Effect Of Shenqi Fuzheng Injection On Expression Of Fractalkine In Lipopolysaccharide-induced Acute Lung Injury

Objective To investigate the expression of Fractalkine(FKN) in lipopolysaccharide(LPS)-induced acute lung injury(ALI) and effect by dexamethasone or Shenqi Fuzheng Injection. Methods A rat model of ALI was established by injection of LPS with a dose of 0.4mg/kg. Sixty Wistar rats were randomly divided into the normal group and three LPS plus Saline(LPS+NS),LPS plus dexamethasone(LPS+DEX) or LPS plus Shengqi Fuzheng Injection(LPS+SQ) pre-treated groups at different intervals(lh,2h 4h),6 rats each group. Using the methods of ELISA and RT-PCR, we examined the following parameters in the whole stage of the modles: pathologic alteration of lung, wet and dry ratio (W/D) of lung, proinflammatory cytokines TNF- and the expression level of FKN mRNA in lung tissue. We also observed the effects of dexamethasone or Shenqi Fuzheng Injection on the aboved-mentioned parameters. Result 1. In all LPS+NS groups, the pathologic manifestation of lung was significantly altered, especially in 2h group. Dexamethasone or Shenqi Fuzheng Iniection could lighten the alteration. 2. In all LPS+NS groups, the W/D was significantly increased, Dexamethasone or Shenqi Fuzheng Injection might reduce theincrease of W/D. 3. In all LPS+NS groups, TNF- a level was significantly increased. The level of TNF- a peaked at 2h after LPS injection. Dexamethasone or Shenqi Fuzheng Injection could decrease the peak concentration of TNF- α . 4. It was detected the expression of FKN mRNA in the normal lung tissue. In all LPS+NS groups, the level of FKN mRNA expression in the lung tissue was significantly increased, especially at 2h, which was quite different from the normal controls (p<0.05). Dexamethasone or Shenqi Fuzheng Injection might prevent the increase. The level of FKN mRNA expression in the lung tissue positively correlated with the concentration of TNF- α . Conclusions After LPS injection, the increase of TNF- α level and the increase of the level of FKN mRNA expression in the lung tissue resulted in a series of pathophysiologic alteration ,which might aggravate lung injury. This process might be an important link in the pathogenetic mechanism of ALI by LPS. This study also suggests that pre-treated with Dexamethasone or Shenqi Fuzheng Injection can inhibit the increasing of TNF- α in plasma and prevent the increase of the expression of FKN mRNA. It may be one of mechanisms in Dexamethasone or Shenqi Fuzheng Injection against LPS-induced lung injury.