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1.
Emerg Microbes Infect ; 9(1): 2417-2432, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33115324

RESUMO

Candida albicans is a common fungal pathogen in humans that colonizes the skin and mucosal surfaces of the majority healthy individuals. How C. albicans disseminates into the bloodstream and causes life-threatening systemic infections in immunocompromised patients remains unclear. Plasminogen system activation can degrade a variety of structural proteins in vivo and is involved in several homeostatic processes. Here, for the first time, we characterized that C. albicans could capture and "subvert" host plasminogen to invade host epithelial cell surface barriers through cell-wall localized Eno1 protein. We found that the "subverted" plasminogen system plays an important role in development of invasive infection caused by C. albicans in mice. Base on this finding, we discovered a mouse monoclonal antibody (mAb) 12D9 targeting C. albicans Eno1, with high affinity to the 254FYKDGKYDL262 motif in α-helices 6, ß-sheet 6 (H6S6) loop and direct blocking activity for C. albicans capture host plasminogen. mAb 12D9 could prevent C. albicans from invading human epithelial and endothelial cells, and displayed antifungal activity and synergistic effect with anidulafungin or fluconazole in proof-of-concept in vivo studies, suggesting that blocking the function of cell surface Eno1 was effective for controlling invasive infection caused by Candida spp. In summary, our study provides the evidence of C. albicans invading host by "subverting" plasminogen system, suggesting a potential novel treatment strategy for invasive fungal infections.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antifúngicos/administração & dosagem , Candida albicans/patogenicidade , Candidemia/prevenção & controle , Fosfopiruvato Hidratase/metabolismo , Plasminogênio/metabolismo , Anidulafungina/administração & dosagem , Anidulafungina/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Antifúngicos/farmacologia , Células CACO-2 , Candidemia/metabolismo , Modelos Animais de Doenças , Sinergismo Farmacológico , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/microbiologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Feminino , Fluconazol/administração & dosagem , Fluconazol/farmacologia , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Fosfopiruvato Hidratase/química , Ligação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína
2.
Chin J Nat Med ; 17(8): 616-623, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472899

RESUMO

Loureirin A is a major active component of Draconis sanguis, a traditional Chinese medicine. This work aimed to investigate the activity of loureirin A against Candida albicans biofilms. 2, 3-Bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT)reduction assay and scanning electron microscopy were used to investigate the anti-biofilm effect. Minimal inhibitory concentration testing and time-kill curve assay were used to evaluate fungicidal activity. Cell surface hydrophobicity (CSH) assay and hyphal formation experiment were respectively carried out to investigate adhesion and morphological transition, two virulence traits of C. albicans. Real-time RT-PCR was used to investigate gene expression. Galleria mellonella-C. albicans and Caenorhabditis elegans-C. albicans infection models were used to evaluate the in-vivo antifungal effect. Human umbilical vein endothelial cells and C. elegans nematodes were used to evaluate the toxicity ofloureirin A. Our data indicated that loureirin A had a significant effect on inhibiting C. albicans biofilms, decreasing CSH, and suppressing hyphal formation. Consistently, loureirin A down-regulated the expression of some adhesion-related genes and hypha/biofilm-related genes. Moreover, loureirin A prolonged the survival of Galleria mellonella and Caenorhabditis elegans in C. albicans infection models and exhibited low toxicity. Collectively, loureirin A inhibits fungal biofilms, and this effect may be associated with the suppression of pathogenic traits, adhesion and hyphal formation.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Chalconas/farmacologia , Animais , Biofilmes/crescimento & desenvolvimento , Caenorhabditis elegans , Candida albicans/genética , Candidíase/microbiologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Células Cultivadas , Modelos Animais de Doenças , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Humanos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Hifas/patogenicidade , Medicina Tradicional Chinesa , Testes de Sensibilidade Microbiana , Mariposas
3.
Artigo em Inglês | MEDLINE | ID: mdl-28303159

RESUMO

This study was designed to investigate the antifungal activity of a hydroalcoholic extract from Flos Rosae Chinensis (FRC) combined with fluconazole (FCZ) against clinical isolates of Candida albicans resistant to FCZ. The minimum inhibitory concentration (MIC) of FRC was determined using a checkerboard microdilution assay. The synergistic effects of the combination of FRC and FCZ against clinical isolates of C. albicans resistant to FCZ were further confirmed by constructing time-growth curves and performing an agar diffusion test. FRC alone exerted efficient antifungal activities against C. albicans within a MIC80 ranging from 20 µg/ml to 40 µg/ml. FRC failed to enhance the effects of FCZ against sensitive C. albicans strains, although it rendered FCZ-resistant C. albicans more sensitive. These results were further confirmed by the result of in vivo study. Our study is the first to discover that FRC can inhibit the growth of C. albicans to a certain degree. An FRC antifungal mechanism study showed that FRC strengthens FCZ to inhibit the action of ergosterol biosynthesis by promoting the transformation of lanosterol to eburicol, suggesting that the antifungal mechanism of FRC involves the inhibition of ergosterol biosynthesis.

