N-glycosylation of immunoglobulin A in children and adults with type 1 diabetes mellitus.

Aims: To identify N-glycan structures on immunoglobulin A related to type 1 diabetes mellitus among children at the disease onset and adults with type 1 diabetes mellitus. Methods: Human polyclonal IgA N-glycans were profiled using hydrophilic interaction ultra performance liquid chromatography in two cohorts. The first cohort consisted of 62 children at the onset of type 1 diabetes mellitus and 86 of their healthy siblings. The second cohort contained 84 adults with the disease and 84 controls. Associations between N-glycans and type 1 diabetes mellitus were tested using linear mixed model for the paediatric cohort, or general linear model for the adult cohort. False discovery rate was controlled by Benjamini-Hochberg method modified by Li and Ji. Results: In children, an increase in a single oligomannose N-glycan was associated with type 1 diabetes mellitus (B = 0.529, p = 0.0067). N-glycome of the adults displayed increased branching (B = 0.466, p = 0.0052), trigalactosylation (B = 0.466, p = 0.0052), trisialylation (B = 0.629, p < 0.001), and mannosylation (B = 0.604, p < 0.001). The strongest association with the disease was a decrease in immunoglobulin A core fucosylation (B = -0.900, p < 0.001). Conclusions: Changes in immunoglobulin N-glycosylation patterns in type 1 diabetes point to disruptions in immunoglobulin A catabolism and dysregulated inflammatory capabilities of the antibody, potentially impacting immune responses and inflammation.

Fragility spinal fractures among cirrhotic liver transplant candidates in Croatia.

INTRODUCTION: Existing data on fragility spinal fractures prevalence in liver transplant candidates are scarce and inconsistent. This may be due to other comorbidities, besides hepatic osteodystrophy (HO), that contribute to bone loss and fragility fracture prevalence in chronic liver disease (CLD). OBJECTIVES: The aim of this study was to investigate the prevalence of spinal thoracic and lumbar fragility fractures among cirrhotic, non-chronic kidney disease (CKD), non-diabetic liver transplant candidates and to explore their relationship with clinical characteristics, laboratory markers and dual-energy x-ray absorptiometry (DXA) results. MATERIAL AND METHODS: This cross-sectional observational study was conducted at Merkur University Hospital, Croatia, between February 2019 and May 2023. Adult patients with liver cirrhosis referred for liver transplantation were included. Patients with acute infection, CKD, diabetes mellitus, malignancies, inflammatory bone diseases and those on corticosteroid or antiresorptive therapy were excluded. Clinical, laboratory and radiological assessment was carried out and patients were accordingly allocated into non-fractured and fractured group for the purpose of statistical analysis. RESULTS: A total of 90 patients were included in the study. There was 123 fractures, 87 (70.7 %) in the thoracic and 36 (29.3 %) in the lumbar region. Eighty-nine (72.4 %) fractures were grade 1, 31 (25.2 %) were grade 2 and 3 (2.4 %) were grade 3. Patients in the fractured group were significantly older (p < 0.001). No significant differences between fractured and non-fractured group according to laboratory and DXA parameters were noted. Subgroup with lumbar fractures had significantly lower bone mineral density values at L1-L4 region. Statistically significant negative correlation between bone specific alkaline phosphatase (BALP) and hip total BMD (rho = -0.414, p < 0.001) and spine total BMD (rho = -0.258, p = 0.014) values was found. CONCLUSION: Present study confirmed detrimental impact of CLD and HO on bone strength. DXA measurement correlated with the presence of lumbar fragility fractures. A combination of standard X-ray imaging and DXA is needed for adequate bone evaluation in pretransplant period and BALP could be useful for detecting HO in CLD. Searching for other risk factors and implementing bone turnover markers and additional imaging techniques for bone loss evaluation in liver transplant candidates is needed.

Fibroblast growth factor 23 and its role in bone diseases.

Fibroblast growth factor 23 (FGF23) has been casually linked to numerous hypophosphatemic bone diseases, however connection with bone loss or fragility fractures is still a matter of debate. The purpose of this review is to explore and summarise the known actions of FGF23 in various pathological bone conditions. Besides implication in bone mineralisation, elevated FGF23 showed a pathological effecton bone remodelling, primarily by inhibiting osteoblast function. Unlike the weak association with bone mineral density, high values of FGF23 have been connected with fragility fracture prevalence. This review shows that its effects on bone are concomitantly present on multiple levels, affecting both qualitative and quantitative part of bone strength, eventually leading to impaired bone strength and increased tendency of fractures. Recognising FGF23 as a risk factor for the development of bone diseases and correcting its levels could lead to the reduction of morbidity and mortality in specific groups of patients.

