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Leif S Jacobsson

Publications and source records attributed to Leif S Jacobsson.

2 recordsLinked to original sources
PubMed2004

Effects of alpha-tocopherol and astaxanthin on LDL oxidation and atherosclerosis in WHHL rabbits.

The aim of this study was to evaluate the influence of -tocopherol and astaxanthin on low-density lipoprotein (LDL) oxidation lag time and atherosclerotic lesion formation in Watanabe heritable hyperlipidemic (WHHL) rabbits. Thirty-one, 3-month-old WHHL rabbits were divided into three experimental groups. One group (n=10) was fed standard rabbit feed alone and served as a control, a second group (n=11) was supplied with the same feed containing 500 mg alpha-tocopherol/kg and a third group (n=10) was given a feed containing 100 mg astaxanthin/kg. Plasma lipids, lipoproteins and LDL oxidation lag time were followed for 24 weeks. At the end of the treatment period, the animals were killed and the thoracic aorta was used for evaluation of the degree of atherosclerosis. Colour photographs of the intimal surface of the vessel were taken for determination of the atherosclerotic area. Cross-sections of the thoracic aorta were used for histological examination and for determination of intimal thickening. Specimens of the vessel were used for determination of the tissue cholesterol content. Plasma cholesterol remained at a high level during the time of the experiment and there were no differences between the experimental groups. After 24 weeks, the LDL oxidation lag time was 53.7+/-1.7 min, 109+/-4 min (P<0.001) and 56.4+/-3.4 min (P=0.47) in the control, alpha-tocopherol and astaxanthin groups, respectively. In the thoracic aorta, the atherosclerotic area was 80.7+/-5.1%, 67.1+/-6.7% (P=0.13) and 75.2+/-5.7% (P=0.49) in the control, alpha-tocopherol and astaxanthin groups, respectively. The intimal thickening was 45.6+/-3.2%, 44.0+/-4.1% (P=0.89) and 40.0+/-4.5% (P=0.33) in the control, alpha-tocopherol and astaxanthin groups, respectively. Finally, the cholesterol content was 107+/-9 mol/g, 95.7+/-11.5 mol/g (P=0.31) and 101+/-5 mol/g (P=0.33) in the control, alpha-tocopherol and astaxanthin groups, respectively. It can be concluded that alpha-tocopherol but not astaxanthin prolonged the LDL oxidation lag time. The two antioxidative substances did not prevent atherogenesis in WHHL rabbits in this setting.

Animals↗
PubMed2004

Alpha-tocopherol and astaxanthin decrease macrophage infiltration, apoptosis and vulnerability in atheroma of hyperlipidaemic rabbits.

The composition of atherosclerotic plaques, not just macroscopical lesion size, has been implicated in their susceptibility to rupture and the risk of thrombus formation. By focusing on the quality of lipids, macrophages, apoptosis, collagen, metalloproteinase expression and plaque integrity, we evaluated the possible anti-atherosclerotic effect of the antioxidants alpha-tocopherol and astaxanthin in Watanabe heritable hyperlipidemic (WHHL) rabbits. Thirty-one WHHL rabbits were divided into three groups and were fed a standard diet, as controls (N =10), or a standard diet with the addition of 500 mg alpha-tocopherol per kg feed (N =11) or 100 mg astaxanthin per kg feed (N =10) for 24 weeks. We found that both antioxidants, particularly astaxanthin, significantly decreased macrophage infiltration in the plaques although they did not affect lipid accumulation. All lesions in the astaxanthin-treated rabbits were classified as early plaques according to the distribution of collagen and smooth muscle cells. Both antioxidants also improved plaque stability and significantly diminished apoptosis, which mainly occurred in macrophages, matrix metalloproteinase three expressions and plaque ruptures. Although neither antioxidant altered the positive correlations between the lesion size and lipid accumulation, the lesion size and apoptosis were only positively correlated in the control group. Astaxanthin and alpha-tocopherol may improve plaque stability by decreasing macrophage infiltration and apoptosis in this atherosclerotic setting. Apoptosis reduction by alpha-tocopherol and astaxanthin may be a new anti-atherogenic property of these antioxidants.

Animals↗