protein matrix preparation. CONCLUSION: Compared to a standard spent hops powder, a protein-rich spent hops matrix demonstrates enhanced plasma levels of XN and metabolites following acute oral intake.


Assuntos
Flavonoides/sangue , Humulus , Oryza/química , Proteínas de Vegetais Comestíveis/administração & dosagem , Propiofenonas/sangue , Administração Oral , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino
8.
Int J Cardiol ; 212: 174-83, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27038728

RESUMO

BACKGROUND: Epigenetic modifications of the genome, such as DNA methylation and histone modifications, have been reported to play a role in processes underlying cardiovascular disease (CVD), including atherosclerosis, inflammation, hypertension and diabetes. METHODS: Eleven databases were searched for studies investigating the association between epigenetic marks (either global, site-specific or genome-wide methylation of DNA and histone modifications) and CVD. RESULTS: Of the 3459 searched references, 31 studies met our inclusion criteria (26 cross-sectional studies and 5 prospective studies). Overall, 12,648 individuals were included, with total of 4037 CVD events. The global DNA methylation assessed at long-interspersed nuclear element (LINE-1) was inversely associated with CVD, independent of established cardiovascular risk factors. Conversely, a higher degree of global DNA methylation measured at Alu repeats or by the LUMA method was associated with the presence of CVD. The studies reported epigenetic regulation of 34 metabolic genes (involved in fetal growth, glucose and lipid metabolism, inflammation, atherosclerosis and oxidative stress) in blood cells to be related with CVD. Among them, 5 loci were validated and methylation at F2RL3 was reported in two large prospective studies to predict cardiovascular disease beyond the traditional risk factors. CONCLUSIONS: Current evidence supports an association between genomic DNA methylation and CVD. However, this review highlights important gaps in the existing evidences including lack of large-scale epigenetic investigations, needed to reliably identify genomic loci where DNA methylation is related to risk of CVD.


Assuntos
Doenças Cardiovasculares/genética , Metilação de DNA , Elementos Alu , Epigênese Genética , Feminino , Loci Gênicos , Predisposição Genética para Doença , Histonas/metabolismo , Humanos , Masculino
9.
Int J Endocrinol ; 2016: 9545239, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26989412

RESUMO

Postprandial dyslipidaemia may be a plausible mechanism by which polycystic ovary syndrome (PCOS) increases cardiovascular risk. We sought to investigate whether the postprandial glucose and insulin and lipid and lipoprotein responses, including that of apolipoprotein B-48 (apoB-48) containing chylomicrons, to a mixed meal are different in obese PCOS women when compared to obese control subjects and whether differences, if any, are related to obesity, insulin resistance (IR), hyperandrogenaemia, or PCOS status. 26 women with PCOS (age 30.4 ± 1.2 years (mean ± SEM), body mass index (BMI) 36.8 ± 1.5 kg/m(2)) and 26 non-PCOS subjects (age 34.1 ± 0.9 years, BMI 31.5 ± 1.0 kg/m(2)) were studied before and up to 8 hours following a standard mixed meal. AUC-triglyceride (AUC-TG) was higher and AUC-high-density lipoprotein (AUC-HDL) lower in PCOS women. These differences were not apparent when BMI was accounted for. Insulin sensitivity (S I), AUC-apoB-48, and AUC-apolipoprotein B (AUC-apoB) were found to be independent predictors of AUC-TG, accounting for 55% of the variance. Only AUC-insulin remained significantly elevated following adjustment for BMI. Obesity related IR explains postprandial hypertriglyceridaemia and hyperinsulinaemic responses. Management of obesity in premenopausal women with PCOS is likely to reduce their cardiovascular risk burden.

