Lauren Tessier – Research Assistant and Mold Expert
The interaction between mold and MCAS or Mast Cell Activation Syndrome is multifactorial and mimics the age-old question- “which came first—the chicken or the egg?”
Mold is everywhere- it’s ubiquitous. Some people fare well with minor exposures—such as going for a walk among the wet leaves during a fall stroll. Other people are more sensitive, and even turning a compost pile, or throwing out some moldy bread can trigger a reaction.
The reality is that mold, whether it is a mycotoxin producer or not, can impact different people in different ways and to varying severities.
Mast cells are a part of the immune system, and their activation is a well-known part of allergic reactions. However, their involvement in many normal body processes is wide reaching. They play an important role in the process of addressing infections and toxins. Plus, they help to regulate the function of different white blood cells, identify immune system threats, create inflammatory signals, and are even involved in the development of autoimmunity. They are present throughout all the tissues in the body- including the mucosa and connective tissues.
They are not activated by allergens alone. Bacteria, drugs, foods, fungi, heavy metals, organophosphates, viruses, and ‘danger signals’, neuropeptides and of course stress can also activate Mast Cells.
Once they are activated, they release many chemicals that act as a warning to the rest of the cells in the body. These products include, but are not limited to histamine, leukotrienes, heparin, tryptase, growth factors, chemokines, cytokines, serotonin and so much more. Of course, that’s not where the complexities stop—as the receptors that receive these signals reside in all tissues of the body. Therefore, activation of mast cells in one part of the body can result in symptoms in another part of the body. For instance, activation of mast cells in the gut can cause a release in histamine, which can then activate the histamine receptors in the joint space—an area worlds away when we consider the microscopic size of these cells.
As you may have guessed, molds and yeasts, members of the fungi kingdom, can trigger the activation of mast cells. This can happen not only with mold allergies, but also with fungal infections and even with exposure to mold mycotoxins.
Some studies demonstrate that people who are exposed to mold and water damaged environments become sensitized to allergens to which they may have not had previous exposure. This is impressive, as typically, someone needs to be exposed to an allergen before becoming reactive to it. Mold ultimately removes this important step in allergenic reactivity- thus speeding up the process.
Unfortunately, mold-induced increases in sensitivity do not stop with environmental allergies. Fungal exposure (from in the air, dust, soil or foods) also causes gut inflammation leading to leaky gut symptoms and mast cell mediated increases in food sensitivities.
Animal research also demonstrates that certain mycotoxins, such as Ochratoxin can exacerbate allergic reactions and even anaphylaxis. Some mycotoxins can even move the immune system toward a more allergenic state – as demonstrated by an increase in the TH2 T-helper cell subset. As if that weren’t enough, mycotoxins can also decrease the creation of the enzymes responsible for breaking down histamine, such as DAO or diamine oxidase.
While mold and mycotoxins can clearly exacerbate MCAS reactions, the connection between the two can also result in confusion in the clinical setting. Specifically speaking, things get a bit complicated when we start to try to identify which issue is the true cause of the clinical picture.
Therefore, it is incredibly important to work with a team that is well versed in not only MCAS but also mold illness.
While all of this may seem intimidating, there is hope. Knowledge is power and it can go a long way towards helping better understand and overcome health challenges, such as chronic MCAS symptoms. Thankfully, there are a handful of medical providers who understand this complex interaction and can help you find your way back to a balanced mast cell response.
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