A reader recently asked me about an experimental drug called Ibudilast.
It is a ‘Phosphodiesterase 4 inhibitor’.
Recently there was a very interesting result in a clinical trial looking at Ibudilast in a specific neurodegenerative condition. Sadly for the reader that condition was not Parkinson’s, in fact very little research has been done on Ibudilast in Parkinson’s
In today’s post we will look at what Phosphodiesterase inhibitors are, how they work, and discuss why Ibudilast may not be such a good experimental treatment for Parkinson’s.
On April 21-27th, 2018, the American Academy of Neurology (AAN) will hold their 70th Annual Meeting in Los Angeles (California).
I will not be at the meeting, but I will definitely be keeping an eye out for any news regarding the results of one particular clinical trial. At the meeting, a biopharmaceutical company called MediciNova Inc. will be presenting data regarding one of their clinical trials.
The presentation, entitled “Ibudilast – Phosphodiesterase Type 4 Inhibitor – Bi-Modal Therapy with Riluzole in Early Cohort and Advanced Amyotrophic Lateral Sclerosis (ALS) Patients – Final Report and Future Directions“ (Source) will be presented by principal investigator of the clinical study, Dr. Benjamin Rix Brooks, of the Carolinas HealthCare System’s Neuromuscular/ALS-MDA Center at Carolinas HealthCare System Neurosciences Institute.
Dr Brooks will be presenting the results of a single-center, randomized, double-blind, placebo-controlled clnical trial which was conducted to evaluate the safety, tolerability and clinical endpoint responsiveness of a drug called Ibudilast (or MN-166) in subjects with the neurodegenerative condition, Amyotrophic Lateral Sclerosis (or ALS – also known as motor neuron disease; Click here to read a previous SoPD post about ALS and Click here to learn more about this clinical trial).
What is Ibudilast?
Ibudilast is a phosphodiesterase inhibitor.
What is a phosphodiesterase inhibitor?
There has been a lot of discussion on this site (and elsewhere on the web) regarding the need for more objective systems of measuring Parkinson’s – particularly in the setting of clinical trials.
Yes, subjective reports of patient experience are important, but they can easily be biased by ‘placebo responses’.
Thus, measures that are beyond the clinical trial participants conscious control – and focused on biological outcomes – are needed.
In today’s post, we will consider one possible approach: Smart pills. We will discuss what they are, how they work, and how they could be applied to Parkinson’s research.
In order to encourage a growing discussion regarding objective measures of Parkinson’s (and to follow up on previous rants – Click here and here for examples), I have decided to regularly (once a month) highlight new technologies that could provide the sort of unbiased methods of data collection that are required for assessing whether a treatment is having an impact on Parkinson’s.
Today, we will look at smart pills.
What is a smart pill?
This is one of those post (read: rants) where I want to put an idea out into the ether for someone to chew on. It starts with a very simple question:
Why is ‘the drug’ the focus of a clinical trial?
If our goal is to find beneficial therapies for people with Parkinson’s, then the way we currently clinically test drugs is utterly nonsensical.
And if we do not change our “we’ve always done it this way” mindset, then we are simply going to repeat the mistakes of the past. Others are changing, so why aren’t we?
In today’s post, we will consider one possible alternative approach.
Why is ‘the drug‘ the focus of a clinical trial?
The way we clinically test drugs makes absolutely no sense when you actually stop and think about it.
Other medical disciplines (such as oncology) have woken up to this fact, and it is time for the field of Parkinson’s research to do this same.
Let me explain:
My piece was called the Dilemma of Success, and it explored a hypothetical situation that we may very well face in the not-so-distant future.
Optimistic as I am about the future of Parkinson’s research, I think this is a very serious issue – one which the Parkinson’s community needs to discuss and start planning for. I am re-posting it here today as I am keen for some thoughts/discussion on this matter.
