Michal Andel

Charles University, Third Faculty of Medicine · 2nd Department of Internal Medicine and Research Centre for Nutrition Metabolism and Diabetes

Background Hyperglycaemia was shown to be among the features of severe acute COVID-19 infection both in the acute and convalescence period. Mechanisms contributing to its development and/or maintenance in a post-COVID phase are still unclear. Materials and Methods Survivors of severe COVID-19 but without a known history of diabetes were examined a...

Aims/hypothesis: Beta-cell failure plays a fundamental role in type 2 diabetes mellitus (T2DM) development. It has been shown that the beta-cells are among the most sensitive to hypoxia. We aimed to analyze whether decrease in pancreatic perfusion relates to 1/decline in beta-cell function and 2/visceral fat accumulation in patients with T2DM. Me...

As not much is known about the prevalence and predictors of nutritional deficiencies among vegans in the Czech Republic, we evaluated whether supplement use and duration of adherence to the vegan diet are associated with the risk of cobalamin and iron deficiencies. Associations between self-reported supplementation and duration of vegan diet with b...

Non-alcoholic fatty liver disease and its complications are frequent causes of liver-related morbidity and mortality. Incretin glucagon-like peptide-1 (GLP-1) affects liver functions and metabolism. Although GLP-1 analogues are widely used in clinical practice, information regarding their potential toxic effect on hepatocytes in vitro is missing. T...

Background: Testing for autoantibodies against the zinc transporter ZnT8 (ZnTA) is becoming routine in pediatric diabetes. However, available data are inconclusive when focusing on adult-onset diabetes, including autoimmune diabetes, which does not require insulin at diagnosis (LADA). Basic procedures: We examined the ZnTA prevalence and titers a...

Objective: The aim of the study is to assess the risk of malnutrition among institutionalized elderly individuals in North Bohemia and compare it to the risk of malnutrition in the capital city of Prague, Czech Republic. In the Czech Republic, very few studies have been conducted with the goal of describing and evaluating the nutritional status of...

Introduction: The aim of this study was to determine the level of awareness of hypoglycemia, the level of fear for hypoglycemia, and the response to hypoglycemic events among insulin-treated diabetes patients from Central and Eastern Europe (CEE). The impact of hypoglycemia on the use of healthcare resources and patient productivity was also asses...

cancer ranks among the major death causes worldwide. extensive research in the field led to a development of potent anticancer drugs that improved prognosis of patients with cancer. there is a considerable amount of evidence on metabolic pathways in tumour cells. in spite of that, much less is known about metabolic phenotype of the host organism. c...

Objectives: Propofol may adversely affect the function of mitochondria and the clinical features of propofol infusion syndrome suggest that this may be linked to propofol-related bioenergetic failure. We aimed to assess the effect of therapeutic propofol concentrations on energy metabolism in human skeletal muscle cells. Design: In vitro study o...

A personalized antidiabetic therapy is not yet part of the official guidelines of professional societies for clinical practice. The aim of this study was to evaluate the serum C-peptide and plasma glucose levels in patients with type 2 diabetes mellitus (T2DM) after oral administration of whey proteins. Sixteen overweight T2DM Caucasians with good...

Transcription factors (TF) are key proteins that are essential for initiation and regulation of gene expression. Hepatocyte nuclear factors (HNF) represent specific TF that regulate transcription of a wide variety of genes necessary for embryonic development and metabolic homeostasis. The dysfunction of these TF is associated with diabetes mellitus...

Glucagon-like peptide-1 (GLP-1) is an incretin known for proliferative and antiapoptotic effects on various tissues. Exenatide and Liraglutide are GLP-1 analogues used in clinical practice as antidiabetic drugs. Since GLP-1 and its analogues exert significant effect on liver metabolism and since changes in intermediary metabolism play an important...

Background/aims: Branched chain amino acids (BCAAs) are known to exert an insulinotropic effect. Whether this effect is mediated by incretins (glucagon like peptide 1 [GLP-1] or glucose-dependent insulinotropic peptide [GIP]) is not known. The aim of this study was to show whether an equivalent dose of BCAA elicits a greater insulin and incretin r...

