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P3‐242: The role of autophagy in potentially therapeutic copper complexes
Author(s) -
Price Katherine A.,
Lim Sin Chun,
Patterson Brett,
Caragounis Aphrodite,
Volitakis Irene,
Cherny Robert,
Masters Colin L.,
Barnham Kevin J.,
Donnelly Paul S.,
Crouch Peter J.,
White Anthony R.
Publication year - 2009
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2009.04.1015
Subject(s) - autophagy , chemistry , confocal microscopy , microbiology and biotechnology , vacuole , intracellular , cytosol , organelle , fluorescence microscope , biochemistry , fluorescence , biology , cytoplasm , apoptosis , enzyme , physics , quantum mechanics
Background: b-amyloid (Ab), a main content of amyloid plaque, plays a key role in the pathogenesis of Alzheimer’s disease (AD). Ab induces neurotoxicity and cell death mainly through the production of reactive oxygen species (ROS). Garcinia mangostana L. (mangosteen, MS) has been recognized as a major source of natural antioxidant, xanthone, that could decrease ROS. However, its role in protection of Ab-induced apoptosis in neural cells remains unclear. Objective: To investigate the protective effect of MS extract on Ab-induced apoptosis in SK-N-SH cells. Methods: MS pericarp was extracted and standardized to contain certain amount of xanthone. Apoptosis in SK-N-SH cells were induced by 5-20 mM of Ab1-42. In parallel, MS extract (200-800 mg/ml) was preincubated (30 min) in cell culture before the induction by Ab1-42. The potential protective effects of MS extract were determined by evaluating cell morphology, cell viability using MTT test, ROS levels, caspase activity, apoptotic cell count, and cellular proteome. Results: The SK-N-SH cells showed cytotoxic changes after treatment with Ab1-42 in a dose-dependent manner. ROS levels were also significantly increased (approximately 5-10 folds), which corresponded with a decrease in cell viability (to w55-70% of the control), and an increase in caspase-3 activity (w2.5-fold of the control). All these Ab1-42-induced toxic effects were significantly reduced (almost completely) by the pretreatment with 400 mg/ml of MS extract. Interestingly, proteomic analysis using 2-D PAGE (n 1⁄4 5 gels/group) revealed 63 proteins spots whose levels were significantly altered by Ab1-42 induction. Among these, changes in 10 spots could be successfully prevented or recovered by the pretreatment with MS extract. All these altered proteins are subjected to identification by mass spectrometry (on-going). Conclusions: We have demonstrated significant protective effects of MS extract against Ab-induced ROS toxicity, increased caspase activity and apoptosis in SK-N-SH cells. Moreover, proteomic analysis revealed some proteins that might be responsible for these protective effects by MS extract. Characterizations of these proteins may lead to identification of novel therapeutic targets for successful prevention and/or decreasing the severity of AD.