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1.
Nat Commun ; 12(1): 5059, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429413

RESUMO

With the current interest in cultured meat, mammalian cell-based meat has mostly been unstructured. There is thus still a high demand for artificial steak-like meat. We demonstrate in vitro construction of engineered steak-like tissue assembled of three types of bovine cell fibers (muscle, fat, and vessel). Because actual meat is an aligned assembly of the fibers connected to the tendon for the actions of contraction and relaxation, tendon-gel integrated bioprinting was developed to construct tendon-like gels. In this study, a total of 72 fibers comprising 42 muscles, 28 adipose tissues, and 2 blood capillaries were constructed by tendon-gel integrated bioprinting and manually assembled to fabricate steak-like meat with a diameter of 5 mm and a length of 10 mm inspired by a meat cut. The developed tendon-gel integrated bioprinting here could be a promising technology for the fabrication of the desired types of steak-like cultured meats.


Assuntos
Bioimpressão/métodos , Géis , Carne , Tendões , Animais , Bovinos , Técnicas de Cultura de Células , Colágeno , Células Endoteliais , Músculos/citologia , Músculos/fisiologia , Impressão Tridimensional , Células-Tronco , Tendões/citologia , Engenharia Tecidual
2.
Prev Nutr Food Sci ; 20(4): 238-45, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26770910

RESUMO

A non-protein amino acid, L-ornithine (Orn), has been shown to stimulate the urea cycle and tissue protein synthesis in the liver. The purpose of the current study was to assess whether Orn affects the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) pathway, which is involved in protein synthesis. Primary cultured cells isolated from Wistar rat liver were incubated in an amino acid-free medium, followed by addition of Orn for 3 h. The cell lysate was subjected to immunoblotting to evaluate the phosphorylation of downstream targets of mTORC1, including p70S6K, S6, and 4EBP1. To assess the involvement of mTORC1 for the effect of Orn, the cells were pretreated with the mTOR inhibitor rapamycin before the addition of Orn and the cell lysate was subjected to immunoblotting. We next examined whether the effects of Orn were exerted in vivo. Orn was orally administered to 18 h food-deprived rats, the blood and the livers were collected at 1 and 3 h after administration for immunoblotting. Orn treatment for primary cultured cells for 3 h enhanced the phosphorylation of p70S6K, S6, and 4EBP1. In addition, rapamycin blocked the effects of Orn completely (p70S6K and S6) or partially (4EBP1). The oral administration of Orn to the rat also augmented the phosphorylation of mTORC1 downstream targets notably in S6 at 1 h. Our findings demonstrate that Orn has the potential to induce the phosphorylation of downstream targets of mTORC1 in the rat liver. This may be mediated by the augmentation of mTORC1 activity.

3.
Cancer Lett ; 235(1): 121-9, 2006 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-15946793

RESUMO

This study evaluated the modulating effect of non-alcoholic constituents of beer on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced mammary carcinogenesis. Female Sprague-Dawley (SD) rats at 6 weeks of age were divided into four groups (n=26-30) and fed either a high fat diet or high fat diets containing 1, 2 or 4% freeze-dried beer (FD beer). One week after the start of feeding, rats received PhIP at a dose of 85 mg/kg by gavage four times weekly for 2 weeks. There were no differences in the body weights or diet intakes of rats between the control and the experimental groups. Weekly observation of palpable tumors indicated that tumor incidence and tumor multiplicity in the 2 and 4% FD beer groups were lower than in the control group throughout the experiment. Neoplastic lesions were pathologically examined at the end of the 22-weeks experiment. Tumor development was inhibited by FD beer intake in a dose-dependent manner. Tumor incidence (38.5%) and tumor multiplicity (0.8+/-0.4) for the group fed with a diet containing 4% FD were significantly reduced as compared with the control group (73.3% and 1.8+/-0.7). Supplementation with FD beer for 3 weeks together with the PhIP treatments resulted in increased liver GST activity, decreased liver CYP1A2 activity and a decrease in the number of DNA adducts in the mammary tissue, though these values were not significant. In conclusion, our results suggest that intake of FD beer may reduce the risk of carcinogenesis caused by heterocyclic amines.


Assuntos
Cerveja , Liofilização , Imidazóis/toxicidade , Neoplasias Mamárias Experimentais/prevenção & controle , Animais , Peso Corporal/efeitos dos fármacos , Carcinógenos , Citocromo P-450 CYP1A2/metabolismo , Adutos de DNA , Gorduras na Dieta , Suplementos Nutricionais , Feminino , Glutationa Transferase/metabolismo , Incidência , Fígado/enzimologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/enzimologia , Ratos , Ratos Sprague-Dawley
4.
Biochem Biophys Res Commun ; 336(3): 754-61, 2005 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-16140264

