Posts Tagged ‘MTHFR’
In continuing the series on the use of MB12 in autism, I am going to discuss the role of MTHFR and Glutathione. The last article showed that the MTHFR mutation is more common in people with ASD than in the regular population. The study listed below makes a correlation between MTHFR and low levels of Glutathione in the blood.
Experimental Biology 2005. April 2. San Diego . Abstract
Low plasma methionine, cysteine, and glutathione levels are associated with increased frequency of common polymorphisms affecting methylation and glutathione pathways in children with autism
S. Jill James, Stepan Melnyk, Stefanie Jernigan. Pediatrics, University of Arkansas for Medical Sciences, 1120 Marshall St. , Slot 512.40B, Little Rock , AR , 72202
Autism is a complex neurodevelopmental disorder that is thought to involve both genetic and environmental factors. The 10-fold increase in the prevalence of autism in the last 15 years is a major public health concern. Although abnormal thiol metabolism has been associated with other neurologic diseases, these pathways and related polymorphisms have not been evaluated in autistic children. Plasma levels of metabolites in methionine transmethylation and transsulfuration pathways were measured in 90 autistic and 45 control children using HPLC with electrochemical detection. Polymorphic variants in transcobalamin II (TCII), methylene- tetrahydrofolate reductase (MTHFR), methionine synthase reductase (MTRR), catecholamine-O-methyltransferase (COMT), and glutathione-S-transferase (GST) M1/T1 were evaluated in 233 autistic children and 183 controls. The results indicated that mean levels of methionine, cysteine, total glutathione, and the ratio of oxidized to reduced glutathione were significantly decreased among the autistic children. The frequency of MTHFR 677CT/1298AG heterozygosity, TCII 776GG, COMT 1947GG, and the GST M1/T1 double null genotype was increased in the autistic children relative to controls. We hypothesize that an increased vulnerability to oxidative stress (environmental and/or intracellular) may contribute to the development and clinical manifestations of autism.
So what does this mean for a patient? Glutathione is the body’s natural detoxification mechanism. Its job is to move ‘bad stuff’ out of the body. If you do not have enough, then harmful substances can accumulate and thus affect health; or if the toxins get too high, they can affect brain function. So how does glutathione affect the brain and what does this have to do with MB12? The following is a comment that Dr. Neubrander gives to his patients that (while a bit technical) may explain some of the processes involved.
According to the work of Dr. Richard Deth, methyl-B12 seems to work better in the brain, especially the cortex, than it does in the liver. This is probably because glutathione is very abundant in the liver but limited in the brain and methionine synthase in the brain is configured differently than in the liver. The methyl-B12-requiring form of the methionine synthase enzyme will only be active when there is enough glutathione around to synthesize methyl-B12. Of course the first step is the conversion of hydroxy-B12 to glutathionyl-B12. This occurs spontaneously when hyroxy-B12 and glutathione are simply mixed together. It’s limited only by the glutathione level, which is how nature designed it. So in tissues like the brain (neurons) where glutathione is scarce, methionine synthase activity will only be turned on when glutathione is adequate. Otherwise homocysteine will be continuously diverted toward glutathione synthesis. Thus methylation (i.e. D4 receptor activity) in the brain is only allowed to occur when there is enough glutathione. Things that lower glutathione (e.g. mercury) will therefore particularly lower methylation activity in the brain. SAM is also required for methyl-B12 synthesis, but does not seem to be as critical a limiting factor as glutathione.
At least theoretically, there could indeed be people for whom hydroxy-B12 might be better than methyl-B12. Making methyl-B12 available all the time removes the glutathione contingency for methionine synthase activity. It does guarantee that the D4 receptor phospholipid methylation mechanism will always be operating at better efficiency, despite lower glutathione levels, which is probably the main cognitive benefit of methyl-B12. However, allowing hydroxy-B12 to be converted to glutathionyl-B12 by glutathione may be important for other aspects of methylation. For example, consider DNA methylation. When methionine synthase stays turned off, homocysteine and SAH accumulate. The SAH will inhibit DNA methylation and “turn on” some genes that used to be silenced by methylation. Some of these genes may serve a useful role in combating oxidative stress. When methyl-B12 is given it will tend to lower homocysteine and SAH, which will tend to increase DNA methylation. Of course at this time we can only speculate about what genes might be involved, so this is just a theoretical perspective.
