Beneficial effects of Houttuynia cordata polysaccharides on “two-hit” acute lung injury and endotoxic fever in rats associated with anti-complementary activities

Lu, Yan; Jiang, Yun; Ling, Lijun; Zhang, Yunyi; Li, Hong; Chen, Daofeng

The targets of CHCP in the complement activation cascade are indicated in Fig. 2 . The 1:8 NHS led to 96.7772.15% of hemolysis in the complement-control group. CHCP at the concentration of 1.4 mg/mL exhibited a strong inhibitory effect on the hemolysis (3.2970.67%). The hemolytic percentages induced by all the C-depleted sera were less than 10%, indicating that the C-depleted sera would not lyse erythrocyte independently. After treating with CHCP, the serum depleted of C1q still restored the hemolytic activity to 67.4074.79%, suggesting that CHCP did not block the complement cascade at C1q. C2-depleted and C9depleted sera also restored the hemolysis markedly (72.82710.61% for C2 and 63.2172.27% for C9). However, CHCP nearly abolished the hemolysis when C3-or C4-depleted serum was added (9.2971.69% for C3, 12.3471.39% for C4). For C5, the hemolysis was only partly restored (44.5473.92%). These results suggested that CHCP mainly block C3 and C4, and may interact with C5.