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Alpha Amyrin
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Joao B Calixto – One of the best experts on this subject based on the ideXlab platform.
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mechanisms underlying the inhibitory actions of the pentacyclic triterpene Alpha Amyrin in the mouse skin inflammation induced by phorbol ester 12 o tetradecanoylphorbol 13 acetate
European Journal of Pharmacology, 2007Co-Authors: Rodrigo Medeiros, Michel Fleith Otuki, Maria Christina W Avellar, Joao B CalixtoAbstract:The present study evaluated some of the mechanisms through which Alpha–Amyrin, a pentacyclic triterpene isolated from Protium Kleinii and other plants, exerts its effects against 12-O-tetradecanoylphorbol-acetate (TPA)-induced skin inflammation in mice. Topical application of Alpha–Amyrin (0.1-1 mg/ear) dose-dependently inhibited TPA-induced increase of prostaglandin E2 (PGE2) levels. In contrast with the selective cyclooxygenase (COX)-1 SC560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethylpyrazole] or COX-2 rofecoxib inhibitors, Alpha–Amyrin failed to alter either COX-1 or COX-2 activities in vitro. Western blot analysis revealed that Alpha–Amyrin dose-dependently inhibited TPA-induced COX-2 expression in the mouse skin. The evaluation of nuclear factor-kappaB (NF-kappaB) pathway revealed that topical treatment with Alpha–Amyrin is able to prevent IkappaB Alpha degradation, p65/RelA phosphorylation and NF-kappaB activation. Moreover, Alpha–Amyrin given topically dose-dependently inhibited the activation of upstream protein kinases, namely extracellular signal-regulated protein kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and protein kinase C (PKC)Alpha, following topical TPA treatment. Collectively, present results suggest that topical skin application of Alpha–Amyrin exerts a strong and rapid onset inhibition of TPA-induced inflammation. These effects seem to be associated with the suppression of skin PGE2 levels by mechanisms involving the suppression of COX-2 expression, via inhibition of upstream protein kinases–namely ERK, p38 MAPK and PKCAlpha–and blocking of NF-kappaB activation. These results indicate that Alpha–Amyrin-derivative could be potentially relevant for the development of a topical agent for the management of inflammatory diseases.
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topical antiinflammatory effects of the ether extract from protium kleinii and α Amyrin pentacyclic triterpene
European Journal of Pharmacology, 2005Co-Authors: Michel Fleith Otuki, Fabiana Vieiralima, Angela Malheiros, Rosendo A Yunes, Joao B CalixtoAbstract:Protium kleinii (Burseraceae), a native Brazilian medicinal plant is claimed to be useful to treat some inflammatory states. Now we reported that topical application of either the ether extract or the main active constituent from P. kleinii the pentacyclic triterpene Alpha–Amyrin, all caused a dose-related inhibition of both ear oedema (ID50 values are 0.55 and 0.31 mg/ear, respectively) and influx of polymorphonuclear cells (ID50 values are 0.72 and 0.45 mg/ear, respectively) in response to topical application of 12-O-tetradecanoylphorbol-acetate (TPA) in the of mice ear. In terms of the efficacy, the maximal obtained inhibition for both ear oedema and neutrophil influx was very similar to that produced by the topical application of the steroidal antiinflammatory drug dexamethasone (DE; with inhibition of 70+/-5%, 66+/-3%, and 87+/-4% for oedema and 83+/-6%, 73+/-5%, and 91+/-3% for neutrophil influx, for the ether extract, Alpha–Amyrin, and dexamethasone, respectively). Likewise, both the ether extract and Alpha–Amyrin given topically dose-dependently prevented the increase of the proinflammatory cytokine interleukin-1beta levels in response to topical application of TPA. The calculated mean ID50 values are 1.81 and 0.53 mg/ear, respectively. Again, the efficacy of the extract and Alpha–Amyrin was very similar to that produced by dexamethasone (63+/-6%, 61+/-5%, and 74+/-5%, respectively). In marked contrast to phenidone, a lipo and cyclooxygenase inhibitor, neither the ether extract nor the Alpha–Amyrin inhibited arachidonic acid-mediated ear oedema in mice. Collectively, these results indicate that the active constituents present in the ether extract of P. kleinii including the pentacyclic triterpene Alpha–Amyrin are good candidates to develop a skin permeable antiinflammatory drug.
