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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Antiinflammatory, antiaggregant activity and central effects of alpha and beta amyrin from protium heptaphyllum Aubl March. / Atividade antiinflamÃtoria, antiagregante plaquetÃria e efeitos centrais de alfa e beta amirina isolada de protium heptaphyllum aubl march

Gislei Frota AragÃo 28 June 2004 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / The species Protium heptaphyllum Aubl. March. belonging to the family Burseraceae is common in several areas of Brazil, where is known as almecega or white pitch. The plant is used popularly an anti-inflammatory and antiulcer. The objective of the present work was to study the pharmacological effects of a isomeric mixture of two triterpenes: alpha and beta amyrin (AMI) isolated from Protium heptaphyllum. The pharmacological activities (antinociceptive, antiedematogenic, central and antiaggregant), of AMI were studied in mice, using several experimental models. AMI inhibited the abdominal contractions induced by acetic acid in 73 and 94% in the doses of 10 and 50 mg/Kg, i.p., respectively, when compared to control. In the formalin test, the effect was observed in the two phases, with inhibitions of 37 and 51 % (1st phase) and 60 and 73% (2nd phase) after the administration of 10 and 50 mg/Kg,i.p., respectively. In the hot plate test, AMI increased the latency to the thermal stimulus in the dose of 50 mg/Kg, i.p., with 62, 71 and 25% inhibitions after 30, 60 and 90 min, respectively). The antinociceptive effect is mainly peripheral and independent of the opioid system. In the models of paw edema induced by carrageenan and dextran in mice, AMI demonstrated a antiedematogenic dose-dependent effect, in the two models. The healing effect of AMI, when administered after the formation of the edema was also evaluated with the two edematogenic agents (carrageenan and dextran), AMI was more effective to treat the edema provoked by the carrageenan. The antiedematogenic effect of AMI was not potentiated in the presence of indometacin (cyclooxigenase inibitor), however the association with thalidomide, a strong inhibitor of the liberation of TNF-alfa, resulted in a synergistic effect and therefore larger than the effect of each one of the drugs separately, indicating that the mechanism of action involves inhibition of levels of TNF-alfa. The central effect of AMI (the decrease of the exploratory activity and the rearing frequency in the Open Field test) were also dose-dependently. In the elevated plus maze test it was observed an anxiolytic effect with AMI in the dose of 50 mg/Kg, i.p. The inhibition of platelet was observed in human platelets, where AMI inhibited the aggregation induced by following agonists: ADP (3mcM), collagen (10mcM) and arachidonic acid (150mcg/mL). This effect was potentiated by acetylsalicylic acid (a ciclooxigenase inhibitor), mainly by the ADP agonist. The results of the work allowed to conclude us that AMI have analgesic, anti-inflammatory (profilatic and terapeutic effects), sedative, anxiolytic activities as well as also an antiaggregation affect of human platelets. / A espÃcie Protium heptaphyllum Aubl. March. pertencente a famÃlia Burseraceae, à comum em vÃrias regiÃes do Brasil, onde à conhecida como almecega ou breu branco. à muito utilizada popularmente como antiinflamatÃria e antiÃlcera. O objetivo do presente trabalho foi estudar os efeitos farmacolÃgicos de uma mistura isomÃrica de dois triterpenos: a alfa e beta amirina (AMI) isolados do Protium heptaphyllum. Foram estudadas, em camundongos, as atividades antinociceptiva, antiedematogÃnica, antiplaquetÃrio e aÃÃes em nÃvel de Sistema Nervoso Central (SNC), utilizando vÃrios modelos experimentais. AMI inibiu as contorÃÃes abdominais induzidas por ac. acÃtico em 73 e 94% nas doses de 10 e 50 mg/Kg, i.p., respectivamente. No teste da formalina o efeito à observado nas duas fases, com inibiÃÃes de 37 e 51% na 1a fase e 60 e 73% na 2a fase depois da administraÃÃo de 10 e 50 mg/Kg,i.p., respectivamente. No teste da placa quente a AMI aumenta a latÃncia ao estÃmulo tÃrmico na dose de 50 mg/Kg, i.p. (62, 71 e 25% de inibiÃÃo nos tempos 30, 60 e 90 min, respectivamente), o efeito antinociceptivo à principalmente perifÃrico e independe do sistema opiÃide. Nos modelos de edema de pata induzido por carragenina e por dextrano em camundongos a AMI demonstrou efeito antiedematogÃnico, com efeito, dose-dependente, nos dois modelos. O efeito curativo onde a AMI foi administrada apÃs a formaÃÃo do edema foi avaliado tambÃm com os dois agentes edematogÃnicos citados e a AMI foi mais eficaz para tratar o edema provocado pela carragenina. O efeito antiedematogÃnico da AMI nÃo foi potencializado na presenÃa de indometacina (droga inibidora de ciclooxigenases), contudo a associaÃÃo com talidomida, que reconhecidamente inibe a liberaÃÃo de Fator de Necrose Tumoral alfa (TNFalfa), resultou em efeito sinÃrgico e, portanto maior do que o efeito de cada uma das drogas isoladamente, indicando que o mecanismo de aÃÃo envolve inibiÃÃes de nÃveis de TNFalfa. Efeitos ao nÃvel de Sistema Nervoso Central foram verificados pela AMI do tipo dose-dependente como a diminuiÃÃo da capacidade exploratÃria e a freqÃÃncia de rearing no teste do Campo Aberto e no teste do labirinto em cruz elevado observou-se um efeito ansiolÃtico com AMI na dose de 50 mg/Kg. O efeito antiagregante plaquetÃrio foi observado em plaquetas humanas, onde a AMI inibiu a agregaÃÃo frente, aos agonistas testados: ADP (3mcM), colÃgeno (10mcM) e Ãc. araquidÃnico (150mcg/mL). Este efeito foi potencializado pelo AAS (inibidor da ciclooxigenase), frente principalmente, ao agonista ADP (Adenosina Difosfato). Os resultados do trabalho nos permitiram concluir que a AMI possui atividades analgÃsicas, antiinflamatÃrias (tanto quando utilizado profilaticamente como tambÃm terapeuticamente), sedativas, ansiolÃtico e antiagregante plaquetÃria.
2

Isolation and characterization of compounds from Calodendrum capense (Rutaceae) and Lydenburgia cassinoides (Celastraceae) for treatment of fungal and bacterial infections in immunocompromised patients

