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1.
Analyst ; 139(2): 505-16, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24286102

RESUMO

Over recent decades sulfur fumigation has been becoming abused in processing some freshly harvested Chinese medicinal herbs, although it is questioned whether sulfur fumigation can result in changes in efficacy and safety of the herbs. One of the herbs commonly processed by sulfur fumigation is Codonopsis Radix (Dangshen). A report showed that lobetyolin content in sulfur-fumigated Dangshen was lower than in air-dried Dangshen. Whereas there is no investigation designed to compare the chemical profiles of the sulfur-fumigated Dangshen and the air-dried Dangshen. In the present study, a rapid and versatile ultra-high-performance liquid chromatography coupled with ultra-high resolution quadrupole time-of-flight mass spectrometry (UHPLC UHD Q-TOF MS/MS) method was developed for comprehensive analysis of the chemical profiles of sulfur-fumigated and air-dried Dangshen samples. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) demonstrated that there were significant chemical differences between sulfur-fumigated and air-dried Dangshen samples. Among the changed components, 57 compounds were identified, in which 15 sulfur-containing compounds were detected only in sulfur-fumigated samples. The established methods were successfully applied to discriminate sulfur-fumigated Dangshen among commercial samples. Whether the chemical changes caused by sulfur fumigation affect the clinical efficacy and safety of Dangshen needs to be further investigated.


Assuntos
Codonopsis/química , Fumigação , Enxofre/química , Espectrometria de Massas em Tandem , Ar , Cromatografia Líquida de Alta Pressão , Controle de Qualidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-26229546

RESUMO

Coptis chinensis rhizomes (CR) are one important ingredient of traditional Chinese herbal formulas such as San-Huang-Xie-Xin-Tang which is used for treatment of cardiovascular and neurodegenerative diseases. Recent studies suggest that the extract of CR might be a potential therapeutic agent for amelioration of neurological disorders associated with oxidative stress. In the present study we aimed at revealing the main active compound(s) of the CR extract and at investigating the mechanism of action. Four main alkaloids of the CR extract (berberine, coptisine, jatrorrhizine, and palmatine) were selected for this study. Results showed that out of those alkaloids only pretreatment with coptisine significantly attenuated tert-butylhydroperoxide induced reduction of cell viability, increased rate of apoptosis, and declined mitochondrial membrane potential. Elisa assay and quantitative real-time PCR analyses revealed that thioredoxin-interacting protein (TXNIP) gene expression was downregulated by coptisine, which could explain the neuroprotective effect, hypothetically, by strengthening the thioredoxin defense system against oxidative stress and attenuation of apoptosis signal-regulating kinase (Ask1) mediated apoptotic signaling. A comparison between coptisine and CR extract identified coptisine as the main single component responsible for the neuroprotective effect. Based on the results the CR extract and coptisine are promising candidate agents for prevention or improvement of diabetic neuropathy and neurodegenerative disorders.

3.
J Ethnopharmacol ; 155(1): 607-15, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-24929105

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The dried rhizome of Coptis chinensis Franch. (family Ranunculaceae) is traditionally used in Chinese medicine for the treatment of inflammatory diseases and diabetes. Recent studies showed a variety of activities of Coptis chinensis Franch. alkaloids, including neuroprotective, neuroregenerative, anti-diabetic, anti-oxidative and anti-inflammatory effects. However, there is no report on the neuroprotective effect of Coptis chinensis Franch. watery extract against tert-butylhydroperoxide (t-BOOH) induced oxidative damage. The aim of the study is to investigate neuroprotective properties of Coptis chinensis Franch. rhizome watery extract (CRE) and to evaluate its potential mechanism of action. MATERIALS AND METHODS: Neuroprotective properties on t-BOOH induced oxidative stress were investigated in SH-SY5Y human neuroblastoma cells. Cells were pretreated with CRE for 2 h or 24 h followed by 2 h of treatment with t-BOOH. To evaluate the neuroprotective effect of CRE, cell viability, cellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and the apoptotic rate were determined and microarray analyses, as well as qRT-PCR analyses were conducted. RESULTS: Two hours of exposure to 100 µM t-BOOH resulted in a significant reduction of cell viability, increased apoptotic rate, declined mitochondrial membrane potential (MMP) and increased ROS production. Reduction of cell viability, increased apoptotic rate and declined mitochondrial membrane potential (MMP) could be significantly reduced in cells pretreated with CRE (100 µg/ml) for 2h or 24h ahead of t-BOOH exposure with the greatest effect after 24h of pretreatment; however ROS production was not changed significantly. Furthermore, microarray analyses revealed that the expressions of 2 genes; thioredoxin-interacting protein (TXNIP) and mitochondrially encoded NADH dehydrogenase 1, were significantly regulated. Down regulation of TXNIP was confirmed by qRT-PCR. CONCLUSION: Due to its neuroprotective properties CRE might be a potential therapeutic agent for the prevention or amelioration of diseases like diabetic neuropathy and neurodegenerative disorders like Alzheimer and Parkinsons disease.


