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Journal Article 2004; 25(3): 196-200 PubMed PMID: 15349085 Citation  Keywords:  Acute Disease, Animals, Corticosterone:blood, Encephalomyelitis, Autoimmune, Experimental:blood, Male, Rats, Rats, Wistar, Testosterone:blood, Time Factors,.   

OBJECTIVES: Experimental autoimmune encephalomyelitis (EAE) was induced to investigate the levels of circulating total testosterone (TT) and the possible association of corticosterone with the steroid-producing capacity of the testes.

SETTING AND DESIGN: We determined gonad weights, serum TT and corticosterone levels during the development of EAE in male rats.

METHODS: Active EAE was induced in young male Wistar rats by injection of whole myelin in complete Freund's adjuvant. All the rats were weighted and monitored daily for clinical signs and blooded during different phases of the disease. Serum TT was measured by radioimmunoassay and circulating corticosterone was determined using a competitive enzyme immunoassay. Also testes and seminal vesicles were removed to determine their weights.

RESULTS: Seminal vesicle weights and serum TT levels diminished during the acute stage of the disease in all EAE rats and then they began gradually to increase, reaching the normal values at the post-recovery phase. Concomitantly a significant increase in serum corticosterone levels was observed during the acute EAE and the post-recovery phase was accompanied by a decline in corticosterone levels.

MAIN FINDING: Our results indicated an inverse correlation between serum TT and corticosterone levels during the acute EAE. Moreover, the diminution of TT was not a consequence of an alteration of the testes induced by anti-myelin antibodies neither contributed by apoptosis of testis cells by exposure to corticosterone.

CONCLUSIONS: The negative correlation between corticosterone and TT levels associated to EAE may be relevant in understanding the association of the endocrine system and the development of autoimmune demyelinating diseases....

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Clinical Trial 2004; 25(1-2): 141-147 PubMed PMID: 15159698 Citation  Keywords:  Brain Ischemia:cerebrospinal fluid, Humans, Interleukin-1:cerebrospinal fluid, Interleukin-6:cerebrospinal fluid, Intracranial Aneurysm:cerebrospinal fluid, Rupture, Spontaneous, Subarachnoid Hemorrhage:cerebrospinal fluid, Time Factors, Vasospasm, Intrac.   

: Cytokines play a key role in mutual influence of the immunological, endocrine and CNS systems. It has been proven that proinflammatory ILs may intensify the cascade of biochemical changes in ischemic brain damage. Vasospasm, which may accompany SAH and often coexists with symptoms of DINDs, is the cause of ischemic changes in the brain. It is thought that immunological mechanisms may be one of the causes of degenerative-productive changes in vessel walls, in delayed vasospasm following SAH, which lead to substantial vasospasm and in consequence too cerebral ischemia. In the randomly selected group of patients, who underwent surgical treatment after aneurysmal SAH, we determined the concentration of IL-1 beta and IL-6 in CSF in the periods between Days 0 to 3; 4 to 7; and 8 to 15 after the occurrence of SAH. The presence and dynamics of development of vasospasm were assessed on the basis of increasing DINDs as well as CT and cerebral angiography. We examined the concentrations of ILs in CSF using radioimmunological methods, applying commercially available tests for their assessment. We found that in the period between 8 and 15 days after SAH, in increasing delayed vasospasm and DINDs, here is a statistically significant increase concentration of IL-1 beta in CSF (105.4 +/- 46.9 pg x ml-1; p<0.005), and no significant changes in patients without vasospasm and neurological deficits. On the other hand, we noted a statistically significant increase concentration of IL-6 in CSF (4802 +/- 1170 ng x ml-1; p<0.05) only in the acute phase after SAH (Days 0-3) in patients in poor clinical condition, in whom delayed vasospasm and cerebral ischemia developed later. This increase of ILs level in CSF is probably related to the intensity of the SAH, and secondarily aggravates the vasospasm and ischemic changes in the brain....

