The Effect of Intense Pulsed Light on the Skin Microbiota and Epidermal Barrier in Patients with Mild to Moderate Acne Vulgaris

Background and Objectives The skin microbiota partly determined by epidermal barrier plays an important role in acne vulgaris and intense pulsed light (IPL) has been verified as a safe and effective therapeutic option for this disease. Nevertheless, the exact role of the IPL treatment on the skin microbiota and epidermal barrier for patients with acne vulgaris remains unclear. This article was designed to solve this problem. Study Design/Materials and Methods Nineteen healthy controls and 20 patients with mild to moderate acne were enrolled in this study, who received IPL treatment for 12 weeks. The epidermal barrier and skin samples were collected at baseline and after treatment. The microbial diversity was analyzed based on a high-throughput sequencing approach, which targets the V3-V4 region of the bacteria 16S ribosomal RNA genes. Results After treatment of IPL, the Global Acne Grading System (GAGS) scores, sebum, sclererythrin, and red area of patients were significantly improved by IPL treatment (P < 0.05). Although there was no difference in microbiota diversity before and after IPL treatment, the Nonmetric Multidimension Scaling (NMDS) analysis showed that the samples of the acne patients before and after treatment could be divided into two different sets by skin microbiota (P = 0.011), which could be verified by heatmap analysis. Moreover, we found that the relative abundance of Staphylococcus epidermidis (S. epidermidis) significantly increased, but Cutibacterium acnes (C. acnes) decreased after IPL treatment. The sebum concentration was positively correlated with PH value (R = 0.525, P = 0.017), and the GAGS was positively associated with both sclererythrin (R = 0.477, P = 0.002) and red area (R = -0.503, P = 0.001). Conclusions IPL could successfully improve the GAGS scores of acne vulgaris, as well as regulate the equilibrium between C. acnes and S. epidermidis, and inhibit the sebum secretion. Lasers Surg. Med. (c) 2021 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC.