Hplc solvents

CoQ₁₀ powder, PureSorb-QTM^TM40 (P40), which is containing 40 w/v% CoQ₁₀, was kindly donated by Nisshin Pharma Inc. (Tokyo, Japan) for this study.^{(13 (link))} High performance liquid chromatography (HPLC) solvents and ethanol were purchased (HPLC grade) from Wako Pure Chemical Industries, Ltd. (Osaka, Japan). All other chemicals used were of analytical grade, available from commercial suppliers. Antibodies against type I collagen was obtained from COSMO BIO Co., Ltd. (Tokyo, Japan). Normal human dermal fibroblast (NHDF) was purchased from Lonza Co. Ltd. (Tokyo, Japan). Fibroblasts were grown in Dulbecco’s modified Eagle’s medium (DMEM; Nacalai Tesque, Kyoto, Japan) supplemented with 2% fetal bovine serum (FBS; MP Biomedicals, Illkirch, France), 2 mM glutamine, 100 units/ml penicillin and 100 mg/ml streptomycin (Nacalai Tesque). The cells were incubated under 37°C in a humidified atmosphere of 5% CO₂ and 95% air in a CO₂ incubator. After 24 h, culture medium was replaced by the DMEM containing 2% FBS and P40, and the cells were subsequently pre-cultured for 1 week in the CO₂ incubator for all experiments in this study.