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1.
Biomed Pharmacother ; 167: 115457, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690389

RESUMO

Appropriate topical dressings for burn treatments are important to accelerate skin wound recovery and prevent external infections. This study aimed to evaluate the effect and investigate the mechanism of folium crataegi (Crataegus pinnatifida Bge.) for the treatment of burn wounds, as well as to compare the therapeutic effects of aqueous extracts (HLW) and alcoholic extracts (HLE) from folium crataegi. The results demonstrated that both HLW and HLE groups exhibited a higher wound contraction rate than the silver sulfadiazine (SSD) ointment group. Moreover, HLW showed more significant wound repair effects than HLE. HLW significantly increased levels of EGF and FGF-2 in wound tissue, as well as TGF-ß1, VEGF, CAT and IL-10 in serum. Folium crataegi extract, especially aqueous extracts, exerted good anti-inflammatory, anti-oxidant and anti-bacterial effects by upregulating the expression of lag3, txn1 and slpi, respectively. Folium crataegi extract significantly inhibits the expression of npas2, a key gene in the circadian rhythm pathway. In conclusion, this research illustrated that the folium crataegi extract, especially aqueous extracts, had better therapeutic effects on skin burns through multiple ways, possibly including a novel mechanism related to circadian rhythm pathway. These findings suggest that folium crataegi could be a valuable source of compounds for enhancing skin regeneration through multiple ways.


Assuntos
Queimaduras , Crataegus , Ratos , Animais , Pele , Sulfadiazina de Prata/farmacologia , Sulfadiazina de Prata/uso terapêutico , Cicatrização , Queimaduras/tratamento farmacológico
2.
Int J Mol Sci ; 25(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38203496

RESUMO

Diapause, an adaptative strategy for survival under harsh conditions, is a dynamic multi-stage process. Bombus terrestris, an important agricultural pollinator, is declining in the wild, but artificial breeding is possible by imitating natural conditions. Mated queen bees enter reproductive diapause in winter and recover in spring, but the regulatory mechanisms remain unclear. Herein, we conducted a comparative 4D label-free proteomic analysis of queen bees during artificial breeding at seven timepoints, including pre-diapause, diapause, and post-diapause stages. Through bioinformatics analysis of proteomic and detection of substance content changes, our results found that, during pre-diapause stages, queen bees had active mitochondria with high levels of oxidative phosphorylation, high body weight, and glycogen and TAG content, all of which support energy consumption during subsequent diapause. During diapause stages, body weight and water content were decreased but glycerol increased, contributing to cold resistance. Dopamine content, immune defense, and protein phosphorylation were elevated, while fat metabolism, protein export, cell communication, signal transduction, and hydrolase activity decreased. Following diapause termination, JH titer, water, fatty acid, and pyruvate levels increased, catabolism, synaptic transmission, and insulin signaling were stimulated, ribosome and cell cycle proteins were upregulated, and cell proliferation was accelerated. Meanwhile, TAG and glycogen content decreased, and ovaries gradually developed. These findings illuminate changes occurring in queen bees at different diapause stages during commercial production.


Assuntos
Diapausa , Proteômica , Abelhas , Animais , Peso Corporal , Glicogênio , Água
3.
Pharmaceuticals (Basel) ; 15(5)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35631427

RESUMO

As one of the most characteristic ingredients of glandular trichome secretions from Nicotiana tabacum L. (tobacco), natural cembrenediols, namely, (1S,2E,4S,6R,7E,11E)-2,7,11-cembratriene-4,6-diol (α-cembrenediol/α-CBD) and its C-4 epimer (ß-cembrenediol/ß-CBD), have attracted considerable attention for their potent antitumor, neuroprotective, antimicrobial, and other activities. Many researchers are committed to exploring the possibility of utilizing these two cembrenediols and their derivatives both in human medicine and in agricultural fungicides. To the best of our knowledge, this review is the first to provide a comprehensive summary of the chemical modifications and bioactivities of α- and ß-CBD from their discovery to the present day; the review highlights their potential medicinal value for humans. The extensive references from 1962 to 2022 provided herein were systematically gathered from the SciFinder, Web of Science, and Google Scholar databases. We expect this review to assist in providing practical ideas for future drug development based on α- and ß-CBD and in further facilitating the utilization of the tobacco cembrenediols.

