Preventive effect of polysaccharides from the large yellow croaker swim bladder on HCl/ethanol induced gastric injury in mice

In the present study the preventive effect of polysaccharides from the large yellow croaker swim bladder (PLYCSB) on HCl/ethanol-induced gastric injury in ICR mice was investigated. A high dose of PLYCSB (50 mg/kg) was found to reduce the levels of the serum proinflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, as well as increase the levels of IL-4 compared with those in mice treated with a low dose of PLYCSB (25 mg/kg) and control mice. The somatostatin and vasoactive intestinal peptide serum levels in PLYCSB-treated mice were higher compared with those in control mice, whilst motilin and substance P serum levels were lower compared with those in control mice. The extent of the gastric injury in the mice treated with PLYCSB was lower compared with that in the control mice; however, the results obtained for mice treated with a high dose of PLYCSB were similar to those for omeprazole-treated mice. In addition, the superoxide dismutase and glutathione peroxidase activities of PLYCSB-treated mice were higher compared with those of the control mice, and similar to those observed in normal and omeprazole-treated mice. Furthermore, PLYCSB-treated mice showed levels of nitric oxide and malondialdehyde that were similar to those in the normal group. Using PCR and western blot analysis, it was demonstrated that PLYCSB significantly inhibited inflammation in the tissues of the HCl/ethanol induced gastric injury mice by downregulating the expression of inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α and IL-1β. These results suggest that PLYCSB has an inhibitory effect against gastric injury that is comparable to that of the gastric injury drug omeprazole. Therefore, PLYCSB has the potential to be used as a natural therapeutic drug.