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1.
Nutrients ; 15(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37432279

RESUMO

Several studies have reported the effects of the consumption of various mushroom species on the testes in animal experimental models. Mushrooms, including enokitake mushrooms (Flammulina velutipes), and vegetables contain adenosine may affect testosterone production. Here, we aimed to elucidate the effects of enokitake and its active component, adenosine, on testosterone production in primary cultures of testicular cells in vivo using mice models and in vitro. The administration of enokitake ethanolic extract increased testosterone production in the cisplatin-impaired mouse model. The direct effect of mushroom extracts on testicular cells was examined and liquid chromatography-mass spectrometry analysis confirmed that the mushroom- and vegetable-induced increase in testosterone production mainly involved adenosine. Additionally, the administration of enokitake extract or adenosine to wet floor fatigue model mice promoted testicular testosterone production and enhanced Leydig cell function through insulin-like peptide three level upregulation. Structurally related compounds, including cordycepin, showed lower bioactivity than adenosine. This study showed that the ingestion of adenosine-containing mushrooms and vegetables may effectively increase testicular testosterone production. We conclude that mushrooms with a relatively high adenosine content, such as enokitake, may be useful against aging and fatigue.


Assuntos
Agaricales , Flammulina , Animais , Camundongos , Testosterona , Adenosina , Verduras , Modelos Animais de Doenças , Fadiga
2.
Molecules ; 25(15)2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756488

RESUMO

The young leaves of green tea become lighter in color than usual when protected from sunlight by a shading net for about two weeks while growing. These leaves are called "shaded white leaf tea" or SWLT. In the eluate of SWLT, the amount of amino acids (361 mg/L) was significantly higher than that in regular tea (53.5 mg/L). Since theanine and arginine, the first and second most abundant amino acids in SWLT, have significant antistress effects, we examined the antistress effect of SWLT on humans. SWLT or placebo green tea (3 g) was eluted with room-temperature water (500 mL). Participants consumed the tea for one week prior to pharmacy practice and continued for 10 days in the practice period. The state-trait anxiety inventory, an anxiety questionnaire, tended to be scored lower in the SWLT group than the placebo, but other stress markers showed no differences. The effect of the difference in SWLT components examined with mice showed that aspartic acid and asparagine, which are abundant in SWLT, counteracted the antistress effects of theanine and arginine. Large amounts of caffeine also interfered with SWLT's antistress effect. Thus, SWLT, which is high in caffeine and amino acids, suppressed depressant behavior in mice.


Assuntos
Aminoácidos/química , Antidepressivos/uso terapêutico , Cafeína/química , Estresse Psicológico/tratamento farmacológico , Chá/química , Aminoácidos/isolamento & purificação , Amilases/metabolismo , Animais , Antidepressivos/química , Antidepressivos/isolamento & purificação , Antidepressivos/farmacologia , Arginina/isolamento & purificação , Arginina/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Cafeína/isolamento & purificação , Catequina/química , Catequina/isolamento & purificação , Feminino , Glutamatos/isolamento & purificação , Glutamatos/uso terapêutico , Humanos , Masculino , Camundongos , Efeito Placebo , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Estresse Psicológico/patologia , Chá/metabolismo , Adulto Jovem
3.
Nutrients ; 12(1)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936294

RESUMO

Chronic stress can impair the health of human brains. An important strategy that may prevent the accumulation of stress may be the consumption of functional foods. When senescence-accelerated mice prone 10 (SAMP10), a stress-sensitive strain, were loaded with stress using imposed male mouse territoriality, brain volume decreased. However, in mice that ingested theanine (6 mg/kg), the main amino acid in tea leaves, brain atrophy was suppressed, even under stress. On the other hand, brain atrophy was not clearly observed in a mouse strain that aged normally (Slc:ddY). The expression level of the transcription factor Npas4 (neuronal PAS domain protein 4), which regulates the formation and maintenance of inhibitory synapses in response to excitatory synaptic activity, decreased in the hippocampus and prefrontal cortex of stressed SAMP10 mice, but increased in mice that ingested theanine. Lipocalin 2 (Lcn2), the expression of which increased in response to stress, was significantly high in the hippocampus and prefrontal cortex of stressed SAMP10 mice, but not in mice that ingested theanine. These data suggest that Npas4 and Lcn2 are involved in the brain atrophy and stress vulnerability of SAMP10 mice, which are prevented by the consumption of theanine, causing changes in the expression of these genes.


