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Recently growth hormone therapy has been used as an age delaying drug in middle aged men and women as well as in the elderly. Positive effects have been shown in regards to body mass and body composition changes, fat metabolism, bone mineral density and muscle strength. Exercise is a potent physiological stimulus for growth hormone secretion and both aerobic and resistance exercise results in significant, acute serum increases in GH concentration. It is unclear however whether a combination of exercise and hGH therapy further increases physical performance in adults and increases changes in body composition and biochemical variables related to health. For this purpose a group of 15 middle aged men (45,7±5,8 years, 93,2±16,3kg and 183,3±4cm), slightly overweight were randomly divided into an experimental and control groups. Both groups exercised for 3 month, performing 2 aerobic sessions per week and 2 resistance workouts, increasing training loads every two weeks. The experimental group received additionally hGH subcutaneous injections beginning with 0,2 IU daily for the first month and then increasing it to 0,4 and 0,6 IU in successive month. VO2max was evaluated during a progressive ergocycle test to volitional exhaustion, while anaerobic power and capacity were measured during the 30s Wingate test. Additionally body mass and body composition were evaluated as well as the lipoprotein profile and the concentration of chosen anabolic hormones. The results indicate a significant rise in resting concentrations of GH and IGF-1 after the replacement therapy but no additional benefits in regards to aerobic fitness and fat metabolism in comparison to exercise only. A more profound effect was observed in case of anaerobic performance, thus it was concluded that even small doses of hGH stimulated additional protein synthesis following resistance exercise what allowed for significant increases in FFM, anaerobic power (W/kg) and capacity (J/kg) as evaluated obtained during the Wingate test. It was concluded that for a more significant effect of hGH therapy in regards to physical performance greater doses of this hormone have to be used, along with an intensive exercise program.
Content available remote Neural modelling of growth hormone therapy for the prediction of therapy results
In this paper, we presented the problem of predicting response to recombinant human growth hormone (GH) treatment in GH-deficient children. Such a prediction can be done by techniques of mathematical modelling and is important because the therapy consists of daily injections and is expensive; thus, it should be administered only to those patients who will, with high probability, benefit from it. Until now, the leading methodological approach to this problem was multiple regression analysis. Several authors demonstrated that it is possible to derive useful models by this method; however, it has some obvious limitations that can be avoided with the use of the proposed neural network approach.
Commensal bacteria and their genes associated with host are known as microbiome. In recent years, microbial influence on host endocrine system has been under detailed investigation. The role of microbiome in the pathogenesis of insulin resistance and obesity, the function of hypothalamic-pituitary-adrenal axis and secretion of hormones regulating appetite is well described in world literature. In this article we discuss poorly reviewed issues: the microbiome role in modulation of non-peptide (sex and thyroid) and peptide (growth hormone and parathyroid hormone) functions. Understanding complex bidirectional relations between host endocrine system and bacteria is of fundamental importance to understanding microbial impact on host reproduction, risk of endocrine-related cancers, pathogenesis of non-thyroidal illness syndrome, growth failure in children and hormonal changes during chronic kidney disease. This article also highlights effects of dietary compounds on microbiome composition and bacterial enzymes activity, and thus host hormonal status.
The aim of this study was to identify SNPs in leptin (LEP), leptin receptor (LEPR) and growth hormone (GH) genes in order to analyze genetic diversity of Slovak Spotted cattle. The total numbers of blood samples were taken from 353 Slovak Spotted cows originating from four farms. Genomic DNA was isolated by phenol-chloroform extraction method and analyzed by PCR-RFLP method. After digestion with restriction, enzymes were detected in whole population of cow's alleles with frequency: LEP/Sau3AI A 0.84 and B 0.16 (±0.0152); LEPR/BseGI C 0.95 and T 0.05 (±0.0089) and GH/AluI L 0.70 and V 0.30 (±0.0188). Based on the observed vs. expected genotypes frequencies populations across loci were in Hardy-Weinberg equilibrium (P\>0.05). Predominant for SNP LEP/Sau3AI was AA genotype (0.70), for SNP LEPR/T945M CC genotype (0.91), and LL genotype (0.48) was most frequent for SNP GH/AluI. The observed heterozygosity of SNPs across populations was also transferred to the low or median polymorphic information content 0.24 (He 0.28), 0.08 (He 0.09) and 0.33 (He 0.47) for LEP, LEPR and GH genes, respectively. Within genetic variability estimating negative values of fixation indexes FIS (-0.09-0.05) and FIT (-0.07-0.03) indicating heterozygote excess were observed. The value of FST indexes (0.018-0.023) shows very low levels of genetic differentiation in allele frequencies of loci among evaluated subpopulations. The low values of genetic distances (0.0018-0.0159) indicated high genetic relatedness among animals in subpopulations caused probably by common ancestry used in breeding program at farms.