Relationship between ß-Cell Autoantibodies and Their Combination with Anthropometric and Metabolic Components and Microvascular Complications in Latent Autoimmune Diabetes in Adults.

AIMS: Our study aimed to investigate the relationship between three autoantibodies and their combination with anthropometric and metabolic components and microvascular complications in patients with latent autoimmune diabetes in adults (LADA). METHODS: Our study included 189 LADA patients divided into four subgroups according to the autoantibodies present: glutamic acid decarboxylase autoantibodies (GADA) only; zinc transporter-8 autoantibodies (ZnT8A)+GADA; insulinoma-associated-2 autoantibodies (IA-2)+GADA; and ZnT8+IA-2+GADA. RESULTS: Compared to GADA positivity only, patients with ZnT8+GADA positivity and ZnT8+IA-2+GADA positivity had a shorter diabetes duration and lower body mass index (BMI); patients with ZnT8+GADA positivity were younger and showed an increase in glomerular filtration rate, while those with ZnT8+IA-2+GADA positivity had lower C-peptide and lower insulin resistance measured with HOMA2-IR. In a multiple regression analysis, ZnT8 positivity was associated with lower BMI (p = 0.0024), female sex (p = 0.0005), and shorter duration of disease (p = 0.0034), while IA-2 positivity was associated with lower C-peptide levels (p = 0.0034) and shorter diabetes duration (p = 0.02). No association between antibody positivity and microvascular complications of diabetes, including retinopathy, neuropathy, and microalbuminuria, as well as with variables of glucose control and ß-cell function were found. CONCLUSION: The results of our study suggest that ZnT8 and IA-2 autoantibodies are present in a significant number of LADA patients and associated with clinical and metabolic characteristics resembling classic type 1 diabetes. Due to increased LADA prevalence, earlier identification of patients requiring frequent monitoring with the earlier intensification of insulin therapy might be of special clinical interest.

Diagnostic challenges of diabetic kidney disease.

Diabetic kidney disease (DKD) is one of the most common microvascular complications of both type 1 and type 2 diabetes and the most common cause of the end-stage renal disease (ESRD). It has been evidenced that targeted interventions at an early stage of DKD can efficiently prevent or delay the progression of kidney failure and improve patient outcomes. Therefore, regular screening for DKD has become one of the fundamental principles of diabetes care. Long-established biomarkers such as serum-creatinine-based estimates of glomerular filtration rate and albuminuria are currently the cornerstone of diagnosis and risk stratification in routine clinical practice. However, their immanent biological limitations and analytical variations may influence the clinical interpretation of the results. Recently proposed new predictive equations without the variable of race, together with the evidence on better accuracy of combined serum creatinine and cystatin C equations, and both race- and sex-free cystatin C-based equation, have enabled an improvement in the detection of DKD, but also require the harmonization of the recommended laboratory tests, wider availability of cystatin C testing and specific approach in various populations. Considering the complex pathophysiology of DKD, particularly in type 2 diabetes, a panel of biomarkers is needed to classify patients in terms of the rate of disease progression and/or response to specific interventions. With a personalized approach to diagnosis and treatment, in the future, it will be possible to respond to DKD better and enable improved outcomes for numerous patients worldwide.

Associations between plasma protein, IgG and IgA N-glycosylation and metabolic health markers in pregnancy and gestational diabetes.

