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Clinical Trial 2003; 24(3-4): 197-202 PubMed PMID: 14523357 Citation  Keywords:  Adrenocorticotropic Hormone:blood, Adult, Anxiety:physiopathology, Blood Pressure:physiology, Conflict (Psychology), Heart Rate:physiology, Hemodynamics:physiology, Hormones:blood, Human Growth Hormone:blood, Humans, Hydrocortisone:blood, MMPI, Military P.   

OBJECTIVES: Pilots are exposed to the "stress of flight" and the chronically activated stress response may play an important role in circulatory system disease progression. We studied the effect of an experimental mental stress on cardiovascular and neuroendocrine activity, in Air Force Academy cadets, before and after one month intensive course.

DESIGN: Nine cadets were submitted to a psychometric evaluation before Stroop test (ST), including Minnesota Multiphasic Personality Inventory, State and Trait Anxiety Inventory (STAI X1 and X2 form) and Reaction Scheme Test. After ST, subjects completed a STAI X1 form. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP) were monitored and serum prolactin (PRL), growth hormone (GH), adrenocorticotropin (ACTH) and cortisol levels were determined, during ST. The protocol was repeated at the end of the course.

RESULTS: No significant differences were evident in PRL, GH and ACTH levels. Cortisol concentrations were significantly higher before the course. ST did not modify hormone secretion. ST induced a significant and reproducible elevation of HR and SBP. Basal HR, SBP and DBP values were significantly elevated after the course. Two subjects presented a particular psychometric profile, a different cardiovascular response to ST and did not pass the course.

CONCLUSIONS: acute mental stress significantly activated cardiovascular response without modifying endocrine responses, in relation to the psychological profiles. A significant increase of cardiovascular parameters was present after the course, with enhanced dichotomy between the endocrine and sympathetic system, suggesting a careful evaluation and follow-up for circulatory system diseases in cadets....

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Journal Article 2003; 24(3-4): 185-191 PubMed PMID: 14523355 Citation  Keywords:  Cytokines:biosynthesis, Dose-Response Relationship, Drug, Estradiol:pharmacology, Female, Humans, Hydrocortisone:antagonists & inhibitors, In Vitro Techniques, Indicators and Reagents, Interferon-gamma:biosynthesis, Interleukin-10:biosynthesis, Interleuki.   

OBJECTIVES: The purpose of this study was to determine the effects of estradiol and progesterone on interferon-gamma (IFN-gamma), interleukin (IL)-12, IL-10 and tumor necrosis factor-alpha (TNF-alpha) productions in polyclonal activators (phytohemagglutinin+lipopolysaccharide)-stimulated whole blood cultures.

METHODS: Nineteen healthy males and females volunteered in the study. Blood samples were drawn, diluted, and cultured for 24h with different concentrations of estradiol, progesterone or hydrocortisone and then PHA+LPS was added for another 24 h. The supernatant, then, was harvested and assayed for IL-12 p70, IFN-gamma, IL-10 and TNF-alpha.

RESULTS: At preovulatory concentrations, estradiol enhanced significantly IFN-gamma, IL-12 and IL-10, but not TNF-alpha, production levels and reversed the suppressive effect of hydrocortisone in PHA+LPS stimulated whole blood. While IL-10 levels kept increasing at pregnancy estradiol concentrations, IFN-gamma, IL-12 levels and IFN-gamma/IL-10 ratio decreased significantly. No effect of progesterone on IL-12 p70, IFN-gamma, IL-10 and TNF production levels was observed.

CONCLUSIONS: The present study shows that those pregnancy estradiol concentrations (and higher) enhance the production of IL-10 and reduce IL-12, IFN-gamma levels and IFN-gamma/IL-10 ratio in stimulated whole blood cells. Because of the known IL-10 inhibitory actions on T helper (Th) 1 cells and monocytes/macrophages, these high IL-10 levels keep Th2 cytokines favored during pregnancy and may be useful in shifting Th1-mediated autoimmune diseases towards non-pathogenic Th2 pathway....

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Clinical Trial 2003; 24(3-4): 173-180 PubMed PMID: 14523353 Citation  Keywords:  Adult, Affect:physiology, Female, Humans, Hydrocortisone:metabolism, Male, Music:psychology, Photic Stimulation, Radioimmunoassay, Saliva:metabolism, Sex Characteristics, Stress, Psychological:metabolism, Testosterone:metabolism,.   

OBJECTIVES: The aims of the present study were to examine sex-related differences in testosterone (T) and cortisol (C) changes with music listening and visual stress.

SETTING AND DESIGN: Saliva T and C concentrations were measured in 88 healthy college students (44 males and 44 females). These subjects were placed in one of 4 different conditions: (1) 30 min of listening to music, (2) 30 min of listening to music with visual stress (documentary film without sound including violent scenes), (3) 30 min of visual stress without music, and (4) 30 min of silence.

METHODS: All subjects provided two saliva samples, one collected before intervention and the other after intervention. T and C levels were assessed by radio immuno assay (RIA).

