Influence of wild strawberry tree (Arbutus unedo L.) leaf extract on DNA and activity of antioxidative enzimes in kidney, liver and brain of Lewis rat

Obična planika (Arbutus unedo L.) je mediteranska biljka koja se već stoljećima koristi u narodnoj medicini. Listovi obične planike sadrže visoki udio fenolnih spojeva koji djeluju antioksidacijski, antikancerogeno, antimutageno i protuupalno. Fenolni spojevi u biljkama potiču aktivnost antioksidativnih enzima važnih za borbu s reaktivnim metabolitima kisika čije povišene koncentracije mogu oštetiti stanicu i dovesti do pojave raznih bolesti. Cilj ovog istraživanja je utvrditi učinak ekstrakta listova obične planike na: aktivnost antioksidativnih enzima (SOD i katalaza); lipidnu peroksidaciju te primarna oštećenja DNA u stanicama mozga, jetre i bubrega štakora soja Lewis oba spola. Pokusne skupine tretirane su vodenim ekstraktom lista obične planike (200 mg/kg) per oralno tijekom 28 dana. Utvrđeno je smanjenje aktivnosti katalaze i blago smanjenje aktivnosti superoksid dismutaze u stanicama bubrega štakora oba spola. Tretman nije statistički značajno utjecao na aktivnost katalaze i superoksid dismutaze, kao ni na stupanj lipidne peroksidacije u jetri štakora oba spola. U stanicama mozga ženki zabilježena je statistički značajno povišena vrijednost aktivnosti superoksid dismutaze. U mužjaka štakora došlo je do statistički značajnog povećanja stupnja lipidne peroksidacije u mozgu. Potencijalni genotoksični učinak vodenog ekstrakta listova obične planike određen je komet testom u alkalnim uvjetima. Rezultati ukazuju na oštećenje DNA u stanicama jetre mužjaka i ženki, te vrlo blago oštećenje DNA u stanicama bubrega mužjaka. Daljnja istraživanja potrebna su kako bi se odredila najprikladnija doza i trajanje tretmana običnom planikom koji će imati najbolji terapijski učinak bez štetnih nuspojava.Strawberry tree (Arbutus unedo L.) is a Mediterranean plant which is used for centuries in folk medicine. The leaves contain high concentration of the phenols which have antioxidational, anticancerogenic, antimutagenic and antinflammatory effects. Phenols can stimulate the activity of antioxidant enzymes important for the endogenous fight with ROS, whose elevated concentrations can damage the cell and lead to various diseases. The aim of this study is to determine the antioxidant activity of Strawberry tree leaf aqueous extracts on: activity of antioxidant enzymes (SOD and catalase); lipid peroxidation and primary DNA damage in brain, liver and kidney cells of the Lewis rats breed of both sexes. Test groups of animals were treated with the aqueous extract of a strawberry tree leaf (200 mg / kg) per orally for 28 days. Reduction of catalase activity and a slight reduction of superoxide dismutase activity in rat kidney cells of both sexes were found. The treatment did not significantly affect the activity of catalase and superoxide dismutase, as well as the level of lipid peroxidation in the rat liver cells of both sexes. In the brain cells of the female rats, statistically significant increase of the catalase activity was observed. In brain cells of male rats statisticaly significant increased level of lipid peroxidation was recorded. Potential genotoxic effect of the aqueous leaf extract of strawberry tree is determined by using a comet assay in alkali conditions. Results indicate that there is DNA damage in the liver cells of male and female rats, very low DNA damage in the kidney cells of the males rats. Further studies are needed to determine the most appropriate dose and duration of treatment that will have the best therapeutic effect without adverse side effects