Obesity-related parameters in carriers of some BDNF genetic variants may depend on daily dietary macronutrients intake

Some common single-nucleotide polymorphisms of the brain-derived neurotrophic factor (BDNF) gene have been associated not only with the neurodegenerative diseases but also with some eating disorders. The aim of this study was to assess the possible differences in the obesity-related and glucose metabolism parameters between some BDNF genotypes', that may depend on the daily energy and macronutrients intake. In 484 adult participants we performed the anthropometric measurements, body composition analysis, and body fat distribution. The daily dietary intake was assessed using the 3-day food intake diaries. Blood glucose and insulin concentrations were measured at fasting and during oral glucose tolerance tests. Moreover, the visceral adipose tissue/subcutaneous adipose tissue (VAT/SAT) ratio and homeostatic model assessment of insulin resistance were calculated. We noted that participants carrying the GG genotype had lower skeletal muscle mass and fat free mass (FFM) when carbohydrate intake was > 48%, whereas they presented higher fat-free mass (FFM), and surprisingly higher total cholesterol and LDL-C concentrations when daily fiber intake was > 18 g. Moreover, in these subjects we noted higher waist circumference, BMI, and fasting glucose and insulin concentrations, when > 18% of total daily energy intake was delivered from proteins, and higher VAT content and HDL-C concentrations when > 30% of energy intake was derived from dietary fat. Our results suggest that glucose homeostasis and obesity-related parameters in carriers of some common variants of BDNF gene, especially in the GG (rs10835211) genotype carriers, may differ dependently on daily energy, dietary macronutrients and fiber intake.

Gas Chromatography-Mass Spectroscopy-Based Metabolomics Analysis Reveals Potential Biochemical Markers for Diagnosis of Gestational Diabetes Mellitus

Due to many adverse effects of gestational diabetes mellitus (GDM) on the mother and fetus, its diagnosis is crucial. The presence of GDM can be confirmed by an abnormal fasting plasma glucose level (aFPG) and/or oral glucose tolerance test (OGTT) performed mostly between 24 and 28 gestational week. Both aFPG and abnormal glucose tolerance (aGT) are used to diagnose GDM. In comparison to measurement of FPG, OGTT is time-consuming, usually inconvenient for the patient, and very often needs to be repeated. Therefore, it is necessary to seek tests that will be helpful and convenient to diagnose GDM. For this reason, we investigated the differences in fasting serum metabolites between GDM women with abnGM and normal FPG (aGT-GDM group), with aFPG and normal glucose metabolism (aFPG-GDM group) as well as pregnant women with normal glucose tolerance (NGT) being a control group. Serum metabolites were measured by an untargeted approach using gas chromatography–mass spectrometry (GC–MS). In the discovery phase, fasting serum samples collected from 79 pregnant women (aFPG-GDM, n = 24; aGT-GDM, n = 26; NGT, n = 29) between 24 and 28 weeks of gestation (gwk) were fingerprinted. A set of metabolites (α–hydroxybutyric acid (α–HB), β–hydroxybutyric acid (β–HB), and several fatty acids) significant in aGT-GDM vs NGT but not significant in aFPG-GDM vs NGT comparison in the discovery phase was selected for validation. These metabolites were quantified by a targeted GC–MS method in a validation cohort consisted of 163 pregnant women (aFPG-GDM, n = 51; aGT-GDM, n = 44; and NGT, n = 68). Targeted analyses were also performed on the serum collected from 92 healthy women in the first trimester (8–14 gwk) who were NGT at this time, but in the second trimester (24–28 gwk) they were diagnosed with GDM. It was found that α–HB, β–HB, and several fatty acids were associated with aGT-GDM. A combination of α–HB, β–HB, and myristic acid was found highly specific and sensitive for the diagnosis of GDM manifested by aGT-GDM (AUC = 0.828) or to select women at a risk of aGT-GDM in the first trimester (AUC = 0.791). Our findings provide new potential markers of GDM and may have implications for its early diagnosis.

Dietary Fiber Intake May Influence the Impact of FTO Genetic Variants on Obesity Parameters and Lipid Profile-A Cohort Study of a Caucasian Population of Polish Origin

Genetic and environmental factors play a key role in the development of obesity. The aim of this study was to explore the potential effect of fat mass and obesity-associated (FTO) rs3751812, rs8050136, rs9939609, rs6499640, rs8044769, and rs7190492 genotypes and dietary fiber intake on the obesity-related parameters and lipid profile in the Polish population. We selected 819 Polish Caucasian adult subjects (52.5% female and 47.5% male) for a final gene–diet interaction analysis, with mean BMI 28.5 (±6.6) kg/m². We performed measurements of anthropometric parameters, total body fat content and distribution, and blood glucose, insulin, and lipid concentrations. Daily fiber intake was analyzed based on 3-day food-intake diaries, and daily physical activity was evaluated based on the International Physical Activity Questionnaire—Long Form. Our study shows that carriers of the GG genotype (rs3751812), CC genotype (rs8050136), and GG genotype (rs6499640) presented lower hip circumference if daily fiber intake was above 18 g per day. Additionally, GG genotype (rs3751812) and CC genotype (rs8050136) carriers showed surprisingly higher total cholesterol and LDL-cholesterol levels when they were stratified to the group with higher than median fiber intake. The results of this study highlight that high-fiber diets may positively affect anthropometric parameters but may also worsen lipid profile dependent on the FTO genotype.

An Association between Diet and MC4R Genetic Polymorphism, in Relation to Obesity and Metabolic Parameters-A Cross Sectional Population-Based Study

The melanocortin-4 receptor (MC4R) gene harbours one of the strongest susceptibility loci for obesity and obesity-related metabolic consequences. We analysed whether dietary factors may attenuate the associations between MC4R genotypes and obesity and metabolic parameters. In 819 participants genotyped for common MC4R polymorphisms (rs17782313, rs12970134, rs633265, and rs135034), the anthropometric measurements, body fat content and distribution (visceral and subcutaneous adipose tissue, VAT and SAT, respectively), and blood glucose, insulin, total-, LDL-, HDL-cholesterol, triglycerides concentrations, and daily macronutrient intake were assessed. ANOVA or Kruskal–Wallis tests were used, and multivariate linear regression models were developed. We observed that the CC genotype carriers (rs17782313) presented higher VAT, VAT/SAT ratio, fasting blood glucose and triglyceride concentrations when they were stratified to the upper quantiles of protein intake. An increase in energy derived from proteins was associated with higher BMI (Est. 5.74, R² = 0.12), body fat content (Est. 8.44, R² = 0.82), VAT (Est. 32.59, R² = 0.06), and VAT/SAT ratio (Est. 0.96, R² = 0.05). The AA genotype carriers (rs12970134) presented higher BMI, body fat, SAT and VAT, fasting blood glucose, triglycerides and total cholesterol concentrations. An increase in energy derived from proteins by AA carriers was associated with higher VAT (Est.19.95, R² = 0.06) and VAT/SAT ratio (Est. 0.64, R² = 0.05). Our findings suggest that associations of the common MC4R SNPs with obesity and its metabolic complications may be dependent on the daily dietary intake, which may open new areas for developing personalised diets for preventing and treating obesity and obesity-related comorbidities.

The Response of Mitochondrial Respiration and Quantity in Skeletal Muscle and Adipose Tissue to Exercise in Humans with Prediabetes

Background: Mitochondrial dysfunction has been implicated in the pathogenesis of type 2 diabetes, but its contribution to the early stages of dysglycemia remains poorly understood. By collecting a high-resolution stage-based spectrum of dysglycemia, our study fills this gap by evaluating derangement in both the function and quantity of mitochondria. We sampled mitochondria in skeletal muscle and subcutaneous adipose tissues of subjects with progressive advancement of dysglycemia under a three-month exercise intervention. Methods: We measured clinical metabolic parameters and gathered skeletal muscle and adipose tissue biopsies before and after the three-month exercise intervention. We then assayed the number of mitochondria via citrate synthase (CS) activity and functional parameters with high-resolution respirometry. Results: In muscle, there were no differences in mitochondrial quantity or function at baseline between normoglycemics and prediabetics. However, the intervention caused improvement in CS activity, implying an increase in mitochondrial quantity. By contrast in adipose tissue, baseline differences in CS activity were present, with the lowest CS activity coincident with impaired fasting glucose and impaired glucose tolerance (IFG + IGT). Finally, CS activity, but few of the functional metrics, improved under the intervention. Conclusions: We show that in prediabetes, no differences in the function or amount of mitochondria (measured by CS activity) in skeletal muscle are apparent, but in adipose tissue of subjects with IFG + IGT, a significantly reduced activity of CS was observed. Finally, metabolic improvements under the exercise correlate to improvements in the amount, rather than function, of mitochondria in both tissues.

