The aim of this study was to investigate the effects of troglitazone (TRO) - a new insulin-sensitizing agent - on some metabolic parameters in an experimental model of hypertriglyceridemia and insulin resistance, hereditary hypertriglyceridemic rats, and to compare its effects with those of vitamin E, an antioxidant agent. Three groups of the above rats were fed diets with a high content of sucrose (70 % of energy as sucrose) for four weeks. The first group was supplemented with TRO (120 mg/kg diet), the second one with vitamin E (500 mg/kg diet), and the third group served as the control. Vitamin E supplementation did not lower serum triglycerides (2.42±0.41 vs. 3.39±0.37 mmol/l, N.S.) while TRO did (1.87±0.24 vs. 3.39±0.37 mmol/l, p<0.01). Neither TRO nor vitamin E influenced the serum levels of free fatty acids (FFA). Both drugs influenced the spectrum of fatty acids in serum phospholipids - TRO increased the levels of polyunsaturated fatty acids (PUFA) n-6 (36.04±1.61 vs. 19.65±1.56 mol %, p<0.001), vitamin E increased the levels of PUFA n-3 (13.30±0.87 vs. 6.79±0.87 mol %, p<0.001) and decreased the levels of saturated fatty acids (32.97±0.58 vs. 51.45±4.01 mol %, p<0.01). In conclusion, TRO lowered the level of serum triglycerides but vitamin E did not have this effect in hypertriglyceridemic rats. Compared with TRO, vitamin E had a different effect on the spectrum of fatty acids in serum phospholipids., Š. Chvojková, L. Kazdová, J. Divišová., and Obsahuje bibliografii
Obezita je v kombinaci s dalšími složkami syndromu inzulinové rezistence výrazným rizikovým faktorem aterosklerózy a jejich komplikací. Přesné mechanizmy propojení uvedených onemocnění jsou dosud objasněny pouze zčásti. Jedním z možných pojítek je porucha endokrinní funkce tukové tkáně, která při obezitě produkuje zvýšené množství prozánětlivých a proaterogenních hormonů a cytokinů a méně faktorů protektivních. Prakticky jediným z hormonů tukové tkáně s prokázaným protizánětlivým a antiaterosklerotickým účinkem je hormon adiponektin. Tento hormon je produkován převážně adipocyty a jeho hladiny jsou sníženy právě u pacientů s obezitou, inzulinovou rezistencí a aterosklerózou. Cílem tohoto článku je shrnout současné experimentální a klinické poznatky o vztahu adiponektinu k ateroskleróze a diskutovat možné využití tohoto hormonu v predikci aterosklerózy a případné perspektivy jeho využití v prevenci a léčbě tohoto onemocnění., Denisa Haluzíková, T. Roubíček, Martin Haluzík, and Lit. 39
Kyselina močová je u človeka biologicky aktívny koncový produkt metabolizmu purínov. Zvýšené koncentrácie kyseliny močovej sprevádzajú metabolický syndróm a jeho komponenty už u detí a mladistvých. K hyperurikémii prispieva konzumácia nápojov prisládzaných fruktózou, nakoľko je jediným sacharidom, pri ktorého metabolizme vzniká kyselina močová. Súčasné vedomosti neumožňujú odlíšiť, či je hyperurikémia kauzálnou príčinou komponentov metabolického syndrómu, alebo len sprievodným znakom naznačujúcim zvýšené riziko vzniku kardiovaskulárnych ochorení. V súčasnosti neexistuje konsenzus či a ako liečiť asymptomatickú hyperurikémiu u detí a mladistvých. Zaujať zásadný postoj k týmto otázkam umožnia len výsledky randomizovaných kontrolovaných prospektívnych štúdií, ktoré poskytnú dôkazy o prospešných účinkoch tejto liečby na prevalenciu metabolického syndrómu a incidenciu kardiovaskulárnych chorôb., In humans, uric acid represents a biologically active end-product of purine nucleotides. Several studies in children and adolescents documented an association between hyperuricaemia and the components metabolic syndrome. High intake of fructose-sweetened beverages might increase uricaemia, since fructose is the only saccharide which metabolism results in the formation of uric acid. Current knowledge does not allow distinguishing whether hyperuricaemia is causally related to the components of metabolic syndrome, or rather represents a marker of an enhanced risk, and poor outcome. No guidelines exist whether or not to treat asymptomatic hyperuricaemia in the adolescents. Randomized controlled prospective clinical studies are needed to elucidate whether uric acid-lowering management would beneficially affect the prevalence of metabolic syndrome, and the incidence of cardiovascular disease., and Ivana Koborová, Radana Gurecká, Anna Hlavatá, Katarína Šebeková
Visfatin was originally described as an adipokine with insulin mimetic effects. Recently, it was found that visfatin is identical with the Nampt (nicotinamide phosphoribosyltransferase) gene that codes for an intra- and extracellular NAD biosynthetic enzyme and is predominantly expressed outside the adipose tissue. In the current study, we found strong protein and mRNA expression of visfatin in rat heart, liver, kidney, and muscle, while the expression of visfatin in visceral fat was significantly lower and undetectable in subcutaneous fat. The insulin-mimetic effects of visfatin (extracellular form of Nampt or eNampt) are controversial and even less is known about autocrine effects of visfatin (intracellular form of Nampt or iNampt). Since liver plays a major role in glucose metabolism, we studied visfatin effects on insulin-stimulated cellular glucose uptake in Fao rat hepatocytes using RNA interference (RNAi). RNAi-mediated downregulation of visfatin expression in Fao cells was associated with significantly reduced NAD biosynthesis (0.3±0.01 vs. 0.5±0.01 mmol/h/g, P<0.05) and with significantly decreased incremental glucose uptake after stimulation with insulin when compared to controls with normal expression of visfatin (0.6±0.2 vs. 2.2±0.5 nnmol/g/2 h, P=0.02). These results provide evidence that visfatin exhibits important autocrine effects on sensitivity of liver cells to insulin action possibly through its effects on NAD biosynthesis., V. Škop ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Adipocyte fatty acid binding protein (A-FABP) is a novel adipokine involved in the regulation of lipid and glucose metabolism and inflammation. To evaluate its potential role in the development of postoperative hyperglycemia and insulin resistance we assessed A-FABP serum concentrations and mRNA expression in skeletal and myocardial muscle, subcutan eous and epicardial adipose tissue and peripheral monocytes in 11 diabetic and 20 age- and sex-matched non-diabetic patients undergoing elective cardiac surgery. Baseline serum A-FABP did not differ between the groups (31.1±5.1 vs. 25.9±4.6 ng /ml, p=0.175). Cardiac surgery markedly increased serum A-FABP in both groups with a rapid peak at the end of surgery foll owed by a gradual decrease to baseline values during the next 48 h with no significant difference between the groups at any timepoint. These trends were analogous to postoperative excursions of plasma glucose, insulin and selected proinflammatory markers. Cardiac surgery increased A-FABP mRNA expression in peripheral monocytes, while no effect was observed in adipose tissue or muscle. Our data suggest that circulating