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Namazi M. The cellular immunodeficiency associated with post-traumatic stress disorder may be the result of sympathetic overactivity and be correctable by beta-2-blockers. Neuro Endocrinol Lett. 2003 Dec; 24(6): 469-473
OBJECTIVES: Detection of the antiestrogenic effect of melatonin on various breast cancer cell lines and its dependence of the differential expression of estrogen receptors (ERalpha and ERbeta) and melatonin receptors (mt1 and RZRalpha).
SETTING AND DESIGN: Dose-response curves of estradiol were determined in 6 different breast cancer cell lines using a colorimetric proliferation assay in the absence or presence of various melatonin concentrations.
METHODS: In order to detect the minor growth inhibitory effect of melatonin, a simple yet novel approach was employed: instead of incubating cells at single estradiol-concentrations at increasing melatonin levels, breast cancer cells were grown in microwell-plates for 4 days at increasing concentrations of estradiol (10(-12)M - 10(-10)M) in the absence or presence of melatonin (10(-9)M - 10(-8)M). Cell number was determined using Alamar blue and colorimetry. RT-PCR was performed for the expression of ERalpha, ERbeta, RZRalpha and mt1.
RESULTS: Melatonin at concentrations of 10(-9)M and 5 x 10(-9)M shifted the dose-response curves of estradiol to higher concentrations. Responsiveness to melatonin depended on expression of ERalpha but not on ERbeta. mRNA of ERbeta was not detectable in the breast cancer cell lines used. Only small amounts of mt1 transcripts were detectable in MCF-7 cells of one source. In MCF-7 cells transfected with the mt1 gene and in an ovarian cancer cell line mt1 was expressed at significant levels. RZRalpha was expressed in all tested cell lines at different amounts.
CONCLUSION: The growth of all ERalpha-positive breast cancer cell lines can be inhibited by melatonin. The effect in most cell lines is weak yet clearly reproducible. RZRalpha clearly contributes to the growth inhibitory effect of melatonin....
Girgert R, Bartsch C, Hill S, Kreienberg R, Hanf V. Tracking the elusive antiestrogenic effect of melatonin: a new methodological approach. Neuro Endocrinol Lett. 2003 Dec; 24(6): 440-444
: Both corticotropin releasing hormone (CRH) and serotonin (5-HT) participate in the stress response and are known to modulate cytokine release by human immune cells. Extracellular 5-HT concentrations at or above the serum values have negative immunoregulatory effects by inhibiting the production of interferon-gamma (IFNgamma), a pro-inflammatory cytokine produced by Th-1-like lymphocytes, whereas 5-HT has no significant effects on the production of interleukin-10 (IL-10), an anti-inflammatory cytokine. In one study, CRH significantly decreases IFNgamma production by cultured human peripheral blood immunocytes, whereas in other studies CRH increases the production of cytokines, such as IL-1, IL-2 and IL-6. The aims of the present study were to examine i) the effects of CRH, 10-9 M, 10(-8) M and 10(-7) M, on the stimulated production of IFNgamma, IL-10 and tumor necrosis factor-alpha (TNFalpha) by human whole blood; and ii) whether CRH, 10(-9) M, 10(-8) M and 10(-7) M, may antagonize some of the negative immunoregulatory effects of 5-HT, 1.5 microg/mL or 15 microg/mL. We found that CRH, 10(-9) M, 10(-8) M and 10(-7) M, had no significant effects either on the stimulated production of IFNgamma, IL-10 or TNFalpha or on the IFNg/IL-10 production ratio, which reflects the pro-inflammatory capacity of the culture. 5-HT, 1,5 microg/dL and 15 microg/dL, significantly suppressed the production of IFNgamma and TNFalpha and the IFNg/IL-10 production ratio. CRH, 10(-7) M, significantly reversed the 5-HT (1.5 microg/mL and 15 microg/mL)-induced suppression of IFNg production. CRH at all concentrations significantly blocked the 5-HT (1.5 microg/mL and 15 microg/mL)-induced suppression of TNFalpha production. The results suggest that CRH has no significant direct effects on the production of IFNgamma, IL-10 and TNFalpha, but antagonizes the negative immunoregulatory effects of 5-HT on the production of IFNgamma and TNFalpha and on the IFNgamma/IL-10 production ratio....
Maes M, Kenis G, Kubera M. In humans, corticotropin releasing hormone antagonizes some of the negative immunoregulatory effects of serotonin. Neuro Endocrinol Lett. 2003 Dec; 24(6): 420-424
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....
Matalka K. Neuroendocrine and cytokines-induced responses to minutes, hours, and days of mental stress. Neuro Endocrinol Lett. 2003 Oct; 24(5): 283-292
OBJECTIVES: The immunocytochemical study of the localization of hormones in thymic cells has been performed to clarify possible correlations of their expression with proliferative activity of thymocytes.
METHODS: We used commercial antibodies to serotonin, melatonin, somatostatin, glucagon, gastrin, beta-endorphin and histamine, and ABP or BSP kits for visualization of reaction. Computer image analysis was used to find correlations between hormone production and proliferative activity of thymocytes.
