Xyloketal B, a marine compound, acts on a network of molecular proteins and regulates the activity and expression of rat cytochrome P450 3a: a bioinformatic and animal study

Su, Junhui; Chang, Cui; Xiang, Qi; Zhou, Zhi-Wei; Luo, Rong; Yang, Lun; He, Zhi-Xu; Yang, Hongtu; Li, Jianan; Bei, Yu; Xu, Jinmei; Zhang, Minjing; Zhang, Qihao; Su, Zhijian; Huang, Yadong; Pang, Jiyan; Zhou, Shu-Feng

Rat liver microsomes were prepared as previously described. 29 Briefly, liver tissues were collected and washed with ice-cold KCl buffer (0.2 M, pH 7.4) until the tissues became pale or whitish, and then blotted dry and weighed. All subsequent steps were performed at 4°C. The liver samples were homogenized with three volumes of 0.05 M Tris⁄KCl buffer at pH 7.4 using a tissue homogenizer. The liver homogenates were then centrifuged at 9,000× g for 30 minutes. The supernatant was collected and centrifuged further at 105,000× g for 60 minutes. The supernatant was thereafter decanted and the microsomal pellets were resuspended in homogenization buffer and centrifuged again at 105,000× g for 60 minutes to remove the hemoglobin. Rat liver microsomes were resuspended in 0.1 M sodium phosphate buffer (0.8 mM ethylenediamine tetraacetic acid, 1 mM dithiothreitol, and 20% glycerol; pH 7.4) and stored at -80°C until analysis. The protein concentration of each microsomal sample was determined using the bicinchoninic acid protein assay (Pierce Chemicals, Rockford, IL, USA) with bovine serum albumin as the standard.