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Topical antiinflammatory effects of the ether extract from Protium kleinii and Alpha–Amyrin pentacyclic triterpene.
European journal of pharmacology, 2004Co-Authors: Michel Fleith Otuki, Angela Malheiros, Rosendo A Yunes, Fabiana Vieira-lima, Joao B CalixtoAbstract:Protium kleinii (Burseraceae), a native Brazilian medicinal plant is claimed to be useful to treat some inflammatory states. Now we reported that topical application of either the ether extract or the main active constituent from P. kleinii the pentacyclic triterpene Alpha–Amyrin, all caused a dose-related inhibition of both ear oedema (ID50 values are 0.55 and 0.31 mg/ear, respectively) and influx of polymorphonuclear cells (ID50 values are 0.72 and 0.45 mg/ear, respectively) in response to topical application of 12-O-tetradecanoylphorbol-acetate (TPA) in the of mice ear. In terms of the efficacy, the maximal obtained inhibition for both ear oedema and neutrophil influx was very similar to that produced by the topical application of the steroidal antiinflammatory drug dexamethasone (DE; with inhibition of 70+/-5%, 66+/-3%, and 87+/-4% for oedema and 83+/-6%, 73+/-5%, and 91+/-3% for neutrophil influx, for the ether extract, Alpha–Amyrin, and dexamethasone, respectively). Likewise, both the ether extract and Alpha–Amyrin given topically dose-dependently prevented the increase of the proinflammatory cytokine interleukin-1beta levels in response to topical application of TPA. The calculated mean ID50 values are 1.81 and 0.53 mg/ear, respectively. Again, the efficacy of the extract and Alpha–Amyrin was very similar to that produced by dexamethasone (63+/-6%, 61+/-5%, and 74+/-5%, respectively). In marked contrast to phenidone, a lipo and cyclooxygenase inhibitor, neither the ether extract nor the Alpha–Amyrin inhibited arachidonic acid-mediated ear oedema in mice. Collectively, these results indicate that the active constituents present in the ether extract of P. kleinii including the pentacyclic triterpene Alpha–Amyrin are good candidates to develop a skin permeable antiinflammatory drug.
Michel Fleith Otuki – One of the best experts on this subject based on the ideXlab platform.
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mechanisms underlying the inhibitory actions of the pentacyclic triterpene Alpha Amyrin in the mouse skin inflammation induced by phorbol ester 12 o tetradecanoylphorbol 13 acetate
European Journal of Pharmacology, 2007Co-Authors: Rodrigo Medeiros, Michel Fleith Otuki, Maria Christina W Avellar, Joao B CalixtoAbstract:The present study evaluated some of the mechanisms through which Alpha–Amyrin, a pentacyclic triterpene isolated from Protium Kleinii and other plants, exerts its effects against 12-O-tetradecanoylphorbol-acetate (TPA)-induced skin inflammation in mice. Topical application of Alpha–Amyrin (0.1-1 mg/ear) dose-dependently inhibited TPA-induced increase of prostaglandin E2 (PGE2) levels. In contrast with the selective cyclooxygenase (COX)-1 SC560 [5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-trifluoromethylpyrazole] or COX-2 rofecoxib inhibitors, Alpha–Amyrin failed to alter either COX-1 or COX-2 activities in vitro. Western blot analysis revealed that Alpha–Amyrin dose-dependently inhibited TPA-induced COX-2 expression in the mouse skin. The evaluation of nuclear factor-kappaB (NF-kappaB) pathway revealed that topical treatment with Alpha–Amyrin is able to prevent IkappaB Alpha degradation, p65/RelA phosphorylation and NF-kappaB activation. Moreover, Alpha–Amyrin given topically dose-dependently inhibited the activation of upstream protein kinases, namely extracellular signal-regulated protein kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and protein kinase C (PKC)Alpha, following topical TPA treatment. Collectively, present results suggest that topical skin application of Alpha–Amyrin exerts a strong and rapid onset inhibition of TPA-induced inflammation. These effects seem to be associated with the suppression of skin PGE2 levels by mechanisms involving the suppression of COX-2 expression, via inhibition of upstream protein kinases–namely ERK, p38 MAPK and PKCAlpha–and blocking of NF-kappaB activation. These results indicate that Alpha–Amyrin-derivative could be potentially relevant for the development of a topical agent for the management of inflammatory diseases.
