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Comparative Study 2006; 27(3): 369-372 PubMed PMID: 16816828 Citation  Keywords:  Adaptation, Physiological:drug effects, Analysis of Variance, Animals, Cholesterol:metabolism, Cold Temperature, Female, Hot Temperature, Kidney:metabolism, Lipid Metabolism:drug effects, Lipids:blood, Liver:metabolism, Male, Mice, Muscarinic Antagonists:.   

OBJECTIVES: The effect of scopolamine administration at dose 0,5 g/kg b.w. and high (+40 degrees C) and low (+4 degrees C) temperature on the level of triacyloglycerides, total lipids and cholesterol in the mouse liver, kidney and muscle of males and females.

METHODS: The homogenates of the liver, kidney and muscle were taken for examination. The concentrations of triacyloglycerides, total lipids and cholesterol was estimated according to the Bio-La-Tests (Poland).

RESULTS: The concentration of triacyloglycerides and total lipids in the liver, kidney and muscle increased of males and females after scopolamine injections and after exposure to high and low temperatures.

CONCLUSION: Scopolamine may effect an increase in the rate of the lipid metabolism....

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Journal Article 2006; 27(1-2): 225-230 PubMed PMID: 16648797 Citation  Keywords:  Absorptiometry, Photon, Adolescent, Adult, Aged, Aldehydes:blood, Body Composition:physiology, Body Mass Index, Bone Density:physiology, Female, Glucose Intolerance:physiopathology, Glucose Tolerance Test, Human Growth Hormone:blood, Humans, Lipid Peroxid.   

OBJECTIVES: Growth hormone (GH) deficiency in adults is associated with a higher risk of atherosclerosis and cardiovascular disease. It has recently been suggested that enhanced oxidative stress may be implicated in vascular (and probably other) disturbances, occurring in GH-deficient subjects. The aim of the study was to evaluate serum levels of lipid peroxidation (LPO) products in adult patients with severe GH deficiency during insulin tolerance test (ITT), and to estimate the relationships between LPO and GH, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and other parameters of metabolic processes.

MATERIAL AND METHODS: Twelve adult patients with severe GH deficiency hospitalized in our department and 12 healthy volunteers, matched for sex, age and body mass index (BMI), were enrolled in the study. Peripheral blood was collected during ITT. The concentrations of malondialdehyde + 4-hydroxyalkenals (MDA+4-HDA), as an index of LPO, were measured in blood serum.

RESULTS: Serum LPO level was approximately twice as high in GH-deficient patients as in the controls at each time point of ITT. A positive correlation was found between bone mineral density in the lumbar spine and GH concentration in GH-deficient patients. A positive correlation was found between LPO and BMI in the controls, but no such correlation was observed in GH-deficient patients.

CONCLUSION: The increased LPO in GH-deficient patients may indicate enhanced oxidative stress within the vascular compartment and, possibly, in other tissues, which may contribute to the proatherogenic state and corresponding organ disturbances in GH-deficient patients, independently from conventional risk factors....

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Comparative Study 2005; 26(6): 795-798 PubMed PMID: 16380688 Citation  Keywords:  Animals, Antioxidants:metabolism, Brain:enzymology, Glutathione:metabolism, Hyperthyroidism:metabolism, Lipid Peroxidation:physiology, Liver:enzymology, Male, Malondialdehyde:metabolism, Myocardium:enzymology, Pineal Gland:physiology, Rats, Rats, Sprague-.   

OBJECTIVE: Thyroid hormones regulate energy metabolism and act on the mitochondria, which is an important source of free radicals in the cell. Reactive oxygen types play a significant role in physiological mechanisms, but in excessive amounts they can cause oxidative damage in molecules. The aim of the present study was to determine levels of lipid peroxidation caused by induced hyperthyroidism in cerebral, hepatic and cardiac tissues of pinealectomized rats.

METHODS: Experimental animals used in the study were allocated to three groups as general control group, hyperthyroidism-sham pinealectomy group and hyperthyroidism-pinealectomy group. GSH and MDA levels in cerebral, hepatic and cardiac tissues were evaluated at the end of the 3-week study period.

RESULTS: It was found that MDA levels in cerebral, hepatic and cardiac tissues were the highest in hyperthyroidism and pinealectomy group and that these values were higher in hyperthyroidism-sham pinealectomy group than in the control group (p<0.001). It was seen that tissue GSH levels significantly increased in hyperthyroidism-sham pinealectomy group (p<0.001) and that the increase in hyperthyroidism and pinealectomy group was higher than the increase in the control group only (p<0.001).

CONCLUSION: Results of our study show that MDA and GSH levels in cerebral, hepatic and cardiac tissues increased due to hyperthyroidism and that the increase in MDA levels became more evident and GSH levels were significantly suppressed after pinealectomy....

