Protective effect of oleuropein on the brain tissue in D-Galactose-induced aging in rat model

Abstract Background Many researches have indicated that Oleuropein (OLE) has potential ability to decrease oxidative stress and inflammation. So, In the present investigation, we explored the protective effect of OLE on brain aging induced by d-galactose (D-Gal) in a rat model.. Methods and results In this study, 40 Wister male adult rats were categorized into 5 groups. Group 1 received normal saline, while group 2 was administered 100 mg/kg/ip D-Gal. The rats in groups 3 to 5 were orally administered D-Gal (100 mg/kg) once a day. Additionally, these groups were simultaneously subjected to different doses of OLE (20, 40 and 80 mg/kg, respectively) through oral administration. All administrations were done once a day for 8 consecutive weeks. 24 hours after last treatment motor activity and memory impairment were evaluated. Then, the rats were sacrificed and brain samples were collected for evaluating biochemical markers (BDNF, MDA, PC, GSH, GPX, CAT , SOD, IL-1β and TNF-α) and gene expression (SIRT1 and PGC1). The results showed that D-Gal significantly reduced motor activity and memory performance (P<0.05). It also significantly reduced the GPx, CAT and SOD activities, GSH and BDNF levels as well as SIRT1 and PGC1 expression, and, significantly increased PC, MDA TNF-α and IL-1β levels in the brain tissue (P<0.05). Administration of OLE restored all of the above parameters close to control group. Conclusion The findings illustrated that OLE attenuates locomotor , cognitive dysfunction and age related neuronal dysfunction. The neuroprotection of OLE can be attributed to its potential antioxidant and anti-inflammatory properties and activation of age preventing genes.