4.
J Ethnopharmacol ; 258: 112932, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32376368

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese Medicine (TCM) has been widely used as an approach worldwide. Chinese Medicines (CMs) had been used to treat and prevent viral infection pneumonia diseases for thousands of years and had accumulated a large number of clinical experiences and effective prescriptions. AIM OF THE STUDY: This research aimed to systematically excavate the classical prescriptions of Chinese Medicine (CM), which have been used to prevent and treat Pestilence (Wenbing, Wenyi, Shiyi or Yibing) for long history in China, to obtain the potential prescriptions and ingredients to alternatively treat COVID-19. MATERIALS AND METHODS: We developed the screening system based on data mining, molecular docking and network pharmacology. Data mining and association network were used to mine the high-frequency herbs and formulas from ancient prescriptions. Virtual screening for the effective components of high frequency CMs and compatibility Chinese Medicine was explored by a molecular docking approach. Furthermore, network pharmacology method was used to preliminarily uncover the molecule mechanism. RESULTS: 574 prescriptions were obtained from 96,606 classical prescriptions with the key words to treat "Warm diseases (Wenbing)", "Pestilence (Wenyi or Yibing)" or "Epidemic diseases (Shiyi)". Meanwhile, 40 kinds of CMs, 36 CMs-pairs, 6 triple-CMs-groups existed with high frequency among the 574 prescriptions. Additionally, the key targets of SARS-COV-2, namely 3CL hydrolase (Mpro) and angiotensin-converting enzyme 2(ACE2), were used to dock the main ingredients from the 40 kinds by the LigandFitDock method. A total of 66 compounds components with higher frequency were docked with the COVID-19 targets, which were distributed in 26 kinds of CMs, among which Gancao (Glycyrrhizae Radix Et Rhizoma), HuangQin (Scutellariae Radix), Dahuang (Rhei Radix Et Rhizome) and Chaihu (Bupleuri Radix) contain more potential compounds. Network pharmacology results showed that Gancao (Glycyrrhizae Radix Et Rhizoma) and HuangQin (Scutellariae Radix) CMs-pairs could also interact with the targets involving in immune and inflammation diseases. CONCLUSIONS: These results we obtained probably provided potential candidate CMs formulas or active ingredients to overcome COVID-19. Prospectively, animal experiment and rigorous clinic studies are needed to confirm the potential preventive and treat effect of these CMs and compounds.


Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Pneumonia Viral/tratamento farmacológico , COVID-19 , Infecções por Coronavirus/virologia , Mineração de Dados , Humanos , Modelos Moleculares , Pandemias , Extratos Vegetais , Pneumonia Viral/virologia , Conformação Proteica , SARS-CoV-2 , Proteínas Virais
5.
Eur J Med Chem ; 177: 153-170, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31132531

RESUMO

The eukaryotic initiation factor 4E (eIF4E) is an emerging anticancer drug target for specific anticancer therapy as a promising approach to overcome drug resistance and promote chemotherapy antitumor efficacy. A series of bromophenol-thiazolylhydrazone hybrids were designed, synthesized and evaluated for their antitumor activities. Among of them, the most potent compound 3e (EGPI-1) could inhibit the eIF4E/eIF4G interaction. Further mechanism study demonstrated EGPI-1 played an antitumor role in multiple modes of action including regulating the activity of eIF4E by inhibiting the phosphorylation of eIF4E and 4EBP1, disrupting mitochondrial function through the mTOR/4EBP1 signaling pathway, and inducing autophagy, apoptosis and ROS generation. Moreover, EGPI-1 showed good safety and favorable pharmacokinetic properties in vivo. These observations demonstrate that EGPI-1 may serve as an excellent lead compound for the development of new anticancer drugs that target the eIF4E/eIF4G interface and as a chemical genetic probe to investigate the role of the eIF4E in biological processes and human diseases.


