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1.
J Ethnopharmacol ; 280: 114409, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34265378

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The edible plant Opuntia dillenii (Ker Gawl.) Haw. commonly known as Nagphana, belongs to the Cactaceae family. It is traditionally used to treat various ailments including inflammation, gastric ulcers, diabetes, hepatitis, asthma, whooping cough and intestinal spasm. AIM OF THE STUDY: Despite its traditional use in various countries, detailed toxicological studies of O. dillenii cladode are few. Thus in the current study, toxicity of O. dillenii cladode derived methanol extract, fractions and its α-pyrones: opuntiol and opuntioside have been addressed. METHODS: The test agents were assessed using both in vitro and in vivo toxicity assays. MTT on human embryonic kidney cell line (HEK-293), tryphan blue exclusion in rat neutrophils, Cytokinesis-B block micronucleus (CBMN) in human lymphocytes and genomic DNA fragmentation using agarose gel electrophoresis were performed. In acute toxicity test, mice orally received extract (5 g/kg) for 7 days followed by measurements of relative organ weight, biochemical (blood profile, liver and kidney function test) and histological studies (liver and kidney) were carried out. Rat bone marrow micronucleus genotoxicity assay was also conducted. RESULTS: O. dillenii derived test agents were non-cytotoxic and had no effect on the integrity of DNA. Methanol extract (5 g/kg) orally administered in mice did not cause any significant change in relative organ weights, biochemical parameters and liver and kidney histology as compared to vehicle control. In parallel, extract did not stimulate micronuclei formation in rat bone marrow polychromatic erythrocytes. CONCLUSION: These results led to conclude that edible O. dillenii extract is non-toxic via the oral route and appears to be non-cyto-, hepato-, nephro- or genotoxic, thereby supporting its safe traditional use against various ailments. Therefore, opuntiol and opuntioside may serve as lead compounds in designing new drug(s) derived from edible plants.


Assuntos
Ácidos Cumáricos/toxicidade , Monossacarídeos/toxicidade , Opuntia/química , Extratos Vegetais/toxicidade , Animais , Ácidos Cumáricos/isolamento & purificação , Fragmentação do DNA/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Masculino , Metanol/química , Camundongos , Testes para Micronúcleos , Monossacarídeos/isolamento & purificação , Neutrófilos/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Pironas/isolamento & purificação , Pironas/toxicidade , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda
2.
Antivir Chem Chemother ; 28: 2040206620983780, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33353394

RESUMO

BACKGROUND: Gallium has demonstrated strong anti-inflammatory activity in numerous animal studies, and has also demonstrated direct antiviral activity against the influenza A H1N1 virus and the human immunodeficiency virus (HIV). Gallium maltolate (GaM), a small metal-organic coordination complex, has been tested in several Phase 1 clinical trials, in which no dose-limiting or other serious toxicity was reported, even at high daily oral doses for several months at a time. For these reasons, GaM may be considered a potential candidate to treat coronavirus disease 2019 (COVID-19), which is caused by the SARS-CoV-2 virus and can result in severe, sometimes lethal, inflammatory reactions. In this study, we assessed the ability of GaM to inhibit the replication of SARS-CoV-2 in a culture of Vero E6 cells. METHODS: The efficacy of GaM in inhibiting the replication of SARS-CoV-2 was determined in a screening assay using cultured Vero E6 cells. The cytotoxicity of GaM in uninfected cells was determined using the Cell Counting Kit-8 (CCK-8) colorimetric assay. RESULTS: The results showed that GaM inhibits viral replication in a dose-dependent manner, with the concentration that inhibits replication by 50% (EC50) being about 14 µM. No cytotoxicity was observed at concentrations up to at least 200 µM. CONCLUSION: The in vitro activity of GaM against SARS-CoV-2, together with GaM's known anti-inflammatory activity, provide justification for testing GaM in COVID-19 patients.


