Role of stomach microbiota in health and disease :
Bacteria in the digestive tract can contribute to and be affected by the disease in various ways. The
presence or enrichment of some kinds of bacteria may lead to inflammatory disorders such
as inflammatory bowel disease. Additionally, metabolites from certain members of the gut flora
may impact host signaling pathways, leading to disorders such as obesity and cancer. Following are
the diseases caused by microbiota present in the gastrointestinal tract:
- Inflammatory bowel disease:
The term inflammatory bowel disease (IBD) is a group of disorders in which the intestines become
inflamed. It has often been believed as an autoimmune disease, but recent studies propose that
chronic inflammation may not be due to the immune system attacking the body itself. Instead,
it is a result of the immune system attacking a harmless virus, bacteria, or food in the gut,
that causes inflammation that leads to bowel injury.
- Cancer
Some genera of bacteria, such as Bactericides and Clostridium, are associated with an increase
in tumor growth rate, while other genera, such as Lactobacillus and Bifidobacteria, are known to
prevent tumor formation. Stomach cancer can be treated with surgery, radiation therapy, or
immunotherapy.
- Liver disease
As the liver is directly linked to the portal vein so any microorganisms that cross the intestinal
epithelium and the intestinal mucosal barrier enter the liver, and as a result cytokines release.
Dysbiosis in the gut flora has been associated with the development of cirrhosis and non-alcoholic
fatty liver disease.
- Obesity and metabolic syndrome.
The gut and gut microbiota promote metabolic inflammation and disorder, which are important
signs of metabolic diseases such as obesity. Low-grade inflammation is characteristic of obesity.
Researchers have discovered a new link between gut bacteria and obesity. They found that certain
amino acids in our blood can be connected to both obesity and the composition of
the gut microbiome. It affects our metabolism and can be linked to obesity, cardiovascular disease,
and type 2 diabetes.
- Ulcers
Helicobacter pylori can cause stomach ulcers by crossing the epithelial lining of the stomach. Here
the body produces an immune response. During this response, parietal cells are activated and
release extra hydrochloric acid (HCl+) into the stomach. However, the response does not stimulate
the mucus-secreting cells that protect and line the epithelium of the stomach. The extra acid
produce holes into the epithelial lining of the stomach, resulting in stomach ulcer.
