The intestinal permeability is a condition which characterizes many diseases, such as IBC, IBD, celiac disease. The enterocytes composing the intestinal mucus layer, in a healthy condition, the strongly joint by the so called tight junctions, which allows the building of a physical barrier, effective in nutrients absorption but it prevents the passage of macromolecules, pathogens and toxins in the intestinal lumen. Various factors related to life style and nutrition let the intestinal barrier losing its integrity, with the tight junctions that allow the passage of macromolecules, pathogens and toxins, activating inflammation and other symptoms consequently.
Hericium erinaceus is an edible and medicinal mushroom, exploited in traditional Chinese medicine to treat gastrointestinal diseases. Hericium has many beneficial properties: immune stimulants, antimicrobial, antioxidant, thanks to many bioactive compounds isolated both from fruiting bodies and mycelium. Hericium effects on gastrointestinal health are related to its immunomodulation, the interaction with gut microbiota and the contribution to intestinal integrity.
Immunomodulation
The immune modulating properties of Hericium are related to its polysaccharide content, especially the β-glucans, and Hep3 protein. They are able to interact with the elements of the immune system, as macrophages, with the consequent involvement of the adaptive and innate immune response and the activation of the anti-inflammatory cascade.
The anti-inflammatory effect of Hep3 protein was evaluated by Diling and colleagues (2017): the intestinal mucosa of mice with induced colitis treated with Hep3 has a lower degree of inflammation, similarly to the healthy control, as shown in the figure.
Prebiotic and reparative effect
Insoluble β-glucans of Hericium are prebiotics: they cannot be digested and adsorbed at intestinal level, so they are metabolized by the bifidobacteria of the gut microbiota, contributing to their growth and proliferation. Moreover, the β-glucans mentalism produces short chain fatty acids which contributes to the expression of the intestinal tight junction. These acids are also important for the metabolism and homeostasis of intestinal epithelial cells and represents a source for the connective fibroblasts for tissue repairing and regeneration.
In conclusion, Hericium administration via dietary supplements represents a strategy to improve the diseases characterized by increased intestinal permeability, thanks to the multi-factorial approach: the effect on the intestinal tight junction through the release of short chain fatty acids from the insoluble β-glucans and the repairing and regenerative effect. Indirectly, it regulates the microbiota composition through the prebiotic action and regulates inflammation, which is very common in case of increased intestinal permeability.
References
Diling, C., Xin, Y., Chaoqun, Z., Jian, Y., Xiaocui, T., Jun, C., … & Yizhen, X. (2017). Extracts from Hericium erinaceus relieve inflammatory bowel disease by regulating immunity and gut microbiota. Oncotarget, 8(49), 85838.
