Recently a really interesting research report was published that presented several rather amazing findings.
The researchers forced dopamine-producing cells in a rodent brain to start making a protein called neuromelanin and by doing this, they witnessed the occurence of Parkinson’s-like features (motor issues, Lewy body-like structures, and cell death).
The report also suggested a method by which this outcome could be reduced or rescued.
But the amazing part is that neuromelanin was previously considered to be protective and this new finding suggests we may need to rethink that idea.
In today’s post, we will discuss what neuromelanin is, what this new report found, and how this new knowledge could be useful in the context of Parkinson’s.
Prof Heiko Braak. Source – Memim.com
This is Prof Heiko Braak.
Many years ago, he sat down and examined hundreds of postmortem brains from people with Parkinson’s.
He had collected brains from people who passed away at different stages of the condition, and was looking for any kind of pattern that might explain where and how the disease starts. His research led to what is referred to as the “Braak staging” model of Parkinson’s – a six step explanation of how the condition spreads up from the brain stem (the top of the spinal cord) and into the rest of the brain (Click here and here to read more about this).
The Braak stages of PD. Source: Nature
Braak found that certain populations of cells in the brain were more vulnerable to Parkinson’s than others, such as the dopamine neurons in a region called the substantia nigra, the noradrenergic neurons of the locus coeruleus, and the neurons of the dorsal motor nucleus of the vagus (don’t worry about what any of those names actually mean, I’m just trying to sound smart and make you think that I know what I’m taking about).
One feature that all of these populations of neurons all share in common – in addition to vulnerability to Parkinson’s – is the production of pigment called neuromelanin.
What is neuromelanin?
It is often said that Parkinson’s is a ‘distinctly human’ condition. Researchers will write in their reports that other animals do not naturally develop the features of the condition, even at late stages of life.
But how true is this statement?
Recently, some research has been published which brings into question this idea.
In today’s post, we will review these new findings and discuss how they may provide us with a means of testing both novel disease modifying therapies AND our very notion of what Parkinson’s means.
Checking his Tinder account? Source: LSE
Deep philosphical question: What makes humans unique?
Seriously, what differentiates us from other members of the animal kingdom?
Some researchers suggest that our tendency to wear clothes is a uniquely human trait.
The clothes we wear make us distinct. Source: Si-ta
But this is certainly not specific to us. While humans dress up to ‘stand out’ in a crowd, there are many species of animals that dress up to hide themselves from both predator and prey.
A good example of this is the ‘decorator crab’ (Naxia tumida; common name Little seaweed crab). These creatures spend a great deal of time dressing up, by sticking stuff (think plants and even some sedentary animals) to their exoskeleton in order to better blend into their environment. Here is a good example:
Many different kinds of insects also dress themselves up, such as Chrysopidae larva:
Dressed for success. Source: Bogleech
In fact, for most of the examples that people propose for “human unique” traits (for example, syntax, art, empathy), mother nature provides many counters (Humpback whales, bower birds, chickens – respectively).
So why is it that we think Parkinson’s is any different?
Wait a minute. Are there other animals that get Parkinson’s?
In the 1990, scientists identified some fruits that they suspected could give people Parkinson’s.
These fruit are bad, they reported.
More recently, researchers have identified chemicals in that exist in those same fruits that could potential be used to treat Parkinson’s.
These fruit are good, they announce.
In today’s post, we will explain why you should avoid eating certain members of the Annonaceae plant family and we will also look at the stream of research those plants have given rise to which could provide a novel therapy for Parkinson’s.
Guadeloupe. Source: Bluefoottravel
In the late 1990s, researchers noticed something really odd in the French West Indies.
It had a very strange distribution of Parkinsonisms.
What are Parkinsonisms?
‘Parkinsonisms’ refer to a group of neurological conditions that cause movement features similar to those observed in Parkinson’s disease, such as tremors, slow movement and stiffness. The name ‘Parkinsonisms’ is often used as an umbrella term that covers Parkinson’s disease and all of the other ‘Parkinsonisms’.