Assuntos
Anti-Inflamatórios/farmacologia , Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Compostos Organometálicos/farmacologia , Pironas/farmacologia , SARS-CoV-2/efeitos dos fármacos , Animais , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/toxicidade , Antivirais/uso terapêutico , Antivirais/toxicidade , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ferro/metabolismo , Compostos Organometálicos/uso terapêutico , Compostos Organometálicos/toxicidade , Pironas/uso terapêutico , Pironas/toxicidade , SARS-CoV-2/fisiologia , Células Vero , Replicação Viral/efeitos dos fármacos
3.
Environ Sci Pollut Res Int ; 26(12): 12071-12079, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30827024

RESUMO

Highly bioavailable plant phospholipid complex that can reverse aluminum maltolate (AlM)-induced toxicity is not yet reported. Hence, the present study was planned to investigate the impact of oxidative stress and apoptotic changes provoked by Al and ameliorative role of Bacopa phospholipid complex (BPC) in albino rats. The levels of antioxidant enzymes such as superoxide dismutase (SOD), catalase activity (CAT), glutathione peroxidase (GPx), and thiobarbituric acid-reactive substance (TBA-RS) were measured and immunohistochemistry analysis of apoptotic markers, Bax and Bcl-2, was done from the four brain regions such as the hippocampus, cerebral cortex, cerebellum, and medulla oblongata. The levels of antioxidant enzymes and apoptotic markers that were decreased on AlM induction showed a significant increase in their levels, almost as observed in the control, when treated with BPC and Bm. Our results indicate that both BPC and Bm showed a therapeutic effect against AlM toxicity; however, it was found that the therapeutic potential of BPC was more pronounced than Bm against AlM-induced neurotoxicity.


Assuntos
Antioxidantes/farmacologia , Encéfalo/fisiologia , Compostos Organometálicos/toxicidade , Extratos Vegetais/farmacologia , Pironas/toxicidade , Animais , Bacopa/química , Encéfalo/efeitos dos fármacos , Catalase/metabolismo , Cerebelo/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Hipocampo/efeitos dos fármacos , Masculino , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Fosfolipídeos , Ratos , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico
4.
Biol Trace Elem Res ; 187(1): 243-257, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29797207

RESUMO

In our previous study, chromium malate is beneficial for type 2 diabetic rats in control glycometabolism and lipid metabolism. The present study was designed to observe the chronic toxicity, lipid metabolism, learning and memory ability, and related enzymes of chromium malate in rats during the year. The results showed that pathological, toxic, feces, and urine of chromium malate (at daily doses of 10.0, 15.0, and 20.0 µg Cr/kg bm) did not change measurably. Chromium malate (at daily doses of 15.0 and 20.0 µg Cr/kg bm) could significantly reduce the levels of total cholesterol (TC), LDL, and triglyceride (TG), and increase the level of HDL in male rats compared to control group and chromium picolinate group. Significant escalating trends of the escape latency and swimming speed (Morris water maze test), and the original platform quadrant stops, residence time, and swimming speed (Space exploration test) in male rats of chromium malate groups were obtained. The SOD, GSH-Px, and TChE activities of chromium malate (at daily doses of 15.0 and 20.0 µg Cr/kg bm) were enhanced significantly in male rats compared with those of the normal control group and chromium picolinate group. Glycometabolism and related enzymes had no significant changes compared to normal control group and chromium picolinate group. These results indicated that long-term chromium malate supplementation did not cause measurable toxicity at daily doses of 10.0, 15.0, and 20.0 µg Cr/kg bm and could improve dyslipidemia and learning and memory deficits.


Assuntos
Acetilcolinesterase/metabolismo , Glutationa Peroxidase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/toxicidade , Pironas/administração & dosagem , Pironas/toxicidade , Animais , Suplementos Nutricionais , Feminino , Masculino , Ratos , Ratos Sprague-Dawley
5.
Neurotox Res ; 35(3): 584-593, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30317430

RESUMO

Glycyrrhizic acid (GA) is the most effective ingredient in the root of licorice, with important pharmacological effects. We investigate the effects of GA on mitochondrial function and biogenesis in the aluminum toxicity in PC12 cell line. After pretreatment of PC12 cells with different concentrations of GA (5-100 µM), and specific concentration of aluminum maltolate (Almal,1000 µM) for 48 h, cell viability, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), mitochondria mass, cytochrome c oxidase enzyme activity, and the ATP level of the cells were measured. The expression mRNA level of PGC-1α, NRF1, NRF2, and TFAM was confirmed by the real-time PCR quantitative method. The results showed that low concentrations of GA protected Almal-induced cell death in 48 h. It was also observed that GA reduced the ROS production and increased the ATP level. The activity of cytochrome c oxidase enzyme and also decrease of MMP were improved. In addition, GA significantly increased the expression of mitochondrial genes and mass against aluminum toxicity. GA can exert its protective effect against the toxicity of Almal through maintaining mitochondrial function and subsequently increasing energy metabolism and mitochondrial biogenesis. GA as a natural product can be considered as a supplement in neurodegenerative disease.


