Study named a “top discovery” in endocrinology
By Sarah Carey
An article coauthored by two scientists at the University of Florida College of Veterinary Medicine was recently selected as one of 2016’s top endocrine discoveries by editors of two leading professional journals in that field.
Paul Cooke, Ph.D., a professor of physiological sciences, and his postdoctoral associate, Manjunatha Nanjappa, spearheaded the study, titled “Membrane-associated estrogen receptor in the male reproductive tract,” which appeared in the journal Endocrinology last summer. The study provides new insight into the way in which estrogen, a hormone traditionally associated with women, is involved in male reproductive health.
Building on previous research, including a key study published in Nature almost 20 years ago that established estrogen plays an essential role in male reproduction by controlling fluid resorption in the testes and influencing the fertilization capacity of spermatozoa, the authors focused on one of the molecular pathways believed to affect how estrogen acts in the body.
The authors were able to show that mice genetically altered to lack a particular cell membrane estrogen receptor known to partially mediate the effects of estrogen had extensive reproductive abnormalities compared to their normal counterparts.
Mice without the membrane estrogen receptor showed significantly reduced sperm motility, and decreased sperm viability. These mice also displayed testicular abnormalities, and became infertile with advancing age.
The findings identify a previously unknown role for the membrane estrogen receptor in the development of normal sperm and providing an adequate environment for spermatogenesis, the paper reports.
The results could mean that new therapeutic tools might be on the horizon, taking advantage of “a previously underappreciated pathway,” according to an article by Melissa Mapes in Endocrine News, a publication of the national Endocrine Society. Mapes’ article lists the UF paper as one of its 2016 “Top Endocrine Discoveries” selected by five editors from the journals Endocrinology and The Journal of Clinical Endocrinology.
The possibilities of the research are far-reaching, and may even include a male contraceptive approach, the story states, adding that further research will determine the clinical potential of tapping into these rapid signaling pathways in the male reproductive tract.
Nanjappa presented the findings at the national meeting of the American Society of Andrology in New Orleans in April 2016. He received a Trainee Merit Award and a Larry Ewing Memorial Trainee Travel Award to attend.
“The role of estrogen in male reproductive health and particularly membrane-initiated pathways is a very hot topic right now,” Nanjappa said. “It’s important to understand how the estrogen receptors operate, and our research partially explains this link mechanistically — how estrogen signaling works in males as well as in females.”
Coauthors who contributed to the research include Rex Hess, Ph.D., University of Illinois, Urbana-Champagne; Ellis R. Levin, M.D., University of California, Irvine; Seth Locker and Theresa Medrano, University of Florida.