Can Mycotoxins Cause Multiple Sclerosis?

Welcome to my blog post ‘Can Mycotoxins Cause Multiple Sclerosis?’. This blog assumes you are up to speed with what mycotoxins are, the signs and symptoms of mycotoxin illness, and how to test for them. If not, you may also be interested in the section of my blog dedicated to mycotoxins, click here, in particular:

• Mycotoxin Testing What You Need To Know
• Can Mould And Mycotoxins Cause Chronic Fatigue Syndrome?
• Can Mould And Mycotoxins Cause Gut Problems Such As IBS?

Can Mould Exposure And Mycotoxins Cause Multiple Sclerosis?

Multiple sclerosis occurs as a consequence of central nervous system neuronal demyelination. Decades of research suggest that the primary suspects (e.g., viruses, genes, immune system) are associative rather than causative agents, but a surprisingly coherent relationship can be made between multiple sclerosis and fungal toxins. Specifically, certain pathogenic fungi sequester in non-neuronal tissue and release toxins that target and destroy CNS astrocytes and oligodendrocytes. Without these glial support cells, myelin degrades triggering the onset of multiple sclerosis and its associated symptoms.

Researches have proposed that fungal toxins are the underlying cause of multiple sclerosis and thus may offer an avenue towards an effective cure (1).

How Do Mycotoxins Cause Multiple Sclerosis?

It has been proposed (1) that certain pathogenic fungi (e.g., species of Aspergillus and Candida) – masked from the immune system by their mannan coats – sequester in non-neuronal tissue, steadily releasing toxins (e.g., gliotoxin) into the bloodstream. Once across the blood–brain barrier, these toxins target CNS astrocytes, which are integral for maintaining this barrier; and oligoden- drocytes, which provide nutritive support for myelin. Without proper glial support, the blood–brain barrier weakens and myelin degrades, generating myelin debris that triggers a full scale immune response in the CNS.

Thereafter, the characteristic progression of MS ensues: further demyelination, conduction failure, redistribu- tion of sodium channels, ion imbalances, anoxia, mitochondrial depletion and axon degeneration.

Experimental evidence for this putative fungal-based etiology is limited but strongly suggestive. Fungi are recognised by the human immune system due to polymeric beta-glucan in their cell walls. Some fungal pathogens, including clinically important dimorphic fungi, are able to mask themselves with a mannoprotein coat that evades the host’s immune system, thus enabling them to colonise certain areas of the body (e.g., gastrointestinal tract) while their cytotoxic metabolites create the neurological havoc associated with MS (1).

Gliotoxin, has also been shown to impair the integrity of the blood-brain barrier contributing to ‘leaky brain’ (3).

What Mycotoxins Cause Multiple Sclerosis?

Different mycotoxins may in fact be responsible for different forms of MS

• Fumonisin B(1), isolated from species of Fusarium, which contaminates both animal feed and human food, disrupts the biosynthesis of sphingolipids, which are characteristically lost from the white matter of MS patients. Fumonisin B(1) is cytotoxic to murine microglia and primary astrocytes as well.
• Penitrem A from Penicillium crustosum causes neurological problems in laboratory animals including sustained tremors, nys- tagmus, ataxia, pseudoparalysis, mitochondrial swelling and severe neurologic dysfunction.
• Gliotoxin, a heat-stable, secondary metabolite produced by various species of Aspergillus and Candida, belongs to the immunosuppressive epipolythiodioxopiperzine class (ETP) of toxins that have been associated with various mycotoxicoses. Intracellular gliotoxin levels can reach >1000 times that of extracellular concentrations due to a unique glutathione-dependent redox mechanism, enabling gliotoxin to act in a pseudocatalytic manner. Gliotoxin destroys CNS astrocytes following intraperitoneal injections in rats, and heat-treated cerebrospinal fluid (CSF) from MS patients causes apopotic death of astrocytes and oligodendrocytes.

Geographical Correlation

The correlation between MS and pathogenic fungi extends beyond experimental investigation. Geographically, temperate areas where MS is more prevalent (i.e. above the 39th parallel in the northern hemisphere) correlate with high corn and wheat production, both of which are particularly susceptible to fungal contamination by Fusarium and Aspergillus. Based on a standard grain-based diet, daily consumption of the deadly aflatoxin from Aspergillus sp., which is found in wheat, corn and all corn-based products, can reach 0.15–0.5mg; the acute lethal dose in human is ∼10 mg (1).

Thus, continuous exposure to grain-based fungi and their airborne spores in northern regions may const tute a key environmental component of MS, and contribute to the perplexing distribution of MS cases worldwide (1).

Summary Of ‘Can Mould Exposure And Mycotoxins Cause Multiple Sclerosis?’ :

“As the scientific community struggles to understand the complex nature of this disease, and clinicians attempt to ameliorate symptoms with drugs whose side effects can be worse than the disease itself, perhaps it is time to determine the definitive role that fungal toxins play in MS etiology.” (1)

References For ‘Can Mould Exposure And Mycotoxins Cause Multiple Sclerosis?’:

1. Fungal toxins and multiple sclerosis: a compelling connection: click here.
2. Gliotoxin Aggravates Experimental Autoimmune Encephalomyelitis by Triggering Neuroinflammation: click here.
3. Gliotoxin penetrates and impairs the integrity of the human blood-brain barrier in vitro: click here.