Assuntos
Ácido Glicirrízico/farmacologia , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Compostos Organometálicos/toxicidade , Pironas/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Células PC12 , RNA Mensageiro/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo
6.
Neurotox Res ; 35(2): 318-330, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30242626

RESUMO

The neuroprotective role of tannoid principles of Emblica officinalis (EoT), an Indian and Chinese traditional medicinal plant against memory loss in aluminum chloride-induced in vivo model of Alzheimer's disease through attenuating AChE activity, oxidative stress, amyloid and tau toxicity, and apoptosis, was recently reported in our lab. However, to further elucidate the mechanism of neuroprotective effect of EoT, the current study was designed to evaluate endoplasmic reticulum stress-suppressing and anti-inflammatory role of EoT in PC 12 and SH-SY 5Y cells. These cells were divided into four groups: control (aluminum maltolate (Al(mal)3), EoT + Al(mal)3, and EoT alone based on 3-(4, 5-dimethyl 2-yl)-2, and 5-diphenyltetrazolium bromide (MTT) assay. EoT significantly reduced Al(mal)3-induced cell death and attenuated ROS, mitochondrial membrane dysfunction, and apoptosis (protein expressions of Bax; Bcl-2; cleaved caspases 3, 6, 9, 12; and cytochrome c) by regulating endoplasmic reticulum stress (PKR-like ER kinase (PERK), α subunit of eukaryotic initiation factor 2 (EIF2-α), C/EBP-homologous protein (CHOP), and high-mobility group box 1 protein (HMGB1)). Moreover, inflammatory response (NF-κB, IL-1ß, IL-6, and TNF-α) and Aß toxicity (Aß1-42) triggered by Al(mal)3 was significantly normalized by EoT. Our results suggested that EoT could be a possible/promising and novel therapeutic lead against Al-induced neurotoxicity. However, further extensive research is needed to prove its efficacy in clinical studies.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Phyllanthus emblica , Extratos Vegetais/farmacologia , Pironas/toxicidade , Alumínio/toxicidade , Animais , Apoptose/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Neurônios/metabolismo , Células PC12 , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Ratos
7.
Int J Nanomedicine ; 13: 6465-6479, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410332

RESUMO

INTRODUCTION: Kojic monooleate (KMO) is an ester derived from a fungal metabolite of kojic acid with monounsaturated fatty acid, oleic acid, which contains tyrosinase inhibitor to treat skin disorders such as hyperpigmentation. In this study, KMO was formulated in an oil-in-water nanoemulsion as a carrier for better penetration into the skin. METHODS: The nanoemulsion was prepared by using high and low energy emulsification technique. D-optimal mixture experimental design was generated as a tool for optimizing the composition of nanoemulsions suitable for topical delivery systems. Effects of formulation variables including KMO (2.0%-10.0% w/w), mixture of castor oil (CO):lemon essential oil (LO; 9:1) (1.0%-5.0% w/w), Tween 80 (1.0%-4.0% w/w), xanthan gum (0.5%-1.5% w/w), and deionized water (78.8%-94.8% w/w), on droplet size as a response were determined. RESULTS: Analysis of variance showed that the fitness of the quadratic polynomial fits the experimental data with F-value (2,479.87), a low P-value (P<0.0001), and a nonsignificant lack of fit. The optimized formulation of KMO-enriched nanoemulsion with desirable criteria was KMO (10.0% w/w), Tween 80 (3.19% w/w), CO:LO (3.74% w/w), xanthan gum (0.70% w/w), and deionized water (81.68% w/w). This optimum formulation showed good agreement between the actual droplet size (110.01 nm) and the predicted droplet size (111.73 nm) with a residual standard error <2.0%. The optimized formulation with pH values (6.28) showed high conductivity (1,492.00 µScm-1) and remained stable under accelerated stability study during storage at 4°C, 25°C, and 45°C for 90 days, centrifugal force as well as freeze-thaw cycles. Rheology measurement justified that the optimized formulation was more elastic (shear thinning and pseudo-plastic properties) rather than demonstrating viscous characteristics. In vitro cytotoxicity of the optimized KMO formulation and KMO oil showed that IC50 (50% inhibition of cell viability) value was >100 µg/mL. CONCLUSION: The survival rate of 3T3 cell on KMO formulation (54.76%) was found to be higher compared to KMO oil (53.37%) without any toxicity sign. This proved that the KMO formulation was less toxic and can be applied for cosmeceutical applications.


