Antioxidant activity of ginger extract as a daily supplement in cancer patients receiving adjuvant chemotherapy: a pilot study

Purpose: The aim of this study was to examine the antioxidant activity of ginger extract oral supplement in newly diagnosed cancer patients receiving adjuvant chemotherapy compared to placebo. Patients and methods: Newly diagnosed cancer patients receiving moderate-to-high emetogenic potential adjuvant chemotherapy were randomized to receive either a ginger extract (standardized 6-gingerol 20 mg/day) or a placebo 3 days prior to chemotherapy, which they continued daily. Oxidant/antioxidant parameters, including the activities of superoxide dismutase (SOD) and catalase (CAT) and levels of glutathione peroxidase (GPx), total glutathione (GSH/GSSG), lipid peroxidation products detected as malondialdehyde (MDA) and NO2/-NO3-, were measured at baseline and at days 1, 22, 43 and 64 after undergoing chemotherapy. Two-sided statistical analysis, with P < 0.05, was used to determine statistical significance. Results: A total of 43 patients were included in the study: 19 and 24 patients were randomly assigned to the ginger group and placebo group, respectively. Antioxidant activity parameters, including SOD, CAT, GPx and GSH/GSSG, were significantly increased at day 64 in the ginger group compared to those in the placebo group, while MDA and NO2-/NO(3)(-)levels were significantly decreased (P < 0.0001). When compared to the baseline, the activities of SOD and CAT and the levels of GPx and GSH/GSSG were significantly higher on day 64 (P = 0.01), while the blood levels of MDA and NO2-/NO(3)(-)were significantly decreased (P < 0.01). Conclusion: Daily supplement of ginger extract started 3 days prior to chemotherapy has been shown to significantly elevate antioxidant activity and reduce oxidative marker levels in patients who received moderate-to-high emetogenic potential chemotherapy compared to placebo.