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1.
Indian J Pharm Sci ; 74(3): 211-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-23440938

RESUMO

Rubus coreanus fruits have been employed as a traditional medicine for centuries in the Asia-Pacific region. Its pharmacological action differs according to the different extraction methods utilized and the degree of fruit ripening. In this study, we determined the cellular effect of different ethanol extracts of mature and immature Rubus coreanus fruits in human hepatic cell line, HepG2 cells. The antioxidant activity, effect on superoxide dismutase activity and cholesterol biosynthesis efficiency was also evaluated. Immature Rubus coreanus extract showed higher antioxidant capability, compared with that of its mature fractions. Cellular antioxidant proteins including HO-1, Cu/Zn-superoxide dismutase and catalase were highly expressed in the presence of Rubus coreanus. Cholesterol levels in HepG2 cells treated with the water fraction of immature Rubus coreanus were significantly reduced. This antihyperlipidaemic action of Rubus coreanus is a consequence of cholesterol biosynthesis and extracellular secretion in HepG2 cells. These results indicate that among different ethanol fraction of mature and immature Rubus coreanus fruit extracts, water extract of immature fruit extract shows higher antioxidant as well as higher antihyperlipidaemic action.

2.
Immunopharmacol Immunotoxicol ; 26(1): 135-44, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15106738

RESUMO

The preventive effect of Salvia miltiorrhiza extracts (SMEs) on the progress of bone loss induced by ovariectomy (OVX) was studied in rats. We measured body weight and bone histomorphometry in sham, OVX or SMEs-administered OVX rats. From light microscopic analyses, a porous or erosive appearances were observed on the surface of trabecular bone of tibia in OVX rats, whereas those of the same bone in sham rats and in SMEs-administered rats were composed of fine particles. The trabecular bone area and trabecular thickness in OVX rats decreased by 50% from those in sham rats, these decreases were completely inhibited by administration of SMEs for 7 weeks. In this study, the mechanical strength in femur neck was significantly enhanced by the treatment of SMEs for 7 weeks. In OVX rats, free T3 was normal in all cases, whereas free T4 was significantly increased. Although there was no difference between OVX and SMEs-administered rats in T3 level, we have found significant difference between them in T4 level. These results strongly suggest that SMEs are effective in preventing the development of bone loss induced by OVX in rats.


Assuntos
Osteoporose/prevenção & controle , Ovariectomia , Extratos Vegetais/uso terapêutico , Salvia miltiorrhiza , Fosfatase Alcalina/sangue , Animais , Cálcio/sangue , Contagem de Células , Força Compressiva/efeitos dos fármacos , Feminino , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Fêmur/patologia , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoporose/sangue , Osteoporose/patologia , Fósforo/sangue , Fitoterapia , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Tiroxina/sangue , Tri-Iodotironina/sangue
3.
Am J Chin Med ; 32(6): 883-95, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15673194

RESUMO

Yuk-Hap-Tang (YHT) induces cell death in human cervical carcinoma HeLa cells. Caspase-3, -6 and -9 were markedly activated in HeLa cells treated with YHT. The preferred substrate for caspase-3 cysteine protease, PARP, was cleaved to its 85-kDa cleavage product. YHT increased the amount of the anti-apoptotic protein, Bcl-2, and the pro-apoptotic protein, Bax. Although p53 has been reported to accumulate in cancer cells in response to anticancer agents, the p53 expression level was not changed in HeLa cells treated with YHT. Manganese (Mn)-TBAP, a mitochondria-specific SOD mimetic agent and NAC/GSH (N-acetyl cysteine/ reduced glutathione) reduced the YHT-induced cytotoxicity and decreased the number of the YHT-induced apoptotic cells. Furthermore, YHT reduced the expression of Mn-SOD protein and its activity in HeLa cells. The data demonstrate that YHT induces the apoptosis of human cervical carcinoma HeLa cells by intervening Mn-SOD.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Medicina Tradicional do Leste Asiático , Extratos Vegetais/farmacologia , Superóxido Dismutase/genética , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sequestradores de Radicais Livres/metabolismo , Células HeLa , Humanos , Cinética , Coreia (Geográfico) , Fitoterapia , Superóxido Dismutase/efeitos dos fármacos
4.
Phytother Res ; 16(1): 28-32, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11807961

