Fig. 4.
Effects of shikonin on LPS-induced TNF-α production and mRNA expression in BV2 microglial cells. Cells were seeded at a density of 2×105 cells/ml and were incubated with the indicated concentrations of shikonin 1 h before treatment with LPS (500 ng/ml). (A) After incubation for 24 h, the culture supernatants were collected, and the amount of TNF-α was measured by ELISA. (B) After treatment with LPS for 6 h, the level of TNF-α mRNA expression was determined by RT-PCR analysis. β-Actin was used as an internal control for RT-PCR. Each value indicates the mean ± S.E. and is representative of results obtained from three independent experiments. *p<0.05 denotes a significant difference from the value obtained from cells treated with LPS alone.