Decreased 25-Hydroxy Vitamin D Level Is Associated with All-Cause Mortality in Patients with Type 2 Diabetes at High Cardiovascular Risk.

Cardiovascular diseases are among the leading causes of morbidity and mortality, particularly in individuals with type 2 diabetes. There is a need for new biomarkers to improve the prediction of cardiovascular events and overall mortality. We investigated the association of selected atherosclerosis related biomarkers, specifically osteoprotegerin (OPG), 25-hydroxy-vitamin D (25(OH)D), C-reactive protein (CRP), lipopolysaccharide-binding protein (LBP), and asymmetric dimethylarginine (ADMA), with the occurrence of any cardiovascular event or all-cause mortality (primary outcome) during a 5.6-year follow-up of 190 patients with type 2 diabetes. Data were analyzed using logistic regression to adjust for baseline cardiovascular status and cardiovascular risk factors. The primary outcome occurred in 89 participants (46.8%) during the study. When analyzed individually, 25(OH)D, CRP, and LBP significantly predicted the primary outcome in multivariable models. However, in a model that included all biomarkers, only a decreased level of 25(OH)D remained a significant predictor of the primary outcome. Moreover, the level of 25(OH)D significantly predicted all-cause mortality: a reduction of 10 ng/mL was associated with a two-fold increase in all-cause mortality. Our study thus demonstrates that vitamin D deficiency was the strongest factor associated with the primary outcome and all-cause mortality after a 5.6-year follow-up in patients with type 2 diabetes at high cardiovascular risk.

Glycated haemoglobin as a marker of elevated LDL and TAG: a cohort study.

Patients with less severe glycated haemoglobin (HbA1c) targets may find it difficult to achieve the target values of lipid parameters treatment at high cardiovascular risk. We have been monitoring the correlation between levels of triglycerides (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) with glycosylated haemoglobin (HbA1c) by IFCC method (method of testing according to the International Federation of Clinical Chemistry and Laboratory Medicine) and by DCCT method (Diabetes Control and Complication Trial) as well as body mass index (BMI) at the time of diagnosis of the disease, that could help identify patients with an increased risk of cardiovascular disease. In the cohort study we were monitoring outpatients with newly diagnosed type 2 diabetes mellitus during a 5 year period. Patients (117 men, 83 women), aged from 30 to 92 years were conducted sampling blood glucose, HbA1c (IFCC/DCCT), HDL, LDL, TG. At baseline, the patients height, weight, waist circumference, calculated BMI and blood pressure were measured. Waist circumference was measured in the horizontal plane in the middle of the distance between the upper edge of the iliac crest and the lower edge of the last rib in the breath. Our study did not exclude patients taking statin or fibrate. The high HbA1c values increased the risk of elevating LDL-cholesterol levels and TAG levels in the whole group (p = 0.012) and (p = 0.017), and the high BMI values increased the risk of lowering HDL-cholesterol levels in the female population (p = 0.010). The results of our study stratify the increased risk of atherogenicity in these groups. HbA1c is a direct marker of elevated LDL and TAG, and indirect marker for coronary artery disease risk assessment.

Genetic variants associated with glycemic response to treatment with dipeptidylpeptidase 4 inhibitors.

Aim: We examined associations of eight SNPs in/near seven candidate genes with glycemic response to 6 month treatment with DPP4 inhibitors. Patients & methods: 206 patients with type 2 diabetes (116 men and 90 women) were treated with sitagliptin or vildagliptin (both 100 mg/day) in combination with metformin or metformin/sulphonylurea over 6 months, and the reduction in glycated hemoglobin (HbA1c) was measured. Results: Rs6923761 in GLP1R was significantly associated with a reduction in HbA1c (adjusted p = 0.006). Homozygotes for the minor A allele had smaller reduction in HbA1c by 0.4% (4 mmol/mol) than the G allele carriers (p = 0.016). Conclusion: The missense variant rs6923761 in the GLP1R gene was associated with a smaller glycemic response to 6 month gliptin therapy in diabetic patients of central European origin.

Risk allele of gene variant rs6584389 is associated with increased intima-media thickness in patients with type 2 diabetes.

