Related Experiment Video
Updated: Jun 7, 2026
09:27
Sequential Extraction of Soluble and Insoluble Alpha-Synuclein from Parkinsonian Brains
Published on: January 5, 2016
The decrease of β-synuclein in cortical brain areas defines a molecular subgroup of dementia with Lewy bodies
Katrin Beyer1, Montserrat Domingo-Sàbat, Cristina Santos
1Servicio de Anatomía Patológica, Hospital Universitario Germans Trias i Pujol, Universidad Autonoma de Barcelona, Barcelona, Spain. katrinbeyer@hotmail.com
Brain : a Journal of Neurology
|October 21, 2010
Summary
A significant decrease in beta-synuclein expression was found in dementia with Lewy bodies patients. This suggests a distinct molecular subtype of dementia with Lewy bodies, impacting Lewy body disease understanding.
Area of Science:
- Neuroscience
- Molecular Biology
- Pathology
Background:
- Lewy body diseases, including dementia with Lewy bodies (DLB) and Parkinson's disease (PD), share identical pathological features despite distinct clinical presentations.
- Alpha-synuclein (α-synuclein) aggregation is central to Lewy body disease pathogenesis.
- Beta-synuclein (β-synuclein) is known to inhibit α-synuclein aggregation and interact with it.
Purpose of the Study:
- To analyze the expression of β-synuclein and α-synuclein transcripts in brain samples from patients with different Lewy body disease pathologies and controls.
- To investigate the correlation between β-synuclein expression, clinical phenotype, and neuropathological diagnosis.
- To identify potential molecular subtypes of dementia with Lewy bodies.
Main Methods:
- Real-time polymerase chain reaction (PCR) was used to determine relative messenger RNA (mRNA) expression levels of β-synuclein and α-synuclein (SNCA140).
- Expression changes were quantified using the ΔΔC(t) method.
- Messenger RNA expression data were validated at the protein level.
Main Results:
- A drastic reduction in β-synuclein expression was observed in cortical areas of patients with pure diffuse Lewy body pathology and the DLB clinical phenotype.
- This diminished β-synuclein expression was not observed in cases with concomitant Alzheimer's disease pathology or the Parkinson's disease with dementia phenotype.
- Expression data correlated with clinical and neuropathological diagnoses, suggesting a specific molecular subtype of DLB.
Conclusions:
- A significant decrease in cortical β-synuclein expression characterizes a specific molecular subtype of dementia with Lewy bodies.
- These findings offer new insights into the pathogenesis of Lewy body diseases.
- Understanding these molecular mechanisms is crucial for comprehending complex neurodegenerative disorders.
Related Concept Videos
01:22Dementia l: Introduction
Dementia is an acquired, progressive syndrome characterized by a decline in multiple cognitive domains severe enough to impair daily functioning and reduce independence. Although memory loss is a central feature, the diagnosis requires additional deficits involving language, executive function, visuospatial skills, judgment, calculation, or abstract reasoning. These cognitive impairments reflect underlying neurodegenerative or vascular processes that gradually disrupt neuronal networks...
01:37Neural Regulation
Digestion begins with a cephalic phase that prepares the digestive system to receive food. When our brain processes visual or olfactory information about food, it triggers impulses in the cranial nerves innervating the salivary glands and stomach to prepare for food.
01:23Alzheimer Disease ll: Pathophysiology
Alzheimer disease involves structural changes in the brain that begin long before symptoms appear. The most distinctive features are extracellular neuritic plaques and intracellular neurofibrillary tangles.Neuritic plaques form in the cerebral cortex and around blood vessels. These plaques contain a dense core of beta-amyloid (Aβ)—a toxic protein fragment that clumps outside neurons. The core is surrounded by damaged neuronal extensions, as well as reactive astrocytes and microglia. Abnormal...
01:24Parkinson Disease ll: Pathophysiology
Parkinson disease (PD) is a progressive neurodegenerative disorder primarily affecting movement, with additional non-motor features. Its pathophysiology involves complex interactions among genetic susceptibility, environmental exposures, and cellular dysfunction, including dopaminergic neuron loss, protein aggregation, and mitochondrial impairment.Selective NeurodegenerationA key feature is the degeneration of dopaminergic neurons in the substantia nigra pars compacta, leading to reduced...
01:30Dementia
Dementia is a collective term for cognitive disorders primarily affecting memory, thinking, and reasoning. It is not a specific disease but a syndrome, with Alzheimer's disease being the most common cause, accounting for approximately 60-80% of cases. Other types include vascular dementia, Lewy body dementia, and frontotemporal dementia. Dementia affects millions worldwide, particularly older adults, though it is not a normal part of aging.
The progression of dementia is generally gradual.
The progression of dementia is generally gradual.
01:24Parkinson Disease l: Introduction
Parkinson’s disease is a chronic, progressive neurodegenerative disorder that primarily affects movement. It is characterized by motor symptoms such as resting tremors, muscle rigidity, bradykinesia (slowness of movement), and postural instability. Patients may notice hand tremors at rest, stiffness during movement, or a shuffling gait. In addition to motor features, non-motor symptoms include sleep disturbances, mood and behavioral changes, constipation, and cognitive impairment, all of which...