A research team has discovered that a microbe found in the gut can contribute to certain symptoms of Parkinson’s disease. In mice predisposed to Parkinson’s, transplanted gut microbes from human patients with the disease caused motor deficits to worsen. The details are in a paper that was just published in the journal Cell.
Parkinson’s disease is a chronic central nervous system disorder with no cure. Tremors are often an early indication of the disease and symptoms progress to loss of balance, body stiffness, slurred speech, and movement problems. Although the disease continues to worsen, there are medications and other treatments that can help manage symptoms. Treatments for the motor deficits have side effects and tend to stop working after a while. This has led researchers to search for alternative treatments and potential cures.
Researchers led by a scientist from the California Institute of Technology investigated a possible link between gut microbiota and Parkinson’s disease. The gut contains a number of beneficial microbes, including bacteria that aid in digestion and the immune response. There are even studies that show links between gut microbiota and mood swings. Not every gut microbe is beneficial, however, and some have the potential to be harmful.
The team started their experiment by raising two groups of mice. One group contained mutations that made them predisposed to developing Parkinson’s disease. The control group consisted of normal, healthy mice. The mice were raised in sterile conditions. The researchers then took samples of gut microbes from human Parkinson’s patients and transplanted the bacteria into the guts of the mice.
The mice that were predisposed to Parkinson’s disease developed even worse motor problems after the microbe transplant. The healthy mice showed no signs of change. This shows that certain gut microbes may worsen Parkinson’s disease symptoms. The research team then treated the mice with antibiotics designed to reduce the number of these gut bacteria. The mice with Parkinson’s showed immediate improvement and motor problems were reduced.
The team’s findings show that gut microbes may contribute to certain symptoms of Parkinson’s disease. Mice that were later treated with antibiotics showed significant improvement. The authors believe this is a major step toward fully understanding Parkinson’s disease and developing effective treatments.
Sampson et al. Gut Microbiota Regulate Motor Deficits and Neuroinflammation in a Model of Parkinson’s Disease. Cell (2016).