Adequate levels of strength and flexibility are important for the promotion and maintenance of health and functional autonomy as well as safe and effective sports participation. The aim of the present study was to analyze the effects of 8 weeks of strength training with or without inter-set static stretching on strength, flexibility and hormonal adaptations of trained men. Sixteen trained men were randomly divided into 2 groups: the static stretching group (SSG) and passive interval group (PIG). All participants performed 24 training sessions 3 times a week. The test and retest of 8RM, strength, flexibility, cortisol and growth hormone concentration in pre and post test conditions were also evaluated. To compare the differences between and within groups in pre- and post-training tests, ANOVA with repeated measures was performed (SSGpre x SSGpost; PIGpre x PIGpost; SSGpost x PIGpost). An alpha level of p<0.05 was considered statistically significant for all comparisons. Both groups showed significant increases in strength (SSGpre vs. SSGpost; PIGpre vs. PIGpost) in the same exercises for leg extension (LE) and Low Row (LR). Specifically, in the SSG group, the parameters for LE were (p = 0.0015 and ES = 2.28 - Large), and the parameters for LR were (p = 0.002 and ES = 1.95 - Large). Moreover, in the PIG group, the parameters for LE were (p = 0.009 and ES = 1.95 - Large), and the parameters for LR were (p = 0.0001 and ES = 2.88 - Large). No differences were found between the groups (SSGpost vs. PIGpost). Both groups showed significant increases in flexibility but in different joints (SSGpre vs. SSGpost; PIGpre vs. PIGpost). In the SSG group, only three joints showed significant increases in flexibility: shoulder extension (p = 0.004 and ES = 1.76 - Large), torso flexion (p = 0.002 and ES = 2.36 - Large), and hip flexion (p = 0.001 and ES = 1.79 - Large). In the PIG group, only three joints showed increases in flexibility: horizontal shoulder abduction (p = 0.003 and ES = 2.07 - Large), hip flexion (p = 0.001 and ES = 2.39 - Large), and hip extension (p = 0.02 and ES = 1.79 - Large). In-between group analyses (SSGpost x PIGpost) revealed differences in two joints: shoulder extension (p = 0.001) and horizontal shoulder abduction (p = 0.001). Hormonal profiles showed no significant differences in cortisol secretion or growth hormone concentration. In conclusion, both studied strength protocols (with and without inter-set static stretching) resulted in flexibility and strength gains without an effect on the anabolic and catabolic hormonal profile.
The aim of this study was to evaluate the effects of steroidal saponin supplementation on blood concentration of T, GH and IGF-1. The research involved 14 men between the age of 45 and 60 years. The duration of the experiment was 12 weeks. There were two series of laboratory tests. Independent tests were conducted at the beginning and after 12 weeks of the intervention. A two-way repeated measures ANOVA revealed a statistically significant effect of the intervention on the following variables: T-Ch (η2 = 0.542), HDL-Ch (η2 = 0.522), LDL-Ch (η2 = 0.587), T (η2 = 0.603), IGF-1 (η2 = 0.512) and GH (η2 = 0.621). Thus, FFM significantly increased while TBF and BM decreased in comparison to pre-intervention levels. The analyzed results indicate that treatment or supplementation of individual hormone deficiencies can be a successful form of counteracting the aging process. Nevertheless, the effects of TT supplementation on the concentration of T as well as GH and IGF-1, requires further studies, especially in middle-aged and older subjects, along with different exercise programs. The analyzed results indicate that treatment or supplementation of individual hormone deficiencies can be a major form of counteracting the aging process.
The goal of this study was the assessment of the influence on both insulin and growth hormone levels in lambs blood of blood meal and Wroclaw product - dry brown livex (modified by whey). Experiments were carried out on 30 young Polish "wielkopolska" lowland - sheep - wool type, aged 3-4 months. Livex and blood meal constituted 2% of forage. Blood samples for radioimmunologic examinations (GH and insulin level determination) were taken 1 hour before feeding, directly before feeding and 1.0, 1.5, 2.0, 3.0, 5.0, 6.0 and 8.0 hours afterwards. During the experiment higher levels of insulin and GH were observed in animals fed with livex and forage mixture than in animals fed with blood meal and forage mixture. Livex caused a bigger body mass increase (mean increase 27.3%) in comparison with animals fed with control forage. Although neither livex nor blood meal are hormone preparations, changes in insulin and growth hormone levels were observed.
