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1.
PLoS One ; 13(5): e0196667, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29750792

RESUMO

Schistosomiasis is a disease caused by parasites of the genus Schistosoma, currently affecting more than 200 million people. Among the various species of this parasite that infect humans, S. mansoni is the most common. Pharmacological treatment is limited to the use of a single drug, praziquantel (PZQ), despite reports of parasite resistance and low efficacy. It is therefore necessary to investigate new potential schistosomicidal compounds. In this study, we tested the efficacy of epiisopilosine (EPIIS) in a murine model of schistosomiasis. A single dose of EPIIS (100 or 400 mg/kg) administered orally to mice infected with adult S. mansoni resulted in reduced worm burden and egg production. The treatment with the lower dose of EPIIS (100 mg/kg) significantly reduced total worm burden by 60.61% (P < 0.001), as well as decreasing hepatosplenomegaly and egg excretion. Scanning electron microscopy revealed morphological changes in the worm tegument after treatment. Despite good activity of EPIIS in adult S. mansoni, oral treatment with single dose of EPIIS 100 mg/kg had only moderate effects in mice infected with juvenile S. mansoni. In addition, we performed cytotoxicity and toxicological studies with EPIIS and found no in vitro cytotoxicity (in HaCaT, and NIH-3T3 cells) at a concentration of 512 µg/mL. We also performed in silico analysis of toxicological properties and showed that EPIIS had low predicted toxicity. To confirm this, we investigated systemic acute toxicity in vivo by orally administering a 2000 mg/kg dose to Swiss mice. Treated mice showed no significant changes in hematological, biochemical, or histological parameters compared to non-treated animals. Epiisopilosine showed potential as a schistosomicidal drug: it did not cause acute toxicity and it displayed an acceptable safety profile in the animal model.


Assuntos
Alcaloides/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Contagem de Ovos de Parasitas/métodos , Praziquantel/farmacologia , Esquistossomose mansoni/parasitologia , Esquistossomicidas/farmacologia
2.
Food Res Int ; 105: 184-196, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433206

RESUMO

This study investigated a lycopene-rich extract from red guava (LEG) for its chemical composition using spectrophotometry, mass spectrometry, attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), and computational studies. The cytotoxic activity of LEG and the underlying mechanism was studied in human breast adenocarcinoma cells (MCF-7), murine fibroblast cells (NIH-3T3), BALB/c murine peritoneal macrophages, and sheep blood erythrocytes by evaluating the cell viability with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and flow cytometry. Spectrophotometry analysis showed that LEG contained 20% of lycopene per extract dry weight. Experimental and theoretical ATR-FTIR suggests the presence of lycopene, whereas MS/MS spectra obtained after fragmentation of the molecular ion [M]+• of 536.4364 show fragment ions at m/z 269.2259, 375.3034, 444.3788, and 467.3658, corroborating the presence of lycopene mostly related to all-trans configuration. Treatment with LEG (1600 to 6.25µg/mL) for 24 and 72h significantly affected the viability of MCF-7 cells (mean half maximal inhibitory concentration [IC50]=29.85 and 5.964µg/mL, respectively) but not NIH-3T3 cells (IC50=1579 and 911.5µg/mL, respectively). Furthermore LEG at concentrations from 800 to 6.25µg/mL presented low cytotoxicity against BALB/c peritoneal macrophages (IC50≥800µg/mL) and no hemolytic activity. LEG (400 and 800µg/mL) caused reduction in the cell proliferation and induced cell cycle arrest, DNA fragmentation, modifications in the mitochondrial membrane potential, and morphologic changes related to granularity and size in MCF-7 cells; however, it failed to cause any significant damage to the cell membrane or display necrosis or traditional apoptosis. In conclusion, LEG was able to induce cytostatic and cytotoxic effects on breast cancer cells probably via induction of an apoptotic-like pathway.


Assuntos
Apoptose/efeitos dos fármacos , Licopeno/análise , Licopeno/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Psidium/química , Animais , Ciclo Celular/efeitos dos fármacos , Membrana Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas em Tandem
3.
Food Res Int ; 99(Pt 2): 959-968, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28847433

RESUMO

This study investigated the anti-inflammatory activity of the extract (LEG) and purified (LPG) lycopene from guava (Psidium guajava L.), as well as some mechanisms possibly involved in this effect. The anti-inflammatory activity was initially assessed using paw edema induced by Carrageenan, Dextran, Compound 48/80, Histamine and Prostaglandin E2 in Swiss mice. A peritonitis model was used to evaluate neutrophil migration, the activity of myeloperoxidase (MPO) and reduced glutathione (GSH) concentration; while the effect on the expression of iNOS, COX-2 and NF-κB, was assessed by immunohistochemistry analysis. Results showed that oral and intraperitoneal administration of LEG and LPG inhibited inflammation caused by carrageenan. LPG (12.5mg/kg p.o.) significantly inhibited the edema formation induced by different phlogistic agents and immunostaining for iNOS, COX-2 and NF-κB. Leukocytes migration in paw tissue and peritoneal cavity was reduced, as well as MPO concentration, whereas GSH levels increased. Thus, lycopene-rich extract from red guava has beneficial effect on acute inflammation, offering protection against the consequences of oxidative stress by downregulating inflammatory mediators and inhibiting gene expression involved in inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Edema/prevenção & controle , Inflamação/prevenção & controle , Leucócitos/efeitos dos fármacos , Peritonite/prevenção & controle , Extratos Vegetais/farmacologia , Psidium , Animais , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Edema/imunologia , Edema/metabolismo , Feminino , Frutas , Glutationa/metabolismo , Inflamação/imunologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Masculino , Camundongos , NF-kappa B/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peritonite/imunologia , Peritonite/metabolismo , Peroxidase/metabolismo , Extratos Vegetais/isolamento & purificação , Psidium/química
4.
J Agric Food Chem ; 59(16): 8901-7, 2011 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-21790134