Assuntos
Encefalopatias/prevenção & controle , Glutamatos/farmacologia , Estresse Psicológico , Chá/química , Animais , Atrofia/prevenção & controle , Glutamatos/química , Hipocampo/efeitos dos fármacos , Abrigo para Animais , Masculino , Camundongos
4.
Biol Pharm Bull ; 42(8): 1402-1408, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366875

RESUMO

Beta-cryptoxanthin (ß-CRX, (3R)-ß, ß-caroten-3-ol) is an oxygenated carotenoid and a potent antioxidant that is abundant in Satsuma mandarin orange (Citrus unshiu MARC.), which is the most popular fruit in Japan. Since our preliminary data suggested that the ingestion of ß-CRX had an anti-stress effect in female participants, the effect was evaluated in another set of female participants. The study design was a double-blind group comparison and participants (n = 23) were randomly assigned to ß-CRX-rich orange juice or placebo (ß-CRX was removed from orange juice) groups. ß-CRX or placebo juice (125 mL, after breakfast) were consumed from 1 week prior to pharmacy practice and continued for 5 d into the practice period. Salivary α-amylase activity (sAA), a marker of sympathetic nervous system activity, was significantly higher in the evening than in the morning in the placebo-group during pharmacy practice, but not in the ß-CRX-group. This result supports the anti-stress effect of ß-CRX. The dose-dependency of ß-CRX was observed in male mice that were loaded with stress. These results indicate that the ingestion of ß-CRX is helpful to reduce stress.


Assuntos
beta-Criptoxantina/farmacologia , Citrus , Sucos de Frutas e Vegetais , alfa-Amilases Salivares/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Estresse Psicológico/tratamento farmacológico , Glândulas Suprarrenais/efeitos dos fármacos , Adulto , Animais , Método Duplo-Cego , Feminino , Frutas , Humanos , Masculino , Camundongos , Estresse Psicológico/metabolismo , Adulto Jovem
5.
Heliyon ; 5(5): e01653, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31111111

RESUMO

The stress-reducing effect of matcha, a high-quality fine-powdered green tea, has recently been clarified by animal experiments and clinical trials. However, the effect of matcha added to confectioneries is not clear. One aim of this study was to evaluate the relationship between matcha components and their stress-reducing effect in mice that were loaded with territorially-based stress. Adrenal hypertrophy, a marker of stress, was significantly suppressed in stress-loaded mice that had ingested matcha components, displaying a caffeine and epigallocatechin gallate to theanine and arginine (CE/TA) ratio of 2 or less. Another aim was to evaluate, in humans, the stress-reducing effect of matcha in cookies using test-matcha (CE/TA = 1.79) or placebo-matcha (CE/TA = 10.64). Participants, who were fifth year pharmacy college students, consumed 4.5 g of matcha in three pieces of cookie daily for 15 days. Salivary α-amylase activity, a stress marker, was significantly lower in the test-matcha group than in the placebo group. These results indicate that the CE/TA ratio of tea components is a key indicator for the suppression of stress. Moreover, matcha with a CE/TA ratio of 2 or less displays a stress-reducing effect, even if it is included in confectionery products. Such products may also benefit individuals who have no habit of drinking matcha as a beverage.

6.
Nutrients ; 10(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30308973

RESUMO

Theanine, a major amino acid in green tea, exhibits a stress-reducing effect in mice and humans. Matcha, which is essentially theanine-rich powdered green tea, is abundant in caffeine. Caffeine has a strong antagonistic effect against theanine. The stress-reducing effect of matcha was examined with an animal experiment and a clinical trial. The stress-reducing effect of matcha marketed in Japan and abroad was assessed based on its composition. The stress-reducing effect of matcha in mice was evaluated as suppressed adrenal hypertrophy using territorially-based loaded stress. High contents of theanine and arginine in matcha exhibited a high stress-reducing effect. However, an effective stress-reducing outcome was only possible when the molar ratio of caffeine and epigallocatechin gallate (EGCG) to theanine and arginine was less than two. Participants (n = 39) consumed test-matcha, which was expected to have a stress-reducing effect, or placebo-matcha, where no effect was expected. Anxiety, a reaction to stress, was significantly lower in the test-matcha group than in the placebo group. To predict mental function of each matcha, both the quantity of theanine and the ratios of caffeine, EGCG, and arginine against theanine need to be verified.