Background/objectives: Branched chain amino acids (BCAA) are among nutrients strongly linked with insulin sensitivity (IS) measures. We investigated the effects of a chronic increase of BCAA intake on IS in two groups of healthy subjects differing in their basal consumption of BCAA, that is, vegans and omnivores. Subjects/methods: Eight vegans a...

Non-alcoholic fatty liver disease (NAFLD) is considered to be a hepatic manifestation of metabolic syndrome and is associated with insulin resistance, type 2 diabetes mellitus, obesity, hypertension, and dyslipidemia (T. Fukuhara et al. Hepatogastroenterology 2014; 61: 323–328). The current gold standard for the diagnosis of hepatic steatosis is a...

Aim: To assess intraindividually the effects of DPP-IV inhibition on the subpopulations of immune cells in type 2 diabetes mellitus (DM2) patients during the course of treatment with sitagliptin. Methods: In this open label non-randomized observational study with a control group DM2 patients were examined before the initiation of the DPP-IV inhi...

Unlabelled: We present the results of an independent, drug company-unsupported follow-up of patients with type 2 diabetes mellitus (T2DM) treated with the dipeptidyl peptidase 4 inhibitor sitagliptin. 29 patients (16 men, 13 women) used sitagliptin 100 mg daily for one year as an add-on to their chronic antidiabetic therapy. 16 type diabetic patie...

Background/objectives: Our aim was to compare expressions of 6 microRNAs (miRNAs) in patients with pancreatic ductal adenocarcinoma (PAC) and non-cancer patients, moreover according to the presence or absence of diabetes mellitus. Methods: Expressions of miRNA-192, -196, -200, -21, -30 and -423 were measured in 77 patients with PAC and 64 non-ca...

Introduction Propofol infusion syndrome (PRIS) is a rare, but potentially lethal adverse effect of a commonly used drug. We aimed to review and correlate experimental and clinical data about this syndrome. Methods We searched for all case reports published between 1990 and 2014 and for all experimental studies on PRIS pathophysiology. We analysed...

Obesity is often associated with metabolic impairments in peripheral tissues. Evidence suggests an excess of free fatty acids (FFA) as one factor linking obesity and related pathological conditions and the impact of FFA overload on skeletal muscle metabolism is described herein. Obesity is associated with dysfunctional adipose tissue unable to buff...

Objectives Sulfonylurea derivatives are widely used for clinical treatment of human subjects with Maturity Onset Diabetes of the Young (MODY) caused by mutations in HNF-1α or HNF-4α despite the mechanism leading to their hypersensitivity is incompletely understood. In Hnf1a-/- mice, serum concentrations and half-life of sulfonylurea derivatives are...

The mRNA expression of PPARδ. a, b) Myotubes were treated with 1 μM PPARδ agonist GW501516 (a) or 1 μM PPARδ antagonist GSK0660 (b) for 24 h. c, d, e) Myotubes were treated with 100 μM (c), 300 μM (d) and 600 μM (e) total concentration of palmitic acid (PAM), unsaturated FFA (OLA, LNA, ALA) or with combinations: PAM + unsaturated FFA in a ratio 1:1...

Mitochondrial respiration (oxygen consumption rates, OCR) in myotubes measured under different respiratory conditions. a, b) Myotubes were treated with 100 μM (c), 300 μM (d) and 600 μM (e) total concentration of palmitic acid (PAM), unsaturated FFA (OLA, LNA, ALA) or with combinations: PAM + unsaturated FFA in a ratio 1:1 or PAM + 1 μM GW501516 fo...

Pancreatic cancer is a disease with increasing incidence and high (and nearly unchanged) lethality that is caused mainly due to its late diagnosis. Risk factors for neoplastic transformation are especially chronic pancreatitis, diabetes mellitus, but also obesity and smoking. The search for suitable early markers becomes a key element of research i...

Unsaturated free fatty acids (FFA) are able to prevent deleterious effects of saturated FFA in skeletal muscle cells although the mechanisms involved are still not completely understood. FFA act as endogenous ligands of peroxisome proliferator-activated receptors (PPAR), transcription factors regulating the expression of genes involved in lipid met...

