The Protective Effect of Transcription Factor 7-Like 2 Risk Allele rs7903146 against Elevated Fasting Plasma Triglyceride in Type 2 Diabetes: A Meta-Analysis

The effects of transcription factor 7-like 2 rs7903146 and paired box 4 rs2233580 variants associated with type 2 diabetes on the therapeutic efficacy of hypoglycemic agents

Aim

This study aims to investigate the effects of the TCF7L2 rs7903146 and PAX4 rs2233580 (R192H) variants associated with T2D on the therapeutic efficacies of various HAs in patients with T2D after follow-up for 3 years.

Methods

A total of 526 patients who were followed up at the Diabetic Clinic of Siriraj Hospital during 2016-2019 were enrolled. The variants TCF7L2 rs7903146 and PAX4 rs2233580 (R192H) were genotyped using the RNase H2 enzyme-based amplification (rhAmp) technique and the associations between genotypes and glycemic control after treatments with different combinations HA were evaluated using Generalized Estimating Equations (GEE) analysis.

Results

Patients who carried TCF7L2 rs7903146C/T + T/T genotypes when they were treated with biguanide alone had significantly lower fasting plasma glucose (FPG) than those of the patients who carried the C/C genotype (p = 0.01). Patients who carried the PAX4 rs2233580 G/G genotype when they were treated with sulfonylurea alone had significantly lower FPG than those of the patients who carried G/A + A/A genotypes (p = 0.04).

Conclusion

Genotypes of TCF7L2 rs7903146 and PAX4 rs2233580 (R192H) variants associated with T2D influence the therapeutic responses to biguanide and sulfonylurea. Different genotypes of these two variants might distinctively affect the therapeutic effects of HAs. This finding provides evidence of pharmacogenetics in the treatment of diabetes.

Prevalence and clinical correlates of impaired glucose tolerance in first-episode versus chronic patients with schizophrenia

AIM

Studies using oral glucose tolerance tests (OGTT) have shown that impaired glucose metabolism presents in the early stages of schizophrenia (SCZ). However, there is a lack of studies on changes in glucose metabolism with the stage of the disease. We first explored the features of glucose metabolic pattern at different phases of male SCZ.

METHODS

We recruited 83 male first episode drug-naïve patients with SCZ (FEDN-SCZ) and 64 male chronic patients with SCZ (CH-SCZ), as well as 14 male healthy controls. The Positive and Negative Syndrome Scale (PANSS) was used to assess the psychopathology of patients. OGTT, fasting plasma glucose and lipid profiles of all participants were examined.

RESULTS

While the impaired glucose tolerance (IGT) rate of male SCZ patients was higher than that of HC (P < .05), there was no difference in IGT prevalence between FEDN-SCZ and CH-SCZ. In male FEDN-SCZ, LDL (OR = 2.64, 95% CI = 1.11-6.29, P = .028) and PANSS total score (OR = 1.03, 95% CI = 1.00-1.06, P = .046) were positively correlated with IGT; in male CH-SCZ, BMI (OR = 1.7, 95% CI = 1.08-2.67, P = .023), PANSS total score (OR = 0.82, 95% CI = 0.70-0.96, P = .015) and positive symptoms (OR = 0.45, 95% CI = 0.20-0.99, P = .046) were significantly correlated with IGT.

CONCLUSIONS

Our findings reflect different glucose metabolism patterns in different stages of SCZ.

"GENYAL" Study to Childhood Obesity Prevention: Methodology and Preliminary Results

Objective

This article describes the methodology and summarizes some preliminary results of the GENYAL study aiming to design and validate a predictive model, considering both environmental and genetic factors, that identifies children who would benefit most from actions aimed at reducing the risk of obesity and its complications.

Design

The study is a cluster randomized clinical trial with 5-year follow-up. The initial evaluation was carried out in 2017. The schools were randomly split into intervention (nutritional education) and control schools. Anthropometric measurements, social and health as well as dietary and physical activity data of schoolchildren and their families are annually collected. A total of 26 single nucleotide polymorphisms (SNPs) were assessed. Machine Learning models are being designed to predict obesity phenotypes after the 5-year follow-up.

Settings

Six schools in Madrid.

Participants

A total of 221 schoolchildren (6-8 years old).

Results

Collected results show that the prevalence of excess weight was 19.0, 25.4, and 32.2% (according to World Health Organization, International Obesity Task Force and Orbegozo Foundation criteria, respectively). Associations between the nutritional state of children with mother BMI [β = 0.21 (0.13-0.3), p (adjusted) <0.001], geographical location of the school [OR = 2.74 (1.24-6.22), p (adjusted) = 0.06], dairy servings per day [OR = 0.48 (0.29-0.75), p (adjusted) = 0.05] and 8 SNPs [rs1260326, rs780094, rs10913469, rs328, rs7647305, rs3101336, rs2568958, rs925946; p (not adjusted) <0.05] were found.