Assuntos
Ansiolíticos/farmacologia , Glutamatos/farmacologia , Estresse Psicológico/terapia , Chá/química , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Arginina/farmacologia , Cafeína/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Feminino , Glutamatos/efeitos dos fármacos , Voluntários Saudáveis , Humanos , Hipertrofia , Masculino , Camundongos , Territorialidade , Adulto Jovem
7.
J Clin Biochem Nutr ; 61(3): 210-216, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29203963

RESUMO

Epidemiological and animal studies have demonstrated that ingestion of green tea enhances healthy life. However, caffeine in green tea can interfere with sleep. In this report, we examined the effect of green tea with lowered caffeine, low-caffeine green tea, on stress and sleep of the elderly. The participants (n = 10, mean age 89.3 ± 4.2 years) drank five cups/day of standard green tea for 1 week. Subsequently, they drank five cups/day of low-caffeine green tea for 2 weeks. Salivary α-amylase activity (sAA) was measured as a stress marker. Sleep stages were measured using a portable electroencephalography (n = 7, 6 female and 1 male). The level of sAA in the morning (sAAm) was significantly lower when the participants drank low-caffeine green tea than standard green tea. While the levels of sAAm were different among individuals, lower sAAm correlated with a higher quality of sleep. In those participants whose sAAm was lowered by the ingestion of low-caffeine green tea, some sleep parameters improved. Daily ingestion of low-caffeine green tea may be a beneficial tool for improving the quality of sleep of the elderly via the suppression of stress, although further research is required to fortify this hypothesis.

8.
FEBS Open Bio ; 7(11): 1784-1792, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29123986

RESUMO

Small-cell lung carcinoma releases progalanin. The released progalanin is activated via a nonclassical processing pathway, being processed into an active form of galanin (1-20) by plasmin in extracellular components. Plasmin is produced from plasminogen activators. To clarify the regulation of progalanin via plasminogen activation by urokinase and tissue-plasminogen activator (t-PA), we investigated the regulation mechanism for urokinase and t-PA expression and their effect on galanin activation. Additionally, we studied the effect of activated galanin on angiogenesis. To determine the effect of cell density, we measured the expression levels of urokinase and t-PA using real-time PCR and plasminogen/gelatin zymography in a cell culture. The urokinase expression increased under both high cell density and presence of cell membrane fractions. However, urokinase increments induced by conditioned medium were low. These results indicate that expression of plasminogen activators is regulated by cell membrane factors. We used tumor-bearing mice to clarify the expression of plasminogen activators and galanin activation. Real-time PCR showed that urokinase was substantially higher in the central parts of tumors compared to the periphery, and this was confirmed by plasminogen/gelatin zymography. To evaluate the biological effect of plasminogen activators on tumor growth, we used tranexamic acid as a plasminogen inhibitor. Tranexamic acid decreased galanin (1-20) and the hemoglobin content of tumors and suppressed tumor growth. Additionally, galanin had no effect on the hemoglobin content of tumors derived from cells lacking GALR2. These results demonstrate the regulation of urokinase expression in tumors through progalanin activation in extracellular compartments, and confirm that galanin plays a role in angiogenesis.

