Bacteria found in milk triggers rheumatoid arthritis
A bacteria found in milk can trigger rheumatoid arthritis in genetically predisposed people, new research suggests. Rheumatoid arthritis is an inflammatory disease that affects more than 1.3 million adults, the majority of whom are women, in the United States alone.
Crohn’s disease is also an inflammatory disease, and the Crohn’s Disease and Colitis Foundation says it affects up to 780,000 adults in the US alone.
What do these two diseases have in common, besides being characterized by inflammation? A lot, in fact, according to new research recently published in the journal Frontiers in Cellular and Infection Microbiology .
Both conditions share a similar genetic origin and are often treated with similar immunosuppressants, because both diseases are autoimmune disorders.
These similarities intrigued the authors of the new research, who are: Saleh Naser, an infectious disease specialist at the University of Central Florida (UCF) in Orlando, and Dr. Shazia Bég, who is a rheumatologist in medical practice at UCF and Robert Sharp, who is a Ph.D. Biomedical Science Candidate at UCF School of Medicine.
“Here,” says Naser, “you have two inflammatory diseases, one affects the gut and the other affects the joints, and they both share the same genetic defect and are treated with the same medications. Do they have a common trigger? That was the question we posed and he set out to investigate. ”
In previous research, Naser had already discovered a link between the bacterium Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn’s disease, so the question of whether MAP was also related in any way to rheumatoid arthritis naturally followed.
In fact, Naser is currently involved in a clinical trial investigating whether Crohn’s disease can be treated with antibiotics or not. Therefore, if this bacterium is also present in rheumatoid arthritis, this condition can also be treated with antibiotics specifically designed for this bacterium.
Genetic mutation plus bacteria means higher risk
The researchers analyzed clinical samples from 100 people with rheumatoid arthritis. Of these, 78 percent had a genetic mutation that they shared with people with Crohn’s disease: the PTPN2 / 22 gene.
Of the people with rheumatoid arthritis with this gene mutation, 40 percent also had MAP.
“We believe that people who are born with this genetic mutation and who are then exposed to MAP through consumption of contaminated milk or meat from infected cattle are at increased risk of developing rheumatoid arthritis.”
“We do not know the cause of rheumatoid arthritis, so we are excited that we found this association,” says Bég. “But there is still a long way to go.”
Directions for future research
“We need to find out,” say the authors, “why this bacterium is more prevalent in these patients, whether it is present because they have RA (rheumatoid arthritis) or whether it causes RA in these patients.” If we find out, then we can target the MAP bacteria. ”
To this end, the researchers plan to conduct further studies, in the hope that their findings will be replicated.
National studies should now also investigate how many patients get rheumatoid arthritis and Crohn’s disease, scientists say. They themselves plan to further examine the association in people from different countries and of different ethnicities.
“Understanding the role of this bacterium in rheumatoid arthritis, ” explains Naser, “means that the disease could be treated more effectively. Ultimately, we can administer a combination treatment to attack both inflammation and bacterial infection. ”