The February 2010 issue of the Journal of Lipid Research published the results of study at the University of Illinois which is the first to demonstrate a direct role for the omega-3 fatty acid docosahexaenoic acid (DHA) in sperm formation.
University of Illinois at Champaign researcher Dr. Manabu T. Nakamura and associates used genetically modified mice that cannot produce certain crucial fatty acids required to produce sperm, including DHA. These animals cannot form sperm and are infertile. The genetically modified mice and normal mice were given diets supplemented with arachidonic acid or DHA from weaning until 16 weeks of age.
Those animals receiving DHA had a breeding success equal to normal mice, and showed normal sperm count and formation, as opposed to those that did not receive DHA.
DHA restored all reproduction impairment in the supplemented mice.
"In our experiment, we used 'knockout' mice that lacked the gene responsible for an enzyme important in making docosahexaenoic acid,” explained Dr Nakamura. “In the absence of DHA, male mice are basically infertile, producing few if any misshaped sperm that can't get where they need to go."
"We looked at sperm count, shape, and motility and tested the breeding success rate, and the mice lacking DHA simply were not able to breed," lead author Manuel Roqueta-Rivera noted. “It was very striking. When we fed the mice DHA, all these abnormalities were prevented."
In the future, the researchers will continue to investigate DHA’s impact on male fertility. "We get hints from looking at sperm in the DHA-deficient animals about what type of pathology we may be looking at and why these polyunsaturated fatty acids are important,” Dr Nakamura said. “But we're still at the starting point in understanding the mechanisms that are involved and we need to do more research at the cellular level."