Vitamin C attenuates hemorrhagic shock induced dendritic cell accumulation and lung injury

Abstract

Objective To investigate the effect of hemorrhagic shock on dendritic cell accumulation in rat lung and lung injury, and to observe the protective effect of vitamin C. Methods Forty-two Sprague-Dawley rats (6 to 7 weeks old) were randomly divided into 7 groups (n=61 group): control group, hemorrhagic shock groups (HS 2 hours, HS 6 hours and HS 24 hours), and hemorrhagic shock+ vitamin C groups (HS+ VitC 2 hours, HS+ VitC 6 hours and HS+ VitC 24 hours). The rat hemorrhagic shock model was established by withdrawing blood through femoral arteriy. We used immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) technology to detect the expression level of dendritic cell specific intercellular adhesion molecule -3 (DC-SIGN) in rat lung tissues. The mRNA expression levels of TNF-α and IL-6, the myeloperioxidase activity in the lung tissues were tested, the lung injury scours were assessed simultaneously. Results There were few DC-SIGN proteins in rat lungs in control group. The expression levels of DC-SIGN protein increased markedly in hemorrhagic shock groups. The DC-SIGN mRNA concentration in rat lungs increased significantly 2 hours after hemorrhagic shock (P<0.05), and kept in high levels in 24 hours. The TNF-α and IL-6 mRNA concentration, the myeloperoxidase activity in lung tissues, and the histological damage scores of lungs were all increased in hemorrhagic shock groups compared with control group (P<0.05). All these phenomena induced by hemorrhagic shock were relieved when vitamin C was treated before resuscitation (P<0.05). Conclusions Perhaps hemorrhagic shock induced acute lung injury by promoting dendritic cell accumulation in rat lungs.Vitamin C curbed this phenomenon. Key words: Shock, Hemorrhagic; Dendritic cells; Acute lung injury