Sakong, B.M. (Bellonah Motshene) 31 May 2013 (has links)
Infectious diseases are a serious concern worldwide especially in immune-compromised patients. Some of these diseases are considered to be contagious and are spread via airborne transmission, while others are not contagious, i.e. non-communicable diseases. The problem is compounded by the emergence of pathogens resistant to currently used antimicrobial drugs. A wide range of microbes including bacteria, fungi, parasites, viruses and protozoans are implicated as causative agents of various diseases. Many patients without ready access to Western medical facilities rely on medicinal plants for the cure of various ailments including infectious diseases. Two plant species used in South African traditional medicine for treating infectious diseases, namely Calodendrum capense Thunb. (Rutaceae) and Lydenburgia cassinoides N. Robson (syn. Catha transvaalensis, Celastraceae) were screened for antimicrobial activities against a range of fungi, bacteria and mycobacteria. The test organisms included Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Mycobacterium smegmatis and M. bovis BCG. The L. cassinoides acetone extract generally had good activity, with MIC values ranging from 0.04 to 0.15 mg/ml while the C. capense extract MIC values ranged from 0.31 to 0.62 mg/ml against the fungi. The hexane extract of L. cassinoides had good activity (MIC = 0.04 mg/ml) against M. smegmatis and the methanol extract had MIC = 0.16 mg/ml against M. bovis BCG. The two plant species had reasonable antibacterial activity against S. aureus and P. aeruginosa, with MIC values ranging from 0.16 to 0.32 mg/ml. Antibacterial activity against Escherichia coli and Enterococcus faecalis resulted in MIC = 0.63 mg/ml for both plants. However in the bioautography assay, the hexane extracts of C. capense and L. cassinoides had good activity against S. aureus, showing active zones of bacterial growth inhibition. The aim of this study was to isolate and characterize the active compounds, with emphasis on antifungal activity, from Calodendrum capense and Lydenburgia cassinoides that may be useful in treating opportunistic infections in immunocompromised patients. Bioassay-guided evaluation of the antimicrobial active components of both hexane fractions using C. neoformans and C. albicans as test organisms led to the isolation and characterization of lupeol from C. capense and ß-amyrin from L. cassinoides. The MIC values of lupeol and ß-amyrin ranged from 1.5 to 6.2 µg/ml against all the tested organisms. Both compounds were also tested against a resistant strain of Candida albicans which resulted in MICs of 3.2 and 6.2 µg/ml respectively. Crude extracts and compounds were also tested for cytotoxicity against human liver (C3A) cells. The crude plant extracts had a low cytotoxicity with average LC50 values of 205.8 ± 8.38 µg/ml for L. cassinoides and 83.07 ± 44.66 µg/ml for C. capense. LC50 values for the isolated compounds were greater than 200 µg/ml, the highest concentration tested. Selectivity index (SI) values were calculated using the formula SI = LC50/MIC. The SI values of the crude extracts of the two plant species ranged between 0.18 and 0.91, showing that these extracts were relatively toxic compared to the antimicrobial activity as the SI values were less than 1. However, the compounds ß-amyrin and lupeol had good activity and low toxicity with SI values greater than 10. In conclusion both plant species showed broad-based antimicrobial activity against the standard ATCC strains of bacterial and laboratory isolates of fungal pathogens. Purified compounds with very good antifungal activity and negligible detectable cytotoxicity, namely lupeol from C. capense and ß-amyrin from L. cassinoides (both pentacyclic triterpenoids) were isolated. This is apparently the first report of these two compounds from these two plant species. In our research group, lupeol has been isolated from various other plant species and it is known to have antimicrobial and anti-inflammatory activities. The second compound, ß-amyrin, reportedly has anti-inflammatory, antitumor, antibacterial, gastroprotective and hepatoprotective effects. The findings from this study show that the two isolated compounds were highly active against fungal and bacterial pathogens, with the lowest MIC value of 0.015 mg/ml. Both compounds showed much better selectivity index values with regard to antifungal activity compared to those of the crude extracts. The compounds also had good activity against the two Mycobacterium strains tested, indicating potential application in antimycobacterial therapy. The results may validate to an extent the use of these two plants as anti-infectious agents in traditional medicine. The compounds have potential for development into therapeutic agents, but various factors will need to be investigated further, including in vivo efficacy and safety, as well as other aspects such as mode of administration. / Dissertation (MSc)--University of Pretoria, 2012. / Paraclinical Sciences / unrestricted
3

Part I: Evaluation Of Russian Synthetic Compounds As A Potential Source Of New Drug Leads Agains Breast And Colon Cancer Part Ii: Isolation Of Beta-amyrin Formate From Eucalyptus Viminalis Labill And Investigation Of Its Colon Cancer Activity

Cohanoschi, Mihaela 01 January 2004 (has links)
Although modern medicine made great steps toward curing most diseases considered deadliest, yet cancer remains one of the major public health problems. The first part of this thesis investigates a new source of selective compounds that are potential candidates against cancer. Fifteen Russian compounds were tested in order to establish their efficiency against two types of cancer: human breast SK-Br-3 and colorectal carcinoma HT-29. The bioassay results show that seven of the new synthetic Russian compounds can be considered new drug leads, based upon their low toxicity and efficacy in slowing the growth of human breast cancer and colon cancer cells. The goal of the second part of the thesis was to isolate pure compounds that inhibit the growth of cancer cells from the methylene chloride extract of Eucalyptus viminalis Labill. This plant was selected for investigations since a preliminary screening of plants from Russia indicated that had activity against cancer. The result of this work was the isolation of a pure compound which has been analyzed using different spectroscopic techniques such as MS, HPLC, 1H-NMR, DEPT, 13C-NMR. The extracted compound was â-amyrin formate, which was previously reported by Malhotra,[49] from Canarium strictum Gum in 1987. Also, the bioassay results indicated that â-amyrin formate might be considered a possible drug lead against colon cancer and can be recommended for further investigations. This is the first report of isolation of â-amyrin formate from Eucalyptus viminalis Labill and the first test of the activity of this compound against colon cancer.
4

Obtenção de compostos bioativos de folhas de uvaia (Eugenia pyriformis Cambess.) utilizando CO2 supercrítico e extração com solvente assistida por ultrassom / Obtainment of bioactive compounds from uvaia (Eugenia pyriformis Cambess.) leaves using supercritical CO2 and ultrasound-assisted extraction

