1,5-Anhydroglucitol as a marker of maternal glycaemic control and predictor of neonatal birthweight in pregnancies complicated by type 1 diabetes mellitus.

AIMS/HYPOTHESIS: Most pregnant women with type 1 diabetes mellitus achieve HbA1c targets; however, macrosomia remains prevalent and better pregnancy glycaemic markers are therefore needed. 1,5-Anhydroglucitol (1,5-AG) is a short-term marker of glycaemia, reflecting a period of 1 to 2 weeks. Its excretion rate depends on the renal glucose threshold and thus it is unclear whether it may be used in pregnant type 1 diabetes women. We evaluated 1,5-AG as a glycaemic marker and birthweight predictor in pregnant women with type 1 diabetes, and compared its performance with HbA1c. METHODS: 1,5-AG and HbA1c were measured in 82 pregnant women with type 1 diabetes. In addition, 58 continuous glucose monitoring system (CGMS) records were available. Macrosomia was defined as birthweight >90th centile. The data were analysed with Pearson's correlations, and linear and logistic regression models. Receiver operating characteristic (ROC) analysis was used to evaluate third trimester 1,5-AG as a predictor of macrosomia. RESULTS: Unlike HbA1c, 1,5-AG strongly correlated with CGMS indices: the AUC above 7.8 mmol/l (r = -0.66; p < 0.001), average maximum glucose (r = -0.58; p < 0.001) and mean glucose (r = -0.54; p < 0.001). In the third trimester, 1,5-AG was the strongest predictor of macrosomia, with ROC AUC 0.81 (95% CI 0.70, 0.89). In contrast, HbA1c in the third trimester had a ROC AUC of 0.69 (95% CI 0.58, 0.81). The best discrimination was achieved when both markers were used jointly, yielding a ROC AUC of 0.84 (95% CI 0.76, 0.93). CONCLUSIONS/INTERPRETATION: In pregnant women with type 1 diabetes, 1,5-AG is a better glycaemic marker than HbA1c, as assessed by CGMS. A decreased third trimester 1,5-AG level, either singly or with HbA1c, is a strong predictor of macrosomia.

Altered fibrin-clot properties are associated with retinopathy in type 2 diabetes mellitus.

AIM: The development and progression of diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) have been associated with poor glycaemic control, long disease duration and other clinical features. However, the pathogenesis of the complication is still poorly understood. As the formation of dense fibrin clots resistant to lysis has been described in diabetes patients, this study tested the hypothesis that altered clot structure and function are associated with DR in T2DM patients. METHODS: The study included 101 T2DM subjects without DR (NDR) and 60 with DR. Plasma fibrin-clot permeation was assessed using a pressure-driven system, and expressed as the permeation coefficient (K(s)), indicating pore size, and as the time required for a 50% decrease in clot turbidity (t(50%)) as a marker of susceptibility to fibrinolysis. All patients underwent ophthalmological examination. Clinical and biochemical co-variables were also measured. Determinants of DR were identified using stepwise, multivariable, logistic-regression analyses. RESULTS: Patients with DR had lower clot permeability (K(s): 6.15 ± 1.18 vs. 7.53 ± 1.24 10(-9) cm(2); P < 0.0001) and slower fibrin-clot lysis (t(50%): 10.12 ± 1.24 vs. 9.12 ± 1.4 min; P < 0.0001) than NDR subjects. Logistic analysis revealed associations between DR and K(s), t(50%), fasting glucose and diabetes duration, as well as insulin treatment and statin non-use (P < 0.05). After adjusting for these variables as well as for age and gender, associations between K(s) and t(50%) with DR proved to be significant. CONCLUSION: Formation of compact fibrin clots and impaired clot lysis are both associated with DR in T2DM patients. However, it is unclear whether these abnormalities lead to the development of DR or merely constitute a marker of its presence.

Retinopathy in type 2 diabetes mellitus is associated with increased intima-media thickness and endothelial dysfunction.

