title: Role of GPx4 in human vascular endothelial cells, and the compensatory activity of brown rice on GPx4 ablation condition.
abstract: Oxidative stress is implicated in the pathologies of vascular endothelial cells. However, the importance of specific antioxidant enzymes in vascular endothelial cells is not fully understood. The purpose of this study was to elucidate the importance of Glutathione peroxidase 4 (GPx4), and the involvement of ferroptosis on cell death induced by GPx4 loss in human vascular endothelial cells. In addition, we examined the compensatory activity of brown rice on GPx4 ablation condition. Human umbilical vein endothelial cells were transfected with GPx4 or scramble control siRNA. GPx4 knockdown caused the increase in the levels of lipid oxidation, and induced cytotoxicity. On the other hand, α-tocopherol (vitamin E) and extract of brown rice, ameliorated lipid peroxidation, cytotoxicity, and delay of proliferation induced by GPx4 knockdown. Furthermore, ferrostatin-1, inhibitor of ferroptosis, also prevented cytotoxicity and delay of proliferation. In conclusion, our data demonstrated that GPx4 is an essential antioxidant enzyme for protecting lipid peroxidation, and is a regulator of ferroptosis in vascular endothelial cells. Furthermore, vitamin E rich food, such as brown rice, can compensate for GPx4 loss by protecting cells against lipid peroxidation.
authors.affiliation: Senju Laboratory, Senju Pharmaceutical Co., Ltd., Kobe, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Sakai
authors.affiliation: Department of Food Science and Nutrition, Faculty of Agriculture, Kindai University, Nara, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Yasuzawa
authors.affiliation: Department of Applied Biological Chemistry, Graduate School of Agriculture, Kindai University, Nara, Japan.
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Sumikawa
authors.affiliation: Department of Ophthalmology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ueta
authors.affiliation: School of Pharmaceutical Sciences, Kitasato University, Tokyo, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Imai
authors.affiliation: Department of Applied Biological Chemistry, Graduate School of Agriculture, Kindai University, Nara, Japan.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Sawabe
authors.affiliation: Department of Food Science and Nutrition, Faculty of Agriculture, Kindai University, Nara, Japan; Department of Applied Biological Chemistry, Graduate School of Agriculture, Kindai University, Nara, Japan; Antiaging Centre, Kindai University, Higashi-osaka, Japan. Electronic address: sueshima@nara.kindai.ac.jp.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Ueshima
keywords: GPx4; Lipid peroxidation; Oxidative stress; Vascular endothelial cells; Vitamin E