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topical antiinflammatory effects of the ether extract from protium kleinii and α Amyrin pentacyclic triterpene
European Journal of Pharmacology, 2005Co-Authors: Michel Fleith Otuki, Fabiana Vieiralima, Angela Malheiros, Rosendo A Yunes, Joao B CalixtoAbstract:Protium kleinii (Burseraceae), a native Brazilian medicinal plant is claimed to be useful to treat some inflammatory states. Now we reported that topical application of either the ether extract or the main active constituent from P. kleinii the pentacyclic triterpene Alpha–Amyrin, all caused a dose-related inhibition of both ear oedema (ID50 values are 0.55 and 0.31 mg/ear, respectively) and influx of polymorphonuclear cells (ID50 values are 0.72 and 0.45 mg/ear, respectively) in response to topical application of 12-O-tetradecanoylphorbol-acetate (TPA) in the of mice ear. In terms of the efficacy, the maximal obtained inhibition for both ear oedema and neutrophil influx was very similar to that produced by the topical application of the steroidal antiinflammatory drug dexamethasone (DE; with inhibition of 70+/-5%, 66+/-3%, and 87+/-4% for oedema and 83+/-6%, 73+/-5%, and 91+/-3% for neutrophil influx, for the ether extract, Alpha–Amyrin, and dexamethasone, respectively). Likewise, both the ether extract and Alpha–Amyrin given topically dose-dependently prevented the increase of the proinflammatory cytokine interleukin-1beta levels in response to topical application of TPA. The calculated mean ID50 values are 1.81 and 0.53 mg/ear, respectively. Again, the efficacy of the extract and Alpha–Amyrin was very similar to that produced by dexamethasone (63+/-6%, 61+/-5%, and 74+/-5%, respectively). In marked contrast to phenidone, a lipo and cyclooxygenase inhibitor, neither the ether extract nor the Alpha–Amyrin inhibited arachidonic acid-mediated ear oedema in mice. Collectively, these results indicate that the active constituents present in the ether extract of P. kleinii including the pentacyclic triterpene Alpha–Amyrin are good candidates to develop a skin permeable antiinflammatory drug.
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Topical antiinflammatory effects of the ether extract from Protium kleinii and Alpha–Amyrin pentacyclic triterpene.
