Aleksandar Djukic

Galectin-3 Deficiency Accelerates High-Fat Diet Induced Obesity and Amplifies Inflammation in Adipose Tissue and Pancreatic Islets

Obesity-induced diabetes is associated with low-grade inflammation in adipose tissue and macrophage infiltration of islets. We show that ablation of galectin-3 (Gal-3), a galactoside-binding lectin, accelerates high-fat diet–induced obesity and diabetes. Obese LGALS3−/− mice have increased body weight, amount of total visceral adipose tissue (VAT), fasting blood glucose and insulin levels, homeostasis model assessment of insulin resistance, and markers of systemic inflammation compared with diet-matched wild-type (WT) animals. VAT of obese LGALS3−/− mice exhibited increased incidence of type 1 T and NKT lymphocytes and proinflammatory CD11c+CD11b+ macrophages and decreased CD4+CD25+FoxP3+ regulatory T cells and M2 macrophages. Pronounced mononuclear cell infiltrate, increased expression of NLRP3 inflammasome and interleukin-1β (IL-1β) in macrophages, and increased accumulation of advanced glycation end products (AGEs) and receptor for AGE (RAGE) expression were present in pancreatic islets of obese LGALS3−/− animals accompanied with elevated phosphorylated nuclear factor-κB (NF-κB) p65 and mature caspase-1 protein expression in pancreatic tissue and VAT. In vitro stimulation of LGALS3−/− peritoneal macrophages with lipopolysaccharide (LPS) and saturated fatty acid palmitate caused increased caspase-1–dependent IL-1β production and increased phosphorylation of NF-κB p65 compared with WT cells. Transfection of LGALS3−/− macrophages with NLRP3 small interfering RNA attenuated IL-1β production in response to palmitate and LPS plus palmitate. Obtained results suggest important protective roles for Gal-3 in obesity-induced inflammation and diabetes.

Comparison of the influence of thyroglobulin antibodies on serum thyroglobulin values from two different immunoassays in post surgical differentiated thyroid carcinoma patients

Measurement of serum thyroglobulin (Tg) is a highly specific test in the management of patients with differentiated thyroid cancer (DTC) after surgical treatment. The aim of our study was to evaluate and compare Tg levels in these patients found by radioimmunoassay (RIA) and immunoradiometric assay (IRMA) and to assess the influence of Tg antibodies (TgAbs) on the values obtained for Tg concentration. Both Tg and TgAb were determined postoperatively in the serum of 71 DTC patients using RIA Tg‐PEG (INEP) and Tg IRMA (CIS) for Tg, together with TgAb (CIS) for circulating endogenous anti‐TgAbs. The obtained concentrations were evaluated statistically. We found a significant difference of Tg concentrations between paired samples from the IRMA and RIA, although the intermethod comparison yielded satisfactory concordance of the twoassays (Spearman correlation coefficient −0.792). Positive TgAb was found in 28.2% of the serum samples analyzed. Spearman rank correlation analysis revealed a significant negative relationship between serum TgAb and Tg level measured by IRMA (P=0.02), but not by RIA (P=0.417). On the other hand, our clinical data revealed that 1/18 and 3/18 patients with proven lymph node metastasis had Tg values below the detection limit by RIA and IRMA assay, respectively. Their sera were TgAb positive. We concluded that RIA was less prone to influence of TgAb than IRMA. As the presence of TgAbs may interfere in Tg measurement irrespective of the method selected for determination, this should be considered during the clinical management of these patients. J. Clin. Lab. Anal. 23:341–346, 2009.

Intravenous immunoglobulins exposed to heme (heme IVIG) are more efficient than IVIG in attenuating autoimmune diabetes

Intravenous immunoglobulins (IVIG) are known to have a therapeutic effect in some autoimmune diseases. We examined the effect of IVIG and heme-exposed IVIG on the development of immune mediated diabetes induced in C57BL/6 mice by multiple low doses of streptozotocin. IVIG were used in a dose of 200mg/kg daily for 15 days. Treatment with IVIG resulted in significant attenuation of diabetes induction as evaluated by glycemia, glycosuria and HbA1c level. Interestingly, heme-exposed IVIG had a still stronger antidiabetogenic effect. Serum levels of proinflammatory cytokines TNF-α, IFN-γ and IL17 were lower in IVIG treated animals when compared with controls, while IL10 level was higher. The number of CD4(+)Foxp3(+) cells was higher in pancreatic lymph nodes of heme-exposed IVIG treated mice. Our results show that IVIG may downregulate diabetes induction possibly by favouring induction of T regulatory cells and suggest enhanced effect upon heme-binding to IVIG.