Lord Robert Baden-Powell. Source: Utahscouts
My scout master looked around the horse shoe, making eye contact with each of us, before asking a simple question:
“When did Noah build the ark?”
My fellow scouts and I looked at each other. Some of us were wondering if the guy had completely lost the plot and somehow thought that it was Sunday morning and he was doing the sermon. Others seriously looked like they were trying to calculate an exact date.
He waited a moment for one of us to offer up some idiotic attempt at an answer, before he solemnly said:
“Before the rain”
It’s one of those childhood moments that didn’t make sense at the time, but comes back to haunt you whenever you can foresee certain troubles coming over the hill towards you.
The dilemma of success
It will be nice to have this problem, but it will still be a problem.
And we need to plan for it
Recently I was invited to speak at the 6th Annual East Midlands Parkinson’s Research Support Network meeting at the Link Hotel, in Loughborough. The group is organised and run by the local Parkinson’s community and supported by Parkinson’s UK. It was a fantastic event and I was very grateful to the organisers for the invitation.
They kindly gave me two sessions (20 minutes each) which I divided into two talks: “Where we are now with Parkinson’s research?” and “Where we are going with Parkinson’s research?”. Since giving the talk, I have been asked by several attendees if I could make the slides available.
The slides from the first talk can be found by clicking here.
I have also made a video of the first talk with a commentary that I added afterwards. But be warned: my delivery of this second version of the talk is a bit dry. Apologies. It has none of my usual dynamic charm or energetic charisma. Who knew that talking into a dictaphone could leave one sounding so flat.
Anyways, here is the talk – enjoy!
I hope you find it interesting. When I have time I’ll post the second talk.
We have previously discussed the powerful antioxidant Resveratrol, and reviewed the research suggesting that it could be beneficial in the context of Parkinson’s disease (Click here to read that post).
I have subsequently been asked by several readers to provide a critique of the Parkinson’s-associated research focused on Resveratrol’s twin sister, Pterostilbene (pronounced ‘Terra-still-bean’).
But quite frankly, I can’t.
Why? Because there is NO peer-reviewed scientific research on Pterostilbene in models of Parkinson’s disease.
In today’s post we will look at what Pterostilbene is, what is known about it, and why we should seriously consider doing some research on this compound (and its cousin Piceatannol) in the context of Parkinson’s disease.
Blue berries are the best natural source of Pterostilbene. Source: Pennington
So this is likely to be the shortest post in SoPD history.
Because there is nothing to talk about.
There is simply no Parkinson’s-related research on the topic of today’s post: Pterostilbene. And that is actually a crying shame, because it is a very interesting compound.
What is Pterostilbene?
Like Resveratrol, Pterostilbene is a stilbenoid.
Stilbenoids are a large class of compounds that share the basic chemical structure of C6-C2-C6:
Resveratrol is a good example of a stilbenoid. Source: Wikipedia
Stilbenoids are phytoalexins (think: plant antibiotics) produced naturally by numerous plants. They are small compounds that become active when the plant is under attack by pathogens, such as bacteria or fungi. Thus, their function is generally considered to part of an anti-microbial/anti-bacterial plant defence system for plants.
The most well-known stilbenoid is resveratrol which grabbed the attention of the research community in a 1997 study when it was found to inhibit tumour growth in particular animal models of cancer:
In a recent post, I discussed research looking at foods that can influence the progression of Parkinson’s (see that post here). I am regularly asked about the topic of food and will endeavour to highlight more research along this line in future post.
In accordance with that statement, today we are going to discuss Cruciferous vegetables, and why we need a clinical trial of broccoli.
I’m not kidding.
There is growing research that a key component of broccoli and other cruciferous vegetables – called Glucoraphanin – could have beneficial effects on Parkinson’s disease. In today’s post, we will discuss what Glucoraphanin is, look at the research that has been conducted and consider why a clinical trial of broccoli would be a good thing for Parkinson’s disease.
Cruciferous vegetables. Source: Diagnosisdiet
Like most kids, when I was young I hated broccoli.
