Last week there was a press release from La Trobe University in Melbourne, Australia regarding the development of a new blood test for Parkinson’s disease. The announcement is a little bit odd as the results of the study are still being peer-reviewed (press announcements usually come after the publication of results). But the Parkinson’s community is excited by the idea of new diagnostic aids, especially those that can maybe tell us something new about the disease.
In this post, we will review what we know at present, and we will follow up this post once the results are eventually published.
As we have previously written, the diagnosis of Parkinson’s is rather difficult, with a 10-15% error rate becoming apparent when brains are analysed at the postmortem stage. Thus any new diagnostic tools/tests that can aid in this effort would be greatly appreciated.
A group at La Trobe University in Melbourne have been studying the blood of people with neurodegenerative conditions, and have now announced that they may have a blood test for Parkinson’s disease.
The La Trobe University team: (left to right) Professor Paul Fisher, Dr Sarah Annesley and Dr Danuta Loesch-Mdzewska. Source: La trobe
So what do we know thus far?
The test has been conducted on blood taken from a total of 38 people (29 people with Parkinson’s disease and 9 in a control group). Professor Paul Fisher – one of the lead scientists in the study – has reported that the tests have proven ‘very reliable’.
What does the test measure?
The test is apparently looking at the mitochondria in the blood cells.
And what are mitochondria?
A mitochondrion (singular) is a small structure inside a cell that is responsible for respiration and energy production. It is one of the powerhouses of the cell. Cells have lots of mitochondria (plural) because cells need lots of energy. But when the mitochondria start failing, the cell dies. As the mitochondria fails, they send out toxic chemical signals that tell the cell to begin shutting down.
A schematic of a mitochondria, and where they are inside a cell. Source: Shmoop
The researchers at La Trobe found in their blood tests that there was no damage to the mitochondria of patients with Parkinson’s disease. That in itself is an interesting observation, but what they found next has larger implications:
“Based on the current literature we were expecting reduced oxygen consumption in the mitochondria, which leads to a buildup of toxic byproducts, but what we saw was the exact opposite,” Prof Fisher was quoted as saying. “We were able to show the mitochondria were perfectly normal but were working four times as hard, which also leads to increased production of poisonous byproducts to occur.”
A test that can measure these ‘hyperactive’ mitochondria is very useful as it can both identify people with Parkinson’s disease, but it may also help us to better understand the condition. Prof Fisher and his colleagues, in addition to taking the test forward, are also trying to understand the underlying mechanisms of the ‘hyperactive mitochondria’ – what is causing them to become the way they are.
What is going to happen now?
The scientists at La Trobe would like to repeat and expand on the results (after they are published), and the Michael J Fox foundation and Shake It Up Australia have given La Trobe University more than $640,000 to further develop the research. The plan is to now test 100 subjects – 70 people with Parkinson’s disease and a control group of 30. Prof Fisher is hoping that a test may be available for the clinic in five years time.
What about other neurodegenerative conditions?
So here’s the catch with the information provided thus far – the researchers have not had the funding to test whether this hyperactivity in the mitochondria is occurring exclusively in people with Parkinson’s. That is to say, they haven’t tested whether the effect is also present in people with other neurodegenerative diseases, such as Alzheimer’s, Huntington’s, or ALS. And this is where a little bit of the excitement comes out of the announcement.
But even if the hyperactivity in the mitochondria is shared between certain neurodegenerative diseases, a test highlighting the effect would still be very useful, especially if it can aid us in early detection of these conditions.
As we said above, we will be following this story closely and will report back here as and when information becomes available.