BACKGROUND: Monitoring human circulating N-glycome could provide valuable insight into an individual's metabolic status. Therefore, we examined if aberrant carbohydrate metabolism in gestational diabetes mellitus (GDM) associates with alterations in plasma protein, immunoglobulin G (IgG) and immunoglobulin A (IgA) N-glycosylation. METHODS: Plasma protein, IgG and IgA N-glycans were enzymatically released, purified and chromatographically profiled in 48 pregnant women with normal glucose tolerance and 41 pregnant women with GDM, all sampled at 24-28 weeks of gestation. Linear mixed models adjusting for age and multiple testing (FDR<0.05) were used to investigate the associations between glycosylation features, metabolic markers and GDM status. RESULTS: Fasting insulin exhibited significant associations to numerous glycan traits, including plasma protein galactosylation, sialylation, branching, core fucosylation and bisection, to IgG core fucosylated, bisected (FA2B) and afucosylated disialylated (A2G2S2) glycan and to IgA trisialylated triantennary (A3G3S3) glycan (padj range: 4.37x10-05-4.94x10-02). Insulin resistance markers HOMA2-IR and HOMA2-%B were mostly associated to the same glycan structures as fasting insulin. Both markers showed positive association with high-branched plasma glycans (padj = 1.12x10-02 and 2.03x10-03) and negative association with low-branched plasma glycans (padj = 1.21x10-02 and 2.05x10-03). Additionally, HOMA2-%B index was significantly correlated with glycosylation features describing IgG sialylation. Multiple plasma protein IgG and IgA glycans showed significant associations with total cholesterol and triglyceride levels. None of the tested glycan traits showed a significant difference between GDM and normoglycemic pregnancies. CONCLUSION: Markers of glucose homeostasis and lipid metabolism in pregnancy show extensive associations to various N-glycosylation features. However, plasma protein, IgG and IgA N-glycans were not able to differentiate pregnant women with and without GDM, possibly due to numerous physiological changes accompanying pregnancy, which confound the impact of GDM on protein glycosylation.

N-glycosylation of serum proteins in adult type 1 diabetes mellitus exposes further changes compared to children at the disease onset.

OBJECTIVE: Previously we have shown that plasma protein N-glycosylation is changed in children at the onset of type 1 diabetes. In this study, we aim to identify N-glycan changes in adults with T1DM, compare them to those in children, and investigate their associations with disease duration, complications, glycaemic status, and smoking. METHODS: Serum protein N-glycans from 200 adults with type 1 diabetes and 298 healthy controls were analysed using ultra-high performance liquid chromatography and divided into 39 directly measured glycan groups from which 16 derived traits were calculated. RESULTS: Compared to healthy controls, subjects with type 1 diabetes showed differences in 19 glycan groups and a decrease in monogalactosylated, an increase in digalactosylated, monosialylated, and antennary fucosylated derived traits, from which changes in monogalactosylation and seven directly measured traits overlapped with previously reported in children. Changes in four directly measured and two derived traits previously seen in children were not detected in adults. HbA1c was positively associated with sialylated and highly branched structures, whereas N-glycome was not influenced by disease duration or diabetic complications. CONCLUSIONS: Our results suggest potential N-glycome involvement in different stages of type 1 diabetes, including processes underlying its development, the disease itself, as well as those occurring after disease establishment.

Inflammatory, oxidative and DNA damage status in vegetarians: is the future of human diet green?

The health benefit of a vegetarian diet is still under debate as it may result in a higher intake of some beneficial micronutrients, while others may be reduced, thus influencing various metabolic pathways and health-related biomarkers. This scoping review discusses inflammatory, oxidative and DNA damage status in vegetarians and vegans compared to omnivores. Most of the reviewed studies indicated favorable effects of a vegetarian diet on oxidative status compared to omnivores but did not clearly associate particular dietary habits to genome damage. The evidence on the effect of vegetarian diet on the inflammatory and immunological biomarkers is poor, which could at least partly be explained by methodological constraints such as small sample size, short duration of vegetarianism and inconsistent definitions of the omnivorous diet. The only inflammatory biomarker that seems to be associated with the vegetarian diet was inflammatory mediator C-reactive protein, which in several studies showed lower values in vegetarians as compared to omnivores. There were very few studies on immunological markers and the results on the difference between vegetarians and omnivores were inconclusive. Although several biomarkers involved in oxidative stress and inflammation showed a beneficial association with the vegetarian diet, further research in well-defined and sufficiently sized cohorts is needed to provide more evidence.

The Impact of Hypoglycemia and EPA and DHA Supplementation on Brain-Derived Neurotrophic Factor Level in Pregnant Women with Type 1 Diabetes: A Prospective Cohort Study.

