A Texas A&M AgriLife study with sheep may soon help address fertility problems in women, if it can discover ways to break the chain of generational transfer of polycystic ovary syndrome, PCOS — one of the most common infertility disorders.
Rodolfo Cardoso, DVM, Department of Animal Science assistant professor and reproductive physiologist in Texas A&M’s College of Agriculture and Life Sciences, will lead a $2.4 million National Institutes of Health-funded project that will investigate the multigenerational effects of prenatal exposure to androgen excess using the sheep as the animal model.
Joining Cardoso on this project are Renata Landers, a post-doctoral research associate in Cardoso’s program, Jessica Sustaita, a graduate student in Cardoso’s team, and Vasantha Padmanabhan, professor in the Department of Pediatrics with the University of Michigan Health System, who will also serve as a principal investigator in the project.
PCOS affects about 5 million women in the U.S. and over 100 million women worldwide. It is a complex syndrome that includes an increased risk of cardiovascular disease, dyslipidemia, hypertension, diabetes mellitus and endometrial cancer.
Findings from this sheep model will provide crucial biological information for improving reproductive function across generations and are of clinical relevance to women with PCOS and other hyperandrogenic fertility disorders.
Why sheep?
A critical concern of PCOS is the vertical transmission of unwanted traits to the offspring. A woman who has PCOS is highly likely to pass that to her daughters and granddaughters, Cardoso said. Sheep are very similar in that the daughters of ewes with PCOS also typically have the syndrome.
“The sheep is an animal model that is very translational to humans,” Cardoso explained. “When we look at what happens during fetal life, the development of the ovine fetus parallels that of humans. While much of biomedical work uses rodents in research, our ability to translate our findings are much easier and clinically relevant to humans when using sheep. Other key benefits are that sheep only generate one or two fetuses, not a litter, and they have a gestation process more similar to humans.”
Approximately 70% of women with PCOS are obese or overweight with metabolic complications, he said. It is well documented that if women are able to lose weight and improve metabolic function, they can improve their fertility. Also, it is known that whatever happens to a baby during fetal development can affect the health of that individual throughout life and can also carry over to the next generation upon reproduction.
Rodolfo Cardoso, DVM, checks for fertility in a sheep with a sonogram at the Texas A&M University Department of Animal Science Physiology Field Laboratory.