A happy and healthy stomach requires a balanced diet and healthy nutrition. A healthy stomach allows healthy bacteria to flourish while at the same time protecting the stomach from bad bacteria and food-borne illness. Many factors are at play in the stomach to ensure proper health. A recent study, which was published in PLOS Pathogen, identified a key protein that is involved in maintaining the delicate balance that helps to create an ideal environment within the stomach.
The study revolved around the SIGIRR (Single Ig IL-1-related receptor) protein, which is protein that is found in humans on the surface of the cells that line the stomach. The SIGIRR protein dampens the natural (innate) response of these cells to bacteria. Previous research has shown that the SIGIRR protein helps to modulate immune response, colonic epithelial homeostasis and tumorigenesis. Xiaoxia Li from the Lerner Research Institute in Cleveland and Bruce Vallance from British Columbia’s Childrens’ Hospital and the University of British Columbia were the lead researchers for the current study.
Mice that were missing the SIGIRR gene were infected with either Salmonella Typhimurium or E.Coli which are both known pathogens that cause food poisoning in rodents. The researchers found that these mice had a stronger natural intestinal immune response to the bacterial pathogens than mice that had normal SIGIRR protein functioning. However, they were not able to defend against these bacterial pathogens, which ultimately resulted in sickness – a much worse reaction than the mice with normal SIGIRR protein functioning. The researchers concluded that normal SIGIRR protein functioning is essential to protect the stomach from bacterial pathogens that can cause serious food poisoning and bowel inflammation.
Colonization resistance is the process by which beneficial bacteria help to protect the stomach from invading pathogens by competing for space and nutrients. The heightened natural immune response seen when SIGIRR isn’t functioning properly results in diminished beneficial bacteria in the stomach. The result is that the beneficial bacteria in the stomach are unable to compete with the invading toxic bacteria, leaving the stomach susceptible to these pathogens, often resulting in sickness.
It is believed that normal SIGIRR functioning is necessary to maintain a delicate balance within the stomach, providing protection from invading pathogens. While the innate immune response is compromised with normal SIGIRR functioning, the healthy bacteria found in the stomach are protected. This helps to perform a protective barrier against invading toxic pathogens through the process of colonization resistance.
The results from the current study may help individuals suffering with stomach disorders, such as inflammatory bowel disease. Future research should investigate potential treatment options using the SIGIRR protein. Developing treatments that modify SIGIRR functioning may help to create a well-environment within the stomach in affected individuals, helping to alleviate the disturbing and often embarrassing symptoms that are associated with many stomach conditions.