Protective Effect of Baccharis trimera Extract on Acute Hepatic Injury in a Model of Inflammation Induced by Acetaminophen

Background. Acetaminophen (APAP) is a commonly used analgesic and antipyretic. When administered in high doses, APAP is a clinical problem in the US and Europe, often resulting in severe liver injury and potentially acute liver failure. Studies have demonstrated that antioxidants and anti-inflammatory agents effectively protect against the acute hepatotoxicity induced by APAP overdose. Methods. The present study attempted to investigate the protective effect of B. trimera against APAP-induced hepatic damage in rats. The liver-function markers ALT and AST, biomarkers of oxidative stress, antioxidant parameters, and histopathological changes were examined. Results. The pretreatment with B. trimera attenuated serum activities of ALT and AST that were enhanced by administration of APAP. Furthermore, pretreatment with the extract decreases the activity of the enzyme SOD and increases the activity of catalase and the concentration of total glutathione. Histopathological analysis confirmed the alleviation of liver damage and reduced lesions caused by APAP. Conclusions. The hepatoprotective action of B. trimera extract may rely on its effect on reducing the oxidative stress caused by APAP-induced hepatic damage in a rat model. General Significance. These results make the extract of B. trimera a potential candidate drug capable of protecting the liver against damage caused by APAP overdose

Developmnet and validation of bioanalytical method for pharmacokinetic disposition of a binary mixture of pentacyclic triterpenes and their metabolites in vivo

A mistura triterpênica ¤ e ß- amirinas é comumente encontrada em quantidades significativas em espécies do gênero Protium (Burseraceae) e possuem reconhecidas atividades anti-inflamatória, hepatoprotetora, gastroprotetora e analgésica, dentre outras. Entretanto, pouco se sabe sobre sua farmacocinética e metabolismo. Neste sentido, esta tese teve o objetivo de desenvolver metodologias bioanalíticas para determinar a farmacocinética e a eliminação de ? e ?-amirinas isoladas de P. spruceanum bem como avaliar o metabolismo in vitro destes triterpenos. A mistura de ¤ e ß-amirinas foi isolada em grau de pureza cromatográfica acima de 99%. Foi desenvolvida e caracterizada uma nanoemulsão do tipo O/A contendo ¤ e ß-amirinas a fim de viabilizar a administração por vias oral e endovenosa e realizar os estudos de disposição cinética dessas substâncias em camundongos. O tamanho médio das partículas da nanoemulsão foi de 103,5 ± 0,44 nm, com porcentagem de encapsulação de acima de 99%. Os estudos de liberação in vitro mostraram baixa taxa de liberação após 24 horas. A avaliação da disposição cinética de ? e ?-amirinas em camundongos mostrou que após administração oral a suspensão de CMC não foi absorvida, entretanto a nanoemulsão contendo as substancias foi absorvida e a biodisponibilidade oral de ¤ e ß-amirinas foi de 1,03 ± 0,08 e 1,56 ± 0,24%, respectivamente. O Vd foi elevado e a T1/2 foi de 2,61±0,15 e 2,57±0,07 horas, respectivamente. O ClB mostrou-se elevado, comparado ao ClR. Após administração oral da nanoemulsão, praticamente toda a mistura foi eliminada inalterada nas fezes devido a baixa absorção. Entretanto, após administração endovenosa cerca de 50% da mistura foi eliminada inalterada pela via biliar. Estudos de eliminação renal de ¤ e ß-amirinas mostraram que apenas cerca de 0,2% das substâncias foram eliminadas por via renal após administração endovenosa. O fenômeno Flip-Flop ocorreu para a via extravascular utilizada. Os resultados da eliminação parcial e de baixa liberação in vitro sugerem que após administração endovenosa da nanoemulsão pode ocorrer acúmulo extravascular dos compostos, corroborando com altos Vd. As reações biomiméticas de oxidação de ¤ e ß-amirinas mostraram baixa taxa degradação. Apenas um metabólito putativo foi encontrado, entretanto, não foi possível observá-lo nas matrizes biológicas analisadas.The triterpene mixture of ¤ and ß-amyrins is generally found in significative amounts in Protium species (Burseraceae). They have known biological activities as anti-inflammatory, hepatoprotective, gastroprotective and antinociceptive effects among others. However, their pharmacokinetics and metabolism are practically unknown. The purpose of this thesis was to develop bioanalytical methodologies to perform pharmacokinetic and elimination studies of ¤ and ß-amyrins from P. spruceanum as well as to evaluate in vitro metabolism of these triterpenes. The mixture ¤ and ß-amyrins was isolated with chromatography purity above 99%. One ¤ and ß-amyrins loaded O/W nanoemulsion was developed and characterized to enable the intravenous and oral administration and to performed pharmacokinetic studies of these compounds in mice. The average particle size was 103.5 ± 0.44 nm and the encapsulation efficiency was higher than 99%. In vitro release study demonstrated low release rater after 24 hours. The pharmacokinetics studies of ? and ?-amyrins indicated CMC suspension was not absorbed, however ¤ and ß-amyrins loaded O/W nanoemulsion was poorly absorved and bioavailability was 1.03 ± 0.08 and 1.56 ± 0.24% respectively. The Vd was high and T1/2 was 2.61 ± 0.15 e 2.57± 0.07 hours respectively. The ClB was high compared to ClR. After oral administration almost all ¤ and ß-amyrins were eliminated unchanged in faeces due to low absorption. However, after intravenous administration about 50% was excluded unchanged by biliar excretion pathway. Studies of ¤ and ß-amyrins renal elimination directed only 0.2 % were removed unchanged by renal pathway after intravenous administration. The Flip-Flop phenomenon was happen when ¤ and ß- amyrins was dispensed by extravascular via. The partial biliar excretion in vivo and low release rate in vitro suggests ¤ and ß-amyrins could be stored after nanoemulsion intravenous administration confirming high Vd. The biomimetic reactions of oxidation of ¤ and ß-amyrins showed low degradation rate and only one metabolite was found however it was not detected in biological samples

