The Roles Of The Mesencephalic Micro-environmental Alteration In Parkinson's Disease

Parkinson's disease (PD) is a progressive neurological disorder with a prevalence of l%-2% in people over age of 50. PD is characterized by the degeneration of nigrostriatal dopaminergic neurons and the neurological hallmark of PD is the presence of Lewy bodies . Now along with the progress of medicine , people's lives have been expanded and our society has more and more old folks. PD has become one of the most important diseases threatening people's health. Thus, how to prevent or treat it has become the hotspot of morden medicine.Now the studies on PD's therapies are all about how to help or save dopaminergic neurons, which all have more or less difficulty and shortcoming in themselves. More than 50% cells in CNS are Astrocytes. Astrocytes provide metablic and trophic support for neurons. More recently, it has been suggested that the astrocytes would promote the degeneration of nigrostriatal dopaminergic neurons.Rotenone is conbutribute to the inhibition of NADH: ubiquinone oxidoreductase viactivity. Using primary astrocyte cultures from the mesencephalon of Wistar rats, We observed the LDH levels of their were higer than normal (20nM,30nM), while the GSH and GDNF levels of their were lower than normal(40nM)when astrocyte cultures were exposed to rotenone,.Rotenone inhibit astocyte's mitochondiial complex I, thus disrupt astrocyte's respirary chain. The disruption cause the excessive generation of ROS which diminish GSH . GSH is an important scavenger for ROS, which protects cell fromoxidative stress. Most GSH in brain are present in glial cells, Similarly,the activity of superoxide dismutase and complex I in astrocytes is significantly higher than that in neurons. Our results indicate the occurrence of oxidative stress or mitochondrial dysfunction in normal or activated glial cells may contribute to the death of the nigral dopaminergic neurons in PD. It has been said that GDNF has a specific neurotrophic effect on dopaminergic. The decrease of GDNF expression and GSH level hi treatment group may cause dopaminergic neurons more sensitive to damage.