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Comparative Study 2004; 25(1-2): 83-86 PubMed PMID: 15159689 Citation  Keywords:  Animals, Antigens, CD13:metabolism, Blood Glucose:analysis, Cathepsin D:metabolism, Cathepsin L, Cathepsins:metabolism, Cysteine Endopeptidases, Down-Regulation, Female, Insulin:physiology, Kidney:enzymology, Leucyl Aminopeptidase:metabolism, Liver:enzymo.   

OBJECTIVES: Changes in the activity of alanine aminopeptidase, leucine aminopeptidase and cathepsins D and L in the liver and kidney of male and female of mice, injected with 0.4 IU/kg b.w. insulin for 4 and 8 days.

METHODS: The homogenates of the liver and kidney were taken for examination. The activity of alanine aminopeptidase, leucine aminopeptidase and cathepsins D and L has been determined according to [1] method.

RESULTS: The activity of alanine aminopeptidase, leucine aminopeptidase, cathepsins D and L in the liver and kidney of male and female of mice decreased in effect of insulin injections for 4 and 8 days.

CONCLUSION: The changes of enzyme activities showed a stimulating effect of the insulin injection on the labilization of lysosomal membranes. The range of the reaction remained in a relationship with the kind of the organ, the type of enzyme, time over which insulin introduced operates in the organism, and with the sex....

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Journal Article 2003; 24(5): 325-328 PubMed PMID: 14647005 Citation  Keywords:  Aldosterone:urine, Blood Pressure:genetics, Genetic Markers, Humans, Hypertension, Renal:genetics, Insulin:genetics, Middle Aged, Minisatellite Repeats, Phenotype, Pilot Projects, Polymorphism, Restriction Fragment Length, Potassium:urine, Quantitative Tr.   

BACKGROUND: Blood pressure regulation is a complex process influenced by numerous environmental and genetic factors. Consequently, there's no cookie-cutter approach for the elucidation of of the genetic mechanism involved. One of the goals of molecular geneticists in the field of hypertension is to unravel the genetic architecture of blood pressure regulation.

METHODS: With the aim of identifying quantitative trait loci participating in the control of blood pressure, we carried out a pilot study on a sample population of middle-aged, U.S. Caucasians (44 subjects). The design of the study was to search for associations between clinical variables of blood pressure regulation pertaining to the renin-angiotensin-aldosterone system (systolic and diastolic blood pressures, urinary excretion of sodium, potassium and aldosterone, plasma renin activity) and a genetic marker at a candidate gene locus - the human insulin gene (INS) RESULTS: We observed significant associations between a variable number of tandem repeats (VNTR) marker (visualized as a biallelic, class I/class III marker system) localized at the 5' end of the human INS gene, and plasma renin activity and urinary sodium, potassium and aldosterone.

CONCLUSION: Our results indicate that between 6 and 10 QTLs with comparable effects could be involved in blood pressure regulation via the rennin angiotensin system....

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Journal Article 2002; 23(5-6): 437-439 PubMed PMID: 12500166 Citation  Keywords:  Animals, Diabetes Mellitus, Experimental:chemically induced, Disease Models, Animal, Insulin:pharmacology, Insulin-Like Growth Factor I:analysis, Male, Rats, Rats, Sprague-Dawley, Sulfonylurea Compounds:pharmacology,.   

OBJECTIVE: Diabetes Mellitus is associated with decreased insulin-like growth factor-I (IGF-I) levels and also, poor growth in diabetes is related with low circulating levels of IGF-I. Insulin acts via an increase of IGF-I synthesis on growth. We studied the effects of insulin and sulphonylureas on serum IGF-I levels and aimed to evaluate the restoration of IGF-I in different therapeutic strategies.

DESIGN AND SETTING: Thirty male rats were used in the study and diabetes was induced by a single intraperitoneal injection of streptozotocin (35 mg/kg body weight). After confirmation of hyperglycemia, rats were divided into three groups. The first group was treated with insulin, and second group with glimepiride, third group was not treated (control group). IGF-I levels were measured at basal, after streptozotocin and at the end of the treatment period.

RESULTS: Serum IGF-I levels were found to decrease from 577.2 ng/ml to 253.0 ng/ml after streptozotocin (p<0.005). After 1 month, IGF-1 levels were found 524.0 ng/ml in insulin group, 449.3 ng/ml in sulphonylurea group, and 313.1 ng/ml in control group. The increase in IGF-I was statistically significant in insulin group (p<0.005), and in sulphonylurea group (p<0.05), but it was not significant in control group (p>0.05).