BACKGROUND: In addition to its neuroprotective effect, Brain-derived neurotrophic factor (BDNF) also plays a role in glucose and lipid metabolism. This study aims: a) to find changes in the BDNF concentration during pregnancy in type 1 diabetes. b) to prove the effect of DHA and EPA supplementation on changes in BDNF concentrations c) to investigate the impact of hypoglycemia on BDNF concentration. SUBJECTS AND METHODS: The data from this study were from the PRE-HYPO cohort study. Twenty-one of them were on a standard diabetic diet enriched with EPA and DHA (EPA 120 mg/day and DHA 616 mg/day; Exposed group), and nineteen pregnant diabetic women were on the standard diabetic diet without EPA and DHA supplementation (Non-exposed group). In the first trimester of pregnancy, fifteen pregnant women developed hypoglycemia episodes (≤3.9 mmol/L; HYPO+ group), and twenty-five pregnant women did not have hypoglycemia episodes (HYPO- group). RESULTS: BDNF concentration significantly decreased during pregnancy from the first to the third trimester, in Non-exposed from 25.1 (22.0-30.2) to 22.1 (16.3-28.2), P<0.05, in the Exposed group from 22.1 (19.8-25.9) to 18.1 (14.8-18.9), P<0.01. Pregnant patients with hypoglycemia episodes (HYPO+ subgroup) had significantly higher BDNF in the third trimester of pregnancy [22.5 (20.6-28.4)] when compared with patients who did not develop hypoglycemia [16.3 (14.3-18.8), P<0.001]. In the third trimester of pregnancy, BDNF and n-6 PUFAs were associated with hypoglycemia (OR 1.818 95 % CI 1.079-3.003, P=0.025; OR 1.103 95 % CI 1.001-1.217, P=0.048). Total F.A.s were inversely associated with hypoglycemia (OR 0.969 95% CI 0.939-0.998, P=0.048). CONCLUSION: Pregnant women with hypoglycemia (HYPO+ group) had higher concentrations of BDNF in the first and third trimesters of pregnancy compared to those without hypoglycemia. An increase in body weight during pregnancy leads to a decrease in BDNF concentration.

Sex-specific effects of vegetarian diet on adiponectin levels and insulin sensitivity in healthy non-obese individuals.

OBJECTIVES: The beneficial influence of a vegetarian diet in reducing the risk for metabolic syndrome has been demonstrated. However, adiponectin production and secretion are scarcely studied in vegetarians, despite their important role in recovering metabolic homeostasis by reducing visceral obesity, inflammation, and insulin resistance. The aim of this study was to evaluate the effect of a vegetarian diet on serum adiponectin levels and its association with the established biomarkers of insulin sensitivity and inflammation in healthy, non-obese individuals. METHODS: Adiponectin, C-reactive protein, uric acid, glucose, insulin, lymphocyte and polymorphonuclear cell counts were determined in the blood of sex- and age-matched healthy vegetarian (n = 40) and omnivore (n = 36) individuals. The homeostatic model assessment (HOMA-2) calculator was used for the ß-cell function (HOMA2-%B) and insulin resistance index (HOMA2-IRI) estimation. RESULTS: Adiponectin levels were significantly higher in female vegetarians than the respective omnivore controls (P = 0.03), whereas no dietary-associated difference was observed in men. HOMA2-%B was significantly higher in vegetarians than in omnivore controls (P = 0.04), whereas no diet-dependent differences were found in insulin, HOMA2-IRI, inflammatory, and metabolic biomarkers. Multiple regression analysis showed that adiponectin levels were significantly predicted by the type of diet only in women (P = 0.042), whereas no associations were found in men. CONCLUSIONS: A vegetarian diet resulted in improved ß-cell function. Favorable adiponectin and insulin sensitivity responses in women reveal a distinct effect of diet-to-metabolic homeostasis, indicating an interesting pattern of sexual dimorphism regarding the beneficial metabolic effect of a vegetarian diet.

Association between arsenic exposure and biomarkers of type 2 diabetes mellitus in a Croatian population: A comparative observational pilot study.

