The novel myokine irisin has been reported as a therapeutic target for metabolic disease. The objective of this study is to reveal the effects of aerobic training (AT) and resistance training (RT) on circulating irisin levels and their associations with change of body composition in overweight/obese adults. Twenty eight overweight/obese adults (BMI>23 kg/m2) were included in this study and compared before and after 8 weeks of exercise program (60 min/day, 5 times in a week). The subjects, in both aerobic and resistance training, showed significant improvement in anthropometric parameters and exercise capacities including maximal oxygen uptake and muscle strength. Interestingly, the circulating irisin was significantly increased in resistance training group (p=0.002) but not in aerobic training (p=0.426) compared to control group. In addition, we found the positive correlation between change of the circulating irisin and muscle mass (r=0.432, p=0.022) and the negative correlation between change of the circulating irisin and fat mass (r=-0.407, p=0.031). In the present pilot study, we found that circulating irisin level was increased by 8 weeks of resistance training in overweight/obese adults, suggesting that resistance training could be the efficient exercise type in overweight/obese considering positive change of body composition concomitant with increase of irisin levels., Hee-Jae Kim, Hyo-Joo Lee, Byunghun So, Jun Seok Son, Donghyun Yoon, Wook Song., and Obsahuje bibliografii
a1_In the present work the effects of fasting and refeeding on fat pad weight and alkaline phosphatase activity in the brush border of individual duodenal enterocytes have been evaluated in male Wistar rats with obesity induced by monosodium glutamate (MSG) treatment during the early postnatal period. Neonatal rats were treated subcutaneously with MSG (2 mg/g b.w.) or saline (controls) for 4 days after birth. At 4 months of age, two types of experiments were performed. In the first experiment rats, were submitted to 3 or 6 days lasting food deprivation. In the second experiment the rats were refed for 3 or 6 days ad libitum or restrictedly (60 % of pre-fasting intake) after a 6 day-fasting period. Fasting and refeeding influenced the body fat and function of the duodenum in MSG-treated rats differently as compared to the controls. However, alkaline phosphatase activity and the weight of epididymal and retroperitoneal fat depots were significantly increased in MSG obese rats (P<0.001) during all the periods examined. While 3 days of food deprivation resulted in both groups in a similar loss of adipose tissue weight and alkaline phosphatase activity, the decrements of these parameters after 6 days of fasting were lower in obese rats suggesting that their capacity to spare body fat stores was enhanced. After 3 days of ad libitum refeeding, a more marked adaptational increase of food consumption and also a significantly increased alkaline phosphatase activity above the pre-fasting level (P<0.01) was observed in the MSG-treated rats. Consequently, a more rapid body fat restoration was demonstrated in these animals. Refeeding of rats at 60 % of the pre-fasting intake level resulted in a significant increase of alkaline phosphatase activity in both the MSG and control group; moreover, as food restriction continued, MSG-treated rats tended to further increase the enzyme activity., a2_Our results revealed that MSG treatment of neonatal rats may significantly change the intestinal functions. Permanently increased alkaline phosphatase activity observed in MSG obese rats during all investigated periods suggests that this functional alteration is probably not a consequence of actual nutritional variation but could be a component of regulatory mechanisms maintaining their obesity at critical values., Ľ. Raček, Ľ. Lenhardt, Š. Mozeš., and Obsahuje bibliografii
