Effects of bee venom against Propionibacterium acnes-induced inflammation in human keratinocytes and monocytes.

Propionibacterium acnes (P. acnes) cause inflammatory acne and play an important role in the pathogenesis of acne by inducing inflammatory mediators. P. acnes contributes to the inflammatory responses of acne by activating inflammatory cells, keratinocytes and sebocytes to secrete pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-8. Bee venom has traditionally been used in the treatment of certain immune-related diseases. However, there has not yet been a robust trial to prove the therapeutic effect of bee venom in skin inflammation. The aim of the present study was to investigate anti-inflammatory properties of bee venom in skin inflammation induced by P. acnes using keratinocytes (HaCaT) and monocytes (THP-1). P. acnes is known to stimulate the production of pro-inflammatory cytokines such as IL-1, IL-8, IL-12 and TNF-α. In the present study, the production of interferon-γ (IFN-γ), IL-1β, IL-8 and TNF-α was increased by P. acnes treatment in HaCaT and THP-1 cells. By contrast, bee venom effectively inhibited the secretion of IFN-γ, IL-1β, IL-8 and TNF-α. Furthermore, P. acnes treatment activated the expression of IL-8 and toll-like receptor 2 (TLR2) in HaCaT cells. However, bee venom inhibited the expression of IL-8 and TLR2 in heat-killed P. acnes. Based on these results, it is concluded that bee venom has an effective anti-inflammatory activity against P. acnes in HaCaT and THP-1 cells. Therefore, we suggest that bee venom is an alternative treatment to antibiotic therapy of acne.