Klein, Elissandro Jair 04 February 2016 (has links)
Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2018-06-04T23:33:22Z No. of bitstreams: 1 Elissandro_Klein_2016.pdf: 4516260 bytes, checksum: 605fbf2e69fd746b1152b1431bf0dca5 (MD5) / Made available in DSpace on 2018-06-04T23:33:22Z (GMT). No. of bitstreams: 1 Elissandro_Klein_2016.pdf: 4516260 bytes, checksum: 605fbf2e69fd746b1152b1431bf0dca5 (MD5) Previous issue date: 2016-02-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Eugenia pyriformis Cambess. (Uvaia), typical of the Atlantic Forest belongs to the Myrtaceae family, the same family of cherry, jabuticaba and other plants, currently studied due to their antioxidant, antimicrobial and medicinal properties. The interest in bioactive compounds obtained from natural sources has led to an increase in researches aiming to find these compounds in plant extracts. The extractions using conventional methods generally have some drawbacks, and an interesting alternative has been the use of non-conventional extraction technologies, such as the supercritical fluid and the ultrasound-assisted extraction. This work aims to study unconventional methods of obtaining uvaia extracts in order to obtain extracts rich in bioactive compounds. Factors such as the influence of type of extraction (supercritical fluid and ultrasound) and the used conditions on the yield and composition were evaluated. The results were compared to those obtained using the extraction by maceration, a conventional extraction method. After drying and milling the uvaia leaves, the plant material was subjected to extraction with the supercritical CO2 solvent under different conditions of temperature (40, 50 and 60 °C) and pressure (100, 150 and 200 bar), with a fixed flow of 2.0 kg min-1. In the ultrasound-assisted extraction, the effects of temperature (40, 50 and 60 °C), power (150, 250 and 350 W) and ratio between the mass of leaves and the volume of solvent (1:10, 1:15 and 1:20) were evaluated. The extracts obtained were chemically characterized by GC-MS giving β-amyrin (53.72 % for SFE and 71.25 % for UAE) and α-amyrin (24.63 % for SFE and 22.69 % for UAE) as main compounds. In the supercritical extraction, the pressure and the interaction between pressure and temperature showed statistically significant effects on the yield, with the best result being achieved at 200 bar and 60 °C, reaching 1.69%. The data obtained from the supercritical fluid extraction were used to adjust the extraction curves simulated by using two empirical models available in the literature. The tested models adjusted well to the experimental data and the analysis of the estimated parameters allowed to define which model best describes the kinetics of each experimental condition. For the ultrasound-assisted extraction, the best yield result found in the determination of the kinetics was 1.81% in 40 minutes, although in the experimental design a 3 minute time extraction was used due to the better characteristics showed by the extracts at this time. The best result obtained in experimental design with ultrasound was 1.79% provided 30% power, 60 °C and mas/solvent ratio 1:20. Statistical analysis of the experimental design of the ultrasound-assisted extraction indicated significant effects from the variables temperature, mass/solvent ratio and the interaction between power and mass/solvent ratio. The best results for amyrin content by extract weight was found for supercritical extraction, with 97.43%. The ultrasound-assisted extraction showed the best amyrin amount per mass of leaves, 12.13 g of the mixture of isomers per kg of dry leaf. / Eugenia pyriformis Cambess. (Uvaia), típica da Mata Atlântica pertence à família Myrtaceae, mesma família da pitanga, jabuticaba e outras plantas, atualmente estudadas devido às suas propriedades antioxidantes, antimicrobianas e medicinais. O interesse por compostos bioativos obtidos de fontes naturais tem levado ao aumento no número de pesquisas que visam encontrar esses compostos em extratos de plantas. As extrações que utilizam os métodos convencionais geralmente apresentam inconvenientes, e uma alternativa interessante tem sido a utilização de tecnologias não convencionais de extração, como a extração utilizando fluidos supercríticos e a extração assistida por ultrassom. O presente trabalho tem como objetivo estudar métodos não convencionais de obtenção de extratos de uvaia visando obter-se extratos ricos em compostos bioativos. Foram avaliados fatores como influência do tipo de extração (fluido supercrítico e ultrassom) e das condições utilizadas no rendimento e na composição. Os resultados foram comparados com os obtidos utilizando a extração por maceração, um método convencional de extração. Após secagem e moagem das folhas de uvaia, o material vegetal foi submetido à extração com o solvente CO2 supercrítico sob diferentes condições de temperatura (40, 50 e 60 oC) e de pressão (100,150 e 200 bar), com vazão fixa de 2,0x10-3 kg min-1. Na extração assistida por ultrassom, foram avaliados os efeitos da temperatura (40, 50 e 60 oC), da potência (150, 250 e 350 W) e razão entre massa de folhas e volume de solvente (1:10, 1:15 e 1:20). Os extratos obtidos foram caracterizados quimicamente por CG-EM apresentando com principais compostos β-amirina (53,72 % para EFS e 71,25 % para EAU) e α-amirina (24,63 % para EFS e 22,69 % para EAU). Na extração supercrítica, a pressão e a interação entre pressão e temperatura apresentaram efeitos estatisticamente significativos em relação ao rendimento, sendo que o melhor resultado foi encontrado com 200 bar e 60 oC, obtendo-se 1,69 %. Os dados obtidos na extração com fluido supercrítico foram utilizados para ajustar as curvas de extração simuladas utilizando dois modelos empíricos disponíveis na literatura. Os modelos testados ajustaram-se de forma satisfatória aos dados experimentais e a análise dos parâmetros estimados permitiu definir qual dos modelos melhor se ajustou à cinética de cada condição experimental. Para a extração assistida por ultrassom o melhor resultado de rendimento encontrado na determinação da cinética foi 1,81 % com 40 minutos, porém no planejamento experimental foi utilizado um tempo de extração de 3 minutos pois com esse tempo os extratos apresentavam melhores características, sendo portanto o melhor resultado obtido igual a 1,79 % na condição de 30 % de potência, 60 oC e razão massa/solvente de 1:20. A análise estatística do planejamento experimental da extração assistida por ultrassom indicou efeitos significativos das variáveis temperatura, razão massa/solvente e a interação entre potência e razão massa/solvente. Os melhores resultados de teor de amirina por massa de extrato foi encontrada para a extração supercrítica, com 97,43 %. A extração assistida por ultrassom apresentou a melhor quantidade de amirina por massa de folha, 12,13 g da mistura de isômeros por kg de folha seca.
5

Estudo da atividade antinoceptiva de β-amirina, um triterpeno pentaciclÃco isolado de Protium heptaphyllum March. em modelos experimentais de dor. / Studies on the antinociceptive activity of β-amyrin, a pentacyclic triterpene isolated from Protium heptaphyllum March. (Burceraceae) in experimental models of pain.