BACKGROUND: Microangioathy and macroangiopathy in type 2 diabetes mellitus (T2DM) frequently coexist. Both types of vascular complications share traditional risk factors. It is not clear whether the presence of microangiopathy, such as diabetic retinopathy (DR), constitutes a predictor of atherosclerosis in T2DM. Here we described the search for the association between DR and intima-media thickness (IMT) in T2DM. We also compared endothelial function in subjects with and without DR. MATERIAL AND METHODS: We examined 182 consecutive patients with T2DM for at least 5 years (mean age at examination 56.3 +/- 6.52 years). We assessed (i) IMT of carotid artery by ultrasound and (ii) endothelial function by flow-mediated dilatation (FMD) method as well as by measurement of concentrations of von Willebrand factor (vWF) and s-ICAM-1. All patients underwent ophthalmological examination. Statistical analysis included Student's, Mann-Whitney, chi-square, Fisher tests and multiple regression. RESULTS: DR was found in 71 (39.0%) subjects. IMT was higher in patients with DR than those without DR (0.87 mm vs. 0.79 mm, respectively, P = 0.0001). FMD was lower in the complication group than in subjects without DR (8.38% vs. 10.45%, respectively, P = 0.0023). Concentrations of s-ICAM-1 and vWF were not different between the groups. In multiple regression analysis, DR was among the predictors of increased IMT (P = 0.016) and decreased FMD (P = 0.002). We did not find a significant association of DR with vWF and s-ICAM-1 (P = 0.09 and P = 0.11, respectively). CONCLUSIONS: DR is associated with increased IMT and endothelial dysfunction in T2DM. Impaired endothelial function may be a common denominator of pathogenesis of microvascular complications and atherosclerosis in T2DM.

Molecular background and clinical characteristics of HNF1A MODY in a Polish population.

PURPOSE: Knowing the molecular background of monogenic diabetes in affected individuals influences the clinical practice. Mutations in the HNF1A gene are the most frequent cause of MODY. The aim of the present study was to identify the genetic and clinical characteristics of HNF1A MODY in a Polish population, and the prevalence of diabetic complications and renal malformations. METHODS: We identified 47 families with the early-onset, autosomal-dominant form of diabetes that met the criteria of MODY. Mutation screening involved direct sequencing of the HNF1A gene. Patients' characteristics included clinical data, anthropometric measurements and biochemical parameters. The search for renal malformations involved ultrasound examination of all HNF1A mutation carriers. RESULTS: We identified 13 HNF1A MODY families and examined 56 mutation carriers, including 46 diabetic patients. The average HbA(1c) level among the diabetics was 7.5%. We identified diabetic retinopathy in 47.7% of the MODY patients, while diabetic nephropathy was present in 25%. In five HNF1A mutation carriers from three families, renal developmental malformations were identified, including one functioning kidney in two (3.6%) of them. CONCLUSION: This first systematic search for HNF1A mutations in a Polish population revealed that they are a frequent cause of MODY. In this population, HNF1A mutation carriers were characterized by a high prevalence of diabetic complications. In addition, renal developmental abnormalities were found in some mutation carriers.

Total plasma homocysteine correlates in women with gestational diabetes.

AIM: We aim to assess serum total homocysteine (tHcy) associations with metabolic syndrome components and B-vitamins in women with gestational diabetes mellitus (GDM). METHODS: We studied 61 consecutive pregnant women, 44 with GDM and 17 with normal glucose tolerance (CG). Serum homocysteine levels were analyzed by ELISA, using Bio-Rad reagents. Serum folates and vitamin B(12) concentrations were determined by chemiluminescent immunoassay, free fatty acids (FFA) and lipids enzymatically. RESULTS: Serum homocysteine levels were similar in both the GDM and the CG groups (8+/-2.0 vs 7.4+/-1.1 micromol/l, respectively). Women with GDM in comparison to CG women were characterized by higher values of homeostasis model of insulin resistance (HOMA-IR) (2.8+/-1.7 vs 1.6+/-0.9, P<0.01), serum triglycerides (2.7+/-0.9 vs 1.9+/-0.5 mmol/l, P<0.01) and FFA (0.6+/-0.2 vs 0.46+/-0.2 mmol/l, P<0.05). In GDM women serum tHcy correlated with vitamin B(12) (r= -0.47, P<0.01) and folates (r= -0.51, P<0.001); in CG women with HOMA-IR, a marker of insulin resistance (r= -0.49, P<0.05). In multiple regression analysis with serum tHcy as a dependent variable, folate and vitamin B(12) entered the analysis in GDM women (beta= -0.42 and -0.34, respectively, P<0.05), whereas in CG cystatin C and HOMA-IR entered the analysis (P<0.05). CONCLUSIONS: In women with GDM, serum homocysteine is significantly associated with vitamin B(12) and folate levels, while in healthy pregnant women with HOMA-IR and with kidney function. The results suggest the importance of the B-group vitamins in regulation of serum tHcy levels in women with insulin resistance/gestational diabetes, what might be relevant in protection against pregnancy complications associated with elevated tHcy in GDM women.

Clinical risk factors and the role of VDR gene polymorphisms in diabetic retinopathy in Polish type 2 diabetes patients.

