Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub

Detalhes bibliográficos
Autor(a) principal: Ferreira, Maria Augusta Drago
Data de Publicação: 2001
Tipo de documento: Tese
Idioma: por
Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
dARK ID: ark:/83112/001300000gc16
Texto Completo: http://www.repositorio.ufc.br/handle/riufc/64844
Resumo: Auxemma oncocalyx Taub. belongs to the Boraginaceae family and is native from the northeastem caatings where is know as “pau branco”. The stem bark of the tree is adstringent and popularly used in the treatment of wounds. The objective of the present work was to study toxicological effects and pharmacological activities of the hydrosoluble fraction isolated from the heartwood of A. oncocalyx. This fraction presents around 80 % of oncocalyxone A (quinone fraction). The LD50 of the quinone fraction (QF) in mice determined by the probit method was 182.16 mg/kg, i.p. and above of 500 mg/kg, o.d. The administration of QF for 15 days at the dose of 50 mg/kg, o.d. in rats, did not alter hematological or blood biochemical parameters . The pharmacological activities investigated were antiaggregating platelet, antioxidant, antiaedematogenic and antinociceptive using several experimental models. Results showed that QF presents a potent antiaggregating platelet activity in human platelets in vitro with different agonists (ADP, IC50 = 53.85 pg/ml; thrombin, IC50 = 93.76 pg/ml; collagen, IC50 = 56.57 pg/ml; arachidonic acid, IC50 = 86.07 pg/ml e adrenaline IC50 = 67.93 jig/ml). The activity was potentiated by aspirin (cyclooxynase inhibitor), pentoxifylline (methylxantine derivative and cAMP-dependent phosphodiesterase inhibitor), but not by L-arginine (NO precursor). The antiaggregating activity of QF was also observed in rat platelet in vitro in the presence of the following agonists: ADP and thrombin. However no activity was observed ex vivo. Surprisingly QF decreased bleeding time and contracted vascular smooth muscle (rat aorta). A potent antioxidant activity of QF was detected by inhibition of lipoperoxidation in rat brain homogenates, as determined by the production of substance reactive to the thiobarbituric acid (TBARS, Q1/2 = 1.64 pg/ml) and chemiluminescence (Q1Z2 = 2.06 jag/ml). However QF exerted a week activity on the model of CCl4-induced hepatotoxicity in rats as determined by measurement of ALT, AST activities and TBARS besides histopathological studies. The hepatoprotective effect of QF manifested itself more intensely in the model of prolongation by CCL4 of the barbiturate sleeping time in mice. Antinociceptive and antiedematogenic activities were also observed after QF administration, in the tests of abdominal contortion by acetic acid, formalin and hot-plate in mice (antinociceptive activity) and carrageenan and dextran-induced rat paw edema (antiedematogenic activity). The antinociceptive activity was dose-dependent, predominantly peripheric and independent of the opioid system. Results from the present work show that QF presents antiplatelet, antiinflamatory and antioxidant activities among others and these actions are probably dependent upon free radicais scavenger ability of QF.
