Methylcobalamin, Cytokines, Immunoglobulins, Neurons

Advances in Autism Research
April 2010

Two studies have found that methylcobalamin (ie, methyl-B12) modulates immunity (1-2) in ways that may be beneficial in some children with autism. Indeed, at least two clinical studies have reported that methylcobalamin is beneficial for some autistic children (3-4). Studies describing cytokines in autism have a range of results that may be relevant to methylcobalamin's ability to modulate cytokines (eg, 5-19). Atypical levels of immunoglobulin levels have been found in autism (20-27), and these findings too may be relevant to methyl-B12's ability to modulate immunoglobulins (2). A newly published study elucidates methylcobalamin mechanisms within injured neurons (28). Given parental reports of mB12 efficacy (here), more high-quality basic and clinical research regarding methylcobalamin is needed.

References:

1. Effects of methylcobalamin (vitamin B12) on in vitro cytokine production of peripheral blood mononuclear cells
Yamashiki M, Nishimura A, Kosaka Y.
J Clin Lab Immunol. 1992;37(4):173-82.

Recently in Japan, one form of vitamin B12, methylcobalamin also known as methyl B12, has attracted the attention of physicians as a therapy for patients with rheumatoid arthritis. However, its immunological actions in vivo are still unknown. In this study, we induced the in vitro production of such cytokines as interleukin-6 (IL-6), interferon-gamma (IFN-gamma), and interleukin-1 beta (IL-1 beta) by adding various mitogens (phytohemagglutinin:PHA, concanavalin A: ConA, or pokeweed mitogen:PWM) as well as recombinant interleukin-2, and we investigated the effects of methyl B12 (final concentration, 8-8,000 ng/ml) on the production of these cytokines by peripheral mononuclear cells. As compared to the controls,IL-6 production induced by PHA and ConA on Day 4 of the culture was suppressed by an average 60-70% when methyl B12 (80-8,000 ng/ml) was added to the medium. IFN-gamma production decreased dose-dependently with methyl B12, i.e., it decreased to 46% of the control when this production was induced by rIL-2, and decreased to 56-66% when it was induced by mitogens. The effect of methyl B12 on IL-1 beta production on Day I of the culture was small. These findings indicate that methyl B12 suppresses mainly the cytokine production of T lymphocytes. Such suppressive effects as shown in the in vitro situation are expected to be expressed also in vivo in patients with rheumatoid arthritis, especially at articulation lesion sites.

2. Effects of methyl-B12 on the in vitro immune functions of human T lymphocytes.
Sakane T, Takada S, Kotani H, Tsunematsu T.
J Clin Immunol. 1982 Apr;2(2):101-9.

Studies were performed using an in vitro assay system to determine whether or not methyl-B12 could affect human T-cell function. When T cells were stimulated with phytohemagglutinin and allogeneic B cells, methyl-B12 did not enhance T-cell proliferation. In contrast, remarkable enhancing effects of methyl-B12 on the proliferative response to concanavalin A (Con A) and autologous B cells at suboptimal concentrations were observed, ranging from 0.1 to 10 micrograms/ml. Concentrations of methyl-B12 sufficient to enhance cellular proliferation were able to enhance the activity of helper T cells for immunoglobulin synthesis of B cells by pokeweed mitogen. Furthermore, the presence of methyl-B12 significantly potentiated the induction of suppressor cells in Con A-activated cultures. These results suggest that methyl-B12 could modulate lymphocyte function through augmenting regulatory T-cell activities.

