RESUMO
OBJECTIVE: The number of teeth has been shown to affect mortality. However, it is unclear why the number of teeth is associated with mortality. We focused on the number of teeth and malnutrition and examined whether these differences affect 3-year all-cause mortality among very elderly individuals. METHODS: This analysis was conducted using data from the Tokyo Oldest Old Survey on Total Health study. Altogether 513 participants ≥85 years were categorized based on remaining teeth (0, 1-7, 8-18, ≥19). All-cause mortality was determined by calculating the cumulative 3-year survival rate according to the remaining number of teeth and the presence/absence of malnutrition. Further, hazard ratios (HRs) were analyzed using Cox regression analyses. RESULTS: No difference was observed according to the number of teeth (p = 0.638), but the presence/absence of malnutrition was significantly associated with mortality (p < 0.001). Malnutrition was independently associated with higher HRs, even after adjusting for confounding factors associated with mortality. (HR: 2.315, 95% CI: 1.431-3.746). Additionally, adjusting for the number of teeth, HR remained significant (HR: 2.365, 95% CI: 1.449-3.853). CONCLUSION: In the very elderly, malnutrition-but not the number of teeth-was independently associated with 3-year all-cause mortality after adjusting for various health issues.
Assuntos
Desnutrição , Saúde Bucal , Idoso , Idoso de 80 Anos ou mais , Humanos , Desnutrição/complicações , Modelos de Riscos Proporcionais , Inquéritos e Questionários , Taxa de Sobrevida , Expectativa de Vida , MortalidadeRESUMO
Allograft inflammatory factor-1 (AIF-1) is expressed in microglia. Unilateral common carotid artery occlusion (UCCAO) was conducted to elucidate mechanisms that regulate AIF-1 expression in C57BL/6 male mice. Immunohistochemical reactivity of microglia against anti-AIF-1 antibody was increased significantly in the brain of this model. The increased AIF-1 production was further confirmed by ELISA using brain homogenate. Real-time PCR demonstrated that the increased AIF-1 production was regulated at the transcriptional level. Serum AIF-1 levels were further examined by ELISA and marked increase was observed on Day 1 of UCCAO. To examine the influence of AIF-1, immunohistochemical staining was performed and revealed that the immunoreactivity against anti-Iba-1 antibody was significantly increased in various organs. Among them, the accumulation of Iba-1+ cells were observed prominently in the spleen. Intraperitoneal injection of minocycline, a potent microglia inhibitor, reduced the number of Iba-1+ cells suggesting microglia activation-dependent accumulation. Based on these results, AIF-1 expression was further examined in the murine microglia cell line MG6. AIF-1 mRNA expression and secretion were up-regulated when the cells were cultured under hypoxic condition. Importantly, stimulation of the cells with recombinant AIF-1 induced the expression of AIF-1 mRNA. These results may suggest that increased AIF-1 production by microglia in cerebral ischemia regulate the AIF-1 mRNA expression at least in part by an autocrine manner.
Assuntos
Encéfalo , Microglia , Masculino , Camundongos , Animais , Microglia/metabolismo , Camundongos Endogâmicos C57BL , Encéfalo/metabolismo , RNA Mensageiro/metabolismo , AloenxertosRESUMO
In modern society, stress caused by relationships and emotions is one of the greatest social problems. Similar to humans, domestic and captive animals live under various stresses. Several stresses have been associated with skin disorders, such as atopic dermatitis, but there is a lack of reliable and objective indicators for the characterization of this association. This study aimed to define the changes in fatty acid composition and amino acid concentration in the skin following repeated restraint stress in ICR mice. Mice subjected to 30 min of daily restraint stress for 8 days showed changes in the composition of saturated fatty acids, such as an increase in palmitic acid content, which are the substrates of Δ-9 desaturase. Conversely, unsaturated fatty acids decreased with stress treatment, which appeared to be a result of these fatty acids being the substrate of Δ-6 desaturase. Changes in fatty acid composition after stress treatment may be one of the factors that cause skin inflammation. The water-retention capacity may have been lowered by stress treatment because histidine and leucine, which are natural moisturizing factors, were significantly decreased. The collagen content in the skin gradually decreased after repeated stress treatment. Our results indicate that repeated restraint stress may impact skin health through changes in both the fatty acid composition and amino acid concentration in mice.
