China: Study on 30% Supramolecular Salicylic Acid Peel

A recent study, based on analyses of the skin barrier and microbiota, has revealed that 30% supramolecular salicylic acid (SSA) peel has therapeutic effects in patients with moderate-to-severe acne vulgaris (AV). It is suggested that SSA exerts its effect by modulating the skin microbiome and improving the microenvironment, thus lessening local inflammation.

The findings published in the journal Dermatology and Therapy showed that 30% of SSA treatment affects species diversity and proportions; there was a significant decrease in Staphylococcus species and a decrease in Propionibacterium species. The researchers observed a substantial increase in Caveolin-1 expression and a reduction in the expression of toll-like receptor 2, transforming growth factor beta, and interleukin (IL)-1a, IL-17, and IL-6 in the skin tissue after treatment.

Thirty-per cent SSA is a modified salicylic acid preparation which is safe and effective for treating moderate-to-severe AV. However, there needs to be more clarity on its mechanism of action. Therefore, Xinyi Shao and colleagues from China aimed to assess the role of 30% SSA peels on skin inflammation and microbiota in patients with moderate-to-severe AV.

For this purpose, the researchers enrolled 28 patients and received biweekly 30% SSA peels for two months. They assessed the Global Acne Grading System (GAGS) score, transepidermal water loss (TEWL), skin water content, sebum levels, and pH. At the onset and two weeks after treatment completion, they obtained perilesional skin biopsies and microbial skin samples. A high-throughput sequencing approach was used to characterize the samples, targeting a portion of the bacterial 16S ribosomal RNA gene.

Study Findings

• After treatment, patients significantly improved their GAGS score and skin barrier indicators.
• There was a positive association of the GAGS score with the sebum concentration (R = 0.3) and pH (R = 0.39).
• The researchers observed an increased expression of caveolin-1 and reduced expression of transforming growth factor beta, interleukin (IL)-1a, IL-6, IL-17, and toll-like receptor two in the skin tissue after treatment.
• After treatment, the evenness and richness of the cutaneous microbiome decreased, and the proportion of Staphylococcus proportion decreased significantly, whereas the Propionibacterium proportion tended to decline.

"The findings showed that treatment with 30% SSA improved the GAGS score of moderate-to-severe acne patients," the researchers wrote in their study. "We speculated that SSA exerts its therapeutic effect by modulating the skin microbiome and improving the skin microenvironment, thereby improving local inflammation."

"Our results give a novel insight into the therapeutic rationale of treatment with 30% SSA treatment for moderate-to-severe AV," they concluded.

Reference

Shao, X., Chen, Y., Zhang, L. et al. Effect of 30% Supramolecular Salicylic Acid Peel on Skin Microbiota and Inflammation in Patients with Moderate-to-Severe Acne Vulgaris. Dermatol Ther (Heidelb) (2022). https://doi.org/10.1007/s13555-022-00844-5