4.
Microbiol Immunol ; 60(2): 82-92, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26891940

RESUMO

This study aimed to investigate the antifungal activity of Rubus chingii extract in combination with fluconazole (FLC) against FLC-resistant Candida albicans 100 in vitro. A R. chingii extract and FLC-resistant C. albicans fungus suspension were prepared. The minimum inhibitory concentration and fractional inhibitory concentration index of R. chingii extract combined with FLC against C. albicans were determined, after which growth curves for C. albicans treated with R. chingii extract, FLC alone and a combination of these preparations were constructed. Additionally, the mechanisms of drug combination against C. albicans were explored by flow cytometry, gas chromatographic mass spectrometry and drug efflux pump function detection. R. chingii extract combined with FLC showed significant synergy. Flow cytometry suggested that C. albicans cells mainly arrest in G1 and S phases when they have been treated with the drug combination. The drug combination resulted in a marked decrease in the ergosterol content of the cell membrane. Additionally, efflux of Rhodamine 6G decreased with increasing concentrations of R. chingii extract. R. chingii extract combined with FLC has antifungal activity against FLC-resistant C. albicans.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Fluconazol/farmacologia , Extratos Vegetais/farmacologia , Rubus/química , Apoptose/efeitos dos fármacos , Candida albicans/citologia , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Ciclo Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Farmacorresistência Fúngica , Sinergismo Farmacológico , Ergosterol/metabolismo , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Rodaminas/metabolismo
5.
Biol Pharm Bull ; 37(2): 268-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24492724

RESUMO

Over-expression of the Candida drug resistance gene CDR1 is a common mechanism generating azole-resistant Candida albicans in clinical isolates. CDR1 is transcriptionally activated through the binding of the transcription factor Tac1p to the cis-acting drug-responsive element (DRE) in its promoter. We previously demonstrated that the combination of fluconazole (FLC) and berberine (BBR) produced significant synergy when used against FLC-resistant C. albicans in vitro. In this study, we found that BBR inhibited both the up-regulation of CDR1 mRNA and the transport function of Cdr1p induced by fluphenazine (FNZ). Further, electrophoretic mobility shift assays suggested that the transcription activation complex of protein-DRE was disrupted by BBR, and electrospray ionization mass spectrometry analysis showed that BBR bound to the DRE of CDR1. Thus we propose that BBR inhibits the FNZ-induced transcriptional activation of CDR1 in C. albicans by blocking transcription factor binding to the DRE of CDR1. These results contribute to our understanding of the mechanism of synergistic effect of BBR and FLC.


Assuntos
Antifúngicos/farmacologia , Berberina/farmacologia , Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Flufenazina/efeitos adversos , Proteínas Fúngicas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Extratos Vegetais/farmacologia , Candida albicans/metabolismo , Sinergismo Farmacológico , Flufenazina/uso terapêutico , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , RNA Mensageiro/metabolismo , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima
6.
Antimicrob Agents Chemother ; 58(4): 2344-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24514088

RESUMO

Pterostilbene (PTE) is a stilbene-derived phytoalexin that originates from several natural plant sources. In this study, we evaluated the activity of PTE against Candida albicans biofilms and explored the underlying mechanisms. In 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) reduction assays, biofilm biomass measurement, confocal laser scanning microscopy, and scanning electron microscopy, we found that ≤16 µg/ml PTE had a significant effect against C. albicans biofilms in vitro, while it had no fungicidal effect on planktonic C. albicans cells, which suggested a unique antibiofilm effect of PTE. Then we found that PTE could inhibit biofilm formation and destroy the maintenance of mature biofilms. At 4 µg/ml, PTE decreased cellular surface hydrophobicity (CSH) and suppressed hyphal formation. Gene expression microarrays and real-time reverse transcription-PCR showed that exposure of C. albicans to 16 µg/ml PTE altered the expression of genes that function in morphological transition, ergosterol biosynthesis, oxidoreductase activity, and cell surface and protein unfolding processes (heat shock proteins). Filamentation-related genes, especially those regulated by the Ras/cyclic AMP (cAMP) pathway, including ECE1, ALS3, HWP1, HGC1, and RAS1 itself, were downregulated upon PTE treatment, indicating that the antibiofilm effect of PTE was related to the Ras/cAMP pathway. Then, we found that the addition of exogenous cAMP reverted the PTE-induced filamentous growth defect. Finally, with a rat central venous catheter infection model, we confirmed the in vivo activity of PTE against C. albicans biofilms. Collectively, PTE had strong activities against C. albicans biofilms both in vitro and in vivo, and these activities were associated with the Ras/cAMP pathway.


Assuntos
Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Animais , Candida albicans/metabolismo , Feminino , Proteínas Fúngicas/metabolismo , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley
7.
PLoS One ; 8(11): e79671, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260276

RESUMO

Candida albicans is the most common human fungal pathogen and has a high propensity to develop biofilms that are resistant to traditional antifungal agents. In this study, we investigated the effect of tetrandrine (TET) on growth, biofilm formation and yeast-to-hypha transition of C. albicans. We characterized the inhibitory effect of TET on hyphal growth and addressed its possible mechanism of action. Treatment of TET at a low concentration without affecting fungal growth inhibited hyphal growth in both liquid and solid Spider media. Real-time RT-PCR revealed that TET down-regulated the expression of hypha-specific genes ECE1, ALS3 and HWP1, and abrogated the induction of EFG1 and RAS1, regulators of hyphal growth. Addition of cAMP restored the normal phenotype of the SC5314 strain. These results indicate that TET may inhibit hyphal growth through the Ras1p-cAMP-PKA pathway. In vivo, at a range of concentrations from 4 mg/L to 32 mg/L, TET prolonged the survival of C. albicans-infected Caenorhabditis elegans significantly. This study provides useful information for the development of new strategies to reduce the incidence of C. albicans biofilm-associated infections.


Assuntos
Antifúngicos/farmacologia , Benzilisoquinolinas/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Candida albicans/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
8.
Eur J Clin Pharmacol ; 66(11): 1099-108, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20812009

RESUMO

PURPOSE: Rivaroxaban is a newly developed oral medicine that direct inhibits factor Xa for the prevention and treatment of thromboembolic disorders. The objective of this study was to compare the efficacy and safety of rivaroxaban versus enoxaparin, a medicine routinely used for thromboprophylaxis after total hip or knee arthroplasty. METHODS: We performed a meta-analysis of relevant randomized controlled trials (RCTs) identified in PubMed, Cochrane library, and Embase. The primary efficacy outcome for our meta-analysis was total venous thromboembolism (VTE) and all-cause mortality. The primary safety outcome was bleeding events, which were categorized as major, clinically relevant non-major, or minor events. RESULTS: Eight RCTs, involving 15,586 patients, were included in our meta-analysis. Compared to enoxaparin, thromboprophylaxis with rivaroxaban was associated with significantly fewer VTE and all-cause mortality [9,244 patients, risk ratio (RR) 0.56, 95% confidence interval (CI) 0.39-0.80] cases and a similar incidence of bleeding cases (major bleeding events: 13,384 patients, RR 1.65, 95% CI 0.93-2.93; clinically relevant non-major bleeding events: 13,384 patients, RR 1.21, 95% CI 0.98-1.50; total bleeding events, 13,384 patients, RR 1.10, 95% CI 0.97-1.24). The total hip or knee arthroplasty subgroup analysis revealed consistent efficacy and safety findings. CONCLUSIONS: Rivaroxaban was more effective than the recommended dose of enoxaparin and had a similar safety profile for thromboprophylaxis after hip and knee arthroplasty.


Assuntos
Anticoagulantes/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Enoxaparina/uso terapêutico , Morfolinas/uso terapêutico , Tiofenos/uso terapêutico , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/efeitos adversos , Artroplastia de Quadril/mortalidade , Artroplastia do Joelho/mortalidade , Método Duplo-Cego , Enoxaparina/efeitos adversos , Hemorragia/induzido quimicamente , Humanos , Incidência , Morfolinas/efeitos adversos , Estudos Multicêntricos como Assunto , Razão de Chances , Prevenção Primária/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Rivaroxabana , Tiofenos/efeitos adversos , Resultado do Tratamento , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/mortalidade
9.
Int J Antimicrob Agents ; 36(1): 58-65, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20400271