Obesity in T1DM patients is associated with the components of metabolic syndrome. The influence of controlled fasting and low calorie diet (LCD) on insulin sensitivity and glucose metabolism was studied in 14 obese patients with type 1 diabetes mellitus (T1DM) (42.6±9.4 years, BMI 32.4±2.1 kg m−2). Insulin sensitivity in obese T1DM patients was measured using a hyperinsulinemic-euglycemic clamp before fasting, immediately after 7 days of fasting, and after 21 days of LCD. Glucose oxidation and non-oxidative glucose disposal were measured before and during the clamp by indirect calorimetry. In the control group of 13 of non-obese T1DM patients (36.9±13.9 years, BMI 22.6±2.1 kg m−2), only one hyperinsulinemiceuglycemic clamp was performed. Obese T1DM patients lost 6.1±1.1 kg after fasting and maintained reduction in body weight after 21 days of LCD. Fasting transiently reduced insulinmediated glucose disposal in the clamp (from 9.69±1.48 to 6.78±1.21 mg min−1 kg−1, P<0.001). This was caused by reduced glucose oxidation after the fasting period (from 2.81±0.52 to 0.88±0.98 mg min−1 kg−1, P<0.001). We conclude that one week of fasting transiently decreased insulin-mediated glucose disposal in T1DM patients. This was caused by reduced glucose oxidation., F. Musil, ... [et al.]., and Obsahuje seznam literatury
The aim of this study was to explore the changes in the adipokines leptin and adiponectin in obese patients with type 1 diabetes mellitus (T1DM) who underwent seven days of fasting and 21 days of low-calorie diet (LCD). The plasma leptin and adiponectin concentrations were measured in 14 obese patients with T1DM at baseline, immediately after 7 days of fasting, and after 21 days of LCD. 13 non-obese patients with T1DM were studied only after an overnight fasting. Bioimpedance technique was used for determination of body composition. Obese T1DM patients lost 6.0 kg (6.0; 6.8) (median, 25 %; 75 %) and decreased their fat tissue after fasting and LCD. Plasma leptin in obese T1DM was significantly higher than in non-obese T1DM patients: 9.10 (5.06; 25.89) vs. 1.71 (1.12; 7.08) μg ∙ l-1 and transiently decreased immediately after fasting: 3.45 μg ∙ l-1 (1.47; 7.00), (P<0.05). Adiponectin/leptin ratio in obese T1DM was significantly lower than in non-obese T1DM patients: 0.67 (0.57; 1.49) vs. 3.50 (2.46; 6.30) ∙ 103 and transiently increased immediately after fasting: 2.22 (1.26; 3.24) ∙ 103, (P<0.05). We conclude that obese patients with T1DM are characterized by hyperleptinemia that is reduced by prolonged fasting, but only slightly affected by low calorie diet., F. Musil, V. Blaha, A. Ticha, R. Hyspler, M. Haluzik, J. Lesna, A. Smahelova, L. Sobotka., and Obsahuje bibliografii
As environmental and genetic components contribute to the PCOS expression, we compared levels of endocrine disruptors, steroid hormones, cytokines, and metabolic parameters in twenty healthy, nine normal-weight PCOS women, and ten obese PCOS women. Steroid hormones, bisphenols (BPA, BPS, BPF, BPAF) and parabens (methyl-, ethyl-, propyl-, butyl-, benzyl-parabens) were measured by liquid chromatography-tandem mass spectrometry. Differences between the groups were assessed using the Mann-Whitney U test. Spearman correlation coefficients were calculated for the individual parameters relationship. Significantly higher levels of BPA, anti-Müllerain hormone, lutropine, lutropine/folitropine ratio, testosterone, androstenedione, 7β-OH-epiandrosterone, and cytokines (IL-6, VEGF, PDGF-bb), were found in normal-weight PCOS women compared to controls. Between normal-weight and obese PCOS women, there were no differences in hormonal, but in metabolic parameters. Obese PCOS women had significantly higher insulin resistance, fattyliver index, triglycerides, cytokines (IL-2, IL-13, IFN-γ). In healthy, but not in PCOS, women, there was a positive correlation of BPA with testosterone, SHBG with lutropine, and folitropine, while testosterone negatively correlated with SHBG. In obese women with PCOS, insulin resistance negatively correlated with SHBG and estradiol. No differences were observed in the paraben exposure. Levels of BPA were higher in PCOS women, indicating its role in the etiology. Obesity significantly worsens the symptoms., Markéta Šimková, Jana Vítků, Lucie Kolátorová, Jana Vrbíková, Michala Vosátková, Josef Včelák, Michaela Dušková., and Obsahuje bibliografii
The incidence of metabolic syndrome increases in the developed countries, therefore biomedical research is focused on the understanding of its etiology. The study of exact mechanisms is very complicated because both genetic and environmental factors contribute to this complex disease. The ability of environmental fac tors to promote phenotype changes by epigenetic DNA modifications (i.e. DNA methylation, histone modifications) was demonstrated to play an important role in the development and predisposition to particular symptoms of metabolic syndrome. There is no doubt that the early life, such as the fetal and perinatal periods, is critical for metabolic syndrome development and therefore critical for prevention of this disease. Moreover, these changes are visible not only in individuals exposed to environmental factor s but also in the subsequent progeny for multiple generations and this phenomenon is called transgenerational inheritance. The knowledge of molecular mechanisms, by which early minor environmental stimuli modify the expression of genetic information, might be the desired key for the understanding of mechanisms leading to the change of phenotype in adulthood. This review provides a short overview of metabolic syndrome epigenetics., J. Kuneš, I. Vaněčková, B. Mikulášková, M. Behuliak, L. Maletínská, J. Zicha., and Obsahuje bibliografii