RESUMO

We have examined the modulating action of xanthohumol (XN) on the farnesoid X receptor (FXR) in vitro and in vivo. In the transient transfection assay, XN dose-dependently increased the BSEP promoter-driven luciferase activity. XN-fed KK-A(y) mice exhibited lowered levels of plasma glucose, plasma, and hepatic triglyceride. They also showed decreased amounts of water intake, lowered weights of white adipose tissue, and exhibited increased levels of plasma adiponectin, indicating that XN attenuated diabetes in KK-A(y) mice. The hepatic gene expression of XN-fed mice showed lowered levels of SREBP-1c including its targets involved in fatty acid synthesis and lowered levels of gluconeogenetic genes. However, the expression of cholesterol 7-hydroxylase (CYP7A1) was significantly induced in the liver of XN-fed mice. From the present results, it is suggested that XN acts on FXR through a selective bile acid receptor modulator (SBARM) like guggulsterone or polyunsaturated fatty acids, which have previously been reported as SBARMs.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Metabolismo dos Lipídeos , Propiofenonas/farmacologia , Fatores de Transcrição/metabolismo , Adiponectina , Tecido Adiposo/patologia , Animais , Glicemia/análise , Linhagem Celular Tumoral , Chalconas/química , Chalconas/farmacologia , Ácido Quenodesoxicólico/farmacologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Flavonoides , Expressão Gênica/efeitos dos fármacos , Humanos , Humulus/química , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Ligantes , Fígado/metabolismo , Masculino , Camundongos , Camundongos Obesos , Propiofenonas/química , Receptores Citoplasmáticos e Nucleares , Triglicerídeos/sangue , Triglicerídeos/metabolismo
5.
Mol Nutr Food Res ; 49(8): 772-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15968705

RESUMO

Male Fischer 344 rats were subcutaneously injected with azoxymethane (AOM) twice weekly at a dose of 15 mg/kg and were fed with freeze-dried (FD) samples of beer brewed without hops (non-hops beer), beer with hops at 4 times the amount of regular lager beer (x 4-hops beer), and isomerized hop extract (IHE) for the whole experimental period (I/PI) or for the post-initiation period (PI) only. Feeding FD beer samples at a dose of 1% significantly decreased the number of aberrant cryp foci (ACF) in the PI protocol over five weeks.x4-hops beer showed stronger inhibitory effects on the development of the numbers of aberrant crypts per focus and large ACF with four or more crypts than non-hops beer. Feeding IHE to rats at a dose of 0.01% or 0.05% in either the I/PI or PI experiment significantly reduced the numbers of ACF. Prostaglandin E2 (PGE2) levels in colonic mucosa of AOM-treated rats were significantly reduced by feeding of IHE. PGE2 production induced by lipopolysaccharide/interferon-gamma (LPS/IFN-gamma) in RAW264.7 cells was also reduced by treatment with IHE and isohumulone in a dose-dependent manner. These observations suggest that isohumulones show chemopreventive effects on ACF formation in rat colon by inhibiting the production of PGE2.


Assuntos
Colo/química , Neoplasias do Colo/prevenção & controle , Ciclopentanos/administração & dosagem , Dinoprostona/análise , Lesões Pré-Cancerosas/prevenção & controle , Animais , Azoximetano/administração & dosagem , Cerveja , Carcinógenos/administração & dosagem , Linhagem Celular , Colo/metabolismo , Suplementos Nutricionais , Dinoprostona/biossíntese , Interferon gama/farmacologia , Mucosa Intestinal/metabolismo , Ionóforos/administração & dosagem , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Lesões Pré-Cancerosas/induzido quimicamente , Ratos , Ratos Endogâmicos F344
6.
J Nat Prod ; 68(1): 43-9, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15679315

RESUMO

The ethyl acetate soluble fraction of hops (Humulus lupulus) showed potent inhibitory activity on the production of nitric oxide (NO) induced by a combination of LPS and IFN-gamma. Four known prenylflavonoids (1-4) and a new prenylflavonoid (5), hulupinic acid (6), lupulone (7), and its six new derivatives (8-13) were isolated from the active fraction. The structures were determined on the basis of physiochemical properties and spectroscopic analysis. Their inhibitory activities on the production of NO in macrophage RAW 264.7 cells were examined.


Assuntos
Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Humulus/química , Macrófagos/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/antagonistas & inibidores , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Plantas Medicinais/química , Animais , Células Cultivadas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/química , Floroglucinol/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação
7.
Mutat Res ; 559(1-2): 177-87, 2004 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-15066585