Metabolomic Profile of Skeletal Muscle and Its Change Under a Mixed-Mode Exercise Intervention in Progressively Dysglycemic Subjects

Skeletal muscles play an essential role in whole-body glucose homeostasis. They are a key organ system engaged in the development of insulin resistance, and also a crucial tissue mediating the beneficial metabolic effects of physical activity. However, molecular mechanisms underlying both these processes in skeletal muscle remain unclear. The aim of our study was to compare metabolomic profiles in skeletal muscle of patients at different stages of dysglycemia, from normoglycemia through prediabetes to T2D, and its changes under a mixed-mode (strength and endurance) exercise intervention. We performed targeted metabolomics comprising several major metabolite classes, including amino acids, biogenic amines and lipid subgroups in skeletal muscles of male patients. Dysglycemic groups differed significantly at baseline in lysophosphatidylcholines, phosphatidylcholines, sphingomyelins, glutamine, ornithine, and carnosine. Following the exercise intervention, we detected significant changes in lipids and metabolites related to lipid metabolism, including in ceramides and acylcarnitines. With their larger and more significant change over the intervention and among dysglycemic groups, these findings suggest that lipid species may play a predominant role in both the pathogenesis of type 2 diabetes and its protection by exercise. Simultaneously, we demonstrated that amino acid metabolism, especially glutamate dysregulation, is correlated to the development of insulin resistance and parallels disturbances in lipid metabolites.

Sex-Specific Glucose Homeostasis and Anthropometric Responses to Sleeve Gastrectomy in Obese Patients

Bariatric surgery rapidly and effectively treats obesity and its comorbidities like dysregulated glucose homeostasis. Despite the sex-balanced incidence of obesity in most human populations, women have sought this intervention more frequently than men. However, as the number of bariatric surgeries rapidly rises, it is increasingly urgent to understand how sex-specific differences may emerge in metabolic and anthropometric parameters. Hundred fifty-four obese patients (47% men and 53% women) from the Bialystok Bariatric Surgery Study underwent sleeve gastrectomy and were measured for 25 parameters at baseline (immediately prior to surgery) and at four follow-up visits over one year. We used generalized linear mixed models to detect sex-specific differences in the time series of responses parameters. Unlike most previous studies with older cross-sections of men than women, our cohort was age-matched, and men were less healthy at baseline. Of parameters that showed a significant cohort-wide (across-sex) response, 14 (56%) also showed sex-specific responses with men improving more than women. In particular, men remitted in diabetes symptoms more strongly, rapidly, and durably than women. Taken together, our results indicate that men may benefit more from sleeve gastrectomy and that this difference in improvement may be related to more progressed morbidity prior to surgery independent of age.

Clusters of Glycemic Response to Oral Glucose Tolerance Tests Explain Multivariate Metabolic and Anthropometric Outcomes of Bariatric Surgery in Obese Patients

Glycemic responses to bariatric surgery are highly heterogeneous among patients and defining response types remains challenging. Recently developed data-driven clustering methods have uncovered subtle pathophysiologically informative patterns among patients without diabetes. This study aimed to explain responses among patients with and without diabetes to bariatric surgery with clusters of glucose concentration during oral glucose tolerance tests (OGTTs). We assessed 30 parameters at baseline and at four subsequent follow-up visits over one year on 154 participants in the Bialystok Bariatric Surgery Study. We applied latent trajectory classification to OGTTs and multinomial regression and generalized linear mixed models to explain differential responses among clusters. OGTT trajectories created four clusters representing increasing dysglycemias that were discordant from standard diabetes diagnosis criteria. The baseline OGTT cluster increased the predictive power of regression models by over 31% and aided in correctly predicting more than 83% of diabetes remissions. Principal component analysis showed that the glucose homeostasis response primarily occurred as improved insulin sensitivity concomitant with improved the OGTT cluster. In sum, OGTT clustering explained multiple, correlated responses to metabolic surgery. The OGTT is an intuitive and easy-to-implement index of improvement that stratifies patients into response types, a vital first step in personalizing diabetic care in obese subjects.

Metabolomics Reveal Altered Postprandial Lipid Metabolism After a High-Carbohydrate Meal in Men at High Genetic Risk of Diabetes

BACKGROUND

The transcription factor 7-like 2 (TCF7L2) gene confers one of the strongest genetic predispositions to type 2 diabetes, but diabetes development can be modified by diet.

OBJECTIVE

The aim of our study was to evaluate postprandial metabolic alterations in healthy men with a high genetic risk of diabetes, after two meals with varying macronutrient content.

METHODS

The study was conducted in 21 homozygous nondiabetic men carrying the high-risk (HR, n = 8, age: 31.2 ± 6.3 y, body mass index (BMI, kg/m2) 28.5 ± 8.1) or low-risk (LR, n = 13, age: 35.2 ± 10.3 y, BMI: 28.1 ± 6.4) genotypes at the rs7901695 locus. During two meal challenge test visits subjects received standardized isocaloric (450 kcal) liquid meals: high-carbohydrate (HC, carbohydrates: 89% of energy) and normo-carbohydrate (NC, carbohydrates: 45% of energy). Fasting (0 min) and postprandial (30, 60, 120, 180 min) plasma samples were analyzed for metabolite profiles through untargeted metabolomics. Metabolic fingerprinting was performed on an ultra-high-performance liquid chromatography (UHPLC) system connected to an iFunnel quadrupole-time-of-flight (Q-TOF) mass spectrometer.

RESULTS

In HR-genotype men, after the intake of an HC-meal, we noted a significantly lower area under the curves (AUCs) of postprandial plasma concentrations of most of the phospholipids (-37% to -53%, variable importance in the projection (VIP) = 1.2-1.5), lysophospholipids (-29% to -86%, VIP = 1.1-2.6), sphingolipids (-32% to -47%, VIP = 1.1-1.3), as well as arachidonic (-36%, VIP = 1.4) and oleic (-63%, VIP = 1.3) acids, their metabolites: keto- and hydoxy-fatty acids (-38% to -78%, VIP = 1.3-2.5), leukotrienes (-65% to -83%, VIP = 1.4-2.2), uric acid (-59%, VIP = 1.5), and pyroglutamic acid (-65%, VIP = 1.8). The AUCs of postprandial sphingosine concentrations were higher (125-832%, VIP = 1.9-3.2) after the NC-meal, AUCs of acylcarnitines were lower (-21% to -61%, VIP = 1.1-2.4), and AUCs of fatty acid amides were higher (51-508%, VIP = 1.7-3.1) after the intake of both meals.

CONCLUSIONS

In nondiabetic men carrying the TCF7L2 HR genotype, subtle but detectable modifications in intermediate lipid metabolism are induced by an HC-meal. This trial was registered at www.clinicaltrials.gov as NCT03792685.

