Researchers reported on continuing progress in the study of potential causes and other key aspects of rosacea during the National Rosacea Society's fourth annual research workshop, held in conjunction with the annual meeting of the Society for Investigative Dermatology.
More than 130 medical scientists learned about ongoing studies funded by the National Rosacea Society, as well as new approaches and technology to assess the severity of the disorder. The Society holds the workshop every year to foster interest in studying rosacea and to share findings uncovered by recent research.
"The Society's research grants program is producing ongoing improvements in our understanding of rosacea, and is now beginning to build off of earlier studies," said Dr. Jonathan Wilkin, chairman of the Society's medical advisory board. "This growing scientific knowledge of the disorder should ultimately provide a basis for advances in the effective care and treatment of patients with rosacea, as well as the potential for prevention or cure."
The Society's research grants program is funded by individual donations, and readers are encouraged to send tax-deductible contributions using the donation form inside. Dr. Richard Granstein, chairman of Dermatology at Cornell University, presented interim results of a study under way on how the common rosacea trigger factors of stress and ultraviolet light may lead to the telangiectasia (visible blood vessels) and inflammation (bumps and pimples) associated with rosacea.
Dr. Granstein noted that stress can lead to both physical and psychological effects by triggering the production of neuropeptides, substances produced by nerves or cells in the skin.
"Most neuropeptides cause dilation of the blood vessels and many common skin reactions like flushing and blushing -- common hallmarks of rosacea -- are linked to these substances," he said. "In addition, some neuropeptides are pro-inflammatory -- that is, they result in the recruitment of inflammatory cells, which produce bumps and pimples."
Preliminary research at Cornell showed that neuropeptides as well as ultraviolet B radiation, the type of sun radiation that causes sunburn and suntan, appear to induce the expression of vascular endothelial growth factor (VEGF). Previous research has found that VEGF is a regulator of blood vessel growth and may be involved in the formation of telangiectasia.1
Dr. Richard Burroughs, reporting on work undertaken with colleagues at the Walter Reed Army Medical Center and the University of Rochester, is investigating whether bacteria associated with the microscopic mite Demodex, a natural inhabitant of human skin, may be a possible cause of or contributor to the flushing and inflammation of rosacea.
Dr. Burroughs noted that in international studies of Demodex density, almost all showed significantly higher numbers of Demodex in rosacea patients than in individuals without rosacea. "This may mean that the Demodex itself plays a role, or perhaps that Demodex is associated with bacteria that cause dermatological problems," Dr. Burroughs said.
He noted that the presence of recently discovered bacteria, known as Wolbachia, has been found to increase the numbers of their host organism. If found in Demodex, Wolbachia may not only explain the greater density of Demodex in rosacea patients, he said, but may itself be a factor in the inflammation of rosacea. Dr. Burroughs' group is now testing biopsy samples from rosacea patients for the presence of these and other organisms in Demodex.
Kosmadaki M, Yaar M, Arble B, Gilchrest BA. UV induces VEGF through a TNF-alpha independent pathway. Federation of American Societies for Experimental Biology Journal. 2003;17:446-448.