Glutathione and Methylation

In the simplest terms, maintaining life can be viewed as the ability to resist oxidation. Oxygen is essential to life, but oxygen is like fire. It can do severe damage unless controlled by antioxidants, known as “reducing” molecules. We must balance reduction and oxidation: better known as redox: the fundamental challenge of life. What’s great about that word redox, is that it shows that they are profoundly linked and that we need both. Once you understand this relationship, it leads to all kinds of new insights.

The first is that, from the very moment of conception, life can be sparked by the unique redox environment created when a sperm fertilizes an egg. The sperm is extremely rich in proteins containing the mineral selenium, which is a potent reducing agent for glutathione, the master antioxidant molecule in cells. The egg, on the other hand, is very rich in glutathione. Bring these two potent antioxidant strategies together, and you create an exceptionally reduced cell that can initiate life and promote development using the power of redox. That reducing power provides a metabolic spark as new life begins its journey, allowing the rapidly dividing cells to safely maintain a high rate of oxidation. The same metabolic challenge continues as the embryo develops. The entire nervous system and the shaping of gene activity are profoundly influenced by this redox balance as well. Aging is essentially a process of gradual oxidation, and our health as we age depends on successfully quenching that oxidation.

Finally, innumerable diseases are linked to high levels of oxidation and low levels of glutathione, such as: schizophrenia to major depression, autism, chronic fatigue syndrome, fibromyalgia, and most chronic autoimmune and chronic inflammatory diseases. So let’s start with glutathione.

How do we make this critical antioxidant, glutathione?

The answer is a single word: cysteine. You can get cysteine from the diet, in meat, eggs, garlic, onions, red pepper, broccoli and other foods. Cells in the gut lining, aided by transporter molecules, will bring it into the body. However, and this is a very important point, both gluten (found in grains such as wheat) and casein (milk protein) can inhibit the uptake of cysteine. Why is it that so many children with autism, or adults with autoimmune disorders, do better when they eliminate wheat and milk from their diet? I personally think it’s due to a redox mechanism.

How do two of our most popular foods inhibit uptake of such an important protein?

Both casein and gluten are broken down into certain peptides that are relatively stable. The protein casein is broken into casomorphins. The “morphins” are so named because, like morphine, they act on the opiate receptors. The most famous one, beta casomorphin 7 (BCM7), has seven amino acids. Our recent research shows that BCM7 first stimulates the uptake of cysteine, but then inhibits it. However, the human BCM7 is markedly different than bovine BCM7 from the cow. It turns out that the BCM7 from a cow inhibits cysteine at least twice as much as the BCM7 from a human mother. The implications for health are profound if you start thinking about formula feeding and all the dairy products from cows in our diet. Breastfeeding is clearly regulating the redox system of newborns. A diet high in dairy from cows can promote a decrease in our antioxidant capacity, our ability to make enough glutathione.

Similarly, the protein in gluten is known as gliadin, and it also creates a seven amino acid peptide, like BCM7. We already know that gliadin can trigger celiac disease, and can also lead to gluten intolerance and sensitivity. This suggests that these problems reflect the ability of gluten peptides to inhibit cysteine uptake, perhaps contributing to chronic inflammation, although we have more to learn about that. Of course, not everybody who eats diary or wheat has poor antioxidant capacity. There are probably genetic vulnerabilities that bring some people closer to a critical point for oxidative stress, while for others it is a non-issue. Overall, though, this is an issue to consider in any chronic inflammatory disease or neuro-immune disease.

There is another way to make glutathione besides cysteine from the diet.

Your body can take homocysteine and convert it back to cysteine. Homocysteine is a metabolite of the essential amino acid methionine, and elevated levels have been associated with vascular disease. Homocysteine is created when methionine donates its methyl group to another molecule in a process known as methylation.

Methylation is a fundamental process of life which is intimately linked to redox status. In chemistry, a methyl group is a hydrocarbon molecule, or CH3. When a substance is methylated, it means that a CH3 molecule has been added to it.

Methylation can regulate gene expression, protein function, even RNA metabolism. It can suppress viruses, even latent viruses or cancer viruses we are born with and can help us handle heavy metals. In the liver in particular, methylating a toxin helps change it to a form of the compound that can be more easily processed and excreted.