Parkinsonisms are generally divided into three groups:
- Classical idiopathic Parkinson’s disease (the spontaneous form of the condition)
- Atypical Parkinson’s (such as multiple system atrophy (MSA) and Progressive supranuclear palsy (PSP))
- Secondary Parkinson’s (which can be brought on by mini strokes (aka Vascular Parkinson’s), drugs, head trauma, etc)
Some forms of Parkinsonisms that at associated with genetic risk factors, such as juvenile onset Parkinson’s, are considered atypical. But as our understanding of the genetics risk factors increases, we may find that an increasing number of idiopathic Parkinson’s cases have an underlying genetic component (especially where there is a long family history of the condition) which could alter the structure of our list of Parkinsonisms.
So what was happening in the French West Indies?
Nuclear receptor related 1 protein (or NURR1) is a protein that is critical to the development and survival of dopamine neurons – the cells in the brain that are affected in Parkinson’s disease.
Given the importance of this protein for the survival of these cells, a lot of research has been conducted on finding activators of NURR1.
In today’s post we will look at this research, discuss the results, and consider issues with regards to using these activators in Parkinson’s disease.
Comet Hale–Bopp. Source: Physics.smu.edu
Back in 1997, 10 days after Comet Hale–Bopp passed perihelion (April 1, 1997 – no joke; perihelion being the the point in the orbit of a comet when it is nearest to the sun) and just two days before golfer Tiger Woods won his first Masters Tournament, some researchers in Stockholm (Sweden) published the results of a study that would have a major impact on our understanding of how to keep dopamine neurons alive.
Dopamine neurons are one group of cells in the brain that are severely affected by Parkinson’s disease. By the time a person begins to exhibit the movement symptoms of the condition, they will have lost 40-60% of the dopamine neurons in a region called the substantia nigra. In the image below, there are two sections of brain – cut on a horizontal plane through the midbrain at the level of the substantia nigra – one displaying a normal compliment of dopamine neurons and the other from a person who passed away with Parkinson’s demonstrating a reduction in this cell population.
The dark pigmented dopamine neurons in the substantia nigra are reduced in the Parkinson’s disease brain (right). Source:Memorangapp
The researchers in Sweden had made an amazing discovery – they had identified a single gene that was critical to the survival of dopamine neurons. When they artificially mutated the section of DNA where this gene lives – an action which resulted in no protein for this gene being produced – they generated genetically engineered mice with no dopamine neurons:
Title: Dopamine neuron agenesis in Nurr1-deficient mice
Authors: Zetterström RH, Solomin L, Jansson L, Hoffer BJ, Olson L, Perlmann T.
Journal: Science. 1997 Apr 11;276(5310):248-50.
The researchers who conducted this study found that the mice with no NURR1 protein exhibited very little movement and did not survive long after birth. And this result was very quickly replicated by other research groups (Click here and here to see examples)
So what was this amazing gene called?
The protein Alpha Synuclein has long been considered the bad-boy of Parkinson’s disease research. Possibly one of the main villains in the whole scheme of things.
New research suggests that it may be interfering with a neuroprotective pathway, leaving the affected cell more vulnerable to stress/toxins. But that same research has highlighted a novel beneficial feature of an old class of drugs: MAO-B inhibitors.
In today’s post we will outline the new research, discuss the results, and look at whether this new Trk warrants a re-think of MAO-B inhibitors.
The great Harry Houdini. Source: Wikipedia
I’m not sure about you, but I enjoy a good magic trick.
That exhilarating moment when you are left wondering just one thing: How do they do that?
(Seriously, at 4:40 a baguette comes out of thin air – how did he do that?)
Widely believed to have been one of the greatest magicians of all time (Source), Harry Houdini is still to this day revered among those who practise the ‘dark arts’.
Born Erik Weisz in Budapest (in 1874), Houdini arrived in the US in 1878. Fascinated with magic, in 1894, he launched his career as a professional magician and drew attention for his daring feats of escape. He renamed himself “Harry Houdini” – the first name being derived from his childhood nickname, “Ehrie,” and the last name paying homage to the great French magician Jean Eugène Robert-Houdin. In 1899, Houdini’s act caught the eye of Martin Beck, an entertainment manager, and from there the rest is history. Constantly upping the ante, his feats became bolder and more death defying.
And the crowds loved him.
From stage, he moved on to film – ultimately starting his own production company, Houdini Picture Corporation. In addition, he was a passionate debunker of psychics and mediums, his training in magic helping him to expose frauds (which turned him against his former friend Sir Arthur Conan Doyle, who believed deeply in spiritualism).
This is all very interesting, but what does any of it have to do with Parkinson’s?