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1.
J Ethnopharmacol ; 271: 113780, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33421600

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Epimedium brevicornu Maxim, Dioscorea nipponica Makino, and Salvia miltiorrhiza Bunge formula (EDS) are three traditional Chinese medicines commonly combined and used to treat osteoarthritis (OA). However, the mechanism of its therapeutic effect on OA is still unclear. AIM OF THE STUDY: The aim of this study was to investigate the potential anti osteoarthritis mechanism of EDS in the treatment of OA rats' model by quantitative proteomics. MATERIALS AND METHODS: A papain-induced rat OA model was established, and then EDS was intragastrically administered for 28 days. A label-free quantification proteomics was performed to evaluate the holistic efficacy of EDS against OA and identify the possible protein profiles mechanisms. The expression levels of critical changed proteins were validated by RT-qPCR and Western blotting. The effects of EDS were then assessed by evaluating pathologic changes in the affected knee joint and measuring pressure pain threshold, acoustic reflex threshold, angle of joint curvature. RESULTS: Proteomics analysis showed that 62 proteins were significantly upregulated and 208 proteins were downregulated in OA group compared to control group. The changed proteins were involved in activation of humoral immunity response, complement cascade activation, leukocyte mediated immunity, acute inflammatory response, endocytosis regulation, and proteolysis regulation. The EDS treatment partially restored the protein profile changes. The protective effects of EDS on pathologic changes in OA rats' knee joint and pain threshold assessment were consisted with the proteomics results. CONCLUSIONS: The results suggest that EDS exerted synergistic therapeutic efficacies to against OA through suppressing inflammation, modulating the immune system, relieving joint pain, and attenuating cartilage degradation.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Imunidade/efeitos dos fármacos , Inflamação/prevenção & controle , Osteoartrite/prevenção & controle , Animais , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Proteínas do Sistema Complemento/efeitos dos fármacos , Proteínas do Sistema Complemento/genética , Proteínas do Sistema Complemento/metabolismo , Citocinas/sangue , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Imunidade/genética , Inflamação/imunologia , Articulação do Joelho/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Osteoartrite/induzido quimicamente , Osteoartrite/imunologia , Osteoartrite/patologia , Limiar da Dor/efeitos dos fármacos , Papaína/toxicidade , Proteoma/efeitos dos fármacos , Proteoma/genética , Proteoma/imunologia , Proteômica/métodos , Ratos Wistar , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo
2.
Am J Physiol Endocrinol Metab ; 310(8): E699-E713, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-26884386

RESUMO

Neonatal pigs are used as a model to study and optimize the clinical treatment of infants who are unable to maintain oral feeding. Using this model, we have shown previously that pulsatile administration of leucine during continuous feeding over 24 h via orogastric tube enhanced protein synthesis in skeletal muscle compared with continuous feeding alone. To determine the long-term effects of leucine pulses, neonatal piglets (n = 11-12/group) were continuously fed formula via orogastric tube for 21 days, with an additional parenteral infusion of either leucine (CON + LEU; 800 µmol·kg-1·h-1) or alanine (CON + ALA) for 1 h every 4 h. The results show that body and muscle weights and lean gain were ∼25% greater, and fat gain was 48% lower in CON + LEU than CON + ALA; weights of other tissues were unaffected by treatment. Fractional protein synthesis rates in longissimus dorsi, gastrocnemius, and soleus muscles were ∼30% higher in CON + LEU compared with CON + ALA and were associated with decreased Deptor abundance and increased mTORC1, mTORC2, 4E-BP1, and S6K1 phosphorylation, SNAT2 abundance, and association of eIF4E with eIF4G and RagC with mTOR. There were no treatment effects on PKB, eIF2α, eEF2, or PRAS40 phosphorylation, Rheb, SLC38A9, v-ATPase, LAMTOR1, LAMTOR2, RagA, RagC, and LAT1 abundance, the proportion of polysomes to nonpolysomes, or the proportion of mRNAs encoding rpS4 or rpS8 associated with polysomes. Our results demonstrate that pulsatile delivery of a leucine supplement during 21 days of continuous enteral feeding enhances lean growth by stimulating the mTORC1-dependent translation initiation pathway, leading to protein synthesis in skeletal muscle of neonates.