Methylation is an extremely broad and fundamental action that nature uses to regulate all kinds of processes. I find it fascinating by the way it regulates epigenetic changes (changes to gene expression that occur because of environmental factors) by affecting how DNA unravels during development. Some changes can be permanent for the whole lifespan and can even be passed down as many as three generations. That shows that the environment, through the process of methylation, can be quite a profound influence. There are 150-200 methyl transferase enzymes, and each enzyme can methylate multiple targets. So you can imagine methylation as a spider’s web within each cell, and that web branches out in many directions.

Methylation and glutathione are very tightly intertwined. There is a critical metabolic intersection where cells must decide to either make more glutathione, or support more methylation. The overall balance between these two options is crucial to health, and this occurs with homocysteine. When methionine gives away its methyl group, we’re left with homocysteine. And the body has to decide, should homocysteine be methylated, and go back into methionine, or should it be converted into cysteine, so that the body can make more of the antioxidant glutathione? This fundamental decision is made again and again by the body, and the overall balance is crucial to health. Too little glutathione and we will end up with free radical, oxidative damage. Not enough methylation, and many genes and viruses will not be properly regulated. Excess homocysteine, and the risk of vascular disease goes up.

It’s important to understand that multiple factors impinge on the same system. What’s so important here is that the glutathione antioxidant system is a common target for so many different environmental toxins and infections. Every single one of them impinges on the glutathione system. It’s not that each molecule of mercury or lead picks off one glutathione molecule. No. It’s that in general, environmental assaults inhibit the enzymes that are responsible for keeping the glutathione in its reduced antioxidant state, where it can do its job. The potent ability of mercury to inhibit selenium containing enzymes is a good example.

Obviously, some people sail through these stressors and remain healthy, while others stumble and fall. There are nutrients that more vulnerable people might find useful to supplement to help shore up the methylation/glutathione process.

Though many molecules and nutrients are important, the active forms of vitamin B12 (adenosyl B12 and methyl B12) and the active form of folate (methylfolate) are essential to this process. Once you have the raw material to make glutathione or to methylate, you need cofactors like methylfolate and methyl B12 to complete the process. If we don’t make enough of these active forms, we will not be able to smoothly and fluidly shift between methylation and glutathione.

Nature allows, and even encourages, genetic variation, and the bottom line is that some people have genetic variations that render this process less functional. Even with a less functional genetic legacy, you might be fine if you are not stressed by the environment—in particular by chronic infections or toxic assaults. Stress brings out limitations in genes that otherwise are latent and not problematic. That’s a general truth. So yes, with proper testing by a doctor to see if there is a functional deficiency, supplementation with active forms can help.

What do the active forms of B12 do for methylation and glutathione synthesis?

First, I should point out that we ourselves cannot make B12, also known as cobalamin. Bacteria make it for us, and since vegetables don’t carry those bacteria, vegans can be deficient in B12. There are several natural forms of B12 which need to be converted into the active forms, adenosylB12 and methylB12. CyanoB12, the form in most vitamin supplements, is not active and is less useful than the active forms for treating deficiency states. Glutathione itself is needed for converting other forms of B12 to the active forms. Indeed, there is a type of cobalamin called glutathionylcobalamin that is an intermediate for making the active forms.

There are two enzymes in the human body that require active B12 as a cofactor. One is called methylmalonyl CoA mutase, and it needs adenosyl B12. It is an enzyme that is necessary for the mitochondria—the energy powerhouse of your cell—to function. The other enzyme that requires active B12 is the enzyme methionine synthase, which requires methyl B12.
Methyl B12 is constantly recycled. It donates its methyl group to homocysteine, which then turns into methionine. Once B12 is missing its methyl group, it needs to get a fresh one. And that’s where methylfolate comes in. Methylfolate is in essence a methyl donor for methionine synthase. That’s its job in life. It is the only molecule than can donate a methyl group to B12. Once it does that, the rest of the folate is available to go out and support all kinds of other reactions in the body that need plain folate.

So what happens when we don’t have enough methyl B12?

When your level of methylB12 is low, homocysteine builds up and this can have adverse health effects. High homocysteine levels in the blood reflect low activity of the enzyme methionine synthase, and this has been linked to an increased risk of atherosclerosis and coronary artery disease. It is also well known that homocysteine levels are increased in Alzheimer’s disease, which suggests a role for impaired methylation in this neurodegenerative disorder. Of course low B12 levels are classically associated with pernicious anemia and with peripheral neuropathy.