Sodium phosphate purgatives are used for bowel preparation before endoscopic or radiologic examination and occasionally for treatment of severe obstipation. Generally, they are well tolerated and effective; however, safety concerns exist regarding serious renal injury and electrolyte disturbances after administration of these drugs. The review pres...

Background: The lipophilic positively charged moiety of triphenylphosphonium (TPP+) has been used to target a range of biologically active compounds including antioxidants, spin-traps and other probes into mitochondria. The moiety itself, while often considered biologically inert, appears to influence mitochondrial metabolism. Methodology/princip...

Newly-onset diabetes mellitus (DM) in middle-aged and older people may be an early symptom of pancreatic cancer (PC). However, sensitive markers for PC are still missing. MicroRNAs (miRNAs) play an important role in a cell response regulation. Significant changes in miRNA expressions were observed in cancers. Our goal was to compare expressions of...

Background The protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene encodes the lymphoid tyrosine phosphatase (LYP), which is expressed primarily in lymphoid tissues. The functional but geographically highly variable PTPN22 single nucleotide polymorphisms (SNPs), particularly c.1858C>T, contribute to the onset and progression of autoimmu...

Diabetes mellitus and obesity are among the major risk factors for cardiovascular diseases, which are the most common cause of mortality among adults in the Czech Republic. Cancer diseases placed second. An increased frequency of cancers was observed in patients with diabetes mellitus and obese subjects. Both units represent an independent risk fac...

Impaired skeletal muscle glucose disposal is a pathophysiological hallmark of type 2 diabetes. Easy and reproducible method of muscle sampling was needed for study of subcellular basis of its developement, i.e. percutaneous muscle biopsy. This technique is nowaday a routine method of clinical diabetes research and has been described in details sinc...

Althoug pancreatic steatosis has been known for a decades, it attracts more attention in recent years, especially in the context of the increasing incidence of obesity and metabolic syndrome, with which it is undoubtedly closely related. The link can be also found with the incidence of type 2 diabetes mellitus, pancreatic exocrine dysfunction, acut...

Impairment of mucosal barrier integrity of small intestine might be causative in immune-mediated gastrointestinal diseases. We tested the markers of epithelial apoptosis - cytokeratin 18 caspase-cleaved fragment (cCK-18), and enterocyte damage - intestinal fatty acid-binding protein (I-FABP) and soluble CD14 (sCD14) in sera of patients with untreat...

Insulin secretion in patients with manifested diabetes mellitus tends to disappear months to decades after the diagnosis, which is a clear sign of a gradual loss of pancreatic islet beta-cells. In our sample of 30 type 2 diabetic patients, whose disease manifested between 30 and 45 years of age, about a half have retained or even increased insulin...

Insulin secretion in patients with manifested diabetes mellitus tends to disappear months to decades after the diagnosis, which is a clear sign of a gradual loss of pancreatic islet beta-cells. In our sample of 30 type 2 diabetic patients, whose disease manifested between 30 and 45 years of age, about a half have retained or even increased insulin...

U pacientů, u kterých se manifestoval diabetes mellitus, dochází po měsících až desetiletích trvání choroby k vyhasnutí sekrece inzulinu, což je téměř jistým znamením úbytku B-buněk Langerhansových ostrůvků. U souboru 30 pacientů, u kterých se choroba manifestovala mezi 30–45 roky a byli diagnostikováni jako diabetici 2. typu, má po 30 letech trván...

Both celiac disease and osteoporosis are common diseases which are considered an emerging problem in medicine. Celiac disease is a condition at high risk for secondary osteoporosis. Osteoporosis or osteopenia are typically present in untreated adult symptomatic celiac disease with an overt malabsorption syndrome, but is found in about 50 % in subop...

Aim: The aim of this study was to evaluate the effect of long-term administration of liquid nutritional supplement with increased amounts of whey protein and reduced amounts of lactose, produced in accordance with a new recipe "Nutrisen" on the elderly living in institutionalized care. Methods: The study was carried out from May to July, 2013, o...