Assuntos
Antineoplásicos/farmacologia , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação Eucariótico 4G/antagonistas & inibidores , Hidrazonas/farmacologia , Tiazóis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrazonas/síntese química , Hidrazonas/farmacocinética , Hidrazonas/toxicidade , Masculino , Camundongos , Simulação de Acoplamento Molecular , Fosforilação , Ligação Proteica , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiazóis/síntese química , Tiazóis/farmacocinética , Tiazóis/toxicidade , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Med Chem ; 62(6): 3051-3067, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30844273

RESUMO

Poly(ADP-ribose) polymerase-1 (PARP-1) is a new potential target for anticancer drug discovery. A series of bromophenol-thiosemicarbazone hybrids as PARP-1 inhibitors were designed, synthesized, and evaluated for their antitumor activities. Among them, the most promising compound, 11, showed excellent selective PARP-1 inhibitory activity (IC50 = 29.5 nM) over PARP-2 (IC50 > 1000 nM) and potent anticancer activities toward the SK-OV-3, Bel-7402 and HepG2 cancer cell lines (IC50 = 2.39, 5.45, and 4.60 µM), along with inhibition of tumor growth in an in vivo SK-OV-3 cell xenograft model. Further study demonstrated that compound 11 played an antitumor role through multiple anticancer mechanisms, including the induction of apoptosis and cell cycle arrest, cellular accumulation of DNA double-strand breaks, DNA repair alterations, inhibition of H2O2-triggered PARylation, antiproliferative effects via the production of cytotoxic reactive oxygen species, and autophagy. In addition, compound 11 displayed good pharmacokinetic characteristics and favorable safety. These observations demonstrate that compound 11 may serve as a lead compound for the discovery of new anticancer drugs.


Assuntos
Antineoplásicos/uso terapêutico , Descoberta de Drogas , Neoplasias/tratamento farmacológico , Fenóis/química , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Tiossemicarbazonas/química , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Concentração Inibidora 50 , Camundongos , Neoplasias/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacocinética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Eur J Med Chem ; 166: 178-185, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30711829

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) has been considered as a validated biological target for type 2 diabetes treatment, but past endeavors to develop inhibitors of PTP1B into drugs have been unsuccessful. Two challenging aspects are selective inhibition and cell permeability. A structure-based strategy was employed to develop uncharged bromophenols as a new series of PTP1B inhibitors. The most potent compound 22 (LXQ46) inhibited PTP1B with an IC50 value of 0.190 µM, and showed remarkable selectivity over other protein tyrosine phosphatases (PTPs, 20-200 folds). In the SPR study, increasing concentrations of compound 22 led to concentration-dependent increases in binding responses, indicating that compound 22 could bind to the surface of PTP1B via noncovalent means. By treating insulin-resistant C2C12 myotubes with compound 22, enhanced insulin and leptin signaling pathways were observed. Long-term oral administration of compound 22 reduced the blood glucose level of diabetic BKS db mice. The glucose tolerance tests (OGTT) and insulin tolerance tests (ITT) in BKS db mice showed that oral administration of compound 22 could increase insulin sensitivity. In addition, long-term oral administration of compound 22 could protect mice from obesity, which was not the result of toxicity. Our pharmacokinetics results from the rat-based assays showed that orally administered compound 22 was absorbed rapidly from the gastrointestinal tract, extensively distributed to the tissues, and rapidly eliminated from the body. All these results indicate that compound 22 could serve as a qualified agent to treat type II diabetes.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Obesidade/complicações , Fenóis/química , Fenóis/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Insulina/metabolismo , Resistência à Insulina , Leptina/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Fenóis/farmacocinética , Fenóis/uso terapêutico , Fosforilação/efeitos dos fármacos , Conformação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 1/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Segurança , Transdução de Sinais/efeitos dos fármacos
8.
J Sep Sci ; 40(7): 1470-1481, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28139096

