DNA methylation analysis of negative pressure therapy effect in diabetic foot ulcers.

OBJECTIVE: Negative pressure wound therapy (NPWT) has been used to treat diabetic foot ulcerations (DFUs). Its action on the molecular level, however, is only partially understood. Some earlier data suggested NPWT may be mediated through modification of local gene expression. As methylation is a key epigenetic regulatory mechanism of gene expression, we assessed the effect of NPWT on its profile in patients with type 2 diabetes (T2DM) and neuropathic non-infected DFUs. METHODS: Of 36 included patients, 23 were assigned to NPWT and 13 to standard therapy. Due to ethical concerns, the assignment was non-randomized and based on wound characteristics. Tissue samples were obtained before and 8 ± 1 days after therapy initiation. DNA methylation patterns were checked by Illumina Methylation EPIC kit. RESULTS: In terms of clinical characteristics, the groups presented typical features of T2DM; however, the NPWT group had significantly greater wound area: 16.8 cm2 vs 1.4 cm2 (P = 0.0003). Initially only one region at chromosome 5 was differentially methylated. After treatment, 57 differentially methylated genes were found, mainly located on chromosomes 6 (chr6p21) and 20 (chr20p13); they were associated with DNA repair and autocrine signaling via retinoic acid receptor. We performed differential analyses pre treatment and post treatment. The analysis revealed 426 differentially methylated regions in the NPWT group, but none in the control group. The enrichment analysis showed 11 processes significantly associated with NPWT, of which 4 were linked with complement system activation. All but one were hypermethylated after NPWT. CONCLUSION: The NPWT effect on DFUs may be mediated through epigenetic changes resulting in the inhibition of complement system activation.

Negative-pressure wound therapy for management of chronic neuropathic noninfected diabetic foot ulcerations - short-term efficacy and long-term outcomes.

PURPOSE: Negative pressure wound therapy (NPWT) is an adjunct method used in the treatment of diabetic foot ulceration (DFU). Real world data on its effectiveness and safety is scarce. In this prospective observational study, we assessed the short-term efficacy, safety, and long-term outcomes of NPWT in patients with type 2 diabetes (T2DM) and neuropathic, noninfected DFUs. METHODS: Based on wound characteristics, mainly area (>1 vs. ≤1 cm2), 75 patients with DFUs treated in an outpatient clinic were assigned to NPWT (n = 53) or standard therapy (n = 22). Wound area reduction was evaluated after 8 ± 1 days. Long-term outcomes assessed included complete ulceration closure and recurrence rate. RESULTS: Patients assigned to NPWT were characterized by greater wound area (15.7 vs. 2.9 cm2). Reduction in wound area was found in both the NPWT (-1.1 cm2, -10.2%, p = 0.0001) and comparator group (-0.3 cm2, -18.0%, p = 0.0038). No serious adverse events related to NPWT were noted. Within 1 year, 55.1% (27/49) of DFUs were closed in the NPWT group and 73.7% (14/19) in the comparator group (p = 0.15). In the logistic regression, wound duration and smaller initial area, but not treatment mode, were associated with closure. One-year follow-up after DFU resolution revealed an ~30.0% recurrence rate in both groups (p = 0.88). CONCLUSIONS: NPWT is a safe treatment for neuropathic, nonischemic, and noninfected DFU in patients with T2DM, although this observational study did not prove its effectiveness over standard therapy. Additionally, we report a high rate of both closure and recurrence of ulcers, the latter irrespective of initial ulcer area.

How much of the predisposition to Hashimoto's thyroiditis can be explained based on previously reported associations?