Chronic exposure to high inorganic As levels in drinking water has been related to many diseases, including type 2 diabetes mellitus (T2D). The association with low and moderate As levels, however, remains controversial and has yet not been studied in European populations. This study aimed to investigate possible association between As exposure and biomarkers of T2D in Croatian population. Observation recruited 86 adults from Eastern Croatia, where groundwater is contaminated with inorganic As, and 116 adults from Western Croatia, where As levels in drinking water are low. Both populations were divided in patient groups (T2D or prediabetes) and healthy controls. Exposure was assessed by determining total As in blood and urine and As metabolites in urine. Eastern Croatian population had a significantly higher content of As in urine than Western, whereas the opposite was true for arsenobetain. Total As and As metabolites in urine positively correlated with hemoglobin A1c (HbA1c) and negatively with albuminuria. This study provides important preliminary data on the levels of As in urine and blood and their association with biomarkers of T2D in Croatian population exposed to low or moderate levels of As through drinking water as a solid basis for further research of the pathophysiological effects of such As exposure on the status and complications of diabetes.

Leptin as a Key Player in Insulin Resistance of Liver Cirrhosis? A Cross-Sectional Study in Liver Transplant Candidates.

Insulin resistance is associated with increased risk of death and liver transplantation in the cirrhotic population, independent of disease aetiology. However, factors accounting for insulin resistance in the context of cirrhosis are incompletely understood. This study aimed to investigate the association between adiponectin and leptin with insulin resistance in cirrhotic patients and to assess the influence of disease severity on insulin resistance and metabolic status. This cross-sectional study included 126 non-diabetic cirrhotic transplant candidates. The homeostasis model assessment 2 model was used to determine the insulin resistance index, and fasting adiponectin, leptin, insulin, c-peptide, glucose, HbA1c, and lipid profiles were analysed. Insulin resistance was detected in 83% of subjects and associated with increased leptin, fasting plasma glucose and body mass index, and lower triglyceride levels. Logistic regression analysis identified leptin and triglycerides as independent predictors of insulin resistance (OR 1.247, 95% CI 1.076-1.447, p = 0.003; OR 0.357, 95% CI 0.137-0.917, p = 0.032.). Leptin levels remained unchanged, whereas adiponectin levels increased (p < 0.001) with disease progression, and inversely correlated with HbA1c (ρ = -0.349, p < 0.001). Our results indicate that leptin resistance, as indicated by elevated leptin levels, can be regarded as a contributing factor to insulin resistance in cirrhotic patients, whereas triglycerides elicited a weak protective effect. Progressively increasing adiponectin levels elicited a positive effect on glucose homeostasis, but not insulin sensitivity across disease stages.

Preserved C-peptide secretion in patients with type 1 diabetes and incipient chronic complications is associated with lower serum resistin and higher uric acid levels.

BACKGROUND AND AIMS: Previous studies suggested that long-term perseverance of beta-cell function in patients with type 1 diabetes (T1DM) is associated with lower incidence of microvascular complications. The objective of this study was to evaluate preserved C-peptide secretion in patients with T1DM without overt chronic complications and to explore associations with resistin and uric acid as biomarkers of microvascular complication pathogenesis. MATERIALS AND METHODS: We assessed residual beta-cell function in 164 T1DM patients (male/female = 91/73; age/diabetes duration range = 18-70/1-30 years) using an ultrasensitive C-peptide ELISA assay with detection limit of 2.5 pmol/L and total coefficient of variation (CV) 5,8% (Mercodia, Sweden). Serum level of uric acid was measured by enzymatic method (AU680, Beckman Coulter, USA) while resistin concentration was determined by the ELISA assay (Biovendor, Czech Republic). RESULTS: C-peptide secretors had shorter diabetes duration (5.1 vs. 16 years; p < 0,001), lower resistin (4.53 vs. 4.93 mg/mL p = 0.045), and higher uric acid (259 vs 238 µmol/L, p = 0.048) level than T1DM patients with no detectable C-peptide levels, while no differences in routine anthropometric and laboratory variables, including HbA1c, were observed. Although the proportion of C-peptide secretors significantly decreased across categories of diabetes duration (70%, 38%, 17% and 15% for <5, 5-10, 10-20 and 20-30 years of duration, respectively; p < 0,001), detectable C-peptide was found in 5/23 T1DM patients who were diagnosed with T1DM more than 20 years ago. CONCLUSION: The results of our study revealed that patients with detectable C-peptide had lower resistin and higher uric acid level compared to patients with undetectable C-peptide.

Alkaline comet assay results on fresh and one-year frozen whole blood in small volume without cryo-protection in a group of people with different health status.

