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Journal Article 2002; 23(4): 315-320 PubMed PMID: 12195233 Citation  Keywords:  Animals, Genes, Immediate-Early:physiology, Hypothalamus:cytology, Male, Neurons:physiology, Physical Stimulation, Proto-Oncogene Proteins c-fos:genetics, Rats, Rats, Sprague-Dawley, Skin:radiation effects,.   

OBJECTIVES: The purpose of this study was to determine: 1) The spatial pattern of c-fos gene expression in rat hypothalamic neurons after exposure to NMS and 2) The expression of c-fos gene after combined exposure to NMS and EHF irradiation of the rat skin.

METHODS: The experiments were performed on 28 male adult Sprague-Dawley rats. After rats were subjected to noxious mechanical stimulation (NMS) or its combination with EHF irradiation of the skin, cells in various hypothalamic structures were analyzed to determine theirs effects on c-fos gene expression, an accepted marker of the activation of neurons. C-Fos-like protein was revealed by an indirect immunoperoxidase method.

RESULTS: This study revealed that NMS stimulates c-fos gene expression in the anterior hypothalamic nucleus (AHN), dorsomedial hypothalamic nucleus (DMH), ventromedial hypothalamic nucleus (VMH), and lateral hypothalamic area (LHA) by 157, 101, 199 and 115% respectively compared to control animals. Combined exposure to NMS and EHF irradiation directed at the skin in the region of the St36 acupuncture point projection site (left side) results in a decrease of the number of neurons that are activated in the AHN, DMH, VMH, and LHA by 33.6, 13.2, 31.0 and 32.9% respectively compared to the number of neurons activated by exposure to NMS by itself. EHF exposure of the skin of rats not subjected to NMS differentially effects the number of c-Fos positive cells expressed in hypothalamic structures: a decrease of 39.7% was observed in the number of activated neurons in the central part of LHA (level 28) compared to sham-irradiated animals, while an increase of 80.95% was noted in the number of c-Fos positive cells in the DMH compared to sham-irradiated animals.

CONCLUSIONS: The spatial pattern and degree of activation of c-fos gene expression has been shown in cells of the hypothalamus of rats after exposure to NMS by itself and after NMS combined with EHF irradiation of the skin. The "stress" reaction of cells in specific hypothalamic structures has been shown to be decreased after EHF exposure of the skin....

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Journal Article 2002; 23(Suppl 1): 55-60 PubMed PMID: 12019353 Citation  Keywords:  Animals, Blotting, Southern, Blotting, Western, Cell Membrane:metabolism, Cell Nucleus:metabolism, Colonic Neoplasms:genetics, Gene Expression Regulation, Neoplastic:genetics, Male, Mice, Neoplasm Transplantation, Nuclear Receptor Subfamily 1, Group F, Me.   

OBJECTIVES: There are some data suggesting that melatonin exerts oncostatic action through membrane as well as nuclear receptors. In previous studies we demonstrated the antiproliferative and proapoptotic action of melatonin on transplantable murine Colon 38 adenocarcinoma cells. Therefore, the aim of the present study was to determine whether the membrane melatonin receptors MT(1) and MT(2) as well as the nuclear receptor RZR/ROR alpha are expressed in Colon 38 cells.

MATERIAL AND METHODS: Adult male B6D2F1 mice were used in this experiment. The induction of tumor was conducted by subcutaneous injection of 0.2 mL of a 33% suspension of Colon 38 cancer cells into axillary region. Expression of mRNA encoding MT(1) and MT(2) melatonin membrane receptors was studied by RT-PCR analysis, and expression of ROR alpha(1) nuclear receptor protein was studied by Western blot analysis.

RESULTS: The expression of mRNA encoding both MT(1) and MT(2) melatonin receptors was demonstrated in Colon 38 cancer cells. Moreover, immunodetection revealed the expression of MT(1) and ROR alpha(1) proteins in these cells.

CONCLUSIONS: Our studies on Colon 38 adenocarcinoma cells support the concept that both membrane and nuclear receptors are involved in the oncostatic action of melatonin....

