Biomedical subjects

M Haluzik

Publications and source records attributed to M Haluzik.

3 recordsLinked to original sources

PubMed2000

Serum leptin levels in diabetic patients on hemodialysis: the relationship to parameters of diabetes metabolic control.

Leptin is a protein hormone produced predominantly by adipocytes that affects food intake and energy expenditure. Its serum levels are significantly higher in patients with chronic renal failure compared to healthy subjects. The aim of this study was to compare serum leptin levels in hemodialyzed patients with type II diabetes mellitus (n=26) with body content-matched hemodialyzed patients without diabetes (n=26) and to explore the relationship between parameters of the long term diabetes metabolic control and serum leptin levels. Serum leptin levels in diabetic patients did not significantly differ from those of non-diabetic patients (25.3+/-8.8 vs 25.7+/-8.7 ng/ml). Serum leptin levels in diabetic patients positively correlated with body fat content, body mass index and predialysis serum insulin levels. No significant relationship were observed between serum leptin levels and blood glucose, glycated hemoglobin, glycated protein, serum urea, creatinine, leukocyte count and total hemoglobin respectively. The multiple stepwise regression analysis revealed that body fat content together with body mass index accounted for 77.8% of variations in predialysis serum leptin levels, while insulin levels and the parameters of diabetes metabolic control had only slight prediction value for leptin concentrations. We conclude that serum leptin levels in hemodialysed patients with type III diabetes mellitus do not significantly differ from those of hemodialysed non-diabetic patients. The body fat content and body mass index are the strongest predictors of serum leptin levels, while parameters of long term diabetes metabolic control play probably only minor direct role in its regulation.

Blood Glucose↗

PubMed1999

Treatment with the NO-synthase inhibitor, methylene blue, moderates the decrease in serum leptin concentration in streptozotocin-induced diabetes.

It was previously reported that serum leptin concentrations were decreased in rats with streptozotocin-induced diabetes. Also, simultaneous nitric oxide (NO)-synthase inhibitor treatment is known to partially attenuate streptozotocin-induced diabetes development. The aim of our study was to investigate the influence of the NO-synthase inhibitor, methylene blue, on serum leptin concentration and diabetes development. Body weight, blood glucose, glycated hemoglobin and leptin concentration were measured in a control group, diabetic (streptozotocin 70 mg/kg i.p.) group, methylene blue (40 mg/kg in the food) treated group and a diabetic group treated with methylene blue. After six weeks of experiments, blood glucose and glycated hemoglobin increased significantly in the diabetic group vs controls (27.31 vs 5.49 mmol.l(-1), 14.11 vs 6.79%, respectively) and this increase was partially attenuated by simultaneous methylene blue treatment (16.8 vs 27.31 mmol/l, p < 0.05). Body weight and serum leptin fell in diabetic rats vs controls (248.9 vs 342.8 g, 0.57 vs 3.46 ng.ml(-1)). Treatment with methylene blue significantly suppressed the drop of body weight and the increase in blood glucose and glycated hemoglobin concentrations in the diabetic group. The decrease of serum leptin levels was significantly inhibited by methylene blue in the first experiment (1.1 vs 0.57 ng. ml(-1), p < 0.05); the same trend was found in a second experiment but the differences did not reach statistical significance. We conclude that the drop of serum leptin levels in diabetic rats is probably mainly due to streptozotocin-induced insulin deficiency, which is partially attenuated by NO-synthase inhibitor treatment.

Animals↗

PubMedDate not supplied

The relationship of serum leptin levels and parameters of endurance training status in top sportsmen.

Leptin is a hormone that reflects the body fat content. It was reported that serum leptin levels were decreased in highly endurance-trained sportsmen in comparison with control non-sporting subjects. The aim of our work was to study the relation of serum leptin to blood viscosity and selected spiroergometric parameters of endurance capacity in a group of top rugby players and top race walkers. We have found that both body fat content and serum leptin levels were significantly lower in race walkers than in rugby players (9.68+/-3.65 vs 15.95+/-3.15% and 2.84+/-1.1 vs 3.89+/-1.09 ng x ml(-1) respectively, p<0.05). The positive correlation of serum leptin levels with body fat in both groups. The level of endurance training status was significantly higher in the race walkers group. Serum leptin levels significantly negatively correlated oxygen uptake per body and pulse oxygen per body weight only in rugby players but not in race walkers. Partial correlation test after adjusting for the effect of body fat content showed that leptin itself is not an independent predictor of endurance trainability in this group. Serum leptin levels correlated positively with blood viscosity only in race walkers, but not in the rugby players group. We conclude that serum leptin levels in top sportsmen parallel the changes in body fat content and are not an independent predictor of endurance training of these subjects.

Adipose Tissue↗