The aim of this study was to reveal the protection role and the related mechanism of
cytoglobin on the oxidation induced hepatic stellate cell damage. We applied
siRNA to interfere the endogenous
cytoglobin gene, used recombinant
cytoglobin protein to treat the completely activated human hepatic stellate cell line LX-2 and the incompletely activated primary rat hepatic stellate cells, or over-expressed
cytoglobin protein in LX-2 cells. We used two different oxidative-stress related models, the
hydrogen peroxide model and the
iron-overload model in our experiments and investigated the proliferation status and the intracellular
superoxide level of the cells. The results showed that endogenous
cytoglobin exerted significant protective effects on
hydrogen peroxide or
iron-overload induced LX-2 cell damage, confirming that upregulation of
cytoglobin was the protective response of activated hepatic stellate cells to oxidative stress. Recombinant
cytoglobin protein could protect LX-2 cells from oxidation induced damage, and prevent primary rat hepatic stellate cells from excessive proliferation and injury. The cytoplasmic
reactive oxygen species (ROS) scavenging capacity of the recombinant
cytoglobin protein was not as good as its capacity in scavenging ROS outside the cells, likely owing to the lack of active transporting mechanisms. Intracellular over-expression of
cytoglobin protein could exert significant protective effect on LX-2 cells treated with
hydrogen peroxide or
iron-overload. Our results would accelerate the exploitation of new anti-fibrotic targets.