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Objective. Modified levels of pro- (caspase3, Bax) and anti-apoptotic (Bcl-2) regulatory proteins have been detected in certain brain areas of schizophrenic patients indicating a possible dysregulation of apoptosis. In the present study, effects of antipsychotics, haloperidol (HAL) and olanzapine (OLA), on the gene expression of caspase3 (casp3), Bax and Bcl-2 were studied in vitro in mouse hippocampal mHippoE-2 cell line and in vivo in the hippocampus of MK-801 animal schizophrenia model with the aim to provide evidence that antipsychotics may affect the activity of apoptosis-related markers. Methods. mHippoE-2 cells were incubated with MK-801 (20 µM), HAL (10 µM), and OLA (10 µM) alone or combined, MK-801+HAL/OLA, for 24, 48, and 72 h. Male Sprague Dawley rats were injected with saline or MK-801 (0.5 mg/kg) for 6 days and since the 7th day, they were treated with vehicle (VEH), HAL (1 mg/kg) or OLA (2 mg/kg) for the next 7 days. The casp3, Bax and Bcl-2 gene expression in mHippoE-2 cells and rat hippocampus was measured by RT-PCR. Results. In mHippoE-2 cells, casp3 gene expression was increased by MK-801 and OLA treatments alone for 48 h, HAL treatment alone for 24 and 72 h, and co-treatment with MK-801+OLA for 24 and 72 h compared to controls. HAL and OLA suppressed the stimulatory effect of MK-801 on casp3 mRNA levels in cells after 48 h of incubation. Bax mRNA levels in mHippoE-2 cells were decreased after HAL treatment for 24 and 48 h, and also after co-treatment with MK-801+HAL for 72 h. In vivo, MK-801 decreased mRNA levels of both pro-apoptotic markers, casp3 and Bax, in hippocampus of VEH-treated rats and Bax mRNA levels in hippocampus of HAL-treated animals. OLA reversed the inhibitory effect of MK-801 on casp3 expression in the VEH-treated animals. Neither MK-801 nor antipsychotics induced changes in the gene expression of anti-apoptotic marker Bcl-2 in mHippoE-2 cells as well as hippocampus of rats. Conclusions. The results of the present study demonstrate that antipsychotics, HAL and OLA, may affect mRNA levels of pro-apoptotic markers in hippocampal cells in vitro, but not in vivo. The obtained data do not clearly support the assumed potentiating role of MK-801 in inducing apoptosis in specific brain areas and a possible protective role of antipsychotics against induction of apoptosis. The obtained data may contribute to a deeper insight into the neurodevelopmental changes connected with schizophrenia.
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Antipsicóticos , Ratas , Masculino , Ratones , Animales , Antipsicóticos/farmacología , Haloperidol/farmacología , Olanzapina/farmacología , Caspasa 3/farmacología , Maleato de Dizocilpina/farmacología , Proteína X Asociada a bcl-2/genética , Benzodiazepinas/farmacología , Ratas Sprague-Dawley , Apoptosis , HipocampoRESUMEN
Accumulated data indicate that inflammation affecting brain structures participates in the development of cancer-related cachexia. However, the mechanisms responsible for the induction and progression of cancer-related neuroinflammation are still not fully understood. Therefore, we studied the time-course of neuroinflammation in selected brain structures and cachexia development in tumor-bearing rats. After tumor cells inoculation, specifically on the 7th, 14th, 21st, and 28th day of tumor growth, we assessed the presence of cancer-associated cachexia in rats. Changes in gene expression of inflammatory factors were studied in selected regions of the hypothalamus, brain stem, and circumventricular organs. We showed that the initial stages of cancer growth (7th and 14th day after tumor cells inoculation), are not associated with cachexia, or increased expression of inflammatory molecules in the brain. Even when we did not detect cachexia in tumor-bearing rats by the 21st day of the experiment, the inflammatory brain reaction had already started, as we found elevated levels of interleukin 1 beta, interleukin 6, tumor necrosis factor alpha, and glial fibrillary acidic protein mRNA levels in the nucleus of the solitary tract. Furthermore, we found increased interleukin 1 beta expression in the locus coeruleus and higher allograft inflammatory factor 1 expression in the vascular organ of lamina terminalis. Ultimately, the most pronounced manifestations of tumor growth were present on the 28th day post-inoculation of tumor cells. In these animals, we detected cancer-related cachexia and significant increases in interleukin 1 beta expression in all brain areas studied. We also observed significantly decreased expression of the glial cell activation markers allograft inflammatory factor 1 and glial fibrillary acidic protein in most brain areas of cachectic rats. In addition, we showed increased expression of cluster of differentiation 163 and cyclooxygenase 2 mRNA in the hypothalamic paraventricular nucleus, A1/C1 neurons, and area postrema of cachectic rats. Our data indicate that cancer-related cachexia is associated with complex neuroinflammatory changes in the brain. These changes can be found in both hypothalamic as well as extrahypothalamic structures, while their extent and character depend on the stage of tumor growth.