Assuntos
Emulsões/química , Hiperpigmentação/tratamento farmacológico , Nanopartículas/ultraestrutura , Óleos/química , Ácido Oleico/uso terapêutico , Pironas/uso terapêutico , Água/química , Células 3T3 , Análise de Variância , Animais , Morte Celular/efeitos dos fármacos , Camundongos , Nanopartículas/química , Tamanho da Partícula , Pironas/toxicidade , Reprodutibilidade dos Testes , Solubilidade , Fatores de Tempo
8.
Toxicol Lett ; 265: 9-16, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27866977

RESUMO

Qing Ye Dan (QYD) is the whole plant of Swertia mileensis and used in Chinese folk medicine for the treatment of prostatitis, benign prostatic hyperplasia (BPH) and so on. This study was to investigate the effects of QYD and its main component swertiamarin on BPH induced by testosterone in rats. The prostatic expressions of vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), basic fibroblast growth factor (ßFGF) and proliferating cell nuclear antigen (PCNA) were detected by immunohistochemistry assay. Prostatic levels of oxidative stress and inflammatory-related factors were also analyzed. Additionally, the prostatic expressions of androgen receptor (AR), estrogen receptor (ER)-α, ER-ß, hypoxia-inducible factor (HIF)-1α, B-cell CLL/lymphoma (Bcl)-2 and Bcl-2-associated X protein (Bax) were measured by western blot. The epithelial-mesenchymal transition (EMT) associated factors were evaluated by quantitative RT-PCR. It showed that QYD and swertiamarin ameliorated the testosterone-induced prostatic hyperplasia and collagen deposition, attenuated the over-expressions of HIF-1α, VEGF, EGF, ßFGF, PCNA, AR and ER-α, reduced the ratio of Bcl-2/Bax, enhanced the expression of ER-ß, inhibited the oxidative stress and local inflammation, as well as relieved prostatic EMT. It suggested that QYD and swertiamarin had prostatic protective potential against BPH.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Glucosídeos Iridoides/uso terapêutico , Hiperplasia Prostática/prevenção & controle , Pironas/uso terapêutico , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/toxicidade , Antioxidantes/administração & dosagem , Antioxidantes/isolamento & purificação , Antioxidantes/toxicidade , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/toxicidade , Transição Epitelial-Mesenquimal/imunologia , Feminino , Glucosídeos Iridoides/administração & dosagem , Glucosídeos Iridoides/isolamento & purificação , Glucosídeos Iridoides/toxicidade , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Próstata/efeitos dos fármacos , Próstata/imunologia , Próstata/metabolismo , Próstata/patologia , Hiperplasia Prostática/induzido quimicamente , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Pironas/administração & dosagem , Pironas/isolamento & purificação , Pironas/toxicidade , Ratos Wistar , Swertia/química , Testosterona/administração & dosagem , Testosterona/farmacologia , Testes de Toxicidade
9.
Nat Prod Commun ; 10(7): 1243-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26411021

RESUMO

6,8,9-Trihydroxy-2-methyl-2H-naphtho[2,3-b]pyran-5,10-dion, a pigment of the sea urchin Echinothrix diadema, and six analogs were synthesized. The cytotoxic activity and contraceptive properties of the synthesized pyranonaphthazarins have been investigated using the sperm and eggs of the sea urchin Strongylocentrotus intermedius.


Assuntos
Anticoncepcionais/síntese química , Naftoquinonas/química , Pigmentos Biológicos/química , Pironas/síntese química , Ouriços-do-Mar/química , Animais , Anticoncepcionais/toxicidade , Masculino , Naftoquinonas/toxicidade , Óvulo/efeitos dos fármacos , Pigmentos Biológicos/toxicidade , Pironas/análise , Pironas/toxicidade , Espermatozoides/efeitos dos fármacos
10.
Chem Res Toxicol ; 27(10): 1871-6, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25185080

RESUMO

Anxiolytic kava products have been associated with rare but severe hepatotoxicity in humans. This adverse potential has never been captured in animal models, and the responsible compound(s) remains to be determined. The lack of such knowledge greatly hinders the preparation of a safer kava product and limits its beneficial applications. In this study we evaluated the toxicity of kava as a single entity or in combination with acetaminophen (APAP) in C57BL/6 mice. Kava alone revealed no adverse effects for long-term usage even at a dose of 500 mg/kg bodyweight. On the contrary a three-day kava pretreatment potentiated APAP-induced hepatotoxicity, resulted in an increase in serum ALT and AST, and increased severity of liver lesions. Chalcone-based flavokawains A (FKA) and B (FKB) in kava recapitulated its hepatotoxic synergism with APAP while dihydromethysticin (DHM, a representative kavalactone and a potential lung cancer chemopreventive agent) had no such effect. These results, for the first time, demonstrate the hepatotoxic risk of kava and its chalcone-based FKA and FKB in vivo and suggest that herb-drug interaction may account for the rare hepatotoxicity associated with anxiolytic kava usage in humans.


