Theories of viral agents as possible causal (or influencing) factors in Parkinson’s have long existed.
This week a research team from Colorado in the USA published a new report demonstrating that mice infected with a mosquito-borne alphavirus (called Western equine encephalitis virus) develop Parkinson’s-like features.
These features include the loss of dopamine neurons, increased neuroinflammation, locomotor issues, and the wide spread presence of aggregated protein (all classical hallmarks of the Parkinsonian brain).
In today’s post, we will look at what mosquito-borne alphaviruses are, what this new study found, and how the results could help us to better understand some cases of Parkinson’s.
Electron micro photograph of Influenza viruses. Source: Neuro-hemin
Between January 1918 and December 1920, there were two terrible outbreaks of an influenza virus.
The event became known as the 1918 flu pandemic.
Approximately 500 million people across the globe were infected by the H1N1 influenza virus during this period, and there were approximately 50 to 100 million associated death.
Now, to put that into perspective for you, that was basically 3-5% of the world’s population at that time.
1918 Spanish flu. Source: Chronicle
At the time, much of the world was blind to these events. Given that this pandemic occurred during World War 1, censors limited the media coverage of the pandemic in many countries in order to try and maintain some sort of morale (very thoughtful of them).
The Spanish media, however, were not censored and this is why the 1918 pandemic is often referred to as the ‘Spanish flu’.
But at the same time that H1N1 influenza virus was causing havoc, a Romanian born neurologist named Constantin von Economo noticed something interesting.
What did he notice?
New data from researchers in Taiwan has intriguing implications for our understanding of the development of Parkinson’s.
An analysis of the enormous national medical database pointed towards towards hepatitis C viral infections as a risk factor for developing Parkinson’s.
But here is the twist in the tale: Interferon-based antiviral therapy reduces that risk back to normal.
In today’s post, we will review the new research, discuss what interferons are, explore what other research has been conducted on interferons in the context of Parkinson’s, and consider the implications of this new research for Parkinson’s.
We have learnt a great deal about Parkinson’s over the last few years via the use of “big data”.
Whether it be the analysis of vast pools of genetic information collected from tens of thousands of individuals with the condition, to analysing massive datasets of longitudinal medical information, these investigations has open new avenues of research and investigation.
For example, “big data” studies have demonstrated that those who smoke cigarettes and drink coffee have a reduced chance of developing Parkinson’s (click here to read a previous SoPD post on this topic). ‘Big data studies have also pointed towards novel therapeutic approaches (click here for a previous SoPD post highighting an example).
Recently, an analysis of medical records from Taiwan have shed new light on another potential influencer of Parkinson’s risk: Hepatitis C
What is Hepatitis C?
With the recent announcement that the STEADY-PD III/Isradipine clinical trial did not reach its primary end point (that of slowing the progression of Parkinson’s), the winds of change have shifted with calls for a focus on biomarkers and better treatments, rather than disease modification.
Recently, researchers at Michigan State University have reported a novel experimental gene thearpy method for dealing with one of the most debilitating aspects of Parkinson’s – dyskinesias.
Ironically, their approach involves the same calcium channels that Isradipine blocks.
In today’s post, we will look at what dyskinesias are, what gene therapy is, and how this new approach could be useful for people currently burdened by these involutary movements.
Dyskinesia. Source: JAMA Neurology
There is a normal course of events following a diagnosis of Parkinson’s.
Yes, I am grossly over-generalising.
And no, I’m not talking from personal experience (this is based on listening to a lot of people), but just go with me on this for the sake of discussion.
First comes the shock of the actual diagnosis. For many it is devastating news – an event that changes the course of their lives. For others, however, the words ‘you have Parkinson’s‘ can provide a strange sense of relief that their current situation has a name and gives them something to focus on.
This initial phase is usually followed by the roller coaster of various emotions (including disbelief, sadness, anger, denial). It depends on each individual.
The emotional rollercoaster. Source: Asklatisha
And then comes the period during which many will try to familiarise themselves with their new situation. They will read books, search online for information, join Facebook groups (Click here for a good one), etc.
That search for information often leads to awareness of some of the realities of the condition.
And one potential reality that causes concern for many people (especially for people with young/early onset Parkinson’s) is dyskinesias.
What are dyskinesias?
Earlier this year, a San Francisco-based biotech company – called Cortexyme – published a research report that grabbed my attention.
The study presented data supporting an alternative theory of the cause of Alzheimer’s – one in which a bacteria involved in gum disease appears to be playing a leading role – and evidence that the company’s lead experimental compound COR388 could have beneficial effects in the treatment of the condition.
While the study was intriguing, what completely blew my mind was the fact that the company had already tested COR388 in a couple of Phase I clinical trials, and since then they have initiated a large Phase II/III trial.
In today’s post, we will discuss this new theory of Alzheimer’s, look at what Cortexyme are doing, and how this could relate to Parkinson’s.
The dashed lines show associations. Source: Slideplayer
Before we start today’s post, a word on ‘associations‘.
Please remember while reading this material that association does not equate to causation.
So if I write something like “researchers have found an association between a type of bacteria that causes gum disease and Alzheimer’s”, it does not mean that someone with either condition necessarily has the other. It only means that they have both simply appeared in the same individuals at a higher than chance rate.
So what is today’s post about?
A very interesting report in which researchers have found an association between a type of bacteria that causes gum disease and Alzheimer’s.
This post is a game of two halves.
The first half will explain the concept of a surgical procedure for Parkinson’s called ‘subthalamic deep brain stimulation‘, in which doctors permenantly implant electrodes into the brain to stimulate a region – the subthalamic nucleus. By stimulating this region with electrical impulses, doctors can provide a better quality of life (in most cases) to people with severe features of Parkinson’s.
