Mitochondrial Activity Measurement of Human Follicle Dermal Papilla Cells

Human follicle dermal papilla (HFDP) cells were purchased from PromoCell (cat# C-12072; Heidelberg, Germany) and cultured in follicular dermal papilla cell growth medium (C-26051; PromoCell) according to the manufacturer’s protocol at 37°C in a humidified atmosphere of 5% CO₂. The rat basophilic leukemia mast cell line RBL-2H3 cells were purchased from American Type Culture Collection (ATCC, VA, USA). RBL-2H3 cells were cultured in DMEM supplemented with 10% heat-inactivated fetal bovine serum (FBS, WELGENE) and 1% penicillin and streptomycin at 37°C in a humidified atmosphere of 5% CO₂. DHT and Compound 48/80 were purchased from Sigma-Aldrich (St. Louis, MO, USA). To measure the mitochondrial activity of HFDP cells, cells were cultured in 96-well plates and treated with WEML. After 24 h, 20 μL MTS solution (Promega, Madison, WI, USA) was added and cells were incubated at 37°C for 1 h (Kim et al. 2020 (link)). Absorbance was measured at 490 nm using a microplate reader (ABS Plus; Molecular Devices, San Jose, CA, USA). Mitochondrial activity was measured using the following equation:
$\mathrm{M}\mathrm{i}\mathrm{t}\mathrm{o}\mathrm{c}\mathrm{h}\mathrm{o}\mathrm{n}\mathrm{d}\mathrm{r}\mathrm{i}\mathrm{a}\mathrm{l}\mathrm{a}\mathrm{c}\mathrm{t}\mathrm{i}\mathrm{v}\mathrm{i}\mathrm{t}\mathrm{y}\left(\text{\%}\right)=({\displaystyle \frac{A_{\mathrm{e}\mathrm{x}\mathrm{p}\mathrm{e}\mathrm{r}\mathrm{i}\mathrm{m}\mathrm{e}\mathrm{n}\mathrm{t}\mathrm{a}\mathrm{l}\mathrm{g}\mathrm{r}\mathrm{o}\mathrm{u}\mathrm{p}}-A_{\mathrm{s}\mathrm{a}\mathrm{m}\mathrm{p}\mathrm{l}\mathrm{e}\mathrm{b}\mathrm{l}\mathrm{a}\mathrm{n}\mathrm{k}}}{A_{\mathrm{c}\mathrm{o}\mathrm{n}\mathrm{t}\mathrm{r}\mathrm{o}\mathrm{l}\mathrm{g}\mathrm{r}\mathrm{o}\mathrm{u}\mathrm{p}}})\times 100}$ where A is the absorbance for the given wavelength.