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1.
Nutrients ; 15(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38140305

RESUMO

Background: Prolonged metformin treatment decreases vitamin B12 (B12) levels, whereas low B12 is associated with dyslipidaemia. Some studies have reported that metformin has no effect on intrahepatic triglyceride (TG) levels. Although AMP-activated protein kinase (AMPK) activation via adiponectin lowers hepatic TG content, its role in B12 deficiency and metformin has not been explored. We investigated whether low B12 impairs the beneficial effect of metformin on hepatic lipid metabolism via the AMPK-adiponectin axis. Methods: HepG2 was cultured using custom-made B12-deficient Eagle's Minimal Essential Medium (EMEM) in different B12-medium concentrations, followed by a 24-h metformin/adiponectin treatment. Gene and protein expressions and total intracellular TG were measured, and radiochemical analysis of TG synthesis and seahorse mitochondria stress assay were undertaken. Results: With low B12, total intracellular TG and synthesized radiolabelled TG were increased. Regulators of lipogenesis, cholesterol and genes regulating fatty acids (FAs; TG; and cholesterol biosynthesis were increased. FA oxidation (FAO) and mitochondrial function were decreased, with decreased pAMPKα and pACC levels. Following metformin treatment in hepatocytes with low B12, the gene and protein expression of the above targets were not alleviated. However, in the presence of adiponectin, intrahepatic lipid levels with low B12 decreased via upregulated pAMPKα and pACC levels. Again, combined adiponectin and metformin treatment ameliorated the low B12 effect and resulted in increased pAMPKα and pACC, with a subsequent reduction in lipogenesis, increased FAO and mitochondrion function. Conclusions: Adiponectin co-administration with metformin induced a higher intrahepatic lipid-lowering effect. Overall, we emphasize the potential therapeutic implications for hepatic AMPK activation via adiponectin for a clinical condition associated with B12 deficiency and metformin treatment.


Assuntos
Doenças Metabólicas , Metformina , Hepatopatia Gordurosa não Alcoólica , Humanos , Metformina/farmacologia , Células Hep G2 , Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/metabolismo , Vitamina B 12/farmacologia , Vitamina B 12/metabolismo , Fígado/metabolismo , Metabolismo dos Lipídeos , Ácidos Graxos/metabolismo , Doenças Metabólicas/metabolismo , Colesterol/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo
2.
BMC Pregnancy Childbirth ; 23(1): 563, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537535

RESUMO

BACKGROUND: Continuous glucose monitoring (CGM) provides the most objective method of assessing glucose in daily life. Although there have been small, short-term physiologic studies of glucose metabolism in 'healthy' pregnant women a comprehensive, longitudinal description of changes in glucose over the course of pregnancy and how glucose dysregulation earlier in pregnancy relates to traditional third trimester screening for gestational diabetes, fetal growth and pregnancy outcomes is lacking. This study aims to characterise longitudinal changes in glycemia across gestation using CGM, in order to understand the evolution of dysglycemia and its relationship to fetal growth. METHOD/DESIGN: A multi-centre, prospective, observational, cohort study of 500 healthy pregnant women, recruited in the first trimester of pregnancy. Masked CGM will be performed for a 14-day period on five occasions across pregnancy at ~ 10-12, 18-20, 26-28, 34-36 weeks gestation and postnatally. Routinely collected anthropometric and sociodemographic information will be recorded at each visit including: weight, height, blood pressure, current medication. Age, parity, ethnicity, smoking will be recorded. Blood samples will be taken at each visit for HbA1c and a sample stored. Details on fetal growth from ultrasound scans and the OGTT results will be recorded. Maternal and neonatal outcomes will be collected. CGM glucose profiling is the exposure of interest, and will be performed using standard summary statistics, functional data analysis and glucotyping. The primary maternal outcome is clinical diagnosis of GDM. The primary neonatal outcome is large for gestational age (LGA) (> 90th centile defined by customised birthweight centile). The relationship of glucose to key secondary maternal and neonatal outcomes will be explored. DISCUSSION: This study will ascertain the relationship of maternal dysglycemia to fetal growth and outcomes. It will explore whether CGM glucose profiling can detect GDM before the OGTT; or indeed whether CGM glucose profiling may be more useful than the OGTT at detecting LGA and other perinatal outcomes. TRIAL REGISTRATION: ISRCTN 15,706,303 https://www.isrctn.com/ISRCTN15706303 Registration date: 13th March 2023.


