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902. Influence of PPAR-α agonist fenofibrate on insulin sensitivity and selected adipose tissue-derived hormones in obese women with type 2 diabetes
- Creator:
- Kateřina Anderlová, Radka Doležalová, Jitka Housová, Lenka Bošanská, Denisa Haluzíková, Jaromír Křemen, Jan Škrha, and Martin Haluzík
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- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, obezitologie, diabetes mellitus, inzulín, obesitology, insulin, fenofibrát, adiponektin, resistin, fenofibrate, adiponectin, 14, and 612
- Language:
- English
- Description:
- PPAR-α agonists improve insulin sensitivity in rodent models of obesity/insulin resistance, but their effects on insulin sensitivity in humans are less clear. We measured insulin sensitivity by hyperinsulinemic-isoglycemic clamp in 10 obese females with type 2 diabetes before and after three months of treatment with PPAR-α agonist fenofibrate and studied the possible role of the changes in endocrine function of adipose tissue in the metabolic effects of fenofibrate. At baseline, body mass index, serum glucose, triglycerides, glycated hemoglobin and atherogenic index were significantly elevated in obese women with type 2 diabetes, while serum HDL cholesterol and adiponectin concentrations were significantly lower than in the control group (n=10). No differences were found in serum resistin levels between obese and control group. Fenofibrate treatment decreased serum triglyceride concentrations, while both blood glucose and glycated hemoglobin increased after three months of fenofibrate administration. Serum adiponectin or resistin concentrations were not significantly affected by fenofibrate treatment. All parameters of insulin sensitivity as measured by hyperinsulinemic-isoglycemic clamp were significantly lower in an obese diabetic group compared to the control group before treatment and were not affected by fenofibrate administration. We conclude that administration of PPAR-α agonist fenofibrate for three months did not significantly affect insulin sensitivity or resistin and adiponectin concentrations in obese subjects with type 2 diabetes mellitus. The lack of insulin-sensitizing effects of fenofibrate in humans relative to rodents could be due to a generally lower PPAR-α expression in human liver and muscle., K. Anderlová, R. Doležalová, J. Housová, L. Bošanská, D. Haluzíková, J. Křemen, J. Škrha, M. Haluzík., and Obsahuje bibliografii a bibiografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
903. Inhibin B, follicle stimulating hormone, luteinizing hormone and testosterone during childhood and puberty in males: changes in serum concentrations in relation to age and stage of puberty
- Creator:
- Martin Chada, Richard Průša, Jiří Bronský, Karel Kotaška, Kateřina Kotrčová, Markéta Pechová, and Ludmila Lisá
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- Subject:
- Fyziologie člověka a srovnávací fyziologie, dětství, puberta, childhood, puberty, male, inhibin B, 14, and 612
- Language:
- English
- Description:
- Inhibin B is a gonadal dimeric polypeptide hormone that regulates synthesis and secretion of follicle stimulating hormone (FSH) in a negative feedback loop. The aim of the present study was to determine changes in serum inhibin B, gonadotropins and testosterone concentrations during childhood and puberty in males. We studied the relationship between circulating inhibin B, gonadotropins and testosterone in serum of healthy boys during the first two years of life and then in pubertal development. Using a recently developed two-side enzyme-linked immunosorbent assay (ELISA), inhibin B levels were measured in the serum of 78 healthy boys divided into eleven age groups from birth to the end of pubertal development. In addition, serum levels of gonadotropins and testosterone were measured. Serum inhibin B, gonadotropins and testosterone increased during the first months of postnatal life. A peak in serum inhibin B and gonadotropins concentrations was observed around 3-4 months of age. There