RESUMO

The aim of this study was to compare more conclusively the efficacy and safety of moxifloxacin, a new respiratory fluoroquinolone antibiotic, with beta-lactam-based standard therapy, which has been reported to possess good efficacy for community-acquired pneumonia (CAP). A meta-analysis of randomised controlled trials (RCTs) identified in PubMed, the Cochrane Library and Embase was performed. Seven RCTs, involving 3903 patients, were included in the meta-analysis. Moxifloxacin monotherapy was associated with similar clinical treatment success rates [clinically evaluable population, odds ratio (OR)=1.15, 95% confidence interval (CI) 0.81-1.64; intention-to-treat population, OR=1.11, 95% CI 0.86-1.42] and similar mortality (OR=0.98, 95% CI 0.66-1.46) compared with beta-lactam-based standard therapy for CAP. Microbiological treatment success rates in the moxifloxacin group were significantly higher than in the beta-lactam-based therapy group with a statistical margin (OR=1.69, 95% CI 1.02-2.80). No difference was found regarding the incidence of adverse events and serious adverse events between moxifloxacin and beta-lactam-based standard therapy. This meta-analysis provides evidence that moxifloxacin not only can be used as effectively and safely as beta-lactam-based standard therapy for CAP but also possesses a favourable pathogen eradication rate. The once-daily dosing of moxifloxacin monotherapy may be a useful alternative for beta-lactam-based standard therapy.


Assuntos
Antibacterianos/uso terapêutico , Compostos Aza/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Pneumonia Bacteriana/tratamento farmacológico , Quinolinas/uso terapêutico , beta-Lactamas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fluoroquinolonas , Humanos , Pessoa de Meia-Idade , Moxifloxacina , Resultado do Tratamento , Adulto Jovem
10.
J Microbiol Biotechnol ; 19(8): 803-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19734718

RESUMO

Recent evidence has revealed the occurrence of an apoptotic phenotype in Candida albicans that is inducible with environmental stresses such as acetic acid, hydrogen peroxide, and amphotericin B. In the present study, we found that the Chinese herbal medicine Baicalein (BE), which was one of the skullcapflavones, can induce apoptosis in C. albicans. The apoptotic effects of BE were detected by flow cytometry using Annexin V-FITC and DAPI, and it was confirmed by transmission electron microscopy analysis. After exposure to 4 microg/ml BE for 12 h, about 10% of C. albicans cells were apoptotic. Both the increasing intracellular levels of reactive oxygen species (ROS) and upregulation of some redox-related genes (CAP1, SOD2, TRR1) were observed. Furthermore, we compared the survivals of CAP1 deleted, wild-type, and overexpressed strains and found that Cap1p attenuated BE-initiated cell death, which was coherent with a higher mRNA level of the CAP1 gene. In addition, the mitochondrial membrane potential of C. albicans cells changed significantly ( p<0.001) upon BE treatment compared with control. Taken together, our results indicate that BE treatment induces apoptosis in C.albicans cells, and the apoptosis was associated with the breakdown of mitochondrial membrane potential.


Assuntos
Antioxidantes/administração & dosagem , Apoptose/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Flavanonas/administração & dosagem , Fatores de Transcrição de Zíper de Leucina Básica , Candida albicans/fisiologia , Candida albicans/ultraestrutura , Candidíase/tratamento farmacológico , Candidíase/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , RNA Fúngico/biossíntese , RNA Fúngico/genética , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
11.
Clin Exp Pharmacol Physiol ; 36(10): e40-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19413603

RESUMO

1. The aim of the present study was to investigate the effects of ascorbic acid (AA) on the antifungal activity of fluconazole (FCZ) in a systemic murine candidiasis model as well as in vitro. 2. The murine model was established by infusion of Candida albicans via the tail vein. Control mice received no further treatment. Other groups of mice were injected with FCZ (0.5 mg/kg, i.p.) and then treated or not with 50 or 500 mg/kg AA intragastrically (i.g.) or i.p. In all groups, FCZ was administered i.p. 2 h after fungal inoculation, whereas AA was administered 6 h after fungal inoculation. Survival rate, kidney fungal burden and renal pathological changes were evaluated. 3. The in vitro effects of AA (5, 1 and 0.2 mmol/L) on the growth of various Candida strains in the presence of FCZ (0.125-64 microg/mL) were also investigated. The in vitro effects of two anti-oxidants, namely N-acetylcysteine (NAC; 5, 1 and 0.2 mmol/L) and reduced glutathione (GSH; 5, 1 and 0.2 mmol/L), on FCZ activity were evaluated to determine the mechanism of action of AA. 4. Intragastric administration of AA (50 or 500 mg/kg) significantly decreased the antifungal effect of 0.5 mg/kg FCZ. Although i.p. administration of AA (50 or 500 mg/kg) had no significant effect on the survival of mice, it dose-dependently inhibited the activity of FCZ, with significant inhibition observed with 500 mg/kg AA. 5. In vitro, AA decreased the activity of FCZ against various Candida strains. Both NAC and GSH dose-dependently decreased the activity of FCZ. 6. The results of the present study indicate that AA inhibits the antifungal activity of FCZ, suggesting that the two should not be used together clinically for the treatment of candidiasis.