Assuntos
Coptis/química , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Análise em Microsséries , Neuroblastoma/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/isolamento & purificação , Extratos Vegetais/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rizoma , Fatores de Tempo , terc-Butil Hidroperóxido/toxicidade
4.
J Ethnopharmacol ; 156: 365-9, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25278181

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Although slightly toxic, the Chinese medicinal herb Herba Siegesbeckiae (HS) has long been used as a remedy for traditional Chinese medicine symptoms that resemble inflammatory joint disorders, because it can eliminate the wind-dampness and soothe painful joints. Proper processing can reduce the toxicity and/or enhance the efficacy of raw herbs. In this study, we aim to examine if processing with rice wine reduces the cytotoxicities and/or enhances the anti-inflammatory effects of HS, and to explore the chemical basis behind the potential changes of medicinal properties caused by the processing. MATERIALS AND METHODS: We used cell models to examine the cytotoxicities and anti-inflammatory effects of HS and rice wine-processed HS (WHS). The chemical profiles of HS and WHS were compared using the ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS) analysis. RESULTS: We found that WHS was less toxic than HS in cultured cells as shown in the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Both HS and WHS had anti-inflammatory effects as demonstrated by their abilities to reduce nitric oxide (NO) production as well as protein and mRNA expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Interestingly, the anti-inflammatory effects of WHS were more potent than that of HS at the concentration of 100 µg/mL. By comparing the chemical profiles, we found that 19 peaks were lower, while 2 other peaks were higher in WHS than in HS. Four compounds including neo-darutoside, darutoside, stigmasterol and 16-O-acetyldarutoside corresponding to 4 individual changed peaks were tentatively identified by matching with empirical molecular formulae and mass fragments. CONCLUSION: Our study showed that processing with rice wine significantly reduced the cytotoxicities and enhanced the anti-inflammatory effects of HS as demonstrated in cell models. We also developed a UPLC/Q-TOF-MS method to clearly differentiate HS from WHS by their different chemical profiles. Further study is warranted to establish the relationship between the alteration of chemical profiles and the changes of medicinal properties caused by processing with rice wine.


Assuntos
Anti-Inflamatórios/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Diterpenos/farmacologia , Células HEK293 , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Medicina Tradicional Chinesa/métodos , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Oryza , Estigmasterol/farmacologia , Vinho
5.
J Ethnopharmacol ; 141(2): 622-8, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21903156

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Qian-wang-hong-bai-san (QW), a Chinese herbal formula, is traditionally used as a skin whitening agent in China. AIM OF STUDY: In our previous screening assays, QW was identified as an effective tyrosinase inhibitor. In this study, we aim to investigate the underlying mechanism of the anti-melanogenic effect of QW in B16 cells. MATERIALS AND METHODS: Cytotoxicity of QW in B16 cell line was examined by MTT assay. Cellular tyrosinase activity was determined based on the melanin content measured at 475 nm with a microplate spectrophotometer. Protein expression was analyzed by Western blotting and quantified by Quantity One. RESULTS: QW dose-dependently inhibited tyrosinase activity and decreased melanin content at 48 h without significant cytotoxicity in B16 cells. Western blot analysis showed that QW treatment down-regulated the expression levels of phospho-p38, phospho-CREB, MITF, tyrosinase, TRP-1 and TRP-2 in a dose-dependent manner. At the same time, QW treatment for 48 h inhibited IBMX-induced elevation of cellular melanin content and tyrosinase activity. However, the attenuation of IBMX-mediated up-regulations of phospho-CREB and phospho-PKA was readily observed with 60 min of QW treatment. CONCLUSIONS: The anti-melanogenic activity of QW in B16 melanoma cells can be attributed, at least in part, to the inhibition of the p38 MAPK and PKA signaling pathways. These findings shed new light on the molecular mechanisms of the skin-whitening property of QW.


