The Parkinson’s research community is currently drowning in data related to genetics.
It feels like every time one comes up for air, there is a new study highlighting not one, but half a dozen novel genetic variants associated with an increased risk of developing the condition. This week alone, a new research report has been made available that by itself proposes 39 new genetic risk factors.
The researchers analysed the DNA of 37,700 people with Parkinson’s and 1.4 million (!!!) healthy control subjects and found a total of 92 genetic risk factors for PD.
But what does it all mean? How much influence does genetics have on Parkinson’s?
In today’s post, we will outline the genetics of Parkinson’s, review some of the new studies, and discuss what the new findings mean for Parkinson’s.
When I say the word ‘mutant’, what do you think of?
Perhaps your imagination drifts towards comic book superheroes or characters in movies who have acquired amazing new super powers resulting from their bodies being zapped with toxic gamma-rays or such like.
Alternatively, maybe you think of certain negative connotation associated with the word ‘mutant’. You might associate the word with terms like ‘weirdo’ or ‘oddity’, and think of the ‘freak show’ performers who used to be put on display at the travelling carnivals.
Circus freak show (photo bombing giraffe). Source: Bretlittlehales
In biology, however, the word ‘mutant’ means something utterly different.
What does ‘mutant’ mean in biology?
Each time a cell divides, the DNA inside the resulting pair of cells has changed slightly. These small alterations – known as genetic mutations – provide a method by which an organism can randomly determine traits that may be beneficial.
New research indicates that in certain parts of the brain, post-mitotic (non-dividing) cells are taking on as many as one mutation per week across the span of our lives. This results in thousands of genetic variations accumulating in each cell by the time we eventually pass away in old age.
In today’s post we will review new research and consider what this gradual build up of genetic mutations could mean for our understanding of neurodegenerative conditions, like Parkinson’s.
Coming from the back waters of third world New Zealand, you will understand that sheep hold a very special place in my heart.
I grew up a simple country lad, and each year I had a pet lamb that I would raise and train to do silly tricks in the hope of impressing the judges at the annual agricultural/farm day at school. In addition to instilling me with a crazy fanaticism for the sport (read: religion) of rugby, my parents figured that having a pet lamb each year would teach me a sense of responsibility and a sort of discipline.
I’m not really sure how this practice has influenced my later life, but I certainly do have very fond memories of those early years (the first lamb was named ‘Woolly’, the 2nd lamb was named ‘Woolly2’, the third lamb was actually a goat – bad lambing season – which I named ‘Billy the kid’, the 4th lamb was named ‘MacGyver’,…).
Lots of happy memories.
But as I grew into the teenage years, there was one thing that really bothered me with regards to my pet lambs.
It was that whole negative stigma associated with the ‘black sheep’.
Why, I would wonder, was it the ‘black sheep of the family’ that was the bad kid? And why was the one black sheep in every flock considered the worst of the bunch?
Why was this association applied to sheep?
Why not dogs? Or cows? Why do we pick on sheep?
In 2018, there is one particular clinical trial that I will be watching, because the drug being tested could have a big impact on certain kinds of Parkinson’s.
The clinical trial is focused on people with cancer and they will be treated with a drug called TVB-2640. TVB-2640 is an inhibitor of an enzyme called fatty acid synthase (or FAS).
In today’s post we will discuss why TVB-2640 might be a useful treatment for certain kinds of Parkinson’s.
Mitochondria and their location in the cell. Source: NCBI
Regular readers of this blog are probably getting sick of the picture above.
I use it regularly on this website, because a.) it nicely displays a basic schematic of a mitochondrion (singular), and where mitochondria (plural) reside inside a cell. And b.) a lot of evidence is pointing towards mitochondrial dysfunction in Parkinson’s.
What are mitochondria?
Mitochondria are the power stations of each cell. They help to keep the lights on. Without them, the party is over and the cell dies.
How do they supply the cell with energy?
They convert nutrients from food into Adenosine Triphosphate (or ATP). ATP is the fuel which cells run on. Given their critical role in energy supply, mitochondria are plentiful (some cells have thousands) and highly organised within the cell, being moved around to wherever they are needed.
What does this have to do with Parkinson’s?
New research published in the last week provides further experimental support for numerous clinical trials currently being conducted, including one by the biotech company Sanofi Genzyme.
Researchers have demonstrated that tiny proteins which usually reside on the outer wall of cells could be playing an important role in the protein clustering (or aggregation) that characterises Parkinson’s.
In today’s post we will look at this new research and discuss what it could mean for the on going clinical trials for Parkinson’s.
The proverb ‘When the cat is away, the mice will play’ has Latin origins.
Dum felis dormit, mus gaudet et exsi litantro (or ‘When the cat falls asleep, the mouse rejoices and leaps from the hole’)
It was also used in the early fourteenth century by the French: Ou chat na rat regne (‘Where there is no cat, the rat is king’).
And then Will Shakespeare used it in Henry the Fifth(1599), Act I, Scene II:
Westmoreland, speaking with King Henry V, Gloucester, Bedford, Exeter and Warwick
“But there’s a saying very old and true,
‘If that you will France win,
Then with Scotland first begin:’
For once the eagle England being in prey,
To her unguarded nest the weasel Scot
Comes sneaking and so sucks her princely eggs,
Playing the mouse in absence of the cat,
To tear and havoc more than she can eat”
Interesting. But what does any of this have to do with Parkinson’s?
At the end of each year, it is a useful practise to review the triumphs (and failures) of the past 12 months. It is an exercise of putting everything into perspective.
2017 has been an incredible year for Parkinson’s research.
And while I appreciate that statements like that will not bring much comfort to those living with the condition, it is still important to consider and appreciate what has been achieved over the last 12 months.
In this post, we will try to provide a summary of the Parkinson’s-related research that has taken place in 2017 (Be warned: this is a VERY long post!)
The number of research reports and clinical trial studies per year since 1817
As everyone in the Parkinson’s community is aware, in 2017 we were observing the 200th anniversary of the first description of the condition by James Parkinson (1817). But what a lot of people fail to appreciate is how little research was actually done on the condition during the first 180 years of that period.
The graphs above highlight the number of Parkinson’s-related research reports published (top graph) and the number of clinical study reports published (bottom graph) during each of the last 200 years (according to the online research search engine Pubmed – as determined by searching for the term “Parkinson’s“).
PLEASE NOTE, however, that of the approximately 97,000 “Parkinson’s“-related research reports published during the last 200 years, just under 74,000 of them have been published in the last 20 years.
That means that 3/4 of all the published research on Parkinson’s has been conducted in just the last 2 decades.
And a huge chunk of that (almost 10% – 7321 publications) has been done in 2017 only.
So what happened in 2017? Continue reading
‘Parkinsonisms’ refer to a group of neurological conditions that cause movement features similar to those observed in Parkinson’s disease. They include multiple system atrophy (MSA) and Progressive supranuclear palsy (PSP) and idiopathic Parkinson’s.
Newly published research now shines a light on a possible mechanism for differentiating between multiple system atrophy and idiopathic Parkinson’s.
In today’s post we will look at what multiple system atrophy is, review the new research report, and discuss what these results could mean for the Parkinson’s community.
Brain immaging of multiple system atrophy–related spatial covariance pattern (MSARP) and Parkinson disease–related spatial covariance pattern (PDRP). Source: Neurology
For a long time I have been looking to write a piece of Multiple system atrophy.
I have been contacted by several readers asking for more information about it, and the only thing really delaying me – other than the tsunami of Parkinson’s related research that I am currently trying to write posts for – was the lack of a really interesting piece of research to base the post around.
Guess what came into my inbox yesterday:
Title: Familial Parkinson’s point mutation abolishes multiple system atrophy prion replication.
Authors: Woerman AL, Kazmi SA, Patel S, Aoyagi A, Oehler A, Widjaja K, Mordes DA, Olson SH, Prusiner SB.
Journal: Proc Natl Acad Sci U S A. 2017 Dec 26. pii: 201719369.
This is a really interesting piece of research, that continues a line of other really interesting research.
And if it is independently replicated and verified, it will have massive implications for the Parkinson’s community, particularly those affected by Multiple System Atrophy.
But before we deal with that, let’s start with the obvious question:
What is Multiple System Atrophy?
This week Denali Therapeutics released the results of a phase I clinical trial of their primary product, called DNL-201.
DNL-201 is a LRRK2 inhibitor that the company is attempting to take to the clinic for Parkinson’s disease.
In today’s post we will look at what LRRK2 is, how an inhibitor might help in Parkinson’s, and what the results of the trial actually mean.
Denali. Source: Wikipedia
Denali (Koyukon for “the high one”; also known as Mount McKinley) in Alaska is the highest mountain peak in North America, with a summit elevation of 20,310 feet (6,190 m) above sea level. The first verified ascent to Denali’s summit occurred on June 7, 1913, by four climbers Hudson Stuck, Harry Karstens, Walter Harper, and Robert Tatum.
Tatum (left), Karstens (middle), and Harper (right). Source: Gutenberg
Robert Tatum later commented, “The view from the top of Mount McKinley is like looking out the windows of Heaven!”
More recently another adventurous group associated with ‘Denali’ have been trying to scale lofty heights, but of a completely different sort from the mountaineering kind.
Gene therapy involves treating medical conditions at the level of DNA – that is, altering or enhancing the genetic code inside cells to provide therapeutic benefits rather than simply administering drugs. Usually this approach utilises specially engineered viruses to deliver the new DNA to particular cells in the body.
For Parkinson’s, gene therapy techniques have all involved direct injections of these engineered viruses into the brain – a procedure that requires brain surgery. This year, however, we have seen the EXTREMELY rapid development of a non-invasive approach to gene therapy for neurological condition, which could ultimately see viruses being injected in the arm and then travelling up to the brain where they will infect just the desired population of cells.
