Methylation is more than just a buzzword. Methylation reactions are critical to our bodies’ proper function, as they impact such crucial components of health as the citric acid cycle, protein synthesis, DNA replication, gene expression and much more. Understanding the chemistry behind these reactions can illuminate helpful possibilities for your patients who need added support for methylation. There are likely many – both patients and possibilities.
In fact, it has been estimated that 40 percent of the population may have some sort of variation in the MTHFR gene, which regulates the methylenetetrahydrofolate reductase (MTHFR) enzyme and its activity.1 Because these variations can directly affect methylation processes through their impact on the folate cycle, they are a necessary component of any conversation about healthy methylation reactions.
But let’s dive into the basics of methylation first.
Methylation is the addition or removal of a methyl group to a compound. A methyl group is simply one carbon atom connected to three hydrogen atoms, or a CH3 molecule. Hundreds of our bodies’ reactions can be called “methylation reactions” – methylation does not refer to a specified reaction that bears this title. We can think of the addition and subtraction of methyl groups as a switch. When a methyl group is added to a compound, a reaction begins. Perhaps it is the turning “on” of a gene or the activation of one enzyme. When a methyl group is taken away from a compound, a reaction such as this is being turned “off.”
Because methyl groups serve such an important function, we can easily surmise that methylation plays a central role in biochemical processes at the cellular level.
This paper will cover factors that may lead to impaired methylation, with a focus on the common single nucleotide polymorphisms for which you can test. It will also cover various bodily functions that may be affected by impaired methylation, and finally, address the nutritional support necessary for a healthy methylation regimen.
Fill out a downloadable PDF version of the guide you can reference later.
Methylation can be impaired by decreased MTHFR enzyme activity, which can lead to impaired folate metabolism and therefore, a negatively impacted folate cycle. Impaired enzymatic activity itself has several potential causes. Lifestyle choices (alcohol, diet, etc.) can all interfere with folate metabolism and the methylation cycle. Another cause: Single nucleotide polymorphisms, or SNPs, that may occur in the MTHFR gene.
Many genes, like MTHFR, are instructions for enzyme building. For many enzymes, the encoding gene has two or more versions of alleles that differ by just one nucleotide. These polymorphisms are inherited. Many SNPs have been identified in the MTHFR gene, but mutations in two alleles in particular are better-studied and well known. These alleles are known as C677T and A1298C.2 Loosely, the first causes concerns with conversion to active folate and the second causes concerns with the body’s ability to use the active folate. We will cover the process of testing for SNPs in these particular alleles, and what the results may mean for your patients, later in this paper. For now, let’s discuss the ways in which SNPs in the MTHFR gene may impair methylation.
Reduced activity of the MTHFR enzyme may result in decreased concentrations of folate, specifically in the active form in RBCs and in serum plasma. These decreased concentrations may occur because we bring folate into our bodies through naturally occurring amounts in food, which is in the DHF form, and through the folic acid added to foods. (It is important to note that an extra enzymatic reaction is required to convert folic acid to DHF, and this can of course be affected by certain SNPs.) The body converts DHF to THF, then to 5,10-methylenetetrahydrofolate, then, finally and irreversibly, to the active form of folate, 5-MTHF, an important methyl donor. It is evident that the healthy activity of the MTHFR enzyme is crucial to proper conversion.
Reduced MTHFR activity may also result in increased plasma homocysteine levels. Further, SNPs in this enzyme may reduce a cell’s ability to transfer methyl groups to another cell.
5-MTHF is the active form of folate that the body uses to help remethylate homocysteine into methionine.* The methionine cycle is closely related to the folate cycle through these means. 5-MTHF donates the one carbon methyl group that allows the homocysteine-to-methionine conversion to occur. As we know, elevated homocysteine levels can be biomarkers for a variety of health concerns, including and most commonly for cardiovascular health issues. Further, folate metabolism is linked to BH4, a cofactor essential to the formation of certain neurotransmitters.
Here, we’ll explore multiple areas of health affected by methylation reactions.
Methylation has a primary role in phase 2 of the body’s detoxification process, as it converts toxins from their less soluble, insoluble and fat-soluble forms into water-soluble compounds, allowing for excretion. We can think of methylation as a tagging and execution system in this function, as it first identifies the substances, then alters the substances, and then helps the body eliminate the substances. Without sufficient methyl groups, that flagging may fall behind, allowing for an accumulation of toxins and/or heavy metals.