Background/Aims: Deleterious effects of saturated fatty acids in skeletal muscle cells are well known but their impact on mitochondrial respiration has not been well studied. Mitochondrial oxidative damage has been implicated to play a role in their effect. The purpose of this study was to evaluate viability, mtDNA integrity and mitochondrial respi...

Islet cell autoantibodies are associated with autoimmune insulitis and belong to the diagnostic criteria of Type 1 diabetes mellitus. However, growing evidence suggests that autoantibodies are present in other types of diabetes. Here, we focus on the autoantibody incidence in Czech patients with maturity-onset diabetes of the young and analyse thei...

Isolated granulomatous noncaseating pancreatitis is a rare condition exceptionally described in human population. We demonstrate a case of the a 71-years-old female patient suffering from recent diabetes mellitus, generalized atherosclerosis and hypertension who died due to pulmonary embolism and terminal bronchopneumonia. Lipomatosis of pancreatic...

The review article summarizes the principles of hedonic regulation of food intake which represents the food intake independent on the maintenance of homeostasis. The theory describing hedonic regulation, so called Incentive Salience Theory, comprises three major processes: liking (positive attribution to food stimulus), wanting (motivation to gain...

Looking from the point of risk of development of cancer are most antidiabetic drugs either neutral or lead to mild increase of the risk. Metformin is the only antidiabetic drug, which in retrospective studies decreased the risk of malignant diseases (OR 0,54-0,70). In the patients treated with metformin were observed also better results of antitumo...

Dipeptidyl peptidase-4 inhibitors represent a newer class of antidiabetic drugs, which we use more in type 2 diabetes mellitus treatment. Recenty, there are several new information regarding their effects on immunity. Partial immunosuppression was observed after their administration, maybe due to affecting chemotaxis and T lymphocyte migration. Thi...

Case of severe persistent hypoglycaemia in non-diabetic patient caused by atypic antipsychotic olanzapine administration is presented in the case report. Hypoglycaemia was associated with endogenous hypersecretion of insulin and cummulative dose of more than 1000mg of intavenous glukose was needed to maintain normoglycaemia. Similar case-reports fr...

Sodium phosphate solutions are commonly used to cleanse the bowel in preparation for colonoscopy, for barium enema or surgical procedures and eventually for treatment of severe constipation. Though relatively safe, these drugs must be used with caution in patients with kidney disease, small intestinal disorders, or poor gut motility and are prohibi...

Background/objectives: Vegans have a lower incidence of insulin resistance (IR)-associated diseases and a higher insulin sensitivity (IS) compared with omnivores. The aim of this study was to examine whether the higher IS in vegans relates to markers of mitochondrial biogenesis and to intramyocellular lipid (IMCL) content. Subjects/methods: Elev...

The review article summarizes a very complex process of appetite regulation: the part focused on homeostatic regulation of food intake. The aim of homeostatic regulation is to achieve energy balance, stabile weight and optimal nutrient intake, in contrast to hedonic regulation of food intake, in which emotional and motivational factors are involved...

Substituting galactose for glucose in cell culture media has been suggested to enhance mitochondrial metabolism in a variety of cell lines. We studied the effects of carbohydrate availability on growth, differentiation and metabolism of C2C12 myoblasts and myotubes. We measured growth rates, ability to differentiate, citrate synthase and respirator...

Type 2 diabetes moderately increases predisposition for manifestation of tumor disease. Both drugs stimulating insulin secretion (insulin secretagogues) and insulin injection therapy also moderately increases risk of tumor manifestation (OR approx 1.3). According to some reports pyoglitazon therapy could be of increased risk of bladder cancer. On t...

Effects of glucagonlike peptide 1 (GLP1) on liver cells are very intensively studied. In the metabolism of saccharides GLP1 stimulates synthesis of glycogen and reduces glucose production - thus acting like insulin. In the lipid metabolism it enhances fatty acid oxidation and lipid transport from hepatocytes while reducing de novo lipogenesis - eff...

It was recently suggested that routine islet cell autoantibody testing should be performed to discriminate maturity-onset diabetes of the young (MODY) from type 1 diabetes mellitus (T1DM). This is the first report ever to describe the familial manifestation of T1DM autoimmunity in nonobese HNF1A-MODY subjects and the presence of islet antigen-2 (IA...