Cinthya Iamille Frithz BrandÃo de Oliveira 14 April 2010 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Amazonas / Os efeitos dos triterpenos pentaciclicos -amirina e -amirina, isolados a partir da resina de Protium heptaphyllum March. (Burseraceae), foram testados preliminarmente em modelos de nocicepÃÃo oral, sendo que -amirina apresentou significantes efeitos antinociceptivos, norteando a pesquisa com este isolado na investigaÃÃo de seus efeitos em modelos de dor orofacial induzida por capsaicina ou formalina e na dor induzida por capsaicina na cÃrnea de camundongos; na dor tÃrmica (testes de imersÃo de cauda em Ãgua quente e placa quente); e na nocicepÃÃo visceral induzida por Ãcido acÃtico 0,6%. Camundongos Swiss machos (n = 8 / grupo) foram prÃ-tratados com β-amirina (10, 30 e 100 mg / kg, v.o.), morfina (5 mg / kg, s.c.) ou controle (Ãgua destilada + 0,05% de Tween 80, v.o.), uma hora antes de capsaicina (20 L, 1,5 g) ou formalina (20L/animal) serem administradas na vibrissa direita. β-amirina tambÃm foi avaliada em teste comportamental relacionado à dor, desta vez por aplicaÃÃo tÃpica de capsaicina na conjuntiva do camundongo (âeye wiping testâ). Neste teste foi medido o tempo, em segundos, que o animal passou âlimpandoâ o olho durante um perÃodo de 10 minutos. O triterpenÃide demonstrou principalmente um efeito antinociceptivo dose-independente em todos os modelos de nocicepÃÃo testados. Na dor orofacial induzida por capsaicina, -amirina (30 e 100 mg/kg) e morfina foram mais eficazes na reduÃÃo da resposta nociceptiva. Nestas doses, as reduÃÃes foram de 81 e 90% para -amirina e 97% para morfina, respectivamente. No modelo de dor orofacial, a nocicepÃÃo produzida pela capsaicina à acompanhada por um aumento na resposta tÃrmica localizada (que foi mensurada por termometria), e reduzida significantemente pelo prÃ-tratamento dos animais com -amirina ou L-NAME, um inibidor da NOS. Em animais diabÃticos, a capsaicina injetada na vibrissa promoveu um menor grau de nocicepÃÃo orofacial comparada com os nÃo-diabÃticos. No teste da formalina, morfina e β-amirina apresentaram antinocicepÃÃo significativa reversÃvel nas duas fases por naloxona. No entanto, β-amirina (30 mg/kg) inibiu a segunda fase com maior eficiÃncia. Os valores de DE50 para β-amirina e morfina foram 16,44 mg/kg (LC 10,0-38,41) e 3 mg/kg (LC 2,5-5,0) na primeira fase e 43,37 mg/kg (LC 30,52-39,30) e 3 mg/kg (LC 2,5-5,0) na segunda fase, respectivamente. A co-administraÃÃo de β-amirina e morfina, em seus respectivos nÃveis de dose de DE50, nÃo apresentou qualquer efeito aditivo ou potencializador antinociceptivo. No entanto, as combinaÃÃes das doses DE25 e DE12,5 apresentaram uma antinocicepÃÃo comparÃvel ao efeito combinado da DE50, sugerindo que atravÃs da utilizaÃÃo de β-amirina, a dose analgÃsica de morfina poderia ser minimizada para evitar a sua alta dose e os efeitos colaterais associados. β-amirina tambÃm foi eficaz em aumentar o limiar de dor tÃrmica no teste da imersÃo da cauda (mais nÃo no teste placa quente) e, na reduÃÃo das contorÃÃes induzidas por Ãcido acÃtico. A antinocicepÃÃo produzida por β-amirina, foi significativamente bloqueada em animais prÃ-tratados com os respectivos antagonistas vermelho de rutÃnio (2 mg/kg, s.c.) e naloxona (1 mg/kg, i.p.), indicando o envolvimento de receptores da capsaicina (TRPV1) e opiÃides em seu mecanismo. No teste da formalina, de forma similar à morfina, β-amirina bloqueou significativamente a inibiÃÃo da ingestÃo alimentar associada a dor. Assim como morfina, β-amirina apresentou aÃÃo inibitÃria sobre o trÃnsito intestinal, efeito esse revertido pelo prÃ-tratamento com antagonista opiÃide nÃo seletivo, naloxona. Estes dados sugerem que β-amirina apresenta um potencial antinociceptivo comparÃvel à analgesia perifÃrica produzida pela morfina, evidencia a exploraÃÃo desta para o desenvolvimento de um analgÃsico nÃo-opiÃide Ãtil na farmacoterapia de patologias do trigÃmeo e visceral. / The effects of pentacyclic triterpene β-amiryn and β-amyrin, isolated from resin of Protium heptaphyllum March. (Burseraceae), were preliminarily showed significant tested in models of nociception oral, and antinociceptives effects, guiding the search with this isolate in the investigation of their effects in models of orofacial pain induced by capsaicin or formalin and against capsaicin-induced corneal pain; thermal pain (tail immersion test in hot water and hot-plate) and in acetic acid 0,6%-induced visceral nociception in mice. Male Swiss mice (n = 8 per group) were pre-treated with β-Amyrin (10, 30, and 100 mg/kg, p.o.), morphine (5 mg/kg, s.c.) or vehicle (distlled water + 0,05% Tween 80), one hour before the capsaicin (20 μl, 1.5 μg) or formalin (20 μl, 1.5%) injection into the right vibrissa. β-Amyrin was also assessed on pain-related behavioral test (Eye-wiping) by topical application of capsaicin (20 μl, 1.5 μg) on to the mouse conjuctiva and the time (sec) that the animal spent in eye wiping was determined during a 10 min period. The triterpenoid demonstrated mostly a dose-unrelated antinociception in all the test models of nociception. Against the orofacial pain induced by capsaicin, β-Amyrin (30 e 100 mg/kg, p.o.) and morphine showed greater potency in reducing the nociceptive response. At the doses employed, the reductions were 81 and 90% to β-Amyrin and 97% for the morphine, respectively. Capsaicin nociception in orofacial test is accompanied by a localized thermal flare (measured by thermometry), which was significantly diminished by pretreatment of animals with β-Amyrin or L-NAME, an NOS inhibitor. In four weeks diabetic mice, capsaicin injected into vibrissa pad demonstrated a lesser degree of orofacial nociception compared to non-diabetics. In formalin test, both morphine and β-Amyrin showed significant naloxone reversible antinociception in both phases. However, β-Amyrin inhibited the second phase response, more prominently, at 30 mg/kg. The caliculated ED50 values for β-Amyrin and morphine were 16,44 mg/kg (CL 10,0 - 38,41) and 3 mg/kg (CL 2,5 - 5,0) in the first phase and 43,37 mg/kg (CL 30,52 - 39,30) and 3 mg/kg (CL 2,5 - 5,0) in the second phase, respectively. Co-administration of β-Amyrin and morphine at their respective ED50 dose levels failed to demonstrate any additive or potentiating effect on anti-nociception. However, at ED25 and ED12.5 dose-combinations exhibited an antinociception that equalled their ED50 combination effect, suggesting that by the use of β-Amyrin, the analgesic dose of morphine could be minimised to avoid its high-dose-associated side-effects. Similar to morphine, β-Amyrin significantly blocked the pain-related suppression of food intake in formalin test. β-Amyrin (30 and 100 mg/kg was also effective in increasing the thermal pain threshold in hot-water tail immersion test (but not in hot-plate test), and in reducing the acetic acid-induced writhes. The antinociception produced by 30 mg/kg β-Amyrin was significantly blocked in animals pre-treated with the respective antagonists capsazepine (5 mg/kg, s.c.), and naloxone (1 mg kg/kg, i.p.), indicating the involvement of capsaicin (TRPV1) and opioid receptors in its mechanism. Like morphine, β-Amyrin showed an inhibitory effect on intestinal transit, an effect reversed by pretreatment with nonseletive opiÃide antagonist, naloxona. These data indicate that β-Amyrin has the antinociceptive potential comparable to peripheral analgesia produced by morphine that could be explored further on its suitability in developing a non-opioid analgesic useful in pharmacotherapy of trigeminal and visceral pathologies.
6

Estudo do potencial citotÃxico de novos Ãsteres sintÃticos derivados da mistura triterpenoidica α-/β-amirina em modelos experimentais in vitro. / Study of cytotoxic potential of new synthetic esters derivatives of the triterpenoid mixture α-/β-amirina in experimental models in vitro.