Assuntos
Antifúngicos/uso terapêutico , Ácido Ascórbico/farmacologia , Candidíase/tratamento farmacológico , Fluconazol/uso terapêutico , Animais , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase/mortalidade , Modelos Animais de Doenças , Antagonismo de Drogas , Avaliação Pré-Clínica de Medicamentos , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Camundongos , Testes de Sensibilidade Microbiana
12.
J Ethnopharmacol ; 115(1): 1-8, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-17964746

RESUMO

The study was aimed to investigate the effects and mechanism of action of Changtai granule (CT), a traditional compound Chinese medicinal formula, in rodent 2,4,6-trinitrobenzene sulfonic acid (TNBS) colitis. Rats with TNBS/ethanol-induced colitis were used. The colonic wet weight, myeloperoxidase (MPO) activity, macroscopic and histological colon injury was observed. Inflammation cytokines were determined by ELISA methods and semi-quantitative RT-PCR. When dosed orally once daily, CT markedly attenuated TNBS-induced colitis. CT significantly attenuated colonic wet weight, macroscopic and histological colon injury. CT decreased mucosal mRNA levels for several inflammatory mediators: inducible nitric oxide synthase, cyclooxygenase 2, and macrophage inflammatory protein 2. CT also decreased mucosal mRNA and protein levels of T effectors cytokines: tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2) and interferon-gamma (IFN-gamma). Systemic levels of these cytokines were also dramatically attenuated. CD3/CD28-mediated costimulation of T helper 1 effector cytokines release in lamina propria mononuclear cells (LPMC) was markedly inhibited by CT ex vivo and in vitro. Also CT prevented cytokines production by nuclear factor-kappaB (NF-kappaB). The potential anti-inflammatory and immunomodulatory effect of CT in TNBS colitis suggests that CT may be an effective treatment approach for inflammatory bowel disease.


Assuntos
Colite/tratamento farmacológico , Inflamação/tratamento farmacológico , Preparações de Plantas/farmacologia , Animais , Colite/induzido quimicamente , Colite/imunologia , Ensaio de Imunoadsorção Enzimática , Euphorbia/química , Haptenos , Inflamação/etiologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Masculino , Medicina Tradicional Chinesa , Phellodendron/química , Polygonum/química , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sanguisorba/química , Ácido Trinitrobenzenossulfônico
13.
Eur J Pharmacol ; 543(1-3): 77-82, 2006 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-16808912

RESUMO

Besides blood pressure, blood pressure variability and baroreflex sensitivity maybe important factors determining organ damage in hypertension. This study was designed to investigate the effects of various antihypertensive drugs on blood pressure and blood pressure variability reductions, baroreflex sensitivity, and target organ damage in spontaneously hypertensive rats (SHR). The dose is 20 mg/kg/day for atenolol, and 10 mg/kg/day for nifedipine, irbesartan and hydrochlorothiazide. We used relatively low doses of drugs to avoid a very remarkable normalization of blood pressure in the treatment, which would make it much difficult to distinguish the contribution of blood pressure variability and baroreflex sensitivity to organ protection from that of blood pressure. Drugs at the aforementioned doses were mixed into rat chow. SHR were treated for 4 months. Blood pressure was then continuously recorded for 24 h. After the determination of baroreflex sensitivity, rats were killed for organ-damage evaluation. It was found that long-term treatment with atenolol, nifedipine, irbesartan or hydrochlorothiazide all markedly reduced blood pressure variability, enhanced baroreflex sensitivity, and produced significant organ protection. Compared with blood pressure level, blood pressure variability and baroreflex sensitivity values showed a much closer or similar relationship with organ-damage parameters in every treatment group of rats. Multiple-regression analysis showed that the decrease in left ventricular hypertrophy, the decrease in aortic hypertrophy and the amelioration in renal lesion were all most closely correlated with the increase in baroreflex sensitivity and the decrease in systolic blood pressure variability. In conclusion, long-term treatment with atenolol, nifedipine, irbesartan or hydrochlorothiazide produced organ protection in SHR. Besides the blood pressure reduction, the decrease in blood pressure variability and the restoration of baroreflex sensitivity may contribute to this organ protection.