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Journal Article 2002; 23(2): 95-100 PubMed PMID: 12011792 Citation  Keywords:  Adult, Aged, Analgesics, Opioid:pharmacology, Base Sequence, Down-Regulation:drug effects, Endothelium, Vascular:drug effects, Estrogen Receptor beta, Female, Gene Expression:drug effects, Humans, In Vitro Techniques, Male, Middle Aged, Molecular Sequence.   

UNLABELLED: Human vascular endothelial cells express the estrogen receptor-beta (ER-beta), which can be modulated by the opiate alkaloid morphine.

OBJECTIVES: To determine if morphine is capable of down regulating the ER-beta receptor in a similar fashion as the mu opiate receptor since they are both coupled to constitutive nitric oxide synthase derived nitric oxide release.

METHODS AND RESULTS: Endothelial cells obtain from human vascular tissues (saphenous vein, atria and primary saphenous vein cells) were treated with 1 uM morphine plus or minus the mu opiate receptor antagonist naloxone or CTOP (10 uM) for 24 h at 37 degrees C. Total RNA was isolated from treated and untreated primary endothelial cells, and specific primers and a probe were used to determine the ER-beta gene expression by real-time RT-PCR. Cells treated with morphine exhibited a down-regulation of ER-beta, whereas naloxone and CTOP were able to partially block the morphine effect. In addition, the 266 bp fragment generated by RT-PCR using the same primers as in the real-time PCR was sequenced and revealed a 100% sequence identity as the authentic ER-beta gene sequence.

CONCLUSIONS: These results indicate that ER-beta is expressed in human vascular endothelial cells, and morphine appears to regulate this receptor in a similar fashion as the mu opiate receptor....

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Journal Article 2001; 22(6): 461-466 PubMed PMID: 11781545 Citation  Keywords:  Adrenal Glands:chemistry, Animals, Brain-Derived Neurotrophic Factor:analysis, Chromaffin Cells:physiology, Colitis:immunology, Gene Expression:immunology, Glial Cell Line-Derived Neurotrophic Factor, Male, Nerve Growth Factor:analysis, Nerve Growth Facto.   

OBJECTIVES: Neurotrophins and GDNF have been recently recognized as important local regulators of inflammatory processes of the gut.

RESULTS: We now demonstrate that experimental TNBS-colitis is associated with the increased expression of neurotrophins and GDNF in the adrenal glands. In histological sections of the adrenals from untreated control animals, faint immunolabeling for BDNF, NT-3 and NGF was detectable in the adrenal cortex, with some additional labeling for NGF over the adrenal medulla, whereas GDNF immunolabeling was confined to the adrenal medulla. Induction of TNBS-colitis markedly increased NGF, BDNF, and NT-3 expression within the adrenal cortex after 8 h. NGF declined to basal levels after 7 days. In case of BDNF and NT-3 basal expression levels were reached after 14 days. GDNF expression was robustly upregulated in the adrenal medulla 8 h after induction of colitis and stayed elevated for up to 14 days.

CONCLUSION: Together these observations suggest that neurotrophins and GDNF might act as local modulators of components of the HPA-axis during peripheral inflammation....

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Journal Article 2001; 22(6): 441-447 PubMed PMID: 11781542 Citation  Keywords:  Age Factors, Animals, Antioxidants:pharmacology, Female, Gene Expression Regulation, Neoplastic:drug effects, Mammary Neoplasms, Experimental:drug therapy, Melatonin:pharmacology, Mice, Mice, Transgenic, Photoperiod, RNA, Messenger:analysis, Receptor, Erb.   

OBJECTIVES AND DESIGN: The effect and the mechanism of light regimen and melatonin on the development of mammary tumors in HER2/neu transgenic mice were investigated. Female HER-2/neu mice starting from the age of 2 months were kept under standard light/dark regimen (LD) or constant light illumination (LL) and a part of each group was given melatonin (20 mg/l) during the night time.

RESULTS: The exposure to LL failed to change the incidence of spontaneous mammary adenocarcinoma development, the size of mammary tumors, as well as the incidence and size of lung metastases. However, the number of tumors per mouse was significantly increased in the LL group as compared to the LD group. The number of mice bearing 4 and more tumors was higher in the LL group than in the LD group, whereas the number of mice bearing 1 to 3 tumors was lower in the LL group in comparison with the LD group. Melatonin decreased the incidence and size of mammary adenocarcinomas, and the incidence of lung metastases in the LD group but not in the LL group. The mean number of tumors per mouse was not changed by melatonin treatment in both light regimens. The number of mice bearing 4 and more tumors was reduced by melatonin more significantly in the LL group than in LD group. Melatonin treatment resulted in a 2.5-fold reduction in the expression of HER-2/neu mRNA in mammary tumors from HER-2 /neu transgenic mice.