RESUMO

Polyphenols derived from Danshen are responsible for the therapeutic effects of DanHong injection, a two-herb combination of Danshen and Honghua. Whether the pharmacokinetics of Danshen polyphenols is changed by coexisting Honghua constituents remains unknown. A sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed in this study for simultaneous determination of eight Danshen polyphenols (i.e., protocatechuic aldehyde, protocatechuic acid, tanshinol, salvianolic acid D, rosmarinic acid, salvianolic acid A, lithospermic acid, and salvianolic acid B) in rat plasma and applied to a comparative pharmacokinetic study of DanHong injection and Danshen injection. Liquid chromatography conditions, mass spectrometry parameters, and sample preparation were optimized step by step. The calibration curves showed good linearity (r > 0.99) for all the polyphenols. The mean extraction efficiencies ranged from 62.2 to 88.7% with negligible matrix effects. The intrabatch and interbatch precision at all the quality control levels were less than 15% of the nominal concentrations with accuracy of 88.8-114%, except that precision and accuracy at lower limit of quantitation were 3.2-17.3 and 95.7-119%, respectively. Comparative pharmacokinetic study suggested that the coexisting Honghua constituents might have negligible influences on the pharmacokinetics of Danshen polyphenols from DanHong injection. The bioanalytical method could also be applied to pharmacokinetic studies of other Danshen herbal products.


Assuntos
Análise Química do Sangue/métodos , Medicamentos de Ervas Chinesas/farmacocinética , Polifenóis/sangue , Salvia miltiorrhiza/química , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
9.
Drug Metab Pharmacokinet ; 31(1): 95-98, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26830081

RESUMO

XueBiJing injection, prepared from a five-herb combination, is extensively used as add-on therapy in routine sepsis care in China. Catechols, derived from the component herb Salvia miltiorrhiza roots (Danshen), are probably important because of their reported antiseptic properties. This study was designed to characterize pharmacokinetics of major circulating Danshen catechols in human subjects intravenously receiving the injection at the label doses. A total of 17 Danshen catechols were detected in XueBiJing injection (content level, 0.1-139.3 µmol/L). After dosing, tanshinol and salvianolic acid B exhibited relatively high levels of systemic exposure with mean elimination half-lives of 0.38 and 0.29 h, respectively. The total plasma clearance and apparent volume of distribution at steady state of tanshinol were 1.07 L/h/kg and 0.40 L/kg, respectively, whereas those of salvianolic acid B were 0.43 L/h/kg and 0.13 L/kg, respectively. Protocatechuic acid and five other catechols were also detected in plasma but at low exposure levels. Although protocatechuic aldehyde had the highest content level in the injection, like the remaining eight catechols, it was undetected in plasma. Protocatechuic aldehyde was extensively converted into protocatechuic acid and other metabolites. The information gained here facilitates understanding the roles of Danshen catechols in therapeutic actions of XueBiJing injection.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Catecóis/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Administração Intravenosa , Adulto , China , Feminino , Medicina Herbária/métodos , Humanos , Hidroxibenzoatos/administração & dosagem , Masculino , Fitoterapia/métodos , Extratos Vegetais/administração & dosagem , Salvia miltiorrhiza/química , Adulto Jovem
10.
Br J Pharmacol ; 172(4): 1059-73, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25297453