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Caquexia , Fibrosarcoma , Ratas , Animales , Ratas Wistar , Caquexia/metabolismo , Interleucina-1beta/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Enfermedades Neuroinflamatorias , Encéfalo/metabolismo , Fibrosarcoma/metabolismo , Inflamación/metabolismo , ARN MensajeroRESUMEN
Aberrant neurogenesis in the subventricular zone (SVZ) and hippocampus (HIP) contributes to schizophrenia pathogenesis. Haloperidol (HAL) and olanzapine (OLA), commonly prescribed antipsychotics for schizophrenia treatment, affect neurogenesis too. The effect of HAL and OLA on an mHippoE-2 cell line was studied in vitro where we measured the cell number and projection length. In vivo, we studied the gene expression of DCX, Sox2, BDNF, and NeuN in the SVZ and HIP in an MK-801-induced animal schizophrenia model. Cells were incubated with HAL, OLA, and MK-801 for 24, 48, and 72 h. Animals were injected for 6 days with saline or MK801 (0.5 mg/kg), and from the 7th day with either vehicle HAL (1 mg/kg) or OLA (2 mg/kg), for the next 7 days. In vitro, HAL and OLA dose/time-dependently suppressed cells' proliferation and shortened their projection length. HAL/OLA co-treatment with MK-801 for 24 h reversed HAL's/OLA's inhibitory effect. In vivo, HAL and OLA suppressed DCX and NeuN genes' expression in the HIP and SVZ. MK-801 decreased DCX and NeuN genes' expression in the HIP and OLA prevented this effect. The data suggest that subchronic HAL/OLA treatment can inhibit DCX and NeuN expression. In an MK-801 schizophrenia model, OLA reversed the MK-801 inhibitory effect on DCX and NeuN and HAL reversed the effect on DCX expression; however, only in the HIP.
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Antipsicóticos , Esquizofrenia , Animales , Antipsicóticos/uso terapéutico , Benzodiazepinas , Proliferación Celular , Modelos Animales de Enfermedad , Maleato de Dizocilpina/farmacología , Maleato de Dizocilpina/uso terapéutico , Haloperidol/farmacología , Haloperidol/uso terapéutico , Hipocampo , Olanzapina/farmacología , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/genéticaRESUMEN
CRH system integrates responses to stress challenges, whereas antipsychotics may impinge on this process. Effect of haloperidol (HAL) and aripiprazole (ARI) on chronic mild stress (CMS) induced neurobehavioral and CRH/CRHR1 system changes was studied in functionally interconnected rat brain areas including prefrontal cortex (PFC), bed nucleus of the stria terminalis (BNST), hypothalamic paraventricular nucleus (PVN), hippocampus (HIP), and amygdala (AMY). Animals were exposed to CMS for 3-weeks and since the 7th day of CMS injected with vehicle (VEH), HAL (1 mg/kg) or ARI (10 mg/kg) for 4-weeks. Expression levels of CRH, CRHR1, and c-fos genes and anxiety-like and anhedonia behavioural patterns were evaluated. CMS in VEH animals suppressed CRH gene expression in the PFC and BNST, c-fos expression in all areas, except HIP, and increased CRHR1 gene expression in the HIP. Antipsychotics decreased CRH gene expression in all areas, except HIP and by CMS elevated CRHR1 expression in the HIP (ARI also in AMY). CMS and antipsychotics decreased the sucrose preference. Aripiprazole prevented CRH expression decrease in the BNST and sucrose preference induced by CMS. Haloperidol increased time spent in the EPM open arms. These data indicate that HAL and ARI selectively influenced behavioural parameters and CRH/CRHR1 gene expression levels in CMS animals.