Assuntos
Leucina/farmacologia , Proteínas Musculares/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Alanina/farmacologia , Sistema A de Transporte de Aminoácidos/efeitos dos fármacos , Sistema A de Transporte de Aminoácidos/metabolismo , Animais , Animais Recém-Nascidos , Músculos do Dorso , Suplementos Nutricionais , Nutrição Enteral , Infusões Parenterais , Leucina/administração & dosagem , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Complexos Multiproteicos/efeitos dos fármacos , Complexos Multiproteicos/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Fosforilação/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/genética , Sus scrofa , Suínos , Serina-Treonina Quinases TOR/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
3.
J Nat Prod ; 77(2): 250-7, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24456004

RESUMO

Since the administration of synthetic medicines is associated with drug resistance and undesired side effects, utilization of natural compounds could be an alternative and complementary modality to inhibit or prevent the development of tumors. Epigallocatechin 3-O-gallate (EGCG, 1), the major flavan component of green tea, and genistein (2), a soy isoflavonoid, are known to have chemopreventive and chemotherapeutic effects against cancer. This study demonstrated that both flavonoids inhibit cell proliferation, an effect enhanced under serum-free conditions. Compound 1, but not 2, induced downregulation of ErbB1 and ErbB2 in mammary and epidermoid carcinoma cells, and its inhibitory effect on cell viability was mediated by the 67 kDa laminin receptor (67LR). While 1 was superior in inducing cell death, 2 was more efficient in arresting the tumor cells in the G2/M phase. Furthermore, number and brightness analysis revealed that 1 decreased the homoclustering of a lipid raft marker, glycosylphosphatidylinositol-anchored GFP, and it also reduced the co-localization between lipid rafts and 67LR. The main conclusion made is that the primary target of 1 may be the lipid raft component of the plasma membrane followed by secondary changes in the expression of ErbB proteins. Compound 2, on the other hand, must have other unidentified targets.


Assuntos
Anticarcinógenos/química , Anticarcinógenos/farmacologia , Catequina/análogos & derivados , Flavonoides/farmacologia , Genisteína/farmacologia , Receptores de Laminina/efeitos dos fármacos , Proteínas Ribossômicas/efeitos dos fármacos , Chá/química , Algoritmos , Anticarcinógenos/isolamento & purificação , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Catequina/química , Catequina/isolamento & purificação , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Flavonoides/química , Flavonoides/isolamento & purificação , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Pontos de Checagem da Fase G2 do Ciclo Celular/fisiologia , Genes erbB-1/genética , Genes erbB-1/fisiologia , Genes erbB-2/genética , Genes erbB-2/fisiologia , Genisteína/química , Genisteína/isolamento & purificação , Humanos , Estrutura Molecular , Polifenóis/farmacologia , Receptores de Laminina/genética , Receptores de Laminina/metabolismo , Receptores de Laminina/fisiologia , Glycine max/química
4.
Int J Toxicol ; 30(1): 21-34, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20959614

