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Journal Article 2006; 27(1-2): 35-52 PubMed PMID: 16648818 Citation  Keywords:  Animals, Antioxidants, Blindness:epidemiology, Carcinogens:toxicity, Circadian Rhythm:physiology, Environmental Pollution:adverse effects, Humans, Light, Melatonin:physiology, Neoplasms:epidemiology, Reproduction:physiology, Risk,.   

: At present, light pollution (exposure to light-at-night) both in the form of occupational exposure during night work and as a personal choice and life style, is experienced by numerous night-active members of our society. Disruption of the circadian rhythms induced by light pollution has been associated with cancer in humans. There are epidemiological evidences of increased breast and colon cancer risk in shift workers. An inhibition of the pineal gland function with exposure to the constant light (LL) regimen promoted carcinogenesis whereas the light deprivation inhibits the carcinogenesis. Treatment with pineal indole hormone melatonin inhibits carcinogenesis in pinealectomized rats or animals kept at the standard light/dark regimen (LD) or at the LL regimen. These observations might lead to use melatonin for cancer prevention in groups of humans at risk of light pollution....

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Journal Article 2006; 27(1-2): 281-287 PubMed PMID: 16648811 Citation  Keywords:  Analgesics, Animals, Antidepressive Agents, Second-Generation:pharmacology, Blood Glucose:metabolism, Diabetes Complications:drug therapy, Diabetes Mellitus, Experimental:blood, Female, Fluoxetine:pharmacology, Hyperalgesia:drug therapy, Male, Mice, Mice,.   

OBJECTIVES: Clinical and experimental trials have demonstrated that some of selective serotonin reuptake inhibitors (SSRIs) have some suspicious effects on blood glucose levels in different directions. Especially fluoxetine and sertraline are studied in this point of view. These drugs are also used in treatment of depression and peripheral neuropathy in diabetic patients. Paroxetine and fluoxetine, members of this drug group, besides having antidepressant effects were shown to have antinociceptive effects in animals and humans. They can be used in the treatment of chronic pain as an adjuvant drug or alone. But less is known about their actions on pain in case of diabetes. The aim of this study is to investigate the antinociceptive effects of fluoxetine and paroxetine in diabetic and non-diabetic mice while monitoring their effects on blood glucose levels.

METHODS: Mice of either sex were randomly used in experiments. The antinociceptive effects of paroxetine and fluoxetine were evaluated using hot plate test both in diabetic and non-diabetic mice. The effects of these drugs on blood glucose levels were also evaluated in another group of mice both in diabetic and non-diabetic mice.

RESULTS: Fluoxetine and paroxetine showed significant antinociceptive effect at all doses and at all times tested in non-diabetic mice, but they could not successfully show this effect in diabetic mice. They also had controversial effects on blood glucose levels.

CONCLUSION: Although they showed increasing or decreasing effects on blood glucose levels in non-diabetic and diabetic mice, they showed antinociception on hot-plate test showing dissociation between blood glucose levels and analgesia....

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Journal Article 2006; 27(1-2): 219-224 PubMed PMID: 16648810 Citation  Keywords:  3-Hydroxysteroid Dehydrogenases:genetics, Adrenal Cortex Hormones:metabolism, Alleles, Child, China:epidemiology, Female, Gene Frequency, Genotype, Gonadal Steroid Hormones:blood, Humans, Insulin Receptor Substrate Proteins, Molecular Sequence Data, Phosp.   

OBJECTIVES: In order to investigate whether the variances in the candidate genes (Insulin receptor substrate IRS-1, beta3-adrenergic receptor ADRB3, 3 beta-hydro-xysteroid dehydrogenase HSD3B2, glucocorticoid receptor GRL and 21-hydroxylase CYP21) which affect the metabolism of adrenal steroids hormone and body composition, are associated with precocious puberty in Chinese girls.

METHODS: PCR-RFLP analysis method was applied in the typing of six activity SNPs in five genes in two groups: 176 precocious puberty girls as case and 192 healthy girls as control.

