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Journal Article 2007; 28(5): 666-670 PubMed PMID: 17984941 Citation  Keywords:  Analysis of Variance, Animals, Dose-Response Relationship, Drug, Estradiol:physiology, Female, Melatonin:administration & dosage, Nerve Degeneration:pathology, Neural Conduction:physiology, Neuroprotective Agents:administration & dosage, Ovariectomy, Post.   

OBJECTIVES: Melatonin is a potent antioxidant agent and an anti-aging hormone. Serum melatonin level declines during the menopause. Estradiol, a neuroprotective ovarian hormone, also decreases during the menopause. The purpose of this study is to evaluate the effect of melatonin supplementary on peripheral nerve function in the ovariectomized (OVX)-aged rats.

METHODS: Randomly selected OVX-aged Wistar rats received injections of melatonin (5 or 20 mg/kg) daily either two or six weeks. Nerve conduction velocities and distal latencies were determined from the propagation of action potential recorded by using an extracellular electrophysiological technique.

RESULTS: The mean distal latencies of melatonin-treated groups were shorter than that of the control group. Thus, the nerve conduction velocity was significantly greater in both two weeks and six weeks melatonin treated groups as compared to the controls (p<0.001).

CONCLUSION: Melatonin alleviates the electrophysiological properties of the sciatic nerve in OVX-aged rats. Thus, melatonin supplementary may have a potential clinical application for the treatment of postmenopausal peripheral nerve degeneration....

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Comparative Study 2007; 28(5): 614-620 PubMed PMID: 17984940 Citation  Keywords:  Adrenal Medulla:drug effects, Adrenergic Uptake Inhibitors:pharmacology, Adrenocorticotropic Hormone:blood, Analysis of Variance, Animals, Corticosterone:blood, Epinephrine:blood, Fluoxetine:pharmacology, Hypothalamo-Hypophyseal System:drug effects, Male,.   

OBJECTIVE: To estimate the influence of long-term treatment with noradrenergic and serotonergic reuptake inhibitors on activity of pituitary-adrenocortical and sympatho-adrenomedullar systems in animals, we compared the effects of maprotiline (a selective inhibitor of noradrenaline reuptake) and fluxilan (a selective inhibitor of serotonin reuptake) on plasma noradrenaline (NA), adrenaline (A), adrenocorticotropic hormone (ACTH) and corticosterone (CORT) levels in unstressed control and rats exposed to chronic unpredictable mild stress (CUMS).

METHODS: Plasma NA and A were assayed by a radioenzymatic method. Plasma CORT was measured using RIA kits and plasma ACTH by a chemiluminescent method.

RESULTS: CUMS did not affect blood plasma NA, A and ACTH content, but elevated plasma CORT level. Maprotiline elevated plasma NA content both in unstressed control and CUMS group, whereas plasma A remained unchanged. Fluxilan acted significantly increasing plasma NA and A concentrations both in control and CUMS rats. Neither maprotiline nor fluxilan affected plasma ACTH level both in unstressed control and CUMS animals. Plasma CORT level in unstressed control rats remained unchanged after maprotiline and fluxilan treatment, while being significantly decreased in CUMS rats.

CONCLUSION: Chronic treatment of adult rat males with maprotiline, a noradrenaline reuptake inhibitor activated sympathoneural system. On the other hand, fluxilan, a serotonin reuptake inhibitor activated both sympathoneural and adrenomedullar system, whereas both antidepressants desensitized HPA axis. The findings described here suggest that elevated plasma catecholamines my contribute to adverse effects of these drugs on cardiovascular parameters during antidepressant therapy....

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Comparative Study 2007; 28(5): 575-579 PubMed PMID: 17984939 Citation  Keywords:  Adult, Aged, Circadian Rhythm:physiology, Humans, Male, Middle Aged, Nerve Growth Factors:blood, Oxygen:blood, Polysomnography, S100 Calcium Binding Protein beta Subunit, S100 Proteins:blood, Severity of Illness Index, Sleep Apnea, Obstructive:blood, Stat.   

OBJECTIVE: Responsible for sleep brain perfusion changes, obstructive sleep apnea (OSA) constitutes a cardiovascular risk. To find out about any diffuse damage to the brain tissue, we studied the S100B protein, whose serum level is known to rise in stroke and craniocerebral trauma.

METHODS: 60 men (mean age 51.7+/-11.8 years) referred to us for OSA without any major comorbidity were examined polygraphically. S100B was determined with electrochemiluminiscence immunoassay (ECLIA) from evening and morning blood samples.

