Effects of selenoprotein S on oxidative injury in human endothelial cells.
BACKGROUND
Selenoprotein S (SelS) is an important endoplasmic reticulum and plasma membrane-located selenoprotein implicated in inflammatory responses and insulin resistance. However, the effects of SelS on endothelial cells (ECs) have not been reported. In the present study, the role of SelS in oxidative stress and the underlying mechanism were investigated in human ECs.


METHODS
A SelS over-expression plasmid (pc-SelS) and a SelS-siRNA plasmid were transfected into human umbilical vein endothelial cells (American Type Culture Collection, USA). The cells were divided into four groups: control, SelS over-expression (transfected with pc-SelS), vector control, and SelS knockdown (transfected with siRNA-SelS). After treating the cells with H2O2, the effects of oxidative stress and the expression of caveolin-1 (Cav-1) and protein kinase Cα (PKCα) were investigated.


RESULTS
Following treatment with H2O2, over-expression of SelS significantly increased cell viability and superoxide dismutase (SOD) activity, and decreased malondialdehyde (MDA) production and Cav-1 gene and protein expression. However, no effects on PKCα were observed. In contrast, knockdown of SelS significantly decreased cell viability, SOD activity, and PKCα gene and protein expression, and increased MDA production and Cav-1 gene and protein expression.


CONCLUSIONS
SelS protects ECs from oxidative stress by inhibiting the expression of Cav-1 and PKCα.
Yin
Y
Zhao
Hua
H
Li
Li-li
LL
Men
Rong-chong
RC
Huang
Hai-cheng
HC
Zhou
Qian
Q
Xing
Jun-jie
JJ
Yao
Chun-hong
CH
Shi
Department of Endocrinology, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning, China. dujianling63@163.com.
Jian-ling
JL
Du
D001483:Base Sequence; D002478:Cells, Cultured; D017931:DNA Primers; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008315:Malondialdehyde / Q000378:metabolism; D008565:Membrane Proteins / Q000502:physiology*; D018384:Oxidative Stress / Q000502:physiology*; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051140:Selenoproteins / Q000502:physiology*; D013482:Superoxide Dismutase / Q000378:metabolism
D017931:DNA Primers; D008565:Membrane Proteins; C487710:SELENOS protein, human; D051140:Selenoproteins; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase