17-β estradiol in the acetylcholinesterase activity and lipid peroxidation in the brain and blood of ovariectomized adult and middle-aged rats

Abstract

AimsTo investigate the 17-β estradiol in the acetylcholinesterase activity and lipid peroxidation in the brain and blood of ovariectomized rats of different ages. Main methodsAnimals were randomly assigned into three experimental groups of each age (n=6). Control groups consisted of adult (sham-A) and middle-aged (sham-MA) female rats, ovariectomized adult (OVX-A) and middle-aged (OVX-MA) rats without estrogen therapy reposition, and ovariectomized adult (OVX+E2-A) and middle-aged (OVX+E2-MA) rats treated with 17-β estradiol for 30days. After this period, AChE activity and lipid peroxidation were measured in the brain and blood. Key findingsThe AChE activity increased (p<0.05) in striatum (ST) in OVX-A, OVX+E2-A and OVX-MA, and hippocampus (HP) in OVX-MA. The enzyme activity decreased (p<0.05) in ST of OVX+E2-MA, and cerebral cortex (CC) in OVX+E2-A, OVX-MA and OVX+E2-MA. Blood AChE activity increased (p<0.05) in OVX+E2-A and decreased (p<0.05) in OVX-MA. Lymphocyte AChE activity increased (p<0.05) in OVX-A and OVX+E2-A and decreased (p<0.05) in OVX-MA. Lipid peroxidation increased (p<0.05) in ST of OVX-A, CC of OVX-A and OVX-MA, HP of OVX-A, and cerebellum (CE) of OVX-A, OVX-MA, and OVX+E2-MA. Lipid peroxidation decreased (p<0.05) in ST, CC and CE of OVX+E2-A, and ST and HP of OVX+E2-MA. Similar values of lipid peroxidation to control groups were found in ST and HP of OVX-MA, HP of OVX+E2-A and CC of OVX+E2-MA. Significance17-β estradiol is able to modulate the AChE activity and non-neuronal cholinergic response as well as to reduce lipid peroxidation. Its response is dependent on the age and brain structure analyzed.