In general there is the possibility that too much methyl-B12 could be a problem, so finding the right dose and right duration of therapy for a given individual remains an important consideration. Hopefully in the near future there will be laboratory tests allowing us to discriminate between who needs methyl-B12 or hydroxy-B12 and who doesn’t.
Since May of 2002, Dr. Neubrander has been stressing the importance of MB12 for children on the spectrum. His initial finding of MB12′s benefits came by accident. In treating a non-verbal seven-year-old autistic patient, he decided to try a new form of B12 to help with some of the nutritional issues seen in this particular patient. One week later, in the middle of a huge storm that was hitting New Jersey, the parents of that child came unannounced to the office and ran down the hall shouting, “What was that you gave our child? He started speaking!” Thus history was made that day.
So why does MB12 help so many on the spectrum? This first series of blog posts will go through the various aspects of why MB12 is needed and how it helps. To start the series, I will be getting a little scientific but hopefully can explain it in such a way that an ordinary, non-medical person can understand.
First I am going to discuss the MTHFR mutation. I will probably be touching on this subject in future posts, but today I will start off with one study showing that people with ASD have a higher rate of mutation in the MTHFR gene, and then will follow with the doctor’s explanation of how this impacts persons with the mutation. Dr. Neubrander has written a preface for the study that we give our patients and I will begin with that comment, follow with the abstract, and end with an explanation of what this means in lay-terms.
JUNE 2009: Preface by Dr. Neubrander to the following published study – Please note that in my practice I have been testing most patients for MTHFR and homocysteine status. Though I have not yet officially tabulated the results from my patient population, I can definitely say by “seat-of-the-pants science” that the incidence of the MTHFR mutations, whether C677T or A1298C, are much higher than what was reported in this study. I can also say that most of my patients have at least one mutation; many have two. It has been my observation that children with the C677T homozygous (double) mutation are the most likely to respond to MB12 and with some of the best “initial intensities of response”. Children who have a single (heterozygous) mutation of the C677T allele or who have two single mutations on the two different alleles, C677T (heterozygous) and A1298C (heterozygous) or who have double mutations (homozygous) of the A1298 allele are the next most likely group of children to respond to MB12 injections. As a general rule, this group of children demonstrate responses fewer in number and of a lesser intensity when present. Children with a single (heterozygous) mutation of the A1298C allele represent the group of children whose responses, though present, are usually the fewest in number and of the least intensity. It is interesting to hypothesize why some of the best responders, both in number of responses and intensity of responses, have no MTHFR mutations.
Psychiatr Genet. 2009 May 13. [Epub ahead of print]
Aberrations in folate metabolic pathway and altered susceptibility to autism.
Mohammad NS, Jain JM, Chintakindi KP, Singh RP, Naik U, Akella RR.
a. Center for DNA Fingerprinting and Diagnostics
b.Institute of Child Health, Niloufer Hospital, Hyderabad, India.
OBJECTIVE: To investigate whether genetic polymorphisms are the underlying causes for aberrations in folate pathway that was reported in autistic children. BASIC METHODS: A total of 138 children diagnosed as autistic based on Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria and Autism Behavior Checklist scoring and 138 age and sex matched children who are nonautistic were tested for five genetic polymorphisms, that is, cytosolic serine hydroxyl methyl transferase (SHMT1 C1420T), methylene tetrahydrofolate reductase (MTHFR C677T and MTHFR A1298C), methionine synthase reductase (MTRR A66G), methionine synthase (MS A2756G) using PCR-restriction fragment length polymorphism methods. Fisher’s exact test and logistic regression analysis were used for statistical analyses. RESULTS: MTHFR 677T-allele frequency was found to be higher in autistic children compared with nonautistic children (16.3 vs. 6.5%) with 2.79-fold increased risk for autism [95% confidence interval (CI): 1.58-4.93]. The frequencies of MTRR 66A allele (12.7 vs. 21.0%) and SHMT 1420T allele (27.9 vs. 45.3%) were lower in autistic group compared with nonautistic group with odds ratios 0.55 (95% CI: 0.35-0.86) and 0.44 (95% CI: 0.31-0.62), respectively, indicating reduced risk. MTHFR 1298C-allele frequency was similar in both the groups (53.3 vs. 53.6%) and hence individually not associated with any risk. However, this allele was found to act additively in the presence of MTHFR 677T allele as evidenced by 8.11-fold (95% CI: 2.84-22.92) risk associated with MTHFR 677CT+TT/1298AC+CC genotypes cumulatively. CONCLUSION: MTHFR C677T is a risk factor, whereas MTRR A66G and SHMT C1420T polymorphisms reduce risk for autism. MTHFR A1298C acts additively in increasing the risk for autism.
So what does this mean? Of what importance is MTHFR to ASD? I am including a comment we give our patients to explain in simpler terms what MTHFR does.
The way that the MTHFR enzymatic defect fits into this whole scenario is that folic acid family members from food must travel down a biochemical pathway and present itself to the enzyme MTHFR [methyltetrahydrofolate reductase]. This enzyme then will catalyze the biochemical reaction that allows the precursor “unmethylated” folic acid molecule to grab onto extra hydrogen atoms and now become a “methylated” folic acid molecule [5-methyltetrahyrdofolic acid]. It is the methyl group from this methylated folic acid molecule that can now donate the methyl group to “rabbit B12″ — the plain ole’ ordinary B12 that comes from food or supplements – so that rabbit B12 now becomes “methyl”-B12. It is this methyl-B12, whose methyl group originated from the “MTHFR processing plant”, that will react with the enzyme methionine synthase to go on to donate this same methyl group to homocysteine to now become “methylated homocysteine” whose “other name” is methionine. It is this methionine that moves on to eventually donate this same methyl group to the brain to make proper functioning RNA, DNA, neurotransmitters, speech and language molecules [creatine], and nervous signal synchronization molecules [phospholipids]. Once this methyl group has been donated, the “methyl carrier molecule — metabolic smoke” eventually winds up to become homocysteine again. Once homocysteine is formed, it acts like a traffic cop deciding to send traffic to the left or to the right. “About” half the time homocysteine goes back to get another methyl group from “the next” methyl-B12 that shows up as the process described above repeats itself. “About” the other half of the time homocysteine decides to become glutathione which is the body’s major intracellular antioxidant and one of the body’s major way to detoxify many types of poison, only one of which is mercury.
The MTHFR enzyme has legs just like we have legs. We call our legs “left leg — right leg”. On both legs we are supposed to have ankles and knees. MTHFR’s legs have funny names. The name of one leg is C677T and the name of the other leg is A1298T. The name of MTHFR’s ankles and legs are C and T or A and T. Now here’s what’s happening. When we try to run, we do very well if we have two legs with knees and ankles. If we have an amputation of one ankle, we can still get around but we will definitely be slowed down. If we have an amputation above the knee, we will still be able to get around but much, much slower. If we had an amputation of a knee or ankle on the other leg, once again we would get around much, much slower. So it is with the ankles and legs on the MTHFR enzyme. If there is a single mutation, called heterozygous, one of the legs will have been amputated at the ankle. It there is a double mutation on the same leg, called homozygous, that leg will have been amputated above the knee. Combinations of heterozygous and homozygous mutations [analogous here to "amputations"] can occur.
What the developing research is finding is that mutations of the MTHFR enzyme occur quite frequently in children on the autistic spectrum. Therefore, as you can now see, these children will have a “slowed ability” to produce the methylated folic acid molecules that are required to form “enough” methyl-B12 at the rate necessary to make “brain things” and to make “detoxification things”. Therefore, in order to bypass this defect, methyl-B12 must be administered on a continual steady-state basis. This is the reason that injectable methyl-B12 into the subcutaneous tissue accomplishes this goal. By being in the subcutaneous tissue it slowly leaches out and provides a continual supply of “just a little bit” of methyl-B12 to be available for methionine synthase to use to recycle homocysteine.