RÉSUMÉ
Objective: To test the anti-plateau hypoxia effect of Potentilla anserina polysaccharide(PAP), Cynomorium songarieum Rupr. polysaccharide(SCRP), Sphallerocarpus gracilis polysaccharide(SGP)and Lilium brownii polysaccharide(LP), and then investigate the protective effect of most effective polysaccharide on the high altitude cerebral edema(HACE)and high altitude pulmonary edema(HAPE)in rats. Methods: PAP, CSRP, SGP and LP were prepared by the water extraction-alcohol precipitation method. The normobaric hypoxia test and acute hypoxia test were performed to find out the polysaccharide with the best anti-hypoxia effect and the related dose-dependent effect in mice. A large hypobaric hypoxia chamber stimulating 8000 m altitude was used to investigate pathological changes and water contents in rat brain and lung tissue before and after hypoxia, and the concerned oxidative stress and inflammation related parameters were also measured. The protective effect of PAP on the high altitude cerebral and pulmonary edema was evaluated by the rat model experiments. Results: PAP showed the best and dose-dependent anti-hypoxia effect among the four polysaccharides. The water content in brain and lung tissues of rats increased obviously in the hypoxia model(HM)group, and the brain tissue cell hierarchical fuzzy, lung tissue congestion and edema as well as the heavy inflammatory cell infiltration, widening of alveolar interval and thickening of alveolar wall were also found in the HM group. The enzymatic activity of SOD was notablely depressed, while both the MDA and IL-1β contents in brain and lung tissues remarkably increased(P<0.01)in the HM group. Com- pared with the HM group, the water content in the rat brain and lung tissues significantly decreased in each of the different dose PAP groups(P<0.05 or P<0.01), and the inflammatory cell infiltration, alveolar interval, and thickness of alveolar wall all notabely decreased in the HM group. Furthermore, the enzymatic activity of SOD increased, while both the MDA and IL-1β contents decreased, all significantly in the PAP groups than in the HM group(P<0.05 or P<0.01). Conclusion: PAP showed a good anti-hypoxia effect and effectively inhibited HACE and HAPE to exert a certain protective effect in a rat model.
RÉSUMÉ
Objective To investigate the effects of ω-3 polyunsaturated fatty acid(PUFA)on oxidative stress produc-tion and apoptosis in hippocampus of neonatal rats with brain injury induced by lipopolysaccharide(LPS). Methods Forty-eight neonatal Sprague Dawley rats(3 days)were randomly divided into control group,LPS group,ω-3 PUFA group and ω-6 PUFA group,with 12 rats in each group. The rats in the LPS group,ω-3 PUFA group and ω-6 PUFA group were given 0. 6 mg·kg - 1 LPS via intraperitoneal injection,then equal volume of saline,ω-3 PUFA and ω-6 PUFA was immediately given via intraperitoneal injection respectively;while the rats in the control group were all given equal volume of saline. The rats in each group were sacrificed at 24 hours after intraperitoneal injection with saline or fat emulsions to obtain the hippocampus. The levels of superoxide dismutase(SOD)and malondialdehyde(MDA),reduced glutathion(GSH),oxidized glutathione(GSSG) were detected and GSSG/ GSH was calculated. The apoptotic index was measured by terminal deoxynucleotidyl transferase-me-diated dUTP nick end labeling. Results Compared with the control group,the levels of SOD and GSH in hippocampus of rats in the LPS group,ω-6 PUFA group and ω-3 PUFA group were significantly decreased(P < 0. 05),and the levels of MDA, GSSG and the ratio of GSSG/ GSH were significantly increased(P < 0. 05). Compared with the LPS group,the levels of SOD and GSH in hippocampus of rats in ω-6 PUFA group were significantly decreased(P < 0. 05),the levels of MDA,GSSG and the ratio of GSSG/ GSH were significantly increased(P < 0. 05);the levels of SOD and GSH in hippocampus of rats in ω-3 PU-FA group were significantly increased(P < 0. 05),the levels of MDA,GSSG and the ratio of GSSG/ GSH were significantly de-creased(P < 0. 05). Compared with the ω-6 PUFA group,the levels of SOD and GSH in hippocampus of rats in ω-3 PUFA group were significantly decreased(P < 0. 05),the levels of MDA,GSSG and the ratio of GSSG/ GSH were significantly in-creased(P < 0. 05). The apoptotic index in the LPS group,ω-6 PUFA group and ω-3 PUFA group was higher than that in the control group(P < 0. 05). The apoptotic index in the ω-6 PUFA group was higher than that in the LPS group(P < 0. 05). The apoptotic index in the ω-3 PUFA group was lower than that in the LPS group and ω-6 PUFA group(P < 0. 05). Conclusion ω-3 PUFA can alleviate the oxidative stress,and decrease the apoptosis of hippocampus in neonatal rats with brain injury in-duced by LPS. So it has a neuroprotective effect in brain injury induced by LPS.