Life stories Parkinsons disease Parkinson's Disease is a progressive disorder that causes problems with movement, including tremor, muscle rigidity and slowness.
The disease has an overwhelming impact on those it affects and has a limited repertoire of drug therapies available, each with problematic side effects. Stem cell therapy is an exciting prospect in the treatment of several neurodegenerative conditions.
In addition to highlighting the cell replacement therapies available, the article also provides a chronology of research into this emerging field over the last 30 years. After years of battling with the disease, Ali now has difficulty speaking and coordinating his movements but remains an inspiration to many The Guardian, ; Tim Dahlberg, The Seattle Times, PD affects around 6.
It is currently an incurable disease associated with irreversible loss of the dopaminergic neurons in the substantia nigra SN and striatum, which are structures of the basal ganglia, essential for fine motor control and initiation of movement Barker, Cicchetti and Neal, As the central nervous system CNS has a limited capacity to regenerate its neurons, this has a devastating effect on motor function.
Current drug therapies target symptom management, and at present there are no cures for PD. This begs the question, is there potential for a treatment in the future and how does cell replacement therapy fit into the picture?
Today there is a greater understanding of the underlying causes of these symptoms.
However, what triggers degeneration of the dopaminergic neurons in the first place remains unknown. Diagnosis of PD is still a clinical diagnosis based on the four cardinal symptoms, as there is no definitive test.
On post-mortem examination, the SN of PD patients has a pale appearance. This is because dopaminergic neurons are rich in neuromelanin, the substance that gives rise to the dark pigmentation of the SN in normal adults Zecca et al.
Under a microscope abnormal aggregates of protein can be seen, known as Lewy bodies. This demonstrates the potential of environmental toxins having a role and has provided one of the principal animal models of PD Sian et al.
Current drug therapy As PD is caused by a loss of the dopaminergic neurons, the main drug therapies focus on replenishing the dopamine within the basal ganglia.
Dopamine precursors such as Levodopa and dopamine agonists form the basis of current therapy. Levodopa is augmented with a DOPA decarboxylase inhibitor to reduce peripheral conversion, ensuring the majority of Levodopa is converted to dopamine within the CNS Poewe and Antonini, Monoamine oxidase B inhibitors can also be prescribed to reduce the breakdown of dopamine within the brain.
While these drugs initially relieve patients of their symptoms, their therapeutic benefit diminishes with time. Unfortunately, these drugs also have unpleasant side effects such as dyskinesia, which is the occurrence of involuntary movements.
Although medication is the mainstay of PD management, there are alternative treatments such as speech and language therapy or surgical options such as deep brain stimulation DBS Odekerken et al. Current therapies have their limitations as they focus on symptomatic relief only and do nothing to reverse or slow down the progression of the disease.
As PD is caused by degeneration of dopaminergic neurons, it stands to reason that differentiated stem cells could be implanted to replace lost neurons and consequently re-innervate the striatum.
The case for cell replacement therapy Cell replacement therapy is a promising avenue into the investigation and treatment of neurodegenerative diseases. The CNS is unable to regenerate its own neurons, due to the physical and chemical barriers formed by glial scars Ohtake and Li, Stem cells have the ability to multiply and differentiate down any cell line, this is known as pluripotency.
Current research is focussing on the pluripotent potential of various forms of stem cells. By inducing stem cells to differentiate under the correct conditions, dopaminergic neurons can be created.
These neurons can be transplanted into a patient with PD, replacing their dopamine levels and providing symptomatic relief. The idea of treating PD using cell replacement therapy is not a new one; research in this area started in the early s.
Studies investigating the effects of foetal neuronal tissue in PD patients yielded promising results. A study published intransplanted foetal ventral mesencephalic tissue which would later develop into the basal ganglia rich in dopaminergic neuroblasts precursors from aborted foetuses into the striatum of two patients with idiopathic PD Peschanski et al.
The team followed up the patients and compared PET scan data of Flurodopa dopamine with a radioactive isotope with motor changes.Articulation and Treatment of Parkinson’s Disease Essay Sample.
Introduction. The factual cause of Parkinson’s is unknown. Parkinson’s disease is a progressive disorder characterized primarily by uncontrollable tremors in the limbs, a shuffling gait, and generalized muscular rigidity.
It is usually not fatal, but leads to change in the entire body. Cell models of Parkinson's disease generated from stem cells could help researchers screen drugs more efficiently than in currently available animal models, and study the underlying biological mechanisms associated with Parkinson's disease in cells taken from people living with the disease.
Parkinson's Disease and Tissue Transplants Essay - For nearly years neural tissue has been transplanted in animals. Transplantation of neural tissue into humans, however, began only a few years ago (1).
It has been found in animals, that fetal brain grafts in damaged adult host brains reduce some of the functional deficits caused by brain. Sawle GV, Bloomfield PM, Bjorklund A, Brooks DJ, Brundin P, Leenders, KL et al.
Transplantation of fetal dopamine neurons in Parkinson's disease: PET [18F]6-l-fluorodopa studies in . Fetal Brain Tissue Transplantation in Parkinson's Disease Patients Essay - Fetal Brain Tissue Transplantation in Parkinson's Disease Patients Parkinson's disease is a neurological disorder characterized initially by muscular rigidity and slowing of voluntary movements (1).
Name of Disorder: Parkinson’s Disease Essay Title: An Introduction to Parkinson’s Disease Authors: Dr Thushara Perera (BE, MBioE, PhD) and Lesioning (careful destruction of brain tissue) is still performed in many medical centres in specific.