Efficacy of 1% 4-ethoxybenzaldehyde in reducing facial erythema.

BACKGROUND: Facial erythema is a common postsurgical and dermatologic problem. It is commonly the result of dermal inflammation arising from either a facial surgical procedure, such as laser resurfacing, dermabrasion, or a face peel, or from an underlying dermatologic condition, such as rosacea. Facial erythema is difficult for the dermatologist to treat in both settings because topical corticosteroids cannot be used long term on the thin facial skin and anti-inflammatory oral or topical antibiotics have associated side effects. OBJECTIVE: The goal of this pilot study was to evaluate the anti-inflammatory effect of 1% 4-ethoxybenzaldehyde in a rosacea model of facial erythema. METHODS: Thirty subjects with mild to moderate stable rosacea were enrolled in this 4-week, double-blind, vehicle-controlled study. Photographs, investigator assessment, and subject assessment were the efficacy criteria. RESULTS: There was a statistically significant reduction in facial erythema (p<.01) in those subjects who used the active for 4 weeks, as well as a statistically significant improvement in uneven skin tone (p<.01) and the overall severity of the disease (p<.01). There was no statistically significant difference in any of these three indices in the vehicle-treated group. CONCLUSION: The results suggest that benzaldehyde-derived anti-inflammatory agents may be useful in reducing facial erythema in a rosacea model.

The relationship between Na(+)/H(+) exchanger expression and tyrosinase activity in human melanocytes.

The activity of melanosome-associated tyrosinase in human melanocytes differs based on racial skin type. In melanocytes from Black skin, tyrosinase activity is high while in White melanocytes the activity of the enzyme is low. Recent studies suggest that low tyrosinase activity in White melanocytes may be due to an acidic pH environment within the melanosome. Because sodium/hydrogen (Na(+)/H(+)) exchangers (NHEs) are known to regulate intracellular pH, melanocytes were treated with NHE inhibitors to determine what effect this inhibition might have on tyrosinase activity. Treatment of Black melanocytes with ethyl-isopropyl amiloride (EIPA) caused a rapid dose-dependent inhibition of tyrosinase activity. This inhibition was not due to either direct enzyme inhibition or to a decrease in tyrosinase abundance. In contrast, treatment of White melanocytes with EIPA, cimetidine, or clonidine resulted in little inhibition of tyrosinase activity. Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis showed that both Black and White melanocytes expressed mRNA and protein for NHE-1, NHE-3, NHE-5, NHE-6, and NHE-7. Immunohistochemical analysis showed that NHE-7 and NHE-3 co-localized with the melanosomal protein, Tyrosinase Related Protein-1 (TRP-1). In addition, the vesicular proton pump, vesicular ATPase (V-ATPase), was found to be present in both White and Black melanosomes, indicating that organelles from both racial skin types are capable of being acidified. The results suggest that one or more NHEs may help regulate melanosome pH and tyrosinase activity in human melanocytes.