Evaluation of antihypoxic activities of corn silk and Vici faba hulls in mice

Background and purpose: Hypoxia occurs especially in heart diseases, ischemia and heart attack, and finally causing death. Hypoxia causes oxidative stress involving production of reactive oxygen species (ROS). Compounds with antioxidant activity can scavenge ROS and are able to exhibit antihypoxic property. Zea mays and Vicia faba are well known plants with distinctive antioxidant activities. Nothing is known about protective effect of these plants against hypoxia-induced lethality in mice.Material and methods: Protective effects of corn silk and Vicia faba hull methanol extracts against hypoxia-induced lethality in mice were evaluated by three experimental models of hypoxia, asphyctic, haemic and circulatory models. Analysis of variance was performed followed by Newman-Keuls multiple comparison test was used to determine the differences in means. Result: Antihypoxic activity was pronounced in asphyctic model for both extracts where extracts at 62.5 mg/kg prolonged survival time respect to control group (p<0.001). At this dose, corn silk extract showed the same activity of phenytoin which used as positive control (p> 0.05). In circulatory model, extracts showed marked protective activities, too. At 31.25 mg/kg, both extracts prolonged survival time which were significantly higher than control groups (p<0.05). In haemic model, extracts were not so effective. Only in the highest tested dose, i.e. at 125 mg/kg, extracts significantly prolonged survival times. Conclusion: Extracts showed good protective effects against hypoxia in some model. Presence of polyphenols in these plants may be a proposal mechanism for their antihypoxic activities.

Keywords:

Asphyctic hypoxia , Haemic hypoxia , Circulatory hypoxia , Corn silk , Vici faba , Zea mays.