Assuntos
Ácidos Graxos , Restrição Física , Aminoácidos , Animais , Ácidos Graxos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Restrição Física/veterináriaRESUMO
BACKGROUND/AIM: Acid-electrolyzed functional water (FW) is an efficient bactericide and gargling with FW might be an effective method of oral care. We investigated the possible use of FW as a mouth wash by an in vitro study. MATERIALS AND METHODS: The bactericidal effect of FW against different species of bacteria (Staphylococcus aureus, Streptococcus pneumonia, Pseudomonas aeruginosa, and Candida albicans) was evaluated using the numbers of colony-forming units (CFU). The experiment was conducted using PBS, LISTERINE, and ConCool F (undiluted, and the optimal concentration indicated). To investigate the bactericidal mechanism of FW, the activity of superoxide dismutase (SOD), an indicator of oxidative action, was measured in S. aureus. FW was diluted with purified water to concentrations of 10, 30, 50, and 70%. The numbers of CFU were measured for each concentration. XTT assays were performed using HSC-3 and HeLa cells, to examine the viability of the cells following treatment with FW. The same experiment was conducted with PBS, LISTERINE, and undiluted ConCool F. RESULTS: No bacteria treated with FW formed colonies. SOD activity peaked at a 50% concentration of FW and was more than twice that of the control. A significant decrease in the number of CFU was observed following 50% treatment. Since the peaks of the SOD activity and the starting concentrations of the bactericidal effects coincided, the bactericidal effect of FW might be related to its oxidative effects. Bacteria treated with FW had the same survival rate as the other mouth washes. CONCLUSION: FW might be clinically applicable as a mouth wash.
Assuntos
Antissépticos Bucais , Água , Antibacterianos/farmacologia , Bactérias , Células HeLa , Humanos , Antissépticos Bucais/farmacologia , Staphylococcus aureus , Superóxido Dismutase/farmacologia , Água/farmacologiaRESUMO
Conjugated linoleic acid (CLA) has anti-obesity effects, but induces fatty liver in mice. The present study investigated whether co-administration of arachidonic acid (ARA) attenuates fat accumulation in the mouse liver induced by CLA. Male mice (8 weeks old) were given diets with either no addition of dietary fat (control), 3 % linoleic acid (LA), 3 % CLA, 3 % CLA+1 % ARA, or 3 % CLA+2 % ARA for 4 weeks. The perirenal fat weight in ARA-treated groups decreased similarly as with CLA alone, when compared to control or LA. Plasma TAG concentration was significantly higher in the CLA group than in either CLA+ARA group, while plasma cholesterol and NEFA concentrations did not vary among the groups. In contrast to visceral fat, liver weight was significantly higher in the CLA group than in the control or LA groups, and the effects of CLA were attenuated by ARA. TAG and cholesterol were markedly accumulated in the liver with dietary CLA, whereas co-administration with ARA, at either concentration, suppressed CLA-induced lipid accumulation. Liver PGE(2) was enhanced by a combination of CLA and ARA when compared with CLA alone, but PGE(1) level was not significantly different among groups. In conclusion, fatty liver induced by CLA was attenuated by co-administration with ARA, furthermore, a combination of these fatty acids maintained the anti-obese effect of CLA.
