Flaxseed lignan secoisolariciresinol diglucoside ameliorates experimental colitis induced by dextran sulphate sodium in mice

The effect of flaxseed lignan secoisolariciresinol diglucoside (SDG) on ulcerative colitis was examined. Experimental colitis was induced in mice by administering 5% dextran sulphate sodium (DSS). SDG in doses of 100 and 200 mg/kg/day and 5-aminosalicylic acid (positive control) were given orally for 3 days before and during DSS administration. Oral SDG treatment significantly decreased the disease activity index and increased colon length. Histological examination revealed that the oral administration of SDG suppressed DSS-induced erosion, ulceration, crypt abscesses and oedema. Furthermore, colonic myeloperoxidase activity and TNF-α expression declined remarkably following treatment with SDG. Additionally, oral SDG treatment significantly increased the expression of several mucoprotection markers, to include zona occludens-1, Tollip and trefoil factor 3, and thus restored intestinal permeability. These results suggested that oral SDG treatment can alleviate DSS-induced colitis and might be a promising supplement for the amelioration of inflammatory bowel disease.