Who knew that male fertility depends on sperm-cell architecture? A University of Illinois study reports that a certain omega-3 fatty acid is necessary to construct the arch that turns a round, immature sperm cell into a pointy-headed super swimmer with an extra long tail.
Normal sperm cells contain an arc-like structure called the acrosome that is critical in fertilization because it houses, organizes, and concentrates a variety of enzymes that sperm use to penetrate an egg.
A new study shows for the first time that docosahexaenoic acid (DHA) is essential in fusing the building blocks of the acrosome together. Without DHA, this vital structure doesn't form and sperm cells don't work.
Men concerned about their fertility may wonder what foods contain DHA. Marine fish, such as salmon or tuna, are excellent sources of this omega-3 fatty acid. DHA is one of the two active components in fish oils supplements.
The scientists became intrigued with DHA's role in creating healthy sperm when they experimented with "knockout" mice that lack a gene essential to its synthesis. They looked at sperm count, shape, and motility, and tested the breeding success rate. The male mice that lacked DHA were basically infertile.
But when DHA was introduced into the mice's diet, fertility was completely restored. The study author said, The impact of DHA was very striking. “When we fed the mice DHA, all these abnormalities were prevented.”
The acrosome of a sperm cell is constructed when small vesicles containing enzymes fuse together in an arc. But that fusion did not happen without DHA.
In the absence of DHA, the vesicles are formed but they don't come together to make the arch that is so important in sperm cell structure.
The study author Nakamura finds the role this omega-3 fatty acid plays in membrane fusion particularly exciting. Because DHA is abundant in specific tissues, including the brain and the retina as well as the testes, the scientists believe their research findings could also impact research relating to brain function and vision.
"It's logical to hypothesize that DHA is involved in vesicle fusion elsewhere in the body, and because the brain contains so much of it, we wonder if deficiencies could play a role, for example, in the development of dementia. Any communication between neurons in the brain involves vesicle fusion," he noted.
University of Illinois College of Agricultural, Co. "Dietary DHA Linked To Male Fertility." Medical News Today. MediLexicon, Intl., 11 Jan. 2012. Web.