Assuntos
Ácido Araquidônico/uso terapêutico , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/prevenção & controle , Ácidos Linoleicos Conjugados/efeitos adversos , Animais , Ácido Araquidônico/metabolismo , Colesterol/sangue , Dinoprostona/metabolismo , Ácidos Graxos não Esterificados/sangue , Fígado Gorduroso/metabolismo , Ácidos Linoleicos Conjugados/uso terapêutico , Masculino , Camundongos , Triglicerídeos/sangueRESUMO
Conjugated linoleic acid (CLA) has a role of biogenic regulation through modifying prostaglandin production. However, its effects on related metabolites of arachidonate remain unclear. Therefore, the effects of CLA on brain endocannabinoid content as well as its analogs were investigated. Mice (3-week-old), provided with diets containing 3% linoleic acid or 3% CLA for 4 weeks, were sacrificed and lipids were extracted from their cerebral cortex and hypothalamus. The amounts of N-arachidonoyl-ethanolamide, 2-arachidonoyl-glycerol (2-AG), oleoyl-ethanolamide and palmitoyl-ethanolamide were determined quantitatively by LC-MS. The 2-AG level in the cerebral cortex was significantly decreased by CLA treatment, but the other compounds were unaffected in the cerebral cortex and hypothalamus. The present study indicated that dietary CLA site-selectively decreases 2-AG in the cerebral cortex.
Assuntos
Moduladores de Receptores de Canabinoides/metabolismo , Córtex Cerebral/metabolismo , Endocanabinoides , Hipotálamo/metabolismo , Ácido Linoleico/farmacologia , Ácidos Linoleicos Conjugados/farmacologia , Administração Oral , Animais , Ácidos Araquidônicos/metabolismo , Córtex Cerebral/efeitos dos fármacos , Glicerídeos/metabolismo , Hipotálamo/efeitos dos fármacos , Ácidos Linoleicos Conjugados/administração & dosagem , CamundongosRESUMO
Elastic fibers in the dermis play an important role in skin elasticity. The desmosine crosslinking structure constructed of lysyl oxidase (LOX) in elastic fibers contributes to elasticity, while elastic fibers are primarily degraded by one of the matrix metalloproteinases (MMPs), MMP-12. We investigated the gender differences and diurnal variation of these enzymes. Gender-based differences in LOX mRNA expression were detected, and were significantly lower in females. In contrast, higher MMP-12 mRNA expression was observed in the light period, suggesting that elastic fibers might be degraded in the light rather than the dark period.
Assuntos
Regulação Enzimológica da Expressão Gênica , Metaloproteinase 12 da Matriz/genética , Proteína-Lisina 6-Oxidase/genética , Pele/metabolismo , Animais , Ritmo Circadiano/genética , Feminino , Masculino , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Caracteres SexuaisRESUMO
The purpose of the present study was to investigate whether intracerebroventricular (ICV) injection of neuropeptide Y (NPY) affects heat production (HP), body temperature, and plasma concentrations of metabolic fuels in chicks. ICV injection of NPY (0, 188 or 375 pmol) did not affect HP, but significantly lowered respiratory quotient as well as the rectal temperature. These data suggest that the energy sources for HP were modified by NPY in the body. This idea was confirmed by subsequent experiments in which ICV injection of NPY significantly reduced plasma glucose and triacylglycerol concentrations but increased non-esterified fatty acid concentrations. The effect of NPY on the utilization of metabolic fuels was not associated changes in plasma catecholamine and corticosterone concentrations. In summary, the present study demonstrated that central NPY modifies peripheral carbohydrate and lipid metabolism in chicks.
Assuntos
Carboidratos/química , Neuropeptídeo Y/administração & dosagem , Animais , Glicemia/metabolismo , Temperatura Corporal , Galinhas , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Ácidos Graxos/metabolismo , Temperatura Alta , Injeções Intraventriculares/métodos , Metabolismo dos Lipídeos , Masculino , Fatores de Tempo , Triglicerídeos/metabolismoRESUMO
Thyrotropin-releasing hormone (TRH) is a hypothalamic signal in the hypothalamic-pituitary-thyroid (HPT) axis, and is well known as a hyperthermic hormone in the brain of chicks. The thermogenetic effect leads to the hypothesis that central TRH increases heat production (HP) in chicks. The purpose of the present study was to clarify whether central TRH affects HP of neonatal chicks, and if such an effect is mediated by corticotropin-releasing factor (CRF) since the thermogenetic effect of TRH is mediated by CRF. Intracerebroventricular (ICV) injection of TRH (14 and 55 nmol) dose-dependently increased oxygen consumption, carbon dioxide production and HP, and a similar effect was also observed with CRF (2.1 and 21 pmol). The TRH-induced increase in HP could not be attenuated by astressin, a CRF receptor antagonist, while the effect of CRF was completely diminished by astressin. The present study demonstrates that central TRH increases HP in chicks but the effect was not related to CRF.