Assuntos
Acetaminofen/toxicidade , Chalcona/análogos & derivados , Flavonoides/toxicidade , Kava/química , Fígado/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Chalcona/química , Chalcona/toxicidade , Sinergismo Farmacológico , Feminino , Flavonoides/química , Kava/metabolismo , Fígado/enzimologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Pironas/química , Pironas/toxicidade
11.
Mycotoxin Res ; 28(2): 89-96, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-23606046

RESUMO

An isolated occurrence of Fusarium head blight (FHB) of wheat was detected in the south-west region of Western Australia during the 2003 harvest season. The molecular identity of 23 isolates of Fusarium spp. collected from this region during the FHB outbreak confirmed the associated pathogens to be F. graminearum, F. acuminatum or F. tricinctum. Moreover, the toxicity of their crude extracts from Czapek-Dox liquid broth and millet seed cultures to brine shrimp (Artemia franciscana) was associated with high mortality levels. The main mycotoxins detected were type B trichothecenes (deoxynivalenol and 3-acetyldeoxynivalenol), enniatins, chlamydosporol and zearalenone. This study is the first report on the mycotoxin profiles of Fusarium spp. associated with FHB of wheat in Western Australia. This study highlights the need for monitoring not just for the presence of the specific Fusarium spp. present in any affected grain but also for their potential mycotoxin and other toxic secondary metabolites.


Assuntos
Grão Comestível/microbiologia , Fusarium/isolamento & purificação , Micotoxinas/biossíntese , Doenças das Plantas/microbiologia , Triticum/microbiologia , Animais , Artemisia/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Depsipeptídeos/análise , Depsipeptídeos/biossíntese , Depsipeptídeos/toxicidade , Fusarium/classificação , Fusarium/metabolismo , Micotoxinas/análise , Micotoxinas/toxicidade , Pironas/análise , Pironas/metabolismo , Pironas/toxicidade , Tricotecenos/análise , Tricotecenos/biossíntese , Tricotecenos/toxicidade , Austrália Ocidental , Zearalenona/análise , Zearalenona/biossíntese , Zearalenona/toxicidade
12.
Bioorg Med Chem Lett ; 21(8): 2445-9, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21397499

RESUMO

In this study, we synthesized hydroxy and/or alkoxy substituted phenyl-benzo[d]thiazole derivatives using substituted benzaldehydes and 2-aminothiophenol in MeOH. The structures of these compounds were established by (1)H and (13)CNMR and mass spectral analyzes. All synthesized compounds were evaluated for their mushroom tyrosinase inhibition activity. Out the 12 generated compounds, 2a and 2d exhibited much higher tyrosinase inhibition activity (45.36-73.07% and 49.94-94.17% at 0.01-20 µM, respectively) than kojic acid (9.29-50.80% at 1.25-20 µM), a positive control. The cytotoxicity of 2a and 2d was evaluated using B16 cells and the compounds were found to be nontoxic. Compounds 2a and 2d were also demonstrated to be potent mushroom tyrosinase inhibitors, displaying IC(50) values of 1.14±0.48 and 0.01±0.0002 µM, respectively, compared with kojic acid, which has an IC(50) value of 18.45±0.17 µM. We also predicted the tertiary structure of tyrosinase, simulated the docking with compounds 2a and 2d and confirmed that the compounds strongly interact with mushroom tyrosinase residues. Kinetic plots showed that 2a and 2d are competitive tyrosinase inhibitors. Substitutions with a hydroxy group at R(3) or both R(3) and R(1) of the phenyl ring indicated that these groups play a major role in the high binding affinity to tyrosinase. We further found that compounds 2a and 2d inhibit melanin production and tyrosinase activity in B16 cells. These results may assist in the development of new potent tyrosinase inhibitors against hyperpigmentation.