RESUMO

Anti-mutagenic and anti-carcinogenic effects of beer on heterocyclic amine (HCA)-induced carcinogenesis were studied in vitro and in vivo. Four commercial beers (two pilsner-type, black, and stout) showed inhibitory effects against five HCAs, 2-amino-3,8-dimethylimidazo [4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1) and 2-amino-3-methylimidazo[4,5-f]-quinoline (IQ), in the Ames assay using Salmonella typhimurium TA98 in the presence of rat S9 mix. The inhibitory effects of dark-colored beers (stout and black beer) were greater than those of pilsner-type beers. Dark-colored beers suppressed CYP1A2 activity in a dose-dependent manner, suggesting that inhibition of HCA activation is partly responsible for their strong anti-mutagenic effects. Anti-mutagenic effects were also observed when the pooled human S9 mix or activated IQ was used in the assay. The micronucleus test using Chinese hamster lung CHL/IU cells showed that the addition of freeze-dried samples of pilsner-type and stout beer to the culture medium significantly reduced the number of cells with micronuclei induced with PhIP or Trp-P-2. Single-cell gel electrophoresis assay (comet assay) revealed that oral ingestion of pilsner-type and stout beers for 1 week significantly inhibited DNA damage in the liver cells of male ICR mice exposed to MeIQx (13 mg/kg, i.p.). A decrease in the formation of DNA adducts was also observed using a 32P-postlabeling method. Male Fischer 344 rats orally received PhIP (75 mg/kg, five times a week for 2 weeks) and aberrant crypt foci (ACF) formation in the colon was analyzed after 5 weeks. The number of ACF was significantly reduced in rats fed a diet containing freeze-dried beer. These results suggest that beer inhibits the genotoxic effects of HCAs and may reduce the risk of carcinogenesis caused by food borne carcinogens.


Assuntos
Aminas/antagonistas & inibidores , Antimutagênicos/farmacologia , Cerveja/análise , Dano ao DNA , Compostos Heterocíclicos/antagonistas & inibidores , Mutagênese/efeitos dos fármacos , Animais , Antimutagênicos/análise , Células Cultivadas , Colo/patologia , Ensaio Cometa , Cricetinae , Cricetulus , Citocromo P-450 CYP1A2/metabolismo , Sistema Enzimático do Citocromo P-450/análise , Adutos de DNA/análise , Relação Dose-Resposta a Droga , Fígado/química , Testes para Micronúcleos , Oxirredutases/análise , Ratos , Salmonella typhimurium/efeitos dos fármacos , Espectrometria de Fluorescência
8.
Int J Cancer ; 108(3): 404-11, 2004 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-14648707

RESUMO

Modulatory effects of beer consumption on azoxymethane (AOM)-induced rat colonic carcinogenesis in male Fischer 344 rats were investigated. Single cell gel electrophoresis assay indicated that DNA damage of colonocytes, induced by a single AOM injection (15 mg/kg body weight), was significantly reduced in rats fed beer or malt extract for 2 weeks. Examination of aberrant crypt foci (ACF) formation in colonic mucosa, induced by AOM (15 mg/kg body weight; twice weekly), revealed that feeding of beer during the whole experimental period of 5 weeks significantly reduced the number of ACF by 35%. In the post-initiation protocol, a reduction in ACF formation by 26% was not significant. The efficacy in inhibition of ACF formation varied with the brand of beer. ACF formation was significantly reduced in rats treated with freeze-dried beer (FD Beer), but not with ethanol, suggesting that nonvolatile components of beer are responsible for the reduction. Significant suppression of ACF formation was observed in groups treated with hot water extract of malt, especially with extracts of colored malts, although no reduction was observed by feeding with hops extract. A long-term experiment of 42 weeks indicated that intake of beer decreased tumor incidence by 22% and decreased the number of neoplastic lesions, including adenocarcinomas and adenomas, by 44%. These results suggest that components of beer have chemopreventive effects on colonic carcinogenesis induced by AOM and that intake of beer may contribute to a reduction in the risk of cancer susceptibility.


Assuntos
Azoximetano/toxicidade , Cerveja , Carcinógenos/toxicidade , Neoplasias do Colo/prevenção & controle , Mucosa Intestinal/efeitos dos fármacos , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/patologia , Adenocarcinoma/prevenção & controle , Adenoma/induzido quimicamente , Adenoma/patologia , Adenoma/prevenção & controle , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Mucosa Intestinal/patologia , Masculino , Ratos , Ratos Endogâmicos F344
9.
Biol Pharm Bull ; 26(1): 61-5, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12520174

RESUMO

Nitric oxide (NO) plays an important role in many inflammatory responses and is also involved in carcinogenesis. In the present study, we investigated the inhibitory effect of extracts from Humulus lupulus L. on both the production of NO and the expression of inducible NO synthase (iNOS) in mouse macrophage RAW 264.7 cells. The production of NO was induced by a combination of lipopolysaccharide (LPS) and IFN-gamma, and determined by Griess assay. The expression of iNOS was detected by Western blotting. The LPS/IFN-gamma-induced production of NO and expression of iNOS were significantly inhibited by the ethyl acetate soluble fraction of Humulus lupulus L. Through bioactivity guided fractionation, humulene, five chalcones, 2,2-di-(3-methyl-2-butyleyl)-4,5-dihydoxy-cyclopent-4-en-1,3-dione, lupulone and three of its derivatives were isolated from the ethyl acetate soluble fraction. The chalcones, including xanthohumol, significantly inhibited the production of NO by suppressing the expression of iNOS.


Assuntos
Inibidores Enzimáticos/farmacologia , Humulus , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/antagonistas & inibidores , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humulus/química , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
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