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1.
J Ethnopharmacol ; 237: 20-27, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30880257

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The whole plant of Glycine tabacina (Labill.) Benth has been used as a traditional herbal medicine to treat rheumatism, ostealgia and nephritis in China. It is also one of the sources of the renowned native herbal medicine 'I-Tiao-Gung' in Taiwan. AIM OF THE STUDY: This study aimed to investigate the anti-arthritic effect of ethanol extract of G. tabacina (GTE) in a collagen-induced arthritis (CIA) rat model. MATERIALS AND METHODS: The chemical profile of GTE was analyzed by HPLC-UV. The CIA was induced in male Wistar rats by intradermal injection of bovine type II collagen at tail root, back and ankle joints. The rats were orally administrated daily with GTE (1.11, 2.22 and 4.44 g dry weight of herb powder per kg body weight) from day 0 and continued for 30 days. Swelling volume and thickness of paw, arthritis index, X-radiographs and histopathological changes were examined to assess the severity of arthritis. Furthermore, the levels of pro-inflammatory cytokines, such as interleukin1ß (IL-1ß), IL-6 and tumor necrosis factor α (TNF-α), total superoxide dismutase (T-SOD) activity and malonaldehyde (MDA) level were measured to preliminarily explore the possible mechanisms. RESULTS: Oral administration of GTE significantly ameliorated the arthritic symptoms in CIA rat model, as indicated by the effects on paws swelling and arthritis index. X-radiographic analysis and histopathological examinations demonstrated that GTE effectively protected the bone and cartilage of joints from erosion, lesion and deformation. The efficacy of GTE treatment on CIA was comparable to that of indomethacin (positive drug). Besides, the overproduction of IL-1ß, IL-6 and TNF-α was remarkably inhibited in the serum of all GTE treatment groups. The restoration of serum T-SOD activity and MDA level proved that GTE administration alleviated the oxidative stress in CIA rats. CONCLUSIONS: GTE exhibited strong anti-CIA activity through inhibiting pro-inflammatory cytokines and oxidation in rats, suggesting its potential preventive and therapeutic effects on rheumatoid arthritis (RA).


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite Experimental/tratamento farmacológico , Fabaceae , Extratos Vegetais/uso terapêutico , Animais , Articulação do Tornozelo/efeitos dos fármacos , Articulação do Tornozelo/patologia , Anti-Inflamatórios/farmacologia , Artrite Experimental/imunologia , Artrite Experimental/patologia , Citocinas/sangue , Articulação do Joelho/efeitos dos fármacos , Articulação do Joelho/patologia , Masculino , Malondialdeído/sangue , Oxirredução , Fitoterapia , Extratos Vegetais/farmacologia , Ratos Wistar , Superóxido Dismutase/sangue
2.
Biochim Biophys Acta Gen Subj ; 1862(8): 1751-1759, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29763643

RESUMO

BACKGROUND: Polysaccharides, one of the active ingredients in herbal medicine, are proved to enhance innate immunity against infections. The aim of this study is to explore the immunoregulatory ability of polysaccharides from Rhynchosia minima root in vitro and in vivo. METHODS: Polysaccharide fractions of R. minima root were obtained by chromatographic column. The content of NO was measured by spectrophotometry. The levels of cytokines (tumor necrosis factor-α, TNF-α; interleukin-6, IL-6; and monocyte chemoattractant protein-1, MCP-1) were determined by enzyme-linked immuno-sorbent assay (ELISA) kits. The translocation of p65 into the nucleus was imaged by confocal microscopy. The mRNA expression of TNF-α, IL-6, and MCP-1 was determined by quantitative real-time PCR. T-lymphocyte subgroups of spleen from immunosuppressive mouse were evaluated by flow cytometry. RESULTS: PRM3 remarkably enhanced the phagocytic ability of macrophages and promoted the release of NO and the secretion of cytokines (TNF-α, IL-6, and MCP-1) from macrophages. Simultaneously, PRM3 potently activated NF-κB signaling pathway via Toll-like receptor 4 (TLR4). In addition, PRM3 obviously increased the levels of serum cytokines, markedly up-regulated the percentages of CD3+ and CD4+ T lymphocytes and the CD4+/CD8+ ratio of splenocytes, and effectively attenuated cyclophosphamide induced immunosuppression in mice. CONCLUSIONS: PRM3 profoundly enhanced the immune function in vitro and in vivo through TLR4-NF-κB pathway and is a promising candidate of immunopotentiator which could be applied in functional foods or drugs. GENERAL SIGNIFICANCE: This study reported a polysaccharide PRM3 from R. minima root exhibited potent immunoenhancing activity and significantly alleviated cyclophosphamide-induced immunosuppression through TLR4-NF-κB pathway.


