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Calvin News

Calvin Prof Seeks Dry Eye Cure

Wed, Jul 12, 2000
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John Ubels, a Calvin College professor of biology, has earned a $375,000 research project grant from the National Eye Institute of the National Institutes of Health, the first-ever NIH grant of this type to be awarded to Calvin.

His work will be part of a larger effort that may someday lead to a cure for a debilitating diseases called "dry-eye syndrome," which is estimated to affect between 10 and 14 million people, most of them over the age of 40, in the U.S. alone. Many of these patients are post-menopausal women who have a condition known as Sjogren's Syndrome -- a combination of dry-eye and dry-mouth. In Sjogren's (SHOW GRINS) Syndrome the immune system attacks the lacrimal and salivary glands causing inflammation and decreased tear and saliva secretion.

Ubels' prestigious NIH research project grant is to study "The Role of Retinoids in Lacrimal Gland Function." For the next three years Ubels and a team of students will examine the relationships between Vitamin A (retinoids) and tear glands (lacrimal gland).

In addition to research supplies and equipment, the grant will fund two to three Calvin students a year to work on the project. Those students will get hands-on research experience; they also will be co-authors on presentations and publications in research journals. In fact, since Ubels returned to Calvin in 1995 (he is a 1974 graduate of Calvin), he has had 16 students work side-by-side with him on research projects. Those 16 students now are all in either graduate or medical school.

His next group of student researchers will assist him in an area of study he's pursued for 20 years. Ubels has been working with Vitamin A and the eye since 1980, during which time he has been funded by the NIH, while at major research universities. The new grant will allow him to continue his work on the relationship between Vitamin A and dry-eye syndrome.

In dry-eye syndrome the tear film that covers the eye is deficient or abnormal because of a malfunction of the tear glands. This leads to irritation, impaired vision, pain and disease of the cells on the ocular surface. In severe cases the eye is susceptible to infections and potential blindness. Presently there are no drugs available for treatment of dry-eye syndrome and only artificial tears are available for temporary relief of the symptoms of dry-eye.

"Dry-eye syndrome," says Ubels, "is a serious problem that doesn't get a lot of attention. There's no cure, just artificial tears which provide short-term relief. Working towards a solution for this problem will be satisfying for me and for my students."

In past years Ubels and other investigators have studied the use of Vitamin A ointment to treat dry-eye syndrome. "Although the treatment seemed logical," says Ubels, "it did not work well. It now appears that this was the result of interaction between Vitamin A and male sex hormones like testosterone, also known as androgens."

Work over the past decade has shown that androgens are required for normal tear gland function in both men and women. Androgens also appear to control function of the meibomian glands on the edges of the eyelids which produce oil that keeps tears from evaporating. Since women also produce androgens, and because androgen levels also drop after menopause, it has been proposed that lack of androgens is involved in the relatively high incidence of dry-eye in aging women.

Men on the other hand do not often have dry-eye because they produce androgens throughout life. Ubels notes that retinoids usually work against androgens. Examples of this action include such things as drugs like Retin-A and Accutane, which contain forms of Vitamin A and are used to treat acne, which is stimulated by androgens.

In fact, people who take Accutane often suffer from dry-eyes because the vitamin A in the medicine works not only against the androgens causing oily skin, but also the androgens which help tear glands lubricate the eye. For the next three years Ubels will work to understand the interactions between retinoids and androgens in the lacrimal gland at the cellular level. The results of this research, along with studies conducted by other investigators, may lead to a cure for millions of people suffering from dry-eye syndrome.

In November 2000, Ubels will be a keynote speaker at a major, international symposium on dry-eye syndrome. About 300 physicians and scientists from around the world will attend. Ubels has been asked to give a closing presentation that summarizes where research on dry-eye syndrome is now and where it should go in the future.

See the Grand Rapis Press
For more on Sjogren's Syndrome see