Anna Zielinska

The expression of genes involved in NF-κB activation in peripheral blood mononuclear cells of patients with gestational diabetes

OBJECTIVE In patients with obesity and type 2 diabetes, the changes in insulin resistance are associated with the changes in expression of genes involved in nuclear factor-κB (NF-κB) activation in peripheral blood mononuclear cells (PBMCs). As such studies have never been carried out in patients with gestational diabetes (GDM), in this study, we evaluated the expression of genes involved in NF-κB activation and related to glucose metabolism in PBMCs obtained from pregnant women with GDM and normal glucose tolerance (NGT). DESIGN AND METHODS RT-PCR was performed in 60 pregnant women divided into three groups: GDM at the 1st visit, i.e. in the 24th-28th weeks of gestation (GDM1), NGT at the first visit and GDM in the 29th-32nd weeks (GDM2), and NGT at both visits. The tests were repeated 3 months postpartum. RESULTS The GDM1 group had significantly higher TLR2 (P=0.024), TLR4 (P=0.037), STAT1 (P=0.027), and CX3CL1 (P=0.017) mRNA expression, whereas the GDM2 group showed markedly lower TNFRSF1A (P=0.042), PPARG (P=0.018), STAT3 (P=0.013), and CX3CL1 (P=0.038) mRNA expression in comparison with the NGT group. The women with NGT at the 1st visit who later developed GDM had significantly higher fasting glucose (P=0.01), HOMA-IR (P=0.004), and TLR2 mRNA expression (P=0.04), as well as lower ISSI2 (P=0.01) and disposition indices, DI₃₀ (P=0.03) and DI₁₂₀ (P=0.01), than had the women who remained normoglycemic. CONCLUSIONS Our results suggest that elevated TLR2 expression, as well as higher fasting glucose and lower compensation for increased insulin resistance, may represent early metabolic disturbances in the development of GDM.

Prognostic markers for the development of type 1 diabetes in first-degree relatives of diabetic patients

INTRODUCTION The aim of this study was to evaluate beta-cell function and insulin resistance in relation to the occurrence of anti-islet antibodies in first degree relatives of patients with type 1 diabetes (T1D). MATERIAL AND METHODS The group studied consisted of 90 relatives and 60 healthy individuals without a family history of diabetes. An intravenous glucose tolerance test (IVGTT) was performed in all participants and the first phase insulin response index (FPIR) was calculated. Serum concentrations of GADA, IAA and IA-2A were measured by RIA. HOMA-IR and HOMA%B indices were calculated using a computer calculator from website. RESULTS At least one positive antibody was found in 28 relatives (31.1%) but in none of the controls. The most frequently detected antibodies were IAA (22.2%). The relatives of diabetic patients had significantly higher fasting insulin level (p), significantly lower FPIR index(p), as well as higher HOMA-IR (p) and lower HOMA%B (p) compared to the controls. A positive correlation between IAA concentration and HOMA-IR (r = 0.287, p < 0.005) and a negative correlation between IAA level and HOMA%B (r = -0.226, p < 0.05) were also shown. CONCLUSIONS Our results confirmed that more than 30% of the first-degree relatives of diabetic patients have positive markers of autoimmune beta-cell destruction. The study showed also that these individuals, in spite of normal glucose tolerance, have markedly decreased beta-cell secretory reserve and decreased sensitivity to insulin action, strongly suggesting an increased risk for developing diabetes later in life.

The IL-6/IL-6R/sgp130 system and Th17 associated cytokines in patients with gestational diabetes

INTRODUCTION Interleukin-6 (IL-6) is a pleiotropic cytokine which signals through a cell surface receptor complex consisting of a cognatereceptor subunit (IL-6R) and glycoprotein 130 (gp130), which is considered an antagonist to the IL-6R/IL-6 pathway. The aim of the present study was to assess IL-6/IL-6R/gp130 system and Th17 associated cytokines in different time points during and after pregnancy in women with gestational diabetes mellitus (GDM) and normal glucose tolerance (NGT). MATERIAL AND METHODS Serum levels of IL-6, sIL6R, sgp130, IL-17 and IL-23 were measured in 91 women divided into three groups: GDMin the 24th-28th week of gestation (visit 1), NGT at the 1st visit and GDM in the 29th-32nd week, and NGT at both visits. RESULTS The patients with GDM recognised at the 1st visit had significantly higher IL-6 (p = 0.02) and sgp130 (p = 0.03) concentrations than had the women with NGT, whereas the women with GDM diagnosed at the 2nd visit had elevated sIL-6R concentrations (p = 0.03). The patients with low sIL-6R but high sgp130 concentration had significantly higher glucose levels (p = 0.04) and lower IL-6 values (p = 0.04) than had the patients with low sIL-6R and sgp130 concentrations. IL-17 and IL-23 were detected in approximately one-third of the population studied. A trend towards higher IL-17 levels was observed in the subjects with GDM, but the differences were not significant. CONCLUSIONS Our results suggest that an increased serum sgp130 concentration in the patients with GDM might represent a compensatory mechanism, controlling intracellular IL-6 signalling and preventing the activation of the IL-6/IL-6R pathway.

The association of bone turnover markers with pro- and anti-inflammatory adipokines in patients with gestational diabetes

OBJECTIVE The aim of the study was to assess differences in circulating osteocalcin (OC) and osteoprotegerin (OPG), as well as in their expression in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and placental tissue obtained from patients with gestational diabetes mellitus (GDM) and normal glucose tolerance (NGT). MATERIALS AND METHOD Serum levels of OC, OPG and soluble nuclear factor-kB ligand (sRANKL) were measured in 49 women with GDM and 30 subjects with NGT between weeks 24-32 of gestation, and three months after childbirth. OC and OPG mRNA expression was measured in 23 patients with GDM and 23 women with NGT at term, using quantitative real-time RT-PCR. RESULTS The patients with GDM had decreased OC mRNA expression in SAT (p=0.015), lower adiponectin mRNA expression in VAT (p=0.039), and a lower circulating adiponectin level (p=0.04). Multiple regression analysis revealed that serum adiponectin was significantly associated with OC mRNA expression in SAT (b=0.49, p=0.03). Three months postpartum, the OPG/sRANKL ratio was markedly higher in the subjects with prior GDM (p=0.03) and correlated positively with HbA1c (R=0.33; p=0.04), fasting insulin (R=0.35; p=0.03) and HOMA-IR (R=0.34; p=0.04). CONCLUSIONS In the patients with GDM decreased OC mRNA expression in SAT might be associated with a reduced stimulatory effect on adiponectin expression in adipose tissue. On the other hand, higher OPG/sRANKL ratio suggests a better protection against bone loss in the subjects with prior GDM.