Assuntos
Diabetes Gestacional , Glucose , Feminino , Humanos , Gravidez , Glicemia/análise , Automonitorização da Glicemia , Estudos de Coortes , Desenvolvimento Fetal , Estudos Observacionais como Assunto , Resultado da Gravidez , Estudos Prospectivos , Estudos Multicêntricos como Assunto
3.
Diabetes ; 71(4): 837-852, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35073578

RESUMO

Serum progesterone sulfates were evaluated in the etiology of gestational diabetes mellitus (GDM). Serum progesterone sulfates were measured using ultra-performance liquid chromatography-tandem mass spectrometry in four patient cohorts: 1) the Hyperglycemia and Adverse Pregnancy Outcomes study; 2) London-based women of mixed ancestry and 3) U.K.-based women of European ancestry with or without GDM; and 4) 11-13 weeks pregnant women with BMI ≤25 or BMI ≥35 kg/m2 with subsequent uncomplicated pregnancies or GDM. Glucose-stimulated insulin secretion (GSIS) was evaluated in response to progesterone sulfates in mouse islets and human islets. Calcium fluorescence was measured in HEK293 cells expressing transient receptor potential cation channel subfamily M member 3 (TRPM3). Computer modeling using Molecular Operating Environment generated three-dimensional structures of TRPM3. Epiallopregnanolone sulfate (PM5S) concentrations were reduced in GDM (P < 0.05), in women with higher fasting plasma glucose (P < 0.010), and in early pregnancy samples from women who subsequently developed GDM with BMI ≥35 kg/m2 (P < 0.05). In islets, 50 µmol/L PM5S increased GSIS by at least twofold (P < 0.001); isosakuranetin (TRPM3 inhibitor) abolished this effect. PM5S increased calcium influx in TRPM3-expressing HEK293 cells. Computer modeling and docking showed identical positioning of PM5S to the natural ligand in TRPM3. PM5S increases GSIS and is reduced in GDM serum. The activation of GSIS by PM5S is mediated by TRPM3 in both mouse and human islets.


Assuntos
Diabetes Gestacional , Canais de Cátion TRPM , Animais , Glicemia/metabolismo , Cálcio/metabolismo , Feminino , Células HEK293 , Humanos , Insulina/metabolismo , Secreção de Insulina , Camundongos , Gravidez , Progesterona , Sulfatos/metabolismo
4.
Diabetologia ; 64(10): 2170-2182, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34296321

RESUMO

AIMS/HYPOTHESIS: The prevalence of gestational diabetes mellitus (GDM) is increasing worldwide in all ethnic groups. Low vitamin B12 and low/high folate levels may contribute to GDM risk, but there is conflicting evidence. Our aim is to assess the relationships of early pregnancy vitamin B12 and folate levels with the risk of GDM status at 26-28 weeks of gestation. METHODS: This was a prospective, multi-centre, multi-ethnic cohort study (n = 4746) in the UK. Participants who were eligible to be selectively screened as per the National Institute for Health and Care Excellence (NICE) criteria were included in the study. RESULTS: GDM prevalence was 12.5% by NICE and 14.7% by International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. Folate deficiency (1.3%) was rare but B12 insufficiency (42.3% at <220 pmol/l) and folate excess (36.5%) were common in early pregnancy. Early pregnancy median B12 levels were lower, and folate levels higher, in women who were diagnosed with GDM at 26-28 weeks. B12 was negatively associated with fasting plasma glucose (1 SD: -0.06 mmol/l; 95% CI -0.04, -0.08; p < 0.0001) and 2 h plasma glucose levels (-0.07 mmol/l; 95% CI -0.02, -0.12; p = 0.004). Higher B12 was associated with 14.4% lower RR of IADPSG-GDM (0.856; 95% CI 0.786, 0.933; p = 0.0004) after adjusting for key confounders (age, parity, smoking status, ethnicity, family history, household income and folate status). Approximately half of this association was mediated through BMI. Folate was positively associated with 2 h plasma glucose levels (0.08 mmol/l; 95% CI 0.04, 0.13; p = 0.0005) but its relationship with fasting plasma glucose was U-shaped (quadratic ß: 0.011; p = 0.05). Higher folate was associated with 11% higher RR of IADPSG-GDM (adjusted RR 1.11; 95% CI 1.036, 1.182; p = 0.002) (age, parity, smoking status, ethnicity, family history, household income and B12 status). Although no interactions were observed for B12 and folate (as continuous variables) with glucose levels and GDM risk, a low B12-high folate combination was associated with higher blood glucose level and risk of IADPSG-GDM (adjusted RR 1.742; 95% CI 1.226, 2.437; p = 0.003). CONCLUSIONS/INTERPRETATION: B12 insufficiency and folate excess were common in early pregnancy. Low B12 and high folate levels in early pregnancy were associated with small but statistically significant changes in maternal blood glucose level and higher RR of GDM. Our findings warrant additional studies on the role of unmetabolised folic acid in glucose metabolism and investigating the effect of optimising early pregnancy or pre-conception B12 and folate levels on subsequent hyperglycaemia. TRIAL REGISTRATION: ClinicalTrials.gov NCT03008824.