PURPOSE: Our insight in the genetics of Hashimoto's thyroiditis (HT) has become clearer through information provided by genome-wide association studies and candidate gene studies, but remains still not fully understood. Our aim was to assess how many different genetic risk variants contribute to the development of HT. METHODS: 147 HT cases (10.2% men) and 147 controls (13.6% men) were qualified for the analysis. Intrinsic and environmental factors were controlled for. Polymorphisms (SNP) were chosen based on the literature and included markers of the genes PTPN22, CTLA4, TG, TPO among others, and of genomic regions pointed by GWAS studies. SNP were typed on a microarray. Variants in the HLA-DRB1 gene were identified by Sanger sequencing. RESULTS: Multivariate predisposition to HT was modeled. Based on the investigated group, a model of seven variables was obtained. The variability explained by this model was assessed at only 5.4821% (p = 2 × 10-6), which indicates that many dozens of factors are required simultaneously to explain HT predisposition. CONCLUSIONS: We analyzed genetic regions commonly and most significantly associated with autoimmune thyroid disorders in the literature, on a carefully selected cohort. Our results indicated a lack of possibility to predict the risk of HT development, even with a multivariate model. We therefore conclude that strong associations of single genetic regions with HT should be interpreted with great caution. We believe that a change in the attitude towards genetic association analyses of HT predisposition is necessary. Studies including multiple factors simultaneously are needed to unravel the intricacies of genetic associations with HT.

A single dose of dapagliflozin, an SGLT-2 inhibitor, induces higher glycosuria in GCK- and HNF1A-MODY than in type 2 diabetes mellitus.

AIMS: SGLT2 inhibitors are a new class of oral hypoglycemic agents used in type 2 diabetes (T2DM). Their effectiveness in maturity onset diabetes of the young (MODY) is unknown. We aimed to assess the response to a single dose of 10 mg dapagliflozin in patients with Hepatocyte Nuclear Factor 1 Alpha (HNF1A)-MODY, Glucokinase (GCK)-MODY, and type 2 diabetes. METHODS: We examined 14 HNF1A-MODY, 19 GCK-MODY, and 12 type 2 diabetes patients. All studied individuals received a single morning dose of 10 mg of dapagliflozin added to their current therapy of diabetes. To assess the response to dapagliflozin we analyzed change in urinary glucose to creatinine ratio and serum 1,5-Anhydroglucitol (1,5-AG) level. RESULTS: There were only four patients with positive urine glucose before dapagliflozin administration (one with HNF1A-MODY, two with GCK-MODY, and one with T2DM), whereas after SGLT-2 inhibitor use, glycosuria occurred in all studied participants. Considerable changes in mean glucose to creatinine ratio after dapagliflozin administration were observed in all three groups (20.51 ± 12.08, 23.19 ± 8.10, and 9.84 ± 6.68 mmol/mmol for HNF1A-MODY, GCK-MODY, and T2DM, respectively, p < 0.001 for all comparisons). Post-hoc analysis revealed significant differences in mean glucose to creatinine ratio change between type 2 diabetes and each monogenic diabetes in response to dapagliflozin (p = 0.02, p = 0.003 for HNF1-A and GCK MODY, respectively), but not between the two MODY forms (p = 0.7231). Significant change in serum 1,5-AG was noticed only in T2DM and it was -6.57 ± 7.34 mg/ml (p = 0.04). CONCLUSIONS: A single dose of dapagliflozin, an SGLT-2 inhibitor, induces higher glycosuria in GCK- and HNF1A-MODY than in T2DM. Whether flozins are a valid therapeutic option in these forms of MODY requires long-term clinical studies.

Carotid Plaques Correlates in Patients With Familial Hypercholesterolemia.

Patients with familial hypercholesterolemia (FH) are at increased risk of premature cardiovascular disease. We compared factors associated with the presence of carotid plaques and carotid intima-media thickness (cIMT), markers of subclinical atherosclerosis, in 241 patients with FH (98, 40.7% men; mean age 41 ± 18.4 years). Patients with FH having carotid plaques (36.5%) had mean age, apolipoprotein (apo) B, glucose, apoA1, systolic blood pressure (SBP) and diastolic BP, waist/hip ratio (WHR), and body mass index higher than patients without plaques. Logistic regression revealed that apoB (odds ratio [OR] per 1 unit change 1.03,P= .005), high-density lipoprotein cholesterol (HDL-C; OR per 1 standard deviation [SD] change 0.59,P= .015), and non-HDL-C (OR per 1SD change 1.53,P= .04) were significantly associated with the presence of plaques. The cIMT correlated with obesity parameters, BP, apoB, glucose, high-sensitivity C-reactive protein, creatinine, γ-glutamyl transpeptidase, and alanine transaminase (P< .001). Regression analysis revealed that cIMT was significantly associated with apoB, SBP, and WHR. These results confirm the role of apoB-containing lipoproteins and low HDL-C with the presence of carotid plaques and apoB, BP, and WHR with cIMT.

