EFFECTS OF BETA-CAROTENE AND ALPHA-TOCOPHEROL ON THE LEVELS OF TISSUECHOLESTEROL AND TRIGLYCERIDE IN HYPERCHOLESTEROLEMIC RABBITS

Male New Zealand white rabbits were made hypercholesterolemic by feedi ng an atherogenic diet (0.5% cholesterol, 3% peanut oil, and 3% coconu t oil) with and without beta-carotene (25 mg/kg body weight given intr avenously twice weekly) and/or alpha-tocopherol (0.5% of diet) for 8 w eeks. Rabbits treated with combined beta-carotene and alpha-tocopherol had significantly lower cholesterol contents in liver, heart, and pla sma than control animals; heart and plasma cholesterol contents were a lso significantly lower in animals treated with beta-carotene than in controls. Treatment with both antioxidants significantly increased tri glyceride contents of liver and triceps, but not heart and plasma. Rab bits given both beta-carotene and alpha-tocopherol had significantly l ower values for tissue alpha-tocopherol than animals treated with alph a-tocopherol only, and significantly higher values for tissue beta-car otene than animals treated with beta-carotene only. Atherosclerotic le sion areas in the aortic arch, thoracic aorta, and abdominal aorta wer e positively correlated (r = 0.36-0.42) with plasma cholesterol concen trations and negatively correlated (r = -0.34-0.60) with plasma, liver , triceps, and heart alpha-tocopherol levels. Moderate levels of alpha -tocopherol supplementation with or without beta-carotene may have a b eneficial effect on tissue cholesterol contents and on the development of aortic atherosclerotic lesions in rabbits fed an atherogenic diet. (J. Nutr. Biochem. 9:344-350, 1998) (C) Elsevier Science Inc. 1998.