European journal of pharmacology, 2004Co-Authors: Michel Fleith Otuki, Angela Malheiros, Rosendo A Yunes, Fabiana Vieira-lima, Joao B CalixtoAbstract:Protium kleinii (Burseraceae), a native Brazilian medicinal plant is claimed to be useful to treat some inflammatory states. Now we reported that topical application of either the ether extract or the main active constituent from P. kleinii the pentacyclic triterpene Alpha–Amyrin, all caused a dose-related inhibition of both ear oedema (ID50 values are 0.55 and 0.31 mg/ear, respectively) and influx of polymorphonuclear cells (ID50 values are 0.72 and 0.45 mg/ear, respectively) in response to topical application of 12-O-tetradecanoylphorbol-acetate (TPA) in the of mice ear. In terms of the efficacy, the maximal obtained inhibition for both ear oedema and neutrophil influx was very similar to that produced by the topical application of the steroidal antiinflammatory drug dexamethasone (DE; with inhibition of 70+/-5%, 66+/-3%, and 87+/-4% for oedema and 83+/-6%, 73+/-5%, and 91+/-3% for neutrophil influx, for the ether extract, Alpha–Amyrin, and dexamethasone, respectively). Likewise, both the ether extract and Alpha–Amyrin given topically dose-dependently prevented the increase of the proinflammatory cytokine interleukin-1beta levels in response to topical application of TPA. The calculated mean ID50 values are 1.81 and 0.53 mg/ear, respectively. Again, the efficacy of the extract and Alpha–Amyrin was very similar to that produced by dexamethasone (63+/-6%, 61+/-5%, and 74+/-5%, respectively). In marked contrast to phenidone, a lipo and cyclooxygenase inhibitor, neither the ether extract nor the Alpha–Amyrin inhibited arachidonic acid-mediated ear oedema in mice. Collectively, these results indicate that the active constituents present in the ether extract of P. kleinii including the pentacyclic triterpene Alpha–Amyrin are good candidates to develop a skin permeable antiinflammatory drug.
Dionéia Camilo Rodrigues De Oliveira – One of the best experts on this subject based on the ideXlab platform.
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Análise comparativa de triterpenóides de Mikania cordifolia coletada em quatro locais diferentes
Universidade de São Paulo. Faculdade de Ciências Farmacêuticas, 2006Co-Authors: Patrícia Abrão De Oliveira, Turatti, Izabel Cristina Casanova, Dionéia Camilo Rodrigues De OliveiraAbstract:The species Mikania cordifolia is distributed across America and widely found throughout Brazilian territory, where is popularly used against snake bites. Methanolic and dichloromethanic extracts prepared from M. cordifolia Robinson collected from four different locations in Brazil were submitted to liquid-liquid extraction and the hexanic phase and residues obtained from this step were analyzed for triterpenoids by gas chromatography. The specimens from Ribeirão Preto-SP and São Carlos-SP showed similar triterpenoid composition: Alpha–Amyrin, lupeol, lupenone, Alpha–Amyrin acetate, beta-Amyrin acetate, lupeol acetate, taraxasterol acetate, campesterol and beta-sitosterol. Besides these triterpenoids, the specimen from Campos de Jordão-SP presented 11-oxours-12-ene, 11-oxoolean-12-ene and taraxerol acetate, and from Monte Verde, epitaraxerol e taraxerol acetate. The triterpene friedelin could be found in specimens from Ribeirão Preto and São Carlos.A espécie Mikania cordifolia distribui-se por toda a América e é amplamente encontrada em quase todo o território brasileiro, onde é utilizada popularmente contra mordidas de serpentes. Extratos metanólicos e diclorometânicos preparados a partir e M. cordifolia Robinson coletadas em quatro locais diferentes do Brasil foram submetidos à extração líquido-líquido e os extratos hexânicos e resíduos obtidos nesta etapa foram analisados para a pesquisa de triterpenóides por cromatografia em fase gasosa. Os espécimes coletados em Ribeirão Preto-SP e São Carlos-SP apresentaram os triterpenóides beta-amirina, lupeol, lupenona, acetato de alfa-amirina, acetato de beta-amirina, acetato de lupeol, acetato de taraxasterol, campesterol e beta-sitosterol na suas composições. Além destes trierpenóides, o espécime de Campos de Jordão-SP apresentou 11-oxours-12-eno, 11-oxoolean-12-eno e acetato de taraxerol e, o de Monte verde-MG, epitaraxerol e acetato de taraxerol. A friedelina foi observada apenas nas amostras de Ribeirão Preto-SP e São Carlos-SP