What happens when you don’t have enough methylfolate?

Low levels of folate are also classically associated with anemia, heart disease, fetal abnormalities such as spina bifida, as well as neuropathies and these have been specifically linked to a deficiency in methylfolate. In addition, recognition of the important role of methylfolate and vitamin B12 in supporting D4 dopamine receptor methylation links their deficiency to impaired attention such as attention-deficit hyperactivity disorder (ADHD). People with genetic polymorphisms in the enzyme that makes methylfolate are particularly vulnerable to a deficiency.

In addition to vitamin B12 and methylfolate, there are several other nutritional supplements whose actions are critical for redox and methylation pathways. N-acetylcysteine (NAC) provides a supplementary source of cysteine. NAC can cross into the cell cytoplasm where the cysteine is released and allowed to promote glutathione synthesis. SAMe is an active, methyl-donating derivative of the essential amino acid methionine, and during oxidative conditions its levels may be low, due to low methionine synthase activity. SAMe has also shown particular benefit in treating depression. The glutathione antioxidant system is a common target for so many different environmental toxins.  Every single one of them impinges on the glutathione system, and their effects are additive.

Source: www.drelenamorreale.com

Gluten-free / Casein-free dietary intervention:

Parents, support groups and several clinical studies report improvement in behavioral symptoms when autistic children are treated with a gluten-free/casein-free dietary intervention. Opiod derivatives of these food products, namely β-casomorphin (β-CM) and gliadinomorphin (GM) are absorbed from a “leaky gut” and may activate opiate receptors in brain. Morphine has been linked with oxidative imbalances during the development of addiction, and oxidative stress is believed to be a significant etiological factor for autism. We therefore hypothesized that opiates and food-derived opiate peptides might promote oxidative stress in neurons, leading to exacerbated behavioral symptoms. 

Objectives: 

1. To observe the acute and chronic effects of morphine and food-derived opiate peptides, as well as the opiate antagonist naltrexone, on cysteine uptake in cultured human neuronal cells.
2. To measure the effect of these drugs on cellular levels of sulfur-containing metabolites, including glutathione (GSH), a major antioxidant.

Methods:

Cellular [³⁵S]-Cysteine Uptake:

SH-SY5Y neuroblastoma cells were grown to confluence in six-well plates in α-MEM media containing 10% FBS and 1% penicillin-streptomycin. Cells were pre-treated with drugs for the specified time and [³⁵S]-cysteine uptake was measured. Non-transported [³⁵S]-cysteine was subtracted from total CPM for each sample and values were normalized to protein content.

HPLC Determination of Intracellular Thiols:

SH-SY5Y cells were pre-treated with drugs prior to addition of ice-cold perchloric acid. After sonication, centrifugation and filtration, the protein-free cell extract was analyzed via HPLC with electrochemical detection to measure thiol levels. Results were normalised to protein content.

Results:

Acute treatment with morphine decreased [³⁵S]-cysteine uptake by 70% (p<0.001), while β-CM and GM decreased uptake by 40% (p<0.05). Naltrexone blocked both of these effects, indicating involvement of opiate receptors. Long-term treatment with each of the opiates caused a complex pattern of inhibition and recovery of [³⁵S]-cysteine uptake activity, ultimately resulting in a sustained inhibition at 24 and 48 hrs.

β-CM and GM acutely lowered the cellular glutathione level (52% and 62%, respectively), while the level of homocysteine was acutely increased (50% and 44%, respectively). Glutathione levels recovered during the ensuing 8 hrs, although homocysteine levels decreased. Both glutathione and homocysteine levels were reduced at 24 and 48 hrs.

Together these results indicate that opiates acutely inhibit cysteine uptake in neuronal cells, resulting in an increase of homocysteine transsulfuration to cysteine and glutathione. However, this pathway is gradually exhausted, leading to decreased levels of intracellular levels of thiol metabolites, including glutathione. The long-term decrease in glutathione can contribute to oxidative stress.

Conclusions:

This is the first study to demonstrate inhibitory effects of food-derived opiod peptides on redox status and provides mechanistic support for the “Gut-Brain Hypothesis”. It reveals a rationale for the beneficial effect of a GF/CF dietary intervention in the treatment of autistic children, and may have general relevance for inflammatory bowel disorders in which gluten and/or casein intolerance plays a role.

Source: www.imfar.confex.com