The Type 2 Diabetes Susceptibility PROX1 Gene Variants Are Associated with Postprandial Plasma Metabolites Profile in Non-Diabetic Men

The prospero homeobox 1 (PROX1) gene may show pleiotropic effects on metabolism. We evaluated postprandial metabolic alterations dependently on the rs340874 genotypes, and 28 non-diabetic men were divided into two groups: high-risk (HR)-genotype (CC-genotype carriers, n = 12, 35.3 ± 9.5 years old) and low-risk (LR)-genotype (allele T carriers, n = 16, 36.3 ± 7.0 years old). Subjects participated in two meal-challenge-tests with high-carbohydrate (HC, carbohydrates 89%) and normo-carbohydrate (NC, carbohydrates 45%) meal intake. Fasting and 30, 60, 120, and 180 min after meal intake plasma samples were fingerprinted by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). In HR-genotype men, the area under the curve (AUC) of acetylcarnitine levels was higher after the HC-meal [+92%, variable importance in the projection (VIP) = 2.88] and the NC-meal (+55%, VIP = 2.00) intake. After the NC-meal, the HR-risk genotype carriers presented lower AUCs of oxidized fatty acids (−81–66%, VIP = 1.43–3.16) and higher linoleic acid (+80%, VIP = 2.29), while after the HC-meal, they presented lower AUCs of ornithine (−45%, VIP = 1.83), sphingosine (−48%, VIP = 2.78), linoleamide (−45%, VIP = 1.51), and several lysophospholipids (−40–56%, VIP = 1.72–2.16). Moreover, lower AUC (−59%, VIP = 2.43) of taurocholate after the HC-meal and higher (+70%, VIP = 1.42) glycodeoxycholate levels after the NC-meal were observed. Our results revealed differences in postprandial metabolites from inflammatory and oxidative stress pathways, bile acids signaling, and lipid metabolism in PROX1 HR-genotype men. Further investigations of diet–genes interactions by which PROX1 may promote T2DM development are needed.

The Role of Muscle Decline in Type 2 Diabetes Development: A 5-Year Prospective Observational Cohort Study

The major risk factors of T2DM (type 2 diabetes mellitus) development are still under investigation. We evaluate the possible risk factors associated with type 2 diabetes (T2DM) in adult subjects during a five-year prospective cohort study. We recruited 1160 subjects who underwent oral glucose tolerance test, anthropometric measurements, and body composition and body fat distribution analysis at a baseline visit and again at follow-up after approximately five years. The conclusions of this study are based on observation of 219 subjects who attended both the first and follow-up visits. The fasting serum insulin was measured, and HOMA-IR (homeostatic model assessment of insulin resistance) was calculated. During the follow-up period, T2DM was diagnosed in 7.4% of participants, impaired fasting glucose in 37.7%, and impaired glucose tolerance in 9.3%. Logistic regression models, adjusted for age, were constructed. The changes in glucose concentration, visceral fat tissue content, insulin resistance, and %loss of muscle mass were chosen as the potential predictors for T2DM development. A set of independent variables was extracted. The constructed feature set comprised change in HOMA-IR (OR (odds ratio) = 1.01, p < 0.01) and change in %loss of muscle mass (OR = 0.84, p < 0.03). With an aim to validate the prediction capability using the selected attributes, a support vector machine classifier and leave-one-out cross-validation procedure was applied, yielding 92.78% classification accuracy. Our results show the correlation between the %loss of muscle mass and T2DM development in adults, independent of changes in insulin resistance.

The MC4R genetic variants are associated with lower visceral fat accumulation and higher postprandial relative increase in carbohydrate utilization in humans

Purpose

The interactions between lifestyle and genetic factors play an important role in obesity development. Mutations in melanocortin-4-receptor (MC4R) gene are one of the most common cause of monogenic obesity, however, the functional effects of polymorphic variants near MC4R gene in general populations remain uncertain. The aim of our study was to analyze whether the common single nucleotide polymorphisms (SNPs) of MC4R gene influence the food preferences, physical activity, body fat content and distribution, as well as fasting and postprandial energy expenditure and substrates utilization.

Methods

We genotyped previously identified MC4R SNPs: rs17782313, rs633265, rs1350341, rs12970134 in 927 subjects, who underwent anthropometric, total body fat content, visceral (VAT) and subcutaneous adipose tissue (SAT) measurements, and daily physical activity and dietary intake analysis. In randomly selected 47 subjects the energy expenditure, carbohydrate and lipid utilizations were evaluated in fasting state and after high-carbohydrate and control meals intake.

Results

We found the significant associations between studied SNPs of MC4R gene and VAT and VAT/SAT ratio. Moreover, the GG genotype carriers of rs1350341, who had the lowest VAT accumulation (p = 0.012), presented higher relative increase in postprandial carbohydrate utilization (p = 0.013, p = 0.024).

Conclusions

We have observed that common SNPs of the MC4R gene influence the body fat content and distribution, as well as relative increase in postprandial carbohydrate utilization. We believe that our study may help to understand better the impact of MC4R gene on obesity development, and to help to provide personalized prevention/treatment strategies to fight against obesity and its metabolic consequences.

The Differences in Postprandial Serum Concentrations of Peptides That Regulate Satiety/Hunger and Metabolism after Various Meal Intake, in Men with Normal vs. Excessive BMI

The energy balance regulation may differ in lean and obese people. The purposes of our study were to evaluate the hormonal response to meals with varying macronutrient content, and the differences depending on body weight.

METHODS

The crossover study included 46 men, 21⁻58 years old, normal-weight and overweight/obese. Every subject participated in two meal-challenge-tests with high-carbohydrate (HC), and normo-carbohydrate (NC) or high-fat (HF) meals. Fasting and postprandial blood was collected for a further 240 min, to determine adiponectin, leptin and total ghrelin concentrations.

RESULTS

In normal-weight individuals after HC-meal we observed at 60min higher adiponectin concentrations (12,554 ± 1531 vs. 8691 ± 1070 ng/mL, p = 0.01) and significantly (p < 0.05) lower total ghrelin concentrations during the first 120 min, than after HF-meal intake. Fasting and postprandial leptin levels were significantly (p < 0.05) higher in overweigh/obese men. Leptin concentrations in normal-weight men were higher (2.72 ± 0.8 vs. 1.56 ± 0.4 ng/mL, p = 0.01) 180 min after HC-meal than after NC-meal intake.

CONCLUSIONS

Our results suggest that in normal-body weight men we can expect more beneficial leptin, adiponectin, and total ghrelin response after HC-meal intake, whereas, in overweight/obese men, the HC-meal intake may exacerbate the feeling of hunger, and satiety may be induced more by meals with lower carbohydrate content.

The relationship between the leptin/ghrelin ratio and meals with various macronutrient contents in men with different nutritional status: a randomized crossover study

BACKGROUND

Hormones, which influence satiety and hunger, play a significant role in body energy balance regulation. Ghrelin is a peptide that plays an important role in short-term appetite regulation, whereas leptin is a factor that controls long-term energy balance and is considered as a satiety hormone. The aim of this study was to evaluate the leptin/ghrelin ratio in a fasting state and after the intake of meals with varying macronutrient contents and to assess the possible differences between normal body weight and overweight/obese men.

METHODS

We examined 46 healthy adult men (23 with normal body weight and 23 overweight/obese) aged 21-58, who were divided into two groups. In the crossover study, participants received isocaloric (450 kcal) meals with different macronutrient contents: men from the first group received high-carbohydrate (HC) and normo-carbohydrate (NC) meals, and in the second group, participants received high-carbohydrate and high-fat (HF) meals. The ratio of leptin/ghrelin levels was calculated from leptin and total ghrelin serum concentrations in a fasting state and 30, 60, 120, 180 and 240 min after meal intake. One-way ANOVA and Wilcoxon signed-rank tests were carried out. The normality of the variable distribution was checked with the Shapiro-Wilk test, the homogeneity of variances was verified with the Levene test, and the false discovery rate p-value adjustment method was used.

RESULTS

The leptin/ghrelin ratio was significantly higher in overweight/obese men than individuals with normal body weight in a fasting state, as well as postprandially. We observed trends towards a higher leptin/ghrelin ratio values from the 60 min after HC-meal intake compared to the NC- and HF-meals in normal body weight participants, while in overweight/obese men, we did not note any significant differences dependent on the meal type.

CONCLUSIONS

We have observed a significantly different postprandial leptin/ghrelin ratio in normal body weight and overweight/obese men, and our results suggest that in men with normal body weight, a greater feeling of satiety may occur after high-carbohydrate meal intake, which was not noted in the overweight/obese individuals.