Estudo biomonitorado para avaliação das atividades antiinflamatória e analgésica da folhas da espécie Protium spruceanum (Benth) Engler. (Burseraceae).

Nesta dissertação foi realizado o estudo biomonitorado das atividades analgésica e antiinflamatória in vivo e da propriedade antioxidante in vitro do extrato etanólico bruto (EEB) das folhas de Protium spruceanum (Benth.) Engler. Foram utilizados ensaios de detecção das principais classes de metabólitos secundários presentes no EEB e técnicas cromatográficas para isolamento de constituintes majoritários das frações mais ativas. Os teores de FT e de FVT foram determinados por métodos espectrométricos. As atividades farmacológicas in vivo foram avaliadas pelo método de edema de pata induzido por carragenina para determinar a atividade antiinflamatória e métodos de contorções abdominais induzidas por ácido acético, placa quente e formalina para determinação da atividade antinociceptiva. A toxicidade aguda foi determinada a fim de avaliar os efeitos tóxicos do EEB. Observou-se a presença de compostos fenólicos, taninos, flavonóides, saponinas, triterpenos, esteróides, xantonas e cumarinas. O constituinte majoritário encontrado na fração FHEX foi a mistura de α e β-amirinas. Nas frações FDCM e FMEOHF foram isolados três flavonóides, ainda em fase de identificação. Na determinação da propriedade antioxidante foram observados resultados significativos para EEB e frações FMEOH-1, FDCM e PDCM comparadas ao padrão de ácido gálico, onde FDCM apresentou melhor resultado. O EEB apresentou aproximadamente 18 % de compostos fenólicos e a fração FDCM apresentou maior teor de FVT. Na avaliação da atividade antiinflamatória foi possível observar atividade significativa para FHEX e FMEOH-1. Após o fracionamento de FMEOH-1, as frações FMEOH-F e FDCM apresentaram atividade significativa. Observouse também significativa atividade antinociceptiva para as frações FHEX e FMEOH-1 frente ao método de contorções abdominais. Pelo método de placa quente, o EEB, na maior dose administrada, foi capaz de aumentar o TL inicial após 60 minutos da administração, e após a partição, apenas a FHEX apresentou atividade antinociceptiva significativa. No modelo de formalina, o EEB e a FHEX apresentaram atividade antinociceptiva apenas na Fase II. As atividades analgésica central e periférica, e antiinflamatória da FHEX podem ser atribuídas a presença da mistura dos triterpenos α e β-amirina, principal constituinte desta fração. A atividade antiinflamatória das frações FMEOH-1, FMEOH-F e FDCM pode ser atribuída ao considerável teor de compostos fenólicos, principalmente flavonóides, nestas frações. Não foi possível estabelecer a DL50 em camundongos para a administração do EEB até a dose de 6 g/kg.The aim of this work was to perform the bioactivity study of analgesic and antiinflammatory activities in vivo and antioxidant property in vitro of crude ethanolic extract (EEB) from Protium spruceanum leaves. Were used for phytochemical screening tests to detect the main classes of secondary metabolites presents in the EEB and chromatographic techniques for isolation of the major constituents of the most active fractions. The content of FVT and FT were determined by spectroscopic methods. For evaluation of pharmacological activities in vivo was utilized paw edema induced by carrageenan method to determine the anti-inflammatory activity and methods of writhing induced by acetic acid, hot