RESULTS: There was a significant difference between the sexes in the way music affected T. Music decreased T in males, whereas it increased T in females. As for C, no sex-related differences were found under any of the conditions studied. C decreased with music and increased under other conditions. THE MAIN FINDINGS: Our data suggests that the effects of music and stress on T differ between males and females.

CONCLUSION: Further investigation is necessary to evaluate the relationships between music and other substances, the effect of degree of preference and hormonal changes not only during music listening but also during music plays and creation....

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Journal Article 2003; 24(3-4): 170-172 PubMed PMID: 14523352 Citation  Keywords:  Animals, Antioxidants:therapeutic use, Male, Malondialdehyde:blood, Melatonin:therapeutic use, Rats, Rats, Sprague-Dawley, Reperfusion Injury:pathology, Spermatic Cord Torsion:pathology, Testicular Diseases:pathology, Testis:metabolism,.   

AIM: Torsion of testis, which is a urologic emergency case, is generally treated by surgical detorsion procedure. However, the resulting reperfusion and both ipsilateral and contralateral testis damage caused thereby are important problems. This study aims at investigating the administration of prophylactic melatonin in order to reduce free radical damage that is caused due to reperfusion after experimental testis torsion-detorsion procedure.

MATERIAL AND METHOD: The rats used in the study were allocated to four groups, each containing 10 rats. Rats in Group I had six hours of torsion (ischemia) followed by orchiectomy. Rats in Group II had six hours of torsion, then received melatonin (10 mg/kg/IM) and after that had detorsion (reperfusion). Rats in Group III had detorsion after six hours of torsion and serum physiologic administration (the same volume as melatonin). Torsion and/or detorsion procedures were not applied in Group IV (control). Ipsilateral, contralateral testis and plasma Malondialdehyde (MDA) levels were determined in all groups.

RESULTS: Tissue and plasma MDA levels in the group which had detorsion were found to be significantly higher than those in the group that had orchiectomy only (p<0.02). Ipsilateral and contralateral testis MDA levels were identified to be significantly lower in the group receiving prophylactic melatonin in comparison to the group receiving serum physiologic (p<0.02). Plasma and contralateral MDA levels correlated positively with MDA levels identified in ipsilateral testis in all groups (rs=+0.89, n=40, p=0.000).

CONCLUSION: In cases where testis torsion is identified, administration of melatonin just before torsion may reduce local and systemic free radical damage....

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Journal Article 2003; 24(1-2): 91-95 PubMed PMID: 12743541 Citation  Keywords:  Angiotensin II:pharmacology, Animals, Dehydroepiandrosterone Sulfate:pharmacology, Estradiol:pharmacology, Female, Injections, Intraperitoneal, Inositol 1,4,5-Trisphosphate:metabolism, Male, Pituitary Gland, Anterior:drug effects, Pregnenolone:pharmacolog.   

OBJECTIVES: The present study was designed to test whether various steroid hormones modulate differently angiotensin II (AngII) action in the anterior pituitary in males and females.

MATERIAL AND METHODS: Adult female and male rats were treated with one of the following substances: oil (control), pregnenolone sulfate (PREG-S), 17beta-estradiol benzoate (E2,) progesterone (P), or dehydroepiandrosterone sulfate (DHEA-S), given in intraperitoneal injections for five days in dose of 50 microg per animal per day. Because AngII is known to act in the anterior pituitary through the phosphatidiloinositol breakdown, thus increasing the level of inositol-1,4,5-trisphosphate (IP3), the IP3 concentration was determined 24 hours after the injection in the anterior pituitary homogenate exposed to AngII.

RESULTS: In control animals (without steroids) AngII stimulated concentration of IP(3) stronger in females than in males. E(2) and DHEA-S enhanced AngII effects in both males and females. PREG-S increased AngII-induced IP(3) concentration in females, but not males. Progesterone raised AngII effect on IP(3) concentration in males, only when high concentrations of peptide were used.

CONCLUSION: These results indicate that pituitary sensitivity to AngII stimulation is modulated by steroid hormones and is related to the gender of the animal....

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Journal Article 2003; 24(1-2): 86-90 PubMed PMID: 12743540 Citation  Keywords:  Animals, Antioxidants:metabolism, Glutathione Peroxidase:metabolism, Male, Malondialdehyde:metabolism, Melatonin:pharmacology, Nitric Oxide:metabolism, Rats, Rats, Wistar, Superoxide Dismutase:metabolism, Testis:drug effects, Varicocele:metabolism,.   

OBJECTIVES: The pathophysiology of the testicular damage in varicocele have not been completely understood. There are several studies concerning the effects of increased seminal reactive oxygen species (ROS) and the role of nitric oxide (NO) in infertile patients with varicocele and antioxidants have been used successfully to decrease oxidative stress in testis. In this study, we determined the effects of melatonin on testicular NO and antioxidant enzyme levels and investigated whether melatonin can prevent or diminish testicular damage in adult rats with experimentally induced unilateral varicocele.