Galectin-3 is a regulator of metaflammation in adipose tissue and pancreatic islets

The cells of the innate and adaptive immune systems have been implicated in the development of obesity-induced metaflammation and metabolic disorders including type 2 diabetes. Galectin-3, a β-galactoside-binding lectin, modulates immune/inflammatory responses and specifically binds to advanced glycation end products (AGE), modified lipoproteins, and endotoxin. In the recently published study we demonstrate proinflammatory changes in the visceral adipose tissue and pancreatic islets in galectin-3-deficient mice fed high-fat diet which also exhibited excess adiposity, hyperglycemia, insulin resistance and systemic inflammation compared with their diet matched wild-type controls. This was associated with the increased incidence of Type-1 T and NKT cells and pro-inflammatory CD11c+CD11b+ macrophages in the visceral adipose tissue. Severe insulitis, infiltration of macrophages expressing NLRP3 inflammasome and IL-1β, and enhanced accumulation of AGE were present within the pancreatic islets in obese LGALS3−/− mice. Moreover, increased caspase-1 dependent IL-1β secretion with increased expression of NLRP3 inflammasome and phospho-NFκBp65 were observed in LGALS3−/− peritoneal macrophages stimulated in vitro by lipopolysaccharide and/or saturated fatty acid palmitate. The amplified high-fat diet-induced obesity and hyperglycemia and exacerbated inflammation in adipose tissue and pancreatic islets in LGALS3−/− mice suggest an important role for galectin-3 in the regulation of adiposity, metaflammation and type 2 diabetes.

NT-proBNP for prognostic and diagnostic evaluation in patients with acute coronary syndromes

BACKGROUND AND AIM N terminal-proB-type natriuretic peptide (NT-proBNP) is synthesised and secreted from the ventricular myocardium. This marker is known to be elevated in patients with acute coronary syndromes (ACS). We evaluated NT-proBNP asa significant diagnostic marker and an important independent predictor of short-term mortality (one month) in patients with ACS. METHODS NT-proBNP and cardiac troponin I (cTI) were assessed in 134 consecutive patients (median age 66 years, 73% male)hospitalised for ACS in a cardiological university department. The patients were classified into ST-elevation ACS (STE-ACS, n = 74) and non-ST-elevation ACS (NSTE-ACS, n = 60) groups based on the ECG findings on admission. Patients with Killip class ≥ II were excluded. RESULTS The serum level of NT-proBNP on admission was significantly higher (p < 0.0005), while there was no difference in cTI serum level in the NSTE-ACS patients compared to STE-ACS patients. There was a significant positive correlation between NT-proBNP and cTI in the NSTE-ACS (r = 0.338, p = 0.008) and STE-ACS (r = 0.441, p < 0.0005) patients. There was a significant difference in NT-proBNP (p < 0.0005) and cTI (p < 0.0005) serum level between ACS patients who died within 30 days or who survived after one month. The increased NT-proBNP level is the strongest predictor of mortality in ACS patients, also NT-proBNP cut-point level of 1,490 pg/mL is a significant independent predictor of mortality. CONCLUSIONS We demonstrated the differences and the correlation in the secretion of NT-proBNP and cTI in patients with STE-ACS vs. NSTE-ACS. Our results provide evidence that NT-proBNP is a significant diagnostic marker and an important independent predictor of short-term mortality in patients with ACS.

Effect of biphasic insulin aspart on glucose and lipid control in patients with Type 2 diabetes mellitus

Objective: this study examined the efficacy and safety of biphasic insulin aspart 30 (BIAsp 30) monotherapy in insulin-naive patients with Type 2 diabetes mellitus. Research design and methods: in this 12-week, open-labelled, uncontrolled, clinical-experience study involving 71 patients with secondary oral antidiabetic agent failure, patients received BIAsp 30 after discontinuing oral antidiabetic drugs (OADs). Glucose and lipid concentrations, hypoglycaemic episodes and adverse events were assessed before and after treatment. Patient data were categorised according to previous OADs into the biguanides (BI) plus sulfonylureas/meglitinides (SU/MEG) and SU-only groups. Results: after treatment, glucose and lipid control was significantly improved in both groups, with a greater improvement in the SU-only group. Mean glycated haemoglobin, fasting blood glucose and postprandial blood glucose excursion improved by 2.15 ± 1.24%, 3.70 ± 3.18 mmol/l and 1.26 ± 2.65 mmol/l in the BI plus SU/MEG group, and by 3.09 ± 1.62%, 6.11 ± 5.02 mmol/l and 2.06 ± 2.33 mmol/l in the SU-only group, respectively. Mean high-density lipoprotein cholesterol and triglycerides improved by 0.09 ± 0.18 mmol/l and 0.94 ± 1.17 mmol/l in the BI plus SU/MEG group and by 0.09 ± 0.18 mmol/l and 1.04 ± 2.72 mmol/l in the SU-only group, respectively. No major hypoglycaemic episodes or serious treatment-related adverse events were reported. Conclusions: our study showed that BIAsp 30 treatment safely improved glucose and lipid control in insulin-naive patients with Type 2 diabetes poorly controlled on BI plus SU/MEG and SU-only. Key limitations were the lack of a comparator group and the short study duration.