Last week, however, this approach hit a rather significant obstacle.
In today’s post, we will have a look at this gene therapy technology and review the new research that may slow down efforts to use this approach to help to cure Parkinson’s.
Gene therapy. Source: rdmag
When you get sick, the usual solution is to visit your doctor.
They will prescribe a medication for you to take, and then all things going well (fingers crossed/knock on wood) you will start to feel better. It is a rather simple and straight forward process, and it has largely worked well for most of us for quite some time.
As the overall population has started to live longer, however, we have begun to see more and more chronic conditions which require long-term treatment regimes. The “long-term” aspect of this means that some people are regularly taking medication as part of their daily lives. In many cases, these medications are taken multiple times per day.
A good example of this is Levodopa (also known as Sinemet or Madopar) which is the most common treatment for the chronic condition of Parkinson’s disease.
When you swallow your Levodopa pill, it is broken down in the gut, absorbed through the wall of the intestines, transported to the brain via our blood system, where it is converted into the chemical dopamine – the chemical that is lost in Parkinson’s disease. This conversion of Levodopa increases the levels of dopamine in your brain, which helps to alleviate the motor issues associated with Parkinson’s disease.
Levodopa. Source: Drugs
This pill form of treating a disease is only a temporary solution though. People with Parkinson’s – like other chronic conditions – need to take multiple tablets of Levodopa every day to keep their motor features under control. And long term this approach can result in other complications, such as Levodopa-induced dyskinesias in the case of Parkinson’s.
Yeah, but is there a better approach?
Here at the SoPD, we regularly talk about the ‘bad boy’ of Parkinson’s disease – a protein called Alpha Synuclein.
Twenty years ago this year, genetic variations were identified in the alpha synuclein gene that increase one’s risk of developing Parkinson’s. In addition, alpha synuclein protein was found to be present in the Lewy bodies that are found in the brains of people with Parkinson’s. Subsequently, alpha synuclein has been widely considered to be the villain in this neurodegenerative condition and it has received a lot of attention from the Parkinson’s research community.
But it is not the only protein that may be playing a role in Parkinson’s.
Today’s post is all about TAU.
I recently informed my wife that I was thinking of converting to Taoism.
She met this declaration with more of a smile than a look of shock. And I was expecting the latter, as shifting from apatheism to any form of religious belief is a bit of a leap you will appreciate.
When asked to explain myself, I suggested to her that I wanted to explore the mindfulness of what was being proposed by Lao Tzu (the supposed author of the Tao Te Ching – the founding document of Taoism).
This answer also drew a smile from her (no doubt she was thinking that Simon has done a bit of homework to make himself sound like he knows what he was talking about).
But I am genuinely curious about Taoism.
Most religions teach a philosophy and dogma which in effect defines a person. Taoism – which dates from the 4th century BCE – flips this concept on its head. It starts by teaching a single idea: The Tao (or “the way”) is indefinable. And then it follows up by suggesting that each person should discover the Tao on their own terms. Given that most people would prefer more concrete definitions in their own lives, I can appreciate that a lot of folks won’t go in for this approach.
Personally speaking, I quite like the idea that the Tao is the only principle and everything else is a just manifestation of it.
According to Taoism, salvation comes from just one source: Following the Tao.
Oh and don’t worry, I’m not going to force any more philosophical mumbo jumbo on you – Taoism is just an idea I am exploring as part of a terribly clichéd middle-life crisis I’m working my way through (my wife’s actual response to all of this was “why can’t you just be normal and go buy a motor bike or something?”).
My reason for sharing this, however, is that this introduction provides a convenient segway to what we are actually going to talk about in this post.
You see, some Parkinson’s researchers are thinking that salvation from neurodegenerative conditions like Parkinson’s will come from just one source: Following the TAU.
What is TAU?
Genetic mutations (or ‘variants’) in the Leucine-rich repeat kinase 2 (or LRRK2; also known as Dardarin) gene are associated with increased risk of Parkinson’s. As a result this gene has become the focus of a lot of genetic research.
But what about LRRK2’s less well-known, rather neglected sibling LRRK1?
In today’s post, we will look at new research that suggests the LRRK siblings could both be involved with Parkinson’s disease.
I recommend to the reader that today’s post should be read with the following music playing in the background:
Inspired by a poem of the same title, English composer Ralph Vaughan Williams wrote ‘The Lark Ascending’ in 1914. It is still to this day, a tune that remains a firm favourite with BBC listeners here in the UK (Source).
On to business:
While the music and the poem are about a songbird, today’s SoPD post deals with a different kind of Lark.
Or should I say LRRK.
This is Sergey Brin.
He was one of the founders of a small company you may have heard of – it’s called “Google”.
Having changed the way the world searches the internet, he is now turning his attention to other projects.
One of those other projects is close to our hearts: Parkinson’s disease.