L-Ergothioneine (EGT): A Diet‐Derived Antioxidant with Therapeutic Potential
1. Longevity Vitamins L-Ergothioneine (EGT)
L-Ergothioneine (EGT) also known as a “Longevity vitamins”. Longevity vitamins refer to nutrients including vitamins, minerals and other elements that are key to healthy aging. The list of longevity vitamins by Bruce Ames includes vitamin A, vitamin B1, vitamin B2, vitamin B6, vitamin B12, biotin, vitamin C, choline, vitamin D, vitamin E, folic acid, vitamin K, ergothioneine, niacin, pantothenate, calcium, chloride, chromium, cobalt, copper, iodine and iron among others.
L-Ergothioneine is a powerful amino acid antioxidant that has been considered the “longevity vitamin.”
Humans cannot synthesize L-Ergothioneine, so it must be obtained through the diet. L-ergothioneine powder is readily available supplement sold as a vitamin.
Humans produce a highly specific transport protein for L-(+)-Ergothioneine (EGT) powder (497-30-3), which highlights its importance and makes it highly bio available and avidly retained, particularly in tissue where it plays a powerful and protective role.
2. What Is L-Ergothioneine (EGT)?
L-ergothioneine (EGT) is a naturally occurring sulfur-containing amino acid only biosynthesized by fungi and mycobacteria in the soil. It is avidly taken up from the diet by humans and other animals through a transporter, OCTN1. Ergothioneine then accumulates to high levels in certain tissues undergoing relatively high levels of oxidative stress, such as erythrocytes, airway epithelium, liver, and kidneys.
Ergothioneine is not rapidly metabolised, or excreted in urine and is present in many, if not all, human tissues and body fluids. It is a stable antioxidant molecule and does not degrade at high temperature and high pH.
While mushrooms are the richest dietary source of ergothioneine, other ergothioneine rich foods include black beans, red meat and oats. Mushrooms are also a good dietary source of glutathione which together with ergothioneine are excellent dietary antioxidants. However, ergothioneine mushroom species show variations in the levels of these antioxidants.
3. L-Ergothioneine (EGT) Benefits
L-ergothioneine (EGT) acts as a cation chelator, bioenergetics factor, immune regulator and antioxidant.
L-ergothioneine benefits include:
i. Acts as an antidepressant
Depression is a neural disorder and is reported to affect 20% of the world’s population. It was found that in the depressed individuals, oxidative stress increases and level of antioxidants decreases, hence the need for antioxidant compounds.
Interestingly, l-ergothioneine exerted neuronal differentiation in addition to antioxidant activity in a study with mice
ii. Treatment of preeclampsia
This is a late pregnancy-associated disorder due to the formation of defective placentation. Endothelial dysfunction occurs due to lysis of red blood cells hence iron concentration increases and leads in the production of reactive oxygen species (ROS) in the placenta.
L-ergothioneine is shown to chelate iron and reduces the injury due to ROS.
iii. Application in cosmetic products
Cosmetic industry is growing rapidly over the recent past, and today ingredients from natural sources are preferred due to adverse side effects by chemicals. Exposure to intense sunlight for long duration results in ultraviolet ray-induced oxidative damage of biomolecules in the skin cells which causes sunburn, photoaging, and skin cancer.
L-ergothioneine is used as an important ingredient in cosmetic products, especially in sun-screen lotions as it has UVA protection property. It is readily absorbed when applied on the skin.
L-ergothioneine skin protectant against ultraviolet (UV)-induced ROS generation and damage mechanism is known. EGT absorbs light in the UV range and hence this physical property accounts for some of its ability to block UV damage.
Photoaging is the cleavage of collagen and destruction of vital molecules. L-ergothioneine has shown effective inhibition of the collagen cleavage and inflammation.
iv. Treatment of Neurodegenerative Diseases
The neurodegenerative diseases (ND) like Alzheimer, Parkinson, and Huntington’s are attributed to increased production of free radicals. It is understood that the free radical scavenging is the mechanism of clearing the stress in the neural cells.
Selective damage to mitochondrial DNA by oxidative stress has been implicated in neurodegenerative diseases, especially Parkinson’s disease. Thus, l-ergothioneine mitochondria DNA protection from the superoxide generated in the course of the electron transport cycle is suggested.