Assuntos
Fabaceae/química , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos/imunologia , NF-kappa B/metabolismo , Raízes de Plantas/química , Polissacarídeos/farmacologia , Receptor 4 Toll-Like/metabolismo , Animais , Células Cultivadas , Citocinas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos
3.
J Pharm Biomed Anal ; 154: 312-320, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29567574

RESUMO

An herb commonly contains hundreds of constituents. Identification of bioactive compound(s) in each herb using conventional approaches is usually inefficient and eco-unfriendly. In this study, we aimed to fast identify anticancer compounds in Forsythiae Fructus using UPLC/MS-based metabolomics analysis. We firstly fractionated Forsythiae Fructus crude extracts with organic solvents of different polarity, then the chemical profile of each fraction was analyzed by UPLC/Q-TOF/MS, and the anticancer activity profiles of all fractions were determined by MTT assay. Next, orthogonal projections to latent structures discriminant analysis (OPLS-DA) was applied to discriminate fractions with different anticancer activity to determine the compound(s) that contributes most to the anticancer activity. Betulinic acid was then identified to be the most potent anticancer compound in Forsythiae Fructus. Its predicted anticancer activity was confirmed by MTT assay. Taken together, our results demonstrated that the present integrated metabolomics strategy could be used for fast identification of anticancer compound(s) in herb extracts or other complex mixtures of chemicals.


Assuntos
Antineoplásicos/análise , Antineoplásicos/química , Forsythia/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Análise Discriminante , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Frutas/química , Melanoma Experimental , Metabolômica/métodos , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem/métodos
4.
Am J Chin Med ; 45(7): 1513-1536, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28946767

RESUMO

Forsythiae Fructus, Lianqiao in Chinese, is one of the most fundamental herbs in Traditional Chinese Medicine. Both green Forsythia (GF) and ripe Forsythia (RF) are referred to Forsythiae Fructus in medicinal applications. In most cases, they are used without distinction. In this study, a metabolomics approach was performed to compare componential differences of two Forsythiae Fructus aqueous extracts subtypes. Principal component analysis (PCA) score plots from the UPLC-MS data showed clear separation between the two subtypes, indicating there are significant differences in the chemical components between GF and RF. Meanwhile, the anticancer activity of them was also compared. GF exhibited much stronger antitumor activity than RF against B16-F10 murine melanoma both in vitro and in vivo. 15 chemical compounds were identified as specific markers for distinguishing GF and RF. Among these marker compounds, forsythoside I, forsythoside A, forsythoside E and pinoresinol were demonstrated to be key important active compounds that account for the different anticancer efficacies of GF and RF. Our data suggest that GF and RF should be distinctively used in clinical applications, particularly in the anticancer formulas, in which GF should be preferentially prescribed.


Assuntos
Antineoplásicos Fitogênicos , Forsythia/química , Frutas/química , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Fitoterapia , Extratos Vegetais/química , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Animais , Catecóis/isolamento & purificação , Catecóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Dissacarídeos/isolamento & purificação , Dissacarídeos/farmacologia , Feminino , Forsythia/classificação , Furanos/isolamento & purificação , Furanos/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Lignanas/isolamento & purificação , Lignanas/farmacologia , Espectrometria de Massas/métodos , Metabolômica , Camundongos Endogâmicos C57BL , Extratos Vegetais/classificação , Células Tumorais Cultivadas , Água
5.
Chin Med ; 12: 20, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28702078

RESUMO

In traditional Chinese medicine (TCM) theory, pathogenic heat and toxins, which are akin to the inflammatory factors, are the causes of cancer and could promote its virulent development. Therefore, heat-clearing and detoxicating (HCD) herbs are essential components of TCM formulas for cancer treatment. An increasing interest has been focused on the study of HCD herbs and accumulated evidences have shown that HCD herbs or HCD herbs-based formulas exhibited remarkable anticancer effects when used alone or combined with other therapeutic approaches. Some of the HCD herb-derived products have been tested in clinical trials. Studies revealed that extracts or pure compounds of the HCD herbs showed a broad anticancer spectrum against both solid and hematologic malignancies without significant toxic effects. Notably, some HCD herbs or formulas could strongly enhance the anticancer activities of chemo- or radio-therapy and alleviate their side effects. The anticancer activities of HCD herb exacts or the pure compounds were reported to be through multiple cellular or molecular mechanisms, such as induction of cancer cell apoptosis, differentiation and cell cycle arrest, inhibition of cancer cell growth, invasion and metastasis, and inhibition of tumor angiogenesis. In this review, we provide comprehensive analysis and summary of research progress and future prospects in this field to facilitate the further study and application of HCD herbs.

