title: Saikosaponin-D attenuates heat stress-induced oxidative damage in LLC-PK1 cells by increasing the expression of anti-oxidant enzymes and HSP72.
abstract: Heat stress stimulates the production of reactive oxygen species (ROS), which cause oxidative damage in the kidney. This study clarifies the mechanism by which saikosaponin-d (SSd), which is extracted from the roots of Bupleurum falcatum L, protects heat-stressed pig kidney proximal tubular (LLC-PK1) cells against oxidative damage. SSd alone is not cytotoxic at concentrations of 1 or 3 μg/mL as demonstrated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. To assess the effects of SSd on heat stress-induced cellular damage, LLC-PK1 cells were pretreated with various concentrations of SSd, heat stressed at 42°C for 1 h, and then returned to 37°C for 9 h. DNA ladder and MTT assays demonstrated that SSd helped to prevent heat stress-induced cellular damage when compared to untreated cells. Additionally, pretreatment with SSd increased the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) but decreased the concentration of malondialdehyde (MDA) in a dose-dependent manner when compared to controls. Furthermore, real-time PCR and Western blot analysis demonstrated that SSd significantly increased the expression of copper and zinc superoxide dismutase (SOD-1), CAT, GPx-1 and heat shock protein 72 (HSP72) at both the mRNA and protein levels. In conclusion, these results are the first to demonstrate that SSd ameliorates heat stress-induced oxidative damage by modulating the activity of anti-oxidant enzymes and HSP72 in LLC-PK1 cells.
authors.affiliation: College of Animal Science and Veterinary Medicine, Qingdao Agricultural University, Qingdao 266109, Shandong Province, China.
authors.forename: Bao-Zhen
authors.initials: BZ
authors.lastname: Zhang
authors.forename: Xiao-Tong
authors.initials: XT
authors.lastname: Guo
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Chen
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Xia
authors.initials: X
authors.lastname: Cong
authors.forename: Zhong-Ling
authors.initials: ZL
authors.lastname: Jiang
authors.forename: Rong-Feng
authors.initials: RF
authors.lastname: Cao
authors.forename: Kai
authors.initials: K
authors.lastname: Cui
authors.forename: Shan-Song
authors.initials: SS
authors.lastname: Gao
authors.forename: Wen-Ru
authors.initials: WR
authors.lastname: Tian
mesh_terms: D000818:Animals; D029972:Bupleurum / Q000737:chemistry; D002374:Catalase / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005979:Glutathione Peroxidase / Q000378:metabolism*; D050884:HSP72 Heat-Shock Proteins / Q000378:metabolism*; D018869:Heat-Shock Response / Q000187:drug effects*; D006358:Hot Temperature / Q000009:adverse effects*; D018374:LLC-PK1 Cells; D008315:Malondialdehyde / Q000378:metabolism; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012503:Saponins / Q000737:chemistry / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000378:metabolism*; D013552:Swine
chemical_list: C051274:Bupleurum root extract; D050884:HSP72 Heat-Shock Proteins; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012503:Saponins; D008315:Malondialdehyde; D009828:Oleanolic Acid; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; C025759:saikosaponin D
keywords: Anti-Oxidant Enzymes; HSP72; Heat Stress; LLC-PK1; Saikosaponin-d