Single dose toxicity of polyphenols effective parts from Punica granatum and their protective effect on ethanol-induced gastric ulcer in rats / 中国药理学通报

ABSTRACT

Aims To study single dose toxicity of poly-phenols effective parts from Punica granatum,to eval-uate their safety,and thus to provide a theoretical basis for drug development and clinical use.To observe their protective effect on ethanol-induced gastric ulcer in rats.Methods 50 healthy Kunming mice were ran-domly divided into five groups and given different doses of polyphenols’effective parts from Punica granatum via intragastric administration.Toxicity and death in each group of mice were observed and recorded after administration for 14 d.The median lethal dose was calculated by Bliss method.70 rats were randomly di-vided into normal group,model group(constant volume of normal saline),sanjiuweitai particles(1 850 mg· kg-1 )group,colloidal bismuth subcitrate (33 mg · kg-1 )group and polyphenols effective parts from Puni-ca granatum low-dose,medium-dose,high-dose(430, 852,1 704 mg·kg-1 )groups.On the 9th day of 10 days’gavage,all except the normal group were fed ethanol (1.5 mL/only)to induce gastric mucosal inju-ry in rats with acute gastric ulcer.Gastric ulcer index, the rate of ulcer inhibition were calculated for each group.The morphological changes of gastric mucosa were observed.The gastric mucosa levels of PGE2 , NO,SOD and MDA were determined.Results The LD50 and 95%confidence limit of the polyphenols’ef-fective parts from Punica granatum were 8 520.9 mg· kg-1 and 7 291.2 ~9 914.4 mg·kg-1,respectively. Pathology showed that the organs receiving dose of 16 000 mg · kg-1 had different degrees of damage . Compared with the model group,the extract from Puni-ca granatum significantly repaired the gastric mucosa, and significantly increased the gastric mucosa levels of NO and reduced MDA content,and improved SOD content and the levels of PGE2 .Conclousion The dose of 5 063 mg · kg-1 of polyphenols effective part from Punica granatum showed no death.The dose of 16 000 mg · kg-1 of polyphenols effective parts from Punica granatum could cause varying degrees of dam-age in heart,liver,lung,kidney or the death of mice. The LD50 and 95% confidence limit of the polyphenols effective parts from Punica granatum were 8 520.9 mg ·kg-1 and 7 291.2 ~9 914.4 mg·kg-1,respective-ly.The extract from Punica granatum plays a protective role against gastric mucosa damage induced by absolute ethanol,and the mechanism may be related to promo-ting ulcer epithelial cells synthesis,enhancing mucosal regeneration function,regulating NO content and en-hancing antioxidant capacity.