RESULTS: Different subpopulations of thymocytes are able to produce hormones: precursors of T-lymphocytes (CD4-CD8-) contain serotonin and melatonin, immature cortical cells (CD4+CD8+) produce only serotonin, mature medullar cells (CD4+CD8-) show immunoreactivity to serotonin, melatonin, beta-endorphin and histamine. The expression of serotonin, somatostatin and gastrin is localized in thymic epithelial cells, formatting Gassal's bodies. Proliferative activity of thymocytes depends from the expression of serotonin and somatostatin in thymic cells.
CONCLUSION: The data received testify the expression of different hormones in human thymic cells and showing by this fact high endocrine activity of thymus. The presence of correlations between hormonal expression and cell proliferative activity could be considered as the bright illustration of important role of neuroimmunoendocrine mechanisms in the regulation of local thymic homeostasis....
Kvetnoy I, Polyakova V, Trofimov A, Yuzhakov V, Yarilin A, Kurilets E, Mikhina L, Sharova N, Nikonova M. Hormonal function and proliferative activity of thymic cells in humans: immunocytochemical correlations. Neuro Endocrinol Lett. 2003 Aug; 24(3-4): 263-268
OBJECTIVES AND DESIGN: Researchers of the St. Petersburg Institute of Bioregulation and Gerontology of the North-Western Branch of the Russian Academy of Medical Sciences and the Institute of Gerontology of the Ukrainian Academy of Medical Sciences (Kiev) clinically assessed the geroprotective effects of thymic (Thymalin) and pineal (Epithalamin) peptide bioregulators in 266 elderly and older persons during 6-8 years. The bioregulators were applied for the first 2-3 years of observation.
RESULTS: The obtained results convincingly showed the ability of the bioregulators to normalize the basic functions of the human organism, i.e. to improve the indices of cardiovascular, endocrine, immune and nervous systems, homeostasis and metabolism. Homeostasis restoration was accompanied by a 2.0-2.4-fold decrease in acute respiratory disease incidence, reduced incidence of the clinical manifestations of ischemic heart disease, hypertension disease, deforming osteoarthrosis and osteoporosis as compared to the control. Such a significant improvement in the health state of the peptide-treated patients correlated with decreased mortality rate during observation: 2.0-2.1-fold in the Thymalin-treated group; 1.6-1.8-fold in the Epithalamin-treated group; 2.5-fold in the patients treated with Thymalin plus Epithalamin as compared to the control. A separate group of patients was treated with Thymalin in combination with Epithalamin annually for 6 years and their mortality rate decreased 4.1 times as compared to the control.
CONCLUSIONS: The obtained data confirmed the high geroprotective efficacy of Thymalin and Epithalamin and the expediency of their application in medicine and social care for health maintenance and age-related pathology prevention in persons over 60 to prolong their active longevity....
Khavinson V, Morozov V. Peptides of pineal gland and thymus prolong human life. Neuro Endocrinol Lett. 2003 Aug; 24(3-4): 233-240
: We demonstrate the presence in leech hemolymph of high levels of a peptide recognized by antiserum directed against bovine chromacin. The purification of the chromacin-like peptide was carried out by an acidic extraction, followed by solid phase and high pressure gel permeation chromatography and reversed-phase HPLC purification. Its sequence (GDFELPSIADPQATFESQRGPSAQQVDK) was established by a combination of techniques, including automated Edman degradation, MALDI-TOF measurement and DOT immunobinding assays with anti-chromogranin A. Mass spectrometry measurement revealed a m/z 3177Da, revealing the fact that the molecule is phosphorylated. ELISA titrations performed at each step of the purification revealed a major increase in the level of the peptide (ca. 125 nmol/microl of coelomic fluid) 15 min after LPS exposure. The increase in chromacin-like peptide levels is both time and concentration dependent. The level of this peptide decreased significantly 4 hours after LPS exposure. This report is the first discovery of a chromogranin derived like peptide in invertebrates....
Salzet M, Stefano G. Chromacin-like peptide in leeches. Neuro Endocrinol Lett. 2003 Aug; 24(3-4): 227-232
OBJECTIVE: Cocaine- and amphetamine-regulated transcript (CART) is widely expressed in the rat brain, especially in the hypothalamic nuclei and in the anterior pituitary. The aim of this study was to evaluate the effects of CART on pituitary hormone release in pituitary cell culture.
MATERIAL AND METHODS: The pituitary hormone release from pituitary cell culture after CART administration was investigated. Concentrations of LH, FSH, PRL, TSH and GH were measured with RIA methods.
RESULTS: CART in all doses (1 nMol, 10 nMol, 100 nMol) stimulated prolactin (PRL) release and inhibited TSH release. CART administration caused a dose dependent decrease in LH release. CART did not change GH release from cultured pituitary cells.
CONCLUSION: CART may affect directly pituitary hormones release in the cell culture....
Baranowska B, Woliñska-Witort E, Chmielowska M, Martyñska L, Baranowska-Bik A. Direct effects of cocaine-amphetamine-regulated transcript (CART) on pituitary hormone release in pituitary cell culture. Neuro Endocrinol Lett. 2003 Aug; 24(3-4): 224-226