RESUMO

The current study aims to evaluate the antioxidative and antimutagenic activities of methanol extract and different fractions of Chukrasia tabularis leaves. The antioxidative potential was evaluated using 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation and superoxide anion radical-scavenging assay. The antimutagenic potential was evaluated against direct-acting mutagens, 4-nitro-o-phenylenediamine and sodium azide; and S9-dependent mutagen, 2-aminofluorene in TA98 and TA100 strains of Salmonella typhimurium using Ames assay. It has been found that methanol extract and its fractions were more efficient against S9-dependent mutagen in pre-incubation mode of treatment as compared to direct-acting mutagens in both the strains. Methanol extract and its fractions also exhibited strong radical-scavenging potential. High-performance liquid chromatography (HPLC) analysis of methanol extract showed the presence of gallic acid, epicatechin, 7-hydroxycoumarin, and rutin. From the study, it could be concluded that antioxidative and antimutagenic activity of methanol extract and its fractions was related to the synergistic interactions among different chemical compounds.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Meliaceae/química , Animais , Antimutagênicos/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , DNA/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Antagonismo de Drogas , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Masculino , Microssomos Hepáticos , Mutagênicos/toxicidade , Folhas de Planta/química , Ratos , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
5.
Toxicol In Vitro ; 24(6): 1871-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20624453

RESUMO

The aim of the current study was to evaluate the potential mutagenicity of aluminium oxide nanomaterials (NMs) (Al(2)O(3)-30 nm and Al(2)O(3)-40 nm). Characterization of the NMs was done before the initiation of the study. The mutagenicity of the NMs was studied by the Ames test with Salmonella typhimurium TA100, TA1535, TA98, TA97a and TA102 strains, in the presence and absence of the S9 mixture. Based on a preliminary cytotoxicity study conducted on the strains, different concentrations of Al(2)O(3)-30 nm, Al(2)O(3)-40 nm and Al(2)O(3)-bulk were selected. At all the concentrations tested, Al(2)O(3)-30 nm and Al(2)O(3)-40 nm did not significantly increase the number of revertant colonies compared to the Al(2)O(3)-bulk and control with or without S9 mixture. Our findings suggest that Al(2)O(3) NMs were devoid of any size and concentration dependent mutagenicity compared to the Al(2)O(3)-bulk and control.


Assuntos
Óxido de Alumínio/toxicidade , Nanopartículas Metálicas/toxicidade , Mutagênicos/efeitos adversos , Proteínas Ribossômicas/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Óxido de Alumínio/classificação , Óxido de Alumínio/metabolismo , Animais , Fracionamento Celular , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Microssomos Hepáticos , Mutagênicos/classificação , Mutagênicos/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína S9 Ribossômica , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
6.
Regul Toxicol Pharmacol ; 55(2): 158-65, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19559745

RESUMO

In this paper a sub-chronic (13 weeks) toxicity study in rats and an in vitro genotoxicity study with Korean pine (Pinus koraiensis Siebold & Zucc.) nut oil, KPNO (PinnoThin) are described. Both studies were performed in compliance with GLP, and in line with OECD guidelines applicable. In the sub-chronic toxicity study, no clinical signs, abnormalities in functional observation tests or ophthalmologic examinations or changes in body weight or food intake were noted at any of the doses of KPNO tested. Various changes in clinical biochemistry parameters were noted. Whilst these changes were not consistent in both sexes, and neither associated with any histopathological changes, nor dose-related, these were not considered to be toxicologically relevant. No toxicologically significant changes were noted in haematological parameters. There were a few histopathological observations such as a periportal vacuolation of the liver in all dose groups including the control, and renal tubular mineralisation in most females of the high dose group but also in all control female rats. These findings can be considered to be due to the high fat content of the diets, and are not related to the treatment with KPNO. Based on these findings a No Observable Adverse Effect Level (NOAEL) of 15% has been established for KPNO. This NOAEL corresponded to a mean of 8866 and 10,242 mg KPNO/kg bw/day for males and females, respectively. This dose level was the highest achievable oral dose for KPNO in rats. The in vitro reverse mutation test (Ames test), showed no significant dose-related increase in the number of revertants in two independently repeated mutation assays. The negative and strain-specific positive control values were within the laboratory historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly. Based on these results it has been concluded that KPNO is not mutagenic in the Escherichia coli and Salmonella typhimurium reverse mutation assays. In conclusion, KPNO can be considered to be non-genotoxic in the AMES test. A NOAEL of 8866 and 10,242 mg KPNO/kg bw/day has been established for male and female rats, respectively. For both sexes, the NOAEL was achieved at the highest dose tested.