A-FABP might be involved in the development of acute perioperative stress response, insulin resistance and hyperglycemia of critically ill irrespectively of the presence of diab etes mellitus., T. Kotulak ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Patients with obesity and type 2 diabetes often display high levels of the anti-diabetic factor fibroblast growth factor-21 (FGF21), suggesting that the overproduction of FGF21 may result from increased adiposity in an attempt by white adipose tissue (WAT) to counteract insulin resistance. However, the production of FGF21 diabetes in the absence of WAT has not been examined. In this study, we investigated the effects of lipodystrophy in A-ZIP F-1 mice on FGF21 production in relation to diabetes. A-ZIP F-1 mice displayed high FGF21 plasma levels resulting from enhanced FGF21 mRNA expression in the liver. Concomitant enhancement of FGF21 receptor (FGFR1) and glucose transporter 1 (GLUT-1) mRNA expression was observed in the muscles of A-ZIP F-1 mice. Furthermore, the activation of hypothalamic NPY and AgRP mRNA expression positively correlated with plasma levels of FGF21 but not active ghrelin. Our study demonstrates that an increased FGF21 plasma level in lipodystrophic A-ZIP F-1 mice results mainly from up-regulated liver production but does not suffice to overcome the lipodystrophy-induced severe type 2-diabetes and insulin resistance in the liver linked to the augmented liver fat deposition., A. Špolcová, M. Holubová, B. Mikulášková, V. Nagelová, A. Štofková, Z. Lacinová, J. Jurčovičová, M. Haluzík, L. Maletínská, B. Železná., and Obsahuje bibliografii
We assessed the effect of the previously uncovered gap junctio n protein alpha 8 (Gja8) mutation present in spontaneously hypertensive rat - dominant cataract (SHR - Dca ) strain on blood pressure, metabolic profile, and heart and renal transcriptomes. Adult, standard chow-fed male rats of SHR and SHR - Dca strains were used. We found a significant, consistent 10-15 mmHg decrease in both systolic and diastolic blood pressures in SHR - Dca compared with SHR (P<0.01 and P<0.05 , respectively; repeated measures analysis of variance (ANOVA)). With immunohistochemistry, we were able to localize Gja8 in heart, kidney, aorta, liver, and lungs, mostly in endothelium; with no differences in expression between strains. SHR - Dca rats showed decreased body weight, high-density lipoprotein cholesterol concentrations and basa l insulin sensitivity in muscle. There were 21 transc ripts common to the sets of 303 transcripts in kidney and 487 in heart showing >1.2-fold difference in expression between SHR and SHR - Dca. Tumor necrosis factor was the most significant upstream regulato r and glial cell-derived neurotrophic factor family ligand-receptor interactions was the common enriched and downregulated canonical pathway both in heart and kidney of SHR - Dca. The connexin 50 mutation L7Q lowers blood pressure in the SHR - Dca strain, decr eases high-density lipoprotein cholesterol, and leads to substantial transcriptome changes in heart and kidney., O. Šeda, F. Liška, M. Pravenec, Z. Vernerová, L. Kazdová, D. Křenová, V. Zídek, L. Šedová, M. Krupková, V. Křen., and Obsahuje bibliografii
Insulin resistance associated with dyslipidemia enhances cardiovascular risk. Several atherogenic indexes have been suggested to give more precise information about the risk. The aim of our study was to estimate, which atherogenic index correlates better with parameters of insulin resistance. Furthermore, we compared the parameters of lipid metabolism and insulin resistance between smokers and non-smokers. In our cross-sectional study we enrolled 729 patients with dyslipidemia which were divided into two groups - non-smokers (586) and smokers (143). We measured lipid profile, parameters of insulin resistance (fasting glycemia, insulin, HOMA-IR, C-peptide, proinsulin) and calculated atherogenic indexes - atherogenic index of plasma (log (TAG/HDL-C), AIP), ApoB/ApoA1 index and nonHDL-C. AIP was found out to show stronger correlations with parameters of insulin resistance (p<0.001, correlation coefficients ranging between 0.457 and 0.243) than other indexes (ApoB/ApoA1 or nonHDL cholesterol). AIP correlated with parameters of insulin resistance both in smokers and nonsmokers, but after adjustment (for age, body mass index, waist circumference) persisting only in non-smokers. Smokers had a wider waist circumference and a proatherogenic lipid profile. Smoking increases the risk of developing metabolic syndrome. AIP can be used in daily praxis for predicting insulin resistance in patients with dyslipidemia, predominantly in non-smokers., L'. Cibičková, D. Karásek, K. Langová, H. Vaverková, J. Orság, J. Lukeš, D. Novotný., and Obsahuje bibliografii
This study aimed to examine relationships between DHEA(S), anthropometric parameters, oral glucose tolerance test derived data and lipid spectra in a Czech non-diabetic population. 380 healthy volunteers both with and without a family history of diabetes type 2 (DM2) were en rolled into the study (women: n=235, age 28.9±9.4 years, BMI 22.3±4.5 kg/m2, men: n=145, age 32.3±10.0 years, BMI 24.7±3.6 kg/m2). Spearman’s correlations (both without and with the adjustment for age, age and BMI), as well as ANCOVA were used. Non-adjusted data showed many “beneficial” correlations between DHEA(S) and both anthropometric and metabolic variables. Statistical analysis revealed that almost all correlations of DHEA(S) to adiposity and fat distribution in men as well as in women disappeared after the adjustment. There are, however, differences between men and women in the correlation of DHEA(S) to insulin sensitivity and lipid levels. The use of hormonal contraceptives (COC) is also an important factor in this relationship. In men and also in women using COC, DHEA-S after adjustment correlated positively with fasting and stimulated glucose, insulin and C-peptide, and negatively with insulin sensitivity. In this respect, the benefit of DHEA(S) supplementation seems - at least in terms of its alleged antiobesity and antidiabetogenic effects - to be more than controversial., B. Bendlová, J. Vrbíková, M. Hill, M. Vaňková, P. Lukášová, J. Včelák, D. Vejražková, K. Dvořáková, R. Hampl, K. Vondra, L. Stárka., and Obsahuje bibliografii a bibliografické odkazy