6.
Nat Prod Res ; 31(13): 1561-1565, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28135850

RESUMO

Two new flavans, named (2S)-2',4'-dihydroxy-7-methoxy-8-methylflavan (1) and (2S)-2'-hydroxy-4',7-dimethoxy-8-methylflavan (2) were isolated from the roots of Dianella ensifolia. Their structures were elucidated by extensive spectroscopic measurements and comparison with data reported in literatures. Compounds 1 and 2 displayed cytotoxic effects against cancer cell lines MDA-MB-231, B16-F10, HCT116 and A549.


Assuntos
Flavonoides/farmacologia , Magnoliopsida/química , Raízes de Plantas/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular
7.
Sci Rep ; 7: 41082, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28112228

RESUMO

Hormesis is an adaptive response of living organisms to a moderate stress. However, its biomedical implication and molecular mechanisms remain to be intensively investigated. Panaxatriol saponins (PTS) is the major bioactive components extracted from Panax notoginseng, a widely used herbal medicine for cerebrovascular diseases. This study aims to examine the hormetic and neuroprotective effects of PTS in PC12 cells and zebrafish Parkinson's disease (PD) models. Our results demonstrated that PTS stimulated PC12 cell growth by about 30% at low doses, while PTS at high doses inhibited cell growth, which is a typical hormetic effect. Moreover, we found that low dose PTS pretreatment significantly attenuated 6-OHDA-induced cytotoxicity and up-regulated PI3K/AKT/mTOR cell proliferation pathway and AMPK/SIRT1/FOXO3 cell survival pathway in PC12 cells. These results strongly suggested that neuroprotective effects of PTS may be attributable to the hormetic effect induced by PTS through activating adaptive response-related signaling pathways. Notably, low dose PTS could significantly prevent the 6-OHDA-induced dopaminergic neuron loss and improve the behavior movement deficiency in zebrafish, whereas relative high dose PTS exhibited neural toxicity, further supporting the hormetic and neuroprotective effects of PTS. This study indicates that PTS may have the potential in the development of future therapeutic medicines for PD.


Assuntos
Ginsenosídeos/administração & dosagem , Hormese/efeitos dos fármacos , Saponinas/administração & dosagem , Peixe-Zebra/genética , Quinases Proteína-Quinases Ativadas por AMP , Animais , Proteína Forkhead Box O3/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/química , Hormese/genética , Neuroproteção/efeitos dos fármacos , Células PC12 , Panax notoginseng/química , Fosfatidilinositol 3-Quinases/genética , Proteínas Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Saponinas/química , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/genética , Serina-Treonina Quinases TOR/genética
8.
Redox Biol ; 11: 1-11, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27835779

RESUMO

Berberine (BBR) is a renowned natural compound that exhibits potent neuroprotective activities. However, the cellular and molecular mechanisms are still unclear. Hormesis is an adaptive mechanism generally activated by mild oxidative stress to protect the cells from further damage. Many phytochemicals have been shown to induce hormesis. This study aims to investigate whether the neuroprotective activity of BBR is mediated by hormesis and the related signaling pathways in 6-OHDA-induced PC12 cells and zebrafish neurotoxic models. Our results demonstrated that BBR induced a typical hormetic response in PC12 cells, i.e. low dose BBR significantly increased the cell viability, while high dose BBR inhibited the cell viability. Moreover, low dose BBR protected the PC12 cells from 6-OHDA-induced cytotoxicity and apoptosis, whereas relatively high dose BBR did not show neuroprotective activity. The hormetic and neuroprotective effects of BBR were confirmed to be mediated by up-regulated PI3K/AKT/Bcl-2 cell survival and Nrf2/HO-1 antioxidative signaling pathways. In addition, low dose BBR markedly mitigated the 6-OHDA-induced dopaminergic neuron loss and behavior movement deficiency in zebrafish, while high dose BBR only slightly exhibited neuroprotective activities. These results strongly suggested that the neuroprotection of BBR were attributable to the hormetic mechanisms via activating cell survival and antioxidative signaling pathways.