9.
Biochem Biophys Rep ; 9: 180-186, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28956003

RESUMO

BACKGROUND: The consumption of green tea catechins (GTCs) suppresses age-related cognitive dysfunction in mice. GTCs are composed of several catechins, of which epigallocatechin gallate (EGCG) is the most abundant, followed by epigallocatechin (EGC). Orally ingested EGCG is hydrolyzed by intestinal biota to EGC and gallic acid (GA). To understand the mechanism of action of GTCs on the brain, their permeability of the blood brain barrier (BBB) as well as their effects on cognitive function in mice and on nerve cell proliferation in vitro were examined. METHODS: The BBB permeability of EGCG, EGC and GA was examined using a BBB model kit. SAMP10, a mouse model of brain senescence, was used to test cognitive function in vivo. Human neuroblastoma SH-SY5Y cells were used to test nerve cell proliferation and differentiation. RESULTS: The in vitro BBB permeability (%, in 30 min) of EGCG, EGC and GA was 2.8±0.1, 3.4±0.3 and 6.5±0.6, respectively. The permeability of EGCG into the BBB indicates that EGCG reached the brain parenchyma even at a very low concentration. The learning ability of SAMP10 mice that ingested EGCG (20 mg/kg) was significantly higher than of mice that ingested EGC or GA. However, combined ingestion of EGC and GA showed a significant improvement comparable to EGCG. SH-SY5Y cell growth was significantly enhanced by 0.05 µM EGCG, but this effect was reduced at higher concentrations. The effect of EGC and GA was lower than that of EGCG at 0.05 µM. Co-administration of EGC and GA increased neurite length more than EGC or GA alone. CONCLUSION: Cognitive dysfunction in mice is suppressed after ingesting GTCs when a low concentration of EGCG is incorporated into the brain parenchyma via the BBB. Nerve cell proliferation/differentiation was enhanced by a low concentration of EGCG. Furthermore, the additive effect of EGC and GA suggests that EGCG sustains a preventive effect after the hydrolysis to EGC and GA.

10.
Mol Nutr Food Res ; 61(12)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28891114

RESUMO

SCOPE: To understand the mechanism by which green tea lowers the risk of dementia, focus was placed on the metabolites of epigallocatechin gallate (EGCG), the most abundant catechin in green tea. Much of orally ingested EGCG is hydrolyzed to epigallocatechin (EGC) and gallic acid. In rats, EGC is then metabolized mainly to 5-(3',5'-dihydroxyphenyl)-γ-valerolactone (EGC-M5) and its conjugated forms, which are distributed to various tissues. Therefore, we examined the permeability of these metabolites into the blood-brain barrier (BBB) and nerve cell proliferation/differentiation in vitro. METHODS AND RESULTS: The permeability of EGC-M5, glucuronide, and the sulfate of EGC-M5, pyrogallol, as well as its glucuronide into the BBB were examined using a BBB model kit. Each brain- and blood-side sample was subjected to liquid chromatography tandem-mass spectrometry analysis. BBB permeability (%, in 0.5 h) was 1.9-3.7%. In human neuroblastoma SH-SY5Y cells, neurite length was significantly prolonged by EGC-M5, and the number of neurites was increased significantly by all metabolites examined. CONCLUSION: The permeability of EGC-M5 and its conjugated forms into the BBB suggests that they reached the brain parenchyma. In addition, the ability of EGC-M5 to affect nerve cell proliferation and neuritogenesis suggests that EGC-M5 may promote neurogenesis in the brain.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Catequina/metabolismo , Lactonas/farmacocinética , Neuritos/efeitos dos fármacos , Chá/química , Catequina/análogos & derivados , Catequina/farmacocinética , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Pirogalol/farmacocinética
11.
Nutrients ; 9(7)2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28753943

RESUMO

Caffeine, one of the main components in green tea, can interfere with sleep and block the effect of theanine. Since theanine, the main amino acid in tea leaves, has significant anti-stress effects in animals and humans, we examined the effects of green tea with lowered caffeine content, i.e., low-caffeine green tea (LCGT), on stress and quality of sleep of middle-aged individuals (n = 20, mean age 51.3 ± 6.7 years) in a double-blind crossover design. Standard green tea (SGT) was used as the control. These teas (≥300 mL/day), which were eluted with room temperature water, were consumed over a period of seven days after a single washout term. The level of salivary α-amylase activity (sAA), a stress marker, was significantly lower in participants that consumed LCGT (64.7 U/mL) than in those that consumed SGT (73.9 U/mL). Sleep quality was higher in participants that consumed a larger quantity of LCGT. In addition, a self-diagnostic check for accumulated fatigue was significantly lower in those participants that consumed LCGT than SGT. These results indicate that LCGT intake can reduce stress in middle-aged individuals and improve their quality of sleep. The reduction in caffeine is suggested to be a valid reason for enhancing the anti-stress effect of green tea.