BACKGROUND: Genome-wide association studies identified several gene variants associated with peripheral arterial disease (PAD). Among them, rs6584389 A>C was significantly associated with PAD defined by decreased ankle-brachial index (ABI). The aim of this study was to investigate whether the rs6584389 variant is also associated with the earlier stages of atherosclerosis assessed by intima-media thickness (IMT) or pulse-wave velocity (PWV) in clinically asymptomatic subjects with type 2 diabetes (T2DM), a group of patients with a high cardiovascular risk. PATIENTS AND METHODS: In total, 111 patients with T2DM (56 females, 55 males) with a mean age 63.0 ± 9.1 years were consecutively included in the study. IMT was measured by ultrasound using 7 MHz linear transducer. PWV was measured using a piezoelectric method. Genotyping for rs6584389 was performed by PCR-HRMA method. RESULTS: The carriers of the risk C-allele of rs6584389 variant had significantly higher mean left-side IMT (AA: 0.67 ± 0.12, AC 0.77 ± 0.21, CC 0.78 ± 0.22 mm; p = 0.04). In multiple linear regression analysis, rs6586389 genotype was significantly associated with all measured IMT parameters. The presence of each risk C-allele predicted an increase in left-side IMT by 0.056 mm (p = 0.017), right-side IMT by 0.053 mm (p = 0.039), average IMT by 0.054 mm (p = 0.023), and maximal IMT by 0.058 mm (p = 0.021). Age and HbA1c levels were also significantly associated with increased IMT in all multivariate models. CONCLUSIONS: Gene variant rs6584389 A>C near to PAX2 gene was associated with increased carotid IMT in patients with type 2 diabetes independently of the other main risk factors for atherosclerosis.

Osteoprotegerin concentration is associated with the presence and severity of peripheral arterial disease in type 2 diabetes mellitus.

BACKGROUND: Osteoprotegerin plays a role in the development of several bone diseases. In addition, osteoprotegerin may contribute to the development of vascular disease. Little is known about the association between serum osteoprotegerin levels and the presence or severity of peripheral arterial disease (PAD). The aim of this study was to examine the association between serum osteoprotegerin levels and both the presence as well as the severity of lower extremity arterial disease in patients with type 2 diabetes (T2DM). PATIENTS AND METHODS: The study included 165 consecutive patients with T2DM (57 % males, mean age 65.0 ± 0.7 years). PAD was diagnosed by measurement of the toe-brachial index (TBI). Serum osteoprotegerin was measured using ELISA. RESULTS: The mean osteoprotegerin level was significantly higher in patients with PAD in comparison to patients without PAD (18.2 ± 1.0 vs. 13.1 ± 2.0 pmol/L, p = 0.014). Significant univariate correlations between TBI and osteoprotegerin level (r = -0.308; p < 0.001), age, body mass index, and HDL cholesterol were observed. In the multivariate linear regression analysis, serum osteoprotegerin (ß = -0.005; p = 0.020), higher age, and male gender were significant predictors of TBI. When 25(OH) vitamin D was introduced into the mentioned model, OPG was no longer a significant predictor of TBI and was replaced in the model with vitamin D (ß = 0.009, p = 0.001). This finding suggests a role of OPG as a mediator of the effects of 25(OH) vitamin D. CONCLUSIONS: Serum osteoprotegerin level is significantly associated with both the presence and severity of PAD in patients with T2D. Osteoprotegerin might be a biomarker for the presence of atherosclerotic disease in patients with T2DM.

KCNQ1 gene polymorphism is associated with glycaemic response to treatment with DPP-4 inhibitors.

