|
|
The use of magnetic resonance spectroscopy for studying glucose metabolism
Kratochvílová, Simona ; Pelikánová, Terezie (advisor) ; Štich, Vladimír (referee) ; Polák, Jan (referee)
Magnetic resonance spectroscopy (MRS) is a noninvasive technique that enables to follow metabolic processes in selected tissues in vivo. Recently the attention has been focused on metabolic mapping in target organs of insulin action to describe the pathophysiology of insulin resistance. The aim of our study was to present the practical application of ³¹P (phosphorus) MRS and ¹H (proton) MRS in metabolic studies of skeletal muscle in insulin resistant subjects and in subjects with impaired fasting glucose. The third study was aimed to evaluate the brain metabolism with ¹H MRS in healthy controls and subjects with type 1 diabetes during hyperinsulinemia. ¹H and ³¹P MRS were performed using a MR Scanner Siemens Vision operating at 1,5 Tesla. To assess the parameters of glucose metabolism and insulin action oral glucose tolerance test and hyperinsulinemic euglycemic clamp were performed. The study 1 was aimed to evaluate the skeletal muscle (m. soleus) energetic metabolism in the offspring of hypertensive parents (OH) with a higher level of insulin resistance. The concentrations of selected high energy phosphates (phosphocreatine, inorganic phosphate, adenosintriphosphate, phosphomonoesters, phosphodiesters) were evaluated with ³¹P MRS. Their amount in OH was comparable to healthy controls. However we...
|
|
|
Insulin resistance and postprandial state in type 2 diabetes. The effect of meal frequency and composition on glucose metabolism and other manifestations of the metabolic syndrome
Thieme, Lenka ; Pelikánová, Terezie (advisor) ; Kunešová, Marie (referee) ; Šmahelová, Alena (referee)
The project focuses on dietary interventions in type 2 diabetes(T2D). The aim was to investigate how glucose metabolism and other manifestations of insulin resistance should be influenced by a) the composition of macronutrients and b) frequency of meals; and to characterize the possible mechanisms of these dietary interventions in patients with T2D. A. In a randomized crossover study, 50 patients T2D and 50 age-matched healthy subjects underwent in a random order meal tolerance tests with three isocaloric meals (vegan sandwich; V-meal, hamburger; M-meal, or cheese sandwich; S-meal. Blood samples for analysis were taken at time 0 and after 30, 60, 120 and 180 minutes after meal ingestion. Plasma concentrations of plasma glucose, insulin, C-peptide, lipids, oxidative stress markers and gastrointestinal hormones (GIHs) were investigated. Both basal and postprandial plasma concentrations of glucose and insulin were significantly higher in patients with T2D (p<0.001); basal and postprandial concentrations of almost all other GIHs (except for ghrelin) and thiobarbituric acid reactive substances (TBARS) were significantly increased (p<0.001), while ascorbic acid, reduced glutathione and superoxide dismutase activity were decreased in patients with T2D compared to healthy controls (p<0.001). The meal rich...
|
|
| |
|
| |
|
|
Mechanisms of insulin resistance and β - cell failure in type 2 diabetes. Effective diet against o minous octet
Kahleová, Hana ; Pelikánová, Terezie (advisor) ; Haluzík, Martin (referee) ; Vondra, Karel (referee)
Background and Aims: Dietary intervention is one of the key components in type 2 diabetes (T2D) management. Vegetarian diet is a promising alternative in the nutritional treatment of T2D. The aims of our study were: 1. To compare the effects of vegetarian and conventional diabetic diet with the same caloric restriction on insulin resistance, volume of visceral fat and plasma concentrations of oxidative stress markers after a 12-weeks-diet-intervention and subsequent 12-weeks of diet plus aerobic exercise training in subjects with T2D. 2. To explore the effect of 12 weeks of diet intervention and subsequent 12 weeks of diet combined with aerobic exercise training on -cell function and to evaluate the role of gastrointestinal peptides in subjects with T2D. 3. To study quality of life, Beck depression score and changes in eating behaviour in response to a vegetarian and a conventional diabetic diet. 4. To explore the role of changes in fatty acid composition of serum phospholipids in diet-induced changes in insulin sensitivity in subjects with T2D. 5. To follow-up our patients 1 year from the end of the intervention.
|
|
|
The effect of transplantation therapy on diabetic complications
Bouček, Petr ; Pelikánová, Terezie (advisor) ; Vondra, Karel (referee) ; Rychlík, Ivan (referee)
Microangiopathic (retinopathy, nephropathy, and neuropathy) and macroangiopathic complications are the major causes of morbidity and mortality of diabetic patients. The main aims of the thesis were the assessment of the effect of pancreas transplantation with long-term normoglycemia on the course of small fibre diabetic neuropathy in type 1 diabetic patients and the comparison of the effect of kidney transplantation on the prognosis of type 2 diabetic and non-diabetic patients. Selected parameters of autonomic nerve function (cardiovascular reflex tests and spectral analysis of heart rate variability) and intraepidermal nerve fibre density in skin biopsies were assessed prospectively following simultaneous kidney and pancreas transplantation in type 1 diabetic patients. In type 2 diabetic patients, patient and graft survival and the occurrence of complications following kidney transplantation were retrospectively compared to matched non-diabetic controls. Advanced stages of diabetic neuropathy were present in type 1 diabetic patients at the time of transplantation and no significant improvement was seen in any of the assessed parameters following pancreas transplantation with long-term normoglycemia, which is indicative of the presence of irreversible structural small nerve fibre changes. Following kidney...