RESUMO

BACKGROUND AND PURPOSE: Ginsenosides are bioactive saponins derived from Panax notoginseng roots (Sanqi) and ginseng. Here, the molecular mechanisms governing differential pharmacokinetics of 20(S)-protopanaxatriol-type ginsenoside Rg1 , ginsenoside Re and notoginsenoside R1 and 20(S)-protopanaxadiol-type ginsenosides Rb1, Rc and Rd were elucidated. EXPERIMENTAL APPROACH: Interactions of ginsenosides with human and rat hepatobiliary transporters were characterized at the cellular and vesicular levels. A rifampin-based inhibition study in rats evaluated the in vivo role of organic anion-transporting polypeptide (Oatp)1b2. Plasma protein binding was assessed by equilibrium dialysis. Drug-drug interaction indices were calculated to estimate potential for clinically relevant ginsenoside-mediated interactions due to inhibition of human OATP1Bs. KEY RESULTS: All the ginsenosides were bound to human OATP1B3 and rat Oatp1b2 but only the 20(S)-protopanaxatriol-type ginsenosides were transported. Human multidrug resistance-associated protein (MRP)2/breast cancer resistance protein (BCRP)/bile salt export pump (BSEP)/multidrug resistance protein-1 and rat Mrp2/Bcrp/Bsep also mediated the transport of the 20(S)-protopanaxatriol-type ginsenosides. Glomerular-filtration-based renal excretion of the 20(S)-protopanaxatriol-type ginsenosides was greater than that of the 20(S)-protopanaxadiol-type counterparts due to differences in plasma protein binding. Rifampin-impaired hepatobiliary excretion of the 20(S)-protopanaxatriol-type ginsenosides was effectively compensated by the renal excretion in rats. The 20(S)-protopanaxadiol-type ginsenosides were potent inhibitors of OATP1B3. CONCLUSION AND IMPLICATIONS: Differences in hepatobiliary and in renal excretory clearances caused markedly different systemic exposure and different elimination kinetics between the two types of ginsenosides. Caution should be exercised with the long-circulating 20(S)-protopanaxadiol-type ginsenosides as they could induce hepatobiliary herb-drug interactions, particularly when patients receive long-term therapies with high-dose i.v. Sanqi or ginseng extracts.


Assuntos
Ginsenosídeos/farmacocinética , Interações Ervas-Drogas , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Proteínas Sanguíneas/metabolismo , Feminino , Células HEK293 , Humanos , Rim/metabolismo , Fígado/metabolismo , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Ratos Sprague-Dawley , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto
11.
Acta Pharmacol Sin ; 34(11): 1437-48, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24056706

RESUMO

AIM: To investigate the pharmacokinetics and disposition of simmitecan (L-P) that was a water-soluble ester prodrug of chimmitecan (L-2-Z) with potent anti-tumor activities in different experimental animals, and to assess its drug-drug interaction potential. METHODS: SD rats were injected with a single iv bolus doses of L-P (3.75, 7.5 and 15 mg/kg). The pharmacokinetics, tissue distribution, excretion and metabolism of L-P and its active metabolite L-2-Z were studied through quantitative measurements and metabolite profiling with LC/MS. The binding of L-P and L-2-Z to rat plasma proteins was examined using an ultrafiltration method. Systemic exposures of beagle dogs to L-P as well as drug distribution in tumors of the nude mice xenograft model of human hepatic cancer SMMC-7721 cells were also examined. The metabolism of L-P by liver mcirosomal carboxylesterase in vitro was investigated in different species. The effects of L-P and L-2-Z on cytochrome P450 enzymes were examined using commercial screening kits. RESULTS: The in vivo biotransformation of L-P to L-2-Z showed a significant species difference, with a mean elimination half-life t1/2 of approximately 1.4 h in rats and 1.9 h in dogs. The systemic exposure levels of L-P and L-2-Z were increased in a dose-dependent manner. In rats, approximately 66% of L-P and 79% of L-2-Z were bound to plasma proteins. In rats and the nude mice bearing human hepatic cancers, most organ tissues had significantly higher concentrations of L-P than the corresponding plasma levels. In the tumor tissues, the L-P levels were comparable to those of plasma, whereas the L-2-Z levels were lower than the L-P levels. In rats, L-P was eliminated mainly via biliary excretion, but metabolism played an important role in elimination of the intact L-P. Finally, L-P and L-2-Z exerted moderate inhibition on the activity of CYP3A4 in vitro. CONCLUSION: L-P and L-2-Z have relatively short elimination half-lives and L-P is mainly eliminated via biliary excretion. The species difference in the conversion of L-P to L-2-Z and potential drug-drug interactions due to inhibition of CYP3A4 should be considered in further studies.