RESUMO

Substance P (SP) can stimulate secretion of tumour necrosis factor-alpha (TNF-alpha) from astrocytes stimulated with lipopolysaccharide (LPS). In this study, we have examined whether an aqueous extract of Sesim-Tang inhibits the secretion of TNF-alpha from primary cultures of rat astrocytes. Sesim-Tang (10-1000 microg/mL) significantly inhibited the TNF-alpha secretion by astrocytes stimulated with LPS and SP. Interleukin-1 (IL-1) has been shown to elevate TNF-alpha secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore examined whether IL-1 mediated inhibition of TNF-alpha secretion from primary astrocytes by Sesim-Tang. Treatment with Sesim-Tang (10-1000 microg/mL) of astrocytes stimulated with both LPS and SP decreased IL-1 secretion significantly. Moreover, the secretion of TNF-alpha by LPS and SP in astrocytes was progressively inhibited with increasing amounts of IL-1 neutralizing antibody. Our results suggest that Sesim-Tang may inhibit TNF-alpha secretion by inhibiting IL-1 secretion and that Sesim-Tang has an antiinflammatory activity in the central nervous system.


Assuntos
Astrócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Astrócitos/citologia , Astrócitos/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Interleucina-1/antagonistas & inibidores , Interleucina-1/metabolismo , Lipopolissacarídeos/farmacologia , Medicina Tradicional do Leste Asiático , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Ratos , Organismos Livres de Patógenos Específicos , Substância P/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
5.
Phytother Res ; 15(7): 572-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11746835

RESUMO

Elevated levels of immunoglobulin (Ig)E are associated with immediate-type allergic reactions. The effect of an aqueous extract of Siegesbeckia glabrescens (Compositae) whole plants (SGWP) on in vivo and in vitro IgE production was studied in mice. SGWP dose-dependently inhibited the active systemic anaphylaxis and serum IgE production induced by immunization with ovalbumin and Bordetella pertussis toxin absorbed to aluminium hydroxide gel. SGWP dose-dependently inhibited IL-4-dependent IgE production by lipopolysaccharide-stimulated murine whole spleen cells. In the case of U266 human IgE-bearing B cells, SGWP also showed an inhibitory effect on IgE production. These results suggest that SGWP has an anti-allergic activity by inhibiting IgE production from B cells.


Assuntos
Anafilaxia/tratamento farmacológico , Asteraceae , Linfócitos B/efeitos dos fármacos , Imunoglobulina E/biossíntese , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Anafilaxia/etiologia , Animais , Linfócitos B/imunologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos ICR , Ovalbumina , Toxina Pertussis , Extratos Vegetais/administração & dosagem , Baço/citologia , Baço/efeitos dos fármacos , Fatores de Virulência de Bordetella
6.
Immunopharmacol Immunotoxicol ; 23(2): 175-86, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11417846

RESUMO

The objective of the currently study was to determine the effect of Kunbi-Boshin-Hangam-Tang (KBH-Tang) on the production of nitric oxide (NO). Stimulation of RAW 264.7 cells with KBH-Tang after the treatment of recombinant interferon-gamma (rIFN-gamma) resulted in increased NO synthesis. KBH-Tang partially increased NO synthesis by itself. When KBH-Tang was used in combination with rIFN-gamma, there was a marked cooperative induction of NO synthesis in a dose-dependent manner. This increase in NO synthesis was reflected as increased amount of inducible NO synthase (iNOS) protein. NO production was inhibited by NG-monomethyl-L-arginine (NGMMA). Furthermore, activation of nuclear factor (NF)-kappaB was increased by KBH-Tang. These results suggest that KBH-Tang may stimulate the NO production through the activation of the NF-kappaB.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Humanos , Interferon gama/administração & dosagem , Interferon gama/farmacologia , Coreia (Geográfico) , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Proteínas Recombinantes , ômega-N-Metilarginina/farmacologia
7.
Pharmacol Res ; 43(4): 405-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11352546