Obesity increases the incidence of hypogonadism in men, and hypogonadism in turn plays a role in obesity. One of the first mechanisms proposed to explain this was a hypothesis based on the principle that obese men have higher estrogen levels, and that increased estrogens provide feedback to the hypothalamicpituitary-testicular axis, reducing the secretion of gonadotropins and leading to a decrease of overall testosterone levels. This concept has since been questioned, though never completely disproven. In this study we compared hormone levels in three groups of men with differing BMI levels (between 18-25, 25-29, and 30-39), and found correlations between lowering overall testosterone, SHBG and increased BMI. At the same time, there were no significant changes to levels of free androgens, estradiol or the gonadotropins LH and FSH. These findings are in line with the idea that estrogen production in overweight and obese men with BMI up to 39 kg/m2 does not significantly influence endocrine testicular function., Luboslav Stárka, Martin Hill, Hana Pospíšilová, Michaela Dušková., and Obsahuje bibliografii
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
It is known that excessive sympathetic activity and oxidative stress are enhanced in obesity. This study aimed to clarify whether exercise training (ET) attenuates sympathetic activation and oxidative stress in obesity. The obesity was induced by highfat diet (HFD) for 12 weeks. Male Sprague-Dawley rats were assigned to four groups: regular diet (RD) plus sedentary (RD-S), RD plus ET (RD-ET), HFD plus sedentary (HFD-S), and HFD plus ET (HFD-ET). The rats in RD-ET and HFD-ET groups were trained on a motorized treadmill for 60 min/day, five days/week for 8 weeks. The sympathetic activity was evaluated by the plasma norepinephrine (NE) level. The superoxide anion, malondialdehyde and F2-isoprostanes levels in serum and muscles were measured to evaluate oxidative stress. The ET prevented the increases in the body weight, arterial pressure and white adipose tissue mass in HFD rats. The NE level in plasma and oxidative stress related parameters got lower in HFD-ET group compared with HFD-S group. We have found decreased mRNA and protein levels of toll-like receptor (TLR)-2 and TLR-4 by ET in HFD rats. These findings suggest that ET may be effective for attenuating sympathetic activation and oxidative stress in diet-induced obesity., G. Li, J.-Y. Liu, H.-X. Zhang, Q. Li, S.-W. Zhang., and Obsahuje bibliografii
Accumulation of adipose tissue in lower body lowers risk of cardiovascular and metabolic disorders. The molecular basis of this protective effect of gluteofemoral depot is not clear. The aim of this study was to compare the profile of expression of inflammation-related genes in su bcutaneous gluteal (sGAT) and abdominal (sAAT) adipose tissue at baseline and in response to multiphase weight-reducing dietary intervention (DI). 14 premenopausal healthy obese women underwent a 6 months’ DI consisting of 1 month very-low-calorie-diet (VLCD), subsequent 2 months’ low-calori e-diet and 3 months’ weight maintenance diet (WM). Paired samples of sGAT and sAAT were obtained before and at the end of VLCD and WM periods. mRNA expression of 17 genes (macrophage markers, cytokines) was measured using RT-qPCR on chip-platform. At baseline, there were no differences in gene expression of macrophage markers and cytokines between sGAT and sAAT. The dynamic changes induced by DI were similar in both depots for all genes except for three cytokines (IL6, IL10, CCL2) that differed in their response during weight maintenance phase. The results show that, in obese women, there are no major differences between sGAT and sAAT in expression of inflammation-related genes at baseline conditions and in response to the weight-reducing DI., L. Mališová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy