Study of the gastrointestinal protective effects of polysaccharides from Angelica sinensis in rats

We studied the protective effects of polysaccharides isolated from the root of Angelica sinensis (Oliv.) (Danggui) on gastrointestinal damage induced by ethanol or indomethacin in rats. Oral administration of ethanol provoked a marked hemorrhagic damage in the glandular mucosa, which was accompanied with a significant increase of myeloperoxidase (MPO) activity, a marker enzyme for inflammation and neutrophil infiltration. An extract from Angelica, which mainly consisted of polysaccharides (95%) (AP), dose- dependently prevented gastric mucosal damage. This ulcer protective effect could last at least 12 h after administration. Prostaglandin E₂ produced a similar anti-lesion effect. AP and prostaglandin E₂ also reduced mucosal MPO activity. Indomethacin-induced gastrointestinal damage, another neutrophil- dependent lesion model in the gastrointestinal tract, was also prevented by AP pretreatment. The present findings suggest that polysaccharides from Angelica possess an anti-inflammatory action, perhaps through the inhibitory action on neutrophil infiltration in the gastrointestinal mucosa. AP could potentially be useful to prevent any neutrophil-dependent mucosal injury in the gastrointestinal tract.