Assuntos
Cafeína/farmacologia , Sono/efeitos dos fármacos , Estresse Psicológico/prevenção & controle , Chá/química , alfa-Amilases/metabolismo , Adulto , Cafeína/análise , Catequina/administração & dosagem , Catequina/análogos & derivados , Estudos Cross-Over , Método Duplo-Cego , Feminino , Glutamatos/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade
12.
Biol Pharm Bull ; 40(6): 902-909, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28566632

RESUMO

Theanine, an amino acid in tea, has significant anti-stress effects on animals and humans. However, the effect of theanine was blocked by caffeine and gallate-type catechins, which are the main components in tea. We examined the anti-stress effect of green tea with lowered caffeine, low-caffeine green tea, on humans. The study design was a single-blind group comparison and participants (n=20) were randomly assigned to low-caffeine or placebo tea groups. These teas (≥500 mL/d), which were eluted with room temperature water, were taken from 1 week prior to pharmacy practice and continued for 10 d in the practice period. The participants ingested theanine (ca. 15 mg/d) in low-caffeine green tea. To assess the anxiety of participants, the state-trait anxiety inventory test was used before pharmacy practice. The subjective stress of students was significantly lower in the low-caffeine-group than in the placebo-group during pharmacy practice. The level of salivary α-amylase activity, a stress marker, increased significantly after daily pharmacy practice in the placebo-group but not in the low-caffeine-group. These results suggested that the ingestion of low-caffeine green tea suppressed the excessive stress response of students. This study was registered at the University Hospital Medical Information Network (ID No. UMIN14942).


Assuntos
Ansiolíticos/uso terapêutico , Cafeína/análise , Estresse Psicológico/terapia , Chá , Adulto , Aminoácidos/análise , Catequina/análogos & derivados , Catequina/análise , Feminino , Humanos , Masculino , Projetos Piloto , alfa-Amilases Salivares/análise , Método Simples-Cego , Estresse Psicológico/enzimologia , Adulto Jovem
13.
Phytomedicine ; 23(12): 1365-1374, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765356

RESUMO

BACKGROUND: Theanine, an amino acid in tea, has significant anti-stress effects on animals and humans. However, the anti-stress effects of drinking green tea have not yet been elucidated. HYPOTHESIS/PURPOSE: The present study aimed to explore anti-stress effects of green tea and roles of tea components in a mouse model of psychosocial stress. STUDY DESIGN: We examined anti-stress effects of three types of green teas, theanine-rich "Gyokuro", standard "Sencha", and Sencha with lowered caffeine (low-caffeine green tea). Furthermore, the roles of tea components such as caffeine, catechins, and other amino acids in anti-stress effects were examined. METHODS: To prepare low-caffeine green tea, plucked new tea leaves were treated with a hot-water spray. Mice were psychosocially stressed from a conflict among male mice under confrontational housing. Mice consumed each tea that was eluted with room temperature water ad libitum. As a marker for the stress response, adrenal hypertrophy was compared with mice that ingested water. RESULTS: Caffeine was significantly lowered by spraying hot-water on tea leaves. While epigallocatechin gallate (EGCG) is the main catechin in tea leaves, epigallocatechin (EGC) was mainly infused into water at room temperature. Adrenal hypertrophy was significantly suppressed in mice that ingested theanine-rich and low-caffeine green tea that were eluted with water at room temperature. Caffeine and EGCG suppressed the anti-stress effects of theanine while EGC and arginine (Arg) retained these effects. CONCLUSION: These results suggest that drinking green tea exhibits anti-stress effects, where theanine, EGC and Arg cooperatively abolish the counter-effect of caffeine and EGCG on psychosocial stress induced adrenal hypertrophy in mice.


Assuntos
Arginina/farmacologia , Cafeína/efeitos adversos , Camellia sinensis/química , Catequina/análogos & derivados , Glutamatos/uso terapêutico , Estresse Psicológico/tratamento farmacológico , Chá/química , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Animais , Cafeína/farmacologia , Catequina/farmacologia , Interações Medicamentosas , Glutamatos/farmacologia , Hipertrofia , Masculino , Camundongos , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Estresse Psicológico/patologia , Temperatura , Água
14.
Yakugaku Zasshi ; 136(9): 1255-62, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-27592828

