Fig. 6

Bilobalide inhibited OA by activating the AMPK-SIRT1 pathway. A, B Immunofluorescence staining showed that bilobalide treatment increased the expression levels of phospho-AMPKα. C, D Immunofluorescence staining showed increased SIRT1 expression levels. E SIRT1 transcript levels were quantified using a real-time reverse transcription-polymerase chain reaction. F SIRT1 activity was quantified using a colorimetric measurement. G Western blot assays were used to determine the protein levels of P-AMPKα and SIRT1. The values represent the mean ± standard deviation. Each in vitro experiment was repeated three times or more. Statistically, significant differences between the indicated groups are indicated by ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, or ^****p < 0.0001