Background: There are few studies in the Czech Republic describing and evaluating the nutritional status of institutionalized elderly. Methods: Data were collected from 659 women and 156 men aged 65 years and older and living in retirement homes in and around Prague. Data included: a Mini-Nutritional Assessment (MNA questionnaire), anthropometri...

Aim. GCK-MODY is an autosomal dominant form of diabetes caused by heterozygous mutations in the glucokinase gene leading to a lifelong mild hyperglycemia. The risk of macrovascular complications is considered low, but studies are limited. We, therefore, investigated the carotid intima-media thickness (CIMT) as an indicator of macrovascular complica...

Gliptins (e.g. sitagliptin, vildagliptin) are novel anti-diabetic drugs that improve insulin secretion by a GLP-1 mediated mechanism by inhibiting the protease dipeptidyl peptidase-IV (DPP-IV) with a consequent increase in the bioavailability of incretins. DPP-IV is a multifunctional membrane bound serine protease identical with the marker of activ...

Endothelial cells form the inner layer of the vascular system. They ensure the transport between blood and insterstitium and take part in the regulation of vascular tonus, in the equlibrium of thrombosis/thrombolysis, and in immune processes. Therefore an endothelial cell has very high energetic demands. The most important source of energy for the...

Major milk proteins. casein and whey proteins. are high-quality proteins with unique insulinotropic property that do not increase postprandial blood glucose upon administration. It is believed that these proteins increase insulin secretion by both a direct effect of particulary branched chain amino acids on β-cell of islets of Langerhans in pancrea...

Type 2 diabetes moderately increases predisposition for manifestation of tumor disease. Both drugs stimulating insulin secretion (insulin secretagogues) and insulin injection therapy also moderately increases risk of tumor manifestation (OR approx. 1,3). According to some reports pyoglitazon therapy could be of increased risk of bladder cancer. On...

This review analyses recent understanding of the role of the intestinal barrier function in the development of type 1 and type 2 diabetes. Intestinal barrier is complex homeostatic system consisting of intestinal permeability, intestinal immunity as well as intestinal microbiota. Via alterations in the intestinal permeability, intestinal barrier fu...

Our study compared total C-peptide secretion after administration of whey proteins and whey proteins in combination with glucose with results of classical tests assessing beta cell function in the pancreas of healthy individuals. Eight young, healthy (7 males, 1 female; aged 20-26 years), non-obese (BMI: 17-25.9 kg/m(2)) participants with normal gl...

Background/aims: Oxidized low-density lipoprotein (oxLDL) in complex with β2-glycoprotein I (β2GPI) has been associated with autoimmune diseases, diabetes mellitus, chronic renal disease and coronary atherosclerosis. The aim of our study was to determine whether plasma levels of oxLDL/β2GPI complexes are associated with insulin resistance, inflamm...

Czech cardiovascular disease (CVD) morbidity and mortality rates are among the highest in the world. A 2-year community-based project was designed to increase CVD awareness and knowledge and behavior change skills, thus stimulating change in CVD-related behaviors. Dubec, a Czech town located just outside Prague, was the study community. Risk-factor...

Subcutaneous apomorphine, a dopaminergic agonist, is used as a neuroendocrine probe for assessing central dopaminergic activity. The aim of our study was to test sublingual apomorphine for the same purpose. We administered sublingual apomorphine in a weight-dependent dose (0.033mg/kg) to 42 healthy men. Prolactin and growth hormone levels were meas...

Background/aims: Central dopaminergic activity is probably linked to regulation of glucose and lipid metabolism and weight maintenance. The aim of our study was to evaluate the relationship between central dopaminergic activity measured using the apomorphine challenge test and metabolic parameters in healthy men. Methods: Forty-two healthy men (...

Free fatty acids (FFA) play an important physiological role in the body, however, chronically elevated plasma FFA are associated with various pathophysiological consequences. Elevated FFA concentrations are linked with the onset of peripheral insulin resistance. Skeletal muscle is an important target tissue for the action of FFA. It was shown that...