In the second half of this post, we will look at an approach to doing the same thing,… but without the electrodes.
Rather, researchers are using gene therapy.
In today’s post, we will discuss what deep brain stimulation is, what gene therapy is, and how the gene therapy approach is having a different kind of impact on the brain to that of deep brain stimulation.
Welcome to the first half of today’s post.
It begins with you asking the question:
What is deep brain stimulation?
Deep brain stimulation (or DBS) is a treatment method that involves embedding electrodes into the brain to help modulate the brain activity involved in movement.
It is a prodcedure that is usually offered to people with Parkinson’s who have excessive tremor or debilitating dyskinesias.
First introduced in 1987, deep brain stimulation consists of three components: the pulse generator, an extension wire, and the leads (which the electrodes are attached to). All of these components are implanted inside the body. The system is turned on, programmed and turned off remotely.
This week a biotech company called Voyager Therapeutics provided an update regarding a gene therapy approach for people with severe Parkinson’s.
Gene therapy is an experimental therapeutic approach that involves inserting new DNA into cells using a virus. The introduced DNA can help a cell to produce proteins that it usually wouldn’t produce, and this can help to alleviate the motor features of Parkinson’s.
In today’s post we will discuss what gene therapy is, what Voyager Therapeutics is trying to do, and outline what their update reported.
There are 4 phases to the clinical trial process of testing new treatment for use in humans:
- Phase I determines if a treatment is safe in humans (this is conducted in an ‘open label’ manner)
- Phase II ‘double blindly’ assesses in a small cohort of subjects if the treatment is effective
- Phase III involves randomly and blindly testing the treatment in a very large cohort of patients
- Phase IV (often called Post Marketing Surveillance Trials) are studies conducted after the treatment has been approved for clinical use
(‘Open label’ refers to both the investigator and the participants in a study knowing what treatment is being administered; while ‘double blind’ testing refers to studies in which the participants and the investigators do not know whether the participant is receiving the active treatment or an inert control treatment until the end of the study).
Based on the successful completion of their Phase I clinical trials for their gene therapy treatment called VY-AADC (Click here to read more about this), Boston-based biotech firm Voyager Therapeutics approached the US Food and Drug Administration (FDA) with the goal of shifting their clinical trial programme into Phase II testing.
What is gene therapy?
Today biotech company Voyager Therapeutics announced an update on their ongoing phase Ib clinical trial. The trial is evaluating the safety and tolerance of a gene therapy approach for people with advanced Parkinson’s.
Gene therapy is a technique that involves inserting new DNA into a cell using viruses. In this clinical trial, the virally delivered DNA helps the infected cell to produce dopamine in order to alleviate the motor features of Parkinson’s.
In today’s post we will discuss what gene therapy is, review the new results mentioned in the update, and look at other gene therapy approaches for Parkinson’s.
Voyager Therapeutics is a clinical-stage gene therapy company that is focused on treatments for neurological conditions, such as Parkinson’s. Today the company announced an update of their ongoing Phase 1b trial of their product VY-AADC01 (Click here to see the press release).
VY-AADC01 represents a new class of treatment for Parkinson’s, as it is a form of gene therapy.
What is gene therapy?
The gene therapy involves introducing a piece of DNA into a cell which will cause the cell to produce proteins that they usually do not (either by nature or by mutation). The DNA is artificially inserted into cells and the cell’s protein producing machinery does the rest.
How does gene therapy work?
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
Last week, as everyone was preparing for Christmas celebrations, researchers at the pharmaceutic company Novartis published new research on a gene that is involved with Parkinson’s, called PARKIN (or PARK2).
They used a new gene editing technology – called CRISPR – to conduct a large screening study to identify proteins that are involved with the activation of PARKIN.
In today’s post we will look at what PARKIN does, review the research report, and discuss how these results could be very beneficial for the Parkinson’s community.
As many people within the Parkinson’s community will be aware, 2017 represented the 200th anniversary of the first report of Parkinson’s disease by James Parkinson.
It also the 20th anniversary of the discovery of first genetic mutation (or variant) that increases the risk of developing Parkinson’s. That genetic variation occurs in a region of DNA (a gene) called ‘alpha synuclein’. Yes, that same alpha synuclein that seems to play such a critical role in Parkinson’s (Click here to read more about the 20th anniversary).
In 2018, we will be observing the 20th anniversary of the second genetic variation associated with Parkinson.
That gene is called PARKIN:
Title: Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism.
Authors: Kitada T, Asakawa S, Hattori N, Matsumine H, Yamamura Y, Minoshima S, Yokochi M, Mizuno Y, Shimizu N
Journal: Nature. 1998 Apr 9; 392(6676):605-8
In 1998, Japanese researchers published this report based on 5 individuals from 4 Japanese families who were affected by juvenile-onset Parkinson’s. In family 1, the affected individual was a female, 43 years old, born of first-cousin parents, and her two younger brothers are healthy. Her condition was diagnosed in her teens and it had then progressed very slowly afterwards. Her response to L-dopa was very positive, but L-dopa-induced dyskinesia were frequent. In family 2-4, affected individuals (born to unrelated parents) exhibited very similar clinical features to the subject in family 1. The age of onset was between 18 to 27 years of age.
Using previous research and various techniques the investigators were able to isolate genetic variations that were shared between the 5 affected individuals. They ultimately narrowed down their search to a section of DNA containing 2,960 base pairs, which encoded a protein of 465 amino acids.
They decided to call that protein PARKIN.
PARKIN Protein. Source: Wikipedia
How much of Parkinson’s is genetic?
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?