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Estudo fitoquímico de Mikania pseudohoffmanianna G. M. Barroso ex W. C. Holmes
Universidade de São Paulo. Faculdade de Ciências Farmacêuticas, 2006Co-Authors: Janaina Moreira De Souza, Taleb-contini, Silvia Helena, Dionéia Camilo Rodrigues De OliveiraAbstract:This work describes the fractionation of methanol and dichloromethane extracts of aerial parts from the Mikania pseudohoffmanniana G. M. Barroso ex W. C. Holmes. The phytochemical study of extracts led to isolation and the identification of 16 known compounds, including: steroids: campesterol, stigmasterol and beta-sitosterol, diterpenes: ent-15beta-E-cinnamoyloxy-kaur-16-en-19-oic acid, ent-15beta-Z-cinnamoyloxy-kaur-16-en-19-oic acid and ent-kaur-16-en-19-oic acid, triterpenes: Alpha–Amyrin, beta-Amyrin, Alpha–Amyrin acetate, beta-Amyrin acetate, lupeol, lupeol acetate and friedelin, coumarin: scopoletin, flavonoid: quercetin and caffeoyl quinic acid derivative: 4,5-di-O-[E]-caffeoyl quinic acid.O fracionamento dos extratos diclorometânico e metanólico das partes aéreas de Mikania pseudohoffmanniana G. M. Barroso ex W. C. Holmes resultou na identificação de 16 substâncias: os esteróides: campesterol, estigmasterol e beta-sitosterol; os diterpenos: ácido ent-15beta-E-cinamoiloxi-caur-16-en-19-óico, ácido ent-15beta-Z-cinamoiloxi-caur-16-en-19-óico e ácido ent-caur-16-en-19-óico; os triterpenos: alfa-amirina, beta-amirina, acetato de alfa-amirina, acetato de beta-amirina, lupeol, acetato de lupeol e friedelina; a cumarina: escopoletina; o flavonóide: quercetina e o derivado do ácido cafeoilquínico: 4,5-di-O-[E] -cafeoilquínico
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Phytochemical study of Mikania pseudohoffmanianna G. M. Barroso ex W. C. Holmes Estudo fitoquímico de Mikania pseudohoffmanianna G. M. Barroso ex W. C. Holmes
Universidade de São Paulo, 2006Co-Authors: Janaina Moreira De Souza, Silvia Helena Taleb-contini, Dionéia Camilo Rodrigues De OliveiraAbstract:This work describes the fractionation of methanol and dichloromethane extracts of aerial parts from the Mikania pseudohoffmanniana G. M. Barroso ex W. C. Holmes. The phytochemical study of extracts led to isolation and the identification of 16 known compounds, including: steroids: campesterol, stigmasterol and beta-sitosterol, diterpenes: ent-15beta-E-cinnamoyloxy-kaur-16-en-19-oic acid, ent-15beta-Z-cinnamoyloxy-kaur-16-en-19-oic acid and ent-kaur-16-en-19-oic acid, triterpenes: Alpha–Amyrin, beta-Amyrin, Alpha–Amyrin acetate, beta-Amyrin acetate, lupeol, lupeol acetate and friedelin, coumarin: scopoletin, flavonoid: quercetin and caffeoyl quinic acid derivative: 4,5-di-O-[E]-caffeoyl quinic acid.O fracionamento dos extratos diclorometânico e metanólico das partes aéreas de Mikania pseudohoffmanniana G. M. Barroso ex W. C. Holmes resultou na identificação de 16 substâncias: os esteróides: campesterol, estigmasterol e beta-sitosterol; os diterpenos: ácido ent-15beta-E-cinamoiloxi-caur-16-en-19-óico, ácido ent-15beta-Z-cinamoiloxi-caur-16-en-19-óico e ácido ent-caur-16-en-19-óico; os triterpenos: alfa-amirina, beta-amirina, acetato de alfa-amirina, acetato de beta-amirina, lupeol, acetato de lupeol e friedelina; a cumarina: escopoletina; o flavonóide: quercetina e o derivado do ácido cafeoilquínico: 4,5-di-O-[E] -cafeoilquínico