Assuero Silva Meira 31 January 2011 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / TriterpenÃides sÃo compostos que nos Ãltimos anos tÃm despertados grande interesse em razÃo de sua diversidade estrutural e da descoberta de um amplo espectro de atividades farmacolÃgicas. O presente estudo avaliou o potencial citotÃxico de quatro derivados de uma mistura de α-,β-amirina em linhagens tumorais humanas. Dentre estes, apenas o composto 3-O-Carboximaleinato de α-, β-amirina (3a/3b) foi ativo, especialmente na linhagem leucÃmica HL-60, com valores de IC50 variando entre 1,8 e 3,0 ÂM. Este derivado foi avaliado, tambÃm frente à outra linhagem leucÃmica, K562, com IC50 variando entre 1,76 e 2,96 ÂM, sugerindo uma especificidade desta substÃncia para leucemias. E sua especificidade para cÃlulas tumorais foi confirmada em ensaios de citotoxicidade em cÃlulas nÃo transformadas, sendo testada em uma linhagem de macrÃfagos, J774 (IC50 entre 3,10 e 3,60 ÂM) e em cÃlulas mononucleares do sangue perifÃrico humano (CMSPH), cuja proliferaÃÃo nÃo foi impedida e nÃo houve dano ao DNA destas cÃlulas. Nenhum dos compostos mostrou atividade hemolÃtica contra eritrÃcitos de camundongos (EC50 > 200 Âg/mL), o que sugere uma citotoxicidade por mecanismos de aÃÃo mais especÃficos. Desta forma, a fim de determinar o mecanismo de aÃÃo envolvido, uma sequÃncia de experimentos in vitro foram realizados na linhagem HL-60. As cÃlulas foram tratadas em diferentes concentraÃÃes da amostra 3a/3b (1,5, 3,0 e 6,0 ÂM) por 24h. A viabilidade das cÃlulas HL-60 (teste azul de tripan e citometria de fluxo) foi reduzida nas concentraÃÃes de 3,0 e 6,0 ÂM, apÃs o tratamento. A anÃlise morfolÃgica das alteraÃÃes celulares realizada por mÃtodos de coloraÃÃo (May-GrÃnwald-Giemsa e laranja de acridina/brometo de etÃdio (LA/BE)) e por citometria de fluxo (integridade de membrana) revelaram caracterÃsticas tÃpicas de cÃlulas apoptÃticas (membrana Ãntegra, reduÃÃo do volume celular, nÃcleo picnÃtico e cromatÃlise), tambÃm nas concentraÃÃes de 3,0 e 6,0 ÂM. Outros testes por citometria de fluxo revelaram que houve externalizaÃÃo da fosfatidilserina, que nÃo houve formaÃÃo de espÃcies reativas de oxigÃnio (EROS) e que a molÃcula 3a/3b induziu apenas a via extrÃnseca da apoptose, pela ativaÃÃo da caspase iniciadora 8 e a consequente ativaÃÃo das caspases efetoras 3 e 7. Estes dados indicam um mecanismo citotÃxico por induÃÃo de uma via apoptÃtica, envolvendo receptores de morte. Por conseguinte, estes resultados apontam o potencial citotÃxico do anÃlogo 3a/3b. / Triterpenoids are compounds that in recent years have aroused considerable interest because of their structural diversity and the discovery of a broad spectrum of pharmacological activities. This study evaluated the cytotoxic potential of four derivatives of a mixture of α-, β-amyrin in human tumor cell lines. Among these, only compound 3-O-α-Carboximaleinato of, β-amyrin (3a/3b) was active, especially in the leukemic cell line HL-60, with IC50 values ranging from 1.8 to 3.0 ÂM. This derivative had its cytotoxic evaluated, also at the other leukemia cell line, K562, with IC50 values ranging between 1.76 and 2.96 ÂM, suggesting a specificity of this substance for leukemia. And their specificity for tumor cells was confirmed in cytotoxicity assays in a strain of macrophages, J774 (IC50 between 3.10 and 3.60 ÂM) and mononuclear cells in human peripheral blood mononuclear cells, whose proliferation was not prevented, and there wasnât damage in the DNA of these cells. None of the compounds showed hemolytic activity against erythrocytes of mice (EC50> 200 mg / mL), suggesting a cytotoxic mechanism more specific. Thus, to determine the mechanism of action involved, sequences of in vitro experiments were performed in HL-60 cell line. Cells were treated at different concentrations of the sample 3a/3b (1.5, 3.0 and 6.0 ÂM) during 24h. The viability of HL-60 cells (trypan blue test and flow cytometry) was reduced at concentrations of 3.0 and 6.0 ÂM after treatment. Morphological analysis of cellular changes performed by staining methods (May-GrÃnwald-Giemsa and acridine orange / ethidium bromide (LA / BE)) and by flow cytometry (membrane integrity) showed typical features of apoptotic cells (intact membrane , reduction of cell volume, picnotic nucleus and chromatolysis), also at concentrations of 3.0 and 6.0 ÂM. Further testing by flow cytometry revealed that there was externalization of phosphatidylserine, there was no formation of reactive oxygen species (ROS) and that the molecule 3a/3b only induced the extrinsic pathway of apoptosis by activation of initiator caspase 8 and subsequent activation of caspases 3 and 7. These data indicate a cytotoxic mechanism induced by an apoptotic pathway, involving death receptors. Therefore, these results indicate the cytotoxic potential of 3a/3b analogue.
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Evaluation of hypoglycemic and hypolipidemic activity of mixture of α,β-amyrin, pentacyclic triterpenes isolated of protium heptaphyllum in mice / AvaliaÃÃo das atividades hipoglicemiante e hipolipidÃmica da mistura de α,β-amirina, triterpenos pentacÃclicos isolados do Protium heptaphyllum, em camundongos

