Effects of Hibiscus Sabdarrifa L. anthocyanins on cadmium-induced oxidative stress in Wistar rats
The search for potential ameliorative substances of Cadmium (Cd) toxicity is ongoing. Thus, this study was aimed at investigating the effects of Hibiscus Sabdarrifa L. anthocyanins (HSA) on Cd-induced oxidative stress in wistar rats. Anthocyanins were extracted from H. sabdariffa calyces using standard protocols and were identified with a Agilent HPLC system (model-LC 1100 series).Thirty wistar rats (185±5.2g) divided into Five (5) groups and were treated for fifteen days: Group 1: control, Group 2: Cd alone, 3mg/kg b wt, Group 3: HSA alone, 3mg/kg b wt, Group 4: HSA Pre-Cd - HSA (3g/ kg b wt for ten consecutive days) and Cd (3mg/ kg b wt) for the remaining five days, Group 5: HSA Post-Cd - Cd (3mg/kg b wt) for the first five consecutive days then HSA (3g/ kg b wt) for the remaining ten days. Comparison of HPLC chromatogram of anthocyanin extract of H. sabdariffa calyces with published data revealed the presence of malvidin-3-O-glucoside, delphinidin-3-monoglucoside, cyanidin-3-monoglucoside and petunidin-3-monoglucoside. Exposure to Cd significantly reduced (p<0.05) GSH levels and glutathione-s-transferase activity but significantly (P<0.05) increased lipid peroxidation in the plasma and tissues of rats. Cd-exposure also caused a significant decrease (p<0.05) in tissue SOD and CAT, but pre-treatment and post-treatment with HSA improved tissue SOD, CAT and GST activitieswith concomitant increase in GSH levels and reduction in tissue lipid peroxidation. This confirms the antioxidant capacity of H. sabdariffa anthocyanins in ameliorating Cd-induced oxidative stress when administered pre and post Cd exposure.
Keywords: Lipid Peroxidation, Catalase, Glutathione, antioxidants