Immune Support with Mushrooms
The use of mushrooms, mushroom extracts and mushroom combinations in the care of human health is thousands of years old. There are few agents in the record of human history that can rival the duration, impact, or reputation of mushrooms in traditional medicine practices. When it comes to immune support, mushrooms are an essential component.
The immunomodulatory effects of mushrooms are due, in part, to the beta glucans and other potent polysaccharides they contain, but supported as well by antioxidant, phenolic and indolic compounds.
Many of the studies involving mushrooms demonstrate that they positively support immunity, as well as healthy inflammatory balance. The research demonstrates that medicinal mushrooms may stimulate T-cell and natural killer cell function, support the development and activity of lymphocytes and macrophages, and modulate cytokine production.
According to a 2017 review published in the International Journal of Medicinal Mushrooms, mushrooms contain numerous bioactive polysaccharides or polysaccharide-protein complexes that have been shown to influence innate and cell-mediated immune responses. The author reports that “More than 600 studies have been conducted worldwide, and numerous human clinical trials on MMs [medicinal mushrooms] have been published.”
Mechanisms of Immunological Benefit
Chang et al. in 2014 looked at reishi mushroom (Ganoderma lucidum) stimulating NK cell cytotoxicity by inducing NKG2D/NCR activation and secretion of perforin and granulysin. Their conclusion was that Ganoderma, in their research, showed a cellular and molecular mechanism to account for the reported effects of G. lucidum extracts in humans. Of note, this was also an aqueous extract.
This mechanism actually has other crossover effects as well. Perforin and granulysin are two cytolytic molecules that natural killer cells use to help kill cells without “self” surface receptors. Enhancement of natural killer cell function is well established in the basic immunology sciences as supporting “surveillance” immunity.
The Form of an Extract Does Matter
Lu et al. in their paper, “Immunomodulatory properties of medicinal mushrooms: differential effects of water and ethanol extracts on NK cell-mediated cytotoxicity,” make an excellent point regarding the form of a mushroom extract and its effect on the mechanism and actual immunologic effect of the agent.
Through the same mechanisms mentioned above, these researchers showed that aqueous extracts (note: most papers reviewed above used this form) allow these natural killer cell benefits and alcohol extracts block it. From the conclusions: water extracts enhance NK cell cytotoxic activity, whereas ethanol extracts inhibit cytotoxicity. This difference in extraction processes has been well known in traditional herbal medicine and generally in botanical medicines and herbalism, the “method” of extraction is important to clinical outcome. This paper, and the fact that the majority of the studies presented today used aqueous extracts, enhances the notion that such extracts are likely superior to alcohol extracts in the case of immune responses of mushroom-based agents.
Immunomodulation and Balance
When working effectively, the human immune system is amazing. But when the immune system is hyper-responsive it inappropriately reacts to harmless substances such as pollen, pet dander, or foods. This overactivation is a troublesome issue for many patients, so balancing the immune response becomes a key clinical goal.
Mushroom extracts have been shown to help modulate and balance an overactive immune response. Authors of a 2016 review published in the journal Molecules stated, “The ability of mushrooms to modulate immune function is mostly attributable to their bioactive compounds, including polysaccharides, proteins, proteoglycans and triterpenoids.”A 2009 study evaluated the immune-modulating effects of maitake extract in particular and found that there was a balancing effect. A 2012 study on Agaricus blazei published in Advances in Pharmacological Sciences found that this mushroom specifically supports immune function through “amelioration of a skewed Th1/Th2 balance”. A balanced immune response is important for all patients and especially those who experience immune challenges caused by Th1/Th2 imbalance.
Effects on Inflammatory Balance
Therkelsen et al. discussed the effect of Agaricus blazei Murill-based mushroom extract on the symptoms, fatigue and quality of life in patients with Crohn’s disease. The results showed significant improvement on symptoms, for both genders, in the mushroom treated group. The patients did not report any adverse effects of the mushrooms. The authors concluded that “Crohn’s patients with mild to moderate symptoms may have beneficiary effects of [the mushroom therapy] as a safe supplement in addition to conventional medication.”
In 2015, Changda Liu et al. reported on the anti-inflammatory effects of Ganoderma lucidum (reishi) triterpenoid in Crohn’s disease associated with down-regulation of NF-κB signaling. In 2014, Bhardwaj et al. reported on the suppression of inflammatory and allergic responses by Ganoderma (reishi).
The effects of the mushroom in the GI tract, as well as systemically, are likely behind the benefits noted. These mushrooms (as many do) exhibit immunomodulatory effects which are so crucial to the care of people with autoimmunity and allergies.
Malnutrition and Muscle Wasting
Llauradó et al. studied oral administration of an aqueous extract from the oyster mushroom, Pleurotus ostreatus, that enhances the immunonutritional recovery of malnourished mice. Though mouse studies are not preferred over human studies, gaining the mechanistic information one can from an animal study in a condition such as malnourishment can “fast track” the trial of a natural agent in humans with the same or similar condition.
In wasting syndromes we know that a multi-agent approach is always required and that the more “at the core” of the cachexia biology the agent works, the more beneficial an addition to the therapy plan it is. The authors make some very promising discoveries in this respect which—when compared to the biological “faults” created by cachexia—make this agent worth a trial in cachexic and underweight patients:
“Oral treatment with CW-P normalized haemoglobin levels, liver arginase and gut mucosal weight. CW-P increased total liver proteins and DNA and protein contents in gut mucosa. Pleurotus extract provided benefits in terms of macrophages activation as well as in haemopoiesis, as judged by the recovery of bone marrow cells and leukocyte counts. Moreover, CW-P stimulated humoral immunity (T-dependent and T non-dependent antibodies responses) compared to non-supplemented mice. CW-P extract from the oyster mushroom can be used to develop specific food or nutritional supplement formulations with potential clinical applications in the immunotherapy.”
With the caveat that malnutrition and wasting must be treated in a well-rounded manner, the availability of a potentially strong synergist to nutritional therapies in an aqueous form may be potentially lifesaving to these patients.
Implications for Practice
Medicinal mushrooms have a great pool of data supporting their use in modern times. They are also some of the most treasured agents in traditional practices in the thousands of years of recorded history we have. If an agent has “stood the test of time” (and we know it to be effective), the science will not only prove that out, but also repeatedly support and elucidate more and more mechanisms explaining the clinically noted outcomes. Decades of research have shown that mushrooms as agents for immune support and modulation are both safe and effective.