Julyanne Torres Frota 10 November 2011 (has links)
nÃo hà / The Protium heptaphyllum (almecegueira) exudes an amorphous resin consisting of four binary mixtures of triterpenoids, and the mixture of ,-amyrin its major constituent. In folk medicine, the resin of Protium heptaphyllum is used as anti-inflammatory, gastroprotective, analgesic, expectorant and healing. The mixture of pentacyclic triterpenes ,-amyrin (AB) (63:37) has gastroprotective, antipruritic, antiinflammatory and antioxidant properties. Experimental studies with pentacyclic triterpene compounds belonging to the groups ursan, oleanan and lupan showed inhibition of different enzyme systems intimately related to metabolism/absorption of carbohydrates and lipids. Thus the hypoglycemic and hypolipidemic activity of AB was evaluated in Swiss mice, the models of diabetes induced by streptozotocin (STZ) and alloxan (ALX) and hyperlipidemia induced by triton WR-1339 and hyperlipidemic diet (DH). AB (10, 30 and 100mg/kg) was able to reduce blood glucose in a model of acute treatment in STZ-induced diabetes, we observed two times (3 and 5 hours after administration of AB). In five days after treatment of diabetic animals by ALX, AB (30 and 100 mg/kg) also decreased hyperglycemia, an effect also observed for the use of glibenclamide (10 mg/Kg) in both models. But in normal animals, AB did not affect blood glucose, unlike the positive control glibenclamide (10 mg/kg). Although the model of diabetes for ALX, AB reduced total cholesterol (TC) serum at a dose of 100mg/kg, and triglycerides (TG) at doses of 30 and 100 mg/kg. In this same model, reduced the serum amylase AB (AB 30 and 100 mg/kg) and serum lipase (AB 100 mg/kg), a result also observed in normal animals, the same doses. In the Oral Glucose Tolerance Test (OGTT), AB (30 and 100 mg/kg) was shown to reduce blood glucose levels 60 min after administration of glucose, and AB (10, 30 and 100 mg/kg) in 90 min. In the model of hyperlipidemia by triton, AB (10, 30 and 100 mg/kg) significantly reduced the levels of TC and TG, in times of 24 and 48 h after administration of triton, an effect also observed for fenofibrate (200 mg/kg) used as positive control. The levels of HDL-c elevation experienced with the use of AB at all doses and times observed, as well as fenofibrate. In the model of hyperlipidemia by HD, AB (10, 30 and 100 mg/kg) controlled weight gain of animals receiving HD, as well as reduced TC, TG, LDL-c and VLDL-c, although the latter only in doses 30 and 100 mg/kg. These two doses were also effective in raising HDL-c. All doses of AB administered reduced the atherogenic index. All doses of AB also reduced the hepatic cholesterol in this model. All effects reported were similar to the positive control (fenofibrate 200 mg/kg). AB (10, 30 and 100 mg/kg) was able to significantly improve the antioxidant defenses of the liver, because it elevated the activity of hepatic SOD and CAT when compared to control high-fat diet, and raised the level of NP-SH in dose of 100 mg/kg, as well as reduced lipid peroxidation by decreasing the MDA, at all doses. Together, these results indicate that α,β-amyrin has hypolipidemic and hypoglycemic effect and deserves further evaluation in larger animal models that simulate chronic conditions of diabetes and dyslipidemia, in addition to research on their mechanism of action. / O Protium heptaphyllum (almecegueira) exsuda uma resina amorfa constituÃda de quatro misturas binÃrias de triterpenÃides, sendo a mistura de ,-amirina o constituinte majoritÃrio. Na medicina popular, a resina de Protium heptaphyllum à utilizada como antiinflamatÃria, gastroprotetora, analgÃsica, expectorante e cicatrizante. A mistura de triterpenos pentacÃclicos ,-amirina (AB) (63:37) possui propriedades gastroprotetora, antipruriginosa, antiinflamatÃria e antioxidante. Estudos experimentais com compostos triterpÃnicos pentacÃclicos que pertencem ao grupo ursano, oleanano e lupano mostraram a inibiÃÃo de diferentes sistemas enzimÃticos intimamente relacionados ao metabolismo/absorÃÃo de carboidratos e lipÃdios, deste modo, a atividade hipoglicemiante e hipolipemiante de AB foi avaliada, em camundongos Swiss, nos modelo de diabetes induzida por estreptozotocina (STZ) e por aloxano (ALX) e hiperlipidemia induzida por triton WR-1339 e dieta hiperlipidÃmica (DH). AB (10, 30 e 100mg/Kg) foi capaz de reduzir a glicemia num tratamento agudo no modelo de diabetes induzida por STZ, nos dois tempos observados (3 e 5h apÃs administraÃÃo de AB). Em tratamento apÃs cinco dias de animais diabÃticos por ALX, AB (30 e 100mg/Kg) tambÃm diminuiu a hiperglicemia, efeito este, tambÃm observado para o uso de glibenclamida (10mg/Kg) nos dois modelos. PorÃm em animais normais, AB nÃo alterou a glicose sanguÃnea, ao contrÃrio do controle positivo glibenclamida (10 mg/Kg). Ainda no modelo de diabetes por ALX, AB reduziu o colesterol total (CT) sÃrico na dose de 100mg/Kg, bem como os triglicerÃdeos (TG) nas doses de 30 e 100 mg/Kg. Neste mesmo modelo, AB reduziu a amilase sÃrica (AB 30 e 100 mg/Kg) e a lipase sÃrica (AB 100mg/Kg), resultado este observado tambÃm em animais normais, nas mesmas doses. No Teste Oral de TolerÃncia à Glicose (TOTG), AB (30 e 100 mg/Kg) mostrou reduzir a glicemia 60 min apÃs a administraÃÃo de glicose, bem como AB (10, 30 e 100 mg/Kg) em 90 min. No modelo de hiperlipidemia por triton WR-1339, AB (10, 30 e 100mg/Kg) reduziu de forma significativa os nÃveis de CT e TG, nos tempos de 24h e 48h apÃs a administraÃÃo do triton WR-1339, efeito observado tambÃm para fenofibrato (200mg/Kg) utilizado como controle positivo. Os nÃveis de HDL-c sofreram elevaÃÃo com o uso de AB em todas as doses e tempos observados, assim como o fenofibrato. No modelo de hiperlipidemia por DH, AB (10, 30 e 100mg/Kg) controlou o ganho de peso dos animais que receberam a DH, bem como reduziram CT, TG, LDL-c e VLDL-c, porÃm este Ãltimo somente nas doses de 30 e 100mg/Kg. Estas duas doses tambÃm foram eficazes para elevar o HDL-c. Todas as doses de AB administradas reduziram o Ãndice aterogÃnico. Todas as doses de AB tambÃm reduziram o colesterol hepÃtico neste modelo. Todos os efeitos relatados foram similares ao controle positivo (fenofibrato 200mg/Kg). AB (10, 30 e 100 mg/Kg) foi capaz de melhorar significativamente as defesas antioxidantes do tecido hepÃtico, pois elevou a atividade das enzimas catalase e superÃxido dismutase hepÃticas, quando comparado ao controle dieta hiperlipÃdica, bem como elevou o nÃvel dos grupos sulfidrÃlicos nÃo protÃicos na dose de 100mg/Kg, assim como reduziu a peroxidaÃÃo lipÃdica ao diminuir o malondialdeÃdo, em todas as doses. Em conjunto, esses resultados indicam que α,β-amirina possui efeito hipoglicemiante e hipolipemiante e que merece maior avaliaÃÃo futura em modelos animais que simulem situaÃÃes crÃnicas de diabetes e dislipidemias, alÃm de pesquisa de seu mecanismo de aÃÃo.
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METABÓLITOS SECUNDÁRIOS EM VERNONIA TWEEDIEANA BAKER / SECUNDARY METABOLIC OF VERNONIA TWEEDIEANA BAKER