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Aripiprazol/farmacología , Conducta Animal/efectos de los fármacos , Hormona Liberadora de Corticotropina/efectos de los fármacos , Haloperidol/farmacología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Animales , Antipsicóticos/farmacología , Ansiedad/inducido químicamente , Ansiedad/tratamiento farmacológico , Hormona Liberadora de Corticotropina/metabolismo , Hormona Liberadora de Corticotropina/farmacología , Haloperidol/metabolismo , Masculino , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/metabolismoRESUMEN
Objective. Changes in the brain derived neurotrophic factor (BDNF) and glucocorticoid receptor (GR) expression in the prefrontal cortex (PFC) and hippocampus (HIP) are associated with psychiatric diseases and stress response. Chronic mild stress (CMS) may alter BDNF as well as GR levels in both the PFC and the HIP. The aim of the present study was to find out whether chronic treatment with a typical antipsychotic haloperidol (HAL) and an atypical antipsychotic aripiprazole (ARI) may modify the CMS effect on the BDNF and GR expression in the above-mentioned structures. Methods. The rats were exposed to CMS for 3 weeks and from the 7th day of CMS injected with vehicle (VEH), HAL (1 mg/kg) or ARI (10 mg/kg) for 4 weeks. BDNF and GR mRNA levels were established in the PFC and the HIP by Real Time PCR, whereas, PFC and HIP samples were obtained by punching them from 500 µm thick frozen sections. C-Fos immunoreactivity was analyzed in the PFC and the HIP on 30 µm thick paraformaldehyde fixed sections. Weight gain and corticosterone (CORT) levels were also measured. Results. The CMS and HAL suppressed the BDNF and GR mRNA levels in the PFC. In the HIP, CMS elevated BDNF mRNA levels that were suppressed by HAL and ARI treatments. The CMS decreased the c-Fos immunoreactivity in the PFC in both HAL- and ARI-treated animals. In the HIP, HAL increased the c-Fos immunoreactivity that was again diminished in animals exposed to CMS. Stressed animals gained markedly less weight until the 7th day of CMS, however, later their weight gain did not differ from the unstressed ones or was even higher in CMS+HAL group. Un-stressed HAL and ARI animals gained less weight than the VEH ones. Neither CMS nor HAL/ARI affected the plasma CORT levels. Conclusion. The present data indicate that HAL and ARI in the doses 1 mg/kg or 10 mg/kg, respectively, does not modify the effect of the CMS preconditioning on the BDNF and GR mRNA levels in the PFC or the HIP. However, HAL seems to modify the CMS effect on the HIP activation.
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Antipsicóticos , Haloperidol , Animales , Antipsicóticos/farmacología , Aripiprazol/farmacología , Factor Neurotrófico Derivado del Encéfalo/genética , Hipocampo , Corteza Prefrontal , Ratas , Receptores de Glucocorticoides/genéticaRESUMEN
The sympathetic nervous system participates in the development and progression of several cancer types and this effect is mediated mainly via ß-adrenergic signaling. However, the potential of ß-adrenergic signaling blockade to prevent cancer development after exposure to carcinogens has not been investigated, yet. Therefore, in our study, we determined the effect of the ß-blocker propranolol on the development and progression of mammary cancer induced in female rats by administration of the chemical carcinogen N-methyl-N-nitrosourea (MNU). The propranolol treatment (20 mg/kg body weight) started 12 days after MNU administration and lasted 10 weeks. We found that both saline and propranolol treatment significantly increased gene expression of the catecholamine-synthesizing enzyme tyrosine hydroxylase, indicating that repeated injection of saline or propranolol-induced stress in these two groups. However, compared to the vehicle-treated group, propranolol slightly delayed the development and moderately reduced the incidence of mammary carcinoma in animals. To evaluate the mechanisms mediating the effect of propranolol on the development of MNU-induced cancer, we investigated several parameters of the tumor microenvironment and found that propranolol increased gene expression of Casp3. Our data indicate that propranolol treatment that starts after exposure to carcinogens might represent a new, useful approach for preventing the development of cancer, especially in stressed individuals. However, the potential efficiency of propranolol treatment for preventing cancer development and progression in individuals exposed to carcinogens needs further investigation.
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Antagonistas Adrenérgicos beta/farmacología , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Propranolol/farmacología , Animales , Caspasa 3/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Metilnitrosourea/farmacología , Feniletanolamina N-Metiltransferasa/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos beta/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Tirosina 3-Monooxigenasa/efectos de los fármacosRESUMEN
The corticotropin-releasing hormone family of peptides is involved in regulating the neuroendocrine stress response. Also, the vagus nerve plays an important role in the transmission of immune system-related signals to brain structures, thereby orchestrating the neuroendocrine stress response. Therefore, we investigated gene expression of urocortin 2 (Ucn2) and c-fos, a markers of neuronal activity, within the hypothalamic paraventricular nucleus (PVN), a brain structure involved in neuroendocrine and neuroimmune responses, as well as in the adrenal medulla and spleen in vagotomized rats exposed to immune challenge. In addition, markers of neuroendocrine stress response activity were investigated in the adrenal medulla, spleen, and plasma. Intraperitoneal administration of lipopolysaccharide (LPS) induced a significant increase of c-fos and Ucn2 gene expression in the PVN, and adrenal medulla as well as increases of plasma corticosterone levels. In addition, LPS administration induced a significant increase in the gene expression of tyrosine hydroxylase (TH) and phenylethanolamine N-methyltransferase (PNMT) in the adrenal medulla. In the spleen, LPS administration increased gene expression of c-fos, while gene expression of TH and PNMT was significantly reduced, and gene expression of Ucn2 was not affected. Subdiaphragmatic vagotomy significantly attenuated the LPS-induced increases of gene expression of c-fos and Ucn2 in the PVN and Ucn2 in the adrenal medulla. Our data has shown that Ucn2 may be involved in regulation of the HPA axis in response to immune challenge. In addition, our findings indicate that the effect of immune challenge on gene expression of Ucn2 is mediated by vagal pathways.
