Mendelian randomization (MR) provides us the opportunity to investigate the causal paths of metabolites in type 2 diabetes and glucose homeostasis. We developed and tested an MR approach based on genetic risk scoring for plasma metabolite levels, utilizing a pathway-based sensitivity analysis to control for nonspecific effects. We focused on 124 circulating metabolites that correlate with fasting glucose in the Erasmus Rucphen Family (ERF) study (n = 2,564) and tested the possible causal effect of each metabolite with glucose and type 2 diabetes and vice versa. We detected 14 paths with potential causal effects by MR, following pathway-based sensitivity analysis. Our results suggest that elevated plasma triglycerides might be partially responsible for increased glucose levels and type 2 diabetes risk, which is consistent with previous reports. Additionally, elevated HDL components, i.e., small HDL triglycerides, might have a causal role of elevating glucose levels. In contrast, large (L) and extra large (XL) HDL lipid components, i.e., XL-HDL cholesterol, XL-HDL–free cholesterol, XL-HDL phospholipids, L-HDL cholesterol, and L-HDL–free cholesterol, as well as HDL cholesterol seem to be protective against increasing fasting glucose but not against type 2 diabetes. Finally, we demonstrate that genetic predisposition to type 2 diabetes associates with increased levels of alanine and decreased levels of phosphatidylcholine alkyl-acyl C42:5 and phosphatidylcholine alkyl-acyl C44:4. Our MR results provide novel insight into promising causal paths to and from glucose and type 2 diabetes and underline the value of additional information from high-resolution metabolomics over classic biochemistry.

Aim To analyse the long-term impact of altered metabolism on the level of mediators of inflammatory response in female patients with type 2 diabetes. Methods This study included 97 female patients with type 2 diabetes and 107 female, nondiabetic control subjects, who were recruited at the Clinical Centre University of Sarajevo and the General Hospital Tešanj. The effects of glycaemic control on markers of inflammatory response represented by C-reactive protein (CRP), fibrinogen, leukocytes, sedimentation rate, and cytokine IL-6 were tested. All subjects were free of evidence of infections, surgery, thyroid disease, polycystic ovarian syndrome, active liver and kidney damage. All biochemical analyses were performed according to standard International Federation of Clinical Chemistry (IFCC) protocols. Results A significant increase of fibrinogen (p<0.001), CRP (p=0.001), interleukin-6 (p=0.013), leukocytes (p<0.001) and sedimentation rate (p=0.008) in diabetic female population compared to control subjects was found. A significant correlation between CRP and haemoglobin A1c (p=0.035), interleukin-6 and glucose (p=0.032), IL-6 and body mass index (p=0.007) was found. Conclusion Our data suggest that inflammation plays an important role in the pathogenesis of diabetes in female diabetic population. A more detailed study on a far larger number of subjects is needed if they were to be used effectively as biomarkers in the primary prevention of type 2 diabetes in this population.

Objective: Tobacco cigarette smoking is one of the major leading causes of death throughout the world. Smoking has both acute and chronic effect on haematological parameters. The aim of the present study was to assess the extent of adverse effects of cigarette smoking on biochemical characteristics in healthy smokers. Subjects and Method: One hundred and fifty six subjects participated in this study, 56 smokers and 100 non-smokers. The smokers were regularly consuming 10-20 cigarettes per day for at least 3 years. Complete blood cell count was analyzed by CELL-DYN 3700 fully automatic haematological analyzer. Results: The smokers had significantly higher levels of white blood cell (p<0,001), hemoglobin (p=0,042), mean corpuscular volume (p=0,001) and mean corpuscular hemoglobin concentration (p<0,001). All other measured parameters did not differ significantly. Cigarette smoking caused a significant increase (p<0,001) in red blood cells, white blood cells (p=0,040), hemoglobin (p<0,001), hematocrit (p=0,047) and mean corpuscular hemoglobin (p<0,001) in males in comparison to female smokers. Conclusion: In conclusion, our study showed that continuous cigarette smoking has severe adverse effects on haematological parameters (e.g., hemoglobin, white blood cells count, mean corpuscular volume, mean corpuscular hemoglobin concentration, red blood cells count, hematocrit) and these alterations might be associated with a greater risk for developing atherosclerosis, polycythemia vera, chronic obstructive pulmonary disease and/or cardiovascular diseases.

Therapeutic response to metformin, a first‐line drug for type 2 diabetes (T2D), is highly variable, in part likely due to genetic factors. To date, metformin pharmacogenetic studies have mainly focused on the impact of variants in metformin transporter genes, with inconsistent results. To clarify the significance of these variants in glycemic response to metformin in T2D, we performed a large‐scale meta‐analysis across the cohorts of the Metformin Genetics Consortium (MetGen). Nine candidate polymorphisms in five transporter genes (organic cation transporter [OCT]1, OCT2, multidrug and toxin extrusion transporter [MATE]1, MATE2‐K, and OCTN1) were analyzed in up to 7,968 individuals. None of the variants showed a significant effect on metformin response in the primary analysis, or in the exploratory secondary analyses, when patients were stratified according to possible confounding genotypes or prescribed a daily dose of metformin. Our results suggest that candidate transporter gene variants have little contribution to variability in glycemic response to metformin in T2D.