Evaluation of Energy Expenditure and Oxidation of Energy Substrates in Adult Males after Intake of Meals with Varying Fat and Carbohydrate Content

Obesity is a result of positive energy balance. The aim of this study was to measure (in crossover trials) the energy expenditure and oxidation of glucose and lipids, both at the fasting state and after an intake of meals with a varying macronutrient content, in normal-weight and overweight/obese people. In the study, 46 healthy adult males (23 with normal body weight and 23 overweight/obese), aged 21–58, were examined. During two consecutive visits, subjects received isocaloric standardized meals (450 kcal) with different content of basic nutrients. Resting metabolic rate and carbohydrate and fat utilization were evaluated during the fasting state and postprandially, using an indirect calorimetry method. Energy expenditure was higher in people with normal body weight and slightly higher after the high-carbohydrate meal. In overweight/obese people, increased expenditure was noted after normo-carbohydrate meal intake. The high-fat meal induced lower postprandial thermal response compared to a high-carbohydrate meal, both in people with normal body weight and in overweight/obese men. Glucose utilization was higher after the high-carbohydrate meal, and it was higher in the normal body weight group than in overweight/obese people. In addition, overweight/obese people showed a lower level of fatty acid oxidation under fasting conditions which, together with limited ability to oxidize energy substrates, depending on their availability, indicates that these people are characterized by lower metabolic flexibility.

Effect of nitrosative stress on extracellular nucleotide metabolism in endothelial cells

Mechanisms of free radical injury involve chemical modification of proteins, lipid derivatives and nucleic acids and consequent loss of its function. However, specific targets and exact sequence of events has not been fully clarified. We determined whether extracellular enzymes that are involved in adenosine formation such as ecto-5'nucleotidase (e5N) and removal such as extracellular form of adenosine deaminase (eADA) could be affected by peroxynitrite. We used intact cell assay system that involves exposure of cultured HMEC-1 cells to substrates followed by HPLC analysis of conversion of substrates into products. We found that e5N and ADA activities decreased by 20-40% after incubation for 20 or 60 minutes with 30 μM peroxynitrite. Decrease of cellular ATP and NAD was also observed. We conclude that besides other cytotoxic effects modification of extracellular enzymes of nucleotide metabolism could be important target for free radical injury.

The rs340874 PROX1 type 2 diabetes mellitus risk variant is associated with visceral fat accumulation and alterations in postprandial glucose and lipid metabolism

Large-scale meta-analyses of genome-wide association studies have recently confirmed that the rs340874 single-nucleotide polymorphism in PROX1 gene is associated with fasting glycemia and type 2 diabetes mellitus; however, the mechanism of this link was not well established. The aim of our study was to evaluate the functional/phenotypic differences related to rs340874 PROX1 variants. The study group comprised 945 subjects of Polish origin (including 634 with BMI > 25) without previously known dysglycemia. We analyzed behavioral patterns (diet, physical activity), body fat distribution and glucose/fat metabolism after standardized meals and during the oral glucose tolerance test. We found that the carriers of the rs340874 PROX1 CC genotype had higher nonesterified fatty acids levels after high-fat meal (p = 0.035) and lower glucose oxidation (p = 0.014) after high-carbohydrate meal in comparison with subjects with other PROX1 genotypes. Moreover, in subjects with CC variant, we found higher accumulation of visceral fat (p < 0.02), but surprisingly lower daily food consumption (p < 0.001). We hypothesize that lipid metabolism alterations in subjects with the PROX1 CC genotype may be a primary cause of higher glucose levels after glucose load, since the fatty acids can inhibit insulin-stimulated glucose uptake by decreasing carbohydrate oxidation. Our observations suggest that the PROX1 variants have pleiotropic effect on disease pathways and it seem to be a very interesting goal of research on prevention of obesity and type 2 diabetes mellitus. The study may help to understand the mechanisms of visceral obesity and type 2 diabetes mellitus risk development.

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.

Serum irisin concentration in women with gestational diabetes

Irisin is a novel myokine and adipokine which induces an increase in total body energy expenditure, improving insulin sensitivity and glucose tolerance in experimental animals. In the present study, serum irisin concentration was measured by an enzyme immunoassay in 130 women with gestational diabetes mellitus (GDM) and 140 BMI-matched patients with normal glucose tolerance (NGT). Median irisin level was significantly lower in the patients with GDM than in the NGT subjects (1703.3 [1354.8-2097.9 ng/ml] versus 1873.8 [1519.8-2294.8 ng/ml], p = 0.01); however, 3 months after childbirth its concentrations did not differ markedly between the two groups (1165.9 [872.1-1497.5] ng/ml versus 1139.0 [984.0-1376.7] ng/ml). In the whole group, irisin concentration correlated negatively with 2 h glucose level (R = -0.14, p = 0.03). In the women with NGT, irisin concentration correlated positively with IS(OGTT) (R = 0.22, p = 0.04) and the disposition index (DI(120)) (R = 0.24, p = 0.03), as well as negatively with 2 h insulin level (R = -0.23, p = 0.03) and HOMA-IR (R = -0.24, p = 0.02). Multiple regression analysis revealed that 2 h glucose and DI(120) were the only variables significantly influencing serum irisin (β = 0.158, p = 0.03 and β = 0.159, p = 0.02, respectively). Our results suggest that serum irisin concentration increases markedly in pregnant women, but this increase seems to be significantly lower in patients with GDM.

Potential first trimester metabolomic biomarkers of abnormal birth weight in healthy pregnancies

OBJECTIVE

Macrosomia and low birth weight (LBW) can be associated with pregnancy complications and may affect the long-term health of the child. The aim of this study was to evaluate the metabolomic serum profiles of healthy pregnant women to identify early biomarkers of macrosomia and LBW and to understand mechanisms leading to abnormal fetal growth not related to mother's body mass index or presence of gestational diabetes.

METHOD

Serum samples from 770 women were collected between the 12th and 14th gestational week. Delivery samples were divided into three groups according to the infant birth weight as follows: low, <2500 g; normal, 2500-4000 g; and high >4000 g. Samples from women with any complications of pregnancy were excluded. Serum fingerprinting was performed by LC-QTOF-MS.

RESULTS

Lower levels of phospholipids, lysophospholipids, and monoacylglycerols; low vitamin D3 metabolites; and increased bilirubin level were associated with macrosomia. Because most changes involved lipids, as a concept of validation, adipocyte fatty acid-binding protein (A-FABP) levels were measured and found correlated with the studied lipids and birth weight.

CONCLUSION

Serum fingerprinting in early pregnancy can predict the risk of macrosomia. Serum levels of A-FABP and several lipids are promising prognostic markers for macrosomia in healthy pregnancies.

Elevated percentage of HLA-DR⁺ and ICAM-1⁺ conjunctival epithelial cells in active Graves' orbitopathy

Background

To evaluate if conjunctival epithelial cells’ expression of HLA-DR and ICAM-1 could be helpful as early topical markers of inflammation in Graves’ orbitopathy (GO).

Methods

The ocular examination evaluated a clinical activity score (CAS) by assessment of clinical features, (e.g., eyelid or conjunctival inflammation, lid width, lid closure, proptosis, ocular motility). Conjunctival epithelial cell specimens for flow-cytometric evaluations of ICAM-I and HLADR expression were collected by impression cytology from ten eyes with active GO (CAS ≥ 4 and duration ≤ 12 months), from 15 eyes with Graves’ disease (GD) without active GO (CAS 0–2) and from 15 normal specimens without any ocular disorders.

Results

The percentage of HLA-DR + conjunctival epithelial cells was significantly elevated in patients with active GO comparing to GD without active GO and healthy controls, 10.7 % (8.5–17.7) and 7.78 % (3.92–10.1) (p < 0.05) vs. control 4.89 % (3.5–5.5) (p < 0.005), respectively. The expression of ICAM − 1+ conjunctival epithelial cells was greater only in patients with GO vs. controls, 5.5 % (4.8–7.03) and 1.46 % (0.69–2.51) (p < 0.005), respectively.

Conclusion

The percentage of HLA-DR⁺ and ICAM-1⁺ conjunctival epithelial cells in patients with the active GO may serve as a topical inflammation marker in Graves’ orbitopathy.