was a significant positive correlation between serum inhibin B and gonadotropins and testosterone levels during the first 2 years of life. After this early increase, serum inhibin B, gonadotropins and testosterone levels decreased significantly and remained low until puberty followed by an increase beginning with the onset of puberty. Serum levels of inhibin B reached a peak at stage G3 of puberty. Around midpuberty, inhibin B lost its positive correlation with luteinizing hormone (LH) and testosterone from early puberty, and developed a strong negative correlation with FSH, which persisted into adulthood. We conclude that inhibin B plays a key role in the regulation of the hypothalamic-pituitary-gonadal hormonal axis during male childhood and pubertal development. Inhibin B is a direct marker of the presence and function of Sertoli cells and appears to reflect testicular function in boys., M. Chada, R. Průša, J. Bronský, K. Kotaška, K. Šídlová, M. Pechová, L. Lisá., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
904. Inhibin B, follicle stimulating hormone, luteinizing hormone, and estradiol and their relationship to the regulation of follicle development in girls during childhood and puberty
- Creator:
- Martin Chada, Richard Průša, Jiří Bronský, Markéta Pechová, Karel Kotaška, and Lidka Lisá
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- Subject:
- Fyziologie člověka a srovnávací fyziologie, dívky, dětství, puberta, girls, childhood, puberty, inhibin B, 14, and 612
- Language:
- English
- Description:
- a1_Inhibin B, produced by granulosa cells in the ovary, is a heterodimeric glycoprotein suppressing synthesis and secretion of the follicle stimulating hormone (FSH). The aim of the present study was to determine hormone profiles of inhibin B, FSH, luteinizing hormone (LH), and estradiol in girls during childhood and puberty and to evaluate whether inhibin B is a marker of follicle development. We examined the correlation between inhibin B and gonadotropins and estradiol during the first two years and across the pubertal development. Using a specific two-side enzyme-linked immunosorbent assay (ELISA), inhibin B levels were measured in the serum of 53 healthy girls divided into 8 groups according to age. In addition, serum FSH, LH, and estradiol were measured by chemiluminescent immunoassay in all serum samples. A rise in serum levels of inhibin B (55.2±7.3 ng/l, mean ± S.E.M.) and FSH (1.78±0.26 UI/l), concomitant with a moderate increment of serum LH (0.36±0.09 UI/l) and estradiol (45.8±12.2 pmol/l) concentrations was observed during the first three months of life and declined to prepubertal concentrations thereafter. A strong positive correlation between inhibin B and FSH (r = 0.48, p<0.05), LH (r = 0.68, p<0.001) and estradiol (r = 0.59, p<0.01) was demonstrated during the first 2 years of life. A rise in serum levels of inhibin B, FSH, LH, and estradiol was found throughout puberty. Inhibin B had a strong positive correlation with FSH (stage I of puberty: r = 0.64, p<0.05; stage II of puberty: r = 0.86, p<0.01), LH (I: r = 0.61, p<0.05; II: r = 0.67, p<0.05), and estradiol (II: r = 0.62, p<0.05) in early puberty. From pubertal stage II, inhibin B lost this relationship to gonadotropins and estradiol. Serum inhibin B and FSH levels increased significantly during pubertal development, with the highest peak found in stage III of puberty (133.5±14.3 ng/l), and decreased thereafter., a2_In conclusion, inhibin B is produced in a specific pattern in response to gonadotropin stimulation and plays an important role in the regulation of the hypothalamic-pituitary-gonadal axis during childhood and puberty in girls. Inhibin B is involved in regulatory functions in developing follicles and seems to be a sensitive marker of ovarian follicle development., M. Chada, R. Průša, J. Bronský, M. Pechová, L. Lisá., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
905. Inhibition of Beta-1 Receptor but not Vagotomy Can Abolish the L-NAME Evoked Bradycardia in Anesthetized Rat
- Creator:
- Vág, J., Hably, C., and Bartha, J.