RESUMO

We investigated the effect of water extract of Solanum melongena(SMWE) on immunologic and nonimmunologic stimulation-mediated anaphylactic reactions. Nonimmunologic anaphylactic reaction was induced by compound 48/80 injection. Oral administration of SMWE (1 g kg(-1)) completely inhibited compound 48/80-induced anaphylactic reaction. Immunologic anaphylactic reaction was generated by sensitizing the skin with anti-dinitrophenyl (DNP) IgE followed 48 h later with an injection of antigen. Oral administration of SMWE (0.01--1 g kg(-1)) significantly inhibited passive cutaneous anaphylactic reaction activated by anti-DNP IgE to between 83.10 +/- 1.67% and 70.17 +/- 2.17%. SMWE (0.01--1 mg ml(-1)) also inhibited histamine release activated by compound 48/80 to between 93 +/- 2.65 and 70 +/- 1.50%. Moreover, SMWE (0.01--1 mg ml(-1)) had a significant inhibitory effect on IgE-induced tumor necrosis factor (TNF)-alpha secretion from rat peritoneal mast cells. These results indicate that SMWE inhibits immunologic and nonimmunologic stimulation-mediated anaphylactic reactions and TNF-alpha secretion from mast cells.


Assuntos
Anafilaxia/tratamento farmacológico , Anafilaxia/imunologia , Fatores Biológicos/farmacologia , Fatores Biológicos/uso terapêutico , Magnoliopsida/química , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Administração Oral , Anafilaxia/induzido quimicamente , Animais , Fatores Biológicos/administração & dosagem , Dinitrofenóis/imunologia , Modelos Animais de Doenças , Histamina/metabolismo , Imunoglobulina E/imunologia , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Ratos , Fator de Necrose Tumoral alfa/metabolismo , p-Metoxi-N-metilfenetilamina/antagonistas & inibidores , p-Metoxi-N-metilfenetilamina/farmacologia
8.
Bioresour Technol ; 76(3): 253-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11198178

RESUMO

Yeast extract was produced from brewer's yeast of a beer factory by combined enzymatic treatments using endoprotease, exoprotease, 5'-phosphodiesterase, and adenosine monophosphate (AMP)-deaminase. Effects of enzyme combination, enzyme dosages and treatment sequence on the recovery of solid and protein, flavor and compositional characteristics were investigated. Exoprotease dosage strongly affected the recovery of protein and degree of hydrolysis (DH) and sensory characteristics. When the yeast cells were treated using optimal combination of endoprotease and exoprotease (0.6% Protamex and 0.6% Flavourzyme), high solid recovery (48.3-53.1%) and the best flavor profile were obtained. Among various treatment sequences using multiple enzymes, treatment with protease followed by nuclease resulted in the highest 5'-guanosine monophosphate (5'-GMP) content. The optimal concentrations of both 5'-phosphodiesterase and AMP-deaminase were found to be 0.03%. After treatments using optimal combination of enzyme, enzyme dosages and treatment sequence for four enzymes, a high solid yield of 55.1% and 5'-nucleotides content of 3.67% were obtained.


Assuntos
Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , AMP Desaminase/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Cerveja , Suplementos Nutricionais/microbiologia , Endopeptidases/metabolismo , Exopeptidases/metabolismo , Aromatizantes/química , Aromatizantes/metabolismo , Indústria de Processamento de Alimentos/métodos , Proteínas Fúngicas/análise , Proteínas Fúngicas/metabolismo , Cinética , Peso Molecular , Diester Fosfórico Hidrolases/metabolismo , Saccharomyces cerevisiae/citologia
9.
Phytother Res ; 15(1): 53-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11180524