Assuntos
Diabetes Gestacional/sangue , Ácido Fólico/sangue , Gravidez em Diabéticas/sangue , Gravidez/sangue , Vitamina B 12/sangue , Adolescente , Adulto , Glicemia/metabolismo , Diabetes Gestacional/epidemiologia , Feminino , Deficiência de Ácido Fólico/sangue , Idade Gestacional , Cardiopatias/sangue , Cardiopatias/epidemiologia , Humanos , Pessoa de Meia-Idade , Gravidez em Diabéticas/epidemiologia , Prevalência , Estudos Prospectivos , Reino Unido/epidemiologia , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/epidemiologia , Adulto Jovem
5.
Cell Physiol Biochem ; 55(3): 241-255, 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33961354

RESUMO

BACKGROUND/AIMS: Rise in global incidence of obesity impacts metabolic health. Evidence from human and animal models show association of vitamin B12 (B12) deficiency with elevated BMI and lipids. Human adipocytes demonstrated dysregulation of lipogenesis by low B12 via hypomethylation and altered microRNAs. It is known de novo hepatic lipogenesis plays a key role towards dyslipidaemia, however, whether low B12 affects hepatic metabolism of lipids is not explored. METHODS: HepG2 was cultured in B12-deficient EMEM medium and seeded in different B12 media: 500nM(control), 1000pM(1nM), 100pM and 25pM(low) B12. Lipid droplets were examined by Oil Red O (ORO) staining using microscopy and then quantified by elution assay. Gene expression were assessed with real-time quantitative polymerase chain reaction (qRT-PCR) and intracellular triglycerides were quantified using commercial kit (Abcam, UK) and radiochemical assay. Fatty acid composition was measured by gas chromatography and mitochondrial function by seahorse XF24 flux assay. RESULTS: HepG2 cells in low B12 had more lipid droplets that were intensely stained with ORO compared with control. The total intracellular triglyceride and incorporation of radio-labelled-fatty acid in triglyceride synthesis were increased. Expression of genes regulating fatty acid, triglyceride and cholesterol biosynthesis were upregulated. Absolute concentrations of total fatty acids, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), trans-fatty acids and individual even-chain and odd-chain fatty acids were significantly increased. Also, low B12 impaired fatty acid oxidation and mitochondrial functional integrity in HepG2 compared with control. CONCLUSION: Our data provide novel evidence that low B12 increases fatty acid synthesis and levels of individual fatty acids, and decreases fatty acid oxidation and mitochondrial respiration, thus resulting in dysregulation of lipid metabolism in HepG2. This highlights the potential significance of de novo lipogenesis and warrants possible epigenetic mechanisms of low B12.


Assuntos
Ácidos Graxos/metabolismo , Lipogênese/efeitos dos fármacos , Fígado/metabolismo , Vitamina B 12/farmacologia , Células Hep G2 , Humanos , Fígado/patologia , Oxirredução/efeitos dos fármacos
6.
Int J Mol Sci ; 22(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33803025

