Dr. Gasparro, an expert in photobiology, and author of the newly released book, Sunscreen Photobiology: Molecular, Cellular and Physiological Aspects, recognizes the new transgenic mouse line as one step in understanding that most sunscreens currently on the market are not completely protecting consumers' skin from sun damage.
"There is currently more sun exposure, skin cancer and, ironically, more sunscreen use than ever before," said Dr. Gasparro. "Sunscreens on the market certainly protect the skin from sunburn by absorbing UVB rays, but other forms of ultraviolet light like UVA, that can also contribute to skin aging and skin cancer, are not completely or only partially blocked by sunscreen. New vehicles for studying photoaging, like the transgenic mouse, can only lead us in the direction of more protective sunscreens."
In photoaged skin, the arrangement of normal elastin fibers is altered and transformed into large haphazard clumps, causing the skin's exterior to become leathery and wrinkled. Dr. Uitto developed and bred the transgenic mice. They microinjected fertilized mouse eggs with human elastin promoter linked to a chloramphenicol acetyltransferase (CAT) reporter gene, which indicates the rate of elastin promoter activation, or photodamage, triggered by exposure to ultraviolet light rays. Eric Bernstein, M.D., associate professor of dermatology and cutaneous biology at Jefferson, developed the use of the innovative transgenic mice as a model of photoaging.
"We wanted to develop a more rapid and sensitive means of studying
photoaging and compounds that might protect against sun damage in living
tissue," explained Dr. Uitto. "When we exposed the mice to controlled solar
simulating irradiation in the lab we learned from the CAT reporter gene that the
light acts as a
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Contact: Maria Cerceo or Phyllis Fisher
Maria.Cerceo@mail.tju.edu
215-955-6300
Thomas Jefferson University
17-Feb-1998