Assuntos
Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Atenolol/farmacologia , Atenolol/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Ritmo Circadiano , Hidroclorotiazida/farmacologia , Hidroclorotiazida/uso terapêutico , Hipertensão/patologia , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Irbesartana , Nefropatias/patologia , Nefropatias/prevenção & controle , Masculino , Nifedipino/farmacologia , Nifedipino/uso terapêutico , Ratos , Ratos Endogâmicos SHR , Tetrazóis/farmacologia , Tetrazóis/uso terapêutico
14.
J Ethnopharmacol ; 103(1): 76-84, 2006 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16169173

RESUMO

Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We used bioassay-guided fractionation to have isolated eight steroid saponins from Tribulus terrestris L., which were identified as hecogenin-3-O-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (TTS-8), tigogenin-3-O-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (TTS-9), hecogenin-3-O-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (TTS-10), hecogenin-3-O-beta-D-xylopyranosyl (1-->3)-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (TTS-11), tigogenin-3-O-beta-D-xylopyranosyl (1-->2)-[beta-D-xylopyranosyl (1-->3)]-beta-D-glucopyranosyl (1-->4)-[alpha-L-rhamnopyranosyl (1-->2)]-beta-D-galactopyranoside (TTS-12), 3-O-[beta-D-xylopyranosyl (1-->2)-[beta-D-xylopyranosyl (1-->3)]-beta-D-glucopyranosyl (1-->4)-[alpha-L-rhamnopyranosyl (1-->2)]-beta-D-galactopyranosyl]-26-O-beta-D-glucopyranosyl-22-methoxy-(3beta,5alpha,25R)-furostan-3,26-diol (TTS-13), hecogenin-3-O-beta-D-glucopyranosyl (1-->2)-[beta-D-xylopyranosyl (1-->3)]-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (TTS-14), tigogenin-3-O-beta-D-glucopyranosyl (1-->2)-[beta-D-xylopyranosyl (1-->3)]-beta-D-glucopyranosyl (1-->4)-beta-D-galactopyranoside (TTS-15). The in vitro antifungal activities of the eight saponins against five yeasts, Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis and Cryptococcus neoformans were studied using microbroth dilution assay. In vivo activity of TTS-12 in a Candida albicans vaginal infection model was studied in particular. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and Cryptococcus neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against Candida albicans (MIC(80) = 10 and 2.3 microg/mL) and Cryptococcus neoformans (MIC(80) = 1.7 and 6.7 microg/mL). Phase contrast microscopy showed that TTS-12 inhibited hyphal formation, an important virulence factor of Candida albicans, and transmission electron microscopy showed that TTS-12 destroyed the cell membrane of Candida albicans. In conclusion, TTS-12 has significant in vitro and in vivo antifungal activity, weakening the virulence of Candida albicans and killing fungi through destroying the cell membrane.


Assuntos
Antifúngicos/farmacologia , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Tribulus , Animais , Candida albicans/efeitos dos fármacos , Candida albicans/ultraestrutura , Candidíase Vulvovaginal/tratamento farmacológico , Feminino , Testes de Sensibilidade Microbiana , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Tribulus/química
15.
Biol Pharm Bull ; 28(12): 2211-5, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16327151

RESUMO

Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L., namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-beta-D-xylopyranosyl(1-->2)-[beta-D-xylopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-[alpha-L-rhamnopyranosyl(1-->2)]-beta-D-galactopyranoside and tigogenin-3-O-beta-D-glucopyranosyl(1-->2)-[beta-D-xylopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis, Candida krusei, and Cryptococcus neoformans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC(80)=4.4, 9.4 microg/ml), C. neoformans (MIC(80)=10.7, 18.7 microg/ml) and inherently resistant C. krusei (MIC(80)=8.8, 18.4 microg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans.