RESUMO

The liver mass constitutes hepatocytes expressing receptors for vitamin B12 (B12)-bound transporters in circulation. However, intrahepatic and circulating B12 interrelationship levels remain unclear. We assessed the intracellular B12 levels at various circulating B12 concentrations in human HepG2 cell-line and liver tissue levels of B12 in the C57BL/6 mouse model. In HepG2 cells treated with a range of B12 concentrations, the intracellular and circulatory B12 levels, transcript and protein levels of B12 receptor (CD320) and transporter (TCN2) were determined using immunoassays, qRT-PCR and Western blot, respectively. Similar assessments were done in plasma and liver tissue of C57BL/6 mice, previously fed a diet of either a high or low B12 (30.82 µg B12/kg and 7.49 µg B12/kg, respectively) for 8-10 weeks. The physiological B12 status (0.15-1 nM) resulted in increased levels of intracellular B12 in HepG2 cells compared to supraphysiological levels of B12 (>1 nM). Gene and protein expression of CD320 and TCN2 were also higher at physiological levels of B12. Progressively increasing extracellular B12 to supraphysiological levels led to relative decreased levels of intracellular B12, lower expression of gene and protein levels of CD320 and TCN2. Similar results were observed in liver tissue from mice fed on a low B12 diet verses high B12 diet. These findings suggest that unlike supraphysiological B12, physiological levels of B12 in the extracellular media or circulation accelerates active transport of B12, and expression of CD320 and TCN2, resulting in higher relative uptake of B12 in hepatocytes.


Assuntos
Antígenos CD/metabolismo , Hepatócitos/metabolismo , Espaço Intracelular/metabolismo , Fígado/metabolismo , Receptores de Superfície Celular/metabolismo , Transcobalaminas/metabolismo , Vitamina B 12/metabolismo , Animais , Antígenos CD/genética , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/genética , Transcobalaminas/genética
7.
Trials ; 19(1): 682, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30541621

RESUMO

BACKGROUND: A diagnosis of gestational diabetes (GDM) is associated with an over sevenfold increase in the risk of developing type 2 diabetes (T2D), while among parous women with T2D, up to 30% have a history of GDM. Lifestyle interventions have been shown to reduce the risk of incident T2D in adults with impaired glucose tolerance, including in women with a history of GDM. The aim of this study is to establish whether a group self-management education programme, supported by a mobile web application, can improve levels of physical activity at 12 months in women who have had GDM. METHODS: The study is a randomised controlled trial with follow-up at 6 and 12 months. Primary outcome is change in objectively measured average daily physical activity at 12 months. Secondary outcomes include lipid profile, blood pressure, glycated haemoglobin, obesity, smoking and alcohol status, self-reported physical activity, anxiety, depression and quality of life. Participants are recruited from maternity and diabetes departments in hospital trusts in two sites in the UK. Women aged > 18 years, with a diagnosis of GDM during any pregnancy in the previous 60 months are eligible. Participants need to have a good understanding of written and verbal English, be able to give informed consent and have access to a smart-phone. Women who are pregnant or have type 1 or type 2 diabetes are not eligible. In total, 290 participants will be recruited and randomly assigned, with stratification for age and ethnicity, to either the control group, receiving usual care, or the intervention group who are invited to participate in the Baby Steps programme. This comprises a group education programme and access to a mobile web application which provides an education component and interacts with a wrist-worn activity monitor providing automated messages, setting challenges and encouraging motivation. DISCUSSION: If effective, the Baby Steps programme could be translated into a primary care-based intervention that women with GDM are referred to in the postnatal period. This could help them make lifestyle changes that could reduce their future risk of T2D. TRIAL REGISTRATION: ISRCTN, ISRCTN17299860 . Registered on 5 April 2017.


Assuntos
Actigrafia/instrumentação , Telefone Celular , Diabetes Gestacional/diagnóstico , Exercício Físico , Monitores de Aptidão Física , Processos Grupais , Estilo de Vida Saudável , Aplicativos Móveis , Educação de Pacientes como Assunto/métodos , Diabetes Gestacional/etnologia , Inglaterra/epidemiologia , Feminino , Humanos , Estudos Multicêntricos como Assunto , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Autocuidado , Fatores de Tempo , Resultado do Tratamento
8.
PLoS Med ; 15(1): e1002488, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29337985

