Protective effect of sericin peptide against alcohol-induced gastric injury in mice.
BACKGROUND
Sericin peptide (SP) has shown a powerful anti-oxidant property in a host of studies. The present study was designed to investigate the possible protective effects of SP against alcohol-induced gastric lesions in mice and to explore the potential mechanisms.


METHODS
Animals were randomly divided into 5 groups: control, alcohol (56%, 14.2 ml/kg), SP-treated mice (0.2, 0.4, 0.8 g/kg). Mice were pretreated with SP before administering alcohol, the concentration of ethanol in serum and urine, the contents of malondialdehyde (MDA), glutathione (GSH) and the glutathione peroxidase (GSH-PX), catalase (CAT) and superoxide dismutase (SOD) activities in the gastric mucosa were measured, subsequently, the pathological evaluation of stomach was also observed.


RESULTS
Of the animals pre-treated with SP (0.4, 0.8 g/kg), the concentration of ethanol in serum was significantly decreased, while increased in urine as compared to the alcohol-administered alone animals. Alcohol administration caused severe gastric damage as indicated by markedly increased MDA levels and decreased antioxidants, such as reduced GSH, GSH-PX and SOD in the gastric tissue while the CAT activity was not altered. On SP administration there was a reversal in these values towards normal. Histopathological studies confirmed the beneficial role of SP, which was in accordance with the biochemical parameters.


CONCLUSIONS
SP could protect gastric mucosa from alcohol-induced mucosal injury. These gastroprotective effects might be due to increasing 'first-pass metabolism' in the stomach and hastening ethanol elimination directly through the urine. SP might also play an important role in the protection of the structure and function of gastric mitochondria, at least partly based on their anti-oxidant effect.
Li
You-gui
YG
Sericultural Research Institute, Zhejiang Academy of Agricultural Science, Hangzhou, Zhejiang 310021, China.
Ji
Dong-feng
DF
Lin
Tian-bao
TB
Zhong
Shi
S
Hu
Gui-yan
GY
Chen
Shi
S
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D019610:Cytoprotection; D000431:Ethanol / Q000097:blood / Q000633:toxicity* / Q000652:urine; D005753:Gastric Mucosa / Q000187:drug effects* / Q000473:pathology; D005978:Glutathione / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D047030:Sericins / Q000032:analysis / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000378:metabolism
D000596:Amino Acids; D047030:Sericins; D000431:Ethanol; D013482:Superoxide Dismutase; D005978:Glutathione