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Comparative Study 2005; 26(6): 806-810 PubMed PMID: 16380687 Citation  Keywords:  Animals, Glutathione:metabolism, Hyperthyroidism:chemically induced, Kidney:metabolism, Lipid Peroxidation, Male, Malondialdehyde:metabolism, Melatonin:metabolism, Oxidative Stress:physiology, Rats, Rats, Sprague-Dawley, Testis:metabolism, Thyroxine,.   

OBJECTIVE: The present study aimed at determining how 3-week intraperitoneal melatonin administration affected oxidative stress caused by experimental hyperthyroidism.

MATERIALS AND METHODS: The study was conducted on 30 male rats of Sprague-Dawley species. The experimental animals were divided to 3 groups (control, hyperthyroidism and hyperthyroidism+melatonin). The supplementation was continued for 3 weeks after which the animals were sacrificed and tissue malondyaldehyde (MDA) and glutathione (GSH) levels were determined.

RESULTS: MDA levels in kidney and testis tissues in hyperthyroidism group were higher than those in control and hyperthyroidism+melatonin administered groups (p<0.001) and levels in hyperthyroidism+melatonin administered group were higher than those in the control group (p<0.001). The highest GSH levels were obtained in hyperthyroidism+melatonin-administered group (p<0.001) and GSH levels in hyperthyroidism group were higher than those in the control group (p<0.001).

CONCLUSION: Results of the study demonstrate that hyperthyroidism induced by 3-week L-thyroxine administration increased oxidative stress in kidney and testis tissues and that although melatonin administration inhibited this stress to a certain extent, it could not bring the stress down to the level in controls....

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Comparative Study 2005; 26(6): 704-708 PubMed PMID: 16380675 Citation  Keywords:  Analysis of Variance, Animals, Antioxidants:pharmacology, Antithyroid Agents:pharmacology, Brain:metabolism, Hydrocarbons:metabolism, Lipid Peroxidation:physiology, Male, Malondialdehyde:metabolism, Melatonin:metabolism, Neuroprotective Agents:metabolism,.   

OBJECTIVE: It is known that thyrotoxicosis induces lipid peroxidation (LPO). In contrast, propylthiouracil (PTU), a thyrostatic drug is a well-known antioxidant. Also melatonin has been shown to protect against free radical-induced neuronal destruction. At the same time, it is generally accepted that the brain is the most vulnerable tissue to oxidative stress.

METHODS: The goal of the study was to examine the components of LPO, i.e., conjugated dienes (CD), malondialdehyde (MDA) and Schiff's bases (SB), in the brain of male Wistar rats. Two experiments were performed, with two control groups created for each experiment: Group 1--intact animals and Group 2--animals injected with 0.9% NaCl. In Experiment I, the animals received L-thyroxine (L-T4) in a dose of 100 microg/kg BW, i.p., daily, for two weeks (Groups 3-5). After one week of L-T4 treatment, the following agents were added during a subsequent week: Group 4--PTU in drinking water (45 mg/kg BW/day); Group 5--melatonin (5 mg/kg BW, daily). In Experiment II, lasting 7 days, the animals were divided into the following groups: Group 1--intact animals; Group 2--animals injected with 0.9% NaCl; Group 3--PTU in drinking water (45 mg/kg BW/day); Group 4--melatonin (5 mg/kg BW, daily).

RESULTS: In Experiment I, we observed a significantly higher SB level in saline treated animals and a significant increase in both CD and SB levels in rats treated with L-T4, compared to those in non treated control. CD levels were also elevated in rats treated with L-T4, compared to values in the saline only treated animals. Melatonin and PTU reduced CD levels and melatonin diminished SB levels, as compared to those in L-T4-treated rats. In Experiment II, we observed significantly higher CD, SB and MDA levels in saline treated rats, when compared to respective values in non treated control. Melatonin decreased CD levels, when compared to CD levels in both the non treated and saline injected controls. Additionally, melatonin reduced SB levels relative to change in the brains of saline treated rats. Furthermore, PTU decreased CD levels in brain homogenates compared to non-treated animals.

CONCLUSIONS: (1) L-thyroxine administration stimulates LPO in the rat brain; (2) All the examined antioxidants decrease LPO in L-T4-administered animals; (3) All the examined antioxidants reduce the basal LPO; 4) Stress, when induced by handling, intensifies oxidative processes in the organism....

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Journal Article 2005; 26(5): 536-540 PubMed PMID: 16264404 Citation  Keywords:  Animals, Antithyroid Agents, Cholesterol:blood, Folic Acid:blood, Homocysteine:blood, Hyperthyroidism:blood, Hypothyroidism:blood, Lipids:blood, Male, Propylthiouracil, Rats, Rats, Wistar, Thyroid Function Tests, Thyroxine, Vitamin B 12:blood,.   

INTRODUCTION: It is claimed in a limited number of studies carried out on human beings that plasma homocysteine levels increased in hypothyroid patients and decreased in hyperthyroid patients.

