If the results of the study, published in the journal Nutrition , can be repeated in humans, they will add to a significant body of research supporting the potential heart health benefits of lycopene, predominantly associated with benefits for prostate health.
Lycopene is an antioxidant that is present in red- and pink-coloured fruits and vegetables.
As well as being used as a food colouring, it is also used in supplements.
The role of lycopene in heart health and in reducing the risk of certain cancers is supported by a body of research.
Min-Yu Hu and co-workers from the Central South University in Changsha, China divided 40 male adult rabbits into five equal groups to consume a standard diet, a high-fat diet, a high-fat diet plus 4 or 12mg per kg of lycopene, or the high-fat diet plus 10mg per kg of fluvastatin.
The animals consumed the diets for eight weeks.
The researchers used a relatively high dose of lycopene (4 and 12 mg/kg of body weight) because rabbits reportedly do not absorb the nutrient efficiently.
These doses produced blood levels of the carotenoid of 0.19 and 0.24 moles per litre, respectively. "
This corresponds to low plasma levels of lycopene in humans who may achieve five-fold higher levels already with the intake of only 0.3 mg/kg of body weight," explained the authors.
At the end of the study, the animals fed only the high-fat diet had higher levels of total and LDL cholesterol, triacylglycerols, oxidised low-density lipoprotein, malonaldehyde, and interleukin-1 than animals fed the standard diet.
However, animals fed the high-fat diet and supplemented with lycopene or fluvastatin had improved levels of these biomarkers, and the lycopene of both doses was better than the statin. "
The results of our experiment in the high-fat diet rabbit model showed that lycopene and fluvastatin lowered serum levels of total cholesterol and LDL-cholesterol, improved lipid metabolism, and reduced the amount of triacylglycerols," wrote the authors.
" Lycopene intervention reduced the increase in ox-LDL levels in rabbits on the high-fat diet, whereas fluvastatin did not show such an effect.
The cause of this difference is at present not known, although the result speaks in favour of lycopene," they added.
" These findings provide a theoretical rationale for the use of lycopene as a preventive in atherosclerosis," they concluded.
Atherosclerosis, or hardening of the arteries, is a major risk factor for cardiovascular disease (CVD), which causes almost 50 per cent of deaths in Europe, and is reported to cost the EU economy about €169bn ($202bn) per year.
Source: Nutrition Published online ahead of print, 30 June 2008, doi: 10.1016/j.nut.2008.05.006 " Comparison of lycopene and fluvastatin effects on atherosclerosis induced by a high-fat diet in rabbits" Authors: M.-Y. Hu, Y.-L. Li, C.-H. Jiang, Z.-Q. Liu, S.-L. Qu, Y.-M. Huang