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Hormona Liberadora de Corticotropina/metabolismo , Expresión Génica/efectos de los fármacos , Lipopolisacáridos/farmacología , Núcleo Hipotalámico Paraventricular/metabolismo , Urocortinas/metabolismo , Médula Suprarrenal/efectos de los fármacos , Animales , Hormona Liberadora de Corticotropina/genética , Masculino , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas Sprague-Dawley , Bazo/efectos de los fármacos , Urocortinas/genética , Vagotomía , Nervio Vago/cirugíaRESUMEN
The brain exerts complex effects on the initiation and progression of cancer in the body. However, the influence of cancer localized in peripheral tissues on the brain has been only partially described. Therefore, we investigated gene expression in brain structures that participate in transmitting viscerosensory signals, regulating autonomic functions and food intake, as well as cognition in C57Bl/6J mice with B16-F10 melanoma. In addition, we investigated the relationship between peripheral inflammation and neuroinflammation. We found increased neuronal activity in the nucleus of the solitary tract of tumor-bearing mice, whereas neuronal activity in the A1/C1 catecholaminergic cell group, parabrachial nucleus, lateral hypothalamic area, ventromedial nucleus of the hypothalamus, paraventricular nucleus of the hypothalamus, and hippocampus was decreased. In the majority of investigated brain structures, we found increased gene expression of IL-1ß, whereas gene expression of IL-6 and NF-κB was reduced or unchanged compared with controls. Melanoma-bearing mice also showed increased gene expression of tyrosine hydroxylase in the A1/C1 catecholaminergic cell group, nucleus of the solitary tract, and locus coeruleus, as well as reduced mRNA levels of hypocretin neuropeptide precursor protein in the lateral hypothalamic area, and proopiomelanocortin in the arcuate nucleus. In addition, we found reduced mRNA levels of Bcl-2, brain-derived neurotrophic factor, and doublecortin in the hippocampus. Our data indicate that skin melanoma induces complex changes in the brain, and these changes are most probably caused by cancer-related signals mediated by pro-inflammatory cytokines.
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Hipotálamo , Melanoma , Animales , Encéfalo , Cognición , Ingestión de Alimentos , Expresión Génica , Ratones , Ratones Endogámicos C57BL , SensaciónRESUMEN
Recent data indicate that peripheral, as well as hypothalamic pro-inflammatory cytokines play an important role in the development of cancer cachexia. However, there are only a few studies simultaneously investigating the expression of inflammatory molecules in both the periphery and hypothalamic structures in animal models of cancer cachexia. Therefore, using the Yoshida ascites hepatoma rat's model of cancer cachexia we investigated the gene expression of inflammatory markers in the spleen along with the paraventricular and arcuate nuclei, two hypothalamic structures that are involved in regulating energy balance. In addition, we investigated the effect of intracerebroventricular administration of PS-1145 dihydrochloride (an Ikß inhibitor) on the expression of selected inflammatory molecules in these hypothalamic nuclei and spleen. We observed significantly reduced food intake in tumor-bearing rats. Moreover, we found significantly decreased expression of IL-6 in the spleen as well as decreased NF-κB in the paraventricular nucleus of rats with Yoshida ascites hepatoma. Similarly, expression of TNF-α, IL-1ß, NF-κB, and COX-2 in the arcuate nucleus was significantly reduced in tumor-bearing rats. Administration of PS-1145 dihydrochloride reduced only the gene expression of COX-2 in the hypothalamus. Based on our findings, we suggest that the growing Yoshida ascites hepatoma decreased food intake by mechanical compression of the gut and therefore this model is not suitable for investigation of the inflammation-related mechanisms of cancer cachexia development.
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Ascitis/metabolismo , Encéfalo/metabolismo , Caquexia/metabolismo , Carcinoma Hepatocelular/metabolismo , Mediadores de Inflamación/metabolismo , Neoplasias Hepáticas Experimentales/metabolismo , Bazo/metabolismo , Animales , Ascitis/complicaciones , Ascitis/inmunología , Encéfalo/inmunología , Caquexia/etiología , Caquexia/inmunología , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/inmunología , Línea Celular Tumoral , Inflamación/etiología , Inflamación/inmunología , Inflamación/metabolismo , Neoplasias Hepáticas Experimentales/complicaciones , Neoplasias Hepáticas Experimentales/inmunología , Masculino , Ratas , Ratas Wistar , Bazo/inmunologíaRESUMEN
The mechanisms underlying stress-related modulation of immune function via urocortin 1 and urocortin 2 have been only vaguely described. Therefore, we investigated the effect of LPS injection or immobilization stress on gene expression of urocortin 1 and urocortin 2 in the rat spleen, along with the potential involvement of glucocorticoids. Our data showed: a) different regulation of urocortin 1 and urocortin 2 gene expression in the rat spleen under different stressful conditions (LPS vs. immobilization stress) and b) diverse effects of stress-induced adrenal glucocorticoids on this process. Our findings indicate a specific, rather than general regulation of splenic immune function by urocortins during stressful conditions.
