Methodology in molecular genetics and its applications to diabetology

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Effect of simple, targeted diet in pregnant women with metabolic risk factors on maternal and fetal outcomes (ESTEEM): study protocol for a pragmatic multicentre randomised trial

This work was supported by Bart’s Charity. The California Walnut Commission and Blue Diamond Growers donated with thanks the mixed nuts provided to the ESTEEM participants. The trial sponsor is Queen Mary University of London

Acceptability and adherence to a Mediterranean diet in the postnatal period to prevent type 2 diabetes in women with gestational diabetes in the UK: a protocol for a single-arm feasibility study (MERIT)

Introduction: Women with gestational diabetes are at increased risk of developing type 2 diabetes later in life. In at-risk general populations, Mediterranean-style diet helps prevent type 2 diabetes. But its effect on postnatal women with a history of gestational diabetes is not known. Prior to a full-scale trial on Mediterranean-style diet in the postnatal period to prevent type 2 diabetes, a feasibility study is required to assess the acceptability of the diet and evaluate the trial processes. Methods and analysis: MEditerranean diet for pReventIon of type 2 diabeTes is a single-arm feasibility study (65 women) with qualitative evaluation of women who have recently given birth and had gestational diabetes. The intervention is a Mediterranean-style diet supplemented with nuts and olive oil, with dietary advice and an action plan. A dedicated Health Coach will interact with participants through an interactive lifestyle App. Women will follow the intervention from 6 to 13 weeks post partum until 1 year post partum. The primary outcomes are rates of recruitment, follow-up, adherence and attrition. The secondary outcomes are maternal dysglycaemia, cost and quality of life outcomes, and acceptability of the intervention to participants, and to healthcare professionals delivering the intervention. Feasibility outcomes will be reported using descriptive statistics. Ethics and dissemination: Ethical approval was obtained through the South Central—Berkshire Research Ethics Committee (19/SC/0064). Study findings will be disseminated via publication in peer-reviewed journals, as well as via newsletters made available to participants and members of Katie’s Team (a women’s health patient and public advisory group). Trial registration number: ISRCTN40582975

Integrated Genetic and Epigenetic Analysis Identifies Haplotype-Specific Methylation in the FTO Type 2 Diabetes and Obesity Susceptibility Locus

Recent multi-dimensional approaches to the study of complex disease have revealed powerful insights into how genetic and epigenetic factors may underlie their aetiopathogenesis. We examined genotype-epigenotype interactions in the context of Type 2 Diabetes (T2D), focussing on known regions of genomic susceptibility. We assayed DNA methylation in 60 females, stratified according to disease susceptibility haplotype using previously identified association loci. CpG methylation was assessed using methylated DNA immunoprecipitation on a targeted array (MeDIP-chip) and absolute methylation values were estimated using a Bayesian algorithm (BATMAN). Absolute methylation levels were quantified across LD blocks, and we identified increased DNA methylation on the FTO obesity susceptibility haplotype, tagged by the rs8050136 risk allele A (p = 9.40×10−4, permutation p = 1.0×10−3). Further analysis across the 46 kb LD block using sliding windows localised the most significant difference to be within a 7.7 kb region (p = 1.13×10−7). Sequence level analysis, followed by pyrosequencing validation, revealed that the methylation difference was driven by the co-ordinated phase of CpG-creating SNPs across the risk haplotype. This 7.7 kb region of haplotype-specific methylation (HSM), encapsulates a Highly Conserved Non-Coding Element (HCNE) that has previously been validated as a long-range enhancer, supported by the histone H3K4me1 enhancer signature. This study demonstrates that integration of Genome-Wide Association (GWA) SNP and epigenomic DNA methylation data can identify potential novel genotype-epigenotype interactions within disease-associated loci, thus providing a novel route to aid unravelling common complex diseases

Lack of effect of lowering LDL cholesterol on cancer: meta-analysis of individual data from 175,000 people in 27 randomised trials of statin therapy

