So where does Parkinson’s begin? Some say the brain, others say it starts in the gut, but who is right? Considering that Parkinson’s is considered a whole-body disease, the starting point can be ambiguous. Researchers and medical professionals are taking a look at whether Parkinson’s disease may not be brain-first after all. What is now being considered are the early “prodromal” symptoms, changes in the body that take place years before the first signs of the disease actually appear, and it just might start in your gut. Does the disease start in your digestive system and then travel upwards?
The Gut Microbiome
Your digestive system contains trillions of microorganisms, including bacteria, viruses, and fungi, with thousands of different species that have their own functions, and millions of microbial genes that outnumber the amount of DNA you carry. These are independent to the point that they almost act like a separate organ in your body. They have an enormous task working with your immune system, metabolism, and nervous system to keep the body functioning. Some of the primary responsibilities include breaking down food that your body can’t digest on its own, producing certain vitamins like B and K, and producing fatty acids that help protect the brain and the gut itself. Other duties these bacteria are responsible for are training your immune system, helping regulate blood sugar, and energy use by influencing how your body stores fuel. It also helps support brain chemistry by helping to produce serotonin (a chemical primarily made in the gut to help promote well-being, sleep, and emotional resilience), dopamine precursors (an amino acid called Tyrosine produced from foods like dairy, beans, nuts, fish, and meat), and other signaling molecules, and talks directly to your brain by using your body’s nerves, hormones and immune signals.
For healthy people, this factory we carry around helps keep the body regulated and working, but for people with Parkinson’s disease, an unhealthy microbiome offers an array of physical and mental problems Parkinson’s patients are well familiar with because of an altered gut microbiome. There have been studies that have shown lower amounts of good bacteria, lower abundance of beneficial, short-chain fatty acid-producing bacteria, weaker intestinal barriers known as “leaky gut”, and higher rates of altered bacterial patterns that have been linked to disease progression and symptoms.
The Alpha-Synuclein Connection
The hallmark of Parkinson’s disease is the misfolded protein alpha-synuclein, or a-Syn. These are spaghetti-like proteins that, in the brain, twist and clump together instead of folding into place. As these “piles” of proteins twist and start clumping, they go toxic, interfere with normal cell function, form aggregates known as Lewy bodies, and gradually kill off dopamine-producing neurons. Dopamine isn’t just our reward center; it regulates things like movement, thinking, motivation, willpower, and influences our mood. The questions researchers are trying to answer are where does alpha-synuclein begin, is it brain first or gut first?
A researcher named Heiko Braak was the first to propose that Parkinson’s disease may start outside the brain. According to Braak, a-Syn appears in the gut, smell centers, and the lower brain stem, which could be responsible for symptoms like constipation, loss of smell, and troubles with sleep, which could surface years before Parkinson’s disease is diagnosed. What Braak proposes, though, is that a-Syn travels up the Vagus nerve (think of it as the information super highway between the gut and the brain) and into the brain stem and spreads through the brain’s connected networks.
Braak’s hypothesis turned out to be a starting point for ongoing research and opened up new avenues of how Parkinson’s disease spreads throughout the body. Also, it’s not a one-size-fits-all scenario for every patient; Parkinson’s is different for everyone based on the disease’s starting point, the brain’s network, environmental exposures, and gut health.
So There are Two
As it stands now, there seems to be a consensus among researchers, neurologists, and clinicians that there are two models of Parkinson’s based on the emerging evidence: brain first, symptoms that start in the nose/brain with early signs of loss of smell and tremor, and body first: the disease starts in the gut with constipation and sleep problems. These differences help explain why Parkinson’s looks so different from person to person, and why treatments that help one patient may not help another.
There’s another thought going around with the community that Parkinson’s disease could be many different subtypes of the same disease that can begin in different parts of the body, causing different symptoms, and progress at different rates of speed.
The trend in research pointing to Parkinson’s as a whole-body disease comes together, and why a call is being made to change the way Parkinson’s trials are conducted using more advanced tools, longer testing periods, and matching individuals to trials they are most suited for.
This is Why a Healthy Diet is Important
Regardless of whether you have Parkinson’s disease or not, more research has been shown that the Gut Microbiome is a crucial part of overall health, and keeping those bacteria on track is crucial. KetoFlex diets and holistic medicine, consisting of more plant-rich foods and exercise, go a long way to help restore the Gut Microbiome and keep the ecosystem healthy. Many neurologists encourage patients to select organic foods and stick to a Mediterranean diet that is rich in fruits, vegetables, whole grains, legumes, olive oil, and lean proteins. These foods support beneficial bacteria in the gut and boost brain health.
There is no cure for Parkinson’s (yet), with the changing landscape of research and artificial intelligence, the connection between the microbiome and the brain is paramount to overall health, for everyone.
All media made by Chris Denny/ChatGPT