While it is only one of several processes that may occur as phase 2 conjugation, methylation’s importance to the detoxification process cannot be overstated. Methylation attaches the flagged toxins to methionine. It helps to remove excess hormones, neurotransmitters, and of course, homocysteine.3
Acting as an indirect methyl donor, DMG plays a role in liver health through supporting detoxification functions. * Betaine, or TMG, also offers support for a healthy liver and its healthy function.* In the liver, TMG transfers one of its three methyls to homocysteine for its conversion to methionine, thus becoming DMG in the process. We can see that TMG’s donation both produces the useful methionine from the harmful homocysteine and leaves an indirect methyl donor, DMG, behind in the process. *
Folate is necessary for the body to properly synthesize serotonin, epinephrine and dopamine.* As mentioned, active folate, 5-MTHF, is involved in homocysteine remethylation and the creation of methionine. SAM-e, a methyl donor itself, is a metabolite of methionine. When 5-MTHF is not present, low mood may result, due to a decrease in both SAMe and neurotransmitter levels in cerebrospinal
fluid.4
Remember BH4? It is an essential cofactor to the important hydroxylase enzymes, which participate in the metabolism of certain amino enzymes (tryptophan to 5-hydroxy-tryptophan, phenylalanine to tyrosine and tyrosine to dopamine), producing neurotransmitters. BH4 is dependent on folate metabolism, as 5-MTHF is a primary methyl donor for the BH4 cycle, known as the tetrahydrobiopterin cycle.5 That means we know of at least two ways that lack of sufficient folate and methylation may impact mood.
Further, related to homocysteine, those with the C677T SNP and elevated serum homocysteine are at increased risk for mental health challenges.6 Managing homocysteine levels is also a way to support healthy brain function as we age.7 We also know that low blood levels of folate and B12 and high levels of homocysteine correlate with low mood, especially in the elderly.8
COENZYME Q10 SYNTHESIS
As we know, coenzyme Q10 is critical to our body’s energy production process, through its role in the mitochondrial respiratory chain.* The synthesis of CoQ10 requires adequate levels of some substances in the methylation pathway - specifically, SAMe, which is generated within the methylation cycle. (Note that TMG donates a methyl group to become DMG, which donates a methyl group to become SAMe.) Importantly, statins can assist in the decline of CoQ10 levels in the body, meaning patients taking statins should place particular value on their ability to effectively methylate, ensuring that their ability to synthesize the CoQ10 they have available remains intact. At least seven enzymes encoded by COQ2-
8 catalyze several reactions in order to synthesize CoQ10, including hydroxylation and methylation.9
HOMOCYSTEINE
When folate conversion and methylation are impaired, the resulting impaired ability to recycle homocysteine can give rise to a multitude of health concerns, one of the most well known of which is cardiovascular challenges. The connection between cardiovascular health and homocysteine levels is an oft-debated one. Recent meta-analyses have revealed that the relationship between elevated homocysteine levels and certain cardiovascular challenges may be causal.10,11 In any case, elevated homocysteine has been associated with such influential health factors as lipid peroxidation, perforation of vascular smooth muscle and endothelial dysfunction.
So we know that elevated homocysteine levels are associated with a variety of health concerns. But what factors cause elevated homocysteine? As discussed, MTHFR SNPs, as well as SNPs in other genes, can be contributing factors, through one of many different mechanisms. Another possible
contributor? Nutrition.
Lack of B12, for example, even with sufficient 5-MTHF, can create an intracellular deficiency of THF called the “folate trap” because deficiency of B12 precludes methionine synthase. The methylcobalamin form of the vitamin is a required cofactor in remethylation via this enzyme. A decline in methionine synthase means a possible buildup of MTHF that cannot donate its methyl groups to remethylation, which may mean an increase in homocysteine. Vitamin B-12 and folic acid are the only two vitamins known to share a direct metabolic link in this fashion: each demands the other.
Low folate levels alone can also be a factor in elevated homocysteine levels, because of the requirement of 5-MTHF in the homocysteine to methionine conversion. The rate of that reaction, too, is slower when folate is low.