RESUMO

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with developing type 2 diabetes, but very few studies have examined its effect on developing cardiovascular disease. METHODS AND FINDINGS: We conducted a retrospective cohort study utilizing a large primary care database in the United Kingdom. From 1 February 1990 to 15 May 2016, 9,118 women diagnosed with GDM were identified and randomly matched with 37,281 control women by age and timing of pregnancy (up to 3 months). Adjusted incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were calculated for cardiovascular risk factors and cardiovascular disease. Women with GDM were more likely to develop type 2 diabetes (IRR = 21.96; 95% CI 18.31-26.34) and hypertension (IRR = 1.85; 95% CI 1.59-2.16) after adjusting for age, Townsend (deprivation) quintile, body mass index, and smoking. For ischemic heart disease (IHD), the IRR was 2.78 (95% CI 1.37-5.66), and for cerebrovascular disease 0.95 (95% CI 0.51-1.77; p-value = 0.87), after adjusting for the above covariates and lipid-lowering medication and hypertension at baseline. Follow-up screening for type 2 diabetes and cardiovascular risk factors was poor. Limitations include potential selective documentation of severe GDM for women in primary care, higher surveillance for outcomes in women diagnosed with GDM than control women, and a short median follow-up postpartum period, with a small number of outcomes for IHD and cerebrovascular disease. CONCLUSIONS: Women diagnosed with GDM were at very high risk of developing type 2 diabetes and had a significantly increased incidence of hypertension and IHD. Identifying this group of women in general practice and targeting cardiovascular risk factors could improve long-term outcomes.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Hipertensão/epidemiologia , Isquemia Miocárdica/epidemiologia , Adolescente , Adulto , Estudos de Coortes , Diabetes Mellitus Tipo 2/etiologia , Diabetes Gestacional/epidemiologia , Diabetes Gestacional/etiologia , Feminino , Humanos , Hipertensão/etiologia , Pessoa de Meia-Idade , Isquemia Miocárdica/etiologia , Gravidez , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologia , Adulto Jovem
9.
BMC Pregnancy Childbirth ; 17(1): 226, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28705184

RESUMO

BACKGROUND: Early diagnosis of gestational diabetes mellitus (GDM) is crucial to prevent short term delivery risks and long term effects such as cardiovascular and metabolic diseases in the mother and infant. Diagnosing GDM in Sub-Saharan Africa (SSA) however, remains sub-optimal due to associated logistical and cost barriers for resource-constrained populations. A cost-effective strategy to screen for GDM in such settings are therefore urgently required. We conducted this study to determine the prevalence of gestational diabetes mellitus (GDM) and assess utility of various GDM point of care (POC) screening strategies in a resource-constrained setting. METHODS: Eligible women aged ≥18 years, and between 24 and 32 weeks of a singleton pregnancy, prospectively underwent testing over two days. On day 1, a POC 1-h 50 g glucose challenge test (GCT) and a POC glycated hemoglobin (HbA1c) was assessed. On day 2, fasting blood glucose, 1-h and 2-h 75 g oral glucose tolerance test (OGTT) were determined using both venous and POC tests, along with a venous HbA1c. The International Association of Diabetes in Pregnancy Study Group (IADPSG) criteria was used to diagnose GDM. GDM prevalence was reported with 95% confidence interval (CI). Specificity, sensitivity, positive predictive value, and negative predictive value of the various POC testing strategies were determined using IADPSG testing as the standard reference. RESULTS: Six hundred-sixteen eligible women completed testing procedures. GDM was diagnosed in 18 women, a prevalence of 2.9% (95% CI, 1.57% - 4.23%). Compared to IADPSG testing, POC IADPSG had a sensitivity and specificity of 55.6% and 90.6% respectively while that of POC 1-h 50 g GCT (using a diagnostic cut-off of ≥7.2 mmol/L [129.6 mg/dL]) was 55.6% and 63.9%. All other POC tests assessed showed poor sensitivity. CONCLUSIONS: POC screening strategies though feasible, showed poor sensitivity for GDM detection in our resource-constrained population of low GDM prevalence. Studies to identify sensitive and specific POC GDM screening strategies using adverse pregnancy outcomes as end points are required. TRIALS REGISTRATION: Clinical trials.gov : NCT02978807 , Registered 29 November 2016.