id UFC-7_6df68e1973a27f4c57701177f2f83505
oai_identifier_str oai:repositorio.ufc.br:riufc/64844
network_acronym_str UFC-7
network_name_str Repositório Institucional da Universidade Federal do Ceará (UFC)
repository_id_str
spelling Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx TaubPlantas MedicinaisEuphorbiaceaeQuinonasAuxemma oncocalyx Taub. belongs to the Boraginaceae family and is native from the northeastem caatings where is know as “pau branco”. The stem bark of the tree is adstringent and popularly used in the treatment of wounds. The objective of the present work was to study toxicological effects and pharmacological activities of the hydrosoluble fraction isolated from the heartwood of A. oncocalyx. This fraction presents around 80 % of oncocalyxone A (quinone fraction). The LD50 of the quinone fraction (QF) in mice determined by the probit method was 182.16 mg/kg, i.p. and above of 500 mg/kg, o.d. The administration of QF for 15 days at the dose of 50 mg/kg, o.d. in rats, did not alter hematological or blood biochemical parameters . The pharmacological activities investigated were antiaggregating platelet, antioxidant, antiaedematogenic and antinociceptive using several experimental models. Results showed that QF presents a potent antiaggregating platelet activity in human platelets in vitro with different agonists (ADP, IC50 = 53.85 pg/ml; thrombin, IC50 = 93.76 pg/ml; collagen, IC50 = 56.57 pg/ml; arachidonic acid, IC50 = 86.07 pg/ml e adrenaline IC50 = 67.93 jig/ml). The activity was potentiated by aspirin (cyclooxynase inhibitor), pentoxifylline (methylxantine derivative and cAMP-dependent phosphodiesterase inhibitor), but not by L-arginine (NO precursor). The antiaggregating activity of QF was also observed in rat platelet in vitro in the presence of the following agonists: ADP and thrombin. However no activity was observed ex vivo. Surprisingly QF decreased bleeding time and contracted vascular smooth muscle (rat aorta). A potent antioxidant activity of QF was detected by inhibition of lipoperoxidation in rat brain homogenates, as determined by the production of substance reactive to the thiobarbituric acid (TBARS, Q1/2 = 1.64 pg/ml) and chemiluminescence (Q1Z2 = 2.06 jag/ml). However QF exerted a week activity on the model of CCl4-induced hepatotoxicity in rats as determined by measurement of ALT, AST activities and TBARS besides histopathological studies. The hepatoprotective effect of QF manifested itself more intensely in the model of prolongation by CCL4 of the barbiturate sleeping time in mice. Antinociceptive and antiedematogenic activities were also observed after QF administration, in the tests of abdominal contortion by acetic acid, formalin and hot-plate in mice (antinociceptive activity) and carrageenan and dextran-induced rat paw edema (antiedematogenic activity). The antinociceptive activity was dose-dependent, predominantly peripheric and independent of the opioid system. Results from the present work show that QF presents antiplatelet, antiinflamatory and antioxidant activities among others and these actions are probably dependent upon free radicais scavenger ability of QF.A espécie Auxemma oncocalyx Taub. pertencente a família Boraginaceae é característica do sertão nordestino onde é conhecida como pau branco. As cascas dessa árvore são adstringentes e popularmente utilizadas no tratamento de cortes e feridas. O objetivo do presente trabalho foi o de estudar efeitos tóxicos e atividades farmacológicas da fração hidrossolúvel obtida do cerne (caule) de A. oncocalyx, constituída em cerca de 80% pela oncocalixona A (fração quinona). A DL50 da fração quinona (FQ) para camundongos, determinada pelo método dos probitos foi de 182,16 mg/kg, i.p. e acima de 500 mg/kg, v.o. A administração de FQ por 15 dias na dose de 50 mg/kg, v.o. a ratos não alterou parâmetros hematológicos ou bioquímicos do sangue. As atividades farmacológicas investigadas foram: antiagregante plaquetária, antioxidante, antiedematogênica e antinociceptiva, utilizando vários modelos experimentais. Os resultados mostraram que FQ apresenta potente atividade antiagregante plaquetária em plaquetas humanas in vitro, frente a diferentes agonistas (ADP, CI50 = 