The therapeutic effect of tanshinone IIA on Propionibacterium acnes-induced inflammation in vitro

Acne vulgaris, a chronic inflammatory skin disease, affects many adolescents. New therapeutic agents for acne allow for a higher therapeutic activity, but fewer side effects. Tanshinone IIA, a natural product, has been proved to exhibit antibacterial and anti-inflammatory abilities in many diseases. However, its antibacterial and anti-inflammatory activities against Propionibacterium acnes have not been described. In the present study, the broth microdilution method was used to evaluate the antibacterial activity of tanshinone IIA and it had an inhibitory effect on the growth of P. acnes. Enzyme-linked immunosorbent assay and quantitative real-time PCR were used to investigate the effect of tanshinone IIA on IL-1β, IL-8, and TNF-α expression, and western blot was used to examine TLR2, NF-κB, and intercellular cell adhesion molecule-1 (ICAM-1) protein level induced by P. acnes in THP-1 cells. Results showed that the expression of inflammatory cytokines and TLR2, NF-κB, ICAM-1 protein levels were inhibited by Tanshinone IIA, suggesting that tanshinone IIA appeared to suppress P. acnes-induced inflammation by blockade of TLR2/NF-κB signaling pathway. In conclusion, the present study revealed the inhibitory effect of tanshinone IIA on P. acnes-induced inflammation, providing an evidence to support the mechanism of anti-acne properties of tanshinone IIA.