Assuntos
Clareadores/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Medicamentos de Ervas Chinesas/farmacologia , Melaninas/biossíntese , Melanoma Experimental/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Western Blotting , Linhagem Celular Tumoral , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Oxirredutases Intramoleculares/metabolismo , Medicina Tradicional Chinesa , Melanoma Experimental/patologia , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Oxirredutases/metabolismo , Fosforilação , Plantas Medicinais , Pigmentação da Pele/efeitos dos fármacos , Espectrofotometria , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
J Ethnopharmacol ; 132(2): 533-5, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20837127

RESUMO

AIM OF THE STUDY: San-bai-tang (SBT), a Chinese herbal formula, is traditionally used as a skin whitener in China. In our previous screening assays, SBT was identified as an effective tyrosinase inhibitor. In this study, we aim to investigate the anti-melanogenic effect and mechanisms of SBT in B16 cells. MATERIALS AND METHODS: Cell viability was examined by the MTT assay. Cellular tyrosinase activity and melanin content were determined using spectrophotographic methods. Protein expression was analyzed by immunoblotting. RESULTS: SBT inhibited tyrosinase activity with an IC(50) of 215.6 ± 10.3 µg/ml, and decreased cellular melanin content with an IC(50) of 254.8 ± 14.5 µg/ml at 48 h. MTT assay demonstrated that 48-h SBT (50-400 µg/ml) treatment did not show obvious cytotoxicity. Immunoblot analysis showed that SBT (100, 200 or 400 µg/ml) treatment for 48 h down-regulated the expression levels of phosphorylated-p38, MITF, tyrosinase, TRP-1 and TRP-2 in a dose-dependent manner. CONCLUSIONS: SBT inhibited melanogenesis in B16 cells, and suppression of p38 MAPK signaling pathway contributed to the anti-melanogenic effect of SBT by down-regulating the expression of MITF and melanogenic enzymes. These novel findings demonstrated the anti-melanogenic effect and mechanisms of SBT, and provide pharmacological basis for the traditional use of SBT.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Sistema de Sinalização das MAP Quinases , Melaninas/biossíntese , Monofenol Mono-Oxigenase/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Atractylodes , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Humanos , Melaninas/genética , Melaninas/metabolismo , Melanoma Experimental , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Paeonia , Fitoterapia , Smilax , Proteínas Quinases p38 Ativadas por Mitógeno/genética
7.
J Ethnopharmacol ; 129(3): 387-90, 2010 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-20430091

RESUMO

AIM OF THE STUDY: Tyrosinase inhibitors are becoming increasingly important in controlling skin hyperpigmentation. We aimed to screen 50 extracts from traditional Chinese medicines (TCM) for tyrosinase activity-inhibiting agents. MATERIALS AND METHODS: The 50 herbal extracts were prepared from 32 herbs and 18 TCM formulas, which are used as folk skin whiteners in China and have not been investigated for their skin-whitening mechanisms. Each herb and formula was extracted with 30% ethanol and water, respectively, and followed by column chromatography for isolating bioactive substances such as saponins, flavonoids and alkaloids for the antityrosinase activity study. Every extract was tested using the cell free mushroom tyrosinase inhibitory assay at 2 mg/ml for the single herb extracts and 1mg/ml for formula extracts. Extracts showing greater than 50% inhibition against mushroom tyrosinase activity were further examined by cellular tyrosinase assay in mouse B16 cells. The cytotoxicity in B16 cells was measured by methyl thiazolyl tetrazolium bromide (MTT) assay. RESULTS: In the cell-free assay, 10 out of the 50 extracts demonstrated more than 50% inhibition against mushroom tyrosinase activity. These 10 extracts were further assessed by cellular tyrosinase assay, and 6 showed>50% inhibition with IC(50) values <1 mg/ml. The 6 extracts are from 3 herbs namely Ampelopsis japonica, Lindera aggregata, and Polygonatum odoratum, and 3 formulas namely Qian-wang-hong-bai-san, Qiong-yu-gao, and San-bai-tang. As compared with vitamin C, these 6 extracts showed similar or greater ratio of cell growth IC(50) to cellular tyrosinase IC(50). As compared with arbutin, extract from Ampelopsis japonica, Lindera aggregata, Qian-wang-hong-bai-san, or San-bai-tang had a similar, although extract from Polygonatum odoratum or Qiong-yu-gao had a greater, IC(50) value against murine tyrosinase activity. CONCLUSIONS: From the screening assays we identified three Chinese medicinal herbs and three TCM formulas that have appreciable antityrosinase activity. Further studies are warranted to develop them as skin-whitening agents with convenient dosage forms or to identify active constituents from the extracts as useful leads for the development of skin whiteners.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Medicina Tradicional Chinesa , Camundongos , Pigmentação da Pele/efeitos dos fármacos , Espectrofotometria
8.
Forsch Komplementmed ; 17(4): 209-13, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20829599

RESUMO

AIM: Recently, we have demonstrated that silymarin has a comparable pharmaceutical activity as Phyllanthus urinaria extract when used to rescue mice from acetaminophen-induced acute liver injury. In the present study, we further compared the therapeutic action of silymarin with N-acetyl cysteine (commonly used in clinical practice for emergency treatments) as a rescuer in mice after administering a lethal dose of acetaminophen for 24 h. METHODS: Acute liver injury was induced in the treatment groups by intraperitoneally administered acetaminophen at a dose of 550 mg/kg body weight on day 1. The control group received an equal volume of physiological saline intraperitoneally. From day 2 to 4, the treatment groups received various doses of silymarin or N-acetyl cysteine orally once daily, while the control group and the acetaminophen group received an equal volume of water orally. The mortality rate was recorded in all groups. On day 5, all mice were sacrificed for examination. RESULTS: Silymarin greatly improved the counteracting effects on mortality rate as compared to N-acetyl cysteine. CONCLUSION: Silymarin should be further considered as an antidote for patients with acetaminopheninduced acute hepatic injury and delayed treatment.