|
|
|
Purinergic Modulation of NMDA-evoked Release of Noradrenaline from Slices of Rat Brain Cortex
Pelikánová, Tereza ; Vopršalová, Marie (advisor) ; Žáčková, Pavla (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Farmacology and Toxicology Performed at: the Faculty of Pharmacy, University of Porto Candidate: Tereza Pelikánová Supervisors: Maria da Glória Correia da Silva Queiroz, PhD PharmDr. Marie Vopršalová, CSc. Title of diploma thesis: Purinergic Modulation of NMDA-evoked Release of Noradrenaline from Slices of Rat Brain Cortex ABSTRACT In the rat brain cortex, noradrenaline (NA) release can be triggered by activation of neurons projecting from locus coeruleus and by locally released glutamate. ATP released from astrocytes may also activate P2 receptors contributing to the modulation of neuron-glia signalling in noradrenergic and glutamatergic transmissions. The P2Y1 receptor subtype has been shown to modulate cortical NMDA receptor channels, but the subtypes of purinergic receptors involved in modulation of NA release in brain cortex remain unknown. The aim of this study was to identify the purinergic receptors involved in the modulation of NA release evoked by activation of NMDA receptors in rat cerebral cortex. Brain slices were incubated with [3H]-NA, superfused with buffer with 0 Mg2+ and stimulated for two periods (S1 and S2) with 30 μM NMDA (N-methyl-D-aspartate) applied for 2 min, with an interval of 45 min. During...
|
|
|
Insulin Resistance and Metabolic inFlexibility : the Influence of Renin Angiotensin System Inhibition
Wohl, Petr ; Pelikánová, Terezie (advisor) ; Prázný, Martin (referee) ; Vondra, Karel (referee)
Insulin resistance (IR) is considered to be an important factor influencing the progression of atherosclerosis and is associated with higher morbidity and mortality. IR is a common feature of diabetes mellitus Type 2 and obesity. Many authors consider IR being the crucial abnormality of the metabolic syndrome which is characterized by the essential hypertension, hyperliproteinemia, visceral obesity, endothel dysfunction and many other abnormalities. Impaired insulin action (IR) is also described in diabetes mellitus Type 1, however this phenomenon has not been fully explained. The subjects of dissertation thesis was directed on the IR importance in diabetic Type 1 patients as well as on the renin angiotensin system inhibition in patients with IR and metabolic syndrome with impaired glucose homeostasis. Hyperinsulinemic euglycemic clamp is used in combination with indirect calorimetry to estimate the IR in vivo in humans. In our project we focused on a) the existence of the metabolic inflexibility phenomenon in type 1 diabetic patients b) the methodological evaluation of the hyperinsulinemic euglycemic clamp procedure in the same group c) the influence of renin angiotensin system inhibition with angiotensin II type 1 receptor inhibitor telmisartan in patients with metabolic syndrome and impaired glucose...
|
|
|
Mechanisms of insulin resistance in humans with focus on adipose tissue
Švehlíková, Eva ; Pelikánová, Terezie (advisor) ; Vondra, Karel (referee) ; Prázný, Martin (referee)
Endocrine activity of adipose tissue is implicated in the development of insulin resistance (IR). The thesis aimed to extend the knowledge of mechanisms contributing to IR. Study I - To investigate the effect of acute hyperinsulinaemia and acute angiotensin II type 1 receptor blockade (ARB) on plasma concentrations and subcutaneous adipose tissue (SAT) expressions of selected adipokines in patients with type 2 diabetes and healthy controls Study II - To investigate the effect of 3-week telmisartan treatment on insulin resistance and plasma concentrations and SAT expressions of selected adipokines in subjects with metabolic syndrome and impaired fasting glucose (IFG) Study III - To investigate the effect of prolonged hypertriglyceridaemia on plasma concentrations and SAT expressions of selected adipokines in patients with type 2 diabetes and healthy control subjects Study IV - To assess the plasma concentrations and SAT expressions of selected adipokines in subjects with different categories of glucose intolerance Methodology: Hyperinsulinaemic-euglycaemic clamp, Intralipid infusion and saline infusion were used to simulate specific metabolic conditions in vivo in 4 groups: 8 young healthy men, 11 overweight/obese patients with type 2 diabetes, 12 age-matched healthy controls and 12 overweight/obese patients...
|
|
| |
guest ::
RSS feed.