RESULTS: The typing results showed that the frequencies of the allele CYP21 L282 polymorphism were 32.7% and 32.6% in case and control groups (P=0.518), respectively. For IRS-1 R972, they were 0.6% in cases and 2.3% in controls (P=0.043), for ADRB3 R64, 13.6% in cases and 12% in controls (P=0. 378), and for GRL S363, 7.4% in cases and 5.73% in controls (P=0.335). No sample in the two groups carries the variation of CYP21 I172N and HSD3B2 L236S.

CONCLUSION: Among these six activity SNPs in five candidate genes, IRS-1 972R was statistically associated with the onset time of puberty in Chinese girls. In order to confirm whether the candidate genes have any other activity SNPs that are associated with the onset time of puberty in Chinese girls, resequencing of these candidate genes is needed in following time....

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Journal Article 2006; 27(1-2): 81-84 PubMed PMID: 16648798 Citation  Keywords:  Aflatoxin B1:antagonists & inhibitors, Animals, Antioxidants:pharmacology, Apoptosis:drug effects, Cell Death:drug effects, Injections, Intraperitoneal, Male, Melatonin:pharmacology, Rats, Rats, Wistar, Thyroid Gland:cytology,.   

OBJECTIVES: Apoptosis, or programmed cell death, is a normal component in the development of multicellular organisms and is essential for many physiological processes. Apoptosis is a process in which cells play an active role in their own death (apoptosis is often referred to as "cell suicide"). Disturbances of apoptosis regulation can result in many diseases. Certain substances (for example--aflatoxin B1; AFB1) can induce apoptosis in various organs and tissues. Melatonin (Mel) is a hormone (indoleamine) which has antioxidant, antiproliferative and, potentially, anticancerogenic activities. The aim of our study was to examine the influence of late-afternoon (1600-1800) intraperitoneal (i.p.) Mel injections, administered for 3 weeks, on the process of apoptosis in male Wistar rat thyroid follicular cells (TFC); Mel was injected alone or together with AFB1 (i.p., also once daily for 3 weeks).

METHODS: In order to assess the process of apoptosis, evaluated in microscopic preparations of rat thyroids, an In Situ Cell Death Detection, POD Kit [Roche, GER] and the DAKO Liquid DAB Substrate-Chromogen System [DakoCytomation, USA] were employed.

RESULTS: Aflatoxin B1 increased the apoptotic index (I(apopt)) in rat TFC, in comparison to controls (p<0.001). The I(apopt) value in the rats, receiving Mel and AFB1 injections, was statistically lower, as compared to the value of the examined index in the group of AFB1-treated animals (p<0.001). No statistically significant differences of I(apopt) value were observed between the Mel-treated group of animals and the controls.

CONCLUSION: Melatonin can assumingly regulate the growth of cells and tissues by influencing the process of apoptosis....

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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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Journal Article 2006; 27(1-2): 189-197 PubMed PMID: 16648791 Citation  Keywords:  Adolescent, Adult, Aged, Antioxidants:therapeutic use, Biocompatible Materials:adverse effects, Cell Separation, Chronic Disease, Dental Materials:metabolism, Down-Regulation, Enzyme-Linked Immunosorbent Assay, Fatigue Syndrome, Chronic:etiology, Female, .   

OBJECTIVES: This study was done to evaluate the results and clinical relevance of an optimized lymphocyte proliferation test, MELISA, for metal-induced inflammation in patients with CFS-like symptoms. The treatment of patients consisted of the replacement of incompatible dental materials (RID) together with supportive anti-oxidant therapy.

DESIGN OF THE STUDY: 513 patients were tested by MELISA at the beginning of the study. Out of this group, 248 patients were available for follow-up MELISA after RID.

METHODS: In MELISA, lymphocytes are isolated from the blood and cultivated with different metal salts in tissue culture medium containing 10% inactivated human AB+ serum or autologous serum. After 5 days, the presence of metal-reactive lymphocytes are measured by isotope labelling of newly formed DNA in growing lymphoblasts and evaluated by calculating the Stimulation Index.

RESULTS: Nickel was the most common sensitizer, followed by inorganic mercury, thimerosal, lead, cadmium, palladium and gold. After RID treatment, a decrease of metal-specific lymphocyte responses in patients who reacted to metals at the beginning of the study could be observed. The cultivation of lymphocytes in autologous and homologous serum did not significantly affect the results. Simultaneous, the health status of patients improved as well.