AIMS: Only afew gene variants were associated with the response to dipeptidylpeptidase-4 inhibitors (DPP4I). KCNQ1 gene variants were previously related both to type 2 diabetes (T2D) and incretin effect. We hypothesized that T2D related KCNQ1 variants would be associated with smaller glucose-lowering effect of DDP4I. METHODS: We performed a retrospective study in 137 Caucasian subjects with T2D who were followed for 6months after initiation of DPP4I treatment. Genotyping for KCNQ1 rs163184 and rs151290 was performed using PCR-HRMA and PCR-RFLP methods, respectively. The main clinical outcome was reduction in HbA1c (ΔHbA1c) after 6-month DPP4I treatment. RESULTS: KCNQ1 rs163184 T>G variant was associated with the response to DPP4I treatment in genetic additive model (ß=-0.30, p=0.022). For each G allele in the rs163184 genotype, we observed a 0.3% (3.3mmol/mol) less reduction in HbA1c during treatment with a DPP4I. Both the GG homozygotes and G-allele carriers had significantly smaller HbA1c reduction in comparison with the TT homozygotes. CONCLUSIONS: KCNQ1 rs163184 T>G variant was associated with a reduced glycaemic response to DPP4I. The difference of 0.6% (6.5mmol/mol) in HbA1c reduction between the TT and GG homozygotes might be of clinical significance if replicated in further studies.

The effect of alfacalcidiol and metformin on metabolic disturbances in women with polycystic ovary syndrome.

BACKGROUND: The aim of this randomized clinical trial (RCT) was to evaluate the effect of vitamin D supplementation in obese, insulin-resistant (IR) and vitamin D-deficient polycystic ovary syndrome (PCOS) women on metabolic abnormalities in comparison to the effect of metformin or combined metformin plus vitamin D therapy. MATERIAL AND METHODS: Thirty-nine PCOS women who fulfilled the inclusion criteria were randomized into three groups and treated with alfacalcidiol, combined alfacalcidiol and metformin therapy and metformin for 6 months. Body weight, body mass index (BMI), waist circumference, total body fat and fat distribution were measured before and after 6 months of treatment. Plasma fasting glucose, insulin, homeostasis model assessment-insulin resistance (HOMA-IR) and lipid profiles were measured at the same time. RESULTS: There was a significant decrease in body weight, BMI, waist circumference, total body fat and serum glucose levels in the metformin group (p<0.05), whereas PCOS women treated with alfacalcidiol did not significantly change their anthropometric and metabolic parameters. A significant decrease in waist circumference (p<0.05) in the group treated with metformin and alfacalcidiol was detected without other significant metabolic changes (all p>0.05). There were no significant changes in metabolic parameters (p>0.05) after vitamin D therapy except for a slight but non-significant trend towards higher high-density lipoprotein (HDL) cholesterol levels (p=0.087). CONCLUSION: We conclude that vitamin D supplementation has no significant effect on anthropometric and metabolic parameters in PCOS women. Metformin has been still the most effective modality for the treatment of metabolic changes in PCOS.

Single nucleotide polymorphisms in the intergenic region between metformin transporter OCT2 and OCT3 coding genes are associated with short-term response to metformin monotherapy in type 2 diabetes mellitus patients.

OBJECTIVES: High variability in clinical response to metformin is often observed in type 2 diabetes (T2D) patients, and it highlights the need for identification of genetic components affecting the efficiency of metformin therapy. Aim of this observational study is to evaluate the role of tagSNPs (tagging single nucleotide polymorphisms) from genomic regions coding for six metformin transporter genes with respect to the short-term efficiency. DESIGN: 102 tagSNPs in 6 genes coding for metformin transporters were genotyped in the group of 102 T2D patients treated with metformin for 3 months. METHODS: Most significant hits were analyzed in the group of 131 T2D patients from Slovakia. Pharmacokinetic study in 25 healthy nondiabetic volunteers was conducted to investigate the effects of identified polymorphisms. RESULTS: In the discovery group of 102 patients, minor alleles of rs3119309, rs7757336 and rs2481030 were significantly nominally associated with metformin inefficiency (P = 1.9 × 10-6 to 8.1 × 10-6). Effects of rs2481030 and rs7757336 did not replicate in the group of 131 T2DM patients from Slovakia alone, whereas rs7757336 was significantly associated with a reduced metformin response in combined group. In pharmacokinetic study, group of individuals harboring risk alleles of rs7757336 and rs2481030 displayed significantly reduced AUC∞ of metformin in plasma. CONCLUSIONS: For the first time, we have identified an association between the lack of metformin response and SNPs rs3119309 and rs7757336 located in the 5' flanking region of the genes coding for Organic cation transporter 2 and rs2481030 located in the 5' flanking region of Organic cation transporter 3 that was supported by the results of a pharmacokinetic study on 25 healthy volunteers.

