Icariin Regulates Acne Pathophysiology and Extracellular Matrix Protein Synthesis: Implications for Acne Vulgaris and Atrophic Acne Scar Management

Icariin, the principal active compound of Epimedium species used in traditional East Asian medicine, exhibits anti-inflammatory and lipid-regulating effects. However, its effects on human sebocytes and dermal fibroblasts, which could be implicated in the management of acne and atrophic scarring, remain unexplored. This study aimed to evaluate the effects of icariin on human sebocytes, keratinocytes and dermal fibroblasts. Icariin's effects on cell viability, lipid synthesis, inflammation, abnormal keratinization and extracellular matrix (ECM) synthesis were assessed using human SEB-1 sebocytes, HaCaT keratinocytes and Detroit 551 fibroblasts. Icariin modestly promoted the proliferation of SEB-1 sebocytes, HaCaT keratinocytes and Detroit 551 fibroblasts. It reduced mRNA levels of lipogenic and proinflammatory markers in SEB-1 sebocytes and HaCaT keratinocytes. Icariin counteracted arachidonic acid-induced lipogenesis in SEB-1 sebocytes in parallel with modulation of the insulin-like growth factor 1 receptor/Akt signalling pathway. In Detroit 551 fibroblasts, it enhanced ECM protein expression and reduced the expression of ECM-degrading enzymes, accompanied by upregulation of platelet-derived growth factor receptor and latent transforming growth factor β binding protein 4. In conclusion, this study demonstrates that icariin modulates key pathophysiological processes of acne and promotes ECM synthesis, suggesting its potential as a novel therapeutic agent for managing both acne and atrophic acne scars.