Because insulin resistance is inevitably associated with cardiovascular complications, there is a need to further investigate the potential involvement of oxidative stress and the cyclo-oxygenase (COX) pathway in the vascular modifications associated to this pathological context. Endothelial function was evaluated in control and fructose-fed rats (FFR) by i) in vitro study of endothelium-dependent an d-independent relaxations of aortic rings, and ii) in vivo telemetric evaluation of pressor response to norepinephrine. After 9 weeks of diet, FFR displayed hypertriglyceridemia, hyperinsulin emia and exaggerated response to glucose overload. Aortic rings from control rats and FFR exhibited comparable endothelium-dependent relaxations to Ach. In the presence of indomethacin , relaxations were significantly reduced. FFR showed exaggerated pressor responses to norepinephrine that were abolis hed with indomethacin. Urinary nitrites/nitrates, 8-isoprostanes and thromboxane B2 excretion levels were markedly enhanced in FFR, whereas the plasma levels of 6-keto prostaglandin F1α were unchanged. In conclusion, fructose overload in rats induced hypertriglyceridemia and insulin resistance associated with an enhanced oxidative stress. This was associated with COX pathway dysregulation which could be one of the contributors to subsequent vascular dysfunction. Consequently, reduction of oxidative stress and regulation of the COX pathway could represent new potential therapeutic strategies to limit vascular dysfunction and subsequent cardiovascular complications associated with insulin resistance., A. Outdot ... [et al.]., and Obsahuje seznam literatury
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 buffer the flux of dietary lipids. Resulting increased levels and fluxes of plasma FFA lead to ectopic lipid deposition and lipotoxicity. FFA accumulated in skeletal muscle are associated with insulin resistance and overall cellular dysfunction. Mechanisms supposed to be involved in these conditions include the Randle cycle, intracellular accumulation of lipid metabolites, inflammation and mitochondrial dysfunction or mitochondrial stress. These mechanisms are described and discussed in the view of current experimental evidence with an emphasis on conflicting theories of decreased vs. increased mitochondrial fat oxidation associated with lipid overload. Since different types of FFA may induce diverse metabolic responses in skeletal muscle cells, this review also focuses on cellular mechanisms underlying the different action of saturated and unsaturated FFA., J. Tumova, M. Andel, J. Trnka., and Obsahuje bibliografii
Objective: To examine the impact of family history of diabetes mellitus 2 (DM 2) on insulin sensitivity and secretion in lean women with polycystic ovary syndrome (PCOS). Thirteen healthy women (C), 14 PCOS without family history of DM 2 (FH-) and 8 PCOS with family history of DM 2 (FH+) were examined using euglycemic hyperinsulinemic clamp and an arginine secretion test (insulin and glucagon at fasting glycemia (AIRFG and AGRFG) and at hyperglycemia (AIR14 and AG 14)). FH+ women were more insulin resistant than FH- with lower insulin sensitivity index corrected per lean body mass (p<0.05). They had significantly higher triglycerides (p<0.05) and lower HDL-cholesterol (p<0.05) than C or FH- women. Concerning insulin secretion, AIR FG was increased in FH+ women comparing FH- women (p<0.05). Disposition indices derived from AIRFG or AIR14 and insulin sensitivity index did not differ between FH+ or FH-. Thus, women with PCOS with the concomitant family history of DM 2 have lower insulin sensitivity than healthy control women. Insulin resistance observed in these women with PCOS is compensated by increased insulin secretion., J. Vrbíková, T. Grimmichová, K, Dvořáková, M. Hill, S. Stanická, K. Vondra., and Obsahuje bibliografii a bibliografické odkazy
Increased plasma total cysteine (tCys) has been associated with obesity and metabolic syndrome in human and some animal studies but the underlying mechanisms remain unclear. In this study, we aimed at evaluating the effects of high cysteine diet administered to SHR-CRP transgenic rats, a model of metabolic syndrome and inflammation. SHR-CRP rats were fed either standard (3.2 g cystine/kg diet) or high cysteine diet (HCD, enriched with additional 4 g L-cysteine/kg diet). After 4 weeks, urine, plasma and tissue samples were collected and parameters of metabolic syndrome, sulfur metabolites and hepatic gene expression were evaluated. Rats on HCD exhibited similar body weights and weights of fat depots, reduced levels of serum insulin, and reduced oxidative stress in the liver. The HCD did not change concentrations of tCys in tissues and body fluids while taurine in tissues and body fluids, and urinary sulfate were significantly increased. In contrast, betaine levels were significantly reduced possibly compensating for taurine elevation. In summary, increased Cys intake did not induce obesity while it ameliorated insulin resistance in the SHR-CRP rats, possibly due to beneficial effects of accumulating taurine., Jakub Krijt, Jitka Sokolová, Jan Šilhavý, Petr Mlejnek, Jan Kubovčiak, František Liška, Hana Malínská, Martina Hüttl, Irena Marková, Michaela Křížková, Martha H. Stipanuk, Tomáš Křížek, Tamas Ditroi, Peter Nagy, Viktor Kožich, Michal Pravenec., and Obsahuje bibliografii
Previous studies revealed altered levels of the circulating insulin-like growth factor-I (IGF-I) and of its binding protein-3 (IGFBP-3) in subjects with coronary atherosclerosis, metabolic syndrome and premature atherosclerosis. Hyperlipidemia is a powerful risk factor of atherosclerosis. We expected IGF-I and IGFBP-3 alterations in subjects with moderate/severe hyperlipidemia but without any clinical manifestation of atherosclerosis. Total IGF-I and IGFBP-3 were assessed in 56 patients with mixed hyperlipidemia (MHL; cholesterol>6.0 mmol/l, triglycerides>2.0 mmol/l), in 33 patients with isolated hypercholesterolemia (IHC; cholesterol>6.0 mmol/l, triglycerides<2.0 mmol/l), and in 29 healthy controls (cholesterol<6.0 mmol/l, triglycerides<2.0 mmol/l). The molar ratio of IGF-I/IGFBP-3 was used as a measure of free IGF-I. IHC subjects differed from controls by lower total IGF-I (164±60 vs. 209±73 ng/ml, p=0.01) and IGF-I/IGFBP-3 ratio (0.14±0.05 vs. 0.17±0.04, p=0.04). Compared to controls, MHL subjects had lower total IGF-I (153±54 ng/ml, p=0.0002) and IGFBP-3 (2.8±0.6 mg/ml, p<0.0001), but higher IGF-I/IGFBP-3 ratio (0.25±0.06, p<0.0001). Differences remained significant after the adjustment for clinical and biochemical covariates, except for triglycerides. Patients with both IHC and MHL have lower total IGF-I compared to controls. The mechanism is presumably different in IHC and MHL. Because of prominent reduction of IGFBP-3 in patients with MHL, they have reduced total IGF-I despite the actual elevation IGF-I/IGFBP-3 ratio as a surrogate of free IGF-I., J. Malík, T. Štulc, D. Wichterle, V. Melenovský, E. Chytilová, Z. Lacinová, J. Marek, R. Češka., and Obsahuje bibliografii a bibliografické odkazy
