Examining the impact of caspase activities in PD animal model & differentiated ReNcell VM

Abstract

Parkinson's disease (PD) is a neurodegenerative disorder that is characterised by uncontrollable shaking, muscular rigidity and cognitive impairment, due to low levels of dopamine caused by loss of dopamine containing neurons (DCN). The loss of DCN has been strongly associated with Caspase mediated apoptotic death. At present there are many studies that indicate exercise is beneficial in PD treatment, but there is a lack of research exploring the potential pathways, which exercise can activate and suppress to provide such positive and even negative effects. This study is the first to explore the effect of treadmill exercise on the level of Caspases, along with CAMK-IV protein in different brain regions of MPTP-treated rat model, using WB analysis. The results of this research has demonstrated reduction or completely suppression of some active Caspases, as well as, elevated amount of CAMK-IV in different brain regions of exercised PD animal model. To determine how exercise is reducing and inhibiting activation of Caspases, the first step was to identify how Caspases are stimulated, using ReNcell VM stem cell line that had been differentiated and treated with 6OHDA. The results of the study demonstrated 6OHDA triggered Caspase mediated apoptotic death of dDCN via PERK ER stress and NFκB classical pathway. IF, WB and cell viability analysis, using a wide range of inhibitors, showed that Caspase-2 is activated by the PERK pathway of ER stress and NFB classical pathway in 6OHDA treated dDCN. 6OHDA triggered activation of Caspase- 8 by the classical pathway in NFB mediated death of dDCN. 6OHDA triggered Caspase-4 activation but the exact mechanism involved remains to be identified. Only through understanding the molecular pathways regulating death of DCN in PD, new potential targets for therapy may be identified, which may ultimately reduce further death of DCN and slow PD progression. This proposed study has the potential to seek for more efficient drugs, which can suppress Caspase activation by targeting key targets in the pathways that the Caspases follow. These new specific targeted drugs could be used with treadmill exercise to achieve maximum effect, by slowing down or inhibiting further death of DCN.