Mice supplemented with astaxanthin (AstaReal 50F, BioReal) and were found to have accelerated body fat reduction or "fat-burning" when combined with exercise compared to just exercise alone, reports the study in the journal Biochemical & Biophysical Research Communications .
"Our present observations firstly demonstrated that astaxanthin could elevate fat utilization as energy substrate during exercise, at least partly, due to the antioxidant effect, which leading to improvement of endurance in prolong exercise and efficient reduction of adipose tissue with sustained exercise," wrote the researchers from Kyoto Prefectural University of Medicine, University of Shizuoka, University of Hyogo, and University of Nagoya report that.
The study adds to a small but growing body of research linking the carotenoid to potential weight management benefits.
Astaxanthin, the nutrient that gives salmon its pink colour, has been found to be a potent antioxidant, with tests suggesting that it may have a free radical fighting capacity worth 500 times that of vitamin E.
The carotenoid is produced by the Haematacoccus pluvialis algae when water supplies in its habitat dry up to protect itself against the effects of UV radiation.
Research has shown it to have a similar structure to lutein and zeaxanthin, but there are indications that it has an even stronger antioxidant activity.
Research on animals and some human clinical trials have suggested that the carotenoid may help protect against cataracts and UVA damage to the skin, as well as a number of other serious conditions such as stroke.
Annual growth of the global market for astaxanthin for human use is thought to be at least 15 per cent, with current estimates valuing the market at $15-20m (€12.4-16.6m) per year.
Lead researcher Wataru Aoi reports that the carotenoid appeared to protect the function of carnitine palmitoyl transferase I (CPT I) in mitochondria.
CPT I is a lipid transport enzyme found on the membrane of mitochondria and reportedly supplies lipids or "fuel" into the mitochondria for energy production.
The researchers divided mice into four groups: no exercise, no exercise plus with astaxanthin, exercise, and exercise plus astaxanthin.
After four weeks the animals in the exercise groups were placed on a treadmill to test a range of physical parameters.
Aoi and co-workers report that astaxanthin supplementation "accelerated the decrease of body fat accumulation with exercise training."
Moreover, the carotenoid was found to increase the co-localisation of fatty acid translocase with carnitine palmitoyltransferase I (CPT I) in skeletal muscle.
Fatty acid translocase is a glycoprotein found on the surface of the cell receives and transports long-chain fatty acids.
Finally, they also report that modifications of CPT I by hexanoyl-lysine, which occurred during exercise, where prevented by astaxanthin.
"Our results suggested that astaxanthin promoted lipid metabolism rather than glucose utilisation during exercise via CPT I activation, which led to improvement of endurance and efficient reduction of adipose tissue with training," concluded the researchers.
The study supports previous studies that show the carotenoid may have a role to play in the burgeoning weight management market.
With 50 per cent of Europeans and 62 per cent of Americans classed as overweight, the food industry is waking up to the potential of products for weight loss and management.
The category estimated to already be worth $7bn (€5.1bn).
Source: Biochemical & Biophysical Research Communications (Elsevier) 22 February 2008, Volume 366, Issue 4, Pages 892-897 "Astaxanthin improves muscle lipid metabolism in exercise via inhibitory effect of oxidative CPT I modification" Authors: W. Aoi, Y. Naito, Y. Takanami, T. Ishii, Y. Kawai, S. Akagiri, Y. Kato, T. Osawa, T. Yoshikawa