Measurement of the dipole polarizability of the unstable neutron-rich nucleus 68Ni

The E1 strength distribution in 68Ni has been investigated using Coulomb excitation in inverse kinematics at the R3B-LAND setup and by measuring the invariant mass in the one- and two-neutron decay channels. The giant dipole resonance and a low-lying peak (pygmy dipole resonance) have been observed at 17.1(2) and 9.55(17) MeV, respectively. The measured dipole polarizability is compared to relativistic random phase approximation calculations yielding a neutron-skin thickness of 0.17(2) fm. A method and analysis applicable to neutron-rich nuclei has been developed, allowing for a precise determination of neutron skins in nuclei as a function of neutron excess.

Glucocorticoids upregulate decreased IL-7 receptor expression in asthmatic patients and simian immunodeficiency virus-infected non-human primates

Signaling through interleukin-7 receptor (IL-7R) is essential for regulation of T-cell homeostasis and survival. Previously, we and others have found diminished IL-7R levels in simian immunodeficiency virus (SIV) - infected non-human primates and human immunodeficiency virus (HIV) - infected patients. To date, it remains unknown whether changes in IL-7R expression could also be linked to non-infectious inflammatory diseases such as asthma or anti-inflammatory drug use. Here, we investigated through flow cytometry the levels of IL-7R expression on CD4+ and CD4- T-cells in asthmatic patients in relation to disease severity, immune status and glucocorticoid (GC) use. In addition, we sought to evaluate the effects of in vivo and in vitro GC treatment on IL-7R expression in both asthmatic patients and SIV-infected non-human primates. We demonstrated that expression of IL-7R on peripheral blood CD4+ T-cells was significantly decreased in clinically stable GC-naive mild and moderate asthmatic patients. Accordingly, the development of asthmatic reaction following bronchial allergen challenge performed in sensitized subjects was associated with a significant drop in levels of IL-7R on circulating CD4+ T-cells. In contrast, CD4+ T-cells from both, mild and moderate, but not severe asthmatics, treated with inhaled GC displayed levels of IL-7R similar to that seen in healthy controls. We did not find significant differences with serum or sputum interleukin-7 levels among healthy controls and GC-naïve and GC-treated asthmatic patients. Furthermore, both in vitro GC treatment and short-term oral GC administration to asthmatic patients resulted in a significant enhancement of IL-7R. Similarly, we demonstrated that GC-stimulated T-cells from SIV-infected non-human primates up-regulated IL-7R expression. Accordingly, experimental short-term systemic in vivo administration of GC to SIV-infected macaques led to enhancement of IL-7R expression on circulating T-cells. Our data indicate that GC bear potential to recover diminished IL-7R expression, as well in asthma as in lentiviral infection.

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.

Circulating CXCL9 and CXCL10 as markers of activity of Graves' orbitopathy during treatment with corticosteroids and teleradiotherapy

The aim of the study was to assess the usefulness of circulating chemokines CXCL9 and CXCL10 measurements as surrogate markers of GO activity and as a guideline in therapeutic decision-making. Forty-two individuals were divided into 4 groups: 1. 15 euthyroid patients with clinical symptoms of orbitopathy (GO) who underwent corticosteroid therapy consisting of intravenous infusions of methylprednisolone (MP) and teleradiotherapy (TR); 2. 10 patients with hyperthyroid GD (Gtx); 3. 10 patients with GD in euthyreosis (Geu); and 4. 7 healthy volunteers age and sex-matched to groups 1-3. The serum samples were collected 24 h before MP, 24 h after first dose of MP, before TR and at the end of therapy. Serum CXCL9 and CXCL10 were determined by ELISA and TSH-Rab by RIA. There were significant reductions in CXCL9 and CXCL10 serum concentrations during CS and TR treatment as compared both to control group and to basal values in GO patients. Moreover, CXCL9 concentration was significantly diminished in comparison to controls in GO patients who were identified later as corticosteroid-respondent (p<0.001). In this latter group of patients, CXCL9 was also found to be significantly reduced 24 h after first dose of MP as compared to non-respondents (p<0.02). The high-degree positive correlation between CXCL9 and CXCL10 was found (R=0.8; p<0.001). Our results suggest that the increased concentrations of CXCL9 (and CXCL10), at least in part, reflect the activity of orbital inflammation and therefore these chemokines could serve as a guideline in therapeutic decision-making in patients with Graves' orbitopathy.

The expression of suppressor of cytokine signaling 1 and 3 in fat and placental tissue from women with gestational diabetes

The suppressor of cytokine signaling (SOCS) proteins are feedback inhibitors of signaling pathways induced by cytokines, hormones and growth factors. In the present study we measured the expression of SOCS1, SOCS3, interleukin-6 (IL-6), IL-6 receptor, IL-8 and leptin mRNA in paired samples of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and placental tissue obtained from 18 pregnant women with normal glucose tolerance (NGT) and 20 subjects with gestational diabetes mellitus (GDM), using quantitative RT-PCR. The patients with GDM had significantly higher IL-8 mRNA expression in VAT than the women with NGT (p = 0.007), whereas the expression of SOCS1, SOCS3 and other genes study did not differ significantly between the two groups. Stepwise regression analysis revealed that SOCS1 mRNA expression in VAT was significantly associated with prepregnancy BMI (β = -0.68, p = 0.03) and IL-8 mRNA expression (β = 0.66, p = 0.03), whereas SOCS3 mRNA expression in VAT was independently predicted by IL-6 mRNA expression (β = 0.94, p = 0.0002, R(2) = 0.88). In conclusion, our results did not show significant differences in SOCS1 and SOCS3 mRNA expression in adipose and placental tissue obtained from pregnant women with and without GDM.

Impact of the FTO gene variation on fat oxidation and its potential influence on body weight in women with polycystic ovary syndrome

CONTEXT

Polycystic ovary syndrome (PCOS) is a heterogeneous disorder where insulin resistance might be involved in the development of endocrine and metabolic abnormalities. It has recently been shown that the FTO gene modifies weight, fat mass and insulin sensitivity in women with PCOS, where its role might be larger than in other phenotypes.

OBJECTIVE

The aim of this study was to estimate the effect of a variation of the FTO gene on carbohydrate and lipid oxidation in PCOS women.

PATIENTS

The study group consisted of 65 women with PCOS and 28 healthy, normally menstruating women.

MEASUREMENTS

Clinical examination, anthropometric measurements, euglycaemic hyperinsulinaemic clamp and measurements of serum sex hormones were performed. Carbohydrate and lipid oxidation were evaluated with indirect calorimetry in the baseline state and during last 30 min of the clamp. The FTO rs9939609 polymorphism was genotyped using the restriction fragment length polymorphism method.

RESULTS

There were no differences in carbohydrate and lipid oxidation between PCOS and control women. In the PCOS group, TT homozygotes had higher baseline fat oxidation in comparison with carriers of the A allele (P = 0·018), which was not found in the control group. We did not observe the effect of the FTO gene variation on insulin-stimulated lipid oxidation and neither on the baseline nor on the insulin-stimulated carbohydrate oxidation.

CONCLUSION

Our data show that this FTO gene variation might influence the baseline lipid oxidation in PCOS patients. This might potentially be one of the mechanisms explaining the impact of the FTO gene on body weight in PCOS.

Serum interleukin-16 and RANTES during treatment of Graves' orbitopathy with corticosteroids and teleradiotherapy

INTRODUCTION

To assess the usefulness of circulating IL-16 and RANTES measurements as markers of Graves' orbitopathy (GO) activity and to estimate the role of these cytokines in GO pathogenesis.

MATERIAL AND METHODS

42 individuals were divided into four groups: Group 1 comprised 15 euthyroid patients with clinical symptoms of GO who underwent corticosteroid therapy consisting of intravenous infusions of methylprednisolone (MP) and teleradiotherapy (TR); Group 2 comprised ten patients with hyperthyroid GD (Gtx); Group 3 comprised ten patients with GD in euthyreosis (Geu); and Group 4 comprised seven healthy volunteers age- and sex-matched to Groups 1-3. Serum samples were collected 24 hours before the first dose of MP, 24 hours after the first dose of MP, before TR, and at the end of therapy. Serum IL-16 and RANTES were determined by ELISA and TSH-Rab by RIA.