Assuntos
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiologia , Programas de Rastreamento/estatística & dados numéricos , Sistemas Automatizados de Assistência Junto ao Leito/estatística & dados numéricos , Diagnóstico Pré-Natal/estatística & dados numéricos , Adulto , Glicemia/análise , Feminino , Teste de Tolerância a Glucose/estatística & dados numéricos , Hemoglobinas Glicadas/análise , Humanos , Quênia/epidemiologia , Programas de Rastreamento/métodos , Valor Preditivo dos Testes , Gravidez , Diagnóstico Pré-Natal/métodos , Prevalência , Estudos Prospectivos , Valores de Referência , Sensibilidade e Especificidade
10.
Nutrients ; 8(9)2016 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-27608037

RESUMO

BACKGROUND: This study aimed to examine the relationship between changes in systemic vitamin B12 concentrations with pro-inflammatory cytokines, anthropometric factors and biochemical markers of cardiometabolic risk in a Saudi population. METHODS: A total of 364 subjects (224 children, age: 12.99 ± 2.73 (mean ± SD) years; BMI: 20.07 ± 4.92 kg/m² and 140 adults, age: 41.87 ± 8.82 years; BMI: 31.65 ± 5.77 kg/m²) were studied. Fasting blood, anthropometric and biochemical data were collected. Serum cytokines were quantified using multiplex assay kits and B12 concentrations were measured using immunoassay analyzer. RESULTS: Vitamin B12 was negatively associated with TNF-α (r = -0.14, p < 0.05), insulin (r = -0.230, p < 0.01) and HOMA-IR (r = -0.252, p < 0.01) in all subjects. In children, vitamin B12 was negatively associated with serum resistin (r = -0.160, p < 0.01), insulin (r = -0.248, p < 0.01), HOMA-IR (r = -0.261, p < 0.01). In adults, vitamin B12 was negatively associated with TNF-α (r = -0.242, p < 0.01) while positively associated with resistin (r = 0.248, p < 0.01). Serum resistin was the most significant predictor for circulating vitamin B12 in all subjects (r² = -0.17, p < 0.05) and in children (r² = -0.167, p < 0.01) while HDL-cholesterol was the predictor of B12 in adults (r² = -0.78, p < 0.05). CONCLUSIONS: Serum vitamin B12 concentrations were associated with pro-inflammatory cytokines and biochemical markers of cardiometabolic risks in adults. Maintaining adequate vitamin B12 concentrations may lower inflammation-induced cardiometabolic risk in the Saudi adult population.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Síndrome Metabólica/sangue , Vitamina B 12/sangue , Adiponectina/sangue , Adolescente , Adulto , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Doenças Cardiovasculares/prevenção & controle , Criança , Estudos Transversais , Feminino , Humanos , Inflamação/sangue , Inflamação/prevenção & controle , Insulina/sangue , Leptina/sangue , Lipídeos/sangue , Masculino , Síndrome Metabólica/prevenção & controle , Pessoa de Meia-Idade , Resistina/sangue , Fatores de Risco , Arábia Saudita , Fator de Necrose Tumoral alfa/sangue , Vitamina B 12/administração & dosagem , Circunferência da Cintura
11.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1012-1013: 186-92, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26851522

RESUMO

Disturbance in one-carbon (1-C) cycle occurs due to nutritional deficiencies (vitamin B12/folate) or specific genetic polymorphisms. This leads to altered levels of key 1-C metabolites such as SAM (s-adenosyl methionine), SAH (s-adenosyl homocysteine), methionine, homocysteine and MMA (methyl malonic acid). These 1-C metabolites are determinants of cellular methylation potential and epigenetic modifications of DNA which impairs metabolic pathways in several pathological diseases and developmental programming. Though methods were able to measure these analytes only independently, none of the methods detect simultaneously. Therefore we developed a method to measure these five 1-C metabolites in a single run using liquid chromatography tandem mass spectrometry (LC-MS/MS). We used stable isotopes dilution LC-MS/MS to measure the 1-C metabolites in human plasma. Blood samples were collected from pregnant women (n=30) at early gestation in the ongoing, multicentre, prospective PRiDE study. Linearity exhibited across the calibration range for all the analytes with the limit of detection (LOD) of 1.005nmol/l for SAM, 0.081nmol/l for SAH, 0.002µmol/l for methionine, 0.046µmol/l for homocysteine and 3.920nmol/l for MMA. The average recovery for SAM was 108%, SAH-110%, methionine-97%, homocysteine-91% and MMA-102%. The inter-assay CV for SAM was 7.3, SAH-5.6%, methionine-3.5%, homocysteine-7.0% and MMA-4.0%. The intra-assay CV for SAM was 8.7%, SAH-4.7%, methionine-5.4%, homocysteine-8.1% and MMA-6.1%. Pregnant women at early gestation with low B12 levels had significantly higher homocysteine, MMA, lower levels of methionine, SAM and SAM:SAH ratio and higher triglycerides. We developed a simple and rapid method to simultaneously quantify 1-C metabolites such as SAM, SAH, methionine, homocysteine and MMA in plasma by stable isotope dilution LC-MS/MS which would be useful to elucidate the epigenetic mechanisms related in the gene-nutrient interactions.