3. Metabolic biomarkers of increased oxidative stress and impaired methylation capacity in children with autism
James SJ, Cutler P, Melnyk S, Jernigan S, Janak L, Gaylor DW, Neubrander JA.
Am J Clin Nutr. 2004 Dec;80(6):1611-7.
{free online}
http://www.ajcn.org/cgi/content/full/80/6/1611

BACKGROUND: Autism is a complex neurodevelopmental disorder that usually presents in early childhood and that is thought to be influenced by genetic and environmental factors. Although abnormal metabolism of methionine and homocysteine has been associated with other neurologic diseases, these pathways have not been evaluated in persons with autism. OBJECTIVE: The purpose of this study was to evaluate plasma concentrations of metabolites in the methionine transmethylation and transsulfuration pathways in children diagnosed with autism. DESIGN: Plasma concentrations of methionine, S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), adenosine, homocysteine, cystathionine, cysteine, and oxidized and reduced glutathione were measured in 20 children with autism and in 33 control children. On the basis of the abnormal metabolic profile, a targeted nutritional intervention trial with folinic acid, betaine, and methylcobalamin was initiated in a subset of the autistic children. RESULTS: Relative to the control children, the children with autism had significantly lower baseline plasma concentrations of methionine, SAM, homocysteine, cystathionine, cysteine, and total glutathione and significantly higher concentrations of SAH, adenosine, and oxidized glutathione. This metabolic profile is consistent with impaired capacity for methylation (significantly lower ratio of SAM to SAH) and increased oxidative stress (significantly lower redox ratio of reduced glutathione to oxidized glutathione) in children with autism. The intervention trial was effective in normalizing the metabolic imbalance in the autistic children. CONCLUSIONS: An increased vulnerability to oxidative stress and a decreased capacity for methylation may contribute to the development and clinical manifestation of autism.

4. Efficacy of methylcobalamin and folinic acid treatment on glutathione redox status in children with autism
James SJ, Melnyk S, Fuchs G, Reid T, Jernigan S, Pavliv O, Hubanks A, Gaylor DW.
Am J Clin Nutr. 2009 Jan;89(1):425-30.
{free online}
http://www.ajcn.org/cgi/content/full/89/1/425

BACKGROUND: Metabolic abnormalities and targeted treatment trials have been reported for several neurobehavioral disorders but are relatively understudied in autism. OBJECTIVE: The objective of this study was to determine whether or not treatment with the metabolic precursors, methylcobalamin and folinic acid, would improve plasma concentrations of transmethylation/transsulfuration metabolites and glutathione redox status in autistic children. DESIGN: In an open-label trial, 40 autistic children were treated with 75 microg/kg methylcobalamin (2 times/wk) and 400 microg folinic acid (2 times/d) for 3 mo. Metabolites in the transmethylation/transsulfuration pathway were measured before and after treatment and compared with values measured in age-matched control children. RESULTS: The results indicated that pretreatment metabolite concentrations in autistic children were significantly different from values in the control children. The 3-mo intervention resulted in significant increases in cysteine, cysteinylglycine, and glutathione concentrations (P < 0.001). The oxidized disulfide form of glutathione was decreased and the glutathione redox ratio increased after treatment (P < 0.008). Although mean metabolite concentrations were improved significantly after intervention, they remained below those in unaffected control children. CONCLUSION: The significant improvements observed in transmethylation metabolites and glutathione redox status after treatment suggest that targeted nutritional intervention with methylcobalamin and folinic acid may be of clinical benefit in some children who have autism. This trial was registered at (clinicaltrials.gov) as NCT00692315.

5. Low-grade endotoxemia in patients with severe autism.

Emanuele E, Orsi P, Boso M, Broglia D, Brondino N, Barale F, di Nemi SU, Politi P.
Neurosci Lett. 2010 Mar 8;471(3):162-5.

6. Differential monocyte responses to TLR ligands in children with autism spectrum disorders.
Enstrom AM, Onore CE, Van de Water JA, Ashwood P.
Brain Behav Immun. 2010 Jan;24(1):64-71.

7. Preliminary evidence of the in vitro effects of BDE-47 on innate immune responses in children with autism spectrum disorders.
Ashwood P, Schauer J, Pessah IN, Van de Water J.
J Neuroimmunol. 2009 Mar 31;208(1-2):130-5.