Assuntos
Benzotiazóis/uso terapêutico , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Animais , Benzotiazóis/química , Benzotiazóis/toxicidade , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Simulação por Computador , Cinética , Melaninas/biossíntese , Melanoma Experimental/tratamento farmacológico , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Pironas/toxicidade
13.
Eur J Med Chem ; 45(9): 4089-95, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20591538

RESUMO

A series of 6-chloromethyl-3-hydroxy-2-substituted 4H-pyran-4-one derivatives were synthesized and tested for their antimicrobial and antiviral activities. Mannich base derivatives were prepared through the reaction of substituted piperazine or piperidine derivatives on chlorokojic acid and formaline. The structures of the synthesized compounds were confirmed by IR, (1)H and (13)C NMR, ESI-MS, and elemental analysis. According to the activity studies, compounds 2-7 (MIC: 1-2 microg/mL) were found to be highly active against Bacillus subtilis and Staphylococcus aureus, while compounds 3, 5 and 6 showed significant activity against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii. Also, compounds 2-7 were more remarkably active against Candida albicans and Candida parapsilosis (MIC: 4-8 microg/mL). Additionally, compound 2 was the most active one against RNA virus PI-3.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antivirais/química , Antivirais/farmacologia , Pironas/química , Pironas/farmacologia , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/toxicidade , Antivirais/síntese química , Antivirais/toxicidade , Bactérias/efeitos dos fármacos , Linhagem Celular , Chlorocebus aethiops , Avaliação Pré-Clínica de Medicamentos , Fungos/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Bases de Mannich/química , Testes de Sensibilidade Microbiana , Vírus da Parainfluenza 3 Humana/efeitos dos fármacos , Pironas/síntese química , Pironas/toxicidade , Análise Espectral , Células Vero
14.
J Toxicol Sci ; 32(2): 143-59, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17538239

RESUMO

Kojic acid (KA) has been widely used as a quasi-drug ingredient. Possible promotion activity of KA was suggested on livers of mouse and rat by findings obtained in genotoxicity and carcinogenicity studies performed thus far. Therefore, in order to examine safety as a quasi-drug ingredient, we investigated the presence of initiation activity in rat liver and the photo-genotoxicity and carcinogenicity in mouse skin. In medium-term carcinogenesis test in rats, 2.0% KA was orally given to F344/DuCrj rats for 4 weeks of the initiation period, followed by the combination of partial hepatectomy and treatment with a hepatocarcinogenesis promoter, phenobarbital (PB). As a result, glutathione S-transferase placental form (GST-P) positive foci of 0.2 mm or more in diameter in the KA group, which is usually used in determination of pre-cancerous lesions, did not increase significantly in both numbers and areas compared with those of the non-initiated controls. In the concurrent analysis, however, numbers of GST-P-positive foci of two cells or more and 0.1 mm or more in diameter increased slightly, and possible weak initiation activity of KA was equivocal. However, considering the known fact that KA exerts promotion activity in the liver of F344 rats by long-term dietary administration, it was suggested that the observed slight increase of the numbers of GST-P-positive foci in rat liver was the effect of promotion activity of KA rather than the initiation activity. In DNA adducts formation assay in a rat liver, no clear adducts derived from KA were detected in male F344/DuCrj rats administered 0.5% or 2% KA orally, and KA was considered not to form DNA adducts in rat liver. In the in vitro photo-reverse mutation assay with bacteria, KA exerted weak photo-mutagenicity. Furthermore, in chromosome aberration study in Chinese hamster lung cells (CHL/IU cells) with UV irradiation, KA induced chromosome aberration at high-dose (1.4 mg/mL) treatment with UV irradiation, but was negative without UV irradiation. However, in the in vivo photo-micronucleus study in mouse, in which 1.0 or 3.0% KA containing cream was applied twice to the back of the animals with a 24-hr interval, KA did not induce micronuclei in mouse epidermal cells. Based on these results, it is considered that the risk of KA to exert photo-carcinogenicity is quite low in the skin. In skin carcinogenesis bioassay for initiation-promotion potential, 3.0% KA cream formulation was applied to the back of the mouse for 1 week (once a day, total 7 times) and for 19 weeks (5 times a week, total 95 times) during the initiation and the promotion stages, respectively. No skin nodules were observed in any animal skins formed due to KA treatment given in either stage. Therefore, KA is considered not to possess initiation nor promotion activity of skin carcinogenesis. Furthermore, from the above findings, it is suggested that KA is virtually safe as a quasi-drug ingredient.


