Parkinson's disease is a growing neurodegenerative condition and, despite decades of intensive research, there is still no reliable drug or diagnostic test. However, with the help of a woman with a particularly strong smell, scientists have discovered how Parkinson's changes human smell. They hope that this discovery can help to make an early diagnosis.
Currently, treatment cannot start until motor symptoms such as tremor and stiffness appear. However, nervous tissue analysis starts around 6 years before people notice any clinical signs. Finding a reliable way of diagnosing Parkinson's disease would mean that the treatment could start earlier and keep the condition in the bay.
Doctors have used the smell as a diagnostic tool for centuries. For example, some people claim that smelling scopulosis is like musty beer, while abdominal typhoid causes a smell that reminds people of baking bread. Until recently, there was no odor associated with a neurodegenerative condition of any kind.
Joy Milne can understand Parkinson's disease
Joy Milne belongs to people who are oppressive to smell and can distinguish them very effectively. In 1986, doctors diagnosed Parkinson's husband and since then Joy has been able to distinguish between the specific smells associated with the disease.
Recently, a group of researchers have joined Joy Milne to try to differentiate between what chemicals can cause to this particular smell. The findings have recently been published in a journal ACS Central Science.
First, the researchers needed to decide where the smell was coming from. It was noticed that she was the most intense on her upper back and her forehead, but not in her armpit. This means that the smell is probably not of sweat, but from sebum that produces sebaceous glands in the skin.
Scientists already know that there is an increase in sebum production, called seborrhea, in Parkinson's disease. Scientists led by Perdita Barran tried to understand which chemicals sebum could cause a change in odor.
He therefore collected samples of sebum from the upper back of 60 individuals. Some people have Parkinson's disease and some do not.
Using mass spectrometry, scientists analyzed sebum samples to identify any chemicals that had been raised in people with Parkinson's disease. They have shown that there is a significant difference between volatile chemicals in people with Parkinson's disease and healthy people. In the event, three compounds play a key role in a particular smell: hippuric acid, eicosanic acid and octadecanal.
Importantly, there were no significant differences between people with Parkinson's, whether they were taking medicines or not. This means that the change in smell is probably not due to treatment. Having given these chemicals to Joy Milne, he was able to identify the "troubled" smell of Parkinson's disease.
Scientists have conducted this study with a limited number of participants, so they will have to continue with their work. However, they hope that this can be a unique way of detecting Parkinson's disease much sooner than it is currently possible.
Why do smells change?
Researchers have not planned their study to find out why the three levels of these compounds in the serum are high in people with Parkinson's disease. However, the authors discuss some possible cases.
For example, earlier studies have confirmed that there are links between different skin conditions and Parkinson's disease. These include, for example, Malassezia spp.
According to the authors of the study these changes in yeast and bacterial populations can alter the microflora and physiology of the skin through “highly specific” methods for Parkinson's disease.
These findings open up new possibilities for Parkinson's disease and can also give a new insight into how this condition is developing.