Man, I hated it. With such a passion!
Usually they were boiled or steamed to the point at which they have little or no nutritional value, and they largely became mush upon contact with my fork.
The stuff of my childhood nightmares. Source: Modernpaleo
As I have matured (my wife might debate that statement), my opinion has changed and I have come to appreciate broccoli. Our relationship has definitely improved.
In fact, I have developed a deep appreciation for all cruciferous vegetables.
And yeah, I know what you are going to ask:
What are cruciferous vegetables?
Cruciferous vegetables are vegetables of the Brassicaceae family (also called Cruciferae). They are a family of flowering plants commonly known as the mustards, the crucifers, or simply the cabbage family. They include cauliflower, cabbage, garden cress, bok choy, broccoli, brussels sprouts and similar green leaf vegetables.
Cruciferous vegetables. Source: Thetherapyshare
So what have Cruciferous vegetables got to do with Parkinson’s?
Well, it’s not the vegetables as such that are important. Rather, it is a particular chemical that this family of plants share – called Glucoraphanin – that is key.
What is Glucoraphanin?
The motor features of Parkinson’s disease can be managed with treatments that replace the chemical dopamine in the brain.
While there are many medically approved dopamine replacement drugs available for people affected by Parkinson’s disease, there also are more natural sources.
In today’s post we will look at the science and discuss the research supporting one of the most potent natural source for dopamine replacement treatment: Mucuna pruriens
When asked by colleagues and friends what is my ‘plan B’ (that is, if the career in academia does not play out – which is highly probable I might add – Click here to read more about the disastrous state of biomedical research careers), I answer that I have often considered throwing it all in and setting up a not-for-profit, non-governmental organisation to grow plantations of a tropical legume in strategic places around the world, which would provide the third-world with a cheap source of levodopa – the main treatment in the fight against Parkinson’s disease.
Plan B: A legume plantation. Source: Tropicalforages
The response to my answer is generally one of silent wonder – that is: me silently wondering if they think I’m crazy, and them silently wondering what on earth I’m talking about.
As romantic as the concept sounds, there is an element of truth to my Plan B idea.
I have read many news stories and journal articles about the lack of treatment options for those people with Parkinson’s disease living in the developing world.
Hospital facilities in the rural Africa. Source: ParkinsonsLife
Some of the research articles on this topic provide a terribly stark image of the contrast between people suffering from Parkinson’s disease in the developing world versus the modernised world. A fantastic example of this research is the work being done by the dedicated researchers at the Parkinson Institute in Milan (Italy), who have been conducting the “Parkinson’s disease in Africa collaboration project”.
The researchers at the Parkinson Institute in Milan. Source: Parkinson Institute
The project is an assessment of the socio-demographic, epidemiological, clinical features and genetic causes of Parkinson’s disease in people attending the neurology out-patients clinic of the Korle Bu Teaching and Comboni hospitals. Their work has resulted in several really interesting research reports, such as this one:
Title: The modern pre-levodopa era of Parkinson’s disease: insights into motor complications from sub-Saharan Africa.
Authors: Cilia R, Akpalu A, Sarfo FS, Cham M, Amboni M, Cereda E, Fabbri M, Adjei P, Akassi J, Bonetti A, Pezzoli G.
Journal: Brain. 2014 Oct;137(Pt 10):2731-42.
PMID: 25034897 (This article is OPEN ACCESS if you would like to read it)
In this study, the researchers collected data in Ghana between December 2008 and November 2012, and each subject was followed-up for at least 6 months after the initiation of Levodopa therapy. In total, 91 Ghanaians were diagnosed with Parkinson’s disease (58 males, average age at onset 60 ± 11 years), and they were compared to 2282 Italian people with Parkinson’s disease who were recruited during the same period. In long-term follow up, 32 Ghanaians with Parkinson’s disease were assessed (with an average follow period of 2.6 years).
