Fisetin

Catechin, quercetin, myricetin, fisetin, galangin, kaempferol, morin, trolox, bovine serum albumin (BSA), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,4,6-tri(2-pyridyl)-1,3,5-triazine (TPTZ) were all purchased from Tokyo Chemical Industry (Tokyo, Japan) with purity greater than 95%. Stock solutions were freshly prepared in methanol at a final concentration of 5.0 mmol L⁻¹ before the measurements. BSA stock solution (0.5 mmol L⁻¹) was prepared by dissolving the solid with double deionized water and stored at −20 °C. All the other reagents were analytic grade and double deionized water (18.25 MΩ·cm, 25 °C) from Millipore MilliQ system (Millipore Corporation, Milford, MA, USA) was used.

Eighteen-week-old MRL/lpr (n = 24) and MRL/MpJ mice (n = 24) were randomized for pharmacological treatment analysis, as previously described (25 (link)). Mice were orally administered 100 mg/kg fisetin (Tokyo Chemical Industry) (MRL/MpJ: n = 12 and MRL/lpr: n = 12) or vehicle (20% PEG 400) (MRL/MpJ: n = 12 and MRL/lpr: n = 12) five days a week for four weeks.

HaCaT cell line (human keratinocyte), obtained from Riken Bioresource Center (Tsukuba, Japan), was cultured in Dulbecco’s modified Eagle’s medium (Nissui, Tokyo, Japan) supplemented with 10% fetal bovine serum (Life Technologies, Gaithersburg, MD, USA) at 37 °C in a 5% CO₂ atmosphere. Human HFSCs were obtained from Celprogen (Torrance, CA, USA) and cultured in human hair follicle stem cell complete growth medium with serum (Celprogen) at 37 °C in a 5% CO₂ atmosphere. Fisetin (>96.0% purity; Tokyo Chemical Industry Co., Ltd., Tokyo, Japan) was purchased from

Ferulic acid (99%) was purchased from Sigma Aldrich (St. Louis, MO, USA). Ascorbic acid and quercetin (≤100%) were purchased from FUJIFILM Wako Pure Chemical Corporation (Osaka, Japan). Caffeic acid (≥98%), curcumin (100%), hesperidin (90%), rutin (95.0–101.5%), and triiodothyronine (T₃) were purchased from Nacalai Tesque, Inc. (Kyoto, Japan). Gallic acid (≥98%), chlorogenic acid (≥95%), ellagic acid (≥95%), sesamin (≥95%), epigallocatechin-3-gallate (≥96%), genistein (≥98%), daidzein (≥95%), luteolin (≥98%), theaflavin (≥98%), isoquercetin (98%), and morin (100%) were purchased from Cayman Chemical Company (Ann Arbor, MI, USA). Resveratrol (>99.0%), fisetin (>96.0%), isorhamnetin (>95.0%), and troxerutin (90%) were purchased from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan). Cyanidin chloride (99%) was purchased from Nagara Science Co. Ltd. (Gifu, Japan). Apigenin (≥98%) was purchased from LKT Laboratories, Inc. (St. Paul, MN, USA). Kaempferol (98%), myricetin (98%), and naringin (98%) were purchased from BDL Pharmatech Ltd. (Shanghai, China). Hyperoside (90–100%) was purchased from Toronto Research Chemicals Inc. (Toronto, ON, Canada). Neohesperidin (≥98%) was purchased from Chem-Impex International, Inc. (Wood Dale, IL, USA). All other chemicals were commercially available and had the highest possible purity.

Epigallocatechin, myricetin, fisetin, quercetin, kaempferol, galangin, naringenin, and Epigallocatechin gallate were purchased from the Tokyo Chemical Industry Co. (Tokyo, Japan). Lipofectamine 3000, CellROX Orange, and CellROX Deep Red were purchased from Thermo Fisher Scientific (Waltham, MA, USA), and the autophagy detection reagent, DALGreen, was purchased from Dojindo Laboratories (Kumamoto, Japan).

Eighteen-week–old MRL/MPJ mice (n = 24) and MRL/lpr mice (n = 24) were randomized for pharmacological treatment analysis. For oral administration, mice were gavaged with 100 mg/kg fisetin (Tokyo Chemical Industry, Tokyo, Japan) (MRL/MPJ: n = 12 and MRL/lpr: n = 12) or vehicle (20% PEG 400) (MRL/MPJ: n = 12 and MRL/lpr: n = 12) for 5 days every week for 4 weeks.