Assuntos
Acetaminofen/toxicidade , Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Silimarina/uso terapêutico , Alanina Transaminase/efeitos dos fármacos , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/efeitos dos fármacos , Aspartato Aminotransferases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL
9.
Phytomedicine ; 18(1): 11-5, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21036022

RESUMO

We have investigated the potential in vivo anti-tumour activity of corilagin using the Hep3B hepatocellular carcinoma cell line and an athymic nude mice xenograft model. The purity of corilagin was confirmed by high performance liquid chromatographic analysis. Corilagin was administrated intraperitoneally for a continuous period of 7 days at a concentration of 15 mg/kg of body weight per day. A significant inhibition of tumour growth was observed when treated mice are compared with control groups. Furthermore, analysis of enzymes markers of liver function, including alanine aminotransferase and asparate aminotransferase, suggested that current therapeutic dosage of corilagin did not exert adverse effect on liver. Our observations support the view that corilagin is considerably effective to retard the in vivo growth of xenografted Hep3B hepatocellular carcinoma.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Glucosídeos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Glucosídeos/administração & dosagem , Glucosídeos/farmacologia , Humanos , Taninos Hidrolisáveis , Fígado/efeitos dos fármacos , Fígado/enzimologia , Camundongos , Camundongos Nus , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Phytomedicine ; 16(8): 751-60, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19386480

RESUMO

Acetaminophen is a commonly used drug for the treatment of patients with common cold and influenza. However, an overdose of acetaminophen may be fatal. In this study we investigated whether mice, administered intraperitoneally with a lethal dose of acetaminophen, when followed by oral administration of Phyllanthus urinaria extract, may be prevented from death. Histopathological analysis of mouse liver sections showed that Phyllanthus urinaria extract may protect the hepatocytes from acetaminophen-induced necrosis. Therapeutic dose of Phyllanthus urinaria extract did not show any toxicological phenomenon on mice. Immunohistochemical staining with the cytochrome P450 CYP2E1 antibody revealed that Phyllanthus urinaria extract reduced the cytochrome P450 CYP2E1 protein level in mice pre-treated with a lethal dose of acetaminophen. Phyllanthus urinaria extract also inhibited the cytochrome P450 CYP2E1 enzymatic activity in vitro. Heavy metals, including arsenic, cadmium, mercury and lead, as well as herbicide residues were not found above their detection limits. High performance liquid chromatography identified corilagin and gallic acid as the major components of the Phyllanthus urinaria extract. We conclude that Phyllanthus urinaria extract is effective in attenuating the acetaminophen induced hepatotoxicity, and inhibition of cytochrome P450 CYP2E1 enzyme may be an important factor for its therapeutic mechanism.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Inibidores do Citocromo P-450 CYP2E1 , Fígado/metabolismo , Phyllanthus , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Doença Hepática Induzida por Substâncias e Drogas/mortalidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Ácido Gálico/isolamento & purificação , Ácido Gálico/farmacologia , Ácido Gálico/uso terapêutico , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Hepatócitos/efeitos dos fármacos , Taninos Hidrolisáveis , Fígado/patologia , Metais Pesados/análise , Camundongos , Camundongos Endogâmicos C57BL , Necrose/tratamento farmacológico , Phyllanthus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química
11.
Acc Chem Res ; 36(4): 276-83, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12693925

RESUMO

Since 1989, wavelet transform (WT) has attracted much interest of chemists working on signal and image processing, and the WT-based techniques have been successfully applied to the chemical signal processing. This approach has been demonstrated as fast in computation with localization and having quick decay properties, in contrast to the popular methods existing, especially to the fast Fourier transform. More than 370 papers have been published up to the year 2002 which covered applications of WT in various fields of chemistry, including analytical chemistry, chemical physics, and quantum chemistry. In this paper, we report on applications of WT to data compression, data smoothing and denoising, baseline and background correction, resolution of multicomponent overlapping signals, regression and classification, and analytical images processing in analytical chemistry. Through this report we wish to induce greater interest of chemists in WT and to obtain greater benefits from using the WT-based techniques.

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