53,85 pg/ml; trombina, CI50 = 93,76 pg/ml; colágeno, CI50 = 56,57 pg/ml; ácido araquidônico, CI50 = 86,07 pg/ml e adrenalina, CI50 = 67,93 pg/ml). Esse efeito foi potencializado pela presença de aspirina (inibidor de ciclooxigenase), e de pentoxifilina (inibidor de fosfodiesterase de AMPc), porém não pela L-arginina (substrato para a síntese de óxido nítrico). O efeito antiagregante plaquetário da FQ foi observado também em plaquetas de rato in vitro, frente aos agonistas: ADP e trombina, porém não ex vivo. Ao contrário do esperado, a FQ diminuiu o tempo de sangramento e contraiu a musculatura lisa vascular (aorta de ratos). Potente atividade antioxidante de FQ foi também detectada através da inibição de lipoperoxidação em homogeneizados de cérebro de ratos in vitro, determinada pela produção de substâncias reativas ao ácido tiobarbitúrico (TBARS, Q1/2 = 1,64 pg/ml) e quimiluminescência (QL = 2,06 pg/ml). Contudo, a FQ exerceu uma fraca ação protetora no modelo de hepatotoxicidade induzida pelo CCI4 em ratos, determinada pelas atividades de ALT e AST, TBARS e observação histopatológica. A ação hepatoprotetora de FQ manifestou-se de forma mais intensa no modelo de prolongamento pelo tetracloreto de carbono (CCI4) do tempo de sono barbitúrico em camundongos. As atividades antinociceptiva e antiinflamatória de FQ foram também observadas nos testes de contorções abdominais pelo ácido acético e formalina em camundongos (atividade antinociceptiva) e de edema de pata induzido pela carragenina e dextrano em ratos (atividade antiedematogênica). A atividade antinociceptiva é dose- dependente, predominante periférica e independente do sistema opióide. Os resultados desse trabalho nos permitiram concluir que FQ apresenta atividades antiagregante plaquetária, antiinflamatória e antioxidante entre outras e provavelmente essas ações dependem pelo menos em parte de sua capacidade sequestradora de radicais livres.Viana , Glauce Socorro de BarrosFerreira, Maria Augusta Drago2022-04-05T14:04:03Z2022-04-05T14:04:03Z2001info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisapplication/pdfFERREIRA, Maria Augusta Drago. Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub. 2001. 226 f. Tese (Doutorado em Farmacologia) - Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza, 2001. Disponível em: http://www.repositorio.ufc.br/handle/riufc/64844. Acesso em: 05/04/2022.http://www.repositorio.ufc.br/handle/riufc/64844ark:/83112/001300000gc16porreponame:Repositório Institucional da Universidade Federal do Ceará (UFC)instname:Universidade Federal do Ceará (UFC)instacron:UFCinfo:eu-repo/semantics/openAccess2022-04-05T14:05:29Zoai:repositorio.ufc.br:riufc/64844Repositório InstitucionalPUBhttp://www.repositorio.ufc.br/ri-oai/requestbu@ufc.br || repositorio@ufc.bropendoar:2024-09-11T18:38:48.603832Repositório Institucional da Universidade Federal do Ceará (UFC) - Universidade Federal do Ceará (UFC)false
dc.title.none.fl_str_mv Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
title Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
spellingShingle Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
Ferreira, Maria Augusta Drago
Plantas Medicinais
Euphorbiaceae
Quinonas
title_short Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
title_full Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
title_fullStr Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
title_full_unstemmed Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
title_sort Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub
author Ferreira, Maria Augusta Drago
author_facet Ferreira, Maria Augusta Drago
author_role author
dc.contributor.none.fl_str_mv Viana , Glauce Socorro de Barros
dc.contributor.author.fl_str_mv Ferreira, Maria Augusta Drago
dc.subject.por.fl_str_mv Plantas Medicinais
Euphorbiaceae
Quinonas
topic Plantas Medicinais
Euphorbiaceae
Quinonas
