Protective effect of polysaccharide from Hizikia fusiformis against ethanol-induced toxicity

Polysaccharide extracted from Hizikia fusiformis (Hf-PS-1) exhibited protective effects against ethanol-induced peptic injury. In in vivo assay, the ethanol group exhibited decrease of total glutathione (GSH) and increase of jun N-terminal kinase (JNK) phosphorylation relative to the control group, whereas levels were significantly increased and decreased, respectively, in the Hf-PS-1 group. Hf-PS-1 reduced ethanol-induced gastric injury. In in vitro assay, ethanol induced IEC-6 cells' death in a dose-dependent manner. Ethanol decreased the phosphorylation of Shc and the binding of Grb2 to Shc, and Hf-PS-1 pretreatment increased them. Ethanol also induced the phosphorylation of JNK and extracellular signal-regulated kinase (ERK), whereas Hf-PS-1 pretreatment decreased JNK activation but not ERK. Co-treatment with JNK inhibitor and ethanol decreased GSH levels, indicating that JNK phosphorylation is a critical factor during ethanol-induced injury. Therefore, Hf-PS-1 may be useful to protect against ethanol-induced gastrointestinal injury.