RESUMO

The preventive effect of the herbal formulation, "Dae-Bo-Won-Chun" (DBWC), on the progress of bone loss induced by ovariectomy (OVX) was studied in rats. From light microscope analyses, porous or erosive appearances were observed on the surface of trabecular bone of tibia in ovariectomized rats, whereas those of the same bone in sham-operated rats were composed of fine particles. The trabecular bone area and trabecular thickness in ovariectomized rats decreased by 50% from those in sham-operated rats, these decreases were completely inhibited by administration of DBWC at a concentration of 10 mg/kg per day for 7 weeks. The mechanical strength of the neck of the femur was decreased by ovariectomy, and this was significantly suppressed by the administration of DBWC. Serum phosphorus, alkaline phosphatase and thyroxine levels in ovariectomized rats increased compared with those in sham-operated rats, and increases were completely inhibited by the administration of DBWC. These results strongly suggest that DBWC is effective in preventing the development of bone loss induced by ovariectomy in rats.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Osteoporose/prevenção & controle , Plantas Medicinais , Animais , Modelos Animais de Doenças , Feminino , Fêmur/efeitos dos fármacos , Ovariectomia , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos
10.
Immunopharmacol Immunotoxicol ; 22(3): 519-30, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10946829

RESUMO

Substance P (SP) can stimulate production of tumor necrosis factor-alpha (TNF-alpha) from astrocytes stimulated with lipopolysaccharide (LPS). The objective of the current study was to determine the effect of Taraxacum officinale (TO) on the production of TNF-alpha from primary cultures of rat astrocytes. TO (100 and 1000 microg/ml) significantly inhibited the TNF-alpha production by astrocytes stimulated with LPS and SP. Interleukin-1 (IL-1) has been shown to elevate TNF-alpha production from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore examined whether IL-1 mediated inhibition of TNF-alpha production from primary astrocytes by TO. Treatment of TO (100 and 1000 microg/ml) to astrocytes stimulated with both LPS and SP decreased IL-1 production significantly. Moreover, the production of TNF-alpha by LPS and SP in astrocytes was progressively inhibited with increasing amount of IL-1 neutralizing antibody. Our results suggest that TO may inhibit TNF-alpha production by inhibiting IL-1 production and that TO has an antiinflammatory activity in the central nervous system.


Assuntos
Asteraceae , Astrócitos/efeitos dos fármacos , Astrócitos/imunologia , Plantas Medicinais , Fator de Necrose Tumoral alfa/biossíntese , Animais , Células Cultivadas , Interleucina-1/biossíntese , Lipopolissacarídeos/farmacologia , Microglia/efeitos dos fármacos , Microglia/imunologia , Ratos , Substância P/farmacologia
11.
Immunopharmacol Immunotoxicol ; 22(2): 183-93, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10952025

RESUMO

Yulda-Hanso-Tang (YH-Tang) is a prescription for the Taeumin cerebral infarction (CI) patients according to Sasang constitution philosophy. Taeumin patients with CI were treated with YH-Tang during the acute stage. Clinical signs of CI disappeared markedly in about 2 weeks after oral administration of YH-Tang in all patients. The mean interleukin (IL)-2 serum levels were lower in the patients with CI than in the normal groups, whereas the mean IL-4, IL-6 and IgE levels were significantly higher in the patients. There were no significant differences in interferon-gamma (IFN-gamma) levels between the groups. Serum IFN-gamma and IL-2 levels derived from T helper (Th)1 cells elevated significantly in the patients with CI by YH-Tang administration. Significant reduced serum levels of IL-4 and IL-6 derived from Th2 cells and IgE were observed in the patients treated with YH-Tang. During the period of YH-Tang administration, there were no other adverse effects. The data indicate that YH-Tang has a good CI treatment effect, and that its action may be due to regulation of cytokine production.


Assuntos
Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/imunologia , Citocinas/biossíntese , Medicamentos de Ervas Chinesas/uso terapêutico , Citocinas/sangue , Humanos , Imunoglobulina E/sangue , Interferon gama/sangue , Interleucina-2/sangue , Interleucina-4/sangue , Interleucina-6/sangue , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia
12.
J Ethnopharmacol ; 70(2): 135-41, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10771203

RESUMO

The aqueous extract of Sinomenium acutum stem (SSAE) (0.1-1000 mg/kg) dose-dependently inhibited systemic anaphylactic reaction induced by compound 48/80 in mice. In particular, SSAE reduced compound 48/80-induced anaphylactic reaction with 50% at the dose of 1000 mg/kg. SSAE (100-1000 mg/kg) also significantly inhibited local anaphylactic reaction activated by anti-dinitrophenyl (DNP) IgE. When mice were pretreated with SSAE at a concentration ranging from 0.1 to 1000 mg/kg, the plasma histamine levels were reduced in a dose-dependent manner. SSAE (1-1000 microg/ml) dose-dependently inhibited histamine release from the rat peritoneal mast cells (RPMCs) activated by compound 48/80 or anti-DNP IgE. In addition, SSAE (0.1 microg/ml) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha (TNF-alpha) production. These results indicate that SSAE inhibits mast cell-mediated anaphylactic reactions and TNF-alpha production from mast cells.


