Comparison of antihyperglycemic effects of creatine and glibenclamide in type II diabetic patients.

This study compares the effects of glibenclamide and creatine in type II diabetics. In a 14-day symmetrically randomized crossover trial recently detected type II diabetics received either creatine (3 g) or glibenclamide (3.5 mg) for five successive days, followed by two days of washout, and crossover to the opposite treatment.

Comparison of antihyperglycemic effects of creatine and metformin in type II diabetic patients.

Purpose: To compare the antihyperglycemic effects of metformin and creatine in recently detected type II diabetics in a short-term clinical study.

Methods: In a 14 day simmetrically randomized crossover study, recently detected type II diabetics received either creatine (2x3 g/day) or metformin (2x500 mg/day) for five days, followed by two days of washout, followed by cross-over to the opposite treatment for the next five days. Fasting and post-prandial (-15, 60, 90, 120, 180 and 240 min) blood glucose, insulin, c-peptide, creatine and lactate were measured every other day for the duration of treatment, and HbA1c only at the begining and at the end of the study.

Effect of creatine on the pancreatic beta-cell.

We report on the stimulatory effect of creatine on insulin secretion and ATP concentration in MIN-6 beta-cells. The addition of creatine (5 mM) to MIN-6 cells in the presence of glucose (1-10 mM) elicited a significant (p<0.001) increase in insulin secretion, but no effect was demonstrated in the absence of glucose.

The influence of season on oxidant-antioxidant status in trained and sedentary subjects.

The association between oxidative stress and cardiovascular diseases is a widely accepted fact today. Generally, men have a higher risk of cardiovascular incidents and mortality from acute myocardial infarction and strokes. We have examined sport-associated circannual rhythms of oxidant and antioxidant processes by measuring plasma LPO, erythrocyte SOD, CAT, Gpx activity and plasma hormonal status in both sedentary and long-term trained men and women.

Uric acid may inhibit glucose-induced insulin secretion via binding to an essential arginine residue in rat pancreatic beta-cells.

Uric acid (1a) suppresses basal insulin release in isolated rat pancreatic islets and inhibition of glucose-stimulated insulin secretion (GSIS) occurs right at hyperuricaemic levels (0.4 mM). Conversely, 1 mM guanidinium urate (2a) was completely ineffective, strongly suggesting that binding to an essential arginine residue triggers the inhibitory effect.

Beta-cell secretory function and CD25 + lymphocyte subsets in the early stage of type 1 diabetes mellitus.

Cellular immunologic tests have not been used for diagnostic purposes in individuals at risk for autoimmune insulitis or in patients with partial beta-cell destruction because of a lack of studies that show their predictive value. In this study we initially evaluated 43 patients with recent-onset Type 1 diabetes (disease duration View Article and Find Full Text PDF

Enkephalin degradating enzymes in pheochromocytoma patients.

Adrenal gland as a major source of enkephalins on the periphery can be affected by a rare adrenal gland tumor, adrenal pheochromocytoma. It has been demonstrated that this tumor might be associated with altered concentration of enkephalin-like peptides. The effect of these peptides can be either prolonged or abbreviated by two neutrophil membrane bound enzymes; aminopeptidase N (APN) and neutral endopeptidase (NEP).

Effect of creatine on erythrocyte rheology in vitro.

To evaluate how creatine influences erythrocyte deformability, we determined its effect on erythrocyte filterability in 9 subjects with insulin dependent diabetes (IDDM) without complications, 14 diabetics with uremia and 10 non-diabetic controls. The short-term incubation (15 min at 37 degrees C) of diabetic erythrocytes with 3 mM creatine improved cell filterability (assessed according to the Reid method) from IDDM subjects without complications by 28.4% and that from diabetics with uremia by 18.

Semen quality and reproductive endocrine function in relation to biomarkers of lead, cadmium, zinc, and copper in men.

Blood lead (BPb), activity of delta-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP), blood cadmium (BCd), serum zinc (SZn), seminal fluid zinc (SfZn), serum copper (SCu), and parameters of semen quality and of reproductive endocrine function were measured in 149 healthy male industrial workers 20-43 years of age. The group contained 98 subjects with slight to moderate occupational exposure to Pb and 51 reference subjects. All of the subjects lived in Zagreb, Croatia.

Influence of methionine-enkephalin on stress-induced parameters.

This study examines the influence of methionine-enkephalin (MENK) on stress-induced oxidative damage (lipid peroxidation; LPO) in mice liver homogenate, plasma corticosterone concentration (CS) and phagocytic activity of mouse splenocytes. The LPO value increased in the mice subjected to restraint stress and had no correlation to stress duration, while MENK had no effect. The CS concentration was enhanced after 6 h of stress and 6 h after injection of a low (2.

