Variations in antioxidant enzyme levels of rats exposed to ethanol extracts of Convolvulus species

Abstract

The use of plants in the treatment of various diseases has a history as old as humanity. Turkey, with its rich flora, is a unique resource for this kind of investigations. Convolvulaceae genus is used for the prevention of various neurodegenerative diseases and intestinal problems in the traditional folk medicine. It is also reported in the scientific literature that these species possess an inhibition potential for the growth of certain tumor cells. In order to evaluate the potential toxic effects of these species, 1% ethanol extracts were administered to experimental groups and the antioxidant enzyme activities aside from the lipid peroxidation levels were determined in the selected organs. In comparison to control group, a decrease in liver catalase (from 10.69 to 8.61, 7.58 and 5.60. U/mg protein for Convolvulus phrygius, Convolvulus aucheri and Convolvulus galaticus, respectively) and glutathione peroxidase (from 2.21 to 2.12, 0.85 and 0.76. U/mg protein for C. phrygius, C. aucheri and C. galaticus, respectively) activities were observed in all groups that were fed with ethanol extract (1%) for a period of one month. A decrease in antioxidant enzyme activities along with the increase in lipid peroxidation levels and blood biochemical parameters is a significant marker of liver injury. Similar results were found for the kidney except from the group fed with C. phrygius extract. It is obvious that studied concentrations of Convolvulus species inhibits the liver/kidney antioxidant enzymes in vivo and stimulates the loss of membrane function via peroxidation. Since all these fluctuations in antioxidant enzyme activities cause toxicity in the related organs, further investigations are strongly recommended to find the optimum dose and exposure time prior to medical uses of these species. © 2015 Elsevier B.V..