Utility of gut flora in pathogenesis of diseases with special reference to rheumatoid arthritis

Gut flora, or gut microbiota, or gastrointestinal microbiota, is the complex community of microorganisms that live in the digestive tracts of humans and other animals, including gut immune cells. These gut immune cells are important gatekeepers. They must detect and destroy foreign invaders that ride on the food we eat. However, the gut’s immune system has to reach a delicate balance between fighting invaders and allowing nutrients to enter the body. If the immune system is too lax, we get infected. If it is too aggressive, we get allergic reactions and possibly autoimmune diseases. Rheumatoid arthritis is a chronic disease that causes painful swelling in the joints. The disease usually starts in the hands and feet and works its way toward central joints over time. Without effective treatment, rheumatoid arthritis can cause severe deformity and disability. Currently, the most effective treatments for rheumatoid arthritis are drugs that suppress the immune system. Patients who first develop rheumatoid arthritis have a substantially lower number of helpful bacteria in their gastrointestinal systems. People with rheumatoid arthritis have significantly less Bifidobacteria, Bacteroides-Porphyromonas-Prevotella species, Bacteroides fragilis species and the Eubacterium rectale-Clostridium coccoides species. Despite intense research, scientists still do not know exactly what causes rheumatoid arthritis. However, evidence now strongly suggests that the number and types of bacteria present in the gastrointestinal tract influences the development of rheumatoid arthritis. Prevotella copri may be a bacterial trigger of rheumatoid arthritis. Likewise, patients with early rheumatoid arthritis seem to have abnormally low amounts of many helpful bacterial species.Thus the gut microbiota plays a vital role in pathogenesis as well as recovery of gut microbiota.