<p>Background: Statin therapy reduces the risk of occlusive vascular events, but uncertainty remains about potential effects on cancer. We sought to provide a detailed assessment of any effects on cancer of lowering LDL cholesterol (LDL-C) with a statin using individual patient records from 175,000 patients in 27 large-scale statin trials.</p> <p>Methods and Findings: Individual records of 134,537 participants in 22 randomised trials of statin versus control (median duration 4.8 years) and 39,612 participants in 5 trials of more intensive versus less intensive statin therapy (median duration 5.1 years) were obtained. Reducing LDL-C with a statin for about 5 years had no effect on newly diagnosed cancer or on death from such cancers in either the trials of statin versus control (cancer incidence: 3755 [1.4% per year [py]] versus 3738 [1.4% py], RR 1.00 [95% CI 0.96-1.05]; cancer mortality: 1365 [0.5% py] versus 1358 [0.5% py], RR 1.00 [95% CI 0.93–1.08]) or in the trials of more versus less statin (cancer incidence: 1466 [1.6% py] vs 1472 [1.6% py], RR 1.00 [95% CI 0.93–1.07]; cancer mortality: 447 [0.5% py] versus 481 [0.5% py], RR 0.93 [95% CI 0.82–1.06]). Moreover, there was no evidence of any effect of reducing LDL-C with statin therapy on cancer incidence or mortality at any of 23 individual categories of sites, with increasing years of treatment, for any individual statin, or in any given subgroup. In particular, among individuals with low baseline LDL-C (<2 mmol/L), there was no evidence that further LDL-C reduction (from about 1.7 to 1.3 mmol/L) increased cancer risk (381 [1.6% py] versus 408 [1.7% py]; RR 0.92 [99% CI 0.76–1.10]).</p> <p>Conclusions: In 27 randomised trials, a median of five years of statin therapy had no effect on the incidence of, or mortality from, any type of cancer (or the aggregate of all cancer).</p&gt

Clinical efficacy and safety of a light mask for prevention of dark adaptation in treating and preventing progression of early diabetic macular oedema at 24 months (CLEOPATRA): a multicentre, phase 3, randomised controlled trial

Background: We aimed to assess 24-month outcomes of wearing an organic light-emitting sleep mask as an intervention to treat and prevent progression of non-central diabetic macular oedema. Methods: CLEOPATRA was a phase 3, single-blind, parallel-group, randomised controlled trial undertaken at 15 ophthalmic centres in the UK. Adults with non-centre-involving diabetic macular oedema were randomly assigned (1:1) to wearing either a light mask during sleep (Noctura 400 Sleep Mask, PolyPhotonix Medical, Sedgefield, UK) or a sham (non-light) mask, for 24 months. Randomisation was by minimisation generated by a central web-based computer system. Outcome assessors were masked technicians and optometrists. The primary outcome was the change in maximum retinal thickness on optical coherence tomography (OCT) at 24 months, analysed using a linear mixed-effects model incorporating 4-monthly measurements and baseline adjustment. Analysis was done using the intention-to-treat principle in all randomised patients with OCT data. Safety was assessed in all patients. This trial is registered with Controlled-Trials.com, number ISRCTN85596558. Findings: Between April 10, 2014, and June 15, 2015, 308 patients were randomly assigned to wearing the light mask (n=155) or a sham mask (n=153). 277 patients (144 assigned the light mask and 133 the sham mask) contributed to the mixed-effects model over time, including 246 patients with OCT data at 24 months. The change in maximum retinal thickness at 24 months did not differ between treatment groups (mean change −9·2 μm [SE 2·5] for the light mask vs −12·9 μm [SE 2·9] for the sham mask; adjusted mean difference −0·65 μm, 95% CI −6·90 to 5·59; p=0·84). Median compliance with wearing the light mask at 24 months was 19·5% (IQR 1·9–51·6). No serious adverse events were related to either mask. The most frequent adverse events related to the assigned treatment were discomfort on the eyes (14 with the light mask vs seven with the sham mask), painful, sticky, or watery eyes (14 vs six), and sleep disturbance (seven vs one). Interpretation: The light mask as used in this study did not confer long-term therapeutic benefit on non-centre-involving diabetic macular oedema and the study does not support its use for this indication. Funding: The Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health Research partnership

