The Joy of Mushrooms - part 1.

4 Jul

Mycotherapy, the use of mushrooms in a therapeutic context, has a long history spanning many cultures. The Greeks burnt medicinal mushrooms on ‘therapeutic points’ on the body in 455BC; in Europe there are reports of their use from 55AD, and in China they are mentioned in the herbal classic test, the Shen Nong Ben Cao, around 200 AD. There are a variety of mushrooms that are used in Chinese herbal medicine, and they are highly regarded herbs. Fu Ling (Poria), Yun Zhi (Coriolus), Ling Zhi (Reishi), Zhu Ling (Polyporus) and Bai Mu Er (Snow Fungus) are all used and all are regarded as superior herbs, defined as having excellent therapeutic action, few or no side effects that can be taken safely for long periods of time and of which it is said that prolonged use will lighten the body and confer longevity!

One of the main areas that medicinal mushrooms find use is in cancer treatment, and there have been numerous studies investigating their anti-tumour properties for a variety of cancers in humans. However, mushrooms can also be of benefit in supporting our patients - and ourselves - in a much wider range of conditions than just cancer. There are around 14000 species of mushrooms that have been identified, and of these it is estimated that 5% may be of benefit from a therapeutic perspective. My aim with this article is to give you an overview of medicinal mushrooms, which ones we might consider using and how they can be of benefit for our patients.

Although we might consider mushrooms to be more closely related to plants, genetic research suggests that fungi are more closely related to animals! Both fungi and animals derive carbon and energy from the breakdown of organic matter, unlike plants which derive carbon from carbon dioxide in the air and energy from sunlight.

Mushrooms are of benefit from a nutritional perspective, being full of vitamins, minerals, antioxidants and proteins, as well as containing a large number of pharmacologically active compounds within mushrooms that can be of benefit for various health conditions. A mushroom can contain:

Polysaccharides - these form the major class of immunologically active molecules in mushrooms, particularly the beta glucans polysaccharides, which have anti-viral, anti-bacterial and anti-tumour properties.
Essential oil - triterpenes - these have a variety of actions including being anti-inflammatory, anti-tumour, antihistamine, hypotensive and sedative.
Proteins
Phenols - sometimes considered to be antioxidants, though some research now suggests that they have more of an effect via their actions on cell signalling pathways.
Sterols -can have anti-tumour effects as well as some suggestion that they can be anti-aging.
Statins
Chitin - immunological effects, antibacterial, antioxidant activity, and has been shown to help speed wound healing.
Enzymes -these can be antibacterial.
Vitamins (vitamin B’s, vitamin C, folic acid, pro-vitamin-D) and minerals (potassium, selenium, sulphur, sodium, zinc, phosphorus).

Probably the most important of all of these groups is the polysaccharides, and these predominantly have a modulatory effect on the immune system. Immune modulation means that if an immune system is showing signs of immunodeficiency it can ‘stimulate’ or boost it, whereas if an immune system is overactive (as in immune mediated disease), mushroom polysaccharides can restore it to a more quiescent, ‘normal’ level. Extracts from 650 mushrooms have been taken that all showed the ability to modulate the immune response via compounds in the mushroom cell walls that interact with receptors on the surface of major categories of cells in the immune system. There is a lot of overlap between mushrooms and the polysaccharide compounds that they each produce; however, mushrooms all produce secondary metabolites and these can vary from mushroom species to mushroom species. So whilst all mushrooms contain immunologically active polysaccharides, each will produce different secondary metabolites that will have differing effects, conferring different effects within our bodies. Mushrooms not only support the immune response directly but can also act as a prebiotic, thus increasing the level of beneficial gut bacteria and reducing the levels of pathogens - i.e they promote a healthy gut microbiome. More and more research is demonstrating the importance of a healthy, varied gut microbiome for overall health (gut health, mental health, immune health to name but a few) both for ourselves and of our pets. There has even been some research suggesting a link between a poor microbiome and aggression in dogs.