10.
Mamm Genome ; 25(11-12): 583-99, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25159725

RESUMO

Intestinal microbial community structure is driven by host genetics in addition to environmental factors such as diet. In comparison with environmental influences, the effect of host genetics on intestinal microbiota, and how host-driven differences alter host metabolism is unclear. Additionally, the interaction between host genetics and diet, and the impact on the intestinal microbiome and possible down-stream effect on host metabolism is not fully understood, but represents another aspects of inter-individual variation in disease risk. The objectives of this study were to investigate how diet and genetic background shape microbial communities, and how these diet- and genetic-driven microbial differences relate to cardiometabolic phenotypes. To determine these effects, we used the 8 progenitor strains of the collaborative cross/diversity outbred mapping panels (C57BL/6J, A/J, NOD/ShiLtJ, NZO/HILtJ, WSB/EiJ, CAST/EiJ, PWK/PhJ, and 129S1/SvImJ). 16s rRNA profiling of enteric microbial communities in addition to the assessment of phenotypes central to cardiometabolic health was conducted under baseline nutritional conditions and in response to diets varying in atherogenic nutrient (fat, cholesterol, cholic acid) composition. These studies revealed strain-driven differences in enteric microbial communities which were retained with dietary intervention. Diet-strain interactions were seen for a core group of cardiometabolic-related microbial taxa. In conclusion, these studies highlight diet and genetically regulated cardiometabolic-related microbial taxa. Furthermore, we demonstrate the progenitor model is useful for nutrigenomic-based studies and screens seeking to investigate the interaction between genetic background and the phenotypic and microbial response to diet.


Assuntos
Metabolismo dos Carboidratos , Microbiota , Animais , Aterosclerose/genética , Aterosclerose/microbiologia , Composição Corporal , Dieta Aterogênica , Feminino , Estudos de Associação Genética , Resistência à Insulina , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Fenótipo , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Especificidade da Espécie
11.
Am J Clin Nutr ; 100(3): 778-86, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24944063

RESUMO

BACKGROUND: It is important to understand whether eating eggs, which are a major source of dietary choline, results in increased exposure to trimethylamine-N-oxide (TMAO), which is purported to be a risk factor for developing heart disease. OBJECTIVE: We determined whether humans eating eggs generate TMAO and, if so, whether there is an associated increase in a marker for inflammation [ie, high-sensitivity C-reactive protein (hsCRP)] or increased oxidation of low-density lipoprotein (LDL). DESIGN: In a longitudinal, double-blind, randomized dietary intervention, 6 volunteers were fed breakfast doses of 0, 1, 2, 4, or 6 egg yolks. Diets were otherwise controlled on the day before and day of each egg dose with a standardized low-choline menu. Plasma TMAO at timed intervals (immediately before and 1, 2, 4, 8, and 24 h after each dose), 24-h urine TMAO, predose and 24-h postdose serum hsCRP, and plasma oxidized LDL were measured. Volunteers received all 5 doses with each dose separated by >2-wk washout periods. RESULTS: The consumption of eggs was associated with increased plasma and urine TMAO concentrations (P < 0.01), with ∼14% of the total choline in eggs having been converted to TMAO. There was considerable variation between individuals in the TMAO response. There was no difference in hsCRP or oxidized LDL concentrations after egg doses. CONCLUSIONS: The consumption of ≥2 eggs results in an increased formation of TMAO. Choline is an essential nutrient that is required for normal human liver and muscle functions and important for normal fetal development. Additional study is needed to both confirm the association between TMAO and atherosclerosis and identify factors, microbiota and genetic, that influence the generation of TMAO before policy and medical recommendations are made that suggest reduced dietary choline intake.


Assuntos
Colina/efeitos adversos , Ovos/efeitos adversos , Cardiopatias/etiologia , Metilaminas/sangue , Regulação para Cima , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Proteína C-Reativa/análise , Colina/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Gema de Ovo/efeitos adversos , Feminino , Cardiopatias/sangue , Cardiopatias/epidemiologia , Cardiopatias/urina , Humanos , Lipoproteínas LDL/sangue , Estudos Longitudinais , Masculino , Metilaminas/urina , Pessoa de Meia-Idade , North Carolina/epidemiologia , Projetos Piloto , Fatores de Risco
12.
Hum Hered ; 75(2-4): 116-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24081227

RESUMO

Obesity is a polygenic chronic condition, and dysregulation in multiple underlying energy balance processes drives the obese phenotype. Lifestyle changes can be difficult to sustain long term, and anti-obesity drugs can be an advantageous component of a successful weight loss plan. However, due to lack of efficacy or adverse safety profiles, there is currently a limited selection of anti-obesity drugs on the market. This, coupled with the notable interindividual variability in efficacy of approved treatments, represents a significant unmet medical need. In this review, we will highlight this variability in weight loss response to these existing anti-obesity compounds and discuss how underpinning genetic variation is associated with weight loss outcomes. Existing research in the field of pharmacogenomics and obesity drugs will be highlighted, as will possibilities for future focus. We will conclude by exploring examples of successful pharmacogenomics studies, and also by asking how pharmacogenomics can be built into the drug development pipeline for the benefit of patients and pharmaceutical companies alike.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/genética , Fármacos Antiobesidade/efeitos adversos , Descoberta de Drogas , Humanos , Farmacogenética , Resultado do Tratamento , Redução de Peso/efeitos dos fármacos
13.
Metabolism ; 62(8): 1070-3, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23578923