RESULTS

Serum IL-16 levels in patients with GO were significantly elevated at the end of therapy: 346 pg/mL (257-538) compared to IL-16 values before treatment: 250 ng/mL (211-337) and to the control group. RANTES serum concentrations did not significantly differ between studied groups, and immunosuppressive treatment did not influence its level. A negative correlation between TSH-Rab and RANTES was found in all studied groups (R = -0.32, p 〈 0.01).

CONCLUSIONS

Our data suggests that IL-16 may exert an immunoregulatory effect in Graves' orbitopathy. Serum measurements of both IL-16 and RANTES may be clinically useful; however, establishing their place in the diagnostics and treatment monitoring of GO needs further research.

Hyperinsulinemia acutely increases serum macrophage inhibitory cytokine-1 concentration in anorexia nervosa and obesity

CONTEXT

Macrophage inhibitory cytokine-1 (MIC-1) plays a role in the regulation of cellular responses to stress signals and inflammation. MIC-1 has also been implicated in mediation of tumour-induced anorexia and weight loss. Increased serum concentrations of MIC-1 were found in patients with anorexia nervosa (AN), obesity and type 2 diabetes.

OBJECTIVE

To estimate serum MIC-1 concentration in women with AN and obese women, its regulation by hyperinsulinemia and relationship with insulin sensitivity.

PATIENTS

We examined 20 women with AN, 28 healthy normal-weight female controls and 28 obese women.

MEASUREMENTS

Serum MIC-1 concentration was measured in the fasting state and after 2-h euglycemic hyperinsulinemic clamp.

RESULTS

At baseline, serum MIC-1 was higher in AN in comparison with other groups (normal-weight, P = 0·018; obese, P = 0·01). Hyperinsulinemia resulted in a significant increase in serum MIC-1 concentration in the entire study population (P < 0·001) and in AN (P < 0·001), normal-weight (P = 0·002) and obese (P < 0·001) groups analysed separately. Postclamp serum MIC-1 was still higher in AN women in comparison with other groups (normal-weight, P = 0·012; obese, P = 0·023). When normal-weight and obese women were analysed together, with the exclusion of AN group, an inverse correlation between insulin sensitivity and the change in serum MIC-1 during the clamp was observed (r = -0·27, P = 0·042).

CONCLUSIONS

Hyperinsulinemia resulted in a significant increase in serum MIC-1 in different states of adiposity. Increased serum MIC-1 in AN women might be an additional factor responsible for weight loss in this group.

Retinol-binding protein 4 in adipose and placental tissue of women with gestational diabetes

In the present study, we evaluated serum levels of retinol-binding protein 4 (RBP4) and the expression of RBP4, glucose transporter-4 (GLUT4) and peroxisome proliferator activated receptor gamma (PPARγ) mRNA (using quantitative real time-PCR) in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and placental tissue obtained from patients with gestational diabetes (GDM) and healthy pregnant women. Serum RBP4 concentrations and its expression in SAT were higher in the women with GDM than in the controls (p = 0.03). No association between serum or tissue RBP4 and the indices of insulin resistance was noted. In the GDM group serum RBP4 correlated with its mRNA expression in SAT (r = 0.67, p = 0.007). Stepwise regression analysis revealed that RBP4 mRNA expression in SAT was independently predicted by GLUT4 mRNA expression (β= 0.59, p = 0.003) and the presence of GDM (β=0.46, p = 0.01), whereas RBP4 mRNA expression in VAT was related to PPARγ mRNA expression (β= 0.64, p = 0.0003) and the patient's age (β= -0.38, p = 0.03). In conclusion, our results suggest that the elevated expression of RBP4 in SAT may contribute to the increase in circulating RBP4 in GDM subjects.

The expression of transcription factor 7-like 2 (TCF7L2) in fat and placental tissue from women with gestational diabetes

In the present study we showed that the expression of transcription factor 7-like 2 (TCF7L2) mRNA in visceral adipose tissue obtained from 20 women with gestational diabetes was lower than in 18 pregnant women with normal glucose tolerance (p = 0.02), however after adjusting for BMI values, the difference was not significant.

Estrogens modulate RANKL-RANK/osteoprotegerin mediated interleukin-6 effect on thyrotoxicosis-related bone turnover in mice

Interleukin-6 has been shown to cause imbalance between bone resorption and formation in thyrotoxicosis. The aim of the present study was an attempt to estimate the influence of estrogens on thyrotoxicosis-related disturbances in bone turnover in relation to RANKL-RANK/osteoprotegerin system in IL-6 deficient mice. The study was performed on 56, 12-13 weeks old, female mice: C57BL/6J (wild-type; WT) and C57BL/6J (IL6-/-Kopf) (IL-6 knock-out; IL6KO). The mice were randomly divided into 8 groups with 7 mice in each one: 1. WT controls, 2. IL6KO controls, 3. WT mice with thyrotoxicosis, 4. IL6KO mice with thyrotoxicosis, 5. WT ovariectomized, 6. IL6KO ovariectomized, 7. WT ovariectomized mice with thyrotoxicosis, and 8. IL6KO ovariectomized mice with thyrotoxicosis. Experimental model of menopause was evoked by bilateral ovariectomy carried out in 8-9 weeks old mice. Thyrotoxicosis was induced by intraperitoneal injection of levothyroxine at a dose of 1 μg/g daily over 21 days. The serum levels of TRACP5b, osteocalcin, OPG, and RANKL were determined by ELISA. RANKL serum concentrations were elevated significantly in all groups of ovariectomized mice as compared to respective controls, however, in a minor degree in IL6KO thyrotoxic mice as compared to wild-type animals. Osteoprotegerin serum levels were significantly increased in all thyrotoxic groups of mice except ovariectomized IL6KO animals. To sum up, the results of the present study suggest that IL-6 plays a key role in stimulation of RANKL-RANK/OPG system and this effect is strongly enhanced in conditions of accelerated bone turnover such as thyrotoxicosis and/or estrogen depletion.

Interleukin-6 and its considerable role in the pathogenesis of thyrotoxicosis-related disturbances of bone turnover in postmenopausal women

BACKGROUND

Thyrotoxicosis is more frequent in postmenopausal women than in the general population, effectively accelerating bone turnover. Interleukin-6 has been shown to be involved in the pathogenesis of bone disorders. Thus, the aim of the present study was to assess the role of IL-6 and its soluble receptor in the pathogenesis of thyrotoxicosis-related disturbances of bone turnover in oestrogen-deficient women.

MATERIAL AND METHODS

The study was carried out in 40 subjects with toxic nodular goitre in three groups: Group 1 - 13 premenopausal females, mean age 36 ± 15 years (PremTx→PremEu); Group 2 - 12 postmenopausal females, mean age 66 ± 14 years (PostTx→PostEu); and Group 3 - 15 males, mean age 45 ± 21 years (MTx→MEu). Overt thyrotoxicosis and euthyreosis after treatment with thyrostatics were confirmed by thyrotropin, free thyroxine and free triiodothyronin concentrations. Serum levels of bone turnover markers: TRACP5b and osteocalcin as well as serum IL-6 and IL-6sR were determined using ELISA kits.

RESULTS

TRACP5b/osteocalcin quotient was significantly elevated in the PostTx females compared to the PremTx women (p < 0.02). There was a positive correlation between serum TRACP5b and osteocalcin in the studied patients (R = 0.45, p < 0.001). Levels of serum IL-6 values were significantly elevated in PostTx: 3.0 (2.14-6.40) and MTx: 2.24 (1.60-5.10), compared to PremTx females: 1.39 (0.96-2.14) (p < 0.01 and p < 0.05 respectively). There were significant positive correlations between IL-6 and IL-6sR concentrations (R = 0.22, p < 0.05) and between IL-6sR and TRACP5b serum levels (R = 0.23, p < 0.05).

CONCLUSIONS

The results of our study suggest that interleukin-6 plays a considerable role in the pathogenesis of thyrotoxicosis-related disturbances of bone turnover in oestrogen-deficient women.

