Understanding rare diseases is integral in treating them. In order to do so, research into the underlying causes and factors behind these conditions is needed. A recent study published in Cell did just this.
In fact, this study identified a protein, called TMEM106B, that acts as a commonality between a number of neurodegenerative disorders, such as progressive supranuclear palsy (PSP), frontotemporal dementia (FTD), and Lewy body dementia (LBD). This new link will hopefully lead to further research that could then produce treatment and intervention options.
About the Study
Led by Anthony W.P. Fitzpatrick, PhD, and 22 other researchers, this study was conducted at Columbia University. They utilized the brains of 11 patients who had lived with one of the three neurodegenerative disorders in question, using cryo-electron microscopy in order to closely study the fine details of the brain tissue.
This is how they discovered the TMEM106B protein, which lives in between the membranes of endosomes and lysosomes. Upon, further analysis, they discovered that this protein was capable of forming fibrils. This finding led them to theorize that these fibrils impact the lysosomes, making them unable to perform their job and clean the waste from the cells.
Further research is necessary, but these findings are extremely helpful in directing said research. If you want to read more about them, head here.
About the Neurodegenerative Disorders
PSP is a brain disorder that damages the nuclei, causing progressive issues with movement. It affects approximately three to six of every 100,000 people, although this number could be higher due to the number of people who are misdiagnosed with Parkinson’s. This is because the symptoms of the two conditions are similar. PSP effects include issues with balance and walking, falling, sleep disturbances, changes in personality and judgment, stiffness, issues with eye movement, slowed movement, alterations in mood and behavior, speech issues, eating and swallowing problems, and depression.
The exact cause of this disorder is unknown, but medical professionals do know that progressive damage to nerve cells in the brain stem is a part of it. In rare cases, PSP is inherited from parents due to a mutated MAPT gene. In order to obtain a diagnosis, doctors will look for the characteristic symptoms, perform a clinical evaluation, look at patient history, perform MRIs, and use PET scans. Treatment is symptomatic.
Acting as the second most common form of dementia, LBD is characterized by a progressive decline in mental ability. Symptoms worsen over time and include:
- Visual hallucinations
- Note: Olfactory, auditory, and tactile hallucinations are also possible
- Fluctuating attention (e.g., staring into space for long periods, episodes of drowsiness, long naps)
- Movement disorders
- Note: these can be Parkinson-like in nature
- Sleep difficulties
- Cognitive issues
- Note: these can be Alzheimer’s-like in nature
- Poorly regulated autonomic nervous system
- This can cause symptoms like bowel issues, dizziness, orthostatic hypotension, falls, and loss of bladder control
- Behavioral changes
After about seven to eight years post-onset, LBD is typically fatal. It is the result of Lewy bodies that build up and form masses in the brain.
According to the Mayo Clinic, FTD is an umbrella term for a number of conditions impacting the brain’s frontal and temporal lobes. Specifically, these lobes atrophy, causing symptoms like extreme behavioral and personality changes, motor disorders and related symptoms, and problems with speech and language. Medical professionals are not exactly sure as to why these symptoms occur or the frontal and temporal lobes shrink. Further research – like that conducted by Anthony W.P. Fitzpatrick, PhD, and his team – is necessary to gain a better understanding of FTD.