Tempol effect on oxidative and mitochondrial markers in preclinical models for prostate cancer.

BACKGROUND: Tempol is a redox-cycling nitroxide considered a potent antioxidant. The present study investigated the tempol effects on oxidative stress and mitochondrial markers on prostate cancer (PCa).

METHODS: PC-3 and LnCaP cells were exposed to tempol. Cell viability test, western blot and Amplex Red analyses were performed. In vivo, five experimental groups evaluated tempol effects in the early (CT12 and TPL12 groups) and late stages (CT20, TPL20-I, and TLP20-II) of PCa development. The TPL groups were treated with 50 or 100 mg/kg tempol doses. Control groups received water as the vehicle. The ventral lobe of the prostate and the blood were collected and submitted to western blotting or enzymatic activity analyses.

RESULTS: In vitro, tempol decreased cell viability and differentially altered the H2 O2 content for PC-3 and LNCaP. Tempol increased SOD2 levels in both cell lines and did not alter Catalase protein levels. In vivo, tempol increased SOD2 levels in the early stage and did not change Catalase levels in the different PCa stages. Systemically, tempol decreased SOD2 levels in the late-stage and improved redox status in the early and late stages, which was confirmed by reduced LDH in tempol groups. Alterations on energetic metabolism and oxidative phosphorylation were observed in TRAMP model.

CONCLUSION: Tempol can be considered a beneficial therapy for PCa treatment considering its antioxidant and low toxicity properties, however the PCa progression must be evaluated to get successful therapy.