Another nutrient, betaine, is also a methyl donor, and is required for the liver and kidney route for remethylation. The transfer of trimethylglycine to homocysteine, which results in methionine, can be catalyzed by the enzyme betaine homocysteine s methyl transferase. It is clear, then, that low levels of betaine must influence homocysteine; and in fact, there is evidence that both lowered levels of betaine and of its precursor choline are associated with high levels of that harmful amino acid, and that low-dose betaine supplementation can lower plasma levels of homocysteine.
Finally, B6 may play a role in homocysteine level management, as it is a cofactor at two different points in the transsulfuration pathway that converts homocysteine to cystothionine, then to cysteine.* If B6 is not present, the conversion to cystothionine won’t occur, leaving homocysteine trapped in the methionine cycle, which can cause homocysteine levels to become too high.12,13
Each of the above factors can contribute to elevated homocysteine levels, which, as mentioned, can contribute to a variety of health concerns. We covered cardiovascular involvement , lipid peroxidation and endothelial dysfunction – but elevated homocysteine levels have also been linked to neurological health and bone health in the elderly.14,15,16
Consider genetic testing to confirm impaired methylation capabilities. To focus your testing, concentrate on the two alleles C677T and A1298C. You may find one of various results. If you find that either of these genes are not wild type, you will know your patient’s MTHFR function is compromised. Remember that an absence of a mutation in these two sites does not necessarily mean your patient does not experience impaired MTHFR activity due to one of the many other (over 40 known) SNPs in this gene, as well as to the other possible causes of impaired activity.17
You may discover any one of the following outcomes:
C677T - / - A1298C - / - = No mutations AKA Wild Type
C677T + / + A1298C - / - = Homozygous C677T
C677T + / - A1298C - / - = Heterozygous C677T
C677T + / - A1298C + / - = Compound Heterozygous C677T/A1298C
C677T - / - A1298C + / - = Heterozygous A1298C
C677T - / - A1298C + / + = Homozygous A1298C
C677T - / - A1298C - /- = No mutations AKA Wild Type
If you identify no mutation in either allele, you can rule out the most common issues with 5,10 MTHF’s conversion to 5-MTHF. A wild type result for both alleles tells us that a genetic abnormality is unlikely, but bear in mind that there are over 40 known SNPs in the MTHFR gene.
C677T + / - A1298C - / - = Heterozygous C677T
C677T - / - A1298C + / - = Heterozygous A1298C
If the mutation is heterozygous, or present in just one of the SNP sites in one of the two MTHFR gene copies, 5-MTHF production will be slower. In particular, the C677T mutation may have a greater impact on 5-MTHF, while an A1298C mutation may have a greater impact on BH4 recycling, making it especially relevant to neurological health. In the heterozygous C677T mutation, enzyme activity is
reduced by about 40%.18
C677T + / - A1298C + / - = Compound Heterozygous C677T/A1298C
A compound heterozygous type, wherein one copy of the gene has a C677T mutation and the other copy the A1298C mutation, can also cause reduced enzyme activity in MTHFR.
In one article concerning the spectrum of mutations, authors note that previous studies have found the C677T allele (especially the homozygous genotype or a combination of the allele with other MTHFR variants) could contribute to various health concerns including hyperhomocysteinemia, increased risk of cardiovascular disease, depression, bipolar disorder, fetal neural tube defects, Alzheimer’s disease and more. Despite a less profound effect on homocysteine levels, the A1298C could contribute if present with C677T and low folate levels.19
C677T + / + A1298C - / - = Homozygous C677T
The homozygous mutation means either the C677T or the A1298C mutation is found in both copies of the gene. When both copies of the gene show the C677T mutation, enzyme activity is reduced by about 70%, but at least by 50-60% at body temperature. That is the highest reduction of any of the likely scenarios.20,21
C677T - / - A1298C + / + = Homozygous A1298C
When the A1298C site shows homozygosity, enzyme activity may be reduced by up to 40%, but because this polymorphism may contribute more to the BH4 recycling process, it seems that people displaying this homozygosity do not also show elevated homocysteine levels.