The presence of insulin resistance is frequently found in essential hypertension. There are, however, only sparse data with respect to the potential presence of insulin resistance in patients with secondary hypertension. We have therefore undertaken a study to reveal the potential occurrence of insulin resistance in primary hyperaldosteronism (PH). The hyperinsulinemic euglycemic clamp technique together with the evaluation of insulin receptor characteristics were used to study insulin resistance in 12 patients with PH. The measured parameters were compared to normal values in control subjects. We have found a significantly lower glucose disposal rate (M, m mol/kg/min) (18.7± 6 vs. 29.3± 4), decreased tissue insulin sensitivity index (M/I, m mol/kg/min per mU/l x100) (23.7± 9.8 vs. 37.5± 11.6) and also lower metabolic clearance rate of glucose (MCRg, ml/kg/min) (3.8± 1.5 vs. 7.0± 1.1) in patients with primary hyperaldosteronism. The insulin receptor characteristics on erythrocytes did not differ in primary hyperaldosteronism as compared to control healthy subjects. We thus conclude that insulin resistance is also present in secondary forms of hypertension (primary hyperaldosteronism) which indicates the heterogeneity of impaired insulin action in patients with arterial hypertension., J. Widimský Jr., G. Šindelka, T. Haas, M. Prázný, J. Hilgertová, J. Škrha., and Obsahuje bibliografii
Critical illness induces among other events production of proinflammatory cytokines that in turn interfere with insulin signaling cascade and induce insulin resistance on a postreceptor level. Recently, local renin-angiotensin system of adipose tissue has been suggested as a possible contributor to the development of insulin resistance in patients with obesity. The aim of our study was to determine local changes of the renin-angiotensin system of subcutaneous and epicardial adipose tissue during a major cardiac surgery, which may serve as a model of an acute stress potentially affecting endocrine function of adipose tissue. Ten patients undergoing elective cardiac surgery were included into the study. Blood samples and samples of subcutaneous and epicardial adipose tissue were collected at the beginning and at the end of the surgery. Blood glucose, serum insulin and adiponectin levels were measured and mRNA for angiotensinogen, angiotensin-converting enzyme and angiotensin II type 1 receptor were determined in adipose tissue samples using RT PCR. Cardiac surgery significantly increased both insulin and blood glucose levels suggesting the development of insulin resistance, while serum adiponectin levels did not change. Expression of angiotensinogen mRNA significantly increased in epicardial adipose tissue at the end of surgery relative to baseline but remained unchanged in subcutaneous adipose tissue. Fat expression of angiotensin-converting enzyme and type 1 receptor for angiotensin II were not affected by surgery. Our study suggests that increased angiotensinogen production in epicardial adipose tissue may contribute to the development of postoperative insulin resistance., T. Roubíček, M. Dolinková, J. Bláha, D. Haluzíková, L. Bošanská, M. Mráz, J. Křemen, M. Haluzík., and Obsahuje bibliografii a bibliografické odkazy
We studied the changes in seru m fibroblast growth factor-21 (FGF-21) concentrations, its mR NA, and protein expression in skeletal muscle and adipose tissue of 15 patients undergoing cardiac surgery. Blood samples were obtained: prior to initiation of anesthesia, prior to the start of extracorporeal circulation, upon completion of the surger y, and 6, 24, 48, and 96 hours after the end of the surgery. Tissue sampling was performed at the start and end of surgery. The mean baseline serum FGF-21 concentration was 63.1 (43.03-113. 95) pg/ml and it increased during surgery with peak 6 ho urs after its end [385.5 (274.55-761.65) pg/ml, p<0.001], and return ed to baseline value [41.4 (29.15-142.83) pg/ml] 96 hours afte r the end of the surgery. Serum glucose, insulin, CRP, IL-6, IL-8, MCP-1, and TNF-alpha concentrations significantly increased during the surgery. Baseline FGF-21 mRNA expression in skeletal muscle was higher than in both adipose tissue depots and it was not affected by the surgery. Epicardial fat FGF-21 mRNA increased after surgery. Muscle FGF-21 mRNA positively correlated with blood glucose levels at the end of the surgery. Our data suggest a possible role of FGF-21 in the regulation of glucose metabolism and insulin sensitivity in surgery-related stress., T. Kotulák ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Lipoprotein (a) [Lp(a)] is an LDL-like particle that contains an apolipoprotein B100 molecule covalently bound to a plasminogen-like glycoprotein, apolipoprotein (a) [apo(a)]. Epidemiological evidence supports a direct and causal association between Lp(a) levels and coronary risk. On the contrary, a few prospective findings demonstrate inverse association of Lp(a) levels with risk of type 2 diabetes (T2DM). The aim of our study was to evaluate the association of Lp(a) with indicators of insulin resistance (IR) and metabolic syndrome (MS), which precede development of T2DM. We enrolled 607 asymptomatic dyslipidemic subjects (295 men and 312 women, mea n age 45.6±14.0 years) into our cross-sectional study. Lp(a) concentrations correlated inversely with TG, AIP, insulin, HOMA, C-peptide, BMI, waist circumference, and number of MS components (p<0.01 for all). Subjects with MS had significantly lower Lp(a) concentrations in comparison with those without the presence of this phenotype (p<0.0001). Serum concentrations of Lp(a) in the lower (1th 3rd) quartiles of insulin and HOMA were significantly higher than in the 4 th quartile of these insulin resistance markers (p<0.001). Odds ratios of having increased markers of IR (TG, HOMA) and MS in top quartile of Lp(a) also indicate inverse association of Lp(a) with IR. The results of our study support an inverse association of Lp(a) levels with IR and MS that precedes overt T2DM diagnosis., H. Vaverková, D. Karásek, M. Halenka, L. Cibíčková, V. Kubíčková., and Obsahuje bibliografii
Lipasin is a recently identified lipokine expressed predominantly in liver and in adipose tissue. It was linked to insulin resistance in mice and to type 1 and type 2 diabetes (T1D, T2D) in humans. No metabolic studies concerning lipasin were performed yet in rats. Therefore, we used rat model of T2D and insulin resistance, Goto-Kakizaki (GK) rats, to determine changes of lipasin expression in liver and in white adipose tissue (WAT) over 52 weeks in the relation to glucose tolerance, peripheral tissue insulin sensitivity and adiposity. GK rats were grossly glucose intolerant since the age of 6 weeks and developed peripheral insulin resistance at the age of 20 weeks. Expression of lipasin in the liver did not differ between GK and Wistar rats, declining with age, and it was not related to hepatic triacylglycerol content. In WAT, the lipasin expression was significantly higher in Wistar rats where it correlated positively with adiposity. No such correlation was found in GK rats. In conclusion, lipasin expression was associated neither with a mild age-related insulin resistance (Wistar), nor with severe genetically-based insulin resistance (GK)., M. Cahová, D. Habart, T. Olejár, Z. Berková, Z. Papáčková, H. Daňková, A. Lodererova, M. Heczková, F. Saudek., and Obsahuje bibliografii