Assuntos
Encéfalo/metabolismo , Hormônio Liberador da Corticotropina/fisiologia , Termogênese/efeitos dos fármacos , Hormônio Liberador de Tireotropina/farmacologia , Animais , Animais Recém-Nascidos , Dióxido de Carbono/sangue , Galinhas , Injeções Intraventriculares , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Tri-Iodotironina/farmacologiaRESUMO
The present study investigated whether centrally administered phosphatidylserine (PS) could modify the behavior of chicks under isolation-induced stress. Isolation stress-induced vocalization and spontaneous activity for 10 min, which were attenuated by intracerebroventricular (i.c.v.) injection of PS. The effect of PS was compared with other phospholipids or L-serine, a constituent of PS. Phosphatidylcholine (PC) had no effect on these behavior, but phosphatidylethanolamine (PE) significantly increased vocalizations and spontaneous activity compared with PS. L-Serine similarly decreased isolation-induced vocalizations and spontaneous activity. To clarify the mechanism by which central PS attenuates isolation-induced stress behavior, the contribution of the acetylcholine (ACh) receptor (AChR) was also investigated. PS was co-injected i.c.v. with the muscarinic AChR (M-AChR) antagonist scopolamine or the nicotinic AChR (N-AChR) antagonist hexamethonium. The suppression of vocalizations and spontaneous activity by PS was partially attenuated by scopolamine, but not hexamethonium. These findings indicate that isolation-induced stress behavior are attenuated by PS, acting partially through the M-AChR.
Assuntos
Encéfalo/efeitos dos fármacos , Galinhas/fisiologia , Fosfatidilserinas/farmacologia , Receptores Muscarínicos/efeitos dos fármacos , Estresse Psicológico/tratamento farmacológico , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Injeções Intraventriculares , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Antagonistas Muscarínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/metabolismo , Fosfatidilserinas/administração & dosagem , Fosfatidilserinas/metabolismo , Receptores Muscarínicos/metabolismo , Serina/administração & dosagem , Serina/metabolismo , Isolamento Social , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Fatores de Tempo , Vocalização Animal/efeitos dos fármacos , Vocalização Animal/fisiologiaRESUMO
Intracerebroventricular (ICV) injections of pituitary adenylate cyclase-activating polypeptide-38 (PACAP) and vasoactive intestinal peptide (VIP) inhibit feeding in chicks. However, the precise anorexigenic mechanisms have not been investigated, since both peptides activate the VPAC receptor in mammals. We investigated which receptor mediates the anorexigenic effects of these peptides in chicks. ICV co-injection of PACAP (6-38), a PAC1 receptor antagonist, attenuated the anorexigenic effect of PACAP but not VIP. On the other hand, ICV co-injection of [D-p-Cl-Phe6, Leu17]-VIP, a VPAC receptor antagonist, did not affect the effects of both peptides. Although these results imply that the effect of VIP was not specific, a subsequent experiment demonstrated that ICV injection of anti-chicken VIP antiserum stimulated feeding and suggested that endogenous VIP inhibits feeding in the chick brain. Collectively, the data suggest that the anorexigenic mechanism of PACAP is different from that of VIP and that an undiscovered VIP receptor may be present in the chicken brain.
