Sperm ‘Switch’ Offers New Hope for Male Infertility

A new medical discovery is offering new hope for men suffering from infertility. Research published in the scholarly journal Science indicates that the ABHD2 protein molecule is in large part responsible for the mobility of sperm on their way to fertilize an egg. This protein can be referred to as the sperm ‘switch’ because of its ability to prevent conception when switched off and its key role in triggering motility in sperm when activated. ABHD2 could hold the key for new treatments for sluggish sperm, allowing men with fertility issues to increase their chances for successful conception. It may also provide an effective and reversible form of birth control for men. Dr. Parviz Kavoussi, an Austin male infertility specialist, offers some insights into this new research and what it means for those dealing with male fertility issues.


Advanced Research into Male Infertility

According to Dr. Kavoussi, male fertility depends on a few basic factors that include the following:

  • Sperm count
  • Morphology
  • Motility
  • Viability of sperm
  • Volume of semen

Previous medical research had indicated that calcium and progesterone were key factors in the ability of sperm to move effectively toward the Fallopian tubes to fertilize the egg. These substances were already known to interact with a protein called CatSper found in the flagellum, allowing this long tail to propel the sperm effectively. Researchers at the University of California, Berkeley, Yale University and the University of California, San Francisco engaged in a joint effort to determine if CatSper was the primary target of calcium and progesterone or if another intermediate step was involved in switching on the motility of male sperm. After repeated testing of various proteins, ABHD2 was identified as the intermediary to which progesterone binds, allowing the CatSper protein to generate motility in sperm cells.


How the Sperm ‘Switch’ Works

The mechanism that controls sperm motility was previously thought to involve the following sequence:

  • Calcium and progesterone trigger a reaction in CatSper that allows the flagellum to perform as required to propel the sperm into the Fallopian tubes to fertilize the egg.

Researchers have now demonstrated that the sequence actually involves an additional step:

  • Calcium and progesterone trigger a reaction in ABHD2, which serves as a catalyst for CatSper to trigger sperm motility.

If ABHD2 is not functional or present, the mobility of sperm will be significantly reduced. In this way, ABHD2 serves as a sperm switch that can have a real impact on male fertility.


Practical Applications for the Sperm ‘Switch’

The same process used to identify ABHD2 as a critical link in the sperm motility chain could also be used to treat male infertility. Dr. Kavoussi notes that the ABHD2-CatSper protein connection could provide added information for physicians who specialize in male fertility issues by demonstrating one additional element that must be present and functional for conception to occur. By addressing this factor and ensuring that ABHD2 is present and switched on, medical researchers may be able to develop positive treatments for male infertility to allow an increased chance of conception.