RESUMO

OBJECTIVE: Obesity is a result of chronic overconsumption of calories relative to the amount of energy expended. While fat free mass can account for ~80% of the variance in energy expenditure, there is still considerable variability in energy requirements between individuals that cannot be explained. We hypothesized that responsiveness to the recently discovered myokine, irisin, which has been touted to increase energy expenditure via activation of brown adipocytes in rodents and possibly humans, may explain some of the variability in energy expenditure. MATERIALS/METHODS: Post-menopausal women (n=17) spent 24-h in a whole room indirect calorimeter. During the study day, subjects remained sedentary and consumed meals tailored to their energy requirements. Plasma irisin, leptin and adiponectin were measured in samples taken from each subject. RESULTS: Our results suggest that in general, irisin levels do not correlate with 24-h energy expenditure, however, for a subpopulation irisin levels and energy expenditure are highly correlative. CONCLUSION: Irisin may help explain some of the observed variability in individual energy requirements that cannot be accounted for by fat free mass. Therefore, interventions designed to increase irisin action may prove to be promising avenues for the treatment of obesity.


Assuntos
Composição Corporal/fisiologia , Metabolismo Energético/fisiologia , Fibronectinas/metabolismo , Absorciometria de Fóton , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Idoso , Calorimetria Indireta , Feminino , Humanos , Imunoprecipitação , Leptina/metabolismo , Pessoa de Meia-Idade , Obesidade/metabolismo
14.
Am J Clin Nutr ; 93(3): 652-62, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21270384

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is characterized by an adverse metabolic profile. Although dietary changes are advocated, optimal nutritional management remains uncertain. Polyunsaturated fatty acids (PUFAs), particularly long-chain (LC) n-3 (omega-3) PUFAs, improve metabolic health, but their therapeutic potential in PCOS is unknown. OBJECTIVES: We aimed to determine the associations between plasma PUFAs and metabolic and hormonal aspects of PCOS to investigate the efficacy of LC n-3 PUFA supplementation and to support the findings with mechanistic cellular studies. DESIGN: We selected a cross-sectional PCOS cohort (n = 104) and conducted a principal component analysis on plasma fatty acid profiles. Effects of LC n-3 PUFA supplementation on fasting and postprandial metabolic and hormonal markers were determined in PCOS subjects (n = 22) by a randomized, crossover, placebo-controlled intervention. Direct effects of n-6 (omega-6) compared with n-3 PUFAs on steroidogenesis were investigated in primary bovine theca cells. RESULTS: Cross-sectional data showed that a greater plasma n-6 PUFA concentration and n-6:n-3 PUFA ratio were associated with higher circulating androgens and that plasma LC n-3 PUFA status was associated with a less atherogenic lipid profile. LC n-3 PUFA supplementation reduced plasma bioavailable testosterone concentrations (P < 0.05), with the greatest reductions in subjects who exhibited greater reductions in plasma n-6:n-3 PUFA ratios. The treatment of bovine theca cells with n-6 rather than with n-3 PUFAs up-regulated androstenedione secretion (P < 0.05). CONCLUSIONS: Cross-sectional data suggest that PUFAs modulated hormonal and lipid profiles and that supplementation with LC n-3 PUFAs improves androgenic profiles in PCOS. In bovine theca cells, arachidonic acid modulated androstenedione secretion, which suggests an indirect effect of n-3 PUFAs through the displacement of or increased competition with n-6 PUFAs. This trial was registered at clinicaltrials.gov as NCT01189669.