Markers of Antioxidant Defense in Patients with Type 2 Diabetes.

AIMS: Diabetes is considered a state of increased oxidative stress. This study evaluates blood concentrations of selected markers of antioxidant defense in patients with type 2 diabetes. METHODS: The study included 80 type 2 diabetes patients and 79 apparently healthy controls. Measured markers included ferric reducing ability of plasma (FRAP), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), γ-glutamyltransferase (GGT) and uric acid serum, and plasma and/or hemolysate levels. RESULTS: FRAP, uric acid, CRP, and GGT levels were significantly higher in patients with diabetes. Plasma and hemolysate GR was significantly higher whereas GPx activity was significantly lower in patients with diabetes. There were no significant differences in antioxidant defense markers between patients with and without chronic diabetes complications. Fasting serum glucose correlated with plasma GPx, plasma and hemolysate GR, FRAP, and serum GGT, and HbA1c correlated with serum GGT. Only FRAP and serum uric acid were significantly higher in obese (BMI > 30 kg/m(2)) patients with diabetes than in nonobese patients. CONCLUSIONS: Some components of antioxidant defense such as GR, uric acid, and GGT are increased in patients with type 2 diabetes. However, the whole system cannot compensate for an enhanced production of ROS as reflected by the trend toward decreased erythrocytes GSH.

Prevalence of Retinopathy in Adult Patients with GCK-MODY and HNF1A-MODY.

We aimed to assess the prevalence of diabetic retinopathy (DR) in adult patients with GCK-MODY and HNF1A-MODY in Poland and to identify biochemical and clinical risk factors associated with its occurrence.We examined 74 GCK mutation carriers, 51 with diabetes and 23 with prediabetes, respectively, and 63 patients with HNF1A-MODY. Retinal photographs, 12 for each patient, were done by a fundus camera. Signs of DR were graded according to the DR disease severity scale. Statistical tests were performed to assess differences between the groups and logistic regression was done for the association with DR.The mean age at examination was 34.5±14.8 and 39.9±15.2 in the GCK-MODY and HNF1A-MODY groups, respectively. Mild nonproliferative DR (NPDR) was found in one patient with the GCK mutation and likely concomitant type 1 diabetes, whereas DR was diagnosed in 15 HNF1A-MODY patients: 9 with proliferative, 3 with moderate NPDR and 2 with mild NPDR. In univariate logistic regression analysis in the HNF1A-MODY group, significant results were found for diabetes duration, fasting glycemia, HbA1c, arterial hypertension, age at the examination, and eGFR. The strongest independent predictors of DR in HNF1A-MODY were markers of glucose control: HbA1c (OR: 2.05, CL%95: 1.2-3.83, p=0.01) and glucose (p=0.006, OR: 1.40, CL%95: 1.12-1.83) analyzed in 2 separated models. Additionally, arterial hypertension independently predicted DR (OR: 9.06, CL%95: 1.19-98.99, p=0.04) in the model with HbA1c as glycaemic control marker.In conclusion, DR of any degree was not present in our GCK-MODY group, while in spite of young age almost every fourth subject with HNF1A-MODY showed signs of this complication.

FAMILIARITY TRANSFER AS AN EXPLANATION OF THE DÉJÀ VU EFFECT.