Assuntos
Mutagênicos/toxicidade , Nozes/química , Pinus/química , Óleos de Plantas/toxicidade , Administração Oral , Animais , DNA Bacteriano/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Testes de Mutagenicidade , Mutagênicos/metabolismo , Nível de Efeito Adverso não Observado , Óleos de Plantas/metabolismo , Ratos , Ratos Wistar , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Organismos Livres de Patógenos Específicos , Testes de Toxicidade
7.
Drug Chem Toxicol ; 32(3): 283-92, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19538026

RESUMO

For centuries, plants have been used in traditional medicines, and there has been recent interest in the chemopreventive properties of compounds derived from plants. In the present study, we investigated the free-radical-scavenging, antioxidant, and antimutagenic potential of polar extracts from Phlomis crinita Cav. flowers. Ethyl acetate, chloroform, and methanol extracts were prepared from powdered Phlomis flowers and characterized for the presence of tannins, flavonoids, iridoids, sterols, cardiac glycosides, and anthraquinones. All the extracts showed increased activity in scavenging the ABTS free radical, but only ethyl acetate and methanol extracts were active in scavenging the superoxide anion generated by the xanthine/xanthine oxidase system. In addition, all the extracts significantly decreased the mutagenicity induced by 2-aminoanthracene in the presence of a metabolizing homogenate (S9) and methyl methane sulfonate in the absence of metabolizing system, using the Ames test with Salmonella typhimurium TA102 and TA104. The present study indicates that extracts of P. crinita flowers are a significant source of compounds with antigenotoxic and antioxidant activity (most likely phenolic compounds) and thus may be useful candidates for chemoprevention studies.


Assuntos
Antimutagênicos/farmacologia , Sequestradores de Radicais Livres/farmacologia , Phlomis/química , Extratos Vegetais/farmacologia , Animais , Antracenos/toxicidade , Flores/química , Metanossulfonato de Metila/toxicidade , Mutagênicos/toxicidade , Extratos Vegetais/isolamento & purificação , Ratos , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Solventes/química , Superóxidos/metabolismo , Tunísia , Xantina Oxidase/antagonistas & inibidores
8.
Toxicol In Vitro ; 22(5): 1264-72, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18515041

RESUMO

The total oligomers flavonoids (TOF), chloroform, petroleum ether and aqueous extracts from Acacia salicina, were investigated for the antioxidative, cytotoxic, antimutagenic and antigenotoxic activities. The viability of K562 cells were affected by all extracts after 48 h exposure. Our results showed that A. salicina extracts have antigenotoxic and/or antimutagenic activities. TOF and chloroform extracts exhibit antioxidant properties, expressed by the capacity of these extracts to inhibit xanthine oxidase activity. To further explore the mechanism of action of A. salicina extracts, we characterized expression profiles of genes involved in antioxidant protection and DNA repair in the human lymphoblastic cell line K562 exposed to H2O2. Transcription of several genes related to the thioredoxin antioxidant system and to the DNA base-excision repair pathway was up-regulated after incubation with chloroform, TOF and petroleum ether extracts. Moreover genes involved in the nucleotide-excision repair pathway and genes coding for catalase and Mn-superoxide-dismutase, two important antioxidant enzymes, were induced after incubation with the chloroform extract. Taken together, these observations provide evidence that the chloroform and TOF extracts of A. salicina leaves contain bioactive compounds that are able to protect cells against the consequences of an oxidative stress.