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Hormona Liberadora de Corticotropina/biosíntesis , Glucocorticoides/fisiología , Bazo/metabolismo , Estrés Psicológico/metabolismo , Urocortinas/biosíntesis , Animales , Corticosterona/sangre , Hormona Liberadora de Corticotropina/genética , Expresión Génica , Masculino , Ratas , Ratas Sprague-Dawley , Estrés Psicológico/genética , Estrés Psicológico/psicología , Urocortinas/genéticaRESUMEN
The mechanisms responsible for the anti-inflammatory effects of antidepressants are only partially understood. Published data indicate that the vagal anti-inflammatory pathway could be involved in mediating this effect. Therefore, we investigated the influence of subdiaphragmatic vagotomy on the anti-inflammatory effect of fluoxetine in rats injected with lipopolysaccharide (LPS) to induce an inflammatory response. The extent of this response was determined by measurement of TNF-α, IL-1ß, and IL-6 plasma levels, along with gene expression of TNF-α, IL-1ß, and IL-6 in the spleen and selected structures of the brain. To evaluate possible central mechanisms, c-fos mRNA levels were determined in the nucleus of the solitary tract, dorsal motor nucleus of the vagus, paraventricular hypothalamic nucleus, basolateral amygdala, central nucleus of the amygdala, hippocampus, and frontal cortex. We found that pretreatment with fluoxetine substantially prevented LPS-induced increases of pro-inflammatory cytokines in plasma and gene expression in the spleen and brain in animals with an intact vagus nerve. However, in vagotomized animals, fluoxetine pretreatment only partially attenuated the LPS-induced increase in these markers of peripheral inflammation. Our data has shown that fluoxetine exerts potent anti-inflammatory effects in both the periphery and brain. Moreover, we found that the peripheral anti-inflammatory action of fluoxetine is mediated, at least partially, by activation of a vagal anti-inflammatory pathway. The role of the vagus nerve in mediating the anti-inflammatory effects of antidepressants has been marginally explored and our findings highlight its potential contribution to this mechanism of action of antidepressants.
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Antiinflamatorios/farmacología , Antidepresivos/farmacología , Fluoxetina/farmacología , Mediadores de Inflamación/metabolismo , Nervio Vago/metabolismo , Animales , Vías Eferentes/efectos de los fármacos , Vías Eferentes/metabolismo , Mediadores de Inflamación/antagonistas & inhibidores , Masculino , Ratas , Ratas Sprague-Dawley , Vagotomía/tendencias , Nervio Vago/efectos de los fármacos , Nervio Vago/cirugíaRESUMEN
Corticotropin-releasing factor is well known activator of the hypothalamic-pituitary-adrenocortical axis, that represents crucial system participating on stress response of the organism. Urocortins are members of the corticotropin-releasing factor family of peptides with proposed effects on neuroendocrine and behavioral stress response mechanisms. Urocortin 2, one of three known urocortins, is present in central and peripheral stress response system and its expression can be augmented by glucocorticoids. In the present study we have examined how glucocorticoid withdrawal affects urocortin 2 gene expression after acute immobilization in the adrenal medulla and selected brain areas in rats. We used pharmacological adrenalectomy to block synthesis of corticosterone. Our results show that the immobilization-induced rise in urocortin 2 mRNA levels in rat adrenal medulla was not inhibited by glucocorticoid withdrawal. On the other hand, observed changes in the brain indicate that the effect of stress and pharmacological adrenalectomy on urocortin 2 gene expression is site-specific. While in the paraventricular nucleus and locus coeruleus the immobilization induced rise of urocortin 2 was not inhibited by pharmacological adrenalectomy in the arcuate nucleus and central amygdala it was. Moreover, we have seen a significant depletion of urocortin 2 plasma levels after immobilization. The immobilization induced rise of urocortin 2 gene expression in rat adrenal medulla and brain areas regulating stress response pathways and preservation of its induction after adrenalectomy suggests a role of urocortin 2 in the neuroendocrine stress response of an organism. This article is protected by copyright. All rights reserved.