Déjà vu is often explained in terms of an unconscious transfer of familiarity between a familiar object or objects and accompanying new objects. However, empirical research tests more the priming effectiveness than such a transfer. This paper reviews the main explanations of déjà vu, proposes a cognitive model of the phenomenon, and tests its six major assumptions. The model states that a sense of familiarity can be felt toward an objectively new stimulus (point 1) and that it can be transferred from a known stimulus to a novel one (point 2) in a situation where the person is unaware of such a transfer (point 3). The criteria for déjà vu are that the known and the novel stimuli may have graphical or semantic similarity, but differences exclude priming explanations (point 4); the familiarity measure should be of an non-rational nature (sense of familiarity rather than recognition; point 5); and that the feeling of familiarity toward a novel stimuli produces a conflict, which could be measured by means of increased reaction (point 6). 119 participants were tested in three experiments. The participants were to assess the novel stimuli in terms of their sense of familiarity. The novel stimuli were primed or were not primed by the known stimulus (Exp. 1) or primed by the known vs a novel stimulus (Exp. 2 and 3). The priming was subliminal in all the experiments. Reaction times were measured in Exps. 2 and 3. The participants assessed the novel stimuli as more familiar when they were preceded by a known stimulus than when they were not (Exp. 1) or when they were preceded by a novel stimulus (Exps. 2 and 3). Reaction times were longer for assessments preceded by known stimulus than for assessments preceded by a novel stimulus, which contradicts the priming explanations. The results seem to support all six points of the proposed model of the mechanisms underlying the déjà vu experience.

Induced pluripotent stem cells as a model for diabetes investigation.

Mouse and human induced pluripotent stem cells (iPSCs) may represent a novel approach for modeling diabetes. Taking this into consideration, the aim of this study was to generate and evaluate differentiation potential of iPSCs from lep(db/db) (db/db) mice, the model of diabetes type 2 as well as from patients with Maturity Onset Diabetes of the Young 3 (HNF1A MODY). Murine iPSC colonies from both wild type and db/db mice were positive for markers of pluripotency: Oct3/4A, Nanog, SSEA1, CDy1 and alkaline phosphatase and differentiated in vitro and in vivo into cells originating from three germ layers. However, our results suggest impaired differentiation of db/db cells into endothelial progenitor-like cells expressing CD34 and Tie2 markers and their reduced angiogenic potential. Human control and HNF1A MODY reprogrammed cells also expressed pluripotency markers: OCT3/4A, SSEA4, TRA-1-60, TRA-1-81, formed embryoid bodies (EBs) and differentiated into cells of three germ layers. Additionally, insulin expressing cells were obtained from those partially reprogrammed cells with direct as well as EB-mediated differentiation method. Our findings indicate that disease-specific iPSCs may help to better understand the mechanisms responsible for defective insulin production or vascular dysfunction upon differentiation toward cell types affected by diabetes.

A comparison of biphasic insulin aspart and insulin glargine administered with oral antidiabetic drugs in type 2 diabetes mellitus--a systematic review and meta-analysis.

OBJECTIVE: It is uncertain whether the addition of biphasic insulin analogues to oral antidiabetic drugs (OADs) is as effective and safe as basal insulin in patients with type 2 diabetes mellitus (T2DM). We performed a systematic review to compare glycaemic control and selected clinical outcomes in T2DM patients inadequately controlled with OADs whose treatment was intensified by adding biphasic insulin aspart (BIAsp 30) or insulin glargine (IGlar). METHODS: The analysis included randomised controlled trials (RCTs) identified by a systematic literature search in medical databases (MEDLINE, EMBASE, The Cochrane Library and other sources) up to March 2013. Studies met the inclusion criteria if they compared BIAsp 30 vs. IGlar added to at least one OAD in T2DM patients. Trials applying different OADs in both treatment arms were also included. Results were presented as weighted mean difference (WMD) or odds ratio (OR) with a 95% confidence interval (CI). RESULTS: Five trials, including a total number of 1758 patients followed up from 24 to 28 weeks, were identified. Quantitative synthesis demonstrated that BIAsp 30 reduced HbA1c level more efficiently than IGlar [5 RCTs; WMD (95% CI): -0.21% (-0.35%, -0.08%)]. Differences were observed in favour of BIAsp for lower mean prandial glucose increment [3 RCTs; WMD (95% CI): -14.70 mg/dl (-20.09, -9.31)]; no difference was observed for fasting plasma glucose [3 RCTs; WMD (95% CI): 7.09 mg/dl (-15.76, 29.94)]. We found no evidence for higher risk of overall [2 RCTs; 63% vs. 51%; OR = 1.77 (0.91; 3.44)] and severe hypoglycaemic episodes [4 RCTs; 0.98% vs. 1.12%; OR (95% CI) = 0.88 (0.31, 2.53)] in the BIAsp 30 group as compared with IGlar group. Twice-daily administration of BIAsp 30 resulted in larger weight gain [2 RCTs; WMD (95% CI) = 1.78 kg (1.04; 2.52)]. CONCLUSIONS: BIAsp 30 added to OAD therapy results in a better glycaemic control as compared with IGlar in T2DM patients. BIAsp 30 use is associated with slightly larger weight gain but no rise in risk of severe hypoglycaemic episodes.