Assuntos
Acacia/química , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Medicina Tradicional , Oxidantes/farmacologia , Animais , Linhagem Celular Tumoral , Ensaio Cometa , DNA/efeitos dos fármacos , Combinação de Medicamentos , Flavonoides/química , Formazans/metabolismo , Perfilação da Expressão Gênica , Genes Bacterianos/efeitos dos fármacos , Humanos , Células K562/efeitos dos fármacos , Células K562/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Extratos Vegetais/farmacologia , Ratos , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Sais de Tetrazólio/metabolismo
9.
Food Chem Toxicol ; 44(11): 1868-74, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16901601

RESUMO

Salacia oblonga has been used for thousands of years in Ayurvedic medicine for the oral treatment of diabetes. The root extract has been shown to inhibit the activity of intestinal alpha-glucosidases, therefore S. oblonga holds potential as a natural method to mitigate the blood glucose response for people with diabetes. As part of a safety evaluation of novel ingredients for use in blood glucose control, the potential genotoxicity of a S. oblonga root extract (SOE) was evaluated using the standard battery of tests (reverse mutation assay; chromosomal aberrations assay; mouse micronucleus assay) recommended by US Food and Drug Administration (FDA) for food ingredients. SOE was determined not to be genotoxic under the conditions of the reverse mutation assay and mouse micronucleus assay, and weakly positive for the chromosomal aberrations assay. A reproducible, although weak, positive chromosomal aberrations response in human lymphocytes is of concern and further toxicity research is recommended. Use of SOE is presently expected to be safe, as anticipated intake is small compared to the doses administered in the genotoxicity assays and may, after further toxicity research, may prove be a useful ingredient in foodstuffs.


Assuntos
Inibidores Enzimáticos/toxicidade , Testes de Mutagenicidade , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Salacia/química , Animais , Aberrações Cromossômicas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Inibidores de Glicosídeo Hidrolases , Humanos , Masculino , Ayurveda , Camundongos , Camundongos Endogâmicos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mutagênicos/classificação , Mutagênicos/metabolismo , Extratos Vegetais/classificação , Extratos Vegetais/metabolismo , Plantas Medicinais , Ratos , Ratos Sprague-Dawley , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
10.
Food Chem Toxicol ; 44(9): 1522-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16757077

RESUMO

High dietary intake of lutein has been associated with risk reduction of many chronic diseases, including age-related macular degeneration (AMD), cancer, and cardiovascular diseases. Lutein in food is generally regarded as safe. However, information on the toxicological and beneficial effect of lutein at higher doses is limited. In this study, large amount of lutein was extracted and purified from marigold flower (Tagetes erecta L.). The antioxidant activity of lutein was examined by using the photochemiluminescence (PCL) assay and the beta-carotene-linoleic acid model system (beta-CLAMS). Lutein showed a greater antioxidant activity than the other two common carotenoids, beta-carotene and lycopene. The mutagenicity and anti-mutagenicity of lutein at 334, 668 and 1335 microg/plate were examined using the standard Ames test in the presence and absence of S9 mix. Lutein was not only found to be non-mutagenic at all doses, but it showed an anti-mutagenic effect in a dose-dependent manner. Similar results were found in a chromosome aberration test using Chinese hamster ovary cells for the evaluation of clastogenicity and anti-clastogenicity of lutein at 66.8, 133.5 and 267.0 mg/L. Our findings provided scientific evidence for the safe use and health beneficial effects of lutein.


Assuntos
Antimutagênicos , Antioxidantes , Células CHO/efeitos dos fármacos , Flores/química , Luteína , Mutagênicos , Tagetes , Animais , Antimutagênicos/metabolismo , Antimutagênicos/farmacologia , Antimutagênicos/toxicidade , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/toxicidade , Quebra Cromossômica , Cricetinae , Cricetulus , Luteína/metabolismo , Luteína/farmacologia , Luteína/toxicidade , Testes de Mutagenicidade , Mutagênicos/metabolismo , Mutagênicos/farmacologia , Mutagênicos/toxicidade , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Tagetes/química
11.
Food Chem Toxicol ; 44(9): 1530-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16753249