Assuntos
Antioxidantes/toxicidade , Carcinógenos/toxicidade , Mutagênicos/toxicidade , Micotoxinas/toxicidade , Pironas/toxicidade , Pele/efeitos dos fármacos , Administração Oral , Animais , Antioxidantes/química , Células CHO , Testes de Carcinogenicidade , Carcinógenos/química , Cricetinae , Cricetulus , Adutos de DNA/química , Dermatite Fototóxica , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Testes para Micronúcleos , Mutagênicos/química , Micotoxinas/química , Pironas/química , Ratos , Ratos Endogâmicos F344 , Pele/patologia , Pele/efeitos da radiação , Neoplasias Cutâneas
15.
Phytomedicine ; 13(3): 181-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16428026

RESUMO

We extracted and isolated three natural styryl lactones from Goniothalamus griffithii Hook f. Thoms and investigated their cytotoxicity on a panel of three hepatocyte cell lines, HepG2, drug resistant HepG2 (HepG2-R) and primary cultured normal mice hepatocyte in order to find candidates of potential anti-cancer drugs which have low toxicity on normal cells and high effect on tumors or drug resistant tumors. All the three styryl lactones showed evident cytotoxic activities on both HepG2 and HepG2-R cell lines; however, gonithalamin and goniodiol shows less toxicity on normal mice hepatocyte as the IC(50) values of them on normal mice hepatocyte were about three times of that on HepG2. Morphological observation and cell cycle analysis were employed to elucidate the mechanisms of cytotoxicity of the tested compounds. Many apoptotic cells were observed in gonithalamin- and altholactone-treated cells, whereas, cells with chromosomes gathered at the equator were easily found in goniodiol-treated cultures. The analysis of cell cycle showed that G(2)/M arrest contributed to goniothalimin- and gonidiol-caused cell death and apoptosis was the cause of gonithalamin- and altholactone-induced cell death. Our results suggest that the three styryl lactones may be prospectively developed into anti-tumor drugs, especially on treating drug-resistance tumor after structure modification.


Assuntos
Furanos/toxicidade , Hepatócitos/efeitos dos fármacos , Lactonas/toxicidade , Pironas/toxicidade , Animais , Annonaceae/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Citometria de Fluxo/métodos , Furanos/química , Furanos/farmacologia , Harringtoninas/farmacologia , Humanos , Lactonas/química , Lactonas/farmacologia , Camundongos , Pironas/química , Pironas/farmacologia , Testes de Toxicidade/métodos
16.
Toxicol Sci ; 79(1): 106-11, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14737001

RESUMO

Kava herbal supplements have been recently associated with acute hepatotoxicity, leading to the ban of kava products in approximately a dozen countries around the world. It is suspected that some alkaloids from aerial kava may have contributed to the problem. Traditionally, Pacific Islanders use primarily the underground parts of the shrub to prepare the kava beverage. However, some kava herbal supplements may contain ingredients from aerial stem peelings. The aim of this study was to test the in vitro effects of a major kava alkaloid, pipermethystine (PM), found mostly in leaves and stem peelings, and kavalactones such as 7,8-dihydromethysticin (DHM) and desmethoxyyangonin (DMY), which are abundant in the roots. Exposure of human hepatoma cells, HepG2, to 100 microM PM caused 90% loss in cell viability within 24 h, while 50 microM caused 65% cell death. Similar concentrations of kavalactones did not affect cell viability for up to 8 days of treatment. Mechanistic studies indicate that, in contrast to kavalactones, PM significantly decreased cellular ATP levels, mitochondrial membrane potential, and induced apoptosis as measured by the release of caspase-3 after 24 h of treatment. These observations suggest that PM, rather than kavalactones, is capable of causing cell death, probably in part by disrupting mitochondrial function. Thus, PM may contribute to rare but severe hepatotoxic reactions to kava.


Assuntos
Alcaloides/toxicidade , Kava/toxicidade , Lactonas/toxicidade , Piridonas/toxicidade , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Apoptose/efeitos dos fármacos , Caspases/efeitos dos fármacos , Linhagem Celular Tumoral , Suplementos Nutricionais/toxicidade , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Kava/química , Kava/metabolismo , Lactonas/química , Lactonas/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta/química , Caules de Planta/efeitos adversos , Caules de Planta/química , Piridonas/química , Piridonas/isolamento & purificação , Pironas/química , Pironas/metabolismo , Pironas/toxicidade , Fatores de Tempo
17.
Phytomedicine ; 10 Suppl 4: 68-73, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12807347