OBJECTIVE: The aim of this study is to determine total plasma homocysteine, thyroid function tests, vitamin B12, folic acid and lipid levels and to explore the relations among them in rat models with induced hypothyroidism and hyperthyroidism with a view to investigating whether hypothyroid and hyperthyroid rat models could represent human hypothyroidism and hyperthyroidism models.

MATERIAL AND METHOD: The study included 30 male Wistar Albino species rats with a mean weight of 200 - 250 g. Rats were randomly divided into 3 groups as 1) hypothyroid group, 2) hyperthyroid group and 3) control group. Hypothyroidism was induced by adding 10 mg/kg/day propylthiouracil to rats' drinking water for 30 days. In order to induce hyperthyroidism, rats were administered 10 microg/100 g L-thyroxin ampule via intraperitoneal route for 10 days.

RESULTS: We found that total plasma homocysteine level of the hypothyroid group was significantly lower than those of the control group (p<0.05) and the hyperthyroid group (p<0.001). Total plasma homocysteine level of the hypothyroid group was found insignificantly higher than that of the control group (p>0.05) and significantly higher than that of the hyperthyroid group (p<0.001). We established a significant and positive correlation between total plasma homocysteine level and thyroid hormone levels. We did not identify a significant relation between total plasma homocysteine level and serum folic acid and serum vitamin B12 levels.

CONCLUSION: Our findings are different from the findings reported in human hypothyroidism and hyperthyroidism studies. We believe that hypothyroid and hyperthyroid rat models cannot represent human hypothyroidism and hyperthyroidism models....

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Journal Article 2005; 26(5): 609-616 PubMed PMID: 16264393 Citation  Keywords:  Aluminum:antagonists & inhibitors, Animals, Antioxidants:therapeutic use, Apoptosis:drug effects, Brain:metabolism, Lipid Peroxidation:drug effects, Male, Malondialdehyde:metabolism, Melatonin:therapeutic use, Nerve Degeneration:pathology, Neurofibrils:pa.   

OBJECTIVE: The present study was aimed to investigate: (1) the neurotoxic oxidative damage of orally administered aluminum chloride (AlCl3) in rabbits (Biochemical and morphopathological studies). (2) The effect of melatonin as an antioxidant and free radical scavenger on oxidative neuropathic changes.

METHODS: Thirty-five male rabbits were divided into 4 groups (A, B, C [10 animals each] and D [5 animals]). Group A received AlCl3 (20 mg/l via drinking water for 3 months). Group B received AlCl3 for 3 months then administered with melatonin (10 mg/kg b.w. sc daily for 15 days). Group C received AlCl3 plus melatonin for 3 months. Group D received the solvent and served as control. Malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) as lipid peroxides as well as superoxide dismutase (SOD) as an antioxidant enzyme were measured. Aluminum residue in the brain tissue was measured spectrophotometerically. The morphopathological changes were also examined by light and electron microscopes.

RESULTS: MDA and 4-HAD were significantly increased in group A versus those of controls while significantly decreased in groups B and C compared with those of A group. SOD run in an opposite manner. Aluminum concentration was significantly increased in groups A, B and C when compared with group D while it significantly decreased in groups B and C when compared with that of group A. The neuropathlogical examination in the animals of group A revealed atrophy and apoptosis of the neurons in cerebral cortex and hippocampus. This was associated with neurofibrillary degeneration as well as argyrophilic inclusion. Schwan cell degeneration and nerve fiber demylination were also encountered. The elaboration of lipid peroxidation products, inhibition of antioxidant enzymes and the morphopathological changes were minimized in the Al/Mel treated groups and markedly improved in Al+Mel treated group

CONCLUSION: Chronic aluminum exposure in rabbits had dramatic encephalopathic morphopathological lesions. It enhances the lipid peroxidation production and inhibits the SOD enzyme. Melatonin had a good prophylactic effect as an antioxidant in aluminum encephalopathy....

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Journal Article 2005; 26(5): 617-623 PubMed PMID: 16264392 Citation  Keywords:  Cholesterol:blood, Coronary Disease:epidemiology, Diabetes Mellitus:epidemiology, Disease, Endorphins:physiology, Exercise:physiology, Health, Humans, Hyperlipidemias:epidemiology, Hypertension:epidemiology, Mental Health, Osteoarthritis:epidemiology, Ost.   

: It is known for a long time that exercise increases physical adequacy, has beneficial effects on the general health condition as well as a playing preventing role against various disease states. To decrease the risk of disease and maintain good health, the natural defense system of the organism needs to be strengthened. It is thought that in addition to increasing the body's resistance to disease through the strengthening of the immune system, decreases the convalescence time, increases work efficiency and improves the sportive performance of the individual all which would contribute positively to the national economy. The positive effects of regular exercising of aerobic nature such as strengthening of the immune system, protection against diseases as well as its positive effects on quality of life will help to emphasize the importance of physical exercise and improve the general view of sports by society....

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