An integrative epi-transcriptomic approach identifies the human cartilage chitinase 3-like protein 2 (CHI3L2) as a potential mediator of B12 deficiency in adipocytes

Vitamin B12 has multiple biochemical functions including in the one-carbon cycle generating a methyl group for DNA methylation, and metabolism of fatty acids and amino acids to generate energy via the citric acid cycle. The aim of our study was to use a combined epigenomic and transcriptomic approach to identify novel genes mediating the effect of B12 on adipogenesis. Human pre-adipocytes (CHUB-S7) were treated with a range of B12 (0–500 nM) concentrations from the day of cell seeding until harvesting in discovery and validation experiments prior to genome-wide methylation analysis using the Illumina HumanMethylation 450Beadchip. For transcriptomic analysis, RNA-seq libraries were run on the Illumina HiSeq 2500. To further investigate the expression of any genes on human adipogenesis, a second human preadipocyte strain was studied (SGBS) by real-time quantitative PCR (qRT-PCR). A combined epigenetic and transcriptomic approach in differentiated human pre-adipocyte cell line, CHUB-S7, identified that the Human cartilage chitinase 3-like protein 2 (CHI3L2) gene was hypo-methylated and had increased expression in low B12 conditions. Furthermore, there was an approximately 1000-fold increase in CHI3L2 expression in the early days of adipocyte differentiation, which paralleled an increase of lipid droplets in differentiated SGBS cells and an increased expression level of markers of mature adipocytes. In summary, we have identified a potential role of the human cartilage chitinase 3-like protein 2 (CHI3L2) in adipocyte function in the presence of low B12 levels

Baseline Serum 25-Hydroxy Vitamin D Is Predictive of Future Glycemic Status and Insulin Resistance : The Medical Research Council Ely Prospective Study 1990–2000

OBJECTIVE—Accumulating epidemiological evidence suggests that hypovitaminosis D may be associated with type 2 diabetes and related metabolic risks. However, prospective data using the biomarker serum 25-hydroxyvitamin D [25(OH)D] are limited and therefore examined in the present study

Effect of Vitamin D Supplementation on Markers of Vascular Function: A Systematic Review and Individual Participant Meta- Analysis

Background-—Low 25-hydroxyvitamin D levels are associated with an increased risk of cardiovascular events, but the effect of vitamin D supplementation on markers of vascular function associated with major adverse cardiovascular events is unclear. Methods and Results-—We conducted a systematic review and individual participant meta-analysis to examine the effect of vitamin D supplementation on flow-mediated dilatation of the brachial artery, pulse wave velocity, augmentation index, central blood pressure, microvascular function, and reactive hyperemia index. MEDLINE, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials, and http://www.ClinicalTrials.gov were searched until the end of 2016 without language restrictions. Placebo-controlled randomized trials of at least4 weeks duration were included. Individual participant data were sought from investigators on included trials. Trial-level metaanalysis was performed using random-effects models; individual participant meta-analyses used a 2-stage analytic strategy, examining effects in prespecified subgroups. 31trials (2751 participants) were included; 29 trials (2641participants) contributed data to trial-level meta-analysis, and24trials (2051 participants) contributed to individual-participant analyses. VitaminD3daily dose equivalents ranged from 900 to 5000 IU; duration was 4 weeks to12 months. Trial-level meta-analysis showed no significant effect of supplementation on macrovascularmeasures(flow-mediateddilatation,0.37%[95%confidenceinterval, 0.23to0.97]; carotid-femoralpulsewavevelocity, 0.00 m/s [95% confidence interval, 0.36 to 0.37]); similar results were obtained from individual participant data. Microvascular function showed a modest improvement in trial-level data only. No consistent benefit was observed in subgroup analyses or between different vitamin D analogues. Conclusions-—Vitamin D supplementation had no significant effect on most markers of vascular function in this analysis