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- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Nitric oxide, Vagotomy, Metoprolol, Heart rate, 14, and 612
- Language:
- English
- Description:
- We reported previously that the nitric oxide synthesis inhibitor Nv-nitro-L-arginine methyl ester (L-NAME) decreases cardiac output. Several studies have shown that inhibition of nitric oxide synthesis decreases the heart rate. In the present study, we investigated the effect of a single bolus administration of L-NAME on blood pressure and heart rate monitored for one hour in anesthetized rats and the influence of vagotomy and b1-receptor blocker metoprolol on the L-NAME induced bradycardia. After L-NAME treatment, the blood pressure rose immediately after the injection of the drug (peak response in the third minute: +24 %, p<0.001) and fell to the control level in the 20th minute. The heart rate decreased immediately after L-NAME administration, the lowest value being reached in the 10th minute (-14 %, p<0.001). However, bradycardia was sustained even after the blood pressure had returned to the control level. Bilateral vagotomy failed to influence the negative chronotropic effect of L-NAME, but bradycardia was completely abolished by metoprolol pretreatment. We concluded that the bradycardia evoked by L-NAME is mainly due to the withdrawal of sympathetic tone upon the heart rate. However, the cause of sustained bradycardia after normalization of blood pressure cannot be elucidated., J. Vág, C. Hably, J. Bartha., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
906. Inhibition of NO synthase activity in nervous tissue leads to decreased motor activity in the rat
- Creator:
- Lukáč Halčák, Oľga Pecháňová, Žigová, Z., Klemová, L., Novacký, M., and Iveta Bernátová
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- Subject:
- Fyziologie člověka a srovnávací fyziologie, oxid dusnatý, nitric oxide, L-NAME, nervous tissue, spontaneous behavior, habituation tasks, 14, and 612
- Language:
- English
- Description:
- The nitric oxide/cGMP system has been shown to play a crucial role in the mechanism of learning and memory. The aim of the present study was to investigate whether the inhibition of NO synthase in brain regions leads to alterations of spontaneous behavior in rats. Male Wistar rats were treated with NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) at the dose of 40 mg/kg/day. After 4 weeks of L-NAME treatment, NO synthase activity was significantly decreased by 75 % in the cerebellum, by 71 % in the cerebral cortex and by 72 % in the thoracic spinal cord. Decreased NO synthase activity in the nervous tissue was associated with decreased motor horizontal and vertical activities as well as by lowered frequency of sniffing, cleaning and defecation. It is concluded that the inhibition of NO synthase activity has a suppressive effect on spontaneous behavior of rats., L. Halčák, O. Pecháňová, Z. Žigová, L. Klemová, M. Novacký, I. Bernátová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
907. Inhibition of oxidative stress in brain during rat adjuvant arthritis by carnosine, trolox and novel trolox-carnosine
- Creator:
- Silvester Poništ, Slovák, L., Kuncírová, V., Fedorova, T., Logvinenko, A., Muzychuk, O., Danica Mihalová, and Bauerová, K.
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- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, artritida, mozek, oxidační stres, arthritis, brain, oxidative stress, trolox-carnosine, carnosine, 14, and 612
- Language:
- English
- Description:
- Carnosine (CARN) is an anti-glycating agent able to quench superoxide, and to neutralize 4-hydroxynonenal. Trolox-carnosine (CARN-T) was synthesized because of its resistance against degradation and to improve CARN antioxidant capacity. We evaluated the impact of trolox (TRO), CARN and its derivative CARN-T on oxidative stress (OS) in brain during rat adjuvant arthritis (AA). The experiments were done on healthy, control arthritic and arthritic animals with administration of CARN 150 mg/kg b.w., TRO 41 mg/kg b.w. and CARN-T 75 mg/kg b.w. in a daily dose during 28 days. Antioxidants did not affect the body weight on day 14, but on day 28 TRO enhanced the weight reduction. On day 14 and 28 CARN-T and TRO reduced arthritic score. IL-1beta, MCP-1 and MMP-9 were measured in plasma on day 14. MCP-1 was decreased by CARN-T and TRO. All antioxidants reduced IL-1beta and MMP-9 levels. Malondialdehyde, 4-hydroxynonenal and protein carbonyls were increased in brain. CARN, CARN-T and TRO prevented higher lipid and protein oxidation in brain. CARN and CARN-T caused no weight reduction like TRO that has an advantage in inflammatory arthritis. Moreover the antioxidants administered had a similar therapeutic effects on arthritic score, markers of inflammation in plasma and OS in brain., S. Poništ, L. Slovák, V. Kuncírová, T. Fedorova, A. Logvinenko, O. Muzychuk, D. Mihalová, K. Bauerová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
908. Inhibition of palmityl carnitine oxidation in rat liver mitochondria by tert-butyl hydroperoxide
- Creator:
- Zuzana Červinková, Hana Rauchová, Pavla Křiváková, and Zdeněk Drahota
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- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, mitochondrie, játra, physiology, mitochondrias, liver, palmityl carnitine oxidation, tert-butyl hydroperoxide, 14, and 612
- Language:
- English
- Description:
- Mitochondria as an energy generating cell device are very sensitive to oxidative damage. Our previous findings obtained in hepatocytes demonstrated that Complex I of the respiratory chain is more sensitive to oxidative damage than other respiratory chain complexes. We present additional data on isolated mitochondria showing that palmityl carnitine oxidation is strongly depressed at a low (200 μM) tert-butyl hydroperoxide (tBHP) concentration, while oxidation of the flavoprotein-dependent substrate - succinate is not affected and neither is ATP synthesis inhibited by tBHP. In the presence of tBHP, the respiratory control index for palmityl carnitine oxidation is strongly depressed, but when succinate is oxidized the respiratory control index remains unaffected. Our findings thus indicate that flavoprotein-dependent substrates could be an important nutritional factor for the regeneration process in the necrotic liver damaged by oxidative stress., Z. Červinková, H. Rauchová, P. Křiváková, Z. Drahota., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
909. Inhibition of soluble epoxide hydrolase does not improve the course of congestive heart failure and the development of renal dysfunction in rats with volume overload induced by aorto-caval fistula
- Creator:
- Luděk Červenka, Vojtěch Melenovský, Zuzana Husková, Sporková, A., Marcela Bürgelová, Petra Škaroupková, Hwang, S. H., Hammock, B. D., Imig, J. D., and Sadowski, J.