Assuntos
Encéfalo/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Fármacos Gastrointestinais/farmacologia , Neuropeptídeos/farmacologia , Peptídeo Intestinal Vasoativo/farmacologia , Animais , Animais Recém-Nascidos , Comportamento Animal , Encéfalo/fisiologia , Química Encefálica , Galinhas , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Soros Imunes/farmacologia , Injeções Intraventriculares/métodos , Masculino , Fragmentos de Peptídeos/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Fatores de Tempo , Peptídeo Intestinal Vasoativo/imunologiaRESUMO
OBJECTIVE: The present study was done to clarify the mechanism by which conjugated linoleic acid (CLA) induces fatty liver in mice and to attenuate this symptom by adding other dietary fatty acids. METHODS: Mice were given CLA short (12 h) or long (4 wk) term or given CLA with linoleic acid (LA) or gamma-linolenic acid (GLA) in the long term (4 wk). Total lipids, triacylglycerol, and prostaglandin E(2) (PGE(2)) levels in the liver were determined. RESULTS: A single administration of CLA significantly increased PGE(2) levels in the liver 12 h after administration. However, long-term administration of CLA significantly decreased the liver PGE(2) level and induced fatty liver. GLA increased PGE(2) levels, and coadministration with GLA, but not with LA, prevented the CLA-induced fatty liver. CONCLUSIONS: These data suggest that CLA initially stimulates PGE(2) production followed by depletion of PGE(2) sources in the liver. The fatty liver associated with PGE(2) reduction by CLA ingestion can be attenuated by GLA in mice.
Assuntos
Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/prevenção & controle , Ácidos Linoleicos Conjugados/toxicidade , Ácido gama-Linolênico/administração & dosagem , Animais , Dinoprostona/análise , Cinética , Fígado/química , Masculino , CamundongosRESUMO
While brain development during embryogenesis has been extensively studied in precocial birds, there is no information available on altricial birds. Thus, the concentrations of the catecholamines norepinephrine (NE), epinephrine (E), and dopamine (DA), and the dopaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and 4-hydroxy-3-methoxyphenylacetic acid (HVA) were determined at several stages during the late embryonic period (E13, E14, E15, E16, E17 and E18) and the day-of-hatch (P0) in the pigeon telencephalon, cerebellum, optic lobe, and brainstem. The concentrations of all catecholamines were higher than those reported in chicken embryos. During embryogenesis, NE, E, DOPAC and HVA concentrations in the various brain parts increased throughout embryonic development until shortly before hatching at which time they decreased. DA, however, continued to increase through hatching in the brainstem, and the changes in DA concentrations varied in several brain parts. In conclusion, catecholamine concentrations in the various brain parts tended to increase with embryonic age, and the concentrations were higher than those in chickens. Furthermore, brain catcholamine metabolism changed at hatch in pigeons.
Assuntos
Encéfalo/embriologia , Catecolaminas/metabolismo , Columbidae/embriologia , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Química Encefálica , Columbidae/crescimento & desenvolvimento , Columbidae/metabolismo , Dopamina/metabolismo , Epinefrina/metabolismo , Norepinefrina/metabolismoRESUMO
This study investigated the influence of PUFA on the properties of mouse skin. Mice (3 wk old) were given free access to oils high in linoleic acid, CLA, or DHA for 4 wk. At the end of the experiment, their skins were compared by both biochemical and histological methods. No significant differences in lipid and collagen contents were detected among treatments, although the FA composition in the skin was altered depending upon the FA composition of the supplemented oils. Electron microscopy revealed that the subcutaneous tissue layers in the CLA and DHA groups were significantly thinner than that in the high linoleic acid group, whereas no differences in the thickness of dermis layers were observed among the three groups. These results suggest that skin properties in mice are readily modified by dietary FA sources within 4 wk of dietary oil supplementation.
Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Linoleicos Conjugados/farmacologia , Pele/efeitos dos fármacos , Pele/metabolismo , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Animais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/química , Ácidos Linoleicos Conjugados/administração & dosagem , Ácidos Linoleicos Conjugados/química , Camundongos , Pele/ultraestrutura , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/metabolismo , Tela Subcutânea/ultraestruturaRESUMO
Glucagon-like peptide-1 (GLP-1), derived from proglucagon, is thought to act as a negative regulator of energy homeostasis in mammals, since intracerebroventricular (ICV) injection of GLP-1 inhibits feeding behavior and enhances energy expenditure. The anorexigenic effect of GLP-1 is also observed in chicks, but whether brain GLP-1 enhances energy expenditure has not been investigated. The aim of the present study was to clarify the effect of ICV injection of GLP-1 on energy expenditure as well as metabolic changes in chicks. The injection of GLP-1 did not affect energy expenditure calculated from oxygen consumption and carbon dioxide production. On the other hand, the injection of GLP-1 significantly decreased respiratory quotient, suggesting that brain GLP-1 shifted the use of energy sources from carbohydrates to lipids. In support of this, ICV injection of GLP-1 increased plasma non-esterified fatty acid concentration while plasma glucose concentration was decreased. In conclusion, GLP-1 appears to act in the brain as a metabolic modulator rather than as a regulator of total energy expenditure in chicks.
