title: Antiapoptotic and Antioxidant Properties of Orthosiphon stamineus Benth (Cat's Whiskers): Intervention in the Bcl-2-Mediated Apoptotic Pathway.
abstract: Antiapoptotic and antioxidant activities of aqueous-methanolic extract (CAME) of Orthosiphonstamineus Benth(OS), and its hexane (HF), chloroform (CF), n-butanol (NBF), ethyl acetate (EAF) and water (WF) fractions were investigated. Antioxidant properties were evaluated using the assays of Folin-Ciocalteu, aluminiumtrichloride, β-carotene bleaching and DPPH. The role of OS against hydrogen peroxide induced apoptosis on MDA-M231 epithelial cells was examined using MTT assay, phase contrast microscope, colorimetric assay of caspase-3, western blot and quantitative real-time PCR. Results showed that EAF showed the highest total phenolic content followed by CAME, NBF, WF, CF and HF, respectively. Flavonoid content was in the order of the CF > EAF > HF > CAME > NBF > WF. The IC(50) values on DPPH assay for different extract/fractions were 126.2 ± 23, 31.25 ± 1.2, 15.25 ± 2.3, 13.56 ± 1.9, 23.0 ± 3.2, and 16.66 ± 1.5 μg/ml for HF, CF, EAF, NBF, WF and CAME, respectively. OSreduced the oxidation of β-carotene by hydroperoxides. Cell death was dose-dependently inhibited by pretreatment with OS. Caspase-3 and distinct morphological features suggest the anti-apoptotic activities of OS. This plant not only increased the expression of Bcl-2, but also decreased Bax expression, and ultimately reduced H(2)O(2)-induced apoptosis. The current results showed that phenolics may provide health and nutritional benefits.
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Siddig Ibrahim
authors.initials: SI
authors.lastname: Abdelwahab
authors.forename: Syam
authors.initials: S
authors.lastname: Mohan
authors.forename: Manal
authors.initials: M
authors.lastname: Mohamed Elhassan
authors.forename: Nabil
authors.initials: N
authors.lastname: Al-Mekhlafi
authors.forename: Abdelbasit Adam
authors.initials: AA
authors.lastname: Mariod
authors.forename: Ahmad Bustamam
authors.initials: AB
authors.lastname: Abdul
authors.forename: Mahmood Ameen
authors.initials: MA
authors.lastname: Abdulla
authors.forename: Khalid M
authors.initials: KM
authors.lastname: Alkharfy