It has been suggested that thiazolidinediones (TZDs) ameliorate insulin resistance in muscle tissue by suppressing muscle lipid storage and the activity of novel protein kinase C (nPKC) isoforms. To test this hypothesis, we analyzed long-term metabolic effects of pioglitazone and the activation of nPKC-ε and -θ isoforms in an animal model of the metabolic syndrome, the spontaneously hypertensive rat (a congenic SHR strain with wild type Cd36 gene) fed a diet with 60 % sucrose from the age of 4 to 8 months. Compared to untreated controls, pioglitazone treatment was associated with significantly increased basal (809±36 vs 527±47 nmol glucose/g/2h, P<0.005) and insulinstimulated glycogenesis (1321±62 vs 749±60 nmol glucose/g/2h, P<0.0001) in isolated gastrocnemius muscles despite increased concentrations of muscle triglycerides (3.83±0.33 vs 2.25±0.12 μmol/g, P<0.005). Pioglitazone-treated rats exhibited significantly increased membrane/total (cytosolic plus membrane) ratio of both PKC-ε and PKC-θ isoforms compared to untreated controls. These results suggest that amelioration of insulin resistance after long-term pioglitazone treatment is associated with increased activation of PKC-ε and -θ isoforms in spite of increased lipid concentration in skeletal muscles., I. Marková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Diabetická retinopatie (DR) je typickou mikrovaskulární komplikací diabetu 1. i 2. typu. Ve vyspělých zemích je nejčastější příčinou slepoty u osob v produktivním věku. Základní metabolickou odchylkou, která hraje nejdůležitější roli při jejím vzniku, je hyperglykemie. Hyperglykemie zvyšuje mitochondriální produkci reaktivních kyslíkových radikálů a oxidační stres, vede k hromadění pokročilých produktů glykace (AGE), tvorbě hexosaminu, akcentaci polyolové cesty a zvýšení osmoticky aktivního sorbitolu, a ke zvýšení proteinkinazy C (PKC). Závažnost vaskulární patologie je významně ovlivněna genetickou dispozicí jedince a je modifikována dalšími metabolickými a hemodynamickými faktory. Tyto podněty aktivují intracelulární signální molekuly, jako je protein kinázy B (Akt kináza), mitogeny aktivovaná protein kináza (MAPK), cyklin-dependentní kinázy či nukleární faktor-?B (NF-?B). Uvedené abnormity ovlivní nejprve funkci a později i morfologii celé řady cílových buněk, které zahrnují nejen buňky orgánu vlastní (endotelové buňky, pericyty, neurony, glie, pigmentový epitel), ale také imunokompetentní buňky, které infiltrují do místa patologie z cévního řečiště (nonrezidentní buňky). Aktivované buňky pak vedou k produkci řady mediátorů s vazoaktivními a růstovými vlastnostmi. Výsledkem je komplex, zpočátku funkčních a později strukturálních změn, které se projeví v dysregulaci a) krevního průtoku, b) buněčného růstu (apoptóza, proliferace, hypertrofie) a vedou k c) proliferaci vaziva, zmnožení extracelulární hmoty ztluštění bazálních membrán. Důsledkem je pak rozvoj morfologicky fixované orgánové patologie. Poznání patofyziologických mechanizmů rozvoje DR dává naději na možnou kauzální léčbu a prevenci., Terezie Pelikánová, and Lit. 43
Retinol binding protein 4 (RBP4) is a novel adipokine which might be involved in the development of insulin resistance. The aim of the study was to investigate the expression of RBP4 mRNA in subcutaneous and visceral fat depots and the relationship between RBP4 plasma and mRNA levels relative to indices of adiposity and insulin resistance. In 59 Caucasian women (BMI 20 to 49 kg/m2 ) paired samples of subcutaneous and visceral fat were obtained for RBP4, leptin and GLUT 4 mRNA analysis using reverse transcription-quantitative PCR. Euglycemic hyperinsulinemic clamp and computed tomography scans were performed. RBP4 mRNA levels as well as GLUT 4 mRNA and leptin mRNA levels were lower (P<0.001, P<0.01 and P<0.001, respectively) in visceral compared to subcutaneous fat. No differences were found in RBP4 mRNA expression in the two fat depots or in RBP4 plasma levels between subgroups of non-obese subjects (n=26), obese subjects without metabolic syndrome (n=17) and with metabolic syndrome (n=16). No correlations between RBP4 mRNA or plasma levels relative to adiposity, glucose disposal rate and GLUT 4 mRNA expression in adipose tissue were found. There was a weak positive correlation between plasma RBP4 and plasma triglycerides (r = 0.30, p<0.05) and between plasma RBP4 and blood glucose (r = 0.26, p<0.05). Regardless of the state of adiposity or insulin resistance, RBP4 expression in humans was lower in visceral than in subcutaneous fat. We found no direct relationship between either RBP4 mRNA or its plasma levels and the adiposity or insulin resistance. and Obsahuje bibliografii a bibliografické odkazy
Úvod: Scintigrafie je optimální metodou pro molekulární zobrazování, je tedy vhodná pro vyšetřování pacientů s me-tabolickými poruchami. Diabetická kardiomyopatie se klinicky projevuje jako srdeční selhání bez přítomnosti koronární aterosklerózy, hypertenze či chlopenní vady. Její příčina není zcela objasněna, nejspíše je multifaktoriální s podílem poruchy buněčného metabolismu včetně inzulinové rezistence, poškození mikrocirkulace či endoteliální dysfunkce, autonomní neuropatie a intersticiální fibrózy. Materiál a metody: Scintigrafie umožňuje sledovat řadu patofyziologických mechanismů, které se mohou na rozvoji diabetické kardiomyopatie podílet. V experimentu se jedná především o poruchy buněčného metabolismu. Ze substrátů lze použít glukózu, mastné kyseliny, acetát. Scintigrafické metody jsou také vhodné pro diagnostiku poruchy mikrocirkulace s následnou poruchou prokrvení myokardu. K tomu slouží zejména perfuzní radiofarmaka nejvíce používaná v rutinní klinické praxi. Pro vyšetřování poruch autonomní inervace se používají metabolická analoga noradrenalinu nebo přímé značení katecholaminů. Výsledky: U diabetiků je narušena metabolická plasticita myokardu, snižuje se schopnost utilizace glukózy se zvýšeným hromaděním mastných kyselin. To má za následek poruchu funkce myocytů. Jednak dochází ke snížení produkce energie se snížením kontraktility, jednak se zvyšuje lipotoxicita vedoucí až k apoptóze s následnou fibrózou myokardu. Prokázaná porucha prokrvení myokardu se vyskytuje u 20 - 40 % asymptomatických diabetiků. Rovněž se u diabetiků prokázala snížená vasodilatační kapacita i bez postižení epikardiálních tepen. U diabetiků byla rovněž prokázaná změna regionální distribuce sympatické inervace v myokardu levé komory. Závěr: Scintigrafické metody mají velký diagnostický potenciál. Mohou umožnit včasné zahájení efektivní léčby. V klinické praxi se však musí používat uvážlivě a cíleně zejména u symptomatických a vysoce rizikových pacientů., x, Otto Lang, and Literatura