Our aim was to determine the incidence of prediabetes and risk of developing cardiovascular disease (CVD) in women with polycystic ovary syndrome (PCOS). This prospective, observational study included 148 women with PCOS, without Type 2 diabetes mellitus (T2DM) and CVD present at baseline. In the fasting blood samples, we measured lipids, glucose, and insulin levels during oral glucose tolerance test, levels of C-reactive protein (CRP), steroids, 25-hydroxyvitamin D (25-OHD), prolactin, thyroid-stimulating hormone, and parathyroid hormone. The follow-up period was 3 years. At baseline, prevalent prediabetes was present in 18 (12%) of PCOS cases and it progressed to T2DM in 5 (3%) of the cases. Incident prediabetes during the follow-up was noted in 47 (32%) women or 4.7 per 1000 persons/year. Prediabetes was associated with elevated body mass index (BMI) (odds ratio [OR] = 1.089, confidence interval [CI]: 1.010; 1.174, p = 0.026), high baseline levels of CRP (OR = 3.286, CI: 1.299; 8.312, p = 0.012), homeostatic model assessment - insulin resistance (IR) (OR = 2.628, CI: 1.535; 4.498, p < 0.001), and high lipid accumulation product (LAP) (OR = 1.009, CI: 1.003; 1.016, p = 0.005). Furthermore, prediabetes was associated with low 25-OHD (OR = 0.795, CI: 0.724; 0.880, p ≤ 0.05). In addition, cardiovascular risk in PCOS women with prediabetes was high (hazard ratio = 1.092, CI: 1.036; 1.128, p < 0.001). We showed association of prediabetes with high BMI, IR, markers of inflammation, LAP, and low serum 25-OHD concentration. IR appears to be more relevant than the other predictors of prediabetes risk in this study. PCOS women are considered as a high-risk population for prediabetes.

Introduction: Because of increasing prevalence of T2MD worldwide, it’s very important to recognize risk factors for diabetic complications, as soon as possible. Symptoms of complications appear a few or many years after tissue damage. So, it’s imperative to establish surveillance of diabetics with laboratory and other diagnostic procedures for early recognition of diabetic complications. Follow up of clinical curs of diabetes, by using databases of patients, provide possibility for permanent analysis of important laboratory parameters and any changes could be registered. Although an emerging evidence suggests a strong association of ALT (alanine aminotransferase) and γGT (gamma glutamyl transferase) activity with type 2 diabetes mellitus (T2DM), only a limited number of studies have analyzed the association of AST (aspartate aminotransferase), ALT, γGT, and ALP (alkaline phosphatase) activities in controlled T2DM. Material and Methods: Gender differences are of special interest in trying to follow diabetes progression and development of its complications. Here the activities of ALT, AST, γGT, ALP were analyzed as well as levels of glycosylated hemoglobin (HbA1c) and fasting plasma glucose (FPG) in 40 T2DM patients and 40 age-matched healthy subjects. Blood samples were collected from all participants in regular 3-months intervals up to 6 months period. Standard IFCC enzyme protocols were used to determine enzyme activities. Results and discussion: In first measured interval, significantly higher activities of ALT (p= 0,050) and glucose levels (p=0,045) were shown in male. A significant correlation was shown between ALT and AST activity with FPG and HbA1c levels in first and third measured interval. ALT activity was much higher in the group of patients with poor glycemia control. Average levels of activities of enzymes stay nearly in normal limits, but changes of enzymes activities should be recognized as soon as possible, earlier than tissue changes and diabetic complications become irreversible.

Aims Metformin is the most widely used oral anti-diabetes agent and has considerable benefits over other therapies, yet 20–30% of people develop gastrointestinal side effects, and 5% are unable to tolerate metformin due to the severity of these side effects. The mechanism for gastrointestinal side effects and their considerable inter-individual variability is unclear. We have recently shown the association between organic cation transporter 1 (OCT1) variants and severe intolerance to metformin in people with Type 2 diabetes. The aim of this study was to explore the association of OCT1 reduced-function polymorphisms with common metformin-induced gastrointestinal side effects in Type 2 diabetes. Methods This prospective observational cohort study included 92 patients with newly diagnosed Type 2 diabetes, incident users of metformin. Patients were genotyped for two common loss-of-function variants in the OCT1 gene (SLC22A1): R61C (rs12208357) and M420del (rs72552763). The association of OCT1 reduced-function alleles with gastrointestinal side effects was analysed using logistic regression. Results Forty-three patients (47%) experienced gastrointestinal adverse effects in the first 6 months of metformin treatment. Interestingly, the number of OCT1 reduced-function alleles was significantly associated with over two-fold higher odds of the common metformin-induced gastrointestinal side effects (odds ratio = 2.31, 95% confidence interval 1.07–5.01, P = 0.034). Conclusions In conclusion, we showed for the first time the association between OCT1 variants and common metformin-induced gastrointestinal side effects. These results confirm recent findings related to the role of OCT1 in severe metformin intolerance, and suggest that high inter-individual variability in mild/moderate and severe gastrointestinal intolerance share a common underlying mechanism. These data could contribute to more personalized and safer metformin treatment. Diabet. Med. 33, 511–514 (2016)

67 68 Metformin is the first-line antidiabetic drug with over 100 million users worldwide, yet its 69 mechanism of action remains unclear. Here the Metformin Genetics (MetGen) Consortium 70 reports a three-stage genome wide association study (GWAS), consisting of 13,123 participants of 71 different ancestries. The C-allele of rs8192675 in the intron of SLC2A2, which encodes the 72 facilitated glucose transporter GLUT2, was associated with a 0.17% (p=6.6x10) greater 73 metformin induced HbA1c reduction in 10,577 participants of European ancestry. rs8192675 is the 74 top cis-eQTL for SLC2A2 in 1,226 human liver samples, suggesting a key role for hepatic GLUT2 in 75 regulation of metformin action. In obese individuals C-allele homozygotes at rs8192675 had a 0.33% 76 (3.6mmol/mol) greater absolute HbA1c reduction than T-allele homozygotes.This is about half the 77 effect seen with the addition of a DPP-4 inhibitor, and equates to a dose difference of 550mg of 78 metformin, suggesting rs8192675 as a potential biomarker for stratified medicine. 79