RESUMEN
Accumulated evidence indicates that sympathetic nerves may potentiate tumor growth, including melanoma. To elucidate possible mechanisms for this effect, we performed chemical sympathectomy by intraperitoneal (i.p.) injection of the neurotoxin 6-hydroxydopamine hydrobromide (100 mg/kg of body weight); in nine adult male C57BL/6J mice; nine control mice received i.p. vehicle (VEH). Seven days later, all mice were injected subcutaneously with 3 × 10(3) B16-F10 melanoma cells. Mice were euthanized 20 d after injection of melanoma cells, for measurement of tumor weight and expression of genes related to sympathetic signaling, apoptosis, hypoxia and angiogenesis in tumor tissue. To assess potential involvement of the hypothalamo-pituitary-adrenocortical axis in the effect of sympathectomy on melanoma growth, concentrations of plasma corticosterone and level of glucocorticoid receptor mRNA in tumor tissue were determined. We found that sympathectomy significantly attenuated melanoma growth (tumor weight 0.29 ± 0.16 g versus 1.02 ± 0.30 g in controls; p < 0.05). In tumor tissue from sympathectomized mice, we found significantly increased gene expression (measured by real-time PCR), relative to VEH-injected controls, of tyrosine hydroxylase, neuropeptide Y and glucocorticoid receptor (all p < 0.05), and alpha1, beta1 and beta3 adrenergic receptors (all p < 0.025), and factors related to apoptosis (Bcl-2 and caspase-3; p < 0.05) and hypoxia (hypoxia inducible factor 1 alpha) (p = 0.005). Plasma corticosterone concentrations were significantly elevated (p < 0.05) in these mice. Our findings indicate that sympathectomy induces complex changes in the tumor microenvironment reducing melanoma growth. Such complex changes should be considered in the prediction of responses of cancer patients to interventions affecting sympathetic signaling in tumor tissue and its environment.
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Regulación Neoplásica de la Expresión Génica , Melanoma Experimental/cirugía , Sistema Nervioso Simpático/cirugía , Animales , Apoptosis/fisiología , Caspasa 3/metabolismo , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Neuropéptido Y/metabolismo , Oxidopamina/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Simpatectomía Química , Carga Tumoral , Microambiente Tumoral , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
We have previously described the development of substantial, but reversible obesity in Wistar rats fed with palatable liquid nutrition (Fresubin). In this study, we investigated changes in serum hormone levels, glycemia, fat mass, adipocyte size, and gene expression of adipokines and inflammatory markers in adipose tissue of Wistar rats fed by Fresubin (i) for 5 months, (ii) up to 90 days of age, or (iii) after 90 days of age to characterize metabolic alterations and their reversibility in rats fed with Fresubin. An intra-peritoneal glucose tolerance test was also performed to determine levels of serum leptin, adiponectin, insulin, and C-peptide in 2- and 4-month-old animals. In addition, mesenteric and epididymal adipose tissue weight, adipocyte diameter, and gene expression of pro- and anti-inflammatory adipokines and other markers were determined at the end of the study. Chronic Fresubin intake significantly increased adipocyte diameter, reduced glucose tolerance, and increased serum leptin, adiponectin, insulin, and C-peptide levels. Moreover, gene expression of leptin, adiponectin, CD68, and nuclear factor kappa B was significantly increased in mesenteric adipose tissue of Fresubin fed rats. Monocyte chemotactic protein 1 messenger RNA (mRNA) levels increased in mesenteric adipose tissue only in the group fed Fresubin during the entire experiment. In epididymal adipose tissue, fatty acid binding protein 4 mRNA levels were significantly increased in rats fed by Fresubin during adulthood. In conclusion, chronic Fresubin intake induced complex metabolic alterations in Wistar rats characteristic of metabolic syndrome. However, transition of rats from Fresubin to standard diet reversed these alterations (AU)
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Animales , Masculino , Obesidad/etiología , Adiposidad , Grasa Abdominal/metabolismo , Regulación del Desarrollo de la Expresión Génica , Alimentos Formulados/efectos adversos , Proteínas en la Dieta/efectos adversos , Hiperglucemia , Hiperinsulinismo , Ratas Wistar , Intolerancia a la Glucosa , Proteínas de Unión a Ácidos Grasos , Quimiocina CCL2 , Tamaño de la Célula , Distribución AleatoriaRESUMEN
We have previously described the development of substantial, but reversible obesity in Wistar rats fed with palatable liquid nutrition (Fresubin). In this study, we investigated changes in serum hormone levels, glycemia, fat mass, adipocyte size, and gene expression of adipokines and inflammatory markers in adipose tissue of Wistar rats fed by Fresubin (i) for 5 months, (ii) up to 90 days of age, or (iii) after 90 days of age to characterize metabolic alterations and their reversibility in rats fed with Fresubin. An intra-peritoneal glucose tolerance test was also performed to determine levels of serum leptin, adiponectin, insulin, and C-peptide in 2- and 4-month-old animals. In addition, mesenteric and epididymal adipose tissue weight, adipocyte diameter, and gene expression of pro- and anti-inflammatory adipokines and other markers were determined at the end of the study. Chronic Fresubin intake significantly increased adipocyte diameter, reduced glucose tolerance, and increased serum leptin, adiponectin, insulin, and C-peptide levels. Moreover, gene expression of leptin, adiponectin, CD68, and nuclear factor kappa B was significantly increased in mesenteric adipose tissue of Fresubin fed rats. Monocyte chemotactic protein 1 messenger RNA (mRNA) levels increased in mesenteric adipose tissue only in the group fed Fresubin during the entire experiment. In epididymal adipose tissue, fatty acid binding protein 4 mRNA levels were significantly increased in rats fed by Fresubin during adulthood. In conclusion, chronic Fresubin intake induced complex metabolic alterations in Wistar rats characteristic of metabolic syndrome. However, transition of rats from Fresubin to standard diet reversed these alterations.