Bacterial adaptation to cold.

Micro-organisms react to a rapid temperature downshift by triggering a physiological response to ensure survival in unfavourable conditions. Adaptation includes changes in membrane composition and in the translation and transcription machineries. The cold shock response leads to a growth block and overall repression of translation; however, there is the induction of a set of specific proteins that help to tune cell metabolism and readjust it to the new conditions. For a mesophile like E. coli, the adaptation process takes about 4 h. Although the bacterial cold shock response was discovered over two decades ago we are still far from understanding this process. In this review, we aim to describe current knowledge, focusing on the functions of RNA-interacting proteins and RNases involved in cold shock adaptation.

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.

Apolipoprotein M can discriminate HNF1A-MODY from Type 1 diabetes.

AIMS: Missed diagnosis of maturity-onset diabetes of the young (MODY) has led to an interest in biomarkers that enable efficient prioritization of patients for definitive molecular testing. Apolipoprotein M (apoM) was suggested as a biomarker for hepatocyte nuclear factor 1 alpha (HNF1A)-MODY because of its reduced expression in Hnf1a(-/-) mice. However, subsequent human studies examining apoM as a biomarker have yielded conflicting results. We aimed to evaluate apoM as a biomarker for HNF1A-MODY using a highly specific and sensitive ELISA. METHODS: ApoM concentration was measured in subjects with HNF1A-MODY (n = 69), Type 1 diabetes (n = 50), Type 2 diabetes (n = 120) and healthy control subjects (n = 100). The discriminative accuracy of apoM and of the apoM/HDL ratio for diabetes aetiology was evaluated. RESULTS: Mean (standard deviation) serum apoM concentration (µmol/l) was significantly lower for subjects with HNF1A-MODY [0.86 (0.29)], than for those with Type 1 diabetes [1.37 (0.26), P = 3.1 × 10(-18) ) and control subjects [1.34 (0.22), P = 7.2 × 10(-19) ). There was no significant difference in apoM concentration between subjects with HNF1A-MODY and Type 2 diabetes [0.89 (0.28), P = 0.13]. The C-statistic measure of discriminative accuracy for apoM was 0.91 for HNF1A-MODY vs. Type 1 diabetes, indicating high discriminative accuracy. The apoM/HDL ratio was significantly lower in HNF1A-MODY than other study groups. However, this ratio did not perform well in discriminating HNF1A-MODY from either Type 1 diabetes (C-statistic = 0.79) or Type 2 diabetes (C-statistic = 0.68). CONCLUSIONS: We confirm an earlier report that serum apoM levels are lower in HNF1A-MODY than in controls. Serum apoM provides good discrimination between HNF1A-MODY and Type 1 diabetes and warrants further investigation for clinical utility in diabetes diagnostics.

Prevalence of monogenic diabetes amongst Polish children after a nationwide genetic screening campaign.