The role of cytokines in MET-enkephalin-modulated nitric oxide release.

In the present study the in vitro and in vivo effect of Met-enkephalin (MENK) on nitric oxide (NO) release by mouse peritoneal macrophages was evaluated. While in vitro MENK was ineffective unless combined with suboptimal concentrations of recombinant murine interferon gamma, in vivo all the doses (2.5, 5 or 10 mg/kg bw) bimodaly modulated NO release.

Superoxide dismutase activity in lymphocytes and polymorphonuclear cells of diabetic patients.

Copper-zinc superoxide dismutase (Cu,Zn-superoxide dismutase) activity was evaluated in lymphocytes and polymorphonuclear cells of insulin-dependent (n = 33) and non-insulin-dependent (n = 34) diabetic patients. A commercial method for the measurement of superoxide dismutase activity was adapted for use on a discrete analyser and evaluated for interference by other antioxidants with superoxide anion-scavenging properties. In comparison to healthy control subjects (n = 32), a significantly lower Cu,Zn-superoxide dismutase activity was found in both lymphocytes and polymorphonuclear cells of insulin-dependent (2.

Total plasma antioxidants in first-degree relatives of patients with insulin-dependent diabetes.

Insulin-dependent diabetes mellitus (IDDM) is a chronic disorder that results from autoimmune destruction of the pancreatic beta-cells. Recent evidence suggests that oxidative damage, resulting from both cytokine-induced production of toxic free radicals and low antioxidant capacity of the beta-cell plays a significant role in the pathogenesis of IDDM. Islet cell antibodies (ICA) have been the best validated marker of risk for the development of IDDM in predisposed individuals, i.

Evaluation of ascorbate and urate antioxidant capacity in human semen.

The ascorbate/urate ratio in the seminal plasma was studied in 76 randomly chosen infertile men. The levels of ascorbate and urate were found to vary widely (range: 93-954 mumol l-1 and 127-670 mumol l-1, respectively), while the ascorbate/urate ratio was 1.03 +/- 0.

Relationship of sperm superoxide dismutase-like activity with other sperm-specific enzymes and experimentally induced lipid peroxidation in infertile men.

Superoxide dismutase-like activity (SOD-like), isoenzyme lactate dehydrogenase-C4 (LDH-C4) and NADH-diaphorase activities in spermatozoa have been investigated from 58 normozoospermic and 27 oligozoospermic men. Significantly higher SOD-like, LDH-C4 and diaphorase activities (P < 0.01, P < 0.

Met-enkephalin modulates stress-induced alterations of the immune response in mice.

Overnight restraint stress of mice decreased ConA-driven lymphocyte proliferation, plaque-forming cell response to sheep red blood cells (SRBC), and NK activity in the spleen, but the phagocytic activity was enhanced. Injection of methionine-enkephalin (MENK), 10 mg/kg, i.p.

Superoxide anion scavenging capacity of human seminal plasma.

This study has investigated the antioxidant capacity of human seminal plasma due to the presence of both high and low molecular weight antioxidant factors. Methods for the measurement of superoxide dismutase-like activity (SOD-like) and total antioxidant status (TAS) were automated, and had a within-run coefficient of variation of 7.3% for SOD-like activity and 4.

Concentration of sialic acid in alloxan diabetic rat islets of Langerhans.

A microanalytical procedure for the determination of total and surface sialic acid concentrations was employed to establish their changes in relation to the length of alloxan diabetes in rat islets of Langerhans. 14 and 60 days after alloxan administration (65 mg/kg), the number of Langerhans islets was significantly decreased (p < 0.001) compared to the control.

Interaction of Met-enkephalin and corticosteroids in immunomodulation.

The effect of Met-enkephalin (MENK) on several immune functions, corticosterone (CS) and adrenocorticotropin (ACTH) levels in the plasma was studied in adrenalectomized (ADX) and sham-adrenalectomized (SADX) mice. Multiple Met-enkephalin injections (10 mg/kg per day in two injections 12 h apart, for 4 days) increased the plaque-forming cell response to sheep erythrocytes in the spleen and enhanced the proliferation of spleen cells in vitro. These effects were comparable in sham-adrenalectomized and adrenalectomized mice.

The effect of guanidino substances from uremic plasma on insulin binding to erythrocyte receptors in uremia.

We have studied insulin binding to erythrocyte receptors in a group of 25 nonobese, nondiabetic uremic patients undergoing maintenance hemodialysis for 2-54 months and 14 healthy controls. Erythrocytes of predialyzed uremics bind significantly less insulin than control erythrocytes (p less than 0.01).