Our aim was to assess the reaction of TNFα, resistin, leptin and adiponectin to lipid infusion. Eight healthy subjects underwent a 24-hour lasting infusion of lipid emulsion. Plasma concentrations and expressions of selected cytokines in subcutaneous fat were measured. TNFα plasma concentration did not change during the first 4 hours of hypertriglyceridemia, but a significant increase after 24 hours was detected (p<0.001 for 0; 30; 240 min vs. 24 h). Plasma concentration of resistin significantly increased at 30 min of infusion and remained elevated (p<0.01 for 0 min vs. 30; 240 min; p<0.001 for 0 min vs. 24 h). Plasma concentrations of leptin and adiponectin did not show any significant changes. Although the expression of resistin in the subcutaneous adipose tissue tended to increase, the change was not significant. Expressions of TNFα, leptin and adiponectin were unaffected. In conclusions, our results indicate that acutely induced hyperlipidemia could influence the secretion of TNFα and resistin., J. Kopecký ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Je rozdiel v sérovej hladine retinol-binding proteinu 4 (RBP4) medzi obéznymi s inzulínovou rezistenciou (IR) bez diabetu voči obéznym s diabetom 2. typu (DM2T) liečených metformínom a neobéznymi zdravými? Metodika: 28 obéznym s inzulínovou rezistenciou, 11 diabetikom 2. typu liečených metformínom a 17 kontrolám sa metódou RIA vyšetrila sérová hladina retinol-binding proteinu 4. Výsledky sa porovnali v rámci skupín a RBP4 sa v skupine s IR a v kontrolnej skupine koreloval s inzulínom. Výsledky: Najvyššiu hladinu RBP4 (561,6 ? 209 ng/ml) mali obézni s IR (IR HOMA 3,9) a najnižšiu obézni diabetici typu 2 liečení metformínom (391,1 ? 133,5 ng/ml; p < 0,01). Kontrolná skupina mala signifikantne nižšiu hladinu RBP4 voči obéznym s IR (452,8 ? 104,6 ng/ml; p < 0,05), ale nesignifikantne vyššiu voči obéznym jedincom s DM2T liečených metformínom (391,1 ? 133,5 ng/ml). RBP4 v sledovanej skupine koreloval s inzulínom r = 0,46 (p < 0,03). Záver: Zvýšenie RBP4 u obéznych cestou spätnej regulácie GLUT4 v adipocytoch prispieva k rozvoju a k zhoršeniu systémovej IR metformín vplyvom na expresiu RBP4 v adipocytoch môže u obéznych aj s MS zlepšovať celkovú inzulínovú senzitivitu a spomaliť nástup manifestného DM. RBP4 by mohol slúžiť aj ako marker zhoršujúcej sa tolerancie glukózy u obéznych., Mária Tajtáková, Z. Semanová, G. Ivančová, and Lit. 26
Diabetes mellitus postihuje přibližně 4 % žen, u kterých v průběhu života dochází k interakci diabetu, jeho léčby a přirozených změn pohlavních hormonů (dětství, puberta, reprodukční období, gravidita, klimakterium). Přehledový článek shrnuje dosud publikovanou literaturu ke vzájemnému vztahu diabetu a pohlavního vývoje u žen., Approximately 4 % of female population suffers from diabetes. A permanent interaction between diabetes, its treatment and sex hormonal changes (childhood, puberty, reproduction, pregnancy, menopause) occurs in those women. This review article summarizes up to date published studies concerning reciprocal relationship between diabetes and sexual development in women., and Ludmila Brunerová, Jan Brož
Diabetes mellitus postihuje přibližně 4 % žen, u kterých v průběhu života dochází k interakci diabetu, jeho léčby a přirozených změn pohlavních hormonů (dětství, puberta, reprodukční období, gravidita, klimakterium). Přehledový článek shrnuje dosud publikovanou literaturu ke vzájemnému vztahu diabetu a pohlavního vývoje u žen. Klíčová slova: diabetes mellitus – gestace – hormonální kontracepce – hyperandrogenizmus – menopauza – pohlavní hormony – puberta, Approximately 4 % of female population suffers from diabetes. A permanent interaction between diabetes, its treatment and sex hormonal changes (childhood, puberty, reproduction, pregnancy, menopause) occurs in those women. This review article summarizes up to date published studies concerning reciprocal relationship between diabetes and sexual development in women. Key words: diabetes mellitus – gestation – hormonal contraceptive – hyperandrogenism – menopause – puberty – sex hormones, and Ludmila Brunerová, Jan Brož
Syndrom polycystických ovarií (PCOS) je v současné době doporučeno diagnostikovat podle tzv. ESHRE kritérií. Pro diagnózu podle nich stačí dva z následujících 3 symptomů: 1. morfologický obraz polycystických ovarií, 2. klinické projevy hyperandrogenizmu anebo laboratorní průkaz hyperandrogenemie a 3. oligo-anovulace. PCOS je komplexní onemocnění, v jehož patogenezi interagují genetické vlivy a vlivy prostředí. Nejde jen o gynekologické onemocnění, syndrom je doprovázený inzulinovou rezistencí, což vede ke zvýšenému výskytu diabetes mellitus 2. typu a porušené glukózové tolerance (4krát a 2krát, nezávisle na BMI). Také se častěji vyskytuje gestační diabetes mellitus. Dále je častější dyslipidemie, arteriální hypertenze, elevace CRP a homocysteinu, porucha funkce endotelu a silnější intima-media. Není však zcela jasné, zda jsou u žen s PCOS častější také kardiovaskulární příhody. PCOS je častěji, než je náhodné, asociován s depresí, anxiózními stavy, poruchami příjmu potravy, dále s nealkoholickou steatohepatitidou a se syndromem spánkové apnoe – zejména u obézních žen. Z léčebných opatření máme k dispozici nefarmakologické metody – u obézních úpravu životního stylu zaměřenou na redukci hmotnosti, u kožních projevů hyperandrogenizmu kosmetická opatření, zejména laserovou terapii a farmakoterapii (kombinovaná hormonální kontraceptiva a antiandrogeny). Poruchy menstruačního cyklu můžeme řešit kontraceptivy nebo cyklicky podávanými gestageny, uplatní se i metformin., For diagnosing of polycystic ovary syndrome (PCOS) it is currently recommended to follow the ESHRE criteria. For diagnosis according to them two of the following three symptoms are sufficient: 1. morphology of polycystic ovaria, 2. clinical manifestations of hyperandrogenism or laboratory proof of hyperandrogenemia, and 3. oligo-anovulation. PCOS is a complex disorder in whose pathogenesis genetic and environmental effects interact. It is not a gynecological disorder alone, the syndrome is accompanied by insulin resistance which leads to increased incidence of type 2 diabetes mellitus and impaired glucose tolerance (4 times and twice, independently of BMI). Also gestational DM occurs more frequently. Dyslipidemia, arterial hypertension, elevated CRP and homocysteine levels, endothelial dysfunction and greater intima-media thickness are also more frequent. It is not quite clear, however, whether women with PCOS suffer cardiovascular events more frequently as well. More often than is accidental PCOS is associated with depression, anxiety and eating disorders, further with nonalcoholic steatohepatitis and with the sleep apnoea syndrome – especially in obese women. Therapeutic measures include non-pharmacological methods – lifestyle adjustments focused on weight reduction in obese individuals, cosmetic measures for dermatologic manifestation of hyperandrogenism, in particular laser and pharmacotherapy (combined hormonal contraceptives and antiandrogens). Menstrual irregularities can be treated with contraceptives or cyclical administration of gestagens, also metformin can be used., and Jana Vrbíková