Using alkaline comet assay, DNA damage tail length (TL) and tail intensity (TI) parameters were compared between fresh whole blood and 1-year frozen small volume whole blood in EDTA at -80 °C without cryo-preservation. The studied group consisted of 25 volunteers with different health conditions who served as their own controls for frozen blood results. Without the purification step after thawing, the results and the usefulness of this protocol for future/retrospective (including re-analysations of putative outliers) studies were analysed. Medical surveillance and blood sampling were done at Merkur University Hospital Zagreb. No significant differences between fresh and frozen blood samples in terms of the mean TL values (mean ± SD: 29.03 ± 12.26 vs. 25.36 ± 6.97, respectively) and the mean TI values (9.19 ± 10.37 vs. 10.17 ± 8.55, respectively), and highly damaged cell percentage were determined among 25 volunteers. Median TI frozen samples values of entire group were within the allowed 10-11% (8.24). At the individual levels, no correlation between fresh and frozen whole blood samples was observed in 11 volunteers who suffered from diabetes mellitus type 2. Strong correlation between fresh/frozen samples was seen for TL (r = 0.64, p < 0.015) and TI (r = 0.71, p < 0.005) in nondiabetic subgroup. Overall, the results demonstrated the usefulness of the 1-year frozen blood without induction of heavily damaged DNA. Due to the different DNA damage behaviour connected with different health conditions, future studies should involve more volunteers, oxidative DNA damage comet assay measurements, the inclusion of a washing step after thawing and inclusion of disease/antioxidant biomarkers.

Serum adipocytokines are associated with microalbuminuria in patients with type 1 diabetes and incipient chronic complications.

AIMS: Recent studies have implicated possible contribution of adipocytokines in development and progression of microvascular complications in patients with type 1 diabetes (T1DM). The aim of our study was to investigate relationship between adipocytokines, namely leptin, resistin, adiponectin and dipeptidyl peptidase-4 (DPP-4) activity, with albuminuria in T1DM. METHODS: This study included 202 T1DM without or with incipient microvascular complications. Urinary albumin excretion rate (UAE) was measured from at least two 24-h urine samples. Serum DPP-4 activity was measured by a colorimetric assay, and the level of adiponectin, leptin, and resistin was determined by the ELISA method. RESULTS: Serum DPP-4 activity and adiponectin were significantly higher in patients with normoalbuminuria compared to patients with microalbuminuria (47 vs 36 U/L, and 10.9 vs 7.3 µg/mL, respectively, p ≤ 0.02). In multivariate logistic regression analysis adiponectin and serum DPP-4 activity were significantly associated with risk of microalbuminuria in our subjects (p ≤ 0.04), with odds ratios of 0.72-0.99. However, after adjustment for age, sex, HbA1c, duration of diabetes and BMI, only serum DPP-4 activity was significantly associated with risk of microalbuminuria (p = 0.008). CONCLUSION: The results of our study suggest that serum DPP-4 activity is lower in T1DM with microalbuminuria. Prospective studies are warranted to evaluate the relationship between serum DPP-4 activity and progression and development of albuminuria and nephropathy in T1DM.

Plasma Fucosylated Glycans and C-Reactive Protein as Biomarkers of HNF1A-MODY in Young Adult-Onset Nonautoimmune Diabetes.

OBJECTIVE: Maturity-onset diabetes of the young (MODY) due to variants in HNF1A is the most common type of monogenic diabetes. Frequent misdiagnosis results in missed opportunity to use sulfonylureas as first-line treatment. A nongenetic biomarker could improve selection of subjects for genetic testing and increase diagnosis rates. We previously reported that plasma levels of antennary fucosylated N-glycans and high-sensitivity C-reactive protein (hs-CRP) are reduced in individuals with HNF1A-MODY. In this study, we examined the potential use of N-glycans and hs-CRP in discriminating individuals with damaging HNF1A alleles from those without HNF1A variants in an unselected population of young adults with nonautoimmune diabetes. RESEARCH DESIGN AND METHODS: We analyzed the plasma N-glycan profile, measured hs-CRP, and sequenced HNF1A in 989 individuals with diabetes diagnosed when younger than age 45, persistent endogenous insulin production, and absence of pancreatic autoimmunity. Systematic assessment of rare HNF1A variants was performed. RESULTS: We identified 29 individuals harboring 25 rare HNF1A alleles, of which 3 were novel, and 12 (in 16 probands) were considered pathogenic. Antennary fucosylated N-glycans and hs-CRP were able to differentiate subjects with damaging HNF1A alleles from those without rare HNF1A alleles. Glycan GP30 had a receiver operating characteristic curve area under the curve (AUC) of 0.90 (88% sensitivity, 80% specificity, cutoff 0.70%), whereas hs-CRP had an AUC of 0.83 (88% sensitivity, 69% specificity, cutoff 0.81 mg/L). CONCLUSIONS: Half of rare HNF1A sequence variants do not cause MODY. N-glycan profile and hs-CRP could both be used as tools, alone or as adjuncts to existing pathways, for identifying individuals at high risk of carrying a damaging HNF1A allele.