RESUMO

Beta-cryptoxanthin [ß-CRX, (3R)-ß, ß-caroten-3-ol] is a provitamin A and a potent antioxidant that is abundant in Satsuma mandarin orange (Citrus unshiu MARC.), which is the most popular fruit in Japan. The anti-stress effect of ß-CRX on humans was evaluated in fifth-year university students during both routine daily life at the university and at pharmacy practice. The study design was a double-blind group comparison and participants (n=20; female 12, male 8) were randomly assigned to ß-CRX-rich orange juice or placebo (ß-CRX was removed from orange juice) groups. ß-CRX or placebo juice (125 mL, once a day, after breakfast) were consumed from 10 d prior to the pharmacy practice and continued for 10 d into the practice period. To assess participants' anxiety, the state-trait anxiety inventory test was carried out before the pharmacy practice. Salivary α-amylase activity (sAA) was measured as a marker of sympathetic nervous system activity. In the placebo-group, sAA in the evening (post-practice sAA) tended to be higher than sAA in the morning (pre-practice sAA) during both routine daily life at the university and during pharmacy practice. In the ß-CRX-group, the increase of post-practice sAA was suppressed in females. These results suggested that ß-CRX has an anti-stress effect, at least, in females.


Assuntos
Ansiedade/prevenção & controle , beta-Criptoxantina/administração & dosagem , beta-Criptoxantina/farmacologia , Caracteres Sexuais , Estresse Psicológico/prevenção & controle , Antioxidantes , Biomarcadores/análise , Ritmo Circadiano/fisiologia , Citrus , Método Duplo-Cego , Feminino , Sucos de Frutas e Vegetais , Humanos , Masculino , Saliva/enzimologia , alfa-Amilases/análise
15.
Sci Rep ; 5: 14579, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26417724

RESUMO

The production of melanin is regulated by α-melanocyte-stimulating hormone (α-MSH), which is produced from proopiomelanocortin (POMC). Keratinocytes release POMC along with lower levels of α-MSH and ACTH. To clarify the mechanism of melanogenesis after ultraviolet (UV)-irradiation, this study focused on the expression of POMC and POMC-derived peptides after UV-irradiation. Western blot analysis and immunoassays indicated that both POMC and α-MSH-like immunoreactivity (α-MSH-LI) increased after UV-irradiation. However, other POMC-derived products were very low. In hypophysectomized mice, α-MSH-LI increased to the same level as in control mice after UV-irradiation. Structural analysis revealed that the major α-MSH-LI product was ACTH(1-8). Furthermore, ACTH(1-8) competed with [(125)I]-α-MSH for receptor binding and increased melanin production via a melanocortin-1 receptor. These results suggested that melanin was produced through ACTH(1-8) after UV-irradiation. Trypsin-like enzymatic activity, which is responsible for POMC activation, increased after UV-irradiation and was identified as tryptase. In mast cell-deficient mice, which do not produce tryptase, α-MSH-LI levels were unchanged after UV-irradiation. The present study demonstrates the production of ACTH(1-8) from POMC by tryptase, which is a novel peptide-processing mechanism in the extracellular compartment of the skin.


Assuntos
Pavilhão Auricular , Melaninas/biossíntese , Pró-Opiomelanocortina/metabolismo , Pele/metabolismo , Pele/efeitos da radiação , Raios Ultravioleta , Hormônio Adrenocorticotrópico/química , Hormônio Adrenocorticotrópico/farmacologia , Animais , Espaço Extracelular/metabolismo , Masculino , Mastócitos/imunologia , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/química , Peptídeos/imunologia , Peptídeos/metabolismo , Ligação Proteica , Receptor Tipo 1 de Melanocortina/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , alfa-MSH/imunologia , alfa-MSH/metabolismo
16.
Biochem Biophys Res Commun ; 454(1): 89-94, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25450362