Assuntos
Galinhas/metabolismo , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Glicemia/análise , Dióxido de Carbono/metabolismo , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Injeções Intraventriculares , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Respiração/efeitos dos fármacos , Triglicerídeos/sangueRESUMO
Alpha-melanocyte-stimulating hormone (MSH) is well known as an anorexigenic peptide in the brain of mammals. In addition to this, brain alpha-MSH enhances heat production (HP), indicating that the peptide acts as a catabolic factor in the regulation of energy metabolism. The anorexigenic effect of alpha-MSH is also observed in chicks (Gallus gallus), but no information has been available for its effect on HP. The present study was performed to examine whether intracerebroventricular (ICV) injection of alpha-MSH increases HP in chicks. The injection of alpha-MSH (10 and 100 pmol) did not affect oxygen consumption, carbon dioxide production and HP during the 1 h post-injection period. This result was supported by another result that ICV injection of alpha-MSH did not affect locomotion activity in chicks. In contrast, the respiratory quotient was significantly lowered by the ICV injection of MSH. We also found that alpha-MSH significantly increased plasma non-esterified fatty acid concentrations. In summary, brain alpha-MSH appears to exert generally catabolic effects on lipid metabolism in the chick, but does not appear to be involved in the regulation of HP.
Assuntos
Sistema Nervoso Central/metabolismo , Galinhas/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Termogênese/efeitos dos fármacos , alfa-MSH/metabolismo , Animais , Animais Recém-Nascidos , Glicemia/metabolismo , Dióxido de Carbono/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Galinhas/sangue , Ácidos Graxos não Esterificados/sangue , Injeções Intraventriculares , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Atividade Motora , Consumo de Oxigênio , Respiração , Fatores de Tempo , Triglicerídeos/sangue , alfa-MSH/administração & dosagemRESUMO
Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are the members of the glucagon superfamily and bind to common receptors while PACAP also acts via the PACAP-specific receptor, PAC1. The aim of the present study was to investigate whether intracerebroventricular (i.c.v.) injection of VIP and PACAP acts in a similar or different manner to affect body temperature and energy expenditure in the domestic chick. I.c.v. injection of VIP did not significantly affect rectal temperature, but decreased energy expenditure. On the other hand, i.c.v. injection of PACAP significantly increased both body temperature and energy expenditure. These specific actions of PACAP could be explained by an interaction with the PAC1 receptor, since they were partly, but not entirely, attenuated by PACAP (6-38), a PAC1 receptor antagonist. In addition, it was observed that central administration of both VIP and PACAP induced a reduction in respiratory quotient and increased plasma non-esterified fatty acid concentrations. This suggests that both peptides act centrally to regulate a catabolic response. In summary, brain VIP and PACAP both appear to exert generally catabolic effects on energy metabolism in the chick, but their influence on body temperature and glucose metabolism differs and their central effects do not appear to be mediated by the same receptors.