Assuntos
Antioxidantes/administração & dosagem , Berberina/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Doença de Parkinson Secundária/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Heme Oxigenase-1/genética , Hormese/efeitos dos fármacos , Hormese/genética , Humanos , Fator 2 Relacionado a NF-E2/genética , Proteína Oncogênica v-akt/genética , Oxidopamina/toxicidade , Células PC12 , Doença de Parkinson Secundária/genética , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Peixe-Zebra
9.
Sci Rep ; 6: 26064, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27263652

RESUMO

Curcumin (CUR) and berberine (BBR) are renowned natural compounds that exhibit potent anticancer activities through distinct molecular mechanisms. However, the anticancer capacity of either CUR or BBR is limited. This prompted us to investigate the chemopreventive potential of co-treatment of CUR and BBR against breast cancers. The results showed that CUR and BBR in combination synergistically inhibited the growth of both MCF-7 and MDA-MB-231 breast cancer cells than the compounds used alone. Further study confirmed that synergistic anti-breast cancer activities of co-treatment of these two compounds was through inducing more apoptosis and autophagic cell death (ACD). The co-treatment-induced apoptosis was caspase-dependent and through activating ERK pathways. Our data also demonstrated that co-treatment of CUR and BBR strongly up-regulated phosphorylation of JNK and Beclin1, and decreased phosphorylated Bcl-2. Inhibition of JNK by SP600125 markedly decreased LC3-II and Beclin1, restored phosphorylated Bcl-2, and reduced the cytotoxicity induced by the two compounds in combination. These results strongly suggested that JNK/Bcl-2/Beclin1 pathway played a key role in the induction of ACD in breast cancer cells by co-treatment of CUR and BBR. This study provides an insight into the potential application of curcumin and berberine in combination for the chemoprevention and treatment of breast cancers.


Assuntos
Berberina/farmacologia , Neoplasias da Mama/tratamento farmacológico , Curcumina/farmacologia , Antineoplásicos Fitogênicos , Apoptose , Autofagia , Proteína Beclina-1/metabolismo , Processos de Crescimento Celular/efeitos dos fármacos , Quimioprevenção , Sinergismo Farmacológico , Humanos , MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células MCF-7 , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
10.
Planta Med ; 82(4): 305-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26669678

RESUMO

Rhizoma Coptidis, Cortex Phellodendri, and berberine were reported to inhibit Helicobacter pylori. However, the underlying mechanism remained elusive. Urease plays a vital role in H. pylori colonization and virulence. In this work, aqueous extracts of Rhizoma Coptidis, Cortex Phellodendri of different origins, and purified berberine were investigated against H. pylori urease and jack bean urease to elucidate the inhibitory capacity, kinetics, and mechanism. Results showed that berberine was the major chemical component in Rhizoma Coptidis and Cortex Phellodendri, and the content of berberine in Rhizoma Coptidis was higher than in Cortex Phellodendri. The IC50 values of Rhizoma Coptidis were significantly lower than those Cortex Phellodendri and purified berberine, of which Coptis chinensis was shown to be the most active concentration- and time-dependent urease inhibitor. The Lineweaver-Burk plot analysis indicated that the inhibition pattern of C. chinensis against urease was noncompetitive for both H. pylori urease and jack bean urease. Thiol protectors (L-cysteine, glutathione, and dithiothreithol) significantly protected urease from the loss of enzymatic activity, while fluoride and boric acid showed weaker protection, indicating the active-site sulfhydryl group was possibly responsible for its inhibition. Furthermore, the urease inhibition proved to be reversible since C. chinensis-blocked urease could be reactivated by glutathione. The results suggested that the anti-urease activity of Rhizoma Coptidis was superior to that of Cortex Phellodendri and berberine, which was believed to be more likely to correlate to the content of total alkaloids rather than berberine monomer. The concentration- and time-dependent, reversible, and noncompetitive inhibition against urease by C. chinensis might be attributed to its interaction with the sulfhydryl group of the active site of urease.


Assuntos
Coptis/química , Medicamentos de Ervas Chinesas/farmacologia , Helicobacter pylori/efeitos dos fármacos , Phellodendron/química , Urease/antagonistas & inibidores , Berberina/farmacologia , Canavalia/enzimologia , China , Medicamentos de Ervas Chinesas/química , Helicobacter pylori/enzimologia
11.
Nutrients ; 7(10): 8657-69, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26506375

