In this study, a polysaccharide (DOP) with molecular weight of 8.25 × 105 Da and monosaccharide composition of mannose (Man) and glucose (Glc) at a molar ratio of 4.2: 1 was isolated from Dendrobium officinale. The preventive effect on alcoholic gastric mucosa and liver injury of DOP was also investigated. In vitro data exhibited that the IC50 values of 1, 1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging ability and Fe2+ chelating capacity were 2.762 mg/mL and 6.667 mg/mL, respectively. Both the alcoholic gastric mucosal injury (AGMI) and alcoholic liver injury (ALI) animal models were used to investigate the gastrotrophic and hepatoprotective abilities of DOP. After administration of DOP, both gastric mucosal index (TNF-α, IL-6, PGE2, SOD, and MDA) and hepatic indicators (ALT, AST, SOD and MDA) improved compared to non-DOP groups. Histopathological results displayed that the DOP groups improved gastric epithelial defect and inflammatory cell redness caused by AGMI, and decreased vacuolization, hepatocyte necrosis and fibrosis caused by ALI. The results might be related to adjusting inflammatory factors, eliminating free radicals, and inhibiting lipid peroxidation capacities. These results manifested that DOP may be a therapeutic reagent to attenuate alcohol gastric mucosal and liver injury.
Keywords: Dendrobium officinale; gastric mucosal injury; liver injury; polysaccharides; structure.