Assuntos
Antifúngicos/farmacologia , Farmacorresistência Fúngica , Saponinas/farmacologia , Esteroides/farmacologia , Tribulus , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Feminino , Fluconazol/farmacologia , Galactose/farmacologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Saponinas/química , Saponinas/isolamento & purificação , Esteroides/química , Esteroides/isolamento & purificação , Fatores de Tempo , Tribulus/química , Doenças Vaginais/tratamento farmacológico , Doenças Vaginais/microbiologia
16.
World J Gastroenterol ; 11(23): 3539-43, 2005 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-15962370

RESUMO

AIM: To study the effects of Changtai granules (CTG), a traditional compound Chinese medicine, on chronic trinitrobenzene sulfonic acid-induced colitis in rats. METHODS: Healthy adult Sprague-Dawley (SD) rats of both sexes, weighing 250-300 g, were employed in the present study. The rat colitis models were induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) enemas at a concentration of 100 mg/kg in 50% ethanol. The experimental animals were randomly divided into dexamethasone (DX) treatment, CTG treatment, and model control groups, which were intracolicly treated daily with DX (0.2 mg/kg), CTG at doses of 2.9, 5.7 and 11.4 g crude drug/kg, and the equal amount of saline respectively from 6 h following induction of the colitis in rats inflicted with TNBS to the end of study. A normal control group of rats treated without TNBS but saline enema was also included in the study. After 3 wk of treatment, the animals were assessed for colonal inflammatory and ulcerative responses with respect to mortality, frequency of diarrhea, histology and myeloperoxidase activity (MPO). RESULTS: The therapeutic effect of CTG on ulcerative colitis (UC) was better than DX. CTG effectively inhibited the activity of granulocytes, macrophages and monocytes in a dose-dependent manner. Also it reduced MPO and formation of inflammation in colonic mucosal tissue. Furthermore, administration of CTG significantly prevented body mass loss and death, and decreased frequency of diarrhea in UC rats, when compared with the model control group rats. CONCLUSION: CTG would prove to be an ideal drug for chronic UC, and is warranted to be studied further.


Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Medicina Tradicional Chinesa , Ácido Trinitrobenzenossulfônico/toxicidade , Animais , Colite/parasitologia , Diarreia/etiologia , Inflamação , Ratos , Ratos Sprague-Dawley
17.
Antimicrob Agents Chemother ; 49(2): 584-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15673737

RESUMO

Candida albicans biofilms are structured microbial communities with high levels of drug resistance. Farnesol, a quorum-sensing molecule that inhibits hyphal formation in C. albicans, has been found to prevent biofilm formation by C. albicans. There is limited information, however, about the molecular mechanism of farnesol against biofilm formation. We used cDNA microarray analysis to identify the changes in the gene expression profile of a C. albicans biofilm inhibited by farnesol. Confocal scanning laser microscopy was used to visualize and confirm normal and farnesol-inhibited biofilms. A total of 274 genes were identified as responsive, with 104 genes up-regulated and 170 genes down-regulated. Independent reverse transcription-PCR analysis was used to confirm the important changes detected by microarray analysis. In addition to hyphal formation-associated genes (e.g., TUP1, CRK1, and PDE2), a number of other genes with roles related to drug resistance (e.g., FCR1 and PDR16), cell wall maintenance (e.g., CHT2 and CHT3), and iron transport (e.g., FTR2) were responsive, as were several genes encoding heat shock proteins (e.g., HSP70, HSP90, HSP104, CaMSI3, and SSA2). Further study of these differentially regulated genes is warranted to evaluate how they may be involved in C. albicans biofilm formation. Consistent with the down-regulation of the cell surface hydrophobicity-associated gene (CSH1), the water-hydrocarbon two-phase assay showed a decrease in cell surface hydrophobicity in the farnesol-treated group compared to that in the control group. Our data provide new insight into the molecular mechanism of farnesol against C. albicans biofilm formation.


Assuntos
Biofilmes , Candida albicans/metabolismo , DNA Complementar/genética , DNA Fúngico/genética , Farneseno Álcool/farmacologia , Regulação Fúngica da Expressão Gênica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Candida albicans/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/ultraestrutura , Meios de Cultura , Sondas de DNA , DNA Complementar/biossíntese , DNA Fúngico/biossíntese , Farmacorresistência Fúngica , Proteínas de Choque Térmico/metabolismo , Hibridização In Situ , Microscopia Confocal , Proteínas de Transferência de Fosfolipídeos/genética , RNA Fúngico/biossíntese , RNA Fúngico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Acta Pharmacol Sin ; 25(6): 817-21, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15169638

