tea extracts protect against skin toxicity of radiation therapy

[Lani]

Tea Extracts Useful for Skin Toxicity From Radiotherapy
By Anthony J. Brown, MD

NEW YORK (Reuters Health) Dec 07 - Findings from a new study confirm that tea extracts applied topically promote the repair of skin damaged by radiotherapy, and shed light on the mechanisms involved. The beneficial effects of the extracts stem largely from an ability to attenuate proinflammatory signals.

Interrupting radiotherapy to address toxic skin effects can lead to inferior cancer outcomes, lead author Dr. Frank Pajonk, from the David Geffen School of Medicine at UCLA in Los Angeles, told Reuters Health. "So, it is important to have an effective treatment for this problem."

According to Dr. Pajonk, "tea extracts have been used as a folk remedy for sunburns, which led to their use as a treatment for radiation-induced skin toxicity. They have proven quite successful in this regard, but there was no scientific data" to clarify their effects.

In a study reported in the December 1st issue of BMC Medicine, the researchers analyzed the physiologic effects of green or black tea extracts in 60 patients with skin damage related to radiotherapy for head and neck cancers and those in the pelvic region.

Treatment with the tea extracts enhanced skin repair, the report indicates. For radiation damage in the head and neck region, the green and black tea extract were comparable in promoting repair, whereas in the pelvic region, green tea extract was superior, Dr. Pajonk said.

The tea extracts inhibited a key proteasome, known as 26S, which according to Dr. Pajonk "is at the center of the inflammatory machinery." This effect was associated with a reduction in several proinflammatory cytokines.

The researchers also found that the anti-inflammatory effects of the tea extracts did not stem solely from epigallocatechin-gallate, considered the most-active polyphenol of green tea.

Dr. Pajonk said that there is now a need for prospective studies comparing tea extract therapy with standard treatments for radiation-induced skin toxicity.

BMC Medicine 2006;4.