RESUMO

Millettiae speciosae Champ. Leguminosae (MSC), is a well-known Chinese herb traditionally used as food material and medicine for enhancing physical strength. Our preliminary study found that the aqueous extract of this herb (MSE) had an anti-fatigue effect. In this paper, we further separated MSE into total polysaccharides (MSP) and supernatant (MSS) by alcohol precipitation, and explored which fraction was active for its anti-fatigue effect. Mice were orally administered with MSP or MSS at the doses of 200, 400, and 800 mg/kg for 20 days and the anti-fatigue effect was assessed by exhaustive swimming exercise (ESE). The biochemical parameters related to fatigue after ESE and the in vitro antioxidant activity of active fraction were determined. Our results showed that MSP, instead of MSS, significantly extended the swimming time to exhaustion (p < 0.05), indicating that MSP is responsible for the anti-fatigue effect of MSE. In addition, MSP treatment increased the levels of glucose (Glu) and muscle glycogen, whereas it decreased the accumulations of blood urea nitrogen (BUN) and lactic acid (Lac). Moreover, ESE increased the levels of creatine phosphokinase (CK), lactic dehydrogenase (LDH), and malondialdehyde (MDA) but reduced superoxide dismutase (SOD) and glutathione (GSH) in plasma. In contrast, MSP inhibited all the above changes relating to fatigue. Furthermore, an in vitro antioxidant test revealed that MSP dose-dependently scavenged ·OH and DPPH free radicals. Taken together, these findings strongly suggested that MSP was able to alleviate physical fatigue by increasing energy resources and decreasing accumulation of detrimental metabolites. The antioxidant activity may crucially contribute to the observed anti-fatigue effect of MSP.


Assuntos
Antioxidantes/uso terapêutico , Fabaceae/química , Fadiga/tratamento farmacológico , Resistência Física/efeitos dos fármacos , Fitoterapia , Polissacarídeos/uso terapêutico , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Fadiga/metabolismo , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Natação
12.
J Ethnopharmacol ; 162: 69-78, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25557028

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Baicalin and scutellarin are the principal bioactive components of Scutellaria baicalensis Georgi which has extensively been incorporated into heat-clearing and detoxification formulas for the treatment of Helicobacter pylori-related gastrointestinal disorders in traditional Chinese medicine. However, the mechanism of action remained to be defined. AIM OF THE STUDY: To explore the inhibitory effect, kinetics and mechanism of Helicobacter pylori urease (the vital pathogenetic factor for Helicobacter pylori infection) inhibition by baicalin and scutellarin, for their therapeutic potential. MATERIALS AND METHODS: The ammonia formations, indicator of urease activity, were examined using modified spectrophotometric Berthelot (phenol-hypochlorite) method. The inhibitory effect of baicalin and scutellarin was characterized with IC50 values, compared to acetohydroxamic acid (AHA), a well known Helicobacter pylori urease inhibitor. Lineweaver-Burk and Dixon plots for the Helicobacter pylori urease inhibition of baicalin and scutellarin was constructed from the kinetic data. SH-blocking reagents and competitive active site Ni(2+) binding inhibitors were employed for mechanism study. Molecular docking technique was used to provide some information on binding conformations as well as confirm the inhibition mode. Moreover, cytotoxicity experiment using Gastric Epithelial Cells (GES-1) was evaluated. RESULTS: Baicalin and scutellarin effectively suppressed Helicobacter pylori urease in dose-dependent and time-independent manner with IC50 of 0.82±0.07 mM and 0.47±0.04 mM, respectively, compared to AHA (IC50=0.14±0.05 mM). Structure-activity relationship disclosed 4'-hydroxyl gave flavones an advantage to binding with Helicobacter pylori urease. Kinetic analysis revealed that the types of inhibition were non-competitive and reversible with inhibition constant Ki of 0.14±0.01 mM and 0.18±0.02 mM for baicalin and scutellarin, respectively. The mechanism of urease inhibition was considered to be blockage of the SH groups of Helicobacter pylori urease, since thiol reagents (L,D-dithiothreitol, L-cysteine and glutathione) abolished the inhibitory action and competitive active site Ni(2+) binding inhibitors (boric acid and sodium fluoride) carried invalid effect. Molecular docking study further supported the structure-activity analysis and indicated that baicalin and scutellarin interacted with the key residues Cys321 located on the mobile flap through S-H·π interaction, but did not interact with active site Ni(2+). Moreover, Baicalin (at 0.59-1.05 mM concentrations) and scutellarin (at 0.23-0.71 mM concentrations) did not exhibit significant cytotoxicity to GES-1. CONCLUSIONS: Baicalin and scutellarin were non-competitive inhibitors targeting sulfhydryl groups especially Cys321 around the active site of Helicobacter pylori urease, representing potential to be good candidate for future research as urease inhibitor for treatment of Helicobacter pylori infection. Furthermore, our work gave additional scientific support to the use of Scutellaria baicalensis in traditional Chinese medicine (TCM) to treat gastrointestinal disorders.


Assuntos
Apigenina/farmacologia , Flavonoides/farmacologia , Glucuronatos/farmacologia , Helicobacter pylori/enzimologia , Urease/antagonistas & inibidores , Apigenina/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Glucuronatos/química , Humanos , Simulação de Acoplamento Molecular , Urease/química , Urease/metabolismo
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