Post on 16-Dec-2015
Parkinson's Disease
Animal Models and Possible Treatments.
What is an animal model?
What is an animal model?
A laboratory animal used in research that simulates processes comparible to those that occur in humans.
Two common animal models.
Lab rats.
Two common animal models.
Lab rats. Vertebrate model
Somehow resistant to MPTP
Two common animal models.
Lab rats. Vertebrate model
Somehow resistant to MPTP
Rotenone administered systemically - Chronic nigrostriatal cell loss, dopamine depletion, Akinesia, rigidity, tremor, flexed posture, piloerection.
Two common animal models.
Lab rats. Vertebrate model
Somehow resistant to MPTP
Rotenone administered systemically - Chronic nigrostriatal cell loss, dopamine depletion, Akinesia, rigidity, tremor, flexed posture, piloerection.
Fruit flies.
Invertebrate model
Two common animal models.
Lab rats. Vertebrate model
Somehow resistant to MPTP
Rotenone administered systemically - Chronic nigrostriatal cell loss, dopamine depletion, Akinesia, rigidity, tremor, flexed posture, piloerection.
Fruit flies.
Invertebrate model Dopamine is depleted. But is reversible by Hsp70 coexpression. Is there any use for this in human model?
Any similarities?
Possible treatments...
Possible treatments...
No two patients have the same experience of Parkinson's disease, and so any treatment given must suit the individual.
Possible treatments...
No two patients have the same experience of Parkinson's disease, and so any treatment given must suit the individual.
You must consider -
Possible treatments...
No two patients have the same experience of Parkinson's disease, and so any treatment given must suit the individual.
You must consider - Age Lifestyle Personal Preference etc.
Drug treatments...
Drug treatments...
Levodopa
Taken in by dopaminergic neuron terminals and converted to dopamine. Only 1% reaches the brain if dose is metabolised.
Side effects - Nausea, Vomiting Anorexia Postural hypotension Involuntary movement Urine discolouration
Drug treatments...
Enyme inhibitors Inhibits enzyme which breaks down dopamine (MAOB), prolonging the effect of
remaining dopamine in the brain.
Side effects - Sleep disorders Vertigo Dry mouth Skin rash Depression
Drug treatments...
Dopamine agonists
Mimic natural dopamine by stimulating dopamine receptors in the brain.
Side effects - Nausea, vomiting Dizziness Headache Sudden sleep (patients can't drive) Hallucinations
Surgery...
Deep Brain Stimulation (DBS)
Reduces distressing symptoms such as rigidity.
Tiny wire electrodes are implanted in the Basal Ganglia. They are connected to an Implantable Pulse Generator in the chest.
Turn pulse on: symptoms reduce.Turn pulse off: symptoms return.
Cost €40,000 to €50,000!
Ideal candidates are younger and fit. Must have no history of severe depression.
What does the future hold?
What does the future hold?
Stem cell research...
Scottich scientists are creating dopamine-producing neural cells.
These can be injected into patients brain to reverse the effects of Parkinson's.
BUT - Will the injected cells be accepted by the patient? Or will they be destroyed in a natural immune response.
This research is ongoing. It may take 20 years before it is ready for widespread use.
References
Betarbet, et al. Nat Neurosci 2000; (12):1301-6. Parkinson's disease A nurse's handbook 2008.
http://news.scotsman.com/