Variation in the glucose transporter gene SLC2A2 is associated with glycemic response to metformin.

Metformin is the first-line antidiabetic drug with over 100 million users worldwide, yet its mechanism of action remains unclear. Here the Metformin Genetics (MetGen) Consortium reports a three-stage genome-wide association study (GWAS), consisting of 13,123 participants of different ancestries. The C allele of rs8192675 in the intron of SLC2A2, which encodes the facilitated glucose transporter GLUT2, was associated with a 0.17% (P = 6.6 × 10(-14)) greater metformin-induced reduction in hemoglobin A1c (HbA1c) in 10,577 participants of European ancestry. rs8192675 was the top cis expression quantitative trait locus (cis-eQTL) for SLC2A2 in 1,226 human liver samples, suggesting a key role for hepatic GLUT2 in regulation of metformin action. Among obese individuals, C-allele homozygotes at rs8192675 had a 0.33% (3.6 mmol/mol) greater absolute HbA1c reduction than T-allele homozygotes. This was about half the effect seen with the addition of a DPP-4 inhibitor, and equated to a dose difference of 550 mg of metformin, suggesting rs8192675 as a potential biomarker for stratified medicine.

Prevalence of vitamin D deficiency in Slovak women with polycystic ovary syndrome and its relation to metabolic and reproductive abnormalities.

OBJECTIVE: To investigate prevalence of vitamin D deficiency and its relation to clinical, anthropometrical, and biochemical findings in polycystic ovary syndrome (PCOS) and controls. DESIGN: Case-control prospective observational study. SETTINGS: Department of Internal medicine, L.P. University hospital. PATIENT(S): 99 PCOS women and 66 controls. MAIN OUTCOME MEASURE(S): 25-hydroxyvitamin D level (25(OH)D), anthropometric, endocrine, and metabolic parameters in both groups. RESULTS: There was no significant difference in 25(OH)D levels between PCOS women and controls (24.79 ± 10.77 vs 25.07 ± 10.14 ng/ml, p = 0.868) and also in the prevalence of 25(OH)D deficiency in both groups (80 vs 70 %; p = 0.138). Vitamin D-deficient PCOS patients had significantly higher body mass index (BMI), fasting insulin, and homeostasis model assessment-insulin resistance (median [quartiles]: 2.24 [1.38; 3.51] vs 1.23 [0.79; 1.66]; p< 0.05, age-and BMI-adjusted p = 0.036) and borderline higher glycemia (4.7 ± 0.5 vs 4.5 ± 0.4 mmol/l; p = 0.05; p_adj = 0.95) compared with vitamin D-deficient controls. PCOS women with metabolic syndrome (MS) had lower serum 25(OH)D compared with those without MS (20.6 ± 8.3 vs 25.9 ± 11.3 ng/ml, p = 0.049). 25(OH)D correlated positively with high-density lipoprotein cholesterol in all subjects (r = 0.159, p = 0.043) and negatively with luteinizing hormone/follicle-stimulating hormone ratio (r = - 0.211, p = 0.037). CONCLUSION: Insulin resistance and other metabolic abnormalities in PCOS women seem to be related to PCOS rather than to vitamin D deficiency.

A pharmacogenetic association between a variation in calpain 10 (CAPN10) gene and the response to metformin treatment in patients with type 2 diabetes.

