Parkinson disease

Parkinsons (PD) research on α-Synuclein
with the new matrix ProPhyl Air

What is Parkinson’s disease?

Parkinson’s disease (PD) is movement disorder of the nervous system that worsens over time. As nerve cells (neurons) in parts of the brain weaken or are damaged or die, people may begin to notice problems with movement, tremor, stiffness in the limbs or the trunk of the body, or impaired balance. As these symptoms become more obvious, people may have difficulty walking, talking, or completing other simple tasks. Not everyone with one or more of these symptoms has PD, as the symptoms appear in other diseases as well.

No cure for PD exists today, but research is ongoing and medications or surgery can often provide substantial improvement with motor symptoms.

What causes the disease?

 



Protein aggregates have been observed in the nerve tissue of patients with Parkinson’s disease which consist of induvidual components (monomers) of  the protein alpha-synuclein. These assemble into what are referred to as amyloid fibrils. Similar deposits are also found in the case of other neurodegenerative diseases such as Alzheimer’s. Researchers are looking for approaches to prevent fibril formation and potentially cure the diseases.

 



Aggregates of amyloid proteins characterize many neurodegenerative disorders including Alzheimer’s disease (AD) and Parkinson’s disease (PD). Formation of pathological inclusions occurs by a multistep process including the misfolding of normal soluble proteins and their association into higher order oligomers, followed by their assembly into amyloid fibrils (figure 5) that form disease specific inclusions. 

 

figure 1

The formation of intermediate  fibril aggregation shown in the fig. 1 left could be an indication that one or more of misfolding
isoforms of the α-synuclein shown in the IEF (fig. 2) could be the cause of the production of macromolecular amyolid fibrils the leads to Parkinson’s.

Fig.1 left
Sample A,B,C,D

α-Synuclein in different aggregation stages of fibril production (intermediate fibrils). 
Sample C + D
Large amounts of insoluble aggregated fibrils can be found on the application point (below).
Causally responsible for Parkinson’s disease. Probably caused by degenerative synuclein
The size of the fibrils can be well over 2mD.

Sample S
monomeric α-Synuclein

Fig.1 right
Sample A,B,C,D,S
previously unknown proteins in the high pH range (> pH 8,5)

Samples:
H. Lundbeck A/S
Ottiliavej 9
2500 Valby/Copenhagen
Denmark

Human α-synuclein after electrophoretic IEF separation.
At least six α-synuclein bands of unknown origin

figure 3

Sample A,B,C,D
α-Synuclein in different stages of fibril aggregation (intermediate fibrils). 
Sample hu-α-Synuclein
Human monomeric synuclein checked with FPLC and SDS electrophoresis (figure 2+4). Several bands were identified in the IEF with ProPhyl Air that could result from the protein fragmentation into subunits. This finding is new and needs further investigation.

figure 4

monomere α-Synuclein checked with SDS electrophoresis

α-synuclein is expressed principally in the nervous system, but it is also produced in the other tissues, including the skin. In the brain, the protein is primarily neuronal, but it is also present in glia. Neuronal α-synuclein is concentrated in the presynaptic nerve terminals, interacts with plasma membrane phospholipids, and is also present in the nuclei and mitochondria. At least  six synuclein bands of unknown origin (fig. 2). The most common isoform is a 140 amino acid-long transcript. Other isoforms are α-synuclein-126, lacking residues 41-54; and α-synuclein-112, which lacks residues 103-130. α-synuclein’s physiological role is poorly understood, but the protein has been implicated in regulating dopamine release and transport, synaptic vesicle clustering, and functioning as a SNARE-complex chaperone.


α-Synuclein fibrils are a major component of the intracellular Lewy bodies that are associated with Parkinson’s disease, Lewy body dementia, and multiple system atrophy (see below)

α-Synuclein fibrils are a major component of the intracellular Lewy bodies that are associated with Parkinson's disease, Lewy body dementia, and multiple system atrophy (see below)

figure 5

Precipitated fibril aggregation stained
with Coomassie on an IEF gel.
Because of the size > 2mD
Gel electrophoresis is not possible

figure 6

ProPhyl Air made a decisive contribution to the discovery of α-Synuclein in cerebrospinal fluid using the isoelectric focusing method