The Role of the Gut Microbiome
The elusive gut microbiome constitutes a complex biological environment of 100 trillion microorganisms, called the gut flora, found in the large intestinal wall. Compromised of diverse bacteria, viruses, archaea, and fungi - all of which which aid in maintaining the intestinal integrity of the protective mucosal barrier to protecting against pathogens. Further, the gut flora hosts immunomodulation by activating T-cells and cytokines in response to invading pathogens that cause infection. This highly individualistic relationship forms with the gut flora and gastrointestinal tract, and contributes greatly to the host's gut function and general well-being.
Mechanisms of Intestinal Disease
However, when the microbiota is abnormal in count or microbial diversity, dysbiosis or microbial imbalance occurs and can lead to adverse and unhealthy changes in the gut physiology. Recent evidence suggests that the onset of gastrointestinal diseases such as Crohn's and Ulcerative Colitis, are significantly contributed to dysregulated gut flora. An uncontrolled immune response is triggered in which negatively modifies the healthy and harmonious microbiome. The consequences of this include the diminishing of beneficial gut bacteria's, thinning of the protective mucosal intestinal wall, and an uncontrolled exchange of microbes between the wall layers. As a result, chronic inflammation occurs and other symptoms such as fatigue, diarrhea, weight loss, and fever can begin. This evidence suggests that microbial dysbiosis and its intricate cellular responses, are a prominent contributing factor in the onset and worsening of intestinal disease.
Public Health Implications
The incidence of Crohn's and Ulcerative Colitis is rising dramatically worldwide, namely in western societies, and is projected to affect up to 30 million individuals by the year 2025. Current therapies are targeted at purely the biological component of disease, and it is managed by immune suppression. Research suggests the importance of including environmental factors like microbiota, in understanding the full spectrum of disease causing agents. Hope lies in the development of new treatments that target the microbiota and barrier function.
Sources:
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Vindigni, S. M., Zisman, T. L., Suskind, D. L., & Damman, C. J. (2016). The intestinal microbiome, barrier function, and immune system in inflammatory bowel disease: a tripartite pathophysiological circuit with implications for new therapeutic directions. Therapeutic advances in gastroenterology, 9(4), 606–625. https://doi.org/10.1177/1756283X16644242
Wallace, K. L., Zheng, L. B., Kanazawa, Y., & Shih, D. Q. (2014). Immunopathology of inflammatory bowel disease. World journal of gastroenterology, 20(1), 6–21. https://doi.org/10.3748/wjg.v20.i1.6 Assessed and Endorsed by the MedReport Medical Review Board