RESUMO

To reduce the incorporation of dietary lipids into adipose tissue, modified fats and oils have been developed, such as medium-chain triacylglycerols (MCT). Typical dietary lipids from vegetable oils, termed long-chain triacylglycerols (LCT), are degraded by salivary, intestinal and pancreatic lipases into two fatty acids and a monoacyl glycerol; whereas, MCT are degraded by the same enzymes into three fatty acids and the simple glycerol backbone. Medium-chain fatty acids (MCFA) are readily absorbed from the small intestine directly into the bloodstream and transported to the liver for hepatic metabolism, while long-chain fatty acids (LCFA) are incorporated into chylomicrons and enter the lymphatic system. MCFA are readily broken down to carbon dioxide and two-carbon fragments, while LCFA are re-esterified to triacylglycerols and either metabolized for energy or stored in adipose tissue. Therefore, consumption of MCT decreases the incorporation of fatty acids into adipose tissue. However, MCT have technological disadvantages precluding their use in many food applications. A possible resolution is the manufacture and use of a triacylglycerol containing both LCT and MCT, termed medium- and long-chain triacylglycerol (MLCT). This manuscript describes studies performed for the safety evaluation of a MLCT oil enzymatically produced from MCT and edible vegetable oil (containing LCT), by a transesterification process. The approximate fatty acid composition of this MLCT consists of caprylic acid (9.7%), capric acid (3.3%), palmitic acid (3.8%), stearic acid (1.7%), oleic acid (51.2%), linoleic acid (18.4%), linolenic acid (9.0%), and other fatty acids (2.9%). The approximate percentages of long (L) and medium (M) fatty acids in the triacylglyerols are as follows: L, L, L (55.1%), L, L, M (35.2%), L, M, M (9.1%), and M, M, M (0.6%). The studies included: (1) acute study in rats (LD50>5000 mg/kg); (2) 6 week repeat-dose safety study via dietary administration to rats (NOAEL of 3500 mg/kg/day), (3) in vitro genotoxicity studies using Salmonella typhimurium and Escherichia coli (negative at 5000 mg/plate), and (4) a four-week, placebo-controlled, double blind, human clinical trial utilizing 20 test subjects (no effects at 42 g MLCT/day). These data are corroborated by other studies published in the peer-reviewed literature on analogous MLCTs.


Assuntos
Gorduras Insaturadas na Dieta/toxicidade , Óleos de Plantas/toxicidade , Triglicerídeos/toxicidade , Administração Oral , Adulto , Animais , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Gorduras Insaturadas na Dieta/administração & dosagem , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Graxos/análise , Feminino , Humanos , Dose Letal Mediana , Masculino , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Óleos de Plantas/administração & dosagem , Óleos de Plantas/química , Ratos , Ratos Wistar , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Triglicerídeos/administração & dosagem , Triglicerídeos/química
12.
Food Chem Toxicol ; 44(9): 1585-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16730111

RESUMO

Strychnos pseudoquina St. Hil. is a native plant of the Brazilian Savannah, used in popular medicine to treat a number of conditions. Since it contains large quantities of alkaloids with proven antiulcer activity, we tested the genotoxic potential of crude extracts and fractions containing alkaloids and flavonoids from the leaves of this plant, on Salmonella typhimurium and performed the micronucleus test on peripheral blood cells of mice treated in vivo. The results showed that the methanol extract of the leaves of S. pseudoquina is mutagenic to the TA98 (-S9) and TA100 (+S9, -S9) strains of Salmonella. The dichloromethane extract was not mutagenic to any of the tested strains. Fractions enriched with alkaloids or flavonoids were not mutagenic. In vivo tests were done on the crude methanol extract in albino Swiss mice, which were treated, by gavage, with three different doses of the extract. The highest dose tested (1800 mg/kgb.w.) induced micronuclei after acute treatment, confirming the mutagenic potential of the methanol extract of the leaves of S. pseudoquina. In high doses, constituents of S. pseudoquina compounds act on DNA, causing breaks and giving rise to micronuclei in the blood cells of treated animals.


