Guar galactomannan ameliorates radiation-induced intestinal injury in mice

Guar galactomannan (GGM), a widely used hydrocolloid in the food industry, was evaluated for its biological activity with respect to radioprotection. In an in vitro lymphocyte proliferation study, GGM showed significant proliferation of blood lymphocytes at a concentration of 50 μg/ml. The survival study of 30 days showed that GGM pre-treatment improves the survival in irradiated (7.5 Gy) mice to 70% which otherwise is just 30% in the control irradiated group. On day 3, the WBC count was maintained in the GGM pretreated IR mice group compared to the irradiated control group. Serum enzyme levels in the liver of the GGM pretreated irradiated group were reduced, spleen and thymus weight indices and antioxidant enzymes were increased in the intestine of the GGM pretreated irradiated group compared to the irradiated group. Histopathological studies of ileum and jejunum on day 3 revealed that there was less damage in the crypt and height of villi in the GGM pretreated IR mice group compared to the irradiated control group. In the differential gene expression of jejunum, a total of 43 genes showed differential expressions, suggesting their involvement in the biological response to the effect of galactomannan treatment on irradiated mice. Differential expression of genes shows that upregulation of the genes is related to limiting the damage to the intestine and stem cell genes involved in cell differentiation and function. Moreover, genes associated with apoptosis and inflammation were shown to be downregulated in the GGM-pretreated IR group. These results suggest that GGM improves mice from radiation-induced injury by increasing WBC count, reducing acute liver damage, maintaining spleen and thymus weight, increasing the levels of antioxidant enzymes and altering gene expression.