Evidence exists that some clinical, metabolic and genetic risk factors are associated with the development of diabetic retinopathy (DR). The aim of the study was: (1) to define the prevalence of DR in the examined group of 267 patients with type 2 diabetes mellitus (T2DM) from a Polish population; (2) to identify in cross-sectional analysis, the clinical features associated with DR in the study group; and (3) to search for the association of 4 markers of vitamin D receptor (VDR), a candidate gene for vascular complications in diabetes, with DR. The examined group consisted of 146 female and 121 male T2DM patients (mean age at examination: 61.3+/-9.4 years; age at T2DM diagnosis: 50.0+/-9.2; T2DM duration: 11.3+/-7.8 years; body mass index (BMI): 30.5+/-5.5 kg/m(2); HbA1c: 7.8+/-1.5%). In all patients, the clinical and metabolic profile was determined. Diagnosis of DR was determined by a trained ophthalmologist by ophthalmoscopy after pupillary dilatation. Colour photographic documentation was made. The examined T2DM patients were genotyped for FokI, ApaI, BsmI and TaqI frequent VDR polymorphisms based on the restriction fragment length polymorphism method. The statistical analysis was performed using univariate and multivariate logistic regression (SAS) and haplotype analysis (Haplostat). DR was detected in 85 (31.8%) patients with T2DM. The multivariate analysis revealed that significant predictors of this complication were: never-smoking status (odds ratio 2.2, 95% confidence interval 1.2-4), urea serum level (1.3, 1.1-1.5), HbA1c level (1.4, 1.1-1.8) and insulin treatment (2.7, 1.4-5.1). Other features such as age of T2DM diagnosis, T2DM duration prior to ophthalmic exam, obesity (BMI>30), serum creatinine level, albumin/creatinine ratio and arterial hypertension were univariate predictors of DR, however they lost significance as independent predictors in multivariate analysis. Similarly, the alleles, genotypes, haplotype and haplotype combination of VDR were not associated with the examined complication. However, there was a suggestion of a possible slight association between the fbaT haplotype and DR (p=0.11). In conclusion, our study showed that DR in T2DM patients remains a frequent complication in Polish T2DM patients. We were able to confirm the role of some clinical risk factors, surprisingly including not-smoking status, as was previously shown in the UK Prospective Diabetes Study (UKPDS). VDR gene polymorphisms did not constitute a risk factor for this size of study group.

The Ala45Thr polymorphism of BETA2/NeuroD1 gene and susceptibility to type 2 diabetes mellitus in a Polish population.

The BETA2/NeuroD1 gene product is a transcription factor, a member of a helix-loop-helix (HLH) family that is specifically expressed in the endocrine pancreas. HLH and homeobox proteins are involved in the development and function of pancreatic islets cells. Mice homozygous for a targeted disruption of BETA2/NeuroD1 showed abnormal pancreatic islet morphogenesis and developed overt diabetes. Mutations in the NeuroD/BETA2 gene were linked to the development of type 2 diabetes (T2DM). The aims of the study were to determine the allele and genotype frequency of Ala45Thr polymorphism of BETA2/NeuroD1 in a Polish population and to examine the role of this amino acid variant in the genetic susceptibility to T2DM. We included 394 individuals into this study: 223 T2DM patients with the age at diagnosis above 35 years and 171 controls without a family history of T2DM. The fragment of the gene, corresponding to the Ala45Thr amino acid variant, was amplified by polymerase chain reaction. Alleles and genotypes were determined based on electrophoresis of the specific restriction enzyme EcoI57 DNA digestion products. Differences in distribution between the groups were examined by chi(2) test. The frequencies of the Ala and Thr alleles in T2DM patients (62% and 37.9%) were similar to those in the controls (65.5% and 34.5%; p=0.32). Similarly, there was no difference between the groups when we analyzed the genotype distribution (p=0.24). The stratification analysis based on family history of T2DM, obesity, and age of diagnosis did not show any difference between the groups. In conclusion, the frequency of Ala45Thr polymorphism in this studied Polish population is similar to its frequency in other Caucasians. We did not find evidence that the Ala45Thr polymorphism of BETA2/NeuroD1 played a role in the risk of T2DM in the examined Polish population.

Search for mitochondrial A3243G tRNA(Leu) mutation in Polish patients with type 2 diabetes mellitus.