CONCLUSIONS: Serum IGF-I levels decrease in diabetes and insulin treatment restores IGF-I depletion significantly. And although less effective, treatment with glimepiride restores IGF-I levels significantly....

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Journal Article 2001; 22(4): 255-262 PubMed PMID: 11524633 Citation  Keywords:  Animals, Circadian Rhythm:drug effects, Drug Administration Schedule, Growth Hormone:blood, Insulin-Like Growth Factor I:metabolism, Male, Melatonin:administration & dosage, Oscillometry, Osmolar Concentration, Pineal Gland:physiology, Rats, Rats, Wistar,.   

BACKGROUND: A relationship between circadian GH-IGF-I axis activity and pineal gland function in rats is not sufficiently elucidated, particularly in the aspect of melatonin (MEL) participation with relation to a possible mechanism of these dependencies.

OBJECTIVE: Influence of pinealectomy and long-term MEL administration on circadian GH-IGF-I axis function in male rats was evaluated. An attempt was also made to determine whether the effect of exogenous MEL is dependent on the pineal gland presence.

METHODS: Studies were performed in 192 sexually mature male Wistar rats, which were subjected to pinealectomy or sham operation. In half of the animals from each group MEL (Sigma, USA) in dose of 50 microg/ 100g b.m. was administrated intraperitoneally (daily between 5 and 6 pm during a 4-week period). Blood for RIA assays of MEL, GH and IGF-I concentrations was collected every 3 hours during a day-beginning at 8 am (rats killed by decapitation).

RESULTS: Significant influence of pinealectomy and exogenous MEL on a daily profile of endogenous MEL in rats was confirmed. Distinct, dependent on the time of the day anomalies in circadian oscillations of GH and IGF-I showing positive correlation with changes in endogenous MEL concentrations were also shown. GH rhythm was suppressed in a group of rats with removed pineal gland; after pinealectomy distinct decrease and after MEL use - distinct increase of GH and IGF-I concentrations during the day were observed. It had influenced mean daily concentrations and values of amplitude of circadian GH and IGF-I oscillations in all studied groups of animals. In rats with preserved pineal gland the effect of exogenous MEL action was more intensified.

CONCLUSIONS: Pineal gland can influence circadian function of GH-IGF-I axis, and in mechanism of this dependence, changes in endogenous MEL concentrations seem to play an important role. Administration of MEL in rats after pinealectomy only partly prevents changes of GH-IGF-I axis function caused by gland removal, which can indicate participation of other pineal gland substances in generating disturbances. Influence of exogenous MEL on GH-IGF-I axis function during the day is dependent on the presence of pineal gland, which can be connected with indirect and/or direct influence of administrated hormone on this gland....

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Journal Article 2001; 22(4): 238-242 PubMed PMID: 11524629 Citation  Keywords:  Animals, Blood Glucose:analysis, Cholesterol:blood, Diabetes Mellitus, Experimental:metabolism, Hydrolases:metabolism, Insulin:blood, Kidney:enzymology, Liver:enzymology, Lysosomes:enzymology, Male, Rabbits,.   

OBJECTIVES: The study was carried out on fifty male rabbits of the New Zealand White breed. Diabetes was caused by a single, intravenous alloxan injection. Rabbits which had glycaemia 7th day after the alloxan administration higher than 11 millimol/litre were selected for the studies. They were divided into 5 groups: I - control (without diabetes); II - 3-week diabetes; III - 6-week diabetes; IV - 3-month diabetes; V - 6-month diabetes.

METHODS: In control and experimental rabbits the activity of beta-glucuronidase, N-acetyl-beta-glucosaminidase, lysosomal acid phosphatase, leucine aminopeptidase, cathepsin D, and lysosomal arylesterase was determined in lysosomal fractions of the liver and kidney.

RESULTS: Alloxan caused lowering of the activity of all the investigated enzymes in the kidney and liver except lysosomal arylesterase.

CONCLUSION: Alloxan injection caused a significant increase in the activity of all the investigated enzymes. The advisable lysosomal enzymes may be useful for the monitoring of the course and effectiveness of diabetes therapy....

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Journal Article 2018; 39(3): 179-188 PubMed PMID: 30431745 Citation  Keywords:  Carcinogenesis, Head and Neck Neoplasms:metabolism, Human Growth Hormone:metabolism, Humans, Insulin-Like Growth Factor I:metabolism, Intercellular Signaling Peptides and Proteins:metabolism, Neoplasms:metabolism, Prolactin:metabolism, Receptors, Somatotr.   