Assuntos
Anafilaxia/prevenção & controle , Mastócitos/efeitos dos fármacos , Plantas Medicinais , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Liberação de Histamina/efeitos dos fármacos , Imunoglobulina E/imunologia , Coreia (Geográfico) , Masculino , Mastócitos/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Peritônio/citologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/biossíntese , p-Metoxi-N-metilfenetilamina/farmacologia
13.
Immunopharmacol Immunotoxicol ; 21(4): 705-15, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10584206

RESUMO

We investigated the effect of an aqueous extract of Schizonepeta tenuifolia (STAE) on mast cell-mediated immediate-type hypersensitivity. STAE inhibited systemic allergic reaction induced by compound 48/80 in rats dose-dependently. STAE also inhibited plasma histamine levels induced by compound 48/80. STAE inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. In addition, STAE does-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. However, STAE had a significant enhancing effect on anti-DNP IgE-induced tumor necrosis factor-alpha (TNF-alpha) production from RPMC. These results indicate that STAE inhibits immediate-type hypersensitivity and suggest that STAE can selectively activate the TNF-alpha production from RPMC.


Assuntos
Anafilaxia/imunologia , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Plantas Medicinais/química , Anafilaxia/tratamento farmacológico , Anafilaxia/prevenção & controle , Animais , Dinitrofenóis/imunologia , Relação Dose-Resposta Imunológica , Liberação de Histamina/efeitos dos fármacos , Imunoglobulina E/imunologia , Lamiaceae/química , Mastócitos/metabolismo , Cavidade Peritoneal/citologia , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/biossíntese , p-Metoxi-N-metilfenetilamina/antagonistas & inibidores , p-Metoxi-N-metilfenetilamina/imunologia
14.
Am J Chin Med ; 27(3-4): 377-86, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10592847

RESUMO

Shini-San has been used for treatment of allergic disease in Korea. However, its effect in experimental models remains unknown. The mast cell plays a pivotal role in initiating allergic response by secreting intracytoplasmic granular mediators such as histamine. The present report describes an inhibitory effect of Shini-San on mast cell-mediated immediate-type allergic reactions. Topical application of compound 48/80 can induce an ear swelling response in normal (WBB6F1(-)+/+) mice but not in congenic mast cell-deficient WBB6F1-W/WV mice. Shini-San inhibited concentration-dependent mast cell-dependent ear swelling response induced by compound 48/80 in normal mice. Shini-San inhibited concentration-dependent passive cutaneous anaphylaxis induced by anti-dinitrophenyl (DNP) immunoglobulin E (IgE) in rats by topical application. Shini-San also inhibited in concentration-dependent fashion the histamine release from the rat peritoneal mast cells by compound 48/80 or anti-DNP IgE. Moreover, Shini-San had a significant inhibitory effect on compound 48/80-induced systemic anaphylactic reaction. These results indicate that Shini-San inhibits immediate type allergic reactions by inhibition of mast cell degranulation in vivo and in vitro.


Assuntos
Antialérgicos/farmacologia , Hipersensibilidade Imediata/tratamento farmacológico , Mastócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Edema/induzido quimicamente , Edema/prevenção & controle , Liberação de Histamina/efeitos dos fármacos , Hipersensibilidade Imediata/imunologia , Hipersensibilidade Imediata/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Preparações Farmacêuticas , Ratos , Ratos Wistar , p-Metoxi-N-metilfenetilamina/antagonistas & inibidores , p-Metoxi-N-metilfenetilamina/farmacologia
15.
Brain Res ; 802(1-2): 75-88, 1998 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-9748512