CONCLUSIONS: Replacement of incompatible dental materials resulted in down-regulation of metal-induced lymphocyte sensitivity in vitro, as well as in the improvement of health status of majority of patients with unspecific CFS-like symptoms....

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Journal Article 2006; 27(1-2): 247-252 PubMed PMID: 16648789 Citation  Keywords:  Adolescent, Adult, Exercise:physiology, Exercise Test, Humans, Testosterone:blood, Thyroid Hormones:blood, Thyrotropin:blood, Thyroxine:blood, Triiodothyronine:blood, Wrestling:physiology, Zinc:pharmacology,.   

OBJECTIVES: The present study aims to investigate how exhaustion exercise affects thyroid hormones and testosterone levels in elite athletes who are supplemented with oral zinc sulfate for 4 weeks.

METHODS: The study included 10 male wrestlers, who had been licensed wrestlers for at least 6 years. Mean age of the wrestlers who volunteered in the study was 18.70 +/- 2.4 years. All subjects were supplemented with oral zinc sulfate (3 mg/kg/day) for 4 weeks in addition to their normal diet. Thyroid hormone and testosterone levels of all subjects were determined as resting and exhaustion before and after zinc supplementation.

RESULTS: Resting TT3, TT4, FT3, FT4 and TSH levels of subjects were higher than the parameters measured after exhaustion exercise before zinc supplementation (p<0.05). Both resting and exhaustion TT3, TT4 and FT3 values after 4-week zinc supplementation were found significantly higher than both of the parameters (resting and exhaustion) measured before zinc supplementation (p<0.05). Resting total testosterone and free testosterone levels before zinc supplementation were significantly higher than exhaustion levels before zinc supplementation (p<0.05). Both resting and exhaustion total and free testosterone levels following 4-week zinc supplementation were found significantly higher than the levels (both resting and exhaustion) measured before zinc supplementation (p<0.05).

CONCLUSION: Findings of our study demonstrate that exhaustion exercise led to a significant inhibition of both thyroid hormones and testosterone concentrations, but that 4-week zinc supplementation prevented this inhibition in wrestlers. In conclusion, physiological doses of zinc administration may benefit performance....

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Clinical Trial 2005; 26(6): 839-842 PubMed PMID: 16380701 Citation  Keywords:  Antioxidants:administration & dosage, Copper:blood, Coronary Artery Bypass, Extracorporeal Circulation:adverse effects, Humans, Inflammation:blood, Leptin:blood, Preoperative Care, Stress, Physiological:blood, Zinc:administration & dosage,.   

OBJECTIVE: The role of leptin in the acute stress response to extracorporeal circulation has been well documented, however, the relationship between leptin and zinc has not been investigated previously. We aimed to research the circulating leptin, zinc, and copper levels before, during, and after the extracorporeal circulation, and effect of preoperative zinc administration to these.

METHODS: Twenty patients who were taken to elective coronary artery bypass grafting operations using extracorporeal circulation were taken to this research and divided into two equal groups (n1, n2). In both groups blood samples were taken just before the operation (T0), at the end of operation (T1), and at the first postoperative day (T2). In the second group (n2) oral zinc (50 mg, once a day) was administered to patients for 5 days, preoperatively. The serum leptin, zinc, and copper levels were studied.

RESULTS: In group n1 circulating leptin levels were significantly increased at T2 when compared to T0 and T1 (p<0.05); zinc levels were decreased at T2 when compared to T0 and T1 (p<0.05); copper levels were decreased at T2 when compared to T0 (p<0.05), and decreased at T1 when compared to T0 (p<0.05). In group n2 circulating leptin levels were significantly increased at T2 when compared to T0 and T1 (p<0.05); zinc levels were decreased at T2 when compared to T0 and T1 (p<0.05); copper levels were increased at T2 when compared to T1 (p<0.05).

CONCLUSIONS: These results indicate that circulating leptin levels increase after the extracorporeal circulation as an acute response, while zinc and copper levels decrease at the same period. Preoperative zinc administration does not prevent the leptin response after extracorporeal circulation....

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