Objectives Gonadoliberin (GnRH) analogs may be expected to indirectly modify growth hormone (GH) total concentration and its 24-h secretion profile. As a consequence, changes in the levels of GH may modify the mechanism of sexdependent cytochromes P450 (CYP450) synthesis, including the expression of transcriptional factors. The aim of the study has been to evaluate the effect of long-term administration of a low dose of GnRH analogs on hepatic expression of CYP2C and CYP3A isoforms, and the transcription factors: pregnane X receptor (PXR), hepatocyte nuclear factor 4α (HNF4α), HNF6 and signal transducers and activators of transcription 5b (STAT5b). Material and Methods The study was carried out on adult female Sprague-Dawley rats during a 3-month treatment with dalarelin (GnRH agonist) and cetrorelix (GnRH antagonist), at a daily intraperitoneal injection (i.p.) dose of 6 μg/kg body weight/day, and 1, 2, and 4 weeks after treatment discontinuation. The concentrations of ovarian hormones and GH in the blood serum were determined by radioimmunoassay and enzyme-linked immunosorbent assay (ELISA) method, respectively. Then, the expression of hepatic CYP450s (reverse transcription polymerase chain reaction – RT-PCR, Western blot and immunohistochemistry) and transcription factors (RT-PCR) was evaluated. Results We have found that cetrorelix induces changes in the circadian pattern of GH secretion and enhances GH blood concentrations. These changes may cause increased expression of both, female-specific CYP450s (especially CYP3A9), and HNF4α/HNF6 transcription factors. Decrease in GH blood concentrations, resulting from the effect of dalarelin, may promote inhibition of female-specific CYP2C12 and CYP3A9 isoforms as well as STAT5b transcription factor. Slight changes in sex-independent CYP3A1 protein expression caused by GnRH analogs were also observed. Conclusions In adult female rats, HNF4α/HNF6 and STAT5b seem to be crucial for the regulation of GnRH antagonist/GH- and GnRH agonist/GH-dependent pattern of CYP450 expression, respectively.
Arginine is a semi-essential amino acid taking part in the processes involved in the biosynthesis of proteins, the regulation of endothelium activity and the detoxification of an organism. The importance of the proper use of arginine increases in such physiological conditions as a disease, an injury or a substantial overload of an organism. The potential ergogenic influence of arginine supply, through the stimulation of nitric oxide synthesis, human growth hormone and creatine, makes arginine very popular among sportsmen. Many clinical tests present the relationship between arginine supply and the functional capacity improvement and the beneficial regulation of endocrinologic parameters. Such results are explicit while testing convalescents or those suffering from cardiovascular diseases. However, the results of highly-trained and healthy sportsmen are ambiguous. It might be very often observed that there is no connection between arginine and power, strength and muscle mass, the maximum oxygen consumption, the human growth hormone and nitric oxide concentration. Taking it into consideration, the necessity of further research on the functionality of increasing arginine supply among various sportsmen, is firmly supported. Nevertheless, such research needs to be restricted by appropriate procedures, considering cross-over study with double- blind test.
In this study, favorable carbon-nitrogen ratio for high yields of gibberellic acid (GA₃) production from Pseudomonas sp. was investigated. First of all, optimum carbon (glucose, maltose, sucrose, fructose, lactose) and nitrogen (KNO₃, NH₄C1, NaNO₃, urea, glycine) sources among the others were chosen. The highest yield of GA₃ productivity was found in growth medium supplemented with fructose (168.5 mg/L). NaNO₃ was found as a suitable nitrogen source (141 mg/L). Then, in order to determine the optimum carbon-nitrogen ratio, different concentrations of carbon (from 50 mM to 150 mM) and nitrogen (from 17 mM to 47 mM) sources were added in culture media. As a result, optimum carbon-nitrogen ratio for GA₃ production from Pseudomonas sp. was found to be 100:17 mM.
The objective of this study was to investigate the effect of two single nucleotide polymorphisms iIn growth hormone (GH) gene on performance traits in pigs. The animals (n= 320) belonged to four groups of commercial crosses being the progeny of crossbred Polish Landrace × Polish Large White sows and Polish Landrace, Polish Large White, Duroc or Pietrain boars. Genotypes of growth hormone gene (GH) were established with PCR-RFLP technique using MspI and HaeII endonucleases.The GH/MspI and GH/HaeII genotypes were found significantly related to the weight of ham, Wright of ham meat and ham content of carcass. Moreover, nearly significant differences between GH/MIPS genotypes were found for mean fat thickness (from five measurements), fat thickness at lower back (point K2) and over the loin, and for loin eye height. The results presented allow to assume that near the analysed mutation the QTLs for performance traits in pigs are located.
Celem badań było określenie zależności między cechami użytkowymi świń a polimorfizmem genu hormonu wzrostu (GH). Materiał badawczy stanowiły zwierzęta pochodzące z krzyżowania knurów czystych ras (pbz, wbp, Duroc, Pietrain) z lochami mieszańcowymi (wbp × pbz). Analizą objęto 18 cech tempa wzrostu i jakości tuszy 320 zwierząt. Istotne zależności między analizowanymi genotypami GH/MspI i GH/HaeII odnotowano dla masy szynki, masy mięsa szynki oraz udziału masy szynki w tuszy (%). Ponadto stwierdzono bliskie istotności zależności między genotypem GH/MspI a średnią grubością słoniny z pięciu pomiarów, grubością słoniny mierzoną na krzyżu w punkcie K2, grubością słoniny okrywającej polędwicę oraz wysokością oka polędwicy. Prezentowane wyniki wraz z wcześniejszymi doniesieniami potwierdzają tezę, że w rejonie chromosomu 12 obejmującym locus GH znajdują się QTLs, które istotnie wpływają na poziom cech użytkowych świń.
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