RESULTS: All sixty men were diagnosed with OSA. The difference between the evening level of S100B 0.068+/-0.030 microg/l and the morning level 0.059+/-0.029 microg/l was significant (p=0.0004). Patients with mild OSA were found to have the evening S100B 0.063+/-0.023 microg/l, the morning level 0.042+/-0.012 microg/l, the difference being significant (p=0.00051). In moderate OSA the difference between the evening -0.070+/-0.017 microg/l and morning levels -0.055+/-0.025 microg/l was less significant (p=0.043). In severe OSA no difference was found between the evening and morning concentrations of S100B (0.070+/-0.036 microg/l and 0.070+/-0.031 microg/l respectively). The difference between the evening and morning S100B levels correlated negatively with AHI and ODI and positively with basal saturation and average minimal oxygen saturation.

CONCLUSIONS: Sleep with signs of severe OSA influences S100B protein release....

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Comparative Study 2007; 28(5): 621-628 PubMed PMID: 17984937 Citation  Keywords:  Acromegaly:blood, Adult, Aged, Aged, 80 and over, Bone Density:physiology, Bone Resorption:blood, Estradiol:blood, Female, Follicle Stimulating Hormone:blood, Human Growth Hormone:blood, Humans, Hypogonadism:blood, Insulin-Like Growth Factor I:analysis, L.   

OBJECTIVES: The aim of our study was to evaluate bone metabolism and bone mineral density (BMD), and to indicate the main determinants of these parameters in a large group of patients with active acromegaly.

METHODS: A group of 121 active acromegalics, aged 23-80 years, from a single endocrinological center was studied. Serum GH, IGF-I, LH, FSH, PRL, estradiol/testosterone, osteocalcin (OC), type I collagen carboxyterminal telopeptide (ICTP) as well as BMD by DXA at spine L2-L4, femoral neck, Ward's triangle and trochanter were measured.

RESULTS: Serum OC and ICTP concentrations were elevated (mean+/-SEM: 31.7+/-2.2 microg/L, p<0.001; 7.3+/-0.5 microg/L, p<0.001, respectively), and positively correlated with each other, as well as with IGF-I. BMD (Z-scores) was increased at L2-L4, femoral neck and trochanter (0.35+/-0.15, p=0.016; 0.60+/-0.11, p<0.001 and 0.59+/-0.13, p<0.001; respectively). The main determinants of Z-scores and ICTP were gonadal status and gender, while of OC was IGF-I. Eugonadal acromegalics had higher than normal serum OC and ICTP, as well as Z-scores at all measured sites. Hypogonadal patients (2/3 of the population) had significantly higher serum ICTP concentrations and lower BMD at all sites, when compared to eugonadal acromegalics. Thirty five percent of hypogonadal subjects had T-score<-1. Men had significantly higher serum ICTP and lower Z-scores than women.

CONCLUSIONS: (i) In active acromegaly, enhanced IGF-I-dependent bone turnover and increased BMD is observed. (ii) In hypogonadal acromegalics, high bone resorption decreases BMD and may lead to osteoporosis. (iii) There is a smaller increase in bone resorption and greater increase in BMD in women with acromegaly than in men....

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Journal Article 2007; 28(5): 610-613 PubMed PMID: 17984936 Citation  Keywords:  Adjustment Disorders:blood, Adrenocorticotropic Hormone:blood, Adult, Anxiety Disorders:blood, Circadian Rhythm:physiology, Crime Victims:psychology, Dehydroepiandrosterone:blood, Depressive Disorder:blood, Female, Humans, Hydrocortisone:blood, MMPI, Male.   

OBJECTIVES: Evidence in the literature suggests stress-related changes of hypothalamus-pituitary-adrenal (HPA) axis in mobbing. We investigated the association between HPA activity and psychological profiles in mobbing, using a multidisciplinary approach.

DESIGN: Forty-eight victims of mobbing were evaluated by a working group of the Departments of Occupational Medicine, Psychiatry and Internal Medicine. After an informed consent, a detailed occupational history, a psychiatric interview with Minnesota Multiphasic Personality Inventory 2 (MMPI-2) administration and a blood sample (8:00 AM) for the determination of basal adrenocorticotropin (ACTH), cortisol and dehydroepiandrosterone sulphate (DHEAS) plasma levels were collected. Twenty-six patients received an overnight dexamethasone (dex) test.

RESULTS: Mean ACTH, cortisol and DHEAS levels were within normal ranges. The dex-test response was normal, with a significant hormone suppression (ACTH p<0.001, cortisol p<0.001, DHEAS p<0.001). The correlations between basal hormones and the psychometric scales of MMPI-2 revealed that cortisol was significantly and negatively related to Psychasthenia (Pt, p=0.003) and Depression (D, p=0.006), while DHEAS showed a significant negative correlation to Hysteria (Hy, p=0.008). Basal ACTH levels were not significantly related to psychometric scales.