PURPOSE: The aim of the present study was to investigate possible associations of the single-nucleotide variants in six genes encoding the key molecules mediating the metformin pharmacodynamic effect with the response to treatment with metformin in patients with type 2 diabetes. METHODS: One hundred forty-eight drug-naïve patients with type 2 diabetes were included in the study. PRKAA1 rs249429, STK11 rs741765, PCK1 rs4810083, PPARGC1A rs10213440, HNF1A rs11086926, and CAPN10 rs3792269 variants were genotyped. The outcomes of the study were treatment success defined by achieving HbA1c <7 % and absolute reduction in HbAlc after 6-month metformin therapy. The relationships between genotypes and outcomes were evaluated in multivariate logistic and linear models. The level of statistical significance after Bonferroni correction was predefined as p<0.0083. RESULTS: The minor G-allele of CAPN10 rs3792269 A>G polymorphism was significantly associated with less treatment success with an odds ratio of 0.27 (95 % CI 0.12-0.62, p=0.002) per variant allele. When the reduction in HbA1c was analyzed as a quantitative trait, G-allele was nominally associated with a smaller reduction in HbA1c (per allele ß=-0.26, 95 % CI -0.50 to -0.02, p=0.032). The reduction in HbA1c in minor allele carriers (24 % of study population) was smaller by 0.3 % in comparison with the major allele homozygotes. CONCLUSIONS: The present study provides the first observation of an association between a variant in CAPN10 gene and the response to metformin therapy in patients with type 2 diabetes. This observation needs to be replicated in further studies in different populations.

Nocturnal intermittent hypoxia predicts prevalent hypertension in the European Sleep Apnoea Database cohort study.

Systemic hypertension is associated with obstructive sleep apnoea syndrome (OSAS) but the pathophysiological mechanisms are incompletely understood. A collaborative European network of 24 sleep centres established a European Sleep Apnoea Database to evaluate cardiovascular morbidity associated with OSAS. 11 911 adults referred with suspected OSAS between March 2007 and September 2013 underwent overnight sleep studies, either cardiorespiratory polygraphy or polysomnography. We compared the predictive value of the apnoea-hypopnoea index (AHI) and 4% oxygen desaturation index (ODI) for prevalent hypertension, adjusting for relevant covariates including age, smoking, obesity, dyslipidaemia and diabetes. Among patients (70% male, mean±sd age 52±12 years), 78% had AHI>5 events·h(-1) and 41% systemic hypertension. Both AHI and ODI independently related to prevalent hypertension after adjustment for relevant covariates (p<0.0001 for linear trend across quartiles (Q) of severity for both variables). However, in multiple regression analysis with both ODI and AHI in the model, ODI was, whereas AHI was not, independently associated with prevalent hypertension: odds ratios (95% CI) for Q4 versus Q1 regarding ODI were 2.01 (1.61-2.51) and regarding AHI were 0.92 (0.74-1.15) (p<0.0001 and p=0.3054, respectively). This cross sectional study suggests that chronic intermittent hypoxia plays an important role in OSAS-related hypertension.

Effects of apolipoprotein E genotype on serum lipids in obstructive sleep apnoea.

There is increasing evidence that intermittent hypoxia resulting from obstructive sleep apnoea (OSA) is independently associated with dyslipidaemia. Currently, no data exist on potential links between OSA-related dyslipidaemia and susceptibility genes for dyslipidaemia in such patients. Our aim was to study the effects of the apolipoprotein E (APOE) genotype and sleep apnoea severity on atherogenic dyslipidaemia in patients with OSA. 519 clinically stable subjects prospectively recruited at a tertiary referral teaching hospital underwent full polysomnography. APOE gene polymorphisms were assessed using real-time PCR. In all APOE genotype groups, serum triglycerides increased while high-density lipoprotein (HDL) cholesterol was reduced with increasing severity of OSA in each APOE genotype group, whereas the deleterious effects of OSA on serum apolipoprotein (Apo)B levels were observed in ε2 carriers and the ε3/ε3 genotype only. Nevertheless, the ε4 allele carriers had ApoB levels within the risk range, irrespective of nocturnal hypoxia. In addition, among patients with the high-risk ε4 genotype, those with the most severe nocturnal hypoxia had significantly higher triglyceride and lower HDL cholesterol levels compared with nonhypoxic ε4 subjects. APOE genotype and the oxygen desaturation index were both independent predictors of serum triglyceride levels (p=0.009 and p<0.001, respectively; R(2)=0.148) and ApoB levels (p=0.001 and p=0.003, respectively; R(2)=0.104). Our findings suggest that OSA has adverse effects on several lipid parameters over and above the effects carried by APOE genotype. Further st1udies are needed to analyse the effects of high-risk genotypes on metabolic and cardiovascular outcomes in patients with OSA.