Assuntos
Androgênios/sangue , Suplementos Nutricionais , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-3/uso terapêutico , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/dietoterapia , Adulto , Androgênios/metabolismo , Animais , Biomarcadores/sangue , Bovinos , Células Cultivadas , Estudos de Coortes , Estudos Cross-Over , Estudos Transversais , Método Duplo-Cego , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Ácidos Graxos Ômega-6/metabolismo , Feminino , Humanos , Ovário/citologia , Ovário/metabolismo , Período Pós-Prandial , Análise de Componente Principal , Células Tecais/metabolismo , Adulto Jovem
15.
Proc Nutr Soc ; 69(4): 628-35, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20696094

RESUMO

Polycystic ovary syndrome (PCOS) is a common, chronic endocrine condition affecting young women of reproductive age. It is characterised by hyperandrogenaemia, and profound menstrual and ovulatory dysfunction with consequent sub-fertility. A clustering of metabolic aberrations is commonly associated with this condition and these include insulin resistance, disordered lipid metabolism and chronic low-grade inflammation. Overweight and obesity, as well as a degree of adipose tissue dysfunction, are present in a large proportion of women with PCOS, and where present, magnify the inherent hyperandrogenaemia characteristic of the condition, in addition to worsening the metabolic profile. Diet and lifestyle interventions are among the first-line treatments for PCOS, and weight reduction through energy restriction has been shown to exert positive influences on both metabolic and hormonal aspects of this condition. Alterations in carbohydrate amount and type have also been investigated, and more recently, dietary fatty acids, with a particular emphasis on PUFA, have been shown to have a positive impact within this population group. Although it is likely that diet is not the root cause of PCOS, it represents a modifiable variable with the potential to improve the health of women with this condition. Work to date has provided insights into the role of diet in PCOS; however, further work is required to determine the role of nutrients specifically within the context of PCOS, in order to develop more effective, evidence-based dietary guidelines for this condition.


Assuntos
Androgênios , Gorduras na Dieta/uso terapêutico , Ácidos Graxos Insaturados/uso terapêutico , Obesidade/complicações , Síndrome do Ovário Policístico/dietoterapia , Tecido Adiposo/fisiopatologia , Feminino , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/fisiopatologia , Redução de Peso/fisiologia
16.
Mol Endocrinol ; 24(8): 1529-42, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20610534

RESUMO

Wingless-type mouse mammary tumor virus integration site family (WNT)/beta-catenin (CTNNB1) pathway components are expressed in ovarian granulosa cells, direct female gonad development, and are regulated by the pituitary gonadotropins. However, the in vivo functions of CTNNB1 during preovulatory follicular development, ovulation, and luteinization remain unclear. Using a mouse model Ctnnb1((Ex3)fl/fl);Cyp19-Cre (Ctnnb1((Ex3)gc-/-)), expressing dominant stable CTNNB1 in granulosa cells of small antral and preovulatory follicles, we show that CTNNB1 facilitates FSH-induced follicular growth and decreases the follicle atresia (granulosa cell apoptosis). At the molecular level, WNT signaling and FSH synergistically promote the expression of genes required for cell proliferation and estrogen biosynthesis, but decrease FOXO1, which negatively regulates proliferation and steroidogenesis. Conversely, dominant stable CTNNB1 represses LH-induced oocyte maturation, ovulation, luteinization, and progesterone biosynthesis. Specifically, granulosa cells in the Ctnnb1((Ex3)gc)(-/-) mice showed compromised responses to the LH surge and decreased levels of the epidermal growth factor-like factors (Areg and Ereg) that in vivo and in vitro mediate LH action. One underlying mechanism by which CTNNB1 prevents LH responses is by reducing phosphorylation of cAMP-responsive element-binding protein, which is essential for the expression of Areg and Ereg. By contrast, depletion of Ctnnb1 using the Ctnnb1(fl/fl);Cyp19-Cre mice did not alter FSH regulation of preovulatory follicular development or female fertility but dramatically enhanced LH induction of genes in granulosa cells in culture. Thus, CTNNB1 can enhance FSH and LH actions in antral follicles but overactivation of CTNNB1 negatively effects LH-induced ovulation and luteinization, highlighting the cell context-dependent and developmental stage-specific interactions of WNT/CTNNB1 pathway and G protein-coupled gonadotropin receptors in female fertility.


Assuntos
Luteinização/genética , Hormônio Luteinizante/farmacologia , Folículo Ovariano/metabolismo , Ovulação/genética , beta Catenina/metabolismo , Animais , Western Blotting , Feminino , Imunofluorescência , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Luteinização/efeitos dos fármacos , Camundongos , Camundongos Knockout , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Ovulação/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta Catenina/genética
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