AIMS/HYPOTHESIS: The aim of this study was to study dynamic changes in the prevalence of different types of diabetes in paediatric populations in Poland, with a specific focus on monogenic diabetes (MD). METHODS: Using epidemiologic data (PolPeDiab Collaboration) and nationwide genetic test results (TEAM Programme), we compared the prevalence of type 1, type 2 and cystic fibrosis-related diabetes (CFRD) and MD. Genetically confirmed MD included MODY, neonatal diabetes and Wolfram and Alström syndromes. The study covered all children aged 0-18 years treated for diabetes between 2005 and 2011 in three regions, inhabited by 23.7% (1,989,988) of Polish children, with a low prevalence of childhood obesity (<5%). RESULTS: The prevalence of type 1 diabetes showed a continuous increase, from 96 to 138/100,000 children. The prevalence of type 2 diabetes and CFRD also increased, from 0.3 to 1.01/100,000 children and from 0.1 to 0.95/100,000 children, respectively. The prevalence of MD was stable at between 4.2 and 4.6/100,000 children, accounting for 3.1-4.2% of children with diabetes, with glucokinase (GCK)-MODY being the most frequent type, amounting to 83% of patients with MD. The percentage of positive test results decreased with the number of referrals, suggesting that children with the highest probability of MD were referred initially, followed by those with a less clear-cut phenotype. The prevalence of neonatal diabetes equalled 1 in 300,000 children. CONCLUSIONS/INTERPRETATION: The prevalence of MD in a paediatric population with a low prevalence of obesity remains stable and is nearly fivefold higher than that of type 2 diabetes and CFRD, justifying a need for increased access to genetic diagnostic procedures in diabetic children.

Impact of FTO genotypes on BMI and weight in polycystic ovary syndrome: a systematic review and meta-analysis.

AIMS/HYPOTHESIS: FTO gene single nucleotide polymorphisms (SNPs) have been shown to be associated with obesity-related traits and type 2 diabetes. Several small studies have suggested a greater than expected effect of the FTO rs9939609 SNP on weight in polycystic ovary syndrome (PCOS). We therefore aimed to examine the impact of FTO genotype on BMI and weight in PCOS. METHODS: A systematic search of medical databases (PubMed, EMBASE and Cochrane CENTRAL) was conducted up to the end of April 2011. Seven studies describing eight distinct PCOS cohorts were retrieved; seven were genotyped for SNP rs9939609 and one for SNP rs1421085. The per allele effect on BMI and body weight increase was calculated and subjected to meta-analysis. RESULTS: A total of 2,548 women with PCOS were included in the study; 762 were TT homozygotes, 1,253 had an AT/CT genotype, and 533 were AA/CC homozygotes. Each additional copy of the effect allele (A/C) increased the BMI by a mean of 0.19 z score units (95% CI 0.13, 0.24; p = 2.26 × 10(-11)) and body weight by a mean of 0.20 z score units (95% CI 0.14, 0.26; p = 1.02 × 10(-10)). This translated into an approximately 3.3 kg/m(2) increase in BMI and an approximately 9.6 kg gain in body weight between TT and AA/CC homozygotes. The association between FTO genotypes and BMI was stronger in the cohorts with PCOS than in the general female populations from large genome-wide association studies. Deviation from an additive genetic model was observed in heavier populations. CONCLUSIONS/INTERPRETATION: The effect of FTO SNPs on obesity-related traits in PCOS seems to be more than two times greater than the effect found in large population-based studies. This suggests an interaction between FTO and the metabolic context or polygenic background of PCOS.

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.

HbA1c-based diabetes diagnosis among patients with glucokinase mutation (GCK-MODY) is affected by a genetic variant of glucose-6-phosphatase (G6PC2).

