The gut microbiome is vital to supporting fundamental, nutritional, metabolic, and immune system mechanisms—which is why it's so important to ensure that it's kept healthy, protected, and balanced, in order to carry out these roles as effectively as possible.¹

Gut microbiota—at the intersection of everything? Patrice D. Cani, Nature Reviews Gastroenterology & Hepatology, 2017

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It is quite normal for the average gut to have a tremendous number of microbial consortia living symbiotically, specifically including:²

The gastrointestinal tract plays host to more than one thousand species of bacteria, which are actually beneficial. A gut that contains a diverse array of bacteria has been shown to be more stable and resilient to, for example, infection—so diversity of bacteria is known to be an indicator of a healthy gut.³

However, research has demonstrated that the composition of the gut microbiome is not static, and can alter according to changes in diet,⁴ stress,⁵ or amount and quality of sleep.⁶

 

What Does the Gut Microbiome Do in the Body?

The gut microbiome plays a key role in a number of functions that help to sustain a healthy body:

 

Metabolism

• Fermenting non-digestible food components (mainly dietary fiber) to produce short-chain fatty acids that help maintain a healthy colon.³
• Synthesizing of essential nutrients, such as B vitamins.⁴
• Release/stimulation of neurotransmitters, e.g. dopamine and serotonin.⁵

Immunity

• Gut-associated lymphoid tissue is highly specialized and is the main entity of mucosal-associated lymphoid tissue, representing ~70% of the entire immune system.
• Gut microbiome help to direct the immune system in knowing when to tolerate and when to respond to potential threats.⁶

Protection

The gut microbiome acts as a structural barrier, preventing pathogen adhesion and subsequent colonization.⁷

Individuals can have a significant impact in terms of maintaining the balance of their gut microbiome. Striving towards healthy practices, such as eating a nutritious, varied diet, or exercising frequently, individuals can thereby maximize the likelihood of achieving a healthy balance in their gut microbiome.⁸

 

Safeguarding Gut Barrier Function

The inside of the gut (the "lumen") is separated from the rest of our body by a single layer of cells called the intestinal epithelium.

This single layer of cells is so important that the body renews it entirely every 3-5 days in order to remove damaged cells.⁹ The spaces between the cells are sealed by tight junctions which regulate the permeability of the gut barrier—preventing large molecules from passing through, but allowing in ions, water, and small compounds.

However, if the efficiency of the epithelium is compromised, then gut barrier function becomes impaired—meaning that more components will be able to pass through.¹⁰

 

Mucus: Protecting the Gut Barrier

There is a mucus layer covering the intestinal epithelium, produced by "goblet cells" within the gut barrier.¹¹

This mucus layer is crucial in protecting the gut from physical damage and invasion by microorganisms—so if the thickness of the mucus layer decreases, the effectiveness of the gut barrier is compromised.¹¹

The mucus layer itself is strengthened by antimicrobial peptides (AMPs.), which help defend against microorganisms by killing or inhibiting the growth of bacteria close to the epithelium.¹¹

Cani and Jordan Nature Reviews Gastro & Hepatol 2018

 

The Threat of Leaky Gut

A balanced and diverse gut microbiome is needed for the development, maintenance, and optimal function of the gut barrier, but this composition comes under threat when there are changes in diet, stress, antibiotics, or diseases. This leads to a disruption of the gut microbiome composition and functions—a disruption referred to as dysbiosis.¹²

Dysbiosis could allow gut content such as bacterial metabolites and molecules, as well as bacteria themselves, to leak through the gut barrier and into the rest of the body. This increased epithelial permeability is also known as "leaky gut".¹²

 

The Wider Effects of "Leaky Gut"

When gut permeability is increased, pro-inflammatory toxins (for example lipopolysaccharides – LPS) can enter the bloodstream. It can lead to chronic low-grade inflammation throughout the body

"Leaky gut" is also associated with a variety of gastrointestinal disorders. They include:

1. Inflammatory Bowel Disease (IBD)
2. Irritable Bowel Syndrome (IBS)
3. Celiac Disease
4. Early Stages of Colon Cancer Development

The condition is also associated with numerous extra-intestinal disorders,^10,11 such as:

1. Obesity
2. Type-2 and Type-1 Diabetes
3. Neurological Disorders
4. Food Allergy

 

How Akkermansia muciniphila MucT Can Help Repair "Leaky Gut"

Live Akkermansia muciniphila MucT helps strengthen the gut barrier by consuming mucin, which promotes continuous mucus production to prevent pathogenic bacteria from entering the gut. However, pasteurizing Akkermansia muciniphila MucT increases the accessibility of the protein Amuc-1100, which helps replenish the mucus lining of the gut barrier and improving the epithelial tight junctions.

 

References

1. Bull MJ and Plummer NT. The human gut microbiome in health and disease. Integr Med 2014;13(6):17-22.
2. Sender R, et al. Revised estimates for the number of human and bacteria cells in the body. PLOS Biology 2016;14(8):e1002533.
3. McBurney MI, et al. Establishing what constitutes a healthy human gut microbiome: state of the science, regulatory considerations, and future directions. J Nutrition 2019;149(11):1882-1895.
4. So D, et al. Dietary fiber intervention on gut microbiota composition in healthy adults: a systematic review and meta-analysis. Am J Clin Nutrition 2018;107(6):965-983.
5. Conlon MA and Bird AR. The impact of diet and lifestyle on gut microbiota and human health. Nutrients 2015;7(1):17-44.
6. Benedict C, et al. Gut microbiota and glucometabolic alterations in response to recurrent partial sleep deprivation in normal-weight young individuals. Mol Metab 2016;5(12):1175-1186.
7. Mueller NT, et al. The infant microbiome development: mom matters. Trends Mol Med 2015;21(2):109-117.
8. Quigley E. Gut microbiome as a clinical tool in gastrointestinal disease management: are we there yet? Nat Rev Gastroenterol Hepatol 2017;14:315-320.
9. Park, J. H., et al. (2016). "Promotion of Intestinal Epithelial Cell Turnover by Commensal Bacteria: Role of Short-Chain Fatty Acids." PLoS One 11(5): e0156334.
10. Martel, J., et al. (2022). "Gut barrier disruption and chronic disease." Trends in Endocrinology & Metabolism 33(4): 247-265
11. Paone P, Cani PD (2020) Mucus barrier, mucins and gut microbiota: the expected slimy partners?Gut 69 (12):2232-2243. doi:10.1136/gutjnl-2020-322260. Download
12. Cani PD (2018) Human gut microbiome: hopes, threats and promises. Gut 67 (9):1716-1725 doi:10.1136/gutjnl-2018-316723. Download