Assuntos
Galinhas/fisiologia , Metabolismo Energético/efeitos dos fármacos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/administração & dosagem , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Peptídeo Intestinal Vasoativo/administração & dosagem , Peptídeo Intestinal Vasoativo/farmacologia , Animais , Glicemia , Temperatura Corporal/efeitos dos fármacos , Dióxido de Carbono/metabolismo , Ácidos Graxos/sangue , Hipertermia Induzida , Masculino , Atividade Motora/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Triglicerídeos/sangueRESUMO
Alpha-melanocyte-stimulating hormone (alpha-MSH) is recognized as an anorexic peptide in the brain of vertebrates, but its mechanism of action has not been identified in birds. Therefore, we investigated whether the anorexic effect of alpha-MSH is mediated by corticotrophin-releasing factor (CRF) in the domestic chick. Firstly, we found that intracerebroventricular (i.c.v.) injection of alpha-MSH dose dependently increased plasma corticosterone (CORT) concentration. This effect was partly attenuated by co-injection of astressin, a CRF receptor antagonist, demonstrating that alpha-MSH stimulated CORT secretion by activating CRF neurons. The alpha-MSH-elicited CORT release was not attenuated by the injection of agouti-related protein, an endogenous melanocortin-4 (MC4) receptor antagonist, suggesting that alpha-MSH stimulated CRF neurons through MC4 receptor-independent pathways. Finally, we found that the anorexic effect of alpha-MSH was partly attenuated by astressin. The present results suggest that the anorexic effect of alpha-MSH in the chick brain is mediated in part by activation of CRF neurons.
Assuntos
Anorexia/metabolismo , Galinhas/fisiologia , Hormônio Liberador da Corticotropina/farmacologia , alfa-MSH/farmacologia , Proteína Relacionada com Agouti , Animais , Anorexia/induzido quimicamente , Corticosterona/sangue , Corticosterona/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Fragmentos de Peptídeos/farmacologia , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidoresRESUMO
The two principal endocannabinoids, N-arachidonoyl-ethanolamine (anandamide) and 2-arachidonoyl-glycerol (2-AG), are synthesized from arachidonic acid (AA) and AA is released as they are degraded. Therefore, the function of endocannabinoids is closely linked to AA, but the exact relationships have not been clarified, especially with respect to endocannabinoid metabolism. In the present study, oil rich in AA was administered (0, 100, 200 and 300 microl) orally to male mice for 7 days. Phospholipase D (PLD), fatty acid amide hydrolase (FAAH), diacyl-glycerol lipase (DAGL), monoacyl-glycerol lipase (MAGL) and cannabinoid 1 (CB1) receptor mRNA expressions were determined in the whole brain. No changes in the expression of any gene investigated were detected following AA treatment. However, it was demonstrated that the expression of the CB1 receptor was positively correlated with PLD, FAAH and DAGL expression. This suggests that expression of the CB1 receptor is closely coordinated with that of the enzymes which synthesize its ligands.
Assuntos
Encéfalo/fisiologia , Moduladores de Receptores de Canabinoides/genética , Endocanabinoides , RNA Mensageiro/genética , Receptor CB1 de Canabinoide/genética , Receptores de Canabinoides/genética , Amidoidrolases/genética , Animais , Encéfalo/enzimologia , Primers do DNA , Regulação da Expressão Gênica , Lipase Lipoproteica/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosfolipase D/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Glucagon-like peptide-1 (GLP-1) is recognized as an anorexic peptide in the brain of chicks. However, the mechanism underlying the inhibition of feeding has not been well studied. It is reported that GLP-1 activates neurons containing corticotrophin-releasing factor (CRF) in the brain of mammals. Since CRF is also an anorexic peptide, it is possible that the anorexic effect of GLP-1 is mediated by CRF in chicks. The present study was carried out to test this. First, we determined plasma corticosterone (CORT) concentrations after intracerebroventricular (ICV) injection of GLP-1 and found that this treatment increased CORT release in layer chicks. The CORT-releasing effect was partly attenuated by co-injection of astressin, a CRF receptor antagonist, demonstrating that GLP-1 stimulated CORT secretion by activation of CRF neurons. CRF neurons also appear to be involved in mediating the inhibition of food intake by GLP-1 because this effect was also partly attenuated by astressin. Furthermore, we demonstrated that the anorexic effect of GLP-1 was weaker in broiler than layer chicks. The present results suggest that the anorexic effect of GLP-1 might be mediated by CRF neurons in the chick brain and that the sensitivity of the inhibitory response to GLP-1 differs between chick strains.