RESUMO

The senescence-accelerated mouse prone10 (SAMP10) strain, a model of aging, exhibits cognitive impairments and cerebral atrophy. We noticed that SAMP10/TaSlc mice, a SAMP10 substrain, have developed persistent glucosuria over the past few years. In the present study, we characterized SAMP10/TaSlc mice and further identified a spontaneous mutation in the Slc5a2 gene encoding sodium-glucose co-transporter (SGLT) 2. The mean concentration of urine glucose was high in SAMP10/TaSlc mice and increased further with advancing age, whereas other strains of senescence-accelerated mice, including SAMP1/SkuSlc, SAMP6/TaSlc and SAMP8/TaSlc or normal aging control SAMR1/TaSlc mice, exhibited no detectable glucose in urine. SAMP10/TaSlc mice consumed increasing amounts of food and water compared to SAMR1/TaSlc mice, suggesting the compensation of polyuria and the loss of glucose. Oral glucose tolerance tests showed decreased glucose reabsorption in the kidney of SAMP10/TaSlc mice. In addition, blood glucose levels decreased in an age-dependent fashion. The kidney was innately larger than that of control mice with no histological alterations. We examined the expression levels of glucose transporters in the kidney. Among SGLT1, SGLT2, glucose transporter (GLUT) 1 and GLUT2, we found a significant decrease only in the level of SGLT2. DNA sequencing of SGLT2 in SAMP10/TaSlc mice revealed a single nucleotide deletion of guanine at 1236, which resulted in a frameshift mutation that produced a truncated protein. We designate this strain as SAMP10/TaSlc-Slc5a2(slc) (SAMP10-ΔSglt2). Recently, SGLT2 inhibitors have been demonstrated to be effective for the treatment of patients with type 2 diabetes (T2D). SAMP10-ΔSglt2 mice may serve as a unique preclinical model to study the link between aging-related neurodegenerative disorders and T2D.


Assuntos
Envelhecimento/genética , Mutação da Fase de Leitura , Transportador 2 de Glucose-Sódio/genética , Envelhecimento/metabolismo , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Glicemia/metabolismo , Códon de Terminação/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 2/genética , Transportador de Glucose Tipo 2/metabolismo , Humanos , Rim/metabolismo , Masculino , Camundongos , Camundongos Mutantes , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transportador 1 de Glucose-Sódio/genética , Transportador 1 de Glucose-Sódio/metabolismo , Transportador 2 de Glucose-Sódio/química , Transportador 2 de Glucose-Sódio/metabolismo
17.
Regul Pept ; 194-195: 55-62, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25229126

RESUMO

Galanin is a neuropeptide expressed in the central and peripheral nervous systems. Galanin is known to be biosynthesized in neural and endocrine cells, but little evidence exists for its synthesis in other cells. In this study, we explored galanin-releasing nonneural cells using radioimmunoassay, finding that some fibroblasts produced and released the galanin-like immunoreactive component (galanin-LI). The molecular weight of the galanin-LI obtained from the fibroblasts, as measured by gel filtration chromatography and Western blotting, was 14 kDa and suggested that the compound was progalanin. Peptide mass fingerprinting analysis identified the large form of galanin-LI as progalanin without its signal sequence. In addition, galanin-LI was located in the Golgi bodies and vesicle-like structures of the fibroblasts. Furthermore, the addition of brefeldin A, an inhibitor of transport from the ER, decreased the release of galanin-LI. In this study, we showed that the fibroblast, a nonneural and nonendocrine cell type, produced and released a galanin precursor, progalanin, without processing via Golgi bodies or secretory vesicles.


Assuntos
Fibroblastos/metabolismo , Galanina/biossíntese , Galanina/metabolismo , Animais , Células Cultivadas , Galinhas , Cricetulus , Galanina/química , Humanos , Camundongos
18.
Protein Pept Lett ; 21(6): 517-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24345292

RESUMO

Energy homeostasis is regulated by endocrine factors. The concentration of relaxin-3 in serum is related to body mass index. However, relaxin-3 is found only in the brain and testis. In this study, we examined the expression of relaxin- 3 in adipose tissue and its effects on adipogenesis. The expression of relaxin-3 was determined using RT-PCR, a relaxin- 3 C-peptide-specific radioimmunoassay, specifically in the stromal-vascular fraction (SVF) cells rather than adipocytes. The release of C-peptide was regulated by glucose concentration in the SVF cells. However, the differentiated adipocytes did not express relaxin-3. In glucose perfusion experiments, C-peptide was released in response to high glucose concentrations in the mesenteric perfusate, opposite to insulin release. Additionally, GPCR135 mRNA was expressed in adipocytes. Relaxin-3 increased triglycerides in adipocytes and decreased lipase activity. The present study showed that relaxin-3 is secreted from SVF cells and that it regulates lipid accumulation in adipocytes.


