- Scientists found that gastro-intestinal problems that
included constipation were present before neurological symptoms were
expressed in Parkinson's patients.
- Study on gut microbes showed that gut microbes
influenced motor deficits in mice prone to Parkinson's.
- Probiotic therapy and antibiotic therapy have been
found to aid in lowering motor deficits in mice prone to Parkinson's.
Researchers have found
that gut microbes
play a crucial role in
Parkinson's like movement disorder in mice that are genetically compromised.
The study published in the Journal Cell
found that antibiotic therapy
eliminated movement deficits and molecular hallmarks that were found in
Parkinson's like disease in mice.
The study findings highlight the
influence of gut microbes on Parkinson's disease, which is the second most
common neurodegenerative disease in the U.S.
‘Probiotic therapy could improve a healthy group of gut bacteria and lower risk for hallmark Parkinsonís symptoms.’
Dr. Sarkis Mazmanian of
the California Institute of Technology who is the senior author of the study
spoke about the significance of the study, "We have discovered for the first
time a biological link between the gut microbiome and Parkinson's disease. More
generally, this research reveals that a neurodegenerative disease may have its
origins in the gut, and not only in the brain as had been previously thought.
The author further added saying "The discovery that changes in the
microbiome may be involved in Parkinson's disease is a paradigm shift and opens
entirely new possibilities for treating patients."
Scientists have thus far
been studying changes in the brain and possible causative factors in patients
with this neurodegenerative disorder, however, this is the first time that gut
microbes have been studied with an effect on Parkinson's disease.
- This condition was first described in 1817 by James
Parkinson, a British physician who called the condition "the shaking
- It belongs to a group of diseases called movement disorders
- One million people in the U.S are found to be affected
by this disease
- India has the lowest incidence of Parkinson's, 70 in
- The Parsi community has one of the highest incidences
of Parkinson's with an incidence of 328 in 100,000.
- The condition results in the loss of nerve cells,
especially in the region substantia nigra, in the brain.
The most characteristic
symptom associated with Parkinson's is tremors, which is the involuntary
movement of the extremities.
Other symptoms include
stiffness of the muscles, slow movement and an impairment of the gait.
Gut Microbes as a Possible Source
Lead author Mazmanian,
along with Timothy Sampson of the California Institute of Technology studied
Parkinson's in an attempt to identify possible causes for the condition. The
starting point of the current research was gastro-intestinal problems like
constipation that occurs in patients with Parkinson's even before the start of
motor symptoms. This was due to changes in the gut microbiome of these individuals.
Gut microbiomes have been previously studied and have been implicated in
autism, anxiety, depression and cognitive ability but this is the first study
that examined gut microbes in Parkinson's disease.
Effect of Gut Microbes
The researchers grew genetically modified
mice (mice that were prone to acquiring a disease similar to Parkinson's)
either in a normal cage which was not sterile or in a cage that was germ free.
- The mice that grew in the germ-free environment showed
lower deficits in motor activity and there was less accumulation of
misfolded protein present in regions of the brain that were involved in
motor ability. Moreover, these mice showed normal activity like removing
adhesive from the nose, crossing a beam and going down a pole.
- Antibiotic treatment given to mice which grew in a
normal environment resulted in a similar reduction in motor deficits.
- Mice that were grown in cages that were germ-free and
which were treated with fecal transplants of gut microbes from mice that
were grown in normal environment showed worst motor symptoms.
These results were used
to determine that gut microbe had a significant effect on motor ability in mice
that were predisposed to Parkinson's.
Gut Microbes and Genes
The scientists concluded
that gut microbes worked along with genes that resulted in Parkinson's. When
mice that were genetically modified to be prone to motor deficits were treated
with fecal transplants, there was an exacerbation of the symptoms. While mice
that were genetically normal did not show any change on fecal transplants from
a patient with Parkinson's.
, according to the researchers,
will aid in alleviating the symptoms associated with the condition. They also
found that fecal transplants and antibiotics might not be viable forms of
treatment at this stage.
cautioned "Long-term, high-strength antibiotic use, like we utilized in this
study, comes with significant risk to humans, such as defects in immune and
metabolic function. Gut bacteria provide immense physiological benefit, and we
do not yet have the data to know which particular species are problematic or
beneficial in Parkinson's disease."
researchers at this stage are focusing on identifying bacteria that offer
protection and isolating bacteria that could trigger motor deficits.
Mazmanian further added
that "Much like any other drug discovery process, translating this
innovative work from mice to humans will take many years. But this is an
important first step toward our long-term goal of leveraging the deep,
mechanistic insights that we have uncovered for a gut-brain connection to help
ease the medical, economic, and social burden of Parkinson's disease."
Gut microbes are
becoming increasingly important. The presence of gut microbes improves our
digestive process and their presence was thought to protect the body from
attachment by harmful micro-organisms.
However recent advances
have shown that gut microbes could increase the risk for rheumatoid
, eye diseases antiphospholipid
and a host of other infections.
Such studies bring to
the fore the importance of maintaining 'good' gut bacteria by consuming
probiotic yogurt on a regular basis.
- What is Parkinson's Disease? - (http://www.pdf.org/about_pd)