Zanon, Ricardo Basso 07 April 2006 (has links)
The species Vernonia tweedieana Baker is an herbaceous plant widely distributed in the plains of Paraguai, Argentina and south of Brazil and popularly known as assa-peixe . This plant is used in traditional medicine as an expectorant medicament. So far, this plant was not studied on the phytochemical and biological point of view. This work is a contribution to the phytochemical study of the Asteraceae. The leaves of V. tweedieana Baker were collected in march of 2004, in Ijuí Rio Grande do Sul, Brazil, and identified by Dr. Geraldo C. Coelho (UNIJUÍ). The respective voucher specimen was deposited in the herbarium of the Federal University of Santa Maria (UFSM)-RS (code SMDB 9536). The leaves (1.900 g) were dried in an air circulating stove at 40 ºC, pulverized in mill and extracted by maceration with 65% EtOH at room temperature for seven days. The ethanolic extract was filtered and the ethanol was removed. Finally, the extract was retake in water and partitioned using organics solvents with increased polarity: CH2Cl2, AcOEt and n-BuOH. We report the isolation and identification of six constituents of the CH2Cl2 fraction: the triterpenes a-amyrin, b-amyrin and lupeol and the steroids b- sitosterol, stigmasterol and spinasterol. The flavanone eriodictyoI was isolated from the AcOEt fraction. The constituents were identified through spectral data of the infra-red, GC-MS, 1H-NMR, 13C-NMR and DEPT. No deaths and other signs of toxicity and adverse effect were observed in the evaluation of acute toxicity with doses up to 5.000 mg/kg, that is the maximum dose for acute oral toxicity test for extract of plants. Also, through DPPH method, AcOEt and n-BuOH fractions of the plant showed good antioxidant activity with IC50 22.52 and 17.44 mg/mL, respectively. / O uso de plantas medicinais sempre teve uma importância vital no cotidiano da humanidade. No entanto, apenas uma pequena parte destas já foram estudadas e tiveram suas ações farmacológicas comprovadas cientificamente. Um exemplo de planta ainda desconhecida quimicamente é Vernonia tweedieana Baker (Asteraceae), vulgarmente conhecida como assa-peixe. É uma planta característica da região Sul do Brasil que é usada popularmente para o tratamento de doenças respiratórias, principalmente pelas suas propriedades expectorantes. Este trabalho descreve o isolamento e identificação de seis constituintes químicos presentes no extrato CH2Cl2 e de um no extrato AcOEt das folhas de Vernonia Tweedieana Baker. As folhas foram coletadas em março de 2004, no município de Ijuí RS. A espécie foi localizada e identificada pelo Prof. Dr. Geraldo C. Coelho (DeBQ-UNIJUÍ). Material testemunha encontra-se depositado no Herbário do Departamento de Biologia da UFSM sob o registro n° SMDB 9536. O material vegetal seco e moído (1.900 g) foi macerado utilizando como solvente etanol:água (65:35, v/v). Após sete dias o extrato foi filtrado e concentrado sob pressão reduzida para remover o etanol. Fez-se fracionamento desse extrato bruto com solventes orgânicos de polaridades crescentes (CH2Cl2, AcOEt, n- BuOH). Da fração CH2Cl2 caracterizou-se os triterpenos a e b-amirinas e lupeol, ainda os esteróides b-sitosterol, estigmasterol e espinasterol; e da fração AcOEt o flavonóide eriodictiol. Os compostos isolados foram analisados por CG-EM-IE, IV, RMN de 1H e RMN de 13C e seus dados espectroscópicos foram comparados com os obtidos da literatura. Ainda, na avaliação da toxicidade aguda foi verificado que nenhum dos extratos apresentou toxicidade em doses até 5.000 mg/mL. Também, pelo método do DPPH, foi constatada atividade antioxidante para as frações AcOEt e n-BuOH da planta, apresentando IC50 de 22,52 e 17, 44 mg/mL, respectivamente.
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Estudo do efeito farmacolÃgico da alfa, beta-amirina, uma mistura de triterpenos isolada de Protium heptaphyllum, na pancreatite aguda experimental / Pharmacological study of the effect of alfa,β-amyrin, a mixture of triterpenes isolated from Protium hepthaphyllum in acute pancreatitis experimental

Caroline MourÃo Melo 23 November 2009 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Os triterpenos pentacÃclicos sÃo compostos naturais com atividade antiinflamatÃria e citoprotetora e sÃo relativamente atÃxicos. A pancreatite aguda, uma inflamaÃÃo aguda do pÃncreas, pode levar à sÃndrome da resposta inflamatÃria sistÃmica (SRIS) e à sÃndrome da disfunÃÃo mÃltipla de ÃrgÃos (MODS), condiÃÃes que podem levar o paciente ao Ãbito. Neste trabalho, a mistura de triterpenos pentacÃclicos alfa,β-amirina, isolada do Protium hepthaphyllum, foi investigada quanto aos seus efeitos nos modelos de pancreatite aguda induzida por L-arginina em ratos e por ceruleÃna em camundongos. No modelo de pancreatite aguda induzida por L-arginina, ratos Wistar machos foram tratados com a mistura de alfa,β-amirina (10, 30 e 100 mg/kg, v.o.) ou com o veÃculo (2% de Tween 80 em Ãgua destilada, 10ml/kg) 48, 24 e 1,5h antes da administraÃÃo de L-arginina (2 x 2,5 g/kg; 1 h de intervalo) ou com metilprednisolona (30 mg/kg, i.m.) 30 min antes da administraÃÃo de L-arginina. Na pancreatite induzida por ceruleÃna, camundongos Swiss machos foram tratados com a mistura de alfa,β-amirina (10, 30 e 100 mg/kg, v.o.) ou com o veÃculo (2% de Tween 80 em Ãgua destilada, 10ml/kg) 48, 24 e 1,5h antes da administraÃÃo de ceruleÃna (5 x 50 μg/kg; 1 h de intervalo) ou com talidomida (200 mg/kg, v.o.) 1h antes da administraÃÃo de ceruleÃna. Animais tratados apenas com salina (0,9%, NaCl) foram incluÃdos nos dois modelos. Foram analisados o edema pancreÃtico, nÃveis sÃricos de amilase, lipase e citocinas (TNF alfa, IL-6), mieloperoxidase, substÃncias reativas ao Ãcido tiobarbitÃrico (TBARS), histologia e imunohistoquÃmica (TNF-alfa, iNOS e nitrotirosina) pancreÃtica. L-arginina e ceruleÃna aumentaram significativamente o edema pancreÃtico e os nÃveis sÃricos de amilase, lipase, TNF alfa, IL-6. A avaliaÃÃo histopatolÃgica do pÃncreas revelou a presenÃa de edema, infiltraÃÃo neutrofÃlica, hemorragia, vacuolizaÃÃo e necrose acinar. Foi observado um aumento acentuado na expressÃo de TNF alfa, iNOS e nitrotirosina na avaliaÃÃo por imunohistoquÃmica. O prÃ-tratamento com alfa e beta-amirina (10, 30 e 100 mg/kg, v.o.), metilprednisolona (30 mg/kg, i.m.) ou talidomida (200 mg/kg, v.o.) atenuaram significativamente a severidade da pancreatite aguda induzida tanto por L-arginina, quanto por ceruleÃna, evidenciado pela reduÃÃo do edema pancreÃtico, amilase, lipase e citocinas sÃricas, mieloperoxidase e TBARS pancreÃtico. AlÃm disso, o tratamento com alfa,β-amirina e com as drogas de referÃncia suprimiram as alteraÃÃes histopatolÃgicas e a expressÃo de citocinas e nitrotirosina pancreÃticas. Em conjunto, esses resultados indicam que alfa,β-amirina melhora a severidade da pancreatite aguda induzida por L-arginina ou ceruleÃna por agir como antiinflamatÃrio e antioxidante. / Triterpenes are natural compounds with anti-inflammatory and cytoprotective effects relatively non-toxic. Acute pancreatitis, an inflammation of the pancreas, may lead to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS), conditions that can lead the patient to death. In this study, a mixture of triterpenes isolated from Protium hepthaphyllum was investigated for their effects in models of acute pancreatitis. In the model of acute pancreatitis induced by L-arginine, male Wistar rats were treated with a mixture of ,β-amyrin (10, 30 and 100 mg/kg, p.o.) or with vehicle (2% Tween 80 in distilled water, 10 ml/kg) 48, 24 and 1.5 h before the administration of L-arginine (2 x 2.5 g/kg, 1 h apart) or with metilprednisolone (30 mg/kg, i.m.) 30 min before the administration of L-arginine. In cerulein-induced pancreatitis, male Swiss mice were treated with a mixture of ,β-amyrin (10, 30 and 100 mg/kg, p.o.) or with vehicle (2% Tween 80 in distilled water, 10 ml/kg) 48, 24 and 1.5 h before administration of cerulein (5 x 50 mg/kg, 1 h apart) or with thalidomide (200 mg/kg, p.o.) 1h before administration of cerulein. Animals treated with saline (0.9% NaCl) were included in both models. We analyzed the pancreatic edema, serum amylase, lipase and cytokines (TNF-, IL-6), myeloperoxidase, reactive substances to thiobarbituric acid (TBARS), histology and immunohistochemistry (TNF-, iNOS and nitrotyrosine) pancreatic. L-arginine and cerulein significantly increased pancreatic edema and serum levels of amylase, lipase, TNF- and IL-6. Histopathologic evaluation of pancreas revealed the presence of edema, neutrophil infiltration, hemorrhage, acinar vacuolization and necrosis. We observed a marked increase in the expression of TNF-, iNOS and nitrotyrosine in the evaluation by immunohistochemistry. The pre-treatment with alpha and beta-amyrin (10, 30 and 100 mg/kg, p.o.), metilprednisolone (30 mg/kg, i.m.) or thalidomide (200 mg/kg, p.o.) significantly attenuated the severity of acute pancreatitis induced by either L-arginine, and by cerulein, as evidenced by the reduction of pancreatic edema, amylase, lipase and serum cytokines, myeloperoxidase and pancreatic TBARS. Furthermore, treatment with ,β-amyrin and the reference drugs suppressed the histopathological changes and expression of cytokines and nitrotyrosine pancreatic. Together, these results indicate that the mixture of ,-amyrin reduces the severity of acute pancreatitis induced by L-arginine or cerulein acting as anti-inflammatory and antioxidant agent.
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AvaliaÃÃo do efeito antiflamatÃrio e antinociceptivo do α- e Ã-amirina, em modelo de doenÃa periodontal e nocicepÃÃo orofacial em ratos / EVALUATION OF THE ANTINOCICEPTIVE AND ANTI-INFLAMMATORY EFFECT OF α- e Ã-AMIRINA IN A MODEL OF DISEASE PERIODONTAL AND NOCICEPCION OROFACIAL IN RATS.

