[Protective effect of baicalin against LPS-induced intestinal injury]

To investigate the protective effect of baicalin on the intestinal mucosal injury caused by endotoxin-lipopolysaccharide (LPS) and the anti-oxidative injury in colonic and ileal mucosa of rats with septicopyemia.

Fifty healthy male BALB/c mice were randomly divided into 5 groups: the normal control group, the model group, and baicalin high-dose, medium-dose and low-dose groups. They were orally administered with double distilled water, 100 mg x kg(-1) of baicalin, 50 mg x kg(-1) of baicalin, and 25 mg x kg(-1) of baicalin respectively for three days, once a day. 1 h after the oral administration on 3 d, they were intraperitoneally injected with normal saline or LPS (17 mg x kg(-1)). At 20 h after the injection of LPS, all of the mice were sacrificed, and their colonic and ileal tissues were collected. The mental status, life state and death rate of mice in each group were observed, and the lengths of colonic were measured. Chiu's scoring method was used to assess the intestinal mucosal injury. Histopathological changes of intestinal tissues were tested by HE staining. The ultraviolet spectrophotometry was used to detect total antioxidant capacity (T-AOC), superoxide dismutase (T-SOD), and glutathione peroxidase (GSH-PX) of intestinal homogenate. The immunohistochemical method was used to analyze the expression of PCNA in intestinal tissues of each group.

The death of mice was observed after the intraperitoneal injection of LPS. The death rates of baicalin groups were remarkably lower than the death rate of the model group. The colons in the medium-dose baicalin group were much longer than that in the model group (P < 0.05), with a much lower intestinal mucosa injury degree than the model group. Colonic and ileal injuries in the high-dose baicalin group significantly (P < 0.05). Colonic and ileal injuries in the medium-dose baicalin group and the low-dose baicalin group significantly reduced compare with the model group (P < 0.000 1). The medium-dose baicalin group showed no significant increase in homogenate's T-AOC, T-SOD and GSH-PX compare with the model group (P < 0.05). There was no significant difference between baicalin groups and the model group in PCNA.

Baicalin can protect intestinal epithelial cells suffering from injury from oxygen radicals, and relieve the intestinal injury caused by LPS by improving the intestinal mucosa structure and functions.