CONCLUSION: A significant inverse correlation between morning plasma cortisol levels and psychometric parameters in victims of mobbing with adjustment disorders was observed. A larger group of patients is necessary to identify and validate a cut-off cortisol level that may become an innovative biological parameter for the diagnosis and follow-up in victims of mobbing....

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Journal Article 2007; 28(5): 662-665 PubMed PMID: 17984929 Citation  Keywords:  Adolescent, Adult, Altruism, Amylases:metabolism, Decision Making:physiology, Games, Experimental, Humans, Male, Reference Values, Reward, Saliva:metabolism, Self Concept, Social Perception,.   

OBJECTIVE: Little is known regarding the relationship between social evaluation-induced neuroendocrine responses and generosity in game-theoretic situations. Previous studies demonstrated that reputation formation plays a pivotal role in prosocial behavior. This study aimed to examine the relationships between a social evaluation-induced salivary alpha-amylase (sAA) response and generosity in the dictator game. The relationship is potentially important in neuroeconomics of altruism and game theory.

METHODS: We assessed sAA and allocated money in the dictator game in male students with and without social evaluation. RESULTS Social evaluation-responders allocated significantly more money than controls; while there was no significant correlation between social evaluation-induced sAA elevation and the allocated money.

CONCLUSIONS: Social evaluation significantly increases generosity in the dictator game, and individual differences in trait characteristics such as altruism and reward sensitivity may be important determinants of generosity in the dictator game task....

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Clinical Trial 2007; 28(5): 708-712 PubMed PMID: 17984925 Citation  Keywords:  Adolescent, Adult, Analysis of Variance, Dietary Supplements, Exercise:physiology, Humans, Magnesium:administration & dosage, Martial Arts:physiology, Physical Exertion:physiology, Reference Values, Rest:physiology, Statistics, Nonparametric, Thyroid Horm.   

: The effect of magnesium on thyroid hormones of sedentars and sportsperson in Tae-Kwon-Do, has been investigated in a 4-weeks training program. Group 1 consisted of sedentars receiving 10 mg/kg/day Mg for 4 weeks. Group 2 consisted of subjects receiving magnesium (Mg) supplement and practicing Tae-Kwon-Do for 90-120 min/day, for five days a week. Group 3 consisted of subjects practicing Tae-Kwon-Do but receiving Mg supplements. TSH levels increased with training and Mg supplementation (p<0.05). Mg increased FT3 values. (p<0.05). TT3 values of groups reduced in all groups (p<005). After supplementation, group 1 had higher TT4 values than groups 1 and 3 and the group 2 had higher TT4 values than the third group (p<005). Results of this research show that training until exhaustion causes reduction in thyroid hormone activity in sedentars and sportsperson. It has been established that Mg supplementation however, prevents reduction in thyroid hormone activity in sedentars and sportsperson....

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Journal Article 2007; 28(4): 410-416 PubMed PMID: 17693988 Citation  Keywords:  Adolescent, Adolescent Development:physiology, Anorexia Nervosa:complications, Blood Pressure:physiology, Blood Pressure Monitoring, Ambulatory, Bradycardia:etiology, Case-Control Studies, Child, Circadian Rhythm:physiology, Estradiol:blood, Female, Folli.   

OBJECTIVES: Anorexia nervosa (AN) is characterized by marked neuroendocrine and autonomic dysfunctions. In the recent studies using automatic blood pressure monitoring (ABPM), lower BP values and lack of circardian variation of BP in anorectic patients were demonstrated. Unfortunately effects of hormonal changes, that may explain BP abnormalities were not analysed together.

DESIGN: The aim of our study was the assessment of ABPM and hormonal status in anorectic girls.

SETTINGS: The study was performed on hospitalized 25 female anorectic adolescents aged 12-18 years. Control group was 17 age and height matched girls with normal weight and negative history for hypertension. ABPM was performed between 5 and 7 day of hospitalization, every 30 minutes during active period and every 60 minutes during sleep. Hormones (FSH, LH, estradiol, cortisol and fT4) serum concentrations were also evaluated.

RESULTS: Mean systolic BP values were significantly lower in patients with AN in comparison to controls. Maximal diastolic and mean arterial pressure values for the whole day and active period but not for sleep were lower in AN than in controls. Anorectic girls showed tendency to night-time bradycardia. Moreover, there were no physiological circadian variations of BP in AN.

CONCLUSIONS: We conclude that hormonal regulation of blood pressure and heart rate in anorectic patients is at least partially preserved. Lower blood pressure values, bradycardia and lack of physiological night fall of BP in anorectic patients may result from altered autonomic system function resulting from hormonal disturbances and other centrally mediated mechanisms....

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