Gastrointestinal Health: The mucosal barrier Flashcards
Q: What is the mucosal barrier and its role in the GIT?
A: The mucosal barrier is a layer of mucus covering the entire GIT, acting as a thick barrier between immune-stimulating contents and immune cells in the gut wall, serving as the first line of defense.
Q: What are the key components of mucus in the mucosal barrier?
A: Mucus contains 96–98% water, glycoproteins called mucins, IgA, and antimicrobial peptides such as α and β defensins.
Q: What happens to the mucosal barrier in ulcerative colitis?
A: In ulcerative colitis, the inner mucosal lining becomes permeable, allowing bacteria to come into close contact with host tissues, resulting in inflammation.
Q: What are some consequences of a disturbed mucosal barrier?
A: A disturbed mucosal barrier can lead to bacterial translocation and leakage of lipopolysaccharides (LPS), causing metabolic endotoxaemia.
Q: How can you support the mucosal barrier through diet?
A: Support the mucosal barrier by optimizing dietary fiber, consuming polyphenol-rich foods (e.g., green tea, blueberries, pomegranates), and including mucopolysaccharides like slippery elm, marshmallow root, and seaweeds.
Q: What foods contain polyphenols that benefit the mucosal barrier?
A: Foods rich in polyphenols that support the mucosal barrier include green tea, blueberries, cranberries, blackcurrants, and pomegranates.
Q: What are mucopolysaccharides, and how do they support the mucosal barrier?
A: Mucopolysaccharides, found in plants like slippery elm, marshmallow root, and flaxseeds, help support the mucin lining of the mucosal barrier.
Q: What does increased intestinal tight junction permeability lead to?
A: Intestinal tight junction disassembly leads to increased LPS load and excessive immune reactions.
Q: What supplements and nutrients support the intestinal epithelial barrier?
A: Supplements and foods that support the intestinal barrier include glutamine, zinc carnosine, vitamin A, N-acetyl glucosamine, and bone broth.
Q: What are two common tests for assessing intestinal tight junction permeability?
A: Testing for permeability can be done using Zonulin (stool test) or Cyrex Labs Array 2 (serum antibodies).
Q: What is secretory IgA (SIgA), and what is its function in the gut?
A: Secretory IgA resides in the mucosal lining, protecting the intestinal epithelium from toxins and pathogenic microbes by promoting immune exclusion, which blocks antigens from accessing epithelial receptors.
Q: What role does SIgA play in immune tolerance?
A: SIgA helps in immune tolerance by tagging microbes, which helps the immune system identify and clear antigens.
Q: What are the common causes of low SIgA?
A: Low SIgA can be caused by ongoing emotional or physical stress, NSAID use, and antibiotics.
Q: How does low SIgA affect the risk of gastrointestinal infections?
A: Low SIgA increases the risk of gastrointestinal infections, including SIBO.
Q: What are some ways to increase SIgA levels?
A: Increase SIgA by addressing stress, using Saccharomyces boulardii, consuming medicinal mushrooms, and ensuring adequate intake of vitamin A, vitamin D3, polyphenols, chlorella, probiotics, prebiotics, and Echinacea.