Rarely do we see one copy of the gene with mutations in both alleles, or both copies with mutations in both alleles. These results would likely indicate the slowest folate metabolism of any of the results described above, and it is presumed we don’t see a compound homozygous type often because it may compromise fetal viability.22
We may want to find a purported “fix” for each of the concerns herein described, but the truth is, many drugs that surround the processes affected by methylation are known to be less effective than we’d desire. For example, the largest trial of patients with low mood found that 70 percent of patients did not achieve remission using one strategy alone.23,24 As we know, mental health is affected by a multitude of factors. We also know that methylation impairment may affect the levels of neurotransmitters we produce, indicating that supplementation with nutritional cofactors that help our bodies move around their own methylation roadblocks may be a helpful addition to a health regimen.*
With emerging knowledge that individual genetics and lifestyle choices can greatly affect our ability to sufficiently methylate comes the need for support. That’s why supporting healthy methylation is becoming one of the most recognized, foremost approaches to supporting overall health. From the brain to the cardiovascular system, from energy production to detoxification capabilities, the accessibility of methyl groups is essential. Methyl Benefits™ goes beyond conventional mg levels and provides unparalleled methylation support.*
VITAMIN B2
This vitamin helps the body convert other B vitamins for use, and is critical for the utilization of B6 and folate. It supports methylation through supporting those conversions, and also supports growth, red blood cell formation and normal levels of homocysteine.*
VITAMIN B6
B6 is a required element of the folate cycle. The transsulfuration pathway, where cystathionine breaks down to cysteine and homoserine, is B6 dependent. This reaction results in cysteine, a precursor of glutathione, and supporting its health is another way (aside from supporting methylation) to support normal homocysteine levels.* Vitamin B6 is needed for more than 100 enzymatic reactions in the body, and required for normal brain function, nerve function, and the synthesis of certain neurotransmitters and lipids that are part of the myelin sheath.*
Methyl Benefits™ provides vitamin B6 in the pyridoxal-5-phosphate form. Many supplement formulas include the form of B6 known as PNHCl, which requires an additional enzymatic conversion step in the liver (compared to P-5-P). In order to optimize the body’s utilization of B6 for clinical outcomes, P-5-P may be a more advantageous choice.25
FOLATE
Provided in this formula as [6S]-5-methyltetrahydrofolic acid from 5,000 mcg DFE of Quatrefolic® [6S]- 5-methyltetrahydrofolic acid, glucosamine salt, folate is, as evidenced by the importance of proper MTHFR function, a critical component of healthy methylation. It is required for the donation of methyl groups to homocysteine in order to produce methionine.
Quatrefolic® from Gnosis is a new generation of folic acid. It represents a breakthrough in folate supplementation with regard to an active, stable, and highly bioavailable form when compared to folic acid and the methyl derivative folate. This form is easily utilized and stored in the body. Quatrefolic® uses a glucosamine salt which has been proven in both human animal studies to have greater bioavailability over calcium salt versions.
VITAMIN B12 (AS METHYLCOBALAMIN)
Methylcobalamin is the active form of B12. It does not have to be converted for use, which means it starts working right away.* It’s also the form used to make the aforementioned methionine synthase enzyme, which converts homocysteine to methionine. Remember also that low B12 can lead to low THF, which is known as the folate trap.
TRIMETHYLGLYCINE (TMG) AND DIMETHYLGLYCINE (DMG)
Both TMG and DMG impact the homocysteine and folate pathways to provide the opportunity for SAMe to function properly.* TMG is also known for supporting the body’s natural production of SAMe, making it a clear choice for supporting normal mood balance.* Betaine, as TMG is also known, is important to liver health because it is able to donate methyl groups during phase 2 conjugation, allowing for the fat soluble or insoluble toxins to become more water soluble and thus better prepared for excretion.* These substances include homocysteine, heavy metals and excess neurotransmitters. When TMG does donate one of its own methyl groups, it deposits DMG (TMG with one less methyl group). This derivative supports neurological function, oxygen utilization, circulation and much more.*
Healthy methylation is a vital component to our overall health. By offering quality, active and bioavailable ingredients that support this process, even in the face of given SNPs that reduce MTHFR enzymatic activity, you can give your patients something more than a simple supplement regimen. You can give them peace of mind.
WHAT MAKES mETHYL Benefits FROM DAVINCI® UNIQUE?