METHODS: Thirty adult male Wistar rats were randomly divided into three groups. In group I, using midline incision left renal vein was exposed but not tied. In group II, left renal vein was partially ligated to create varicocele. In group III, after creation of varicocele, daily and fresh-prepared melatonin was administered intraperitoneally for 4 weeks. Histopathological examination was performed and tissue malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and tissue NO levels were determined.

RESULTS: In group II, there were severe degenerative changes of the germinal epithelium and atrophy of the seminiferous tubules in left testis. In group III, in which rats received melatonin intraperitoneally, there were focal areas showing decrease in spermatogenesis and some degenerative changes. Similarly, the levels of ROS and NO were significantly increased in testicular tissue of rats in group II, whereas group III rat testes in which melatonin was administered, showed increased antioxidant enzyme activity and decreased NO levels.

CONCLUSION: Infertility related to varicocele has multiple pathophysiological mechanisms and the effect of ROS, NO and antioxidant defense system are contributing factors in the disease state. Melatonin, a potent free radical scavenger, administration might be helpful in the prevention or at least, in the delay of the severe effects of varicocele on testicular tissue....

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Clinical Trial 2003; 24(1-2): 50-53 PubMed PMID: 12743532 Citation  Keywords:  Adult, Apomorphine:pharmacology, Disease Progression, Human Growth Hormone:blood, Humans, Hydrocortisone:blood, Male, Neoplasm Metastasis, Neoplasms:physiopathology, Neurosecretory Systems:drug effects, Prolactin:blood,.   

OBJECTIVES: The clinical approach of the Psychooncology is generally limited to the investigation of the only psychological status of cancer patients, without taking into consideration the well demonstrated cancer progression-related psychoneuroendocrine alterations, namely consisting of a progressive decline in the pineal endocrine function and an anomalous activity of brain opioid system. The endocrine response to apomorphine, a dopaminergic agent, has been proven to reflect the dopaminergic sensitivity, which would be involved at least in part in pleasure-related neurochemical mechanisms. The present study was performed to analyze the endocrine response to apomorphine in metastatic cancer patients, as a preliminary approach to the investigation of pleasure-related neuroendocrine mechanisms in human neoplasms.

MATERIALS & METHODS: The study included 10 metastatic cancer male patients and 6 male volunteers as a control group. Apomorphine was given orally at 0.01 mg/kg body weight in the morning, and venous blood samples were collected before, and at 20, 60 and 120 minutes after apomorphine administration. The endocrine analysis consisted of the measurement of serum levels of GH, PRL and cortisol.

RESULTS: All cancer patients presented alterations involving one or more endocrine responses to apomorphine. GH and cortisol mean levels after apomorphine were significantly higher in controls than in cancer patients, whereas no substantial difference occurred in those of PRL.

CONCLUSIONS: This preliminary study, by showing an altered endocrine response to apomorphine in metastatic cancer patients, would suggest that cancer progression may be associated with an altered dopaminergic sensitivity. Because of the involvement of the dopaminergic system in pleasure-related neurochemical mechanisms, this finding would demonstrated that the decline in the perception of pleasure with cancer progression may depend not only on psychological factors, but also, at least in part, on psychochemical alterations occurring during the clinical course of the neoplastic disease....

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Journal Article 2002; 23(5-6): 417-425 PubMed PMID: 12500163 Citation  Keywords:  Alkaline Phosphatase:blood, Animals, Biomarkers:blood, Bone and Bones:metabolism, Calcium:metabolism, Circadian Rhythm:physiology, Collagen Type I, Hormones:metabolism, Hydroxyproline:urine, Male, Melatonin:metabolism, Peptide Fragments:blood, Peptides, P.   

BACKGROUND: The mechanism of generating and synchronizing daily rhythms of bone and mineral metabolism markers has not been entirely explained. Most studies indicate that LD cycle and/or feeding schedules provide important synchronizers of these rhythms. It seems that endogenous factors, including systemic and local hormones can be important in the mechanism of dependence of bone and mineral metabolism parameters rhythms on LD cycle and feeding schedule.

OBJECTIVE: To assess the relationship between the daily profile of chosen biochemical parameters of bone and mineral metabolism (serum ALP, PICP, ICTP and iP and urinary excretion of HYP and total calcium) and daily secretion of MEL, GH/IGF-I axis activity and parathyroid, thyroid, adrenal cortex and gonads function in 48 adult male rats.

METHODS: Material for studies was collected every 3 hours within a day. Hormones, PICP and ICTP concentrations were determined with the use of RIA method and ALP, HYP, total calcium and iP values--spectrophotometrically.

RESULTS: Existence of a negative correlation between daily oscillations of studied markers of osteogenesis (ALP and PICP) and daily profile of MEL and PTH secretion and positive with daily fluctuations of GH and IGF-I was shown. Moreover, ALP values correlated negatively with daily oscillations of CT. Concentrations of bone resorption markers (ICTP, HYP and total calcium) correlated negatively with daily fluctuations of MEL and positively with GH, IGF-I and thyroid hormones.

CONCLUSION: The present results suggest that physiological daily rhythmicity of PTH, MEL, GH, IGF-I and thyroid hormones most probably play an important role in regulating the daily rhythm of biochemical markers of bone metabolism....

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