Syndrom polycystických ovarií (PCOS) se považuje za jednu z nejčastěji se vyskytujících endokrinopatií u žen ve fertilním věku. Ženy trpící PCOS jsou ve 30–80 % současně obézní a obezita je často doprovázena hyperinzulinemií a inzulinovou rezistencí, a to i nezávisle na BMI. Většina publikovaných prací prokazuje u žen s PCOS zvýšený výskyt diabetes mellitus 2. typu. U žen s PCOS je 2,89krát vyšší riziko vzniku gestačního diabetu nežli u kontrolních pacientek. Doporučuje se proto provádět screening orálním glukózovým tolerančním testem. Prvním opatřením v péči o obézní pacientky s PCOS je úprava životního stylu, byť chybí pro toto opatření opora v dostatečném množství kontrolovaných studií na toto téma. Pokud nedojde k úpravě porušené glukózové tolerance, je indikován metformin, u nějž ovšem také chybí dostatek údajů o podávání gravidním s cílem prevence rozvoje GDM. PCOS se ovšem vyskytuje až u 30 % žen s diabetes mellitus 1. typu a bývá spojován s terapií inzulinem. Dosavadní pilotní studie prokazují, že se v terapii příznivě uplatňuje metformin, a u žen, které nechtějí otěhotnět, kombinovaná hormonální kontraceptiva s neandrogenními gestageny. Klíčová slova: diabetes mellitus – gestageny – kombinovaná hormonální kontraceptiva – metformin – orální glukózový toleranční test – porušená glukózová tolerance – syndrom polycystických ovarií, Polycystic ovary syndrome (PCOS) is considered one of the most common endocrinopathies in women of childbearing age. 30 – 80 % of women suffering from PCOS are obese and obesity is often accompanied by hyperinsulinemia and insulin resistance, even independently of body mass index. Most of the published works have demonstrated an increased incidence of type 2 diabetes in women with PCOS. There is 2,89 times higher risk of developing gestational diabetes in women with PCOS comparing to control group. Therefore, it is recommended to perform oral glucose tolerance test. It is highly recommended to begin with lifestyle changes as the first step in treating obese woman with PCOS although there is lack of evidence from controlled trials. If impaired glucose tolerance does not improve, metformin is indicated, but there is lack of data on the use in pregnant women as a prevention of GDM development. PCOS occurs in up to 30% of women with type 1 diabetes and is associated with insulin therapy. The existing pilot studies have demonstrated that metformin is useful in therapy. The combined hormonal contraceptives with non-androgenic gestagens are applied in women who do not want to be pregnant. Key words: combined hormonal contraceptives – diabetes mellitus – gestagens – impaired glucose tolerance – metformin – oral glucose tolerance test – polycystic ovary syndrome, and Jana Vrbíková
Bradykinin can enhance skeletal muscle glucose uptake (GU), and exercise increases both br adykinin production and muscle insulin sensitivity, but bradykinin’s relationship with post-exercise insulin action is uncertain. Our primary aim was to determine if the B2 receptor of bradykinin (B2R) is essential for the post- exercise increase in GU by insulin-stimulated mouse soleus muscles. Wildtype (WT) and B2 R knockout (B2RKO) mice were sedentary or performed 60 minutes of treadmill exercise. Isolated soleus muscles were incubated with [ 3 H]-2-deoxyglucose ±insulin (60 or 100 μ U/ml). GU tended to be greater for WT vs. B2RKO soleus with 60 μ U/ml insulin (P=0.166) and was significantly greater for muscles with 100 μ U/ml insulin (P<0.05). Both genotypes had significant exercise-induced reductions (P<0.05) in glycemia and insulinemia, and the decrements for glucose (~14 %) and insulin (~55 %) were similar between genotypes. GU tended to be greater for exercised vs. sedentary soleus with 60 μ U/ml insulin (P=0.063) and wa s significantly greater for muscles with 100 μ U/ml insulin (P<0.05). There were no significant interactions between genotype and exercise for blood glucose, plasma insulin or GU. These results indicate that the B2R is not essential for the exerci se-induced decrements in blood glucose or plasma insulin or for the post-exercise increase in GU by insulin-stimulated mouse soleus muscle., G. G. Schweitzer ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
We explored the effect of chronically elevated circulating levels of growth hormone (GH)/insulin -like -growth- factor-1 (IGF-1) on mRNA expression of GH/IGF-1/insulin axis components and p85alpha subunit of phosphoinositide -3-kinase (p85alpha) in subcutaneous adipose tissue (SCAT) of patients with active acromegaly and compared these findings with healthy control subjects in order to find its possible relationships with insulin resistance and body composition changes. Acromegaly group had significantly decreased percenta ge of truncal and whole body fat and increased homeostasis model assessment-insulin resistance (HOMA -IR). In SCAT, patients with acromegaly had significantly increased IGF-1 and IGF -binding protein-3 (IGFBP-3) expression that both positively correlated wit h serum GH. P85alpha expression in SCAT did not differ from control group. IGF-1 and IGFBP-3 expression in SCAT were not independently associated with percentage of truncal and whole body fat or with HOMA -IR while IGFBP -3 expression in SCAT was an independ ent predictor of insulin receptor as well as of p85alpha expression in SCAT. Our data suggest that GH overproduction in acromegaly group increases IGF-1 and IGFBP-3 expression in SCAT while it does not affect SCAT p85alpha expression. Increased IGF-1 or IGFBP-3 in SCAT of acromegaly group do not appear to contribute to systemic differences in insulin sensitivity but may have local regulatory effects in SCAT of patients with acromegaly., V. Touskova, J. Klouckova, V. Durovcova, Z. Lacinova, P. Kavalkova, P. Trachta, M. Kosak, M. Mraz, D. Haluzikova, V. Hana, J. Marek, M. Krsek, M. Haluzik., and Obsahuje bibliografii
The skin matrix metalloproteinase 3, tissue inhibitors of matrix metalloproteinase 2 and collagen III content changes in type 1 diabetes and insulin resistance treated with insulin a nd metformin were studied. Healthy adult male Wistar rats were obtained from experimental animal house, Department of Experimental Pharmacology, Medical University in Bialystok. The rats were divided randomly into five groups of 8 rats each. Control rats were injected intraperitoneally by NaCl. Type IDDM was induced by a single injection of Streptozocin. Insulin resistance was induced by a high -fat diet. The chosen groups of rats were also treated with insulin or metformin. ELISA K its (USCN Life Science, China) were used to measure content of matrix metallo - proteinase 3 (ELISA Kit for Matrix Metalloproteinase 3 - MMP3), tissue inhibitor of matrix metalloproteinase 2 (ELISA Kit for Tissue Inhibitors of Metalloproteinase 2 - TIMP2) and content of collagen type 3 (ELISA Kit for Collagen Type III - COL3). The results were reported as a median. The statistical significance was defined as p<0.05. Type 1 diabetes and insulin resistance have significantly reduced the quality of the skin, shown by the increase in cont ent of matrix metalloproteinase 3 and the decrease in content of tissue inhibitors of matrix metalloproteinase 2. Type 1 diabetes and insulin resistance have reduced the quality of the skin expressed by type III collagen content decrease but for future studies it is recommend to determine rat interstitial collagenase, MMP -13, as well. Insulin and metformin treatment improved the quality of the diabetic skin, demonstrated by the type III collagen content increase., M. Knaś, K. Wołosik, A. Zalewska, A. Mikucka-Niczyporuk, I. Kasacka, M. Niczyporuk., and Obsahuje bibliografii