: The interaction between pituitary hormones, GH - PRL, and Growth Factors, GF, plays a fundamental role in the physiological and neoplastic mechanisms of growth, the latter using these factors to a much greater extent compared to the former, with a direct dose-dependent effect on the speed of local or metastatic expansion. In hormone-dependent tumours, the respective male and female sex hormones interact with GH - PRL - GF to sustain the expansion of the tumour. We carried out a review of the literature on the relationship between the expression of GH and GHR in tumour tissues compared to healthy tissues, and on the correlation between this expression and tumour aggressiveness. An over-expression of GH and GHR in tumours was a constant finding. In more than a thousand cases published in various clinical, observational, retrospective studies investigating cervico-facial tumours, lymphoproliferative diseases, breast cancer, prostate cancer, non-small-cell lung cancer, neuroblastomas, oesophageal cancer, glioblastomas, and sarcomas, we constantly found an improvement in objective response, quality of life and survival, compared to conventional oncological protocols, by inhibiting GH and correlated GF using somatostatin....

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Journal Article 2018; 39(3): 172-178 PubMed PMID: 30431742 Citation  Keywords:  Adipose Tissue:metabolism, Anorexia Nervosa:metabolism, Appetite, Bulimia Nervosa:metabolism, Ghrelin:metabolism, Glucuronidase:metabolism, Gonads:metabolism, Human Growth Hormone:metabolism, Humans, Hypothalamo-Hypophyseal System:metabolism, Insulin-Like.   

: Endocrine dysfunctions in eating disorders (anorexia nervosa, bulimia nervosa) result from disturbed regulation of hypothalamo-pituitary-gonadal, hypothalamo-pituitary-adrenal, hypothalamo-pituitary-thyroid and hypothalamo-pituitary-GH-IGF1 axes as well as of altered peripheral endocrine metabolism. Some peptides of hypothalamic origin, as well as those secreted by the adipose tissue and gastrointestinal tract including pancreatic hormones, are involved in the control of appetite and satiety. These peptides play also an important role in the mechanism of hormonal secretion. Altered activity of these biologically active substances may lead to the disturbances in the regulation of energy and hormonal homeostasis....

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Journal Article 2018; 39(4): 342-348 PubMed PMID: 30531700 Citation  Keywords:  Adult, Cross-Sectional Studies, Human Growth Hormone:blood, Humans, Hydrocortisone:blood, Insulin-Like Growth Factor I:metabolism, Male, Resistance Training, Testosterone:blood, Time Factors, Weight Lifting,.   

OBJECTIVE: Research indicates that among the many elements of resistance exercise protocols, training volume and total training load are the key factors for post-exercise increase in the secretion of testosterone (T), growth hormone (GH), insulin-like growth factor (IGF-1) and cortisol (C). The aim of this study was to determine the effects of resistance exercises with variable volume and constant intensity and movement tempo on post-exercise concentrations of selected anabolic and catabolic hormones. MATERIALS AND METHODS: 28 experienced powerlifters (27.8 ± 2.9 years, with 6.64 ± 1.29 years of training experience, average body mass of 85.3 ± 3.3 kg and body height of 165.8 ± 10.3 cm) who compete at the national and international level performed three repetitions of barbell squats with a constant external load of 90% 1RM and variable volume (3, 6 and 12 sets of squats) in three stages (pre-exercise, immediately post exercise, and 1h after exercise) over three consecutive weeks. Venous blood samples (10ml) were collected from the antecubital vein, to determine pre- and post-exercise values of the following variables T, GH, IGF-1, C, at rest, immediately after the cessation of the last set of squats, and after 60 minutes of recovery. RESULTS: The T test showed that performing 6 and 12 sets resulted in increases of post exercise GH (p<0.01). Performing 6 sets of squats resulted in post exercise decrease (p<0.01) in IGF-1 and C. Performing 3 sets of squats resulted in immediate post exercise decrease of IGF-1 (p<0.01), which was not maintained 1h after exercise. There were no other significant differences in analysed variables, with the training volume of three sets of three repetitions, confirming previous data suggesting that low volume is the limiting factor in increased post-exercise secretion. CONCLUSION: This study demonstrated that in terms of endocrine response, the optimal volume of high intensity strength exercise is six sets. Therefore, intentionally high volume (12 sets) or low volume (3 sets) are not an effective stimuli for endocrine responses of trained individuals. The 6 sets of squats seems to drive hormonal responses of GH, C and IGF-1, which may play a significant role in stimulating muscle growth and tissue regeneration....

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