description Auxemma oncocalyx Taub. belongs to the Boraginaceae family and is native from the northeastem caatings where is know as “pau branco”. The stem bark of the tree is adstringent and popularly used in the treatment of wounds. The objective of the present work was to study toxicological effects and pharmacological activities of the hydrosoluble fraction isolated from the heartwood of A. oncocalyx. This fraction presents around 80 % of oncocalyxone A (quinone fraction). The LD50 of the quinone fraction (QF) in mice determined by the probit method was 182.16 mg/kg, i.p. and above of 500 mg/kg, o.d. The administration of QF for 15 days at the dose of 50 mg/kg, o.d. in rats, did not alter hematological or blood biochemical parameters . The pharmacological activities investigated were antiaggregating platelet, antioxidant, antiaedematogenic and antinociceptive using several experimental models. Results showed that QF presents a potent antiaggregating platelet activity in human platelets in vitro with different agonists (ADP, IC50 = 53.85 pg/ml; thrombin, IC50 = 93.76 pg/ml; collagen, IC50 = 56.57 pg/ml; arachidonic acid, IC50 = 86.07 pg/ml e adrenaline IC50 = 67.93 jig/ml). The activity was potentiated by aspirin (cyclooxynase inhibitor), pentoxifylline (methylxantine derivative and cAMP-dependent phosphodiesterase inhibitor), but not by L-arginine (NO precursor). The antiaggregating activity of QF was also observed in rat platelet in vitro in the presence of the following agonists: ADP and thrombin. However no activity was observed ex vivo. Surprisingly QF decreased bleeding time and contracted vascular smooth muscle (rat aorta). A potent antioxidant activity of QF was detected by inhibition of lipoperoxidation in rat brain homogenates, as determined by the production of substance reactive to the thiobarbituric acid (TBARS, Q1/2 = 1.64 pg/ml) and chemiluminescence (Q1Z2 = 2.06 jag/ml). However QF exerted a week activity on the model of CCl4-induced hepatotoxicity in rats as determined by measurement of ALT, AST activities and TBARS besides histopathological studies. The hepatoprotective effect of QF manifested itself more intensely in the model of prolongation by CCL4 of the barbiturate sleeping time in mice. Antinociceptive and antiedematogenic activities were also observed after QF administration, in the tests of abdominal contortion by acetic acid, formalin and hot-plate in mice (antinociceptive activity) and carrageenan and dextran-induced rat paw edema (antiedematogenic activity). The antinociceptive activity was dose-dependent, predominantly peripheric and independent of the opioid system. Results from the present work show that QF presents antiplatelet, antiinflamatory and antioxidant activities among others and these actions are probably dependent upon free radicais scavenger ability of QF.
publishDate 2001
dc.date.none.fl_str_mv 2001
2022-04-05T14:04:03Z
2022-04-05T14:04:03Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/doctoralThesis
format doctoralThesis
status_str publishedVersion
dc.identifier.uri.fl_str_mv FERREIRA, Maria Augusta Drago. Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub. 2001. 226 f. Tese (Doutorado em Farmacologia) - Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza, 2001. Disponível em: http://www.repositorio.ufc.br/handle/riufc/64844. Acesso em: 05/04/2022.
http://www.repositorio.ufc.br/handle/riufc/64844
dc.identifier.dark.fl_str_mv ark:/83112/001300000gc16
identifier_str_mv FERREIRA, Maria Augusta Drago. Estudo de efeitos tóxicos e atividades farmacológicas da fração quinona de Auxemma oncocalyx Taub. 2001. 226 f. Tese (Doutorado em Farmacologia) - Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza, 2001. Disponível em: http://www.repositorio.ufc.br/handle/riufc/64844. Acesso em: 05/04/2022.
ark:/83112/001300000gc16
url http://www.repositorio.ufc.br/handle/riufc/64844
dc.language.iso.fl_str_mv por
language por
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv reponame:Repositório Institucional da Universidade Federal do Ceará (UFC)
instname:Universidade Federal do Ceará (UFC)
instacron:UFC
instname_str Universidade Federal do Ceará (UFC)
instacron_str UFC
institution UFC
reponame_str Repositório Institucional da Universidade Federal do Ceará (UFC)
collection Repositório Institucional da Universidade Federal do Ceará (UFC)
repository.name.fl_str_mv Repositório Institucional da Universidade Federal do Ceará (UFC) - Universidade Federal do Ceará (UFC)
repository.mail.fl_str_mv bu@ufc.br || repositorio@ufc.br
_version_ 1818373770520297472