RESUMO

Neuropeptide Y (NPY) is known to stimulate eating behavior and to be related to behavioral patterns of carbohydrate ingestion. The present report investigates this relationship further to: (1) characterize the specific NPY projection activated in different dietary paradigms; (2) understand associated changes in circulating hormones that may mediate dietary effects on NPY neurons; and (3) determine whether endogenous NPY in conditions with macronutrient diets can be linked to body fat. Male albino Sprague-Dawley rats were tested in two feeding paradigms, one in which the rats were given a choice of the macronutrients, carbohydrate, fat or protein, or the other involving a single diet varying in carbohydrate of fat content. These studies consistently demonstrated a close association between the ingestion of carbohydrate and NPY levels, specifically in the arcuate nucleus (ARC) and medial portion of the paraventricular nucleus (PVN) of the hypothalamus. In addition to revealing increased NPY activity in animals that naturally select high carbohydrate when given a choice of macronutrients, a single diet with 65% carbohydrate (10% fat), compared to a control diet with 45% carbohydrate (30% fat), significantly potentiates NPY gene expression and NPY-immunoreactivity, as determined by in situ hybridization and immunohistochemistry. A further lowering of carbohydrate to 15% has little effect on NPY. Studies of medial hypothalamic fragments in vitro also reveal enhanced NPY release from hypothalamic tissue taken from rats maintained on high-carbohydrate diet. Together with NPY, circulating corticosterone (CORT) levels are also highest in a high-carbohydrate condition and positively correlated with NPY in the ARC. An association between NPY and adiposity in these dietary conditions is indicated by significantly higher levels of NPY in the medial PVN in rats with high body fat, whether consuming a high-carbohydrate of high-fat diet. This evidence, linking NPY to carbohydrate intake and circulating CORT, suggests a role for this peptide in glucose homeostasis that is normally exhibited under conditions when carbohydrate stores are low. Disturbances in this homeostatic process, associated with hyperinsulinemia and higher levels of NPY, become evident with only a moderate rise in body fat on a high-carbohydrate as well as high-fat diet.


Assuntos
Corticosterona/sangue , Carboidratos da Dieta/farmacologia , Neuropeptídeo Y/metabolismo , Obesidade/metabolismo , Tecido Adiposo/patologia , Animais , Dieta , Gorduras na Dieta/farmacologia , Hipotálamo/metabolismo , Masculino , Neuropeptídeo Y/genética , Obesidade/etiologia , Obesidade/patologia , Núcleo Hipotalâmico Paraventricular/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
16.
Brain Res Mol Brain Res ; 25(3-4): 305-12, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7528869

RESUMO

The neuropeptide galanin (GAL), which exists in dense concentrations within the hypothalamus, has physiological actions which are neuroendocrine in nature. In light of evidence showing GAL to alter the release of the adrenal steroid, corticosterone (CORT), a possible effect of this steroid on GAL gene expression and peptide production in discrete hypothalamic and brainstem sites was investigated. Using radioimmunoassay and in situ hybridization techniques, this peptide was examined in rats that had received SHAM surgery, adrenalectomy (ADX) and ADX+CORT replacement. The results showed a clear, site-specific change in GAL in relation to circulating CORT. A loss of CORT after ADX caused a dramatic decline in GAL peptide and mRNA levels in the arcuate nucleus and peptide levels in the median eminence, with no change occurring in other hypothalamic areas. In the brainstem, a similar change was detected in the dorsal raphe nucleus but not the locus coeruleus. The GAL peptide and mRNA levels in these specific brain areas of ADX rats was restored by CORT replacement, which had no impact on GAL in other brain sites. These findings demonstrate that CORT's impact on brain GAL is highly site specific, possibly determined by local concentrations of steroid receptors.


Assuntos
Glândulas Suprarrenais/fisiologia , Corticosterona/sangue , Hipotálamo/metabolismo , Neuropeptídeos/genética , Peptídeos/genética , Adrenalectomia , Animais , Peso Corporal/fisiologia , Corticosterona/uso terapêutico , Galanina , Expressão Gênica , Hipotálamo/química , Hibridização In Situ , Masculino , Neuropeptídeos/análise , Concentração Osmolar , Peptídeos/análise , Radioimunoensaio , Ratos , Ratos Sprague-Dawley
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