Attenuating effect of pretreatment with Yiqifumai on lipopolysaccharide-induced intestine injury and survival rate in rat

BACKGROUND: Yiqifumai is a traditional Chinese medicine compound preparation used for treatment of microcirculatory disturbance-related diseases in China. We have previous reported that pretreatment with Yiqifumai could improve the lipopolysaccharide (LPS) -induced microcirculatory disturbance in rat mesentery. The present study intended to investigate the effect of pretreatment with Yiqifumai on intestine injury and survival rate of the rats subjected to LPS challenge. METHODS: Male Wistar rats were continuously infused with LPS (5 mg kg(-1 )body weight h(-1)) via the left jugular vein for 90 min. In some rats, Yiqifumai 80 (mg/kg) was administrated through the left jugular vein 10 min before LPS infusion. The mean arterial pressure (MAP), heart rate (HR), rectal temperature (RT), respiratory rate (RR) and survival rate were measured at 24 h, 48 h and 72 h after LPS infusion. At 72 h after exposure to LPS, the intestine morphology was observed under a stereomicroscope and the immunohistochemistry staining of intestine was conducted to evaluate the expression of intercellular adhesion molecule 1 (ICAM-1) and the number of myeloperoxidase (MPO) positive cells in tissue. After observation of intestine microcirculation, blood was collected from the abdominal aorta of each animal to analyze the level of inflammatory markers in plasma, including TNF-α and MCP-1. RESULTS: Compared to the control, LPS infusion significantly decreased MAP and the survival rate and increased the HR, RT and RR, as well as elicited leukocyte infiltration, intestine hemorrhage, enhanced expression of ICAM-1 and raised level of inflammatory markers. All of indicators, except for the RT, were significantly attenuated by Yiqifumai, in contrast to the LPS group. CONCLUSIONS: The results demonstrated the potential of pretreatment with Yiqifumai to ameliorate rat intestine injury, inflammatory response to LPS and the decrease in survival rate caused by LPS challenge.