There are some interesting details in the results of the study, such as:
- Although Levodopa therapy was generally delayed – due to availability and affordability – in Ghana (average disease duration before Levodopa treatment was 4.2 years in Ghana versus just 2.4 years in Italy), the actual disease duration – as determined by the occurrence of motor fluctuations and the onset of dyskinesias – was similar in the two populations.
- The motor fluctuations were similar in the two populations, with a slightly lower risk of dyskinesias in Ghanaians.
- Levodopa daily doses were higher in Italians, but this difference was no longer significant after adjusting for body weight.
- Ghanaian Parkinson’s sufferers who developed dyskinesias were younger at onset than those who did not.
Reading these sorts of research reports, I am often left baffled by the modern business world’s approach to medicine. I am also left wondering how an individual’s experience of Parkinson’s disease in some of these developing nations would be improved if a cheap alternative to the dopamine replacement therapies was available.
Are any cheap alternatives available?
Dopamine agonist treatments are associated with approximately 90% of hyper-sexuality and compulsive gambling cases that occur in people with Parkinson’s disease.
This issue does not affect everyone being treated with this class of drugs, but it is a problem that keeps popping up, with extremely damaging consequences for the affected people who gamble away their life’s saving or ruin their marriages/family life.
The U.S. Food and Drug Administration (FDA) is yet to issue proper warning for this well recognised side-effect of dopamine agonists, and yet last week they gave clearance for the clinical testing of a new implantable device that will offer continuous delivery of dopamine agonist medication.
In today’s post, we will discuss what dopamine agonists are, the research regarding the impulsive behaviour associated with them, and why the healthcare regulators should acknowledge that there is a problem.
Dopamine. Source: Wikimedia
Before we start talking about dopamine agonists, let’s start at the very beginning:
What is dopamine?
By the time a person is sitting in front of a neurologist and being told that they ‘have Parkinson’s disease’, they will have lost half the dopamine producing cells in an area of the brain called the midbrain.
Dopamine is a chemical is the brain that plays a role in many basic functions of the brain, such as motor co-ordination, reward, and memory. It works as a signalling molecule (or a neurotransmitter) – a way for brain cells to communicate with each other. Dopamine is released from brain cells that produce this chemical (not all brain cells do this), and it binds to target cells, initiating biological processes within those cells.
Dopamine being released by one cell and binding to receptors on another. Source: Truelibido
Dopamine binds to target cells via five different receptors – that is to say, dopamine is released from one cell and can bind to one of five different receptors on the target cell (depending on which receptor is present). The receptor is analogous to a lock and dopamine is the key. When dopamine binds to a particular receptor it will allow something to happen in that cell. And this is how information from a dopamine neuron is passed or transmitted on to another cell.
Dopamine acts like a key. Source: JourneywithParkinsons
This is Lysimachos.
Pronounced: “Leasing ma horse (without the R)” – his words not mine.
He is one of the founders of an Edinburgh-based biotech company called “Parkure“.
In today’s post, we’ll have a look at what the company is doing and what it could mean for Parkinson’s disease.
The first thing I asked Dr Lysimachos Zografos when we met was: “Are you crazy?”
Understand that I did not mean the question in a negative or offensive manner. I asked it in the same way people ask if Elon Musk is crazy for starting a company with the goal of ‘colonising Mars’.
In 2014, Lysimachos left a nice job in academic research to start a small biotech firm that would use flies to screen for drugs that could be used to treat Parkinson’s disease. An interesting idea, right? But a rather incredible undertaking when you consider the enormous resources of the competition: big pharmaceutical companies. No matter which way you look at this, it has the makings of a real David versus Goliath story.
But also understand this: when I asked him that question, there was a strong element of jealousy in my voice.
Incorporated in October 2014, this University of Edinburgh spin-out company has already had an interesting story. Here at the SoPD, we have been following their activities with interest for some time, and decided to write this post to make readers aware of them.