Effects of tachykinin neuropeptide NKB and A<i>β</i> (25-35) on antioxidant enzymes status in 17<i>β</i> estradiol treated aging female rats

Abstract

Aging is the leading risk factor for neurodegenerative diseases and oxidative stress involved in the pathophysiology of these diseases. These changes increase during menopausal condition in females when the level of estradiol is decreased. The aim of the present study was to determine the effect of tachykinin neuropeptide, Neurokinin B (NKB) and Amyloid beta fragment Aβ (25 -35) on 17β estradiol (E2) treated aging female rat synaptosomes of different age groups. Aging brain functions were assayed by measuring the activities of antioxidant enzymes-superoxide dismutase (SOD) and monoamine oxidase (MAO) with neuropeptides. An in-vitro incubation of Aβ (25 -35) in E2 treated brain synaptosomes showed toxic effects on all the parameters. However, NKB and NKB combined with Aβ (25 -35) showed stimulating effects in E2 treated rat brain synaptosomes. In the present study, an increase in activity of SOD and decrease in the level of MAO, in the presence of NKB and combined NKB and Aβ in E2 treated brain synaptosomes of aging rats. This study elucidates that treatment of NKB and Aβ with E2 in combination exerts more protective influence than their individual application, against excitotoxicity in age related changes.