BACKGROUND: The influences of genetic and environmental factors form a clinical picture of type 2 diabetes mellitus. Genetic studies of type 2 diabetes mellitus become increasingly important. The knowledge of the molecular background of type 2 diabetes has been growing rapidly over recent years. One of the forms of the disease defined on the molecular level is maternally inherited type 2 diabetes mellitus. This diabetes, which is frequently accompanied by hearing impairment of deafness (maternally inherited diabetes with deafness-MIDD), was linked with sequence differences in mitochondrial DNA. The most frequent cause of MIDD is A3243G substitution in a mitochondrial tRNA(Leu) gene. While this mutation was identified in different races in several populations, it is still important and valuable to evaluate its prevalence in various ethnic groups. The aim of the project was to determine the prevalence of A3243G substitution in a mitochondrial tRNA(Leu) gene among Polish diabetic subjects. MATERIAL AND METHODS: In total 129 individuals, with type 2 diabetes and 12 with gestational diabetes were selected for this study. Two techniques based on restriction fragment length polymorphism (RFLP) method were used to screen for A3243G mutation. In the first approach, non-radioactive PCR reactions of mitochondrial DNA region of interest were performed using DNA of the study participants. This was followed by Apa I restriction enzyme digestion of the PCR product. Subsequently an electrophoretic separation was done on 2% agarose gel with ethidium bromide staining. In the second, more sensitive, modification of RFLP, [alpha 32P]dCTP was used for internal primer labeling and the electrophoresis was done on acrylamide gel. A positive sample was used to control the quality of the genotyping. RESULTS: In both approaches none of the samples, except for the positive control, showed the evidence of the G variant. CONCLUSIONS: In summary, the A3243G mutation in mitochondrial tRNA(Leu) gene is not a frequent cause of diabetes in the Polish population. Further screening of enlarging study group is necessary to fully determine the prevalence of this mutation in our population. This, together with the search for other mitochondrial mutations, should allow to fully determine the prevalence of MIDD and its specific molecular background in the Polish population.

Identification of a new mutation in the hepatocyte nuclear factor-1alpha gene in a Polish family with early-onset type 2 diabetes mellitus.

Recently, several genes associated with early-onset, autosomal dominant Type 2 diabetes (MODY) have been identified. Mutations in the hepatocyte nuclear factor (HNF)-1alpha gene seem to account for a substantial proportion of this type of diabetes in several populations. However, it is still of interest to estimate the frequency of HNF-1alpha mutations in various ethnic groups. The aim of our study was to determine the contribution of the HNF-1alpha gene to the development of MODY in a Polish population. We selected 15 families with MODY for this project. The 10 exons and promoter region of the gene were screened for sequence differences by direct sequencing of probands DNA. We detected 7 previously described polymorphisms that were not associated with diabetes. However, one sequence difference, a deletion of a cytosine in codon 225 in exon 3 (designated S225fdelC), was a new mutation resulting in a frame shift and synthesis of a nonsense peptide from amino acid 225 to 232 followed by the stop codon. Thus, the S225fdelC mutation effectively caused the loss of a part of the DNA binding domain and the entire transactivation domain. This mutation was present in 4 affected members of the family. They developed diabetes at an early age (mean age at diagnosis 23 yr) and were characterized by severely impaired insulin secretion. In addition, one family member who was not a carrier of the S225fdelC mutation was diagnosed with diabetes. Thus, he represents an example of phenocopy. In conclusion, we have identified a new HNF-1alpha variant that represents the first MODY mutation described in a Polish population. MODY3 mutations, including those in the exon 4 "hot spot", do not appear to be a very common cause of MODY in the Polish population.

[Menopause and hormone replacement therapy (HRT) in women with diabetes]. / Menopauza i hormonoterapia zastepcza (HTZ) u kobiet z cukrzyca.

This review is based on publications from 1996-1998 concerned research into hormone replacement therapy (HRT) estimated effect on metabolic factors in diabetic women. Coronary heart disease (CHD) and myocardial infarction are the main reasons of death in postmenopausal women. Evidence from many observational studies suggests that estrogen replacement therapy diminishes the mortality of healthy women due to CHD. Diabetes mellitus is an independent risk factor of CHD. The results of research show that estrogen replacement therapy decreases the death risk of myocardial infarction in diabetic women, too. Transdermal estrogens have beneficial effect on carbohydrate metabolism, attenuate glycemic control and decrease insulin resistance. We can observe favourable changes in fat distribution resulting in decreasing abdominal obesity. Diabetic women do not appear to experience as great changes in lipid profile response with HRT as do non-diabetic women. Women with diabetes had proportionally lower hormone-related decrease in total cholesterol and LDL cholesterol levels and increased HDL cholesterol level. The extent to which the beneficial effect of estrogen on lipoproteins is reversed depends on the type and dose of progestin added. Now, using HRT as secondary prevention of CHD in diabetic women, after consideration of an individual risk factor is recommended. We recommend preparations of 17 beta-estradiol administered transdermally and selected gestagens like dydrogesterone, norethisterone, medroxyprogesterone in small dosage.