CONCLUSION: The data demonstrate the influence of the LD light regiment and melatonin treatment in the development of spontaneous mammary tumors in HER-2/neu mice suggesting a melatonin-dependent modulation of HER-2/neu gene expression in mammary adenocarcinoma....

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Journal Article 2001; 22(6): 435-440 PubMed PMID: 11781541 Citation  Keywords:  Animals, Gene Expression:physiology, Gonadotropin-Releasing Hormone:metabolism, Luteinizing Hormone:genetics, Pituitary Gland, Anterior:physiology,.   

: Detailed studies have been focused on the mechanisms by which the rat alpha and LHbeta genes are differentially regulated by GnRH and indicate that differential sensitivity to the second messenger exists in a physiological context. Differential signaling from the GnRH receptor may be a mechanism for preferential regulation of luteinizing hormone subunit gene transcription; however which of these genes are specifically regulated by PKC or calcium and how GnRH pulsatility could preferentially activate individual pathways of second messengers within gonadotrope cells remain unclear. Several transcription factors that have profound effects on basal and/or GnRH-stimulated LHbeta gene promoter activity have been identified: SF-1, Egr-1, Sp-1. A model explaining possible interactions among them in mediating GnRH responsiveness of the LHbeta gene has been proposed: Sp1, SF-1 and Egr-1 form a tripartite GnRH response element which is sensitive to the spacing changes between the upstream Sp1 binding sites and the downstream SF-1/Egr-1 binding elements and SF-1 plays a critical role in integrating the effects of Sp1 and Egr-1. GnRH responsive element located on LHbeta gene promoter in position between -495 to -342 has been identified. At 3'-end of the promoter three Sp-1 binding sites have been identified: position -416, sequence: GGGGGCTGGG and two sites almost completely overlapping, position -403, sequence; GGGGCGGCGCCCA while at the 5'region of the promoter one Sp-1 binding site exists: position -450, sequence: ACCACACCCATTTTTGG. The 5'Sp1 site overlaps a CArG box (at -443 to -434, sequence: CCATTTTTGG) which seems to be essential in LHbeta gene sensitivity for pulsatile GnRH stimulation....

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Journal Article 2019; 39(7): 525-531 PubMed PMID: 30860684 Citation  Keywords:  5-Aminolevulinate Synthetase:biosynthesis, Animals, Arachidonate 15-Lipoxygenase:biosynthesis, Female, Gene Expression:drug effects, Growth Hormone:pharmacology, Hippocampus:metabolism, Hypophysectomy, Insulin-Like Growth Factor I:metabolism, Rats, Weight.   

OBJECTIVE: Growth hormone (GH) increases insulin-like growth factor I (IGF-I) production and both hormones affect hippocampal plasticity. We have previously shown that Hbb and Alas2 in the rat hippocampus were robustly regulated by GH-infusions for six days, whereas other transcripts were weakly affected. Here, we explored the effects of prolonged GH administration on transcripts linked to neuroprotection and investigated whether serum IGF-I administration may exert similar effects. DESIGN: Hypophysectomised female rats were infused with GH or IGF-I for 19 days. Hbb, Alas2 and seven additional GH- and IGF-I-related transcripts were quantified by Q-RT-PCR in rat hippocampus. RESULTS: Three transcripts, Hbb, Alas2, and Alox15 were increased by both GH and IGF-I administration. The other transcripts were marginally affected. CONCLUSION: The 19-day GH-infusion induced similar effects as those reported after 6-day GH treatment, with the addition of the regulation of transcript Alox15. IGF-I induced altered gene expression in relation to its effect on weight gain. This study underlines that there is an entity of transcripts involved in neuroprotection and vascular tone that is regulated by both systemic GH and IGF-I. For other transcripts, the longer duration of this study did not significantly enhance the marginal effects of GH administration seen previously....

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