Conclusions

These baseline data support the evidence that environmental and genetic factors play a role in the development of childhood obesity. After 5-year follow-up, the GENYAL study pretends to validate the predictive model as a new strategy to fight against obesity.

Clinical Trial Registration

This study has been registered in ClinicalTrials.gov with the identifier NCT03419520, https://clinicaltrials.gov/ct2/show/NCT03419520.

Sex-specific associations of TCF7L2 variants with fasting glucose, type 2 diabetes and coronary heart disease among Turkish adults

Objective:

TCF7L2 is a repressor and transactivator of genes, and its variants are strongly associated with diabetes. This study aimed to evaluate the sex-specific relationship between the most common TCF7L2 gene variants (-98368G>T, rs12255372 and -47833C>T, rs7903146) with diabetes and coronary heart disease in Turkish Adult Risk Factor (TARF) Study.

Methods:

Single nucleotide variants (SNVs) have been genotyped using the TaqMan allelic discrimination assays in 2,024 (51.3% in women, age: 55±11.8) Turkish adults participating in the TARF study. Statistical analyses were used to investigate the association of genotypes with clinical and biochemical measurements.

Results:

Among the TARF study participants, 11.7%, 24.3%, 14.1%, and 38.3% had diabetes, hypertension, coronary heart disease (CHD), and obesity, respectively. The frequencies of T allele for -47833C>T and -98368G>T in Turkish adults were determined to be 0.35 and 0.33, respectively. -47833C>T was significantly associated with higher fasting glucose concentrations in all participants, especially in men. Both SNVs were significantly associated with diabetes and CHD in all participants (p<0.05). When study population was stratified according to sex, -98368G>T was associated with diabetes in women (p=0.041) and -47833C>T was associated with diabetes and CHD in men (p=0.018 and p=0.032, respectively). Also, both SNVs and the diplotypes of common haplotype (H1) remained strongly associated with type 2 diabetes after risk factors were adjusted (p<0.05).

Conclusion:

T allele homozygosity of two SNVs as well as the diplotype H1-/H1- reflects risk of diabetes primarily in men. Enhanced CHD risk is determined by the presence of diplotype H1-/H1- among nondiabetic participants.

Effects of TCF7L2 rs7903146 variant on metformin response in patients with type 2 diabetes

The response to metformin, the most commonly used drug for the treatment of type 2 diabetes (T2D), is highly variable. The common variant rs7903146 C>T within the transcription factor 7-like 2 gene (TCF7L2) is the strongest genetic risk factor associated with T2D to date. In this study, we explored the effects of the TCF7L2 rs7903146 genotype on metformin response in T2D. The study included 86 newly diagnosed patients with T2D, incident users of metformin. Levels of fasting glucose, insulin, HbA1c, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and anthropometric parameters were measured prior to metformin therapy, and 6 and 12 months after the treatment. Genotyping of the TCF7L2 rs7903146 was performed by the Sequenom MassARRAY® iPLEX® platform. At baseline, the diabetes risk allele (T) showed an association with lower triglyceride levels (p = 0.037). After 12 months of metformin treatment, the T allele was associated with 25.9% lower fasting insulin levels (95% CI 10.9-38.3%, p = 0.002) and 29.1% lower HOMA-IR index (95% CI 10.1-44.1%, p = 0.005), after adjustment for baseline values. Moreover, the T allele was associated with 6.7% lower fasting glucose levels (95% CI 1.1-12.0%, p = 0.021), adjusted for baseline glucose and baseline HOMA-%B levels, after 6 months of metformin treatment. This effect was more pronounced in the TT carriers who had 16.8% lower fasting glucose levels (95% CI 7.0-25.6%, p = 0.002) compared to the patients with CC genotype. Our results suggest that the TCF7L2 rs7903146 variant affects markers of insulin resistance and glycemic response to metformin in newly diagnosed patients with T2D within the first year of metformin treatment.

Metabolomics Reveal Altered Postprandial Lipid Metabolism After a High-Carbohydrate Meal in Men at High Genetic Risk of Diabetes

BACKGROUND

The transcription factor 7-like 2 (TCF7L2) gene confers one of the strongest genetic predispositions to type 2 diabetes, but diabetes development can be modified by diet.

OBJECTIVE

The aim of our study was to evaluate postprandial metabolic alterations in healthy men with a high genetic risk of diabetes, after two meals with varying macronutrient content.

