Stinging nettle (Urtica dioica L.) has been traditionally used in treatment numerous health problems, including hypertension and hyperlipidemia. The aim of this study was to evaluate potential antihypertensive and antioxidant effects of chronic intake of stinging nettle leaf extract (UE) in spontaneously hypertensive rats (SHR).Design and method:
SHR were divided into 5 experimental groups. Throughout 4 weeks long study, control group (SHRC) received tap water, positive antihypertensive control group (SHR+L) received 10 mg/kg/day of losartan, while SHR+UE10, SHR+UE50 and SHR+UE200 groups were treated with 10, 50, and 200 mg/kg/day of dry aqueous-methanolic UE. Losartan and UE were dissolved in 0.5 ml of water, and given to the animals by gavage. At the end of the treatment mean arterial pressure (MAP) was measured directly in anesthetized animals, and blood samples were collected for erythrocyte superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities. Serum lipid peroxidation level was assessed by total thiobarbituric acid-reactive substances assay (TBARS).Results:
MBP dropped significantly in SHR+L, SHR+UE50, and SHR+UE200 group. Furthermore, all three UE doses significantly increased SOD and CAT activities, but not the GPx activity. Antioxidant enzyme activities remained unchained in SHR+L group. Serum lipid peroxidation level was decreased in all three tested UE doses while it remained unchanged in SHR+L group.Conclusions:
Our results indicate that all three UE doses improve antioxidant enzymes activity and reduce serum lipid peroxidation level in SHR. Furthermore, MAP reduction in SHR+UE50 and SHR+UE200 is similar to losartan therapy. Therefore, UE expresses beneficial effects in genetically induced hypertension.