Occupational rhinitis in the Slovak Republic--a long-term retrospective study.

BACKGROUND: Allergic and non-allergic rhinitis ranks among the common occupational health problems. However, data on the incidence of occupational rhinitis are lacking, since comprehensive studies are rare. METHODS: The study includes a group of patients in the Slovak Republic who were reported as having occupational rhinitis in the years 1990-2011. The following parameters were tracked in the investigated sample: age, gender, number of cases by individual years, occupations, causative factors and the length of exposure to the given agent. Possible progression of rhinitis to bronchial asthma was evaluated as well. The diagnostic algorithm was also analysed retrospectively, which included skin tests, the examination of specific IgE antibodies and nasal provocation tests. RESULTS: A total of 70 cases of occupational rhinitis were reported. The disease most often occurred in food industry workers (50% of cases). The most common aetiological factor was flour. Among other relatively common allergens were synthetic textile, wool, cotton and different types of moulds. Significant agents were also different chemical factors causing allergic and irritant rhinitis. The average length of exposure was 14.8 years. Exposure was shorter in men than in women (11 years vs. 16 years) (p = 0.04). Bronchial asthma as a comorbidity was diagnosed in 13 patients (19.7%). The critical diagnostic method on the basis of which the causal association between rhinitis and work environments was confirmed in 59% of cases was skin test; confirmation of the occupational cause using nasal provocation test was less frequent (18%). CONCLUSION: Food industry, textile industry and agriculture were the most risky occupational environments. Workers in these sectors require preventive intervention. In case of showing rhinitis symptoms it is necessary to confirm the occupational aetiology of the disease by the objective diagnostic methods. Since occupational rhinitis mostly precedes the occupational asthma, the elimination from the workplace is necessary.

Association between TCF7L2 Genotype and Glycemic Control in Diabetic Patients Treated with Gliclazide.

Previous studies showed associations between variants in TCF7L2 gene and the therapeutic response to sulfonylureas. All sulfonylureas stimulate insulin secretion by the closure of ATP-sensitive potassium (KATP) channel. The aim of the present study was to compare TCF7L2 genotype specific effect of gliclazide binding to KATP channel A-site (Group 1) with sulfonylureas binding to AB-site (Group 2). A total of 101 patients were treated with sulfonylureas for 6 months as an add-on therapy to the previous metformin treatment. TCF7L2 rs7903146 C/T genotype was identified by real-time PCR with subsequent melting curve analysis. Analyses using the dominant genetic model showed significantly higher effect of gliclazide in the CC genotype group in comparison with combined CT + TT genotype group (1.32 ± 0.15% versus 0.73 ± 0.11%, P (adj) = 0.005). No significant difference in ΔHbA1c between the patients with CC genotype and the T-allele carriers was observed in Group 2. In the multivariate analysis, only the TCF7L2 genotype (P = 0.006) and the baseline HbA1c (P < 0.001) were significant predictors of ΔHbA1c. After introducing an interaction term between the TCF7L2 genotype and the sulfonylurea type into multivariate model, the interaction became a significant predictor (P = 0.023) of ΔHbA1c. The results indicate significantly higher difference in ΔHbA1c among the TCF7L2 genotypes in patients treated with gliclazide than in patients treated with glimepiride, glibenclamide, or glipizide.

KCNJ11 gene E23K variant and therapeutic response to sulfonylureas.

