Abstract
Purpose
Overproduction of lipid peroxidation byproducts and disturbances in the antioxidant defense system have been implicated in the pathogenesis of several diseases, including prostate cancer. Although several studies have investigated the level of lipid peroxidation and antioxidants in prostate cancer, there are no reports on α-lipoic acid (ALA) in prostate cancer. Here we assessed the effects of ALA on the antioxidant system in prostate cancer cells.
Materials and Methods
PC-3, LNCaP, and RWPE-2 cell lines were used in this study. Redox factor (Ref)-1 protein was measured by Western blot analysis after treatment with ALA. Real-time polymerase chain reaction (RT-PCR) was performed to detect superoxide dismutase (SOD)-1 and -2, catalase, and glutathione peroxidase (GSH-Px) mRNA expression.
Results
Ref-1 was expressed in the PC-3, LNCaP, and RWPE-2 cell lines. The expression of Ref-1 protein was increased after treatment with 125, 250, and 500μM ALA in the PC-3 (p<0.05) and LNCaP (p>0.05) cells compared with the RWPE-2 cells at 48 hours. In PC-3 cells, the mRNA expression of SOD-1, SOD-2, catalase, and GSH-Px decreased at 24 and 48 hours dose-dependently compared with that in RWPE-2 cells (p<0.05). The mRNA expression of SOD-2, catalase, and GSH-Px in LNCaP cell decreased at 48 hours dose-dependently (p<0.05).
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