RESUMO

Kava pyrones have been sold in Germany as OTC anxiolytics until June 2002, when all preparations with a kava pyrone content of more than 10(-4) of a homeopathic stock solution were withdrawn. Other countries in which kava pyrones have been used as anxiolytics, namely GB and the USA, have not followed suit. Kava pyrone anxiolytics have been positively reviewed by the Cochrane Collaboration; also newer German clinical studies have indicated pharmacological anxiolysis at the recommended doses. To use the first choice of treatment, psychotherapy, for all uncomplicated cases of pathological fear does not appear to be realistic. Current data about kava pyrone toxicity are unclear. Judging from the few well documented cases of kava pyrone hepatotoxicity (appr. 2 out of 36) in Germany and Switzerland, an immunologically mediated idiosyncratic mechanism appears to be most likely, especially at higher doses, whereas a direct toxic mechanism is much less likely. No direct results are available for the incidence of kava pyrone-related adverse drug effects. From spontaneously reported cases the incidences of adverse drug reactions cannot be obtained, a rough estimation indicates the incidence of hepatotoxicity to be comparable to those of benzodiazepines. Taken together, the withdrawal of kava pyrone-based anxiolytics appears to be an ill founded over-reaction given the lack of superior therapeutic alternatives. Neither the case evaluations presented by the BfArM (Bundesamt für Arzneimittel und Medizinprodukte = Federal Office for Drugs and Medical Products) nor the complete rejection of proof for therapeutic efficacy of kava pyrone anxiolytics are scientifically well founded.


Assuntos
Ansiolíticos/toxicidade , Kava , Fitoterapia , Extratos Vegetais/toxicidade , Sistemas de Notificação de Reações Adversas a Medicamentos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Interações Medicamentosas , Alemanha , Humanos , Pironas/toxicidade , Estados Unidos
18.
Neurobiol Dis ; 8(5): 764-73, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11592846

RESUMO

Direct (intracisternal) injection of aluminum complexes into rabbit brain results in a number of similarities with the neuropathological and biochemical changes observed in Alzheimer's disease and provides the opportunity to assess early events in neurodegeneration. This mode of administration induces cytochrome c release from mitochondria, a decrease in Bcl-2 in both mitochondria and endoplasmic reticulum, Bax translocation into mitochondria, activation of caspase-3, and DNA fragmentation. Coadministration of glial cell neuronal-derived factor (GDNF) inhibits these Bcl-2 and Bax changes, upregulates Bcl-XL, and abolishes the caspase-3 activity. Furthermore, treatment with GDNF dramatically inhibits apoptosis, as assessed by the TUNEL technique for detecting DNA damage. Treatment with GDNF may represent a therapeutic strategy to reverse the neuronal death associated with Alzheimer's disease and may exert its effect on apoptosis-regulatory proteins.


Assuntos
Apoptose/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Mitocôndrias/metabolismo , Fatores de Crescimento Neural , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/uso terapêutico , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Caspase 3 , Caspases/metabolismo , Cisterna Magna , Grupo dos Citocromos c/metabolismo , Fragmentação do DNA , Avaliação Pré-Clínica de Medicamentos , Retículo Endoplasmático/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Genes bcl-2 , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Hipocampo/metabolismo , Hipocampo/patologia , Marcação In Situ das Extremidades Cortadas , Injeções , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/farmacologia , Neurônios/metabolismo , Neurônios/patologia , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/toxicidade , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Pironas/administração & dosagem , Pironas/toxicidade , Coelhos , Proteína X Associada a bcl-2 , Proteína bcl-X
19.
J Antibiot (Tokyo) ; 50(4): 314-7, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9186556

RESUMO

Five novel cytotoxic antibiotics, NF00659A1 (1), A2 (2), A3 (3), B1 (4) and B2 (5) were discovered. They were isolated from a culture mycelium of Aspergillus sp. These compounds were proved to have 4,5-seco-tricyclic diterpene alpha-pyrone structure by spectroscopic analyses. They showed potent antitumor activities against human ovarian carcinoma A2780 and human colorectal adenocarcinoma SW480 cells, but did not show any antimicrobial activities at 1,000 micrograms/ml against Gram-positive and Gram-negative bacteria, yeasts and fungi.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Diterpenos/isolamento & purificação , Inseticidas/isolamento & purificação , Neoplasias Ovarianas/tratamento farmacológico , Pironas/isolamento & purificação , Animais , Antibióticos Antineoplásicos/toxicidade , Culex/efeitos dos fármacos , Diterpenos/uso terapêutico , Diterpenos/toxicidade , Feminino , Fermentação , Humanos , Inseticidas/farmacologia , Inseticidas/toxicidade , Camundongos , Testes de Sensibilidade Microbiana , Mariposas/efeitos dos fármacos , Pironas/uso terapêutico , Pironas/toxicidade , Células Tumorais Cultivadas/efeitos dos fármacos
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