Analytical verification and quality assessment of the Tosoh HLC-723GX HbA1c analyzer.

OBJECTIVES: Ion-exchange high-performance liquid chromatography (IE-HPLC) has long been used as a reproducible and versatile analytical tool for HbA1c measurement. In this study, we performed analytical verification and quality assessment of the recently introduced small IE-HPLC Tosoh HLC-723GX HbA1c analyzer, and a comparison of results to immunoassay (IA) and capillary electrophoresis (CE). DESIGN AND METHODS: The total imprecision of Tosoh HLC-723GX was verified according to CLSI EP15-A2 protocol using commercial control materials (C-QC) and pooled human whole blood samples (HWB). The Sigma metric was used for the evaluation of quality targets. HbA1c results were compared to automated CE (MiniCap Flex Piercing, Sebia, France) and IA (Tina-quant HbA1c Gen 2, Cobas Integra 400+, Roche Diagnostics, USA) procedures. RESULTS: The total imprecision of Tosoh HLC-723GX-HbA1c for IFCC(mmol/mol) and NGSP(%) units was: 1.91/1.25% (HbA1c=31 mmol/mol/5.0%) and 0.51/0.63% (HbA1c=84 mmol/mol/9.8%) for C-QC, and 0.39/0.2% (HbA1c=47 mmol/mol/6.5%) and 0.77/0.46% (HbA1c=94 mmol/mol/10.8%) in HWB samples, respectively. Bland-Altman analysis did not reveal any deviation of the results between Tosoh HLC-723GX and CE: mean difference 0.0% (95%CI: -0.02927 to 0.02653%), while the mean HbA1c difference against IA was -0.07% (95%CI: -0.1039 to -0.02765). At the selected HbA1c clinical decision level (48 mmol/mol/6,5%), six sigma analysis gave σ value of 3.91, within a desirable classification of performance. CONCLUSION: The analytical performance of the Tosoh HLC-723GX complies with the rigorous quality criteria for clinical use of HbA1c, with the results comparable to the CE procedure. Tosoh HLC-723GX provides a plausible analytical choice for reliable HbA1c measurement in low-volume laboratories.

Age-dependent systemic DNA damage in early Type 2 Diabetes mellitus.

Oxidative stress, capable of eliciting damage to various biomolecules including DNA, is a recognized component of diabetes mellitus and its complications. Metabolic syndrome (MetS) is associated with the development of type 2 diabetes mellitus (T2DM), as well as other unfavorable outcomes. The aim of this study was to elucidate the role of oxidative stress in the development of T2DM, by investigating association of oxidative DNA damage with metabolic parameters in subjects with MetS and early T2DM. Selected anthropometric and biochemical parameters of MetS, inflammation and oxidative DNA damage: body mass index (BMI), fatty liver index (FLI), waist circumference (WC), total cholesterol, HDL and LDL-cholesterol, gamma-glutamyl transpeptidase (GGT), uric acid, C-reactive protein (CRP), total leukocyte/neutrophil count, and urinary 8-hidroxy-deoxyguanosine (u-8-OHdG) were assessed in male subjects with MetS and both younger (≤55 years) and older (>55 years) subjects with T2DM of short duration without complications. BMI, FLI, WC, total and LDL-cholesterol and uric acid were higher, while the u-8-OHdG was lower in MetS group, when compared to older T2DM subjects. None of these parameters were different neither between MetS and younger T2DM, nor between two sub-groups of subjects with T2DM. Values of CRP, HDL-cholesterol, triglycerides, GGT, leukocytes and neutrophils were not different between all examined groups of subjects. Higher 8-OHdG in older subjects with T2DM suggests that both aging process and diabetes could contribute to the development of DNA damage. Oxidative DNA damage cannot serve as an universal early marker of T2DM.