Assuntos
Adipogenia , Tecido Adiposo/metabolismo , Metabolismo dos Lipídeos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Relaxina/genética , Relaxina/metabolismo , Animais , Células Cultivadas , Expressão Gênica , Masculino , Proteínas do Tecido Nervoso/análise , RNA Mensageiro/genética , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Relaxina/análise
19.
Pharmacol Biochem Behav ; 111: 128-35, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24051231

RESUMO

PURPOSE: Theanine, an amino acid in tea, has significant anti-stress effect on experimental animals under psychosocial stress. Anti-stress effect of theanine on humans was evaluated in 5th-year university students during pharmacy practice. METHOD: The study design was a single-blind group comparison and participants (n=20) were randomly assigned to theanine or placebo groups. Theanine or placebo (lactose) tablets (200 mg, twice a day, after breakfast and lunch) were taken from 1 week prior to the pharmacy practice and continued for 10 days in the practice period. To assess the anxiety of the participants, the state-trait anxiety inventory test was carried out before the pharmacy practice. Salivary α-amylase activity (sAA) was measured as a marker of sympathetic nervous system activity. RESULTS: In the placebo-group, sAA in the morning (pre-practice sAA) was higher than in theanine-group during the pharmacy practice (p=0.032). Subjective stress was significantly lower in the theanine-group than in the placebo-group (p=0.020). These results suggest that theanine intake had anti-stress effect on students. Furthermore, students with higher pre-practice sAA showed significantly higher trait anxiety in both groups (p=0.015). Similarly, higher pre-practice sAA was correlated to shorter sleeping time in both groups (p=0.41×10(-3)). CONCLUSION: Stressful condition increased the level of sAA that was essentially affected by individual trait anxiety. The low levels of pre-practice sAA and subjective stress in the theanine-group suggest that theanine intake suppressed initial stress response of students assigned for a long-term commitment of pharmacy practice.


Assuntos
Educação em Farmácia , Glutamatos/uso terapêutico , Saliva/enzimologia , Estresse Psicológico/tratamento farmacológico , Estudantes/psicologia , alfa-Amilases/metabolismo , Adulto , Feminino , Humanos , Masculino , Placebos , Método Simples-Cego , Recursos Humanos , Adulto Jovem
20.
Biochem Biophys Res Commun ; 430(3): 999-1004, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23261456

RESUMO

Progalanin is released from the small cell lung carcinoma line SBC-3A and converted to its active form by plasmin. To elucidate the role of progalanin activation in the extracellular compartment, matrix metalloproteinase (MMP) activity was studied in SBC-3A cells treated with progalanin siRNA, and angiogenesis was measured in tumor tissue originating from SBC-3A cell transplantation into mice. Progalanin siRNA caused downregulation of progalanin expression for approximately 8 days. MMP activity and angiogenesis were reduced in tumors induced by transplantation of progalanin siRNA-treated SBC-3A cells. In contrast, MMP-9 and MMP-2 activity and angiogenesis increased in tumors originating from progalanin siRNA-treated SBC-3A cells in the presence of galanin and progalanin. Furthermore, injection of tranexamic acid, a plasmin inhibitor, more markedly reduced MMP-9 and MMP-2 activity and angiogenesis in tumors originating from progalanin siRNA-treated SBC-3A cells and in tumor tissue originating from progalanin siRNA-treated SBC-3A cells in the presence of progalanin. The reduction of MMP-9 and MMP-2 activity with tranexamic acid was restored by galanin, but not by progalanin. Moreover, tranexamic acid reduced angiogenesis in control siRNA-treated SBC-3A cells. These results suggest that the activation of progalanin by plasmin in the extracellular compartment was involved in MMP-9 and MMP-2 activation and in angiogenesis in tumor tissue.


Assuntos
Galanina/metabolismo , Neoplasias Pulmonares/irrigação sanguínea , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Patológica/metabolismo , Carcinoma de Pequenas Células do Pulmão/irrigação sanguínea , Animais , Linhagem Celular Tumoral , Fibrinolisina/metabolismo , Galanina/genética , Humanos , Camundongos , Transplante de Neoplasias , Neovascularização Patológica/genética , RNA Interferente Pequeno/genética , Ratos
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