RESUMO

The infusion of aerial parts of Ilex paraguariensis is widely consumed. Its antioxidant activity suggests an important role of this plant in the treatment/prevention of oxidative stress related diseases. Plant extract active compounds are frequently found in esterified form that may be poorly absorbed. Hydrolysis of the extract is a possible approach to increase its bioavailability. The aim of this study was to perform a phytochemical analysis and evaluate in rats the plasma concentration and tissue distribution of antioxidant compounds in the hydroethanolic extract of Ilex paraguariensis, before and after enzymatic hydrolysis. Both extracts presented high antioxidant activity and phenolic content. Rats given single or repeated doses of the hydrolyzed extract showed increased plasma antioxidant activity and higher plasma levels of caffeic acid. However, no changes of endogenous antioxidants were observed. In conclusion, hydrolysis of the extract of Ilex paraguariensis is a strategy to improve its bioavailability and in vivo antioxidant activity.


Assuntos
Antioxidantes/análise , Ilex paraguariensis/química , Extratos Vegetais/química , Animais , Ácidos Cafeicos/sangue , Etanol , Hidrólise , Masculino , Fenóis/análise , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Folhas de Planta/química , Ácido Quínico/análogos & derivados , Ácido Quínico/sangue , Ratos , Ratos Wistar , Água
5.
Photochem Photobiol ; 82(2): 439-42, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16613496

RESUMO

Exposure to UV radiation up-regulates the synthesis of matrix metalloproteinases (MMPs), a group of matrix-degrading enzymes. MMPs are regarded as promising therapeutic targets and the development of effective inhibitors is an important research focus. The plant Pothomorphe umbellata has been shown to exert a potent antioxidant activity on the skin and to delay the onset and reduce the incidence of UVB-induced chronic skin damage. The aim of the present study was to determine the effect of P. umbellata ethanolic root extract on MMP-2 and MMP-9. The in vitro inhibition of MMP-2 and MMP-9 was measured by gelatin zymography in the presence of different concentrations of P. umbellata extract, as well as in the presence of its isolated active principle 4-nerolidylcatechol (4-NC). The inhibitory effect of the P. umbellata extract was stronger than that of 4-NC. Gelatin zymography and histological analysis revealed that P. umbellata was able to inhibit constitutive MMP-9 activity in vivo in mice sacrificed 2 h after UVB irradiation. The intensity of the MMP-2 band was unchanged. Our data contribute to the elucidation of the mechanism of prevention of photoaging by P. umbellata and may provide a rational basis for the use of this plant in prophylaxis against and treatment of skin cancer.


Assuntos
Inibidores de Metaloproteinases de Matriz , Piperaceae/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Protetores contra Radiação/farmacologia , Pele/enzimologia , Animais , Catecóis/isolamento & purificação , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Gelatina/química , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Pelados , Fitoterapia/métodos , Extratos Vegetais/química , Lesões Experimentais por Radiação/patologia , Lesões Experimentais por Radiação/prevenção & controle , Fatores de Tempo , Raios Ultravioleta
6.
Int J Pharm ; 303(1-2): 125-31, 2005 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-16129576

RESUMO

Due to its antioxidant and photoprotective properties, Pothomorphe umbellata is a promising candidate for use in cosmetic and pharmaceutical formulations. These properties arise from the presence of 4-nerolidylcathecol (4-NC), a polyphenolic compound isolated from P. umbellata roots. This study investigates its photostability properties, as well as the chemical and the in vitro sun protection factor (SPF) of P. umbellata root extract in a gel formulation. A high performance liquid chromatography method was used to evaluate the chemical stability using 4-NC as marker at 5, 25 and 45 degrees C for 103 days. The photostability and the sun protection factor were analyzed by ultraviolet (UV) spectophotometry using samples irradiated with UVB lamp. No significant difference of the 4-NC concentration was found in formulations stored at 5 and 25 degrees C. All samples stored at 45 degrees C, however, showed degradation of gel structure. After 2h of UVB exposure, there was no change in the absorption profile of 4-NC. The sun protection factor of P. umbellata root extract gel to final concentration of 0.1% 4-NC was not expressive (SPF=3.35+/-0.02), suggesting the predominance of its antioxidant activity.


Assuntos
Piperaceae/química , Extratos Vegetais/química , Protetores Solares/química , Resinas Acrílicas , Catecóis/análise , Estabilidade de Medicamentos , Géis , Fotoquímica , Extratos Vegetais/efeitos da radiação , Raízes de Plantas/química , Espectrofotometria , Protetores Solares/análise , Protetores Solares/efeitos da radiação , Temperatura , Fatores de Tempo , Raios Ultravioleta
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