AIMS: Genetic variation at the rs560887 locus of the glucose-6-phosphatase, catalytic 2 gene (G6PC2) is known to affect regulation of fasting glycaemia. We determined the rs560887 genotype of patients with monogenic diabetes and glucokinase gene mutations (GCK-MODY) and correlated the genotypes with HbA(1c) levels. METHODS: Patients from families with GCK-MODY were recruited from two large cohorts from Poland (n = 128) and the Czech Republic (n = 154). Genotypes at the rs560887 polymorphic site in G6PC2 were examined using real-time quantitative polymerase chain reaction. The effect of rs560887 genotype on age at diagnosis of GCK-MODY and initial HbA(1c) levels were evaluated separately within both cohorts. Following that, a meta-analysis of rs560887 genotype-HbA(1c) associations of both Polish and Czech cohorts was performed to confirm homogeneity of findings and validate cohort-specific results. RESULTS: GG homozygosity at rs560887 was associated with marginally elevated HbA(1c) levels (P = 0.07 in both cohorts). The effects observed in both groups were very homogeneous (Q = 0.18; P = 0.68). Meta-analysis showed that GG homozygosity at rs560887 was associated with mean HbA(1c) levels higher by 2.4 mmol/mol (0.24%), 95% CI 0.5-4.4 mmol/mol (0.05-0.44%) than in individuals with other genotypes. Additionally, meta-analysis of both cohorts showed that GG homozygous individuals had higher odds of reaching the 48 mmol/mol (6.5%) diagnostic threshold of diabetes; (odds ratio 1.90; 95% CI 1.07-3.36; P = 0.03). No such effects were observed for age at diagnosis of diabetes. CONCLUSIONS: Variation at the rs560887 locus of G6PC2 is associated with worse glycated haemoglobin levels in individuals with GCK mutations; GG homozygotes are more likely to meet diagnostic criteria for diabetes based on HbA(1c) level.

Novel glucokinase mutations in patients with monogenic diabetes - clinical outline of GCK-MD and potential for founder effect in Slavic population.

Glucokinase (GCK) gene mutations are the causative factor of GCK-MD (monogenic diabetes) characterized by a mild clinical phenotype and potential for insulin withdrawal. This study presents the results of a nationwide genetic screening for GCK-MD performed in Poland. A group of 194 patients with clinical suspicion of GCK-MD and 17 patients with neonatal diabetes were subjected to GCK sequencing. Patients negative for GCK mutations were subjected to multiplex ligation-dependent probe amplification (MLPA) to detect deletions or insertions. A total of 44 GCK heterozygous mutations were found in 68 probands (35%). Among those, 20 mutations were novel ones: A282fs, D198V, E158X, G246V, G249R, I348N, L165V, L315Q, M115I, N254S, P284fs, Q338P, R377L, R43C, R46S, S212fs, S212P, T255N, V406A and Y214D. No abnormalities were detected in MLPA analysis. Homozygous D278E mutation was found in one patient with neonatal diabetes. The most frequently observed combinations of symptoms typical for GCK-MD were mild diabetes and/or fasting hyperglycaemia (98.3%), positive C-peptide at diagnosis (76%) and dominant mode of inheritance (59%). This study outlines numerous novel mutations of the GCK gene present in white Caucasians of Slavic origin. Thorough clinical assessment of known factors associated with GCK-MD may facilitate patient selection.

Aronia melanocarpa fruit extract exhibits anti-inflammatory activity in human aortic endothelial cells.

BACKGROUND: Altered expression of cell adhesion molecules (CAMs) has been implicated in a variety of chronic inflammatory conditions, including atherosclerosis. Regulation of adhesion molecule expression by specific redox-sensitive mechanisms has been reported. Additionally, it has been observed that the extract of Aronia melanocarpa (A. Melanocarpa) fruits, rich in polyphenols, exhibits potent anti-oxidant properties and displays cardioprotective activity. METHODS AND RESULTS: Human aortic endothelial cells (HAECs) were pretreated with various concentrations (primarily 50 µg/mL) of Aronia Melanocarpa fruit extract prior to treatment with TNFα (10 ng/mL) for various periods of time. The surface protein and mRNA expression of ICAM-1 and VCAM-1 were determined using flow cytometry and real-time RT-PCR, respectively. Adhesion of peripheral blood mononuclear leucocytes (PBMLs) to TNFα-treated HAECs was evaluated by an adhesion assay. Activation of NF-κB was evaluated by measuring NF-κB p65 phosphorylation using flow cytometry. ROS production was determined by reduction in fluorescent 2',7'-dichlorofluorescein diacetate (DCFH-DA). Tested A. Melanocarpa extract significantly inhibited the expression of ICAM-1 and VCAM-1, attenuated the phosphorylation of NF-κB p65 and decreased intracellular ROS production in TNFα-treated HAECs. CONCLUSION: We conclude that A. Melanocarpa fruit extract exhibits anti-inflammatory effects in HAECs by inhibiting the expression of endothelial CAMs, activation of NF-κB and production of ROS.