Assuntos
Antineoplásicos/farmacocinética , Camptotecina/análogos & derivados , Inibidores Enzimáticos/farmacocinética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Camptotecina/farmacologia , Carboxilesterase/metabolismo , Citocromo P-450 CYP3A , Inibidores do Citocromo P-450 CYP3A , Cães , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Feminino , Meia-Vida , Humanos , Injeções Intravenosas , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Camundongos , Camundongos Nus , Microssomos Hepáticos/metabolismo , Pró-Fármacos , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Br J Pharmacol ; 170(2): 440-57, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23808355

RESUMO

BACKGROUND AND PURPOSE: Flavonols and terpene lactones are putatively responsible for the properties of Ginkgo biloba leaf extracts that relate to prevention and treatment of cardiovascular disease and cerebral insufficiency. Here, we characterized rat systemic and cerebral exposure to these ginkgo compounds after dosing, as well as the compounds' pharmacokinetics. EXPERIMENTAL APPROACH: Rats received single or multiple doses of ShuXueNing injection (prepared from GBE50 for intravenous administration) or GBE50 (a standardized extract of G. biloba leaves for oral administration). Brain delivery of the ginkgo compounds was assessed with microdialysis. Various rat samples were analysed using liquid chromatography/mass spectrometry. KEY RESULTS: Slow terminal elimination features of the flavonols counterbalanced the influence of poor oral bioavailability on their systemic exposure levels, which also resulted in significant accumulation of the compounds in plasma during the subchronic treatment with ShuXueNing injection and GBE50. Unlike the flavonols, the terpene lactones had poor enterohepatic circulation due to their rapid renal excretion and unknown metabolism. The flavonol glycosides occurred as major forms in plasma after dosing with ShuXueNing injection, while the flavonol aglycone conjugates were predominant in plasma after dosing with GBE50. Cerebral exposure was negligible for the flavonols and low for the terpene lactones. CONCLUSION AND IMPLICATIONS: Unlike the significant systemic exposure levels, the levels of cerebral exposure to the flavonols and terpene lactones are low. The elimination kinetic differences between the two classes of ginkgo compounds influence their relative systemic exposure levels. The information gained is relevant to linking ginkgo administration to the medicinal effects.


Assuntos
Flavonóis/farmacocinética , Ginkgo biloba/química , Lactonas/farmacocinética , Terpenos/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Encéfalo/metabolismo , Cromatografia Líquida , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Flavonóis/administração & dosagem , Flavonóis/isolamento & purificação , Glicosídeos/administração & dosagem , Glicosídeos/farmacocinética , Lactonas/administração & dosagem , Lactonas/isolamento & purificação , Masculino , Espectrometria de Massas , Microdiálise , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Folhas de Planta , Ratos , Ratos Sprague-Dawley , Terpenos/administração & dosagem , Terpenos/isolamento & purificação , Distribuição Tecidual
13.
Science ; 333(6047): 1303-7, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21817016

RESUMO

The prevalent DNA modification in higher organisms is the methylation of cytosine to 5-methylcytosine (5mC), which is partially converted to 5-hydroxymethylcytosine (5hmC) by the Tet (ten eleven translocation) family of dioxygenases. Despite their importance in epigenetic regulation, it is unclear how these cytosine modifications are reversed. Here, we demonstrate that 5mC and 5hmC in DNA are oxidized to 5-carboxylcytosine (5caC) by Tet dioxygenases in vitro and in cultured cells. 5caC is specifically recognized and excised by thymine-DNA glycosylase (TDG). Depletion of TDG in mouse embyronic stem cells leads to accumulation of 5caC to a readily detectable level. These data suggest that oxidation of 5mC by Tet proteins followed by TDG-mediated base excision of 5caC constitutes a pathway for active DNA demethylation.


Assuntos
Citosina/análogos & derivados , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Timina DNA Glicosilase/metabolismo , 5-Metilcitosina/metabolismo , Animais , Linhagem Celular , Citosina/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/genética , Dioxigenases , Células-Tronco Embrionárias , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Oxirredução , Proteínas Proto-Oncogênicas/genética , RNA Interferente Pequeno , Timina DNA Glicosilase/genética , Transfecção
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