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, congestive heart failure, aorto-caval fistula, renin-angiotensin system, epoxyeicosatrienoic acids, soluble epoxide hydrolase, 14, and 612
- Language:
- English
- Description:
- The detailed mechanisms determining the course of congestive heart failure (CHF) and associated renal dysfunction remain unclear. In a volume overload model of CHF induced by creation of aorto- caval fistula (ACF) in Hannover Sprague -Dawley (HanSD) rats we explored the putative pathogenetic contribution of epoxyeicosatrienoic acids (EETs), active products of CYP -450 dependent epoxygenase pathway of arachidonic acid metabolism, and compared it with the role of the renin-angiotensin system (RAS). Chronic treatment with cis -4-[4-(3-adamantan -1-yl- ureido) cyclohexyloxy]benzoic acid (c-AUCB, 3 mg /l in drinking water), an inhibitor of soluble epoxide hydrolase (sEH) which normally degrades EETs, increased intrarenal and m yocardial EETs to levels observed in sham -operated HanSD rats, but did not improve the survival or renal function impairment. In contrast, chronic angiotensin -converting enzyme inhibition (ACEi, trandolapril, 6 mg /l in drinking water) increased renal blood flow, fractional sodium excretion and markedly improved survival, without affecting left ventricular structure and performance. Hence, renal dysfunction rather than cardiac remodeling determines long-term mortality in advanced stage of CHF due to volume o verload. Strong protective actions of ACEi were associated with suppression of the vasoconstrictor/sodium retaining axis and activation of vasodilatory/natriuretic axis of the renin -angiotensin system in the circulating blood and kidney tissue., L. Červenka, V. Melenovský, Z. Husková, A. Sporková, M. Bürgelová, P. Škaroupková, S. H. Hwang, B. D. Hammock, J. D. Imig, J. Sadowski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
910. Inhibition of the acquisition of conditioned place aversion by dopaminergic lesions of the central nucleus of the amygdala in morphine-treated rats
- Creator:
- Xu, W., Li, Y. H., Tan, B. P., Luo, X. J., Xiao, L., Zheng, X. G., Yang, X. Y., and Sui, N.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, conditioned place aversion, central nucleus of amygdala, dopamine, 6-OHDA, 14, and 612
- Language:
- English
- Description:
- The negative affective state of opiate abstinence plays an important role in craving and relapse to compulsive drug use. The dopamine system participates in the reward effects of opiate use and the aversive effect of opiate abstinence. The amygdala is an essential neural substrate for associative learning of emotion. To establish a model of conditioned place aversion (CPA) in morphine-treated rats, we used different visual and tactual cues as conditioned stimuli (CS) within a conditioning apparatus. An injection of naloxone served as the unconditioned stimulus (US). The 6-hydroxydopamine (6-OHDA) lesion technique was used to investigate the effects of the dopaminergic system of the central nucleus of the amygdala (CeA) on naloxone-induced CPA. Rats were rendered physically dependent via administration of increasing doses of morphine delivered via intraperitoneal injection. Doses increased by 20 % each day for 14 days, starting from an initial dose of 6 mg/kg. All rats also received a low dose of naloxone (0.1 mg/kg) by injection 4 hours after morphine treatment on days 11 and 13 to induce CPA in a biased twocompartment conditioned place apparatus. Morphine-dependent rats with sham lesions were found to develop significant CPA after naloxone treatment. Bilateral 6-OHDA lesions of the CeA impaired the acquisition of CPA but had no effect on locomotor activity. These results suggest that the dopaminergic system of the CeA plays an important role in the negative affective state of opiate abstinence., W. Xu ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public