METHODS

The study was conducted in 21 homozygous nondiabetic men carrying the high-risk (HR, n = 8, age: 31.2 ± 6.3 y, body mass index (BMI, kg/m2) 28.5 ± 8.1) or low-risk (LR, n = 13, age: 35.2 ± 10.3 y, BMI: 28.1 ± 6.4) genotypes at the rs7901695 locus. During two meal challenge test visits subjects received standardized isocaloric (450 kcal) liquid meals: high-carbohydrate (HC, carbohydrates: 89% of energy) and normo-carbohydrate (NC, carbohydrates: 45% of energy). Fasting (0 min) and postprandial (30, 60, 120, 180 min) plasma samples were analyzed for metabolite profiles through untargeted metabolomics. Metabolic fingerprinting was performed on an ultra-high-performance liquid chromatography (UHPLC) system connected to an iFunnel quadrupole-time-of-flight (Q-TOF) mass spectrometer.

RESULTS

In HR-genotype men, after the intake of an HC-meal, we noted a significantly lower area under the curves (AUCs) of postprandial plasma concentrations of most of the phospholipids (-37% to -53%, variable importance in the projection (VIP) = 1.2-1.5), lysophospholipids (-29% to -86%, VIP = 1.1-2.6), sphingolipids (-32% to -47%, VIP = 1.1-1.3), as well as arachidonic (-36%, VIP = 1.4) and oleic (-63%, VIP = 1.3) acids, their metabolites: keto- and hydoxy-fatty acids (-38% to -78%, VIP = 1.3-2.5), leukotrienes (-65% to -83%, VIP = 1.4-2.2), uric acid (-59%, VIP = 1.5), and pyroglutamic acid (-65%, VIP = 1.8). The AUCs of postprandial sphingosine concentrations were higher (125-832%, VIP = 1.9-3.2) after the NC-meal, AUCs of acylcarnitines were lower (-21% to -61%, VIP = 1.1-2.4), and AUCs of fatty acid amides were higher (51-508%, VIP = 1.7-3.1) after the intake of both meals.

CONCLUSIONS

In nondiabetic men carrying the TCF7L2 HR genotype, subtle but detectable modifications in intermediate lipid metabolism are induced by an HC-meal. This trial was registered at www.clinicaltrials.gov as NCT03792685.

Homozygous carriers of the TCF7L2 rs7903146 T-allele show altered postprandial response in triglycerides and triglyceride-rich lipoproteins

The TCF7L2 rs7903146 T-allele shows the strongest association with type 2 diabetes (T2D) among common gene variants. The aim of this study was to assess circulating levels of metabolites following a meal test in individuals carrying the high risk rs790346 TT genotype (cases) and low-risk CC genotype (controls). Sixty-two men were recruited based on TCF7L2 genotype, 31 were TT carriers and 31 were age- and BMI-matched CC carriers. All participants consumed a test meal after 12 hours of fasting. Metabolites were measured using proton nuclear magnetic resonance (NMR) spectroscopy. Metabolomic profiling of TCF7L2 carriers were performed for 141 lipid estimates. TT carriers had lower fasting levels of L-VLDL-L (total lipids in large very low density lipoproteins, p = 0.045), L-VLDL-CE (cholesterol esters in large VLDL, p = 0.03), and L-VLDL-C (total cholesterol in large VLDL, p = 0.045) compared to CC carriers. Additionally, TT carriers had lower postprandial levels of total triglycerides (TG) (q = 0.03), VLDL-TG (q = 0.05, including medium, small and extra small, q = 0.048, q = 0.0009, q = 0.04, respectively), HDL-TG (triglycerides in high density lipoproteins q = 0.037) and S-HDL-TG (q = 0.00003). In conclusion, TT carriers show altered postprandial triglyceride response, mainly influencing VLDL and HDL subclasses suggesting a genotype-mediated effect on hepatic lipid regulation.

Arterial Calcification in Diabetes Mellitus: Preclinical Models and Translational Implications

Diabetes mellitus increasingly afflicts our aging and dysmetabolic population. Type 2 diabetes mellitus and the antecedent metabolic syndrome represent the vast majority of the disease burden-increasingly prevalent in children and older adults. However, type 1 diabetes mellitus is also advancing in preadolescent children. As such, a crushing wave of cardiometabolic disease burden now faces our society. Arteriosclerotic calcification is increased in metabolic syndrome, type 2 diabetes mellitus, and type 1 diabetes mellitus-impairing conduit vessel compliance and function, thereby increasing the risk for dementia, stroke, heart attack, limb ischemia, renal insufficiency, and lower extremity amputation. Preclinical models of these dysmetabolic settings have provided insights into the pathobiology of arterial calcification. Osteochondrogenic morphogens in the BMP-Wnt signaling relay and transcriptional regulatory programs driven by Msx and Runx gene families are entrained to innate immune responses-responses activated by the dysmetabolic state-to direct arterial matrix deposition and mineralization. Recent studies implicate the endothelial-mesenchymal transition in contributing to the phenotypic drift of mineralizing vascular progenitors. In this brief overview, we discuss preclinical disease models that provide mechanistic insights-and point to challenges and opportunities to translate these insights into new therapeutic strategies for our patients afflicted with diabetes mellitus and its arteriosclerotic complications.