plate and formalin for determination of antinociceptive activity. The acute toxicity was determined to assess the toxic effects of EEB. The phytochemical screening revealed the presence of phenolic compounds, tannins, flavonoids, saponins, triterpenes, steroids, coumarins and xanthones. The major constituent found in FHEX fraction was a mixture of α and β-amyrin. In the fractions FDCM and FMEOH-F were isolated three flavonoids that are still being identified. Bether antioxidant properties were observed for EEB and the more polar fractions FMEOH-1, FDCM and PDCM compared to the standard gallic acid. FDCM showed the highest activity. The EEB showed approximately 18% of phenolics compounds and in FDCM was observed the highest level of FVT. FHEX and FMEOH-1 showed antiiflammatory activity and after fractionation, FMEOH-F and FDCM showed significant antiinflammatory activity. In the writhing test, both fractions, FHEX and FMEOH-1 presents significative activity. For the hot plate method the EEB, in the highest dose administered, has been able to increase the TL initial 60 minutes after the administration and after fractionation, only FHEX showed significative activity. For the formalin method, the EEB and FHEX showed antinociceptive activity only in Phase II. The central and peripheral analgesic and anti-inflammatory of FHEX can be attributed to the presence of α and β- amyrin, the main constituent of this fraction. The anti-inflammatory activity of FMEOH-1, FMEOH-F and FDCM fractions can be attributed to the considerable amounts of phenolic compounds, especially flavonoids, in these fractions. It was impossible to establish the DL50 in mice for EEB until the administration of the dose of 6 g / kg

Seasonality study of essential oil from leaves of Cymbopogon densiflorus and nanoemulsion development with antioxidant activity.

The development of formulations that maintain the biological and physical chemistry properties of essential oils is an important choice when they are used as an active ingredient. This study aimed to characterize the essential oil from leaves of Cymbopogon densiflorus and evaluate the antioxidant activity of the oil, and to produce a nanoemulsion formulation containing it. The essential oil was obtained by hydrodistillation, and seasonality was analysed every 2 months by gas chromatography?mass spectrometry, showing that more than 90% of the composition was maintained for the whole period and that the major compounds were trans?p?menta?2,8?dien?1?ol, cis?p?menta?2,8?dien?1?ol, trans?p?menta?1(7),8?dien?2?ol, cis?piperitol, and cis?p?menta?1(7),8?dien?2?ol. Stable nanoemulsions were prepared by phase inversion method encapsulating the essential oil. The antioxidant activity was evaluated by 2,2?diphenyl?1?picrylhydrazyl (DPPH) free radical scavenging and 2,2??azino?bis(3?ethylbenzothiazoline?6?sulphonic acid (ABTS) methods. In the first test, free and nanoemulsified essential oil showed half?maximal inhibitory concentration (IC50) values equivalent to 14.689 and 3.692 mg mL?1, respectively. In the second test, these values were 0.567 and 0.43 mg mL?1. The development of nanoemulsion?based essential oil from leaves of C. densiflorus was viable, and the formulated oil was able to reproduce the antioxidant activity at a concentration four times lower than that of the pure essential oil

Antiedematogenic and antinociceptive effects of leaves extracts from Protium spruceanum Benth.

