Us Parkies are often told that it’s best to keep active – both physically and mentally. I’ve read of older Parkies who make a point of completing fiendishly difficult crosswords as part of this drive to mental activity.
Might this be part of the reason? It’s a New Scientist article, the gist of which is that there are immune cells within the brain whose function appears to be – from recent research – to consume idle brain cells. The immune cells, known as microglia, were previously understood to “clean up brain debris”, in the words of Beth Stevens, one of the researchers. Now, it transpires that the debris tidied up includes unused brain cells in healthy brains as well as damaged cells in brains affected by disease. Apparently, a chemical known, prosaically, as C3 is used to mark synapses for destruction.
The quote that inspired my illustration was also Stevens’:
“We think C3 is an ‘eat me’ signal,” says Stevens.
The researchers studied mice engineered to have one eye more active than the other; postmortem examination revealed that microglia had removed the synapses (connections) from the underactive eye-brain circuit. To my mind, this is an ingeniously simple means of investigating the matter, but I suspect that it may also be too simple (and too restrictive) to draw any firm conclusions from.
The research paper’s abstract can be read here (New Scientist’s link seems to be broken at the time of writing). However, be prepared for a significant level of specialist language. Something tells me that Ms. Stevens, with her way wwith words, may not have written the abstract.
Note: Neither the New Scientist news article nor the abstract say anything about Parkinson’s. I am not sure that this procedure (microglia tidying up unused brain cells) is likely to be a cause of Parkinson’s (which is due to the loss of a very specific type of brain cell). However, once you do have a diagnosis of Parkinson’s, it’s worth trying to conserve what is left…
It occurs to be to wonder, however, whether it might be possible to link this story with the anecdotal “Parkinson’s Personality”. The suggestion there is that, pre-diagnosis and, by inference, pre-onset, those who will go on to develop Parkinson’s are the quieter, less daring, less ambitious types… the ones who don’t make an awful lot of use of their dopamine. I should stress that this is no more than an idle thought of mine (obviously some of the connections in my brain are still functional!) and that I am not aware of any research that backs this idea up. Over to you – what do you think?