Serum soluble glycoprotein 130 concentration is inversely related to insulin sensitivity in women with polycystic ovary syndrome

OBJECTIVE

Insulin resistance might play a role in the pathogenesis of polycystic ovarian syndrome (PCOS). The family of glycoprotein 130 (gp130) cytokines could influence insulin action. One of these cytokines is interleukin (IL)-6, which exerts a short-term insulin-sensitizing effect, whereas in a long-term period, it might induce insulin resistance. Some other gp130 activators are supposed to have beneficial metabolic effects. Gp130 is present in the circulation in the soluble form (sgp130), which inhibits intracellular gp130 signaling. The aim of the present study was to estimate the relation between sgp130 and insulin sensitivity in women with PCOS.

RESEARCH DESIGN AND METHODS

We studied 78 women with PCOS (35 lean and 43 obese) and 34 healthy women (18 lean and 16 obese). The euglycemic-hyperinsulinemic clamp and the measurements of serum sgp130, IL-6, soluble IL-6 receptor (sIL-6R), and sex hormones were performed.

RESULTS

Both obesity and PCOS were characterized by an increased sgp130 (P < 0.0001 and P = 0.0002, respectively). sIL-6R concentration was lower (P = 0.0036) in women with PCOS independently of obesity. Serum sgp130 was negatively correlated with insulin sensitivity when control and PCOS women were analyzed together (r = -0.36, P < 0.0001) and in the PCOS subjects separately (r = -0.34, P = 0.002). In multiple regression analysis, this correlation was significant after adjustment for BMI, waist, percent of body fat, postload glucose and insulin, triglycerides, and high-sensitive C-reactive protein.

CONCLUSIONS

Serum sgp130 is inversely and independently associated with insulin sensitivity in women with PCOS. An increased serum sgp130 in obesity and PCOS suggests an inhibition of intracellular gp130 signaling in insulin-resistant conditions.

Transcription factor 7-like 2-gene polymorphism is related to fasting C peptide in latent autoimmune diabetes in adults (LADA)

Common polymorphisms in the transcription factor 7-like 2 gene (TCF7L2) have been associated with type 2 diabetes in different populations and recently with LADA, but not with type 1 diabetes. The aim of our study was to investigate association between the rs7903146 polymorphism in the TCF7L2 gene and LADA in Polish patients. Link between the "high risk for type 2 diabetes genotype" with clinical features was analyzed. 68 newly diagnosed patients with LADA and 195 healthy controls were genotyped for the rs7903146 polymorphism in the TCF7L2 gene using the PCR-based RFLP method. Fasting C peptide level was measured by ELISA. We observed increased frequencies of the TT genotype of the rs7903146 polymorphism in the TCF7L2 gene in LADA patients compared to controls (15 vs. 6%, P = 0.03). Fasting C peptide serum concentration was significantly lower in group of patients with LADA carrying the TT genotype (P < 0.01). In conclusion, the data from this study confirmed previous results showing genetic similarities between patients with LADA and type 2 diabetes. Non-autoimmune mechanism may be related to beta cell dysfunction in patients with LADA.

Ghrelin in gestational diabetes: serum level and mRNA expression in fat and placental tissue

OBJECTIVES

We studied the effect of an oral glucose load on circulating ghrelin, as well as ghrelin and ghrelin receptor (GHS-R1a) mRNA expression in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and placental tissue from pregnant women with gestational diabetes (GDM) and normal glucose tolerance (NGT).

METHODS

Plasma total ghrelin levels were measured in 58 patients with GDM and 61 women with NGT by radioimmunoassay. Ghrelin and GHS-R1a mRNA expression was studied in 16 subjects with GDM and 20 healthy pregnant women at term, using RT-PCR.

RESULTS

Basal ghrelin concentrations and the maximal decrease in ghrelin levels after glucose load did not differ in the women with GDM and NGT (399.1 [299.6-563.3] pg/ml vs. 400.9 [302.3-475.8] pg/ml and 127.6 [23.1-213.1] pg/ml vs. 101.7 [44.0-217.6] pg/ml, respectively). Ghrelin mRNA expression in placental tissue was significantly higher in the subjects with GDM than in the healthy pregnant women (0.06 [0.03-0.07] AU vs. 0.02 [0.015-0.03 AU], p=0.02), whereas GHS-R1a mRNA expression in all three tissues studied did not differ between the two groups. Multiple regression analysis revealed that ghrelin mRNA expression in SAT was significantly predicted by serum insulin (beta=0.62, p=0.01), explaining 42% of its variability.

CONCLUSIONS

Ghrelin mRNA expression in placental tissue was higher in the GDM than in NGT subjects, whereas no association between circulating ghrelin and GDM was observed.

Plasma apelin levels and apelin/APJ mRNA expression in patients with gestational diabetes mellitus

AIMS AND METHODS

Apelin is a novel adipokine identified as an endogenous ligand of the G protein-coupled receptor APJ. In this study we compared plasma apelin concentrations in 101 patients with gestational diabetes (GDM) and 101 women with normal glucose tolerance (NGT) between 24 and 32 weeks of gestation (Group 1), as well as in 20 women with GDM and 16 subjects with NGT at term (Group 2). Apelin and APJ mRNA expression in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and placental tissue were also measured in Group 2, using quantitative real-time PCR.

RESULTS

There were no significant differences in plasma apelin levels between the women with GDM and NGT (Group 1: 1555.6 [1281.2-1804.2]pg/ml vs 1656.5 [1430.2-1852.1]pg/ml, Group 2: 1607.9 [1453.4-1768.7]pg/ml vs 1493.8 [1316.8-1956.7]pg/ml) nor in apelin and APJ mRNA expression in SAT, VAT and placental tissue. Apelin mRNA expression was approximately 10 fold higher in placental than in adipose tissue (p<0.0001). Apelin and APJ mRNA expression correlated significantly in SAT (R=0.45, p=0.03), VAT (R=0.69, p=0.003) and placental tissue (R=0.37, p=0.03).

CONCLUSIONS

No associations between circulating apelin or apelin/APJ mRNA expression and GDM or the indices of insulin resistance were noted in our study.

Circulating asymmetric dimethylarginine, endothelin-1 and cell adhesion molecules in women with gestational diabetes

We measured plasma concentrations of asymmetric dimethylarginine (ADMA), endothelin-1 (ET-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin in 56 patients with gestational diabetes (GDM), 68 pregnant women with normal glucose tolerance (NGT) and 36 healthy non-pregnant women. ADMA concentrations were markedly lower in NGT [0.48 (0.42-0.55) micromol/l] than in GDM subjects [0.50 (0.43-0.67) micromol/l] and healthy controls [0.57 (0.46-0.72) micromol/l, P = 0.005]. ET-1 levels were comparable between GDM [0.76 (0.58-0.90) pg/ml] and NGT women [0.75 (0.63-0.92) pg/ml] and significantly higher than in the non-pregnant subjects [0.62 (0.52-0.72) pg/ml, P = 0.007 and P = 0.005, respectively]. There were no differences in sVCAM-1 and E-selectin levels between the groups studied. ADMA levels were significantly associated with fasting glucose (beta = 0.23, P = 0.02) and gestational age (beta = 0.24, P = 0.01). Our results suggest that physiological adaptation to pregnancy is associated with a fall in circulating ADMA and an elevation of ET-1 concentrations, irrespective of the disturbances of glucose tolerance.

The FTO gene modifies weight, fat mass and insulin sensitivity in women with polycystic ovary syndrome, where its role may be larger than in other phenotypes

AIM

Genome-wide association studies have shown that variation in the FTO gene predisposes to obesity and related traits that are common features of polycystic ovary syndrome (PCOS). The aim of the present study was to assess the effect of FTO variation on obesity, insulin sensitivity, and metabolic and hormonal profiles in PCOS.

METHODS

We examined 136 PCOS women (mean body mass index [BMI]: 28.28+/-6.95kg/m(2), mean age: 25.36+/-5.48 years). Anthropometric measurement, euglycaemic-hyperinsulinaemic clamp and oral glucose tolerance tests and sex hormone assessments were performed. The study group was genotyped for the FTO rs9939609 polymorphism.

