Ginger constituents ameliorated B(α)P-induced toxicity via modulation of antioxidants and xenobiotic-metabolising enzymes in mice

Abstract

Accumulating evidence has linked benzo(α)pyrene (BαP) exposure to carcinogenesis with severe damages to reproductive, hematopoietic, hepatic, and renal tissues. Ginger (Zingiber officinale Roscoe) rhizome consumed worldwide as a spice and herbal medicine, exhibits a variety of health benefits including antioxidant, anti-inflammatory, and anti-cancer activities. In the present work, the efficacy of three ginger compounds namely 6-gingerol, zingerone, and curcumin against BαP-induced toxicity in mice was investigated. Kunming Swiss albino male mice were orally gavage with curcumin, 6-gingerol, or zingerone (all at a dose of 100 mg/kg body weight) for two weeks before intraperitoneal injection with benzo(α)pyrene (BαP) at 20 mg/kg body weight. The effect of these ginger compounds on antioxidant and xenobiotic-metabolising enzymes in vivo was investigated. Results showed that pre-treatment with curcumin, 6-gingerol, or zingerone significantly (p < 0.05) increased catalase (CAT) and glutathione peroxidase (GPx) activities in serum and liver of mice, upregulated activities of phase II enzymes (quinone reductase (QR) and glutathione-S-transferase (GST)), and their protein and mRNA levels in liver of mice; but reduced levels of activities, protein, and mRNA of phase I enzymes (CYP1A1 and CYP1A2) as compared to those of BαP-only treatment. Furthermore, these compounds significantly (p < 0.05) stimulated nuclear factor erythroid 2-related factor 2 (Nrf2) protein expression, whilst curcumin suppressed the expression of Kelch-like ECH-associated protein 1 (Keap1) in liver. These results could contribute to our understanding of the potential beneficial effects of consuming ginger as food and/or dietary supplement.