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Journal Article 2003; 24(5): 283-292 PubMed PMID: 14646999 Citation  Keywords:  Cytokines:physiology, Humans, Neuroimmunomodulation:physiology, Neurosecretory Systems:immunology, Stress, Psychological:immunology, Time Factors,.   

OBJECTIVES: Previously, a large number of studies reported that psychological stress and psychiatric illness reduces immune responsiveness. However, it turned out that stress reduces immune responsiveness is an oversimplified statement because the interactions between central nervous system, endocrine system and the immune system are undoubtedly complex. Therefore, this study aims in reviewing mental stress models (e.g. brief and written examination stress as subacute and acute type of stressor) that have been utilized to understand the effect of stress on the neuroendocrine and immune systems.

METHODS: The published findings from human mental stress models on catecholamines, cortisol, prolactin levels and on T helper (Th) 1 and 2-induced cytokines are presented and discussed with respect to the in vitro and in vivo effects of glucocorticoids, catecholamines, and prolactin on the induction of cytokines.

RESULTS: This review shows evidence that short-time (minutes) or preparation to a written examination, in those students who are stressed, induces the production of proinflammatory cytokines which may be related to Th1 response. However, longer mental stress (days) causes dysregulation in the immune function by shifting the cytokine response to Th2 response.

CONCLUSIONS: The outcome from neuroendocrine and immune function prior to, following and after mental stress depends on multiple variables most importantly on the amount of stress, exposure time, coping behavior and adjustment of the individual. A few minutes of stress may improve immune performance but longer times of mental stress have detrimental effects that may lead to loss of immune integrity. Furthermore, studies on stress and common heath problems are necessary to increase our knowledge and understanding of the mechanisms responsible for producing neuroendocrine-induced immune changes in health and common diseases....

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Comment 2002; 23(5-6): 385-386 PubMed PMID: 12500157 Citation  Keywords:  Child, Preschool, Circadian Rhythm:physiology, Humans, Japan, Melatonin:analogs & derivatives, Photic Stimulation, Photoperiod, Saliva:chemistry, Sleep:physiology, Time Factors, Urine:chemistry,.   

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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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Journal Article 2019; 39(7): 501-514 PubMed PMID: 30860682 Citation  Keywords:  Biomarkers:blood, Dietary Supplements:adverse effects, Double-Blind Method, Female, Ferritins:blood, Folic Acid:blood, Glycated Hemoglobin A, Homocysteine:blood, Humans, Iron:blood, Male, Prospective Studies, Sex Factors, Time Factors, Vitamin B 12:blood,.   

OBJECTIVES: Pregnancy is a period in life with a high demand of micronutrients. A prophylactic supplementation of folic acid to reduce the risk of neurological malformations in the newborn is common practice. The array of essential micronutrients during pregnancy includes neurotropic vitamins (Vitamin B6, B12 and folic acid), minerals like iron, and trace elements like zinc. As the serum level of most micronutritients is actively regulated by the organism, a prophylactic broad supplementation with a mild, but effective supplementation typically does not pose any risk for exaggerated serum levels, therefore prophylactic intake may be prefered to blood screening and specific interventions. METHODS: To investigate the ingredients' bioavailability of the complex vitamin-mineral-trace element composition LaVita® we recruited healthy volunteers for six months and observed the changes of pregnancy relevant parameters by means of laboratory measures. The study design was prospective, double blind, placebo controlled, and included a "male group control". We determined baseline parameters of folate, vitamin B6 and vitamin B12, iron, zinc, homocysteine and Hb-alpha-1c. After three and six months of daily intake of the study substance the blood tests were repeated and compared to the baseline levels. RESULTS: The regular intake resulted in an increase of the supplemented substances' serum levels. The metabolic parameter homocysteine decreased significantly, Hb-alpha-1c was slightly lowered. CONCLUSION: The regular intake filled up the respective storage compartments and reservoirs in the tissues, and improved the metabolic status. Female participants tended to benefit more than male. We conclude that the composition is safe, and warrants optimized micronutrient supply during pregnancy or postnatal breastfeeding....

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