Spontaneously hypertensive rats (SHR/NIH strain) harbor a deletion variant in the Cd36 fatty acid transporter and display defective fatty acid metabolism, insulin resistance and hypertension. Transgenic rescue of Cd36 in SHR ameliorates insulin resistance and improves dyslipidemia. However, the role of Cd36 in blood pressure regulation remains controversial due to inconsistent blood pressure effects that were observed with transgenic expression of Cd36 on the SHR background. In the current studies, we developed two new SHR transgenic lines, which express wild type Cd36 under the control of the universal Ef-1 promoter, and examined the effects of transgenic expression of wild type Cd36 on selected metabolic and cardiovascular phenotypes. Transgenic expression of Cd36 in the new lines was associated with significantly decreased serum fatty acids, amelioration of insulin resistance and glucose intolerance but failed to induce any consistent changes in blood pressure as measured by radiotelemetry. The current findings confirm the genetic association of defective Cd36 with disordered insulin action and fatty acid metabolism in the SHR/NIH strain and suggest that Cd36 is linked to other gene(s) on rat chromosome 4 that regulate blood pressure., M. Pravenec, V. Landa, V. Zídek, A. Musilová, L. Kazdová, N. Qi, J. Wang, E. St.Lezin, T. W. Kurtz., and Obsahuje bibliografii
Cíl: Gen pro adiponektin bývá označován jako kandidátní gen inzulinové rezistence (IR). V naší práci byl sledován možný vztah mezi jednonukleotidovým polymorfi smem (SNP) +276 G > T a markery inzulinové rezistence včetně lipidového a lipoproteinového profi lu u 355 dyslipidemických pacientů lipidové ambulance III. interní kliniky Fakultní nemocnice Olomouc a jejich prvostupňových příbuzných. Metody: SNP genu pro adiponektin byl detekován metodou polymerázové řetězové reakce v reálném čase s hybridizačními fl uorescenčními sondami. Rozdíly mezi genotypy ve spojitých proměnných byly analyzovány metodou ANOVA (upraveno na věk, pohlaví a obvod pasu). Výsledky: Nosiči genotypu GG měli významně vyšší hladiny celkového cholesterolu (GG: 6,54 ± 1,74 mmol/l, GT: 6,18 ± 1,45 mmol/l, TT: 6,25 ± 1,64 mmol/l, p < 0,05) a LDL cholesterolu (GG: 4,12 ± 1,49 mmol/l, GT: 3,78 ± 1,31 mmol/l, TT: 3,70 ± 1,34 mmol/l, p < 0,05) než jedinci s alelou T. Přítomnost alely T na pozici 276 byla u heterozygotů naopak spojena s vyšší koncentrací inhibitoru aktivátoru plasminogenu 1 (PAI-1) (GG: 71,50 ± 41,0 μg/l, GT: 81,0 ± 38,7 μg/l, TT: 70,14 ± 44,4 μg/l, p < 0,05). Závěr: Ve studii byla zjištěna slabá asociace heterozygotů-nosičů T alely polymorfi smu +276 G > T genu pro adiponektin a jedním markerem inzulinové rezistence, avšak nebyl nalezen vztah k sérovému adiponektinu, inzulinu, body mass indexu a dyslipidemickým fenotypům., Aim: The adiponectin gene has been proposed as a potential candidate gene for IR. We analysed possible relationship between +276 G > T SNP and IR markers together with lipid and lipoprotein profi les in 355 Czech dyslipidemic patients of Lipid Center, University Hospital Olomouc, and their fi rst degree relatives. Methods: The +276 G > T SNP of adiponectin gene was detected by real time PCR method with hybridization fl uorescence probes in LightCycler. Between-genotype differences in continuous variables were analyzed by ANOVA after adjustment for age, sex and waist circumference. Results: Subjects with GG genotype were associated with higher total cholesterol (GG: 6.54 ± 1.74 mmol/l, GT: 6.18 ± 1.45 mmol/l, TT: 6.25 ± 1.64 mmol/l, p < 0.05) and LDL cholesterol (GG: 4.12 ± 1.49 mmol/l, GT: 3.78 ± 1.31 mmol/l, TT: 3.70 ± 1.34 mmol/l, p < 0.05) in comparison with T allele carriers. On the contrary, the presence of T allele in position 276 in heterozygotes was associated with higher levels of plasma inhibitor of activator of plasminogen 1 (PAI-1) (GG: 71.50 ± 41.0 μg/l, GT: 81.0 ± 38.7 μg/l, TT: 70.14 ± 44.4 μg/l, p < 0.05). Conclusion: In this study, the poor association between carriers- heterozygotes of T alelle of +276 G > T polymorphism of gene for adiponectin and one marker of insulin resistance was found. However, no relationship was detected with plasma adiponectin, insulin, body mass index and dyslipidemic phenotypes., Novotný Dalibor, Vaverková H., Karásek D., Halenka M., Lukeš J., Slavík L., Bartková M., Schneiderka P., and Lit.: 11
Zásah porušené regulace metabolizmu glukózy do metabolizmu kostní tkáně je mnohostranný a velmi komplikovaný. Ve většině případů nacházíme u diabetiků zvýšené riziko zlomenin. Důvody, které k tomuto stavu vedou, jsou mnohočetné. U diabetiků nebývá hlavní příčinou pokles kostní minerální hustoty, spíše jde o snížení kvality kostní tkáně a změnu její struktury. Významnou roli hraje nepochybně inzulin a inzulinová rezistence, uplatňuje se ale i zvýšená glykace proteinů, včetně zvýšené glykace kolagenu v kostech, změna produkce a hladiny sklerostinu, zásah do diferenciace pluripotentních kmenových buněk a zvrat jejich diferenciace směrem k adipocytům a mnohé další faktory. Nemalý podíl na zvýšeném riziku fraktur mohou mít i některá antidiabetika, především perorální. Vzhledem ke stoupající incidenci obou chorob, diabetu i osteoporózy, bude nezbytné podrobněji zkoumat i jejich vzájemné vazby a ovlivnění. Klíčová slova: antidiabetika – diabetes mellitus – inzulinová rezistence – metabolizmus kostí – osteoporóza, The effect of impaired regulation of the glucose metabolism on the bone tissue metabolism is many-sided and very complicated. In most cases we observe an increased risk of fracture in people with diabetes. The reasons causing this condition are varied. Its main cause in diabetic patients is typically not the decrease in bone mineral density, it is rather deterioration of bone tissue and its structure. An important role of insulin and insulin resistance is beyond dispute, with numerous other factors at work, such as increased glycation of proteins, including increased glycation of collagen in bones, change in sclerostin production and levels, intervention in the pluripotent stem cells differentiation and reversal of their differentiation toward adipocytes and many more. Some antidiabetics, mainly oral, may also significantly contribute to the increased risk of fracture. Given the increasing incidence of both diseases, diabetes and osteoporosis, it will be also necessary to examine in greater detail their mutual relations and effects. <p align="">Key words: antidiabetics – bone metabolism – diabetes mellitus – insulin resistance – osteoporosis, and Vladimír Palička, Jana Lesná, Ladislava Pavlíková