AIMS: Potassium inwardly rectifier 6.2 subunit (Kir6.2) of the ATP-sensitive potassium (K(ATP)) channel encoded by KCNJ11 gene is a therapeutical target for sulfonylureas. KCNJ11 E23K polymorphism was associated with type 2 diabetes in genetic association studies. The aim of the present pharmacogenetic study was to examine the effect of sulfonylurea treatment on glycemic control in relationship to KCNJ11 E23K variant. PATIENTS AND METHODS: One hundred and one patients with type 2 diabetes who failed to achieve HbA1c<7% on previous metformin monotherapy were included to the study. Sulfonylurea drug was given in addition to metformin. The main outcome of the study was reduction in HbA1c level (ΔHbA1c) after 6-month sulfonylurea therapy. KCNJ11 genotypes were determined by real-time PCR with melting curve analysis. RESULTS: After 6-month treatment, KCNJ11 K-allele carriers had higher decrease in HbA1c compared with EE homozygotes in the dominant genetic model (1.04±0.10 vs. 0.79±0.12%, p=0.036). In the log-additive model, greater mean reduction in HbA1c by 0.16% (95% CI 0.01-0.32, p=0.038) per each K-allele was observed. The relationship of treatment response with KCNJ11 genotype was also significant in the biggest subgroup of patients treated with gliclazide (n=55). CONCLUSIONS: Carriers of the KCNJ11 K-allele have better therapeutic response to gliclazide. This observation might help to identify patients who will have the highest benefit from sulfonylurea treatment.

Variation in KCNQ1 is associated with therapeutic response to sulphonylureas.

BACKGROUND: We aimed to analyse quantitative effects of treatment with sulphonylurea in addition to metformin on parameters of glycemic control in relation to KCNQ1 genotypes, and to identify factors predictive for the response to sulphonylurea treatment. MATERIAL/METHODS: Effect of 6-month sulphonylurea therapy in addition to metformin on glycemic control according to KCNQ1 genotypes was evaluated in 87 patients with type 2 diabetes who failed to achieve glycemic control on metformin monotherapy. KCNQ1 rs163184 (T>G) polymorphism was determined by real-time PCR with melting analysis of unlabeled probe. RESULTS: The reduction in fasting plasma glucose (ΔFPG) after 6-month sulphonylurea therapy significantly differed among 3 KCNQ1 genotype groups (ANOVA, p=0.017). In a recessive genetic model, carriers of the T-allele (TT+TG) achieved significantly lower FPG levels in comparison with patients with the GG genotype (6.95 ± 0.13 vs. 7.50 ± 0.21 mmol/L, p=0.033). Consequently, ΔFPG was significantly higher in the TT+TG group compared to the GG group (1.58 ± 0.13 vs. 1.04 ± 0.18 mmol/L, p=0.016). In multiple linear regression analysis KCNQ1 genotype (p=0.016) and baseline FPG (p<0.001) were the only significant independent predictors of ΔFPG (R2=0.48). CONCLUSIONS: Our results suggest that the magnitude of FPG reduction after 6-month sulphonylurea treatment in addition to metformin in patients with type 2 diabetes is related to the variation in KCNQ1. The FPG response to sulphonylureas was significantly lower in carriers of the risk GG genotype.

Relationship between osteoporosis and adipose tissue leptin and osteoprotegerin in patients with chronic obstructive pulmonary disease.

INTRODUCTION: The role of fat-bone interactions in the pathogenesis of osteoporosis in chronic obstructive pulmonary disease (COPD) is poorly understood. Our aim was to investigate expressions of leptin and osteoprotegerin (OPG) in the adipose tissue, and their relationships to osteoporosis in patients with COPD. METHODS: In 39 patients with stable COPD, bone mineral density (BMD) and body composition was assessed by Dual Energy X-Ray Absorptiometry. Serum leptin was determined by the enzyme-linked immunosorbent assay, and bone turnover markers osteocalcin and ß-crosslaps by the electrochemiluminiscence immunoassays. Subcutaneous adipose tissue samples were analyzed using real-time PCR. RESULTS: Twenty-one patients without, and 18 with osteoporosis were enrolled (35 men; age 62.2 ± 7.3years). Compared to patients without osteoporosis, those with the disease had significantly lower serum levels and adipose tissue expressions of leptin, in association with increased serum ß-crosslaps (p=0.028, p=0.034, p=0.022, respectively). Log adipose tissue leptin was inversely related to serum ß-crosslaps (p=0.015), and directly to serum leptin (p<0.001) and to the total, femoral, and lumbar BMD and T-score (p<0.02 for all relationships). Adipose tissue OPG expression was related to all variables of bone density except for lumbar BMD and T-score (p<0.05 for all relationships). Log adipose tissue leptin and OPG expressions predicted femoral T-score independently of age, gender and pulmonary function (p<0.001, adjusted R(2)=0.383; p=0.008, adjusted R(2)=0.301, respectively). Introducing body mass (or fat mass) index into these models eliminated independent predictive value of leptin and OPG expressions. CONCLUSION: Our results suggest that adipose tissue leptin and OPG expressions are related to osteoporosis in patients with COPD, and appear to act as mediators between fat mass and BMD.

