Mice face menopause for sake of womankind


By Andy Chang
Arizona Daily Wildcat
Tuesday, February 3, 2004

Even though Dr. Patricia Hoyer has been conducting research on mice at the UA for more than 15 years, she has a surprising claim: "If I saw a mouse in my kitchen, I would still run and scream."

But the same mouse that she would run away from could offer insight into menopause, if Hoyer pioneers a new procedure in which mice undergo menopause.

Hoyer has been studying menopause at the UA since 1989 and has been working on a new technique that better models how females progress into menopause using mice as test subjects.

"Many researchers just remove the ovary, when 94 percent of people go through natural menopause," said Hoyer. "Our model much more (closely) mimics the natural process."

The model Hoyer is working on can also study the stage leading up to menopause called perimenopause, an option not available with previous procedures.

"No other animal model can show perimenopause, which can last as long as 10 years," said Hoyer.

The basis of the research is a chemical called 4-vinylcyclohexene diepoxide or VCD. It is a chemical that females are naturally exposed to in specific workplaces.

"Manufacturing plants of synthetic rubber, tires or insecticides have been shown to expose women to VCD," said Hoyer. "It is not something you encounter naturally in everyday life, but in specific situations."

Though Hoyer's menopause mouse model has a variety of applicable uses, she hopes most to improve hormone replacement therapy in women.

"There are health risks associated with menopause and current hormone replacement therapy," said Hoyer. "This can lead to things like cardiovascular and bone disease. This research could improve hormone replacement therapy by designing specific chemicals that may protect (women) from these diseases."

The research can even be applied to animals to replace current sterilization techniques.

"This technique can be used for animals as a substitute for spaying and wildlife control," said Hoyer. "Injections or a pellet in a dart is a more natural and effective way."

Many industries are interested in Hoyer's research, and the university has obtained a patent to use VCD to cause menopause.

The effects of VCD research can impact the general public soon, but further research must first be completed.

"Realistically, it will take five to 10 years to see a beneficial, obvious direct effect," said Hoyer. "If a pharmaceutical company is interested, it can happen really fast."

There is also a personal motivation for Hoyer to be in charge of this type of research.

"Being a middle-aged woman myself is motivation for me to improve therapy and understand menopause," Hoyer said.