Layying off dairy could end up being a good protection against Parkinson’s
Excess levels of the mineral can lead to the formation of ‘toxic clusters’ in the brain – the hallmark of the neurological disorder, say scientists.
The study found calcium links the internal workings of nerve endings and a protein called alpha-synuclein – which is associated with Parkinson’s.
These small membranous structures called synaptic vesicles are vital for communication between brain cells
Large quantities of either calcium or alpha-synuclein could start the chain reaction that leads to the death of neurons, say researchers.
First author Dr Janin Lautenschlager, of Cambridge University, said: “This is the first time we’ve seen calcium influences the way alpha-synuclein interacts with synaptic vesicles.
Parkinson’s disease risks could be increased by an unwanted calcium build-up
When there is too much of one or the other, the balance is tipped and aggregation begins, leading to Parkinson’s disease
“We think alpha-synuclein is almost like a calcium sensor. In the presence of calcium it changes its structure and how it interacts with its environment.”
The researchers said there was no direct link between intake of dairy products or other foods such as fish rich in calcium and Parkinson’s.
Senior author Dr Gabriele Kaminski Schierle, of Cambridge’s Department of Chemical Engineering and Biotechnology, said: “The study relates to the control of intra and extracellular calcium levels which will be the same in any human being independent of its dietary intake.”
The findings, published in the journal Nature Communications, shed fresh light on the causes of Parkinson’s which have baffled scientists for decades.
1 of 9
Famous sufferers include Michael J Fox, Sir Billy Connolly and Neil Diamond who announced last month he was quitting touring after being recently diagnosed.
In 2016 it claimed the life of Muhammad Ali who had battled the debilitating illness for decades.
According to the charity Parkinson’s UK, one in every 350 adults in the UK – an estimated 145,000 in all – currently has the condition, but as yet it remains incurable.
Parkinson’s disease is one of a number of neurodegenerative diseases caused when naturally occurring proteins fold into the wrong shape and stick together with other proteins – eventually forming thin filament-like structures called amyloid fibrils.
These amyloid deposits of aggregated alpha-synuclein, also known as Lewy bodies, are the sign of Parkinson’s.
Billy Connolly is one of many celebrities diagnosed with the life-changing illness
Curiously, it hasn’t been clear until now what alpha-synuclein actually does in the cell – why it’s there and what it’s meant to do.
It’s implicated in various processes such as the smooth flow of chemical signals in the brain and the movement of molecules in and out of nerve endings. But exactly how it behaves is unclear.
Dr Schierle said: “Alpha-synuclein is a very small protein with very little structure, and it needs to interact with other proteins or structures in order to become functional, which has made it difficult to study.”
Thanks to super-resolution microscopy techniques it’s now possible to look inside cells to observe the behaviour of alpha-synuclein.
To do so the researchers isolated synaptic vesicles – part of the nerve cells that store the neurotransmitters which send signals from one nerve cell to another.
In neurons calcium plays a role in the release of neurotransmitters. The researchers observed when calcium levels in the nerve cell increase, such as upon neuronal signalling, the alpha-synuclein binds to synaptic vesicles at multiple points.
This causes the vesicles to come together – indicating the normal role of alpha-synuclein is to help the chemical transmission of information across nerve cells.
Co-first author Dr Amberley Stephens said: “There’s a fine balance of calcium and alpha-synuclein in the cell, and when there is too much of one or the other, the balance is tipped and aggregation begins, leading to Parkinson’s disease.”
Understanding the role of alpha-synuclein in physiological or pathological processes may aid in the development of new treatments for Parkinson’s disease.
One possibility is drugs developed to block calcium, for use in heart disease for instance, might also have potential against Parkinson’s disease.
Medication for Parkinson’s could now include means to block excess calcium
Claire Bale, head of research communications at Parkinson’s UK, said: “We’ve known for some time too much calcium or too much alpha-synuclein – the main protein involved in Parkinson’s – causes problems for brain cells affected in the condition.
“This particular study is interesting because it’s the first time research has shown there may be an important interplay between alpha-synuclein and calcium inside cells, which if disturbed, may cause the damage that ultimately leads to brain cell death.
“Understanding exactly how and why brain cells stop working properly and die in Parkinson’s is still a mystery.
“While more research will need to be done, this important new clue could be the key to better treatments in the future.”