Changes in insulin sensitivity and insulin release in relation to glycemia and glucose tolerance in 6,414 Finnish men.

OBJECTIVE: We evaluated insulin sensitivity and insulin secretion across the entire range of fasting (FPG) and 2-h plasma glucose (PG), and we investigated the differences in insulin sensitivity and insulin release in different glucose tolerance categories. RESEARCH DESIGN AND METHODS: A total of 6,414 Finnish men (aged 57 +/- 7 years, BMI 27.0 +/- 3.9 kg/m2) from our ongoing population-based METSIM (Metabolic Syndrome in Men) study were included. Of these subjects, 2,168 had normal glucose tolerance, 2,859 isolated impaired fasting glucose (IFG), 217 isolated impaired glucose tolerance (IGT), 701 a combination of IFG and IGT, and 469 newly diagnosed type 2 diabetes. RESULTS: The Matsuda index of insulin sensitivity decreased substantially within the normal range of FPG (-17%) and 2-h PG (-37%) and was approximately -65 and -53% in the diabetic range of FPG and 2-h PG, respectively, compared with the reference range (FPG and 2-h PG <5.0 mmol/l). Early-phase insulin release declined by only approximately -5% within the normal range of FPG and 2-h PG but decreased significantly in the diabetic range of FPG (by 32-70%) and 2-h PG (by 33-51%). Changes in insulin sensitivity and insulin secretion in relation to hyperglycemia were independent of obesity. The predominant feature of isolated IGT was impaired peripheral insulin sensitivity. Isolated IFG was characterized by impaired early and total insulin release. CONCLUSIONS: Peripheral insulin sensitivity was already decreased substantially at low PG levels within the normoglycemic range, whereas impairment in insulin secretion was observed mainly in the diabetic range of FPG and 2-h PG. Obesity did not affect changes in insulin sensitivity or insulin secretion in relation to hyperglycemia.

Lipoprotein lipase HindIII polymorphism influences HDL-cholesterol levels in statin-treated patients with coronary artery disease.

BACKGROUND: HDL-cholesterol (HDL-C) is a recognized athero-protective factor and low levels of HDL-C occur frequently in patients with coronary artery disease. Regulation of HDL-C level most probably results from the interaction of genes involved in lipoprotein metabolism and also from non-genetic factors. We studied associations and interactions among HindIII polymorphisms of the lipoprotein lipase gene LPL and selected non-genetic factors with respect to HDL-C levels in patients with coronary artery disease. PATIENTS AND METHODS: 288 Slovak patients (35% women) with documented coronary artery disease, age (mean +/- SEM) 60 +/- 1 years and BMI 29 +/- 0.3 kg/m(2), were examined and genotyped for LPL HindIII (rs320) using a PCR/RFLP method. HDL-C levels were determined in a direct enzymatic assay. RESULTS: In the sample overall there were no significant differences across the LPL genotypes in adjusted HDL-C levels or in other lipids, although a trend toward higher HDL-C and lower triglycerides in H-H- homozygotes was observed. Multiple linear regression identified a significant interaction between LPL HindIII and statin treatment, which together with sex and diabetes explained 12.1% of HDL-C variance. Accordingly, in statin-treated patients we observed significant stepwise increments of the HDL-C level related to the increasing number of H- alleles (P = 0.04 for linear trend), whereas no such association was observed in patients without hypolipidemic treatment. H-H- homozygotes had a 16% (0.19 mmol/l) higher level of HDL-C than the H+H+ homozygotes (P = 0.06). CONCLUSION: HDL-C may be influenced by an interaction between statin treatment and LPL HindIII genotype. However, the effect of this interaction appears to be small when compared with the effect of non-genetic factors. This finding requires replication in a pharmacogenetic study.