Anti-neurogenetic action of edible mushroom extracts in vitro cell line studies demonstrated that the bioactive compounds are responsible for neuroprotective activity. Nature-based nutraceuticals like L-ergothioneine from medicinal mushrooms are suggested as better therapeutic agent for neurodegenerative diseases.
v. Role in cardiovascular diseases
Through studies of ischemia/reperfusion (IR), a process involving oxidative stress, EGT has been shown to have a protective role in cardiovascular disease. EGT is reported to protect cardiac and liver tissue from damage in vivo during IR.
The mechanisms by which this protective action is achieved may be through the reduction of ferrylmyoglobin protecting tissue from oxidative injury and also through modulation of heat shock protein 70 and pro-inflammatory cytokines.
In addition, EGT may protect through chelators of iron and copper which have been shown to be protective by decreasing free radical production during IR.
vi. Treatment of kidney disease and cancer
It has been shown that patients with chronic kidney disease (CKD) have lower blood ergothioneine levels. Indeed, CKD is well known to be involved in increased oxidative damage and ergothioneine hence, might be helpful in decreasing this by accumulating in the kidney.
Ergothioneine cancer treatment is speculated since differential mRNA expression of OCTN1 uncovered significant differences in certain cancers. If indeed, certain cancers do accumulate EGT to help protect them, perhaps against chemotherapy (whose effects are known to involve oxidative stress. It therefore means therapeutic possibilities such as depleting EGT and/or blocking the transporter.
Some other l-ergothioneine benefits include:
- Ergothioneine hair and nail health.
- Treatment of diabetes
- Chronic inflammatory diseases treatment.
4. L-Ergothioneine (EGT) Dosage
It has been reported that EGT dosage of up to 30 mg/day for adults and 20 mg per day for children has no genotoxicity by EFSA panel report.
In a human study, l-ergothioneine 5 mg and 25 mg/day dosage for 7 days were found to have no adverse effects.
5. L-Ergothioneine (EGT) Research
L-Ergothioneine (EGT) became a popular focus of study when it was discovered in red blood cells of animals in 1928. Due to its accumulation in the erythrocytes and its natural antioxidant properties, ERGO was proposed as a possible therapeutic treatment for red blood cell disorders which were predisposed to oxidative damage.
Many advances in research of EGT have been achieved in recent years including the identification of a highly specific transporter in higher organisms and humans and also better understanding of its distribution. Although, the true physiological role of EGT is yet to be fully determined, EGT has been shown to possess numerous antioxidant and cytoprotective effects in vitro and a few in vivo, including free radical scavenger activity, radio protective properties, anti-inflammatory actions and protection against UV radiation or neuronal injuries.
The current research focuses on the in vivo effects to evaluate the molecular mechanisms of EGT these cytoprotective in humans’ physiology.
6. L-Ergothioneine (EGT) Safety
L-ergothioneine supplements are widely accepted as important food supplements due to its health benefits. LE has been given a “generally recognized as safe (GRAS)” status by FDA, USA.
The pharmacology studies of l-ergothioneine in human beings showed no known adverse effect up to 25 mg/day for 1 week.
In animal models, l-ergothioneine administration up to 1600 mg per kg of body weight did not show any adverse effects.
Also, no mutation activity was observed in a bacterial reverse mutagenesis assay of the l-ergothioneine with a concentration of 5000 μg ml−1. A clear scientific evidence of ergothioneine uptake in human being through regulated trans-porter by kidney is available.
In human tests of liver function and lipid profile, no adverse effects were reported by administration of pure l-ergothioneine.
7. What Foods Are Rich in L-Ergothioneine (EGT)?
Since EGT cannot be synthesized by humans, it is only available from dietary sources. Plants and animals also accumulate it to some degree; however, the main natural dietary source of EGT is basidiomycete mushrooms, where some species contain up to 7 mg of ERG per gram dry weight.
The L-ergothioneine foods are:
- Edible ergothioneine mushroom species such as Sparassis crispa,Tremella foliacea, Lepista , Suillus luteus and Ramaria botrytis.
- Black beans,
- Oat bran, and
- Kidney beans.
8. L-Ergothioneine (EGT) Supplement
L-ergothioneine supplements are extracted from mushrooms or synthesized chemically and can be used as food, beverages, and powder or capsules forms. Chemically, L-Ergothioneine (EGT) Supplement is a derivative of thiol histidine, i.e. 2‐thio‐l‐histidine‐betaine.
Ergothioneine and glutathione supplement are available online. Customers of ergothioneine buy it from most trusted suppliers online and stores.
Ergoneine developed and patented by Tetrahedron is a source of synthetic L-ergothioneine authorized by the European Commission. L-ergothioneine powder is readily available while l-ergothioneine water solution may be availed on request.
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