Assuntos
Homocisteína/sangue , Homocisteína/metabolismo , Marcação por Isótopo/métodos , Metionina/sangue , Metionina/metabolismo , Espectrometria de Massas em Tandem/métodos , Feminino , Homocisteína/química , Humanos , Limite de Detecção , Modelos Lineares , Metionina/química , Gravidez , Reprodutibilidade dos Testes , Deficiência de Vitamina B 12
12.
BMJ Case Rep ; 20162016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26733430

RESUMO

A 17-year-old Indian man was diagnosed with Bloom's syndrome at the age of 3 years. This is the first reported case of Bloom's in an Indian from the UK and the third case report from the British Isles. Bloom's is typically characterised by short stature, photosensitivity, telangiectatic erythema, learning difficulties, immunodeficiency and malignancy. He was born below the 0.4th centile and failed to gain weight as an infant. He presented in clinic with short stature, prominent facial features and hyperpigmented skin patches, which are all defining characteristics of Bloom's syndrome. Other case reports have documented early neoplasms, photosensitivity and learning difficulties in these patients; however, our patient is different, and currently attends a mainstream college, demonstrating little difficulty in coping with the work. To date, he has not presented with any malignancy or characteristic malar rash.


Assuntos
Síndrome de Bloom/diagnóstico , Adolescente , Diagnóstico Diferencial , Nanismo/diagnóstico , Humanos , Índia/etnologia , Masculino , Reino Unido
15.
Clin Epigenetics ; 7: 14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25763114

RESUMO

BACKGROUND: The dietary supply of methyl donors such as folate, vitamin B12, betaine, methionine, and choline is essential for normal growth, development, and physiological functions through the life course. Both human and animal studies have shown that vitamin B12 deficiency is associated with altered lipid profile and play an important role in the prediction of metabolic risk, however, as of yet, no direct mechanism has been investigated to confirm this. RESULTS: Three independent clinical studies of women (i) non-pregnant at child-bearing age, (ii) in early pregnancy, and (iii) at delivery showed that low vitamin B12 status was associated with higher total cholesterol, LDL cholesterol, and cholesterol-to-HDL ratio. These results guided the investigation into the cellular mechanisms of induced cholesterol biosynthesis due to vitamin B12 deficiency, using human adipocytes as a model system. Adipocytes cultured in low or no vitamin B12 conditions had increased cholesterol and homocysteine levels compared to control. The induction of cholesterol biosynthesis was associated with reduced s-adenosylmethionine (AdoMet)-to-s-adenosylhomocysteine (AdoHcy) ratio, also known as methylation potential (MP). We therefore studied whether reduced MP could lead to hypomethylation of genes involved in the regulation of cholesterol biosynthesis. Genome-wide and targeted DNA methylation analysis identified that the promoter regions of SREBF1 and LDLR, two key regulators of cholesterol biosynthesis, were hypomethylated under vitamin B12-deficient conditions, and as a result, their expressions and cholesterol biosynthesis were also significantly increased. This finding was further confirmed by the addition of the methylation inhibitor, 5-aza-2'-deoxycytidine, which resulted in increased SREBF1 and LDLR expressions and cholesterol accumulation in vitamin B12-sufficient conditions. Finally, we observed that the expression of SREBF1, LDLR, and cholesterol biosynthesis genes were increased in adipose tissue of vitamin B12 deficient mothers compared to control group. CONCLUSIONS: Clinical data suggests that vitamin B12 deficiency is an important metabolic risk factor. Regulation of AdoMet-to-AdoHcy levels by vitamin B12 could be an important mechanism by which it can influence cholesterol biosynthesis pathway in human adipocytes.