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Grasa Abdominal/metabolismo , Adiposidad , Proteínas en la Dieta/efectos adversos , Alimentos Formulados/efectos adversos , Regulación del Desarrollo de la Expresión Génica , Síndrome Metabólico/etiología , Obesidad/etiología , Grasa Abdominal/inmunología , Grasa Abdominal/patología , Adipoquinas/genética , Adipoquinas/metabolismo , Factores de Edad , Animales , Bebidas/efectos adversos , Biomarcadores/metabolismo , Tamaño de la Célula , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Progresión de la Enfermedad , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Intolerancia a la Glucosa/etiología , Intolerancia a la Glucosa/prevención & control , Hiperglucemia/etiología , Hiperglucemia/prevención & control , Hiperinsulinismo/etiología , Hiperinsulinismo/prevención & control , Masculino , Obesidad/metabolismo , Obesidad/patología , Obesidad/fisiopatología , Distribución Aleatoria , Ratas WistarRESUMEN
Neuroendocrine stress response is regulated by several feedback loops. Since it has been suggested that afferent vagal pathways contribute to these feedback loops, we examined the effect of surgical subdiaphragmatic vagotomy on both baseline and stress-induced increases in plasma epinephrine, norepinephrine, and corticosterone levels in vagotomized and sham-operated Sprague Dawley rats. On either the 3rd or 14th day following vagotomy, the animals were exposed to acute immobilization stress and blood from the jugular vein was collected both before and during stress exposure. We found that vagotomy significantly enhanced immobilization-induced increases of plasma epinephrine, norepinephrine, and corticosterone levels on the 3rd day following surgery. However, on the 14th day following surgery, vagotomy enhanced only increase of plasma epinephrine levels in stressed rats. Our data indicate that afferent pathways of the vagus nerve are involved in negative feedback regulation of epinephrine secretion from the adrenal medulla during stressful conditions. We hypothesize that this feedback mechanism might be mediated by the binding of circulating epinephrine on ß2-adrenergic receptors localized on sensory endings of the vagus nerve.
Asunto(s)
Epinefrina/sangre , Estrés Psicológico/fisiopatología , Nervio Vago/fisiopatología , Animales , Peso Corporal/fisiología , Corticosterona/sangre , Retroalimentación Fisiológica , Sistema Hipotálamo-Hipofisario/fisiopatología , Masculino , Norepinefrina/sangre , Sistema Hipófiso-Suprarrenal/fisiopatología , Distribución Aleatoria , Ratas Sprague-Dawley , Restricción Física , Factores de Tiempo , Vagotomía/métodosRESUMEN
While the parasympathetic nervous system appears to be involved in the regulation of tumor progression, its exact role is still unclear. Therefore, using a rat BP6-TU2 fibrosarcoma tumor model, we investigated the effect of (1) reduction of vagal activity produced by subdiaphragmatic vagotomy; and (2) enhancement of vagal activity produced by continuous delivery of electric impulses to the cervical part of the vagus nerve on tumor development and survival of tumor-bearing rats. We also evaluated the expression of cholinergic receptors within in vitro cultivated BP6-TU2 cells. Interestingly, we found that both, vagal stimulation and subdiaphragmatic vagotomy slightly reduced tumor incidence. However, survival of tumor-bearing rats was not affected by any of the experimental approaches. Additionally, we detected mRNA expression of the α1, α2, α5, α7, and α10 subunits of nicotinic receptors and the M1, M3, M4, and M5 subtypes of muscarinic receptors within in vitro cultivated BP6-TU2 cells. Our data indicate that the role of the vagus nerve in modulation of fibrosarcoma development is ambiguous and uncertain and requires further investigation.
