Revista Brasileira de Plantas Medicinais (Mar 2010)
Estudo químico e da atividade biológica cardiovascular do óleo essencial de folhas de Alpinia zerumbet (Pers.) B.L.Burtt & R.M.Sm. em ratos Phytochemistry and cardiovascular biological activity of the essential oil from leaves of Alpinia zerumbet (Pers.) B.L. Burtt & R.M.Sm. in rats
Abstract
A espécie vegetal Alpinia zerumbet (Pers.) B.L.Burtt & R.M. Sm. é popularmente empregada para o tratamento de diversas enfermidades, entre elas a hipertensão. Avaliar a composição química, a atividade antihipertensiva e ação na hipertrofia cardíaca do óleo essencial das folhas de Alpinia zerumbet (OEAZ) em ratos foram os objetivos deste estudo. O OEAZ, obtido por hidrodestilação em aparelho Clevenger, teve sua composição química analisada em cromatografia gasosa acoplada à espectrometria de massas (CG-EM). Foram identificados 14 constituintes, sendo terpinen-4-ol (37,45%) o majoritário, seguido pelos óxido de cariofileno (7,56%), trans-hidrato de sabineno (6,61%) e 1,8-cineol (4,02%). A avaliação cardiovascular foi feita após o tratamento crônico de ratos espontaneamente hipertensos (SHR) e seus respectivos controles, ratos Wistar-Kyoto (WKY). Os dados hemodinâmicos revelaram redução da pressão arterial média (PAM) no grupo tratado (SHRP: 160 ± 7 mm Hg; pAlpinia zerumbet (Pers.) B.L. Burtt & R.M.Sm. is traditionally employed to treat several diseases such as hypertension. The aim of this study was to evaluate the chemical composition, the anti-hypertensive activity and the capacity to reduce cardiac hypertrophy of the essential oil of A. zerumbet leaves (EOAZ) in rats. EOAZ was obtained through hydrodistillation in Clevenger apparatus and its chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS). Several constituents (14) were identified, terpen-4-ol (37.45%) being the major component, followed by caryophyllene oxide (7.56%), trans-sabinene hydrate (6.61%) and 1,8-cineol (4.02%). The cardiovascular effect was investigated after chronic treatment with spontaneously hypertensive rats (SHR) and their respective controls, Wistar-Kyoto rats (WKY). The treated group showed a lower mean arterial pressure (MAP) (SHRP: 160 ± 7 mm Hg; p<0.01) than the untreated group (SHR: 180 ± 5 mm Hg). The ratio of left ventricle-to-body weight (LV/BW) for SHRP was lower (2.504 ± 0.03 mg g-1; p<0.01) than that for SHR (2.162 ± 0.01 mg g-1), confirming the cardiac hypertrophy (CH) reduction. There were significant differences in MAP and CH between SHRP animals and control rats (WKY: 116 ± 2 mm Hg and WKYP: 119 ± 4 mm Hg; p<0.05. WKY: 2.152 ± 0.04 mg g-1 and WKYP: 2.168 ± 0.04 mg g-1; p<0.01), indicating that these values were not normalized. Those data showed that the chronic treatment with EOAZ reduces MAP and CH in SHR probably due to the presence of the compounds terpinen-4-ol and 1,8-cineol. Studies with higher doses or longer treatment periods are necessary to evaluate whether EOAZ can reduce the analyzed parameters (MAP and CH) to normal values.
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