Assuntos
Antiulcerosos/toxicidade , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Strychnos , Administração Oral , Animais , Antiulcerosos/metabolismo , Fracionamento Químico , Relação Dose-Resposta a Droga , Feminino , Masculino , Metanol/química , Camundongos , Testes para Micronúcleos , Mutagênicos/metabolismo , Extratos Vegetais/metabolismo , Plantas Medicinais/química , Reticulócitos/efeitos dos fármacos , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Strychnos/química
13.
Biopharm Drug Dispos ; 26(1): 27-33, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15593345

RESUMO

PLD-118 is a novel, oral antifungal drug, under development for the treatment of Candida infections. Possible metabolism of PLD-118 by rat, dog and human S9 liver homogenates and inhibition of human cytochrome P450 (CYP) enzymes were investigated. PLD-118 (10 and 100 microM) incubated for 0-60 min with S9 fractions and NADPH was determined by HPLC, using the Waters AccQ.Tag method after derivatization of amino acids to stable, fluorescent derivatives. CYP assays were performed using pooled human liver microsomes with substrates, selective towards human CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A, incubated at concentrations around the Km. Incubation mixtures were preincubated with PLD-118 (0.1-100 microM) or control inhibitor for 5 min. No metabolism of PLD-118 was detected with rat and dog S9 fractions. A small (8%) decrease in PLD-118 at 100 microM (not detected at 10 microM) with human microsomes was considered to be biologically irrelevant. PLD-118 did not inhibit any of the tested CYPs. PLD-118, at concentrations up to 100 microM, is not metabolized by rat, dog or human liver S9 homogenates and does not inhibit human CYPs in vitro, suggesting little likelihood for interaction of PLD-118 with drugs metabolized by these enzymes.


Assuntos
Antifúngicos/farmacologia , Cicloleucina/análogos & derivados , Administração Oral , Animais , Antifúngicos/química , Química Farmacêutica/métodos , Cicloleucina/farmacologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Cães , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Ratos , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos
14.
Acta Pharmacol Sin ; 21(2): 179-82, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11263268

RESUMO

AIM: To determine whether trichobitacin, a novel ribosome-inactivating protein purified from the root tubers of Trichosanthes kirilowii, possesses the anti-HIV activity. METHODS: The inhibition of syncytial cell formation induced by human immunodeficiency virus type 1 (HIV-1) was determined under microscope, reduction of HIV-1 p24 antigen expression level was measured by ELISA, and decrease in numbers of HIV-1 antigen positive cells in acutely and chronically infected cultures were detected by indirect immunofluorescence assay. RESULTS: Trichobitacin was found to greatly suppress syncytial cell formation induced by HIV-1 and to markedly reduce both expression of HIV-1 p24 antigen and the number of HIV antigen positive cells in acutely but not chronically HIV-1 infected culture. The median inhibitory concentration (IC50) in inhibition of syncytial cell formation and HIV antigen positive cells were 5 micrograms.L-1 (95% confidence limits: 1.3-20 micrograms.L-1) and 0.09 mg.L-1 (95% confidence limits: 0.011-0.755 mg.L-1), respectively. CONCLUSION: Trichobitacin is a novel ribosome-inactivating protein with anti-HIV-1 activity.


Assuntos
Fármacos Anti-HIV/farmacologia , Proteína do Núcleo p24 do HIV/metabolismo , HIV-1/fisiologia , Proteínas de Plantas/farmacologia , Fármacos Anti-HIV/isolamento & purificação , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Cucurbitaceae/química , Medicamentos de Ervas Chinesas/química , Células Gigantes/citologia , Células Gigantes/virologia , Humanos , Proteínas de Plantas/isolamento & purificação , Proteínas Ribossômicas/efeitos dos fármacos , Replicação Viral
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