RESULTS

BMI (29.0+/-6.9kg/m(2) vs 26.1+/-6.8kg/m(2); P=0.023), body weight (80.1+/-20.7kg vs 72.6+/-20.2kg; P=0.048), fat mass (29.7+/-1 6.6kg vs 24.6+/-17.7kg; P=0.045) and waist circumference (89.8+/-16.7cm vs 83.2+/-17.1cm; P=0.028) were higher in carriers of at least one copy of the A allele. Differences in these parameters were more significant when comparing AA and TT homozygotes. Women with the AA genotype also had decreased insulin sensitivity (P=0.025) and follicle-stimulating hormone (P=0.036). In logistic-regression analyses, the association of the FTO gene polymorphism with insulin sensitivity was no longer significant when BMI was included in the model.

CONCLUSION

Variation in the FTO gene modifies weight, adiposity and other measures of obesity and insulin sensitivity in PCOS. The examined FTO gene variant appears to have a greater impact on obesity and related traits in PCOS than in other phenotypes. The effect on insulin sensitivity appears to be secondary to its influence on obesity and body fat.

Lifetime measurements of the neutron-rich N = 30 isotones 50Ca and 51Sc: orbital dependence of effective charges in the fp shell

The lifetimes of the first excited states of the N = 30 isotones (50)Ca and (51)Sc have been determined using the Recoil Distance Doppler Shift method in combination with the CLARA-PRISMA spectrometers. This is the first time such a method is applied to measure lifetimes of neutron-rich nuclei populated via a multinucleon transfer reaction. This extends the lifetime knowledge beyond the f_{7/2} shell closure and allows us to derive the effective proton and neutron charges in the fp shell near the doubly magic nucleus (48)Ca, using large-scale, shell-model calculations. These results indicate an orbital dependence of the core polarization along the fp shell.

Visfatin in gestational diabetes: serum level and mRNA expression in fat and placental tissue

AIMS AND METHODS

In this study we measured: (1) serum visfatin concentrations in pregnant women with normal glucose tolerance (NGT) and gestational diabetes mellitus (GDM) between 26 and 33 weeks of gestation, using two immunoassays: EIA and ELISA; (2) serum visfatin levels (ELISA) and its mRNA expression (quantitative real-time PCR) in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and placental tissue from women with NGT and GDM at term.

RESULTS

Visfatin concentrations (measured by EIA and ELISA) did not differ in the women with GDM and NGT between 26 and 33 weeks of gestation but were significantly lower in GDM than in NGT subjects at term (2.7 [0.7-4.6] vs 5.2 [3.7-5.9]ng/ml, p=0.02). There was no difference in visfatin mRNA expression in fat and placental tissue between the two subgroups. Regression analysis revealed that visfatin mRNA expression was significantly related to interleukin-6 and tumour necrosis factor-alpha mRNA expression in SAT (beta=0.39, p=0.009 and beta=0.47, p=0.002) and placental tissue (beta=0.37, p=0.03 and beta=0.49, p=0.005).

CONCLUSIONS

Circulating visfatin was significantly lower in the GDM than in the NGT subjects at term, although no differences in its mRNA expression in fat and placental tissues were observed.

High resistin and interleukin-6 levels are associated with gestational diabetes mellitus

Resistin is a cysteine-rich adipokine originally described as a molecular link between obesity and insulin resistance in rodents. In this study, we hypothesised that serum resistin concentrations are elevated in patients with gestational diabetes mellitus (GDM) when compared with pregnant women with normal glucose tolerance (NGT) and related to proinflammatory interleukin-6 (IL-6) and other factors conferring insulin resistance. Serum resistin and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA) in 81 women with GDM, 82 women with NGT between 24 and 31 weeks of gestation and 25 healthy non-pregnant women. Resistin concentrations were significantly higher in the GDM (21.9 [17.55-25.40] ng/ml) than in the NGT group (19.03 [15.92-23.91] ng/ml, p = 0.047), as well as in the non-pregnant women (14.8 [13.7-16.6] ng/ml, p < 0.0001). Serum IL-6 levels were elevated in the GDM (1.0 [0.7-1.5] pg/ml) as compared with the NGT group (0.8 [0.5-1.1] pg/ml, p = 0.006) and the non-pregnant controls (0.7 [0.5-1.1] pg/ml, p = 0.04). Multiple regression analysis revealed that in the pregnant women circulating resistin was related to serum IL-6 (beta = 0.33, p = 0.0004) but not to insulin or the index of insulin resistance. It is concluded that the finding of high resistin and IL-6 levels in women with gestational diabetes might confirm a role of low-grade inflammation in the pathogenesis of GDM.

Search for the pygmy dipole resonance in 68Ni at 600 MeV/nucleon

The gamma decay from Coulomb excitation of 68Ni at 600 MeV/nucleon on a Au target was measured using the RISING setup at the fragment separator of GSI. The 68Ni beam was produced by a fragmentation reaction of 86Kr at 900 MeV/nucleon on a 9Be target and selected by the fragment separator. The gamma rays produced at the Au target were measured with HPGe detectors at forward angles and with BaF2 scintillators at backward angles. The measured spectra show a peak centered at approximately 11 MeV, whose intensity can be explained in terms of an enhanced strength of the dipole response function (pygmy resonance). Such pygmy structure has been predicted in this unstable neutron-rich nucleus by theory.

Insulin resistance, serum adiponectin, and proinflammatory markers in young subjects with the metabolic syndrome

Insulin resistance is the underlying metabolic abnormality in the metabolic syndrome. The low-grade chronic inflammation may be associated with metabolic risk factors and atherogenesis. The aim of our study was to establish the link between the metabolic syndrome, as defined by the National Cholesterol Education Program (NCEP) criteria, and insulin sensitivity, serum adiponectin, and parameters of chronic inflammation in young subjects. The group of 223 subjects (mean age, 25.86 +/- 5.49 years; body mass index, 28.04 +/- 6.91 kg/m2) was studied. Oral glucose tolerance test, euglycemic hyperinsulinemic clamp, and estimation of serum adiponectin and proinflammatory factors were performed. The NCEP-defined metabolic syndrome was present in 49 subjects (21.97%). The higher the number of NCEP criteria fulfilled was, the bigger were the decrease in insulin sensitivity (P < .0001) and adiponectin (P < .0001) and the increase in fasting and postload insulin (both Ps < .0001), C-reactive protein (P < .0001), interleukin 18 (P < .0001), interleukin 6 (P < .0001), and soluble tumor necrosis factor-alpha receptors sTNFR1 (P < .0001) and sTNFR2 (P < .0001) observed. Multiple regression analysis revealed that adiponectin and inflammatory factors predicted NCEP score independent of insulin sensitivity (all adjusted beta values between .16 and .32, all Ps < .01). Young subjects with metabolic syndrome demonstrate an increased inflammatory response and lower adiponectin concentration.

Circulating pro- and anti-inflammatory cytokines in Polish women with gestational diabetes

In this study we measured serum concentrations of proinflammatory interleukin-6, interleukin-8, and interleukin-18 as well as anti-inflammatory interleukin-10 in 30 pregnant women with normal glucose tolerance, in 32 women with abnormal results of a 50-g glucose challenge test, and in 57 patients with gestational diabetes mellitus. Patients with gestational diabetes had significantly higher IL-6 (median 1.0 [0.7-1.5] vs. 0.7 [0.4-0.8] pg/ml, p=0.001), IL-8 (2.1 [1.1-4.2] pg/ml vs. 0.7 [0.4-0.9] pg/ml, p<0.0001), and IL-18 (249.3 [188.5-318.7] pg/ml vs. 186.7 [139.9-243.9] pg/ml, p=0.005) as well as lower IL-10 levels than healthy pregnant women (0.6 [0.5-1.5] pg/ml vs. 2.9 [1.8-3.2] pg/ml, p<0.0001). After adjusting for glucose, insulin, and BMI values, the differences in IL-8 and IL-18 became insignificant, whereas the differences in IL-6 and IL-10 levels remained highly significant (p<0.0001). The subjects with abnormal glucose challenge test results had higher IL-6 levels (0.9 [0.7-1.3] pg/ml, p=0.005) and similar levels of other cytokines as compared with the women with normal glucose tolerance. Our results suggest an impaired balance between circulating pro- and anti-inflammatory cytokines in patients with gestational diabetes; however, a significant contribution of maternal obesity to the increased levels of IL-8 and IL-18 should be underlined.