title: The Protective Effects of Isoliquiritigenin and Glycyrrhetinic Acid against Triptolide-Induced Oxidative Stress in HepG2 Cells Involve Nrf2 Activation.
abstract: Triptolide (TP), an active ingredient of Tripterygium wilfordii Hook f., possesses a wide range of biological activities. Oxidative stress likely plays a role in TP-induced hepatotoxicity. Isoliquiritigenin (ISL) and glycyrrhetinic acid (GA) are potent hepatoprotection agents. The aim of the present study was to investigate whether Nrf2 pathway is associated with the protective effects of ISL and GA against TP-induced oxidative stress or not. HepG2 cells were treated with TP (50 nM) for 24 h after pretreatment with ISL and GA (5, 10, and 20 μM) for 12 h and 24 h, respectively. The results demonstrated that TP treatment significantly increased ROS levels and decreased GSH levels. Both ISL and GA pretreatment decreased ROS and meanwhile enhanced intracellular GSH content. Additionally, TP treatment obviously decreased the protein expression of Nrf2 and its target genes including HO-1 and MRP2 except NQO1. Moreover, both ISL and GA displayed activities as inducers of Nrf2 and increased the expression of HO-1, NQO1, and MRP2. Taken together the current data confirmed that ISL and GA could activate the Nrf2 antioxidant response in HepG2 cells, increasing the expression of its target genes which may be partly associated with their protective effects in TP-induced oxidative stress.
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Ling-Juan
authors.initials: LJ
authors.lastname: Cao
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Huan-De
authors.initials: HD
authors.lastname: Li
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Yan
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Zhi-Hua
authors.initials: ZH
authors.lastname: Li
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Gong
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Jiang
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Ping-Fei
authors.initials: PF
authors.lastname: Fang
authors.affiliation: Department of Pharmacy, The Second Xiangya Hospital, Central South University, Changsha 410011, China; Institute of Clinical Pharmacy, Central South University, Changsha 410011, China; School of Pharmaceutical Sciences, Central South University, Changsha 410013, China.
authors.forename: Bi-Kui
authors.initials: BK
authors.lastname: Zhang