Phenolic compounds from Rosemary (Rosmarinus officinalis L.) attenuate oxidative stress and reduce blood cholesterol concentrations in diet-induced hypercholesterolemic rats

Background: Phenolic compounds combine antioxidant and hypocholesterolemic activities and, consequently, are expected to prevent or minimize cardiometabolic risk. Methods: To evaluate the effect of an aqueous extract (AQ) and non-esterified phenolic fraction (NEPF) from rosemary on oxidative stress in diet-induced hypercholesterolemia, 48 male 4-week old Wistar rats were divided into 6 groups: 1 chow diet group (C) and 5 hypercholesterolemic diet groups, with 1 receiving water (HC), 2 receiving AQ at concentrations of 7 and 140 mg/kg body weight (AQ70 and AQ140, respectively), and 2 receiving NEPF at concentrations of 7 and 14 mg/kg body weight (NEPF7 and NEPF14, respectively) by gavage for 4 weeks. Results: In vitro, both AQ and NEPF had remarkable antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH center dot) assay, which was similar to BHT. In vivo, the group that received AQ at 70 mg/kg body weight had lower serum total cholesterol (-39.8%), non-HDL-c (-44.4%) and thiobarbituric acid reactive substance (TBARS) levels (-37.7%) compared with the HC group. NEPF (7 and 14 mg/kg) reduced the tissue TBARS levels and increased the activity of tissular antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). Neither AQ nor NEPF was able to ameliorate the alterations in the hypercholesterolemic diet-induced fatty acid composition in the liver. Conclusions: These data suggest that phenolic compounds from rosemary ameliorate the antioxidant defense in different tissues and attenuate oxidative stress in diet-induced hypercholesterolemic rats, whereas the serum lipid profile was improved only in rats that received the aqueous extract.