Written by Chrystal Moulton, Staff Writer. In a study on mice, researchers found that krill oil significantly slowed the development and progression of arthritis. Mice in the control group had a 42.9% incidence of arthritis, compared to only a 15.4% incidence in the krill oil group.
Rheumatoid arthritis is an autoimmune disease in which the body’s immune system attacks healthy tissue. (1) The exact cause of this disease remains unknown and about 1% of the individuals in industrialized societies suffer from this illness.(2) Drugs are usually prescribed to combat the degenerative effects of rheumatoid arthritis, however alternative therapeutic agents such as marine oils have shown promise in dealing with certain symptoms of the disease. Fish oils contain omega-3 fatty acids which have demonstrated positive effects on rheumatoid arthritis. (1-3) Krill oil, another kind of marine oil, is extracted from a very small crustacean called krill. Unlike other fish oils, krill oil is rich in antioxidants, phospholipids, and omega-3 fatty acids. Compared to standard fish oils, there is not as much research on the possible therapeutics effects of krill oil on rheumatoid arthritis.
In one study,(4) researchers compared the effects of krill oil and standard fish oil on collagen induced arthritis in mice. A total of 42 mice were evenly distributed into 3 groups: control group, fish oil group, and krill oil group. The diets for each group were specifically designed to contain similar amounts of total fatty acids. Furthermore, the diets for the mice in the fish oil group and the krill oil group were formulated to contain similar amounts of EPA and DHA (Total omega-3 content= Fish oil group: 0.78g/100g diet , Krill oil group: 0.81g/100g diet). All mice were supplemented with either the control, fish oil, or krill oil diet for 25 days. On day 25, arthritis was induced in all mice. On day 47, arthritis was induced in all mice once more to maintain the arthritic disease state. Arthritis assessment was done three times weekly on each mouse after induction of arthritis on day 47 and rated on a 4-point scale. At the end of the experiment on day 68, researchers also assessed tissue samples of the knee joints of each rat and drew blood samples to determine immune effects of fish oil and krill oil.
Researchers found that krill oil significantly slowed the development and progression of arthritis compared with controls and did so more significantly than standard fish oil. Arthritis was not observed in mice from the krill oil group until day 54. By that time, mice in the control group had a 42.9% incidence of arthritis with only 15.4% incidence in the krill oil group. Hind paw swelling was lower in the krill oil group compared to other groups, and significantly lower when compared to the control group. Furthermore, tissue samples of the knee joints revealed significant reduction in excessive cell growth in joint membrane and pro-inflammatory molecules in the krill oil group compared to the fish oil group. However, krill oil did not affect immune factors.
In all, krill oil may be a possible alternative therapy in treatment of rheumatoid arthritis. More studies are needed to confirm the effects krill oil demonstrated in the experiment.
Source: Ierna et al., Supplementation of diet with krill oil protects against experimental rheumatoid arthritis BMC Musculoskeletal Disorders 2010, 11:136
© 2010 Ierna et al; licensee BioMed Central Ltd. Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0)
Posted January 13, 2013.
Chrystal Moulton, BS, graduated from the University of Illinois at Chicago, where she received her degree in Psychology with a focus on pre-medical studies. She currently resides in Aurora, IL.
References:
- Rheumatoid Arthritis. PubMed Health.
- Accessed January 10, 2012.
- Rheumatoid arthritis. Scott DL, Wolfe F, Huizinga TW. Lancet. 2010 Sep 25;376(9746):1094-108.
- Omega-3 polyunsaturated fatty acids and inflammatory processes: Nutrition or pharmacology? Calder PC. Br J Clin Pharmacol. 2012 Jul 6. doi: 10.1111/j.1365-2125.2012.04374.x.
- Supplementation of diet with krill oil protects against experimental rheumatoid arthritis. Ierna M, Kerr A, Scales H, et al. BMC Musculoskelet Disord. 2010 Jun 29;11:136. doi: 10.1186/1471-2474-11-136.