Phagocytic activity and nitric oxide production of circulating polymorphonuclear leukocytes from patients with peritoneal carcinomatosis

Many studies have demonstrated an increase of neutrophils in patients with advanced cancer. However, the possible role of increased neutrophils in various neoplasms studied to date varies considerably. The authors examined the changes in white blood cell counts in patients with peritoneal carcinomatosis. Malonildialdehyde and nitric oxide (NO) plasma and ascitic fluid levels, phagocitic activity and the ability of the polymorphonuclear cells (PMNCs) to produce nitric oxide were also measured. An increase in PMNCs and decrease in lymphocytes was found in cancer patients. Compared with healthy controls, cancer PMNCs showed significant enhancement of phagocytosis. Similarly, pretreatment of healthy PMNCs with crude supernatants from short-term cultures of the peritoneal cells from ascitic fluid of patients with peritoneal carcinomatosis caused marked stimulation of PMNC phagocytosis. In addition, plasma and ascitic fluid nitric oxide levels in cancer patients were significantly higher than those found in control one. Most importantly, it was found that PMNCs from cancer patients release significantly more nitric oxide than corresponding normal controls. Therefore, considering the fact that neutrophils make up more than 50% of total leukocytes, these cells can play one of the most important roles in tumor biology.

GLYCOREGULATION DURING PREGNANCY

Abstract Pregnancy is a period marked by profound changes in a woman’s hormonal status and metabolism, including the development of a carbohydrate-intolerant state. Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. The aim of this study was to estimate and analyse the parameters of glycaemic control during pregnancy. We stratified patients into the following three groups according to OGTT results: normal glucose tolerance (NTG), gestational impaired glucose tolerance (GIGT) and GDM. We investigated 92 pregnant women, diagnosed with vital and desired pregnancy up to 12 weeks of gestation, who had signed informed consent forms. Among them, 7 pregnant women had a spontaneous abortion, while 8 pregnant women dropped out, so a total of 77 pregnant women completed the trial. Most of the women examined had no risk factors (48%), while 35% of the women had one risk factor. The current study demonstrates that normal glucose tolerance was shown in 59 (76.6%) participants, while some form of glucose intolerance (GIGT or GDM) was shown in 18 (23.4%) patients. Our findings revealed an increase in glucose intolerance with advancing pregnancy (in the second and third trimester). In conclusion, we demonstrate that the difference in the quality of glycaemic control during pregnancy is manifested in the second and third trimester, until it manifests in the first trimester. These findings underpin the clinical significance of discovering GDM.

Population pharmacokinetics of 25-hydroxyvitamin D in healthy young adults.

OBJECTIVES The aim of our study was to develop a population pharmacokinetic (PPK) model for 25-hydroxyvitamin D clearance in a healthy young adult population in Serbia. METHODS Study sample consisted of 70 healthy young students of the Faculty of Medical Science, University of Kragujevac, Serbia, with a mean age and body mass index of 22.39 ± 1.82 years and 21.31 ± 2.69 kgm-2, respectively. Non-linear mixed-effect modeling (NONMEM) software was used for data analysis. A validation set of 16 participants was used to estimate the predictive performance of the pharmacokinetic model. RESULTS In the base model (without covariates), we had parameter estimates of 0.01 L/h for apparent clearance, 0.25 L for apparent volume of distribution, while value of minimum objective function (MOF) was 383.468. The full regression model was established by estimating the effects of 12 covariates. Mean intake of vitamin D from foods (DD) and value of phosphate in serum (PHO) were covariates included in the final model, while others were excluded in this process. The estimated value in the final MOF model was 274.555. The final regression model formula was: clearance (CL) (L/h) = 0.0711 + 0.738 x DD + 0.618 x PHO. CONCLUSIONS The PPK model obtained determined clearance of 25-hydroxyvitamin D in a healthy young adult population in Serbia. Mean intake of vitamin D from foods and serum phosphate level are the most important covariates that influence value of 25-hydroxyvitamin D clearance in healthy young adults.

Generalized eruptive xanthomas associated with diabetic dyslipidemia

A 39-year-old, obese male, (body mass index 41.3 kg/m2) presented to the Department of Dermatology with generalized, diffuse, pruritic skin lesions. According to the patient, the first skin lesions had begun to appear a few years before, on the extensor side of the elbows and shoulders. Two months before dermatological examination, new skin lesions appeared in crops on the trunk and extremities, with a tendency to generalization. Physical examination showed small, generalized, pruritic, yellowish [...]