Asunto(s)
Fibrosarcoma/patología , Nervio Vago/fisiopatología , Animales , Línea Celular Tumoral , Estimulación Eléctrica , Fibrosarcoma/mortalidad , Fibrosarcoma/fisiopatología , Masculino , ARN Mensajero/metabolismo , Ratas Wistar , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Tasa de Supervivencia , VagotomíaRESUMEN
The involvement of the nonclassical renin-angiotensin system (RAS) in the adrenomedullary response to stress is unclear. Therefore, we examined basal and immobilization stress (IMO)-triggered changes in gene expression of the classical and nonclassical RAS receptors in the rat adrenal medulla, specifically the angiotensin II type 2 (AT2) and type 4 (AT4) receptors, (pro)renin receptor [(P)RR], and Mas receptor (MasR). All RAS receptors were identified, with AT2 receptor mRNA levels being the most abundant, followed by the (P)RR, AT1A receptor, AT4 receptor, and MasR. Following a single IMO, AT2 and AT4 receptor mRNA levels decreased by 90 and 50%, respectively. Their mRNA levels were also transiently decreased by repeated IMO. MasR mRNA levels displayed a 75% transient decrease as well. Conversely, (P)RR mRNA levels were increased by 50% following single or repeated IMO. Because of its abundance, the function of the (P)RR was explored in PC-12 cells. Prorenin activation of the (P)RR increased phosphorylation of extracellular signal-regulated kinase 1/2 and tyrosine hydroxylase at Ser(31), likely increasing its enzymatic activity and catecholamine biosynthesis. Together, the broad and dynamic changes in gene expression of the nonclassical RAS receptors implicate their role in the intricate response of the adrenomedullary catecholaminergic system to stress.
Asunto(s)
Médula Suprarrenal/metabolismo , Inmovilización , Sistema Renina-Angiotensina , Estrés Psicológico/metabolismo , Médula Suprarrenal/fisiopatología , Animales , Catecolaminas/biosíntesis , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Masculino , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Células PC12 , Fosforilación , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , ATPasas de Translocación de Protón/genética , ATPasas de Translocación de Protón/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 2/genética , Receptor de Angiotensina Tipo 2/metabolismo , Receptores de Angiotensina/genética , Receptores de Angiotensina/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Sistema Renina-Angiotensina/genética , Serina , Estrés Psicológico/genética , Estrés Psicológico/fisiopatología , Factores de Tiempo , Tirosina 3-Monooxigenasa/metabolismo , ATPasas de Translocación de Protón VacuolaresRESUMEN
The sympathetic nervous system regulates many immune functions and modulates the anti-tumor immune defense response, too. Therefore, we studied the effect of 6-hydroxydopamine induced sympathectomy on selected hematological parameters and inflammatory markers in rats with Yoshida AH130 ascites hepatoma. We found that chemically sympathectomized tumor-bearing rats had significantly increased neutrophil-to-lymphocyte ratio, leukocyte-to-lymphocyte ratio, and plasma levels of tumor necrosis factor alpha. Although our findings showed that sympathetic denervation in tumor-bearing rats led to increased neutrophil-to-lymphocyte ratio, that is an indicator of the disease progression, we found no significant changes in tumor growth and survival of sympathectomized tumor-bearing rats.
Asunto(s)
Linfocitos/fisiología , Neutrófilos/fisiología , Sarcoma de Yoshida/inmunología , Sarcoma de Yoshida/patología , Simpatectomía Química , Animales , Peso Corporal/efectos de los fármacos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Eritrocitos , Estimación de Kaplan-Meier , Leucocitos/efectos de los fármacos , Leucocitos/fisiología , Linfocitos/efectos de los fármacos , Masculino , Neutrófilos/efectos de los fármacos , Norepinefrina/metabolismo , Oxidopamina/farmacología , Ratas , Ratas Wistar , Sarcoma de Yoshida/mortalidad , Bazo/metabolismo , Simpaticolíticos/farmacología , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangreRESUMEN
BACKGROUND: Adaptation to stress is critical for survival. The adrenal medulla, the major source of epinephrine, plays an important role in the development of the hyperadenergic state and increased risk for stress associated disorders, such as hypertension and myocardial infarction. The transcription factor Egr1 plays a central role in acute and repeated stress, however the complexity of the response suggests that other transcription factor pathways might be playing equally important roles during acute and repeated stress. Therefore, we sought to discover such factors by applying a systems approach. RESULTS: Using microarrays and network analysis we show here for the first time that the transcription factor signal transducer and activator of transcription 3 (Stat3) gene is activated in acute stress whereas the prolactin releasing hormone (Prlh11) and chromogranin B (Chgb) genes are induced in repeated immobilization stress and that along with Egr1 may be critical mediators of the stress response. CONCLUSIONS: Our results suggest possible involvement of Stat3 and Prlh1/Chgb up-regulation in the transition from short to repeated stress activation.