Parkinson’s disease (PD) is the second most common chronic neurodegenerative disease after Alzheimer’s disease and is associated with a progressive loss of dopaminergic neurons in the substantia nigra (SN).
The neuronal loss leads to deficiency in dopamine (DA) in the striatum, which is responsible for characteristic motor symptoms such as akinesia, bradykinesia, muscle rigidity and tremor at rest. Pharmacological treatment with L-DOPA as well as surgical treatments such as deep brain parkinsonian symptoms but do not repair the dopaminergic pathway or prevent its degeneration. Therefore, the novel therapies are highly awaited by employing relevant in vitro and in vivo models.
In vitro testing
1A. Test of biological effect on cell death.
1B. Determining the level of the baseline extracellular concentrations of different factors such as: dopamine (DA), dihydroxyphenylacetic acid (DOPAC), etc.
After in vitro screening, the subsequent in vivo studies will be proposed in order to further confirm these in vitro results.
In vivo evaluation
In order to induce PD in animals, two most frequently used toxins are therefore employed in rodents as an experimental model:
- 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)
- 6-hydroxydopamine (6-OHDA).