Impaired glucose tolerance in first-episode drug-naïve patients with schizophrenia: relationships with clinical phenotypes and cognitive deficits

BACKGROUND

Schizophrenia patients have a higher prevalence of type 2 diabetes mellitus with impaired glucose tolerance (IGT) than normals. We examined the relationship between IGT and clinical phenotypes or cognitive deficits in first-episode, drug-naïve (FEDN) Han Chinese patients with schizophrenia.

METHOD

A total of 175 in-patients were compared with 31 healthy controls on anthropometric measures and fasting plasma levels of glucose, insulin and lipids. They were also compared using a 75 g oral glucose tolerance test and the homeostasis model assessment of insulin resistance (HOMA-IR). Neurocognitive functioning was assessed using the MATRICS Consensus Cognitive Battery (MCCB). Patient psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Of the patients, 24.5% had IGT compared with none of the controls, and they also had significantly higher levels of fasting blood glucose and 2-h glucose after an oral glucose load, and were more insulin resistant. Compared with those patients with normal glucose tolerance, the IGT patients were older, had a later age of onset, higher waist or hip circumference and body mass index, higher levels of low-density lipoprotein and triglycerides and higher insulin resistance. Furthermore, IGT patients had higher PANSS total and negative symptom subscale scores, but no greater cognitive impairment except on the emotional intelligence index of the MCCB.

CONCLUSIONS

IGT occurs with greater frequency in FEDN schizophrenia, and shows association with demographic and anthropometric parameters, as well as with clinical symptoms but minimally with cognitive impairment during the early course of the disorder.

Analysis of the interaction between transcription factor 7-like 2 genetic variants with nopal and wholegrain fibre intake: effects on anthropometric and metabolic characteristics in type 2 diabetes patients

The transcription factor 7-like 2 (TCF7L2) genetic variants have shown differential effect on low-fat and high-fat diet in obese subjects. Nopal is a Mexican variety of cactus that is a traditional food and has been used in the treatment of diabetes. Its hypoglycaemic effect may be because of its soluble fibre (mucopolysaccharide) content. This study analysed the effects of the rs7903146 and rs12255372 TCF7L2 variants on anthropometric, metabolic and hormonal parameters in type 2 diabetes mellitus patients who consumed fibre from either nopal tortilla or wholegrain bread for 8 weeks. We followed-up seventy-four patients who consumed an individualised isoenergetic diet that included nopal tortilla (Diet 1) and sixty-three patients with a diet that included wholegrain bread (Diet 2). Anthropometric, metabolic and hormonal measures were collected at baseline and final intervention. The size effect and carry-over effect were estimated. To assess the interaction of genotype and diets, we used a general linear model repeated-measures analysis. Minor allele frequency of rs7903146T was 0·27 and for rs12255372T it was 0·13. At 8 weeks after Diet 1 intake, weight, BMI, waist and hip circumference decreased (P=0·00015) in rs7903146CC and rs12255372GG genotypes. In particular, patients carrying of the rs7903146CC and consuming Diet 1 showed a reduction in waist circumference of more than 2·5 cm compared with Diet 2 (P<0·001). No significant interaction between rs7903146 or rs12255372 and diet was seen in this study. In conclusion, in the carriers of the rs7903146CC and rs12255372GG wild types, significant changes in all anthropometric measures were observed, and had better response to both diets.

Toxicological Evaluation of Low Molecular Weight Fucoidan in Vitro and in Vivo

For a long time, fucoidan has been well known for its pharmacological activities, and recently low molecular weight fucoidan (LMF) has been used in food supplements and pharmaceutical products. In the present study, LMF was extracted from Laminaria japonica by enzyme hydrolysis. The toxicity of LMF in mouse and rat models was determined by many methods, such as total arsenic content, bacterial reverse mutation assay, chromosome aberration assay, and in vivo micronucleus assay. The present findings showed that LMF at 5000 μg/mL exhibited no mutagenicity. It also produced no formatting disruption of red blood cells in vivo. At 2000 mg/kg BW/day there were no toxicological indications. LMF is expected to be used as a safe food supplement.