Ethnopharmacological relevance: In traditional medicine, gums and oil-resins from Protium species have been used for many diseases, however, there are no reports of studies of Protium spruceanum? leaves. Materials and methods: The antiedematogenic and antinociceptive effects of crude ethanol extract (EEB) from leaves of P. spruceanum and its fractions were evaluated in biological models. The fractions were obtained with hexane (FHEX) and methanol (FMEOH). Rat paw edema induced by carrageenan, writhing test, formalin test, hot plate test and the toxicity of EEB were performed. Results: Phytochemical analysis has shown the presence of a and b-amyrins as major constituents of FHEX. Promising results of anti-inflammatory and antinociceptive activity were found for EEB, FHEX and FMEOH. Also were observed the EEB at 6000 mg/kg showed no toxicity. Conclusions: One might suggest that the activities of FHEX are due to the presence of a and b-amyrins and contributes to the biological activities of EEB

Bioprospecção das atividades antioxidante e antimicrobiana de espécies vegetais medicinais coletadas em Ouro Preto-MG.

O presente estudo foi realizado com os extratos etanólicos brutos de seis espécies vegetais (Bathysaaustralis, Piper corcovadensis, Siparuna brasiliensis, Picramnia sp., Piper richardiifolium, Eugenia cf. cerasiflora) de uso medicinal, coletadas na região de Ouro Preto-MG. Os extratos etanólicos foram avaliados frente à atividade antioxidante (método do DPPH) e antimicrobiana (Concentração Inibitória Mínima, CIM), bem como submetidos à dosagem de compostos fenólicos (reagente Folin-Ciocalteau) e flavonóides totais (Cloreto de Alumínio). Os resultados evidenciaram que o extrato de Siparuma brasiliensis apresentou maior atividade antioxidante (CE50 17,712 μg/mL) e o de Piper richardiifolium a melhor atividade antimicrobiana para Staphylococcus aureus (300 μg/mL) e Staphylococcus saprophyticus (200 μg/mL). Estes resultados sugerem que as atividades avaliadas estão diretamente relacionadas com a presença de compostos fenólicos, porém não necessariamente à presença de flavonoides.In the present study was used crude ethanolic extract from six species of medicinal plants (Bathysaaustralis, Piper corcovadensis, Siparuna brasiliensis, Picramnia sp., Piper richardiifolium, Eugenia cf. cerasiflora) collected in Ouro Preto-MG region. These extracts were evaluated by antioxidant (DPPH method) and antimicrobial (Minimal Inhibitory Concentration, MIC) activities, and submitted to phenolic compounds (Folin-Ciocalteau reagent) and total flavonoids (Aluminum chloride) contents. The results demonstrated that the extract of Siparuma brasiliensis showed the highest antioxidant activity (CE50 17,712 μg/mL) and Piper richardiifolium the best antimicrobial activity for S. aureus (300 μg/mL) e S. sprophyticus (200 μg/mL). These results suggest that the evaluated activities are directly related to the presence of phenolic compounds, but not necessarily to the presence of flavonoids

Protective Effect of Baccharis trimera Extract on Acute Hepatic Injury in a Model of Inflammation Induced by Acetaminophen

Background. Acetaminophen (APAP) is a commonly used analgesic and antipyretic. When administered in high doses, APAP is a clinical problem in the US and Europe, often resulting in severe liver injury and potentially acute liver failure. Studies have demonstrated that antioxidants and anti-inflammatory agents effectively protect against the acute hepatotoxicity induced by APAP overdose. Methods. The present study attempted to investigate the protective effect of B. trimera against APAP-induced hepatic damage in rats. The liver-function markers ALT and AST, biomarkers of oxidative stress, antioxidant parameters, and histopathological changes were examined. Results. The pretreatment with B. trimera attenuated serum activities of ALT and AST that were enhanced by administration of APAP. Furthermore, pretreatment with the extract decreases the activity of the enzyme SOD and increases the activity of catalase and the concentration of total glutathione. Histopathological analysis confirmed the alleviation of liver damage and reduced lesions caused by APAP. Conclusions. The hepatoprotective action of B. trimera extract may rely on its effect on reducing the oxidative stress caused by APAP-induced hepatic damage in a rat model. General Significance. These results make the extract of B. trimera a potential candidate drug capable of protecting the liver against damage caused by APAP overdose