Sergio AraÃjo Holanda Pinto 24 September 2008 (has links)
nÃo hà / Este estudo avaliou o potencial antiinflamatÃrio do triterpeno &#945;, &#946;-amirina sobre a periodontite nas fases aguda e crÃnica, em ratos. A periodontite foi induzida pela colocaÃÃo de ligadura ao redor do 2 molar superior esquerdo. Ratos (n=8) foram prÃ-tratados com &#945;, &#946;-amirina (5 e 10 mg/kg,v.o). Falso-operados e controles positivos (lumiracoxibe, 20 mg/kg,v.o.e dexametasona, 1 mg/kg, i.p.) foram incluÃdos. Na fase aguda, os nÃveis do fator de necrose tumoral (TNF)-alfa no plasma foram medidos e o tecido gengival foi analisado para mieloperoxidase (MPO) e substÃncias tiobarbitÃricas Ãcido-reativas (TBARS). Tanto &#945;, &#946;-amirina, como dexametasona, diminuiu os nÃveis de TNF-alfa, MPO e TBARS. Jà na fase crÃnica, apÃs a induÃÃo da doenÃa, os animais foram acompanhados e tratados durante 11 dias, avaliando-se, em seguida, o efeito das drogas na variaÃÃo de massa corpÃrea e no Ãndice de perda Ãssea, alÃm de estudo histopatolÃgico do tecido Ãsseo e da gengiva. Na avaliaÃÃo da variaÃÃo da massa corpÃrea, observou-se que, com &#945;, &#946;-amirina e com lumiracoxibe ocorreu aumento no ganho de peso na massa corpÃrea, ao passo que, com a dexametasona, ocorreu diminuiÃÃo, quando comparados com o grupo normal (p<0,05). Em relaÃÃo ao Ãndice de perda Ãssea, observou-se que &#945;, &#946;-amirina 5 mg/kg nÃo preveniu a perda Ãssea, nÃo causando, no entanto, aumento, o que ocorreu na concentraÃÃo de 10 mg/kg e nos controles positivos, lumiracoxibe e dexametasona, quando comparados ao grupo falso-operado (p<0,01). Estes resultados permitem concluir que &#945;, &#946;-amirina modulou a inflamaÃÃo periodontal na fase aguda e demonstrou atividade antiinflamatÃria na periodontite nas fases aguda e crÃnica, mas nÃo mostrou capacidade para prevenir a perda Ãssea. Paralelamente a este estudo, investigou-se, tambÃm, o efeito da &#945;, &#946;-amirina em modelo de nocicepÃÃo orofacial induzida em ratos por formalina e capsaicina. Os animais foram prÃ-tratados com &#945;, &#946;-amirina (10, 30 e 100 mg/kg, i.p.) ou veÃculo (Tween 80, 3%), recebendo, em seguida, injeÃÃo de formalina (1,5 %,20 &#956;l) ou capsaicina (20 Âl, 1,5 &#956;g) na parte central da vibrissa direita. ApÃs a anÃlise dos dados, concluiu-se que a &#945;, &#946;-amirina exerceu atividade antinociceptiva no modelo de nocicepÃÃo orofacial induzida por capsaicina e formalina. / This study evaluated the triterpene pentaclycle &#945;- Ã-amyrin anti-inflammatory potential on the stages of periodontitis, acute and chronic, in rats. The periodontitis was induced through ligature placement around the second left upper molar. Rats (n=8) were treated with &#945;, &#946;-amyrin (5 and 10 mg/kg, v.o). Sham-operated and positive-controls (lumiracoxibe 20 mg/kg, v.o. and dexametasone, 1 mg/kg, i.p.) were included. The TNF-alfa levels in the plasma were evaluated and gingival tissues analyzed for myeloperoxidase (MPO) and thiobarbituric acid-reactive substances (TBARS). Both &#945;, &#946;-amyrin and dexametasone decreased the levels of TNF-alfa, MPO and TBARS. In chronic stage, the animals were observed and treated for a period of 11 days, in which the rats received the same drugs and were evaluated regarding their body mass variation and bone loss index, besides, were submitted to histopathological study of bone and gingival tissues. In the evaluation of the body mass variation, &#945;, &#946;-Amyrin and lumiracoxibe caused an increase in the weight gain, while a decrease occurred in rats treated with dexametasone when compared with the normal group (p<0.05). In relation to bone loss index, it was observed that &#945;, &#946;-Amyrin 5 mg/kg did not prevent bone loss, whereas a concentration of 10 mg/kg displayed an increase in bone loss; this increase also was perceived in the positive controls, lumiracoxibe and dexametasone, in relation to the sham-operated rats group (p<0.01). In conclusion, &#945;, &#946;-amyrin modulates acute phase periodontal inflammation and presents anti-inflammatory activity in both acute and chronic phases, but do not have the capacity to prevent bone loss. In parallel to this study, we also investigated the &#945;, &#946;-amyrin effect in model of orofacial pain induced in rats by formalin and capsaicin. The animals were pre-treated with &#945;, &#946;-amyrin (10, 30, and 100 mg/kg, i.p.), or vehicle (Tween 80, 3%), and than received either formalin (20 &#956;l, 1.5%) or capsaicin (20 Âl, 1.5 &#956;g) injection into the vibrissa central right side. After data analysis, it was concluded that &#945;, &#946;-amyrin exerts antinociception effect in experimental model of orofacial pain induced by capsaicin and formalin.

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