RESUMO

AIM: To investigate the influence of esculentoside A (EsA) on immunological function and its mechanism of anti-inflammation. METHODS: Interleukin-1 production was measured by thymocyte co-stimulating assay; the radioactivity of [(3)H]arachidonic acid (AA) was used to evaluate the release of AA; prostaglandin E2 production was measured with radioimmunoassay (RIA); IL-2 and IFN-gamma were detected by ELISA method. RESULTS: EsA (3-12 micromol/L)could potently inhibit the production of IL-1 and PGE(2) from both silent and LPS induced macrophages. EsA had no significant effect on the release of AA from murine macrophages. EsA could inhibit the production of IL-2 from murine lymphocytes induced by ConA, but not affect the production from silent lymphocytes. EsA showed no effect on the production of IFN-gamma from both silent and ConA induced lymphocytes. CONCLUSION: EsA could affect the immunological function through inhibiting the production of IL-2 from activated splenocytes and the inhibition of production of IL-1 and PGE(2) might be one of the anti-inflammation mechanisms of EsA.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Dinoprostona/biossíntese , Interleucina-1/biossíntese , Interleucina-2/biossíntese , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , Saponinas/farmacologia , Animais , Ácido Araquidônico/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Interferon gama/biossíntese , Linfócitos/metabolismo , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Ácido Oleanólico/isolamento & purificação , Phytolacca/química , Plantas Medicinais/química , Saponinas/isolamento & purificação
19.
Acta Pharmacol Sin ; 25(2): 148-51, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14769201

RESUMO

AIM: Computerized analysis of blood pressure in conscious freely moving rats is a sound technique for physiological and pharmacological studies. The present work, based on this technique, was designed to introduce two useful methods for the evaluation of antihypertensive drugs in conscious spontaneously hypertensive rat (SHR). They were the directly intragastric administration of drugs and modified probability sum test for evaluating the synergism of the combination of two drugs. METHODS AND RESULTS: (1) Directly intragastric administration was used in conscious rats. A catheter was inserted into stomach immediately after arterial catheter insertion. Three days after operation, blood pressure was recorded and drug might be given intragastrically via the gastric catheter. (2) Modified probability sum test was used to evaluate the synergism of two drugs. The formula was: q=P(A+B)/(PA+PB-PAxB). With this method, it was obtained: q=1.32 for the effects of the combination of atenolol and nitrendipine (20 mg/kg+10 mg/kg) on systolic blood pressure; q=1.41 for the effects of the combination of atenolol and amlodipine (10 mg/kg+1 mg/kg) on systolic blood pressure. CONCLUSION: The two methods introduced by the present work will be important and useful for antihypertensive drug evaluation in conscious freely moving rats.


Assuntos
Atenolol/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/fisiopatologia , Nitrendipino/farmacologia , Anlodipino/farmacologia , Animais , Anti-Hipertensivos , Atenolol/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Sinergismo Farmacológico , Feminino , Masculino , Nitrendipino/administração & dosagem , Ratos , Ratos Endogâmicos SHR
20.
Acta Pharmacol Sin ; 23(7): 638-44, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12100759

RESUMO

AIM: To investigate the influence of esculentoside A (EsA) on autoimmunity in mice and its possible mechanisms. METHODS: The level of anti-ds DNA antibody, proliferation of lymphoid cells, and inflammation by pathologic section of joint in mice were examined. The autoimmunity model is made through immunizing mice with formaldehyde treated Campylobacter jejuni strain CJ-S131 and Freund's complete adjuvant. The apoptosis of T cell was analyzed through morphology and flow cytometry (FACS). The expression of ICAM-1 mRNA in human umbilical vein endothelial cell line (ECV304) was determined by coupled reverse transcription and PCR amplification (RT-PCR). RESULTS: EsA could potently lower the level of anti-ds DNA antibody, inhibit the proliferation of lymphoid cells, and ameliorate inflammation in the joint of model mouse. The apoptosis of thymocyte activated by ConA was markedly accelerated while the expression of ICAM-1 mRNA in ECV304 was decreased by EsA. CONCLUSION: EsA has the positive curative effect on autoimmunity in a mouse model, which may function through inhibition of expression of ICAM-1 mRNA in ECV304 and acceleration of thymocyte apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Autoimunidade/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/biossíntese , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , Saponinas/farmacologia , Animais , Anticorpos Antinucleares/metabolismo , Linhagem Celular , Endotélio Vascular/citologia , Humanos , Inflamação/imunologia , Molécula 1 de Adesão Intercelular/genética , Camundongos , Camundongos Endogâmicos BALB C , Ácido Oleanólico/isolamento & purificação , Phytolacca/química , Plantas Medicinais/química , RNA Mensageiro/genética , Saponinas/isolamento & purificação , Timo/citologia , Cordão Umbilical/citologia
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