It is worth noting that several widely used drugs are derived from mushrooms - including some antibiotics (penicillins and cephalosporins), statins, immune suppressants (Cyclosporin A) and anticancer treatments (Krestin and Lentinan).

There are various types of mushroom extracts/products, and knowing which to pick dependent on what you want to achieve is a skill. This is where utilising the knowledge of an experienced herbal vet, or vet experienced in the use of mushrooms is important, in order to pick the product that will have the best chance of benefitting the patient. Fruiting body, mycelium, mycelial biomass, aqueous (hot water) extracts, ethanolic (alcohol) extracts, spores and spore oil are all types of mushroom products, and the compounds within each can vary significantly. For example, a hot water extract contains high concentrations of polysaccharide but low levels of the more poorly water soluble triterpenes, whereas the alcohol extract contains higher levels of triterpenes but lower levels of polysaccharides. In addition, using combinations of mushrooms often gives a lovely synergy - gaining a greater therapeutic benefit than using single mushrooms alone. The challenge is picking which combination of mushrooms to use.

What can we use them for?

The short answer is a lot! They can be a lovely adjunct to conventional treatment in a variety of conditions including but not limited to:

Cancer support - probably where they are most commonly used. In Japan a polysaccharide from Coriolus (PSK - commercially known as ‘Krestin’) is a mainstream treatment for cancer in humans, used both during and after chemotherapy. Lentinan, from Shiitake mushrooms, is another extract used in the human cancer field. All medicinal mushrooms can be beneficial in cancer cases but Reishi and Coriolus seem to be used more prominently. In women, there is some research that suggests eating just 10g of whole cooked button mushrooms a day (about half a button mushroom) can reduce the incidence of breast cancer by 65%! In dogs Coriolus mushroom, the turkey tail mushroom, is used increasingly in dogs who have been diagnosed with haemangiosarcoma, a type of malignant tumour most often affecting the spleen.
Immune deficiency and immune mediated disease - the beta glucans in mushrooms can have a immune modulating role rather than an immune stimulating role, and so bring the immune system back to a ‘normal’ level.
Neurological conditions - Lions Mane Mushroom has neuro-protective and neuro-regenerative properties. It can be used for conditions such as Canine cognitive dysfunction, nerve damage, neurological disease and cancer (particularly in the brain). Reishi can also be neuroprotective and can be beneficial in epilepsy (shown in mouse models), as can the Honey fungus (Armillaria mellea).
Kidney disease - Cordyceps and Reishi can both be of benefit in patients with kidney disease.
Liver disease - Reishi, Cordyceps and Shiitake can all be useful in these patients.
Heart disease -Reishi, Cordyceps and Snow fungus can all support cardiovascular health
Diabetes/pancreatitis - The button mushroom seems to have a pancreas protective role, as well as potentially benefiting diabetic patients. In one study was shown to be of benefit to mice with diabetes. A hot water extract from the common button mushroom given to induced diabetic mice increased blood insulin by 78.5%.
IBD - by improving the microbiome with the use of mushrooms as a prebiotic, it is possible that an improvement in gut heath could be seen. IBD also has an immune dysfunction component, and by their effect on modulating the immune response it is possible that mushroom use may be of benefit in these cases. Traditionally Lions Mane was used for stomach pathology and is considered gastroprotective.
Support for geriatric patients - it is worth remembering that these mushrooms contain many vitamins and minerals as well as proteins, sugars, lipids and enzymes. They are a good micronutrient and macronutrient food source quite apart from the compounds within them that can benefit our golden oldies from an immunological, mental and physical perspective. They can improve stamina, improve digestive functions, improve adaptation to stress. Many of our older pets may also have concurrent disease processes already listed above, and these can be supported with the use of medicinal mushrooms.

Part two of this two part blog series will look at these mushrooms in more detail.