Effects of beta-D-glucan on steroid-induced impairment of colonic anastomotic healing.

BACKGROUNDS/AIMS: Inflammation during the early phase of anastomotic wound healing is an essential cellular response and is suppressed by corticosteroids. The anti-inflammatory effect of corticosteroids is largely responsible for its impairment of wound healing in bowel anastomosis. Beta-D-glucan, a commonly used macrophage activator, has been shown to improve anastomotic wound healing under normal conditions. In the present study, we have investigated the effects of beta-D-glucan on anastomotic wound healing in rats treated with long-term corticosteroid.

METHODOLOGY: 92 male Sprague-Dawley rats were randomized into four groups. 1 : control, 2: control + beta-D-glucan, 3 : steroid, 4 : steroid + beta-D-glucan. Methylprednisolone (5mg/kg) was injected IM daily for 14 days in groups 3 and 4. After 14 days, following anaesthesia and laparotomy, colonic anastomosis was performed 3 cm away from the peritoneal reflection of rectum. In groups 2 and 4, 100mg/kg beta-D-glucan was administered orally for 7 days before laparotomy. On postoperative day 3, relaparotomies were performed and bursting pressures, hydroxyproline levels and histopathological specimens were studied.

RESULTS

The mean values of bursting pressures groups were 50.8 (95% CI 46.99-56.50), 58.2 (95% CI 54.49-61.90), 32.0 (95% CI 29.21-34.98), 45.9 (95% CI 43.09-48.80) respectively. The differences of the mean values of the groups between group 1 and 2 and also 3 were significant (p = 0.002, p < 0.001). The mean values of hydroxyproline of the groups were 3.8 (95% CI 3.56-4.06), 4.7 (95% CI 4.50-5.04), 2.9 (95% CI 2.73-3.20), 3.9 (95% CI 3.65-4.22) respectively. The differences of the values of the groups between control (group1) and group 2 and also group 3 were significant (p = 0.001, p < 0.001). In histopathological examination, increased macrophages and fibroblast population were observed in specimens from beta-D-glucan-treated animals.

CONCLUSION

The results indicate that in rat model, oral administration of beta-D-glucan causes a significant improvement in the healing of anastomotic wound impaired by long-term corticosteroid administration.