16.
Obesity (Silver Spring) ; 21(11): 2322-30, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23408599

RESUMO

OBJECTIVE: Central obesity and sub-clinical inflammation increase metabolic risk, this study examined the intracellular inflammatory pathways in adipose tissue (AT) that contribute to this risk. DESIGN AND METHODS: This study therefore addressed the influence of NFκB and JNK activation in human abdominal subcutaneous (AbdSc) and omental (Om) AT, the effect of adiposity, T2DM status and the role of TNFα in vitro, using molecular biology techniques. RESULTS: Our data showed NFκB activity is increased in Om AT versus AbdSc AT (P<0.01), which was reversed with respect to depot specific activation of JNK (P<0.01). However, T2DM status appeared to preferentially activate NFκB (P<0.001) over JNK. Furthermore, in vitro studies showed recombinant human (rh) TNFα treated AbdSc adipocytes increased NFκB activity over time (2-48 h, P<0.05) whilst JNK activity reduced (2 h, 4 h, P<0.05); inhibitor studies supported a preferential role for NFκB as a modulator of TNFα secretion. CONCLUSIONS: These studies suggest distinct changes in NFκB and JNK activation, dependent upon AT depot, adiposity and T2DM status, with in vitro use of rh TNFα leading to activation of NFκB. Consequently NFκB appears to play a central role in inflammatory mediated metabolic disease over JNK, highlighting NFκB as a potential key target for therapeutic intervention.


Assuntos
Tecido Adiposo/metabolismo , Adiposidade/fisiologia , Diabetes Mellitus Tipo 2/genética , NF-kappa B/fisiologia , Paniculite/genética , Fator de Necrose Tumoral alfa/fisiologia , Tecido Adiposo/imunologia , Tecido Adiposo/patologia , Adulto , Idoso , Células Cultivadas , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Inflamação/genética , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/genética , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Paniculite/metabolismo , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
17.
Trials ; 13: 164, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22971356

RESUMO

BACKGROUND: World-wide healthcare systems are faced with an epidemic of type 2 diabetes. In the United Kingdom, clinical care is primarily provided by general practitioners (GPs) rather than hospital specialists. Intermediate care clinics for diabetes (ICCD) potentially provide a model for supporting GPs in their care of people with poorly controlled type 2 diabetes and in their management of cardiovascular risk factors. This study aims to (1) compare patients with type 2 diabetes registered with practices that have access to an ICCD service with those that have access only to usual hospital care; (2) assess the cost-effectiveness of the intervention; and (3) explore the views and experiences of patients, health professionals and other stakeholders. METHODS/DESIGN: This two-arm cluster randomized controlled trial (with integral economic evaluation and qualitative study) is set in general practices in three UK Primary Care Trusts. Practices are randomized to one of two groups with patients referred to either an ICCD (intervention) or to hospital care (control). Intervention group: GP practices in the intervention arm have the opportunity to refer patients to an ICCD - a multidisciplinary team led by a specialist nurse and a diabetologist. Patients are reviewed and managed in the ICCD for a short period with a goal of improving diabetes and cardiovascular risk factor control and are then referred back to practice. or CONTROL GROUP: Standard GP care, with referral to secondary care as required, but no access to ICCD. Participants are adults aged 18 years or older who have type 2 diabetes that is difficult for their GPs to control. The primary outcome is the proportion of participants reaching three risk factor targets: HbA1c (≤7.0%); blood pressure (<140/80); and cholesterol (<4 mmol/l), at the end of the 18-month intervention period. The main secondary outcomes are the proportion of participants reaching individual risk factor targets and the overall 10-year risks for coronary heart disease(CHD) and stroke assessed by the United Kingdom Prospective Diabetes Study (UKPDS) risk engine. Other secondary outcomes include body mass index and waist circumference, use of medication, reported smoking, emotional adjustment, patient satisfaction and views on continuity, costs and health related quality of life. We aimed to randomize 50 practices and recruit 2,555 patients. DISCUSSION: Forty-nine practices have been randomized, 1,997 patients have been recruited to the trial, and 20 patients have been recruited to the qualitative study. Results will be available late 2012. TRIAL REGISTRATION: [ClinicalTrials.gov: Identifier NCT00945204].


Assuntos
Serviços de Saúde Comunitária , Diabetes Mellitus Tipo 2/terapia , Instituições para Cuidados Intermediários , Projetos de Pesquisa , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Serviços de Saúde Comunitária/economia , Análise Custo-Benefício , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/economia , Diabetes Mellitus Tipo 2/epidemiologia , Medicina Geral , Custos de Cuidados de Saúde , Instituições para Cuidados Intermediários/economia , Equipe de Assistência ao Paciente , Atenção Primária à Saúde , Encaminhamento e Consulta , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Reino Unido/epidemiologia
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