8. Elevated immune response in the brain of autistic patients.
Li X, Chauhan A, Sheikh AM, Patil S, Chauhan V, Li XM, Ji L, Brown T, Malik M.
J Neuroimmunol. 2009 Feb 15;207(1-2):111-6.

9. Altered gene expression and function of peripheral blood natural killer cells in children with autism.
Enstrom AM, Lit L, Onore CE, Gregg JP, Hansen RL, Pessah IN, Hertz-Picciotto I, Van de Water JA, Sharp FR, Ashwood P.
Brain Behav Immun. 2009 Jan;23(1):124-33.

10. Immune activation of peripheral blood and mucosal CD3+ lymphocyte cytokine profiles in children with autism and gastrointestinal symptoms.
Ashwood P, Wakefield AJ.
J Neuroimmunol. 2006 Apr;173(1-2):126-34.

11. Elevated cytokine levels in children with autism spectrum disorder.
Molloy CA, Morrow AL, Meinzen-Derr J, Schleifer K, Dienger K, Manning-Courtney P, Altaye M, Wills-Karp M.
J Neuroimmunol. 2006 Mar;172(1-2):198-205.

12. Spontaneous mucosal lymphocyte cytokine profiles in children with autism and gastrointestinal symptoms: mucosal immune activation and reduced counter regulatory interleukin-10.
Ashwood P, Anthony A, Torrente F, Wakefield AJ.
J Clin Immunol. 2004 Nov;24(6):664-73.

13. High nitric oxide production in autistic disorder: a possible role for interferon-gamma.
Sweeten TL, Posey DJ, Shankar S, McDougle CJ.
Biol Psychiatry. 2004 Feb 15;55(4):434-7.

14. Intestinal cytokines in children with pervasive developmental disorders.
DeFelice ML, Ruchelli ED, Markowitz JE, Strogatz M, Reddy KP, Kadivar K, Mulberg AE, Brown KA.
Am J Gastroenterol. 2003 Aug;98(8):1777-82.

15. Innate immunity associated with inflammatory responses and cytokine production against common dietary proteins in patients with autism spectrum disorder.
Jyonouchi H, Sun S, Itokazu N.
Neuropsychobiology. 2002;46(2):76-84.

16. Activation of the inflammatory response system in autism.
Croonenberghs J, Bosmans E, Deboutte D, Kenis G, Maes M.
Neuropsychobiology. 2002;45(1):1-6.

17. Proinflammatory and regulatory cytokine production associated with innate and adaptive immune responses in children with autism spectrum disorders and developmental regression.
Jyonouchi H, Sun S, Le H.
J Neuroimmunol. 2001 Nov 1;120(1-2):170-9.

18. Th1- and Th2-like cytokines in CD4+ and CD8+ T cells in autism.
Gupta S, Aggarwal S, Rashanravan B, Lee T.
J Neuroimmunol. 1998 May 1;85(1):106-9.

19. Plasma increase of interleukin-12 and interferon-gamma. Pathological significance in autism.
Singh VK.
J Neuroimmunol. 1996 May;66(1-2):143-5.

20. Family analysis of immunoglobulin classes and subclasses in children with autistic disorder.

Spiroski M, Trajkovski V, Trajkov D, Petlichkovski A, Efinska-Mladenovska O, Hristomanova S, Djulejic E, Paneva M, Bozhikov J.
Bosn J Basic Med Sci. 2009 Nov;9(4):283-9.

21. Reduced levels of immunoglobulin in children with autism correlates with behavioral symptoms.
Heuer L, Ashwood P, Schauer J, Goines P, Krakowiak P, Hertz-Picciotto I, Hansen R, Croen LA, Pessah IN, Van de Water J.
Autism Res. 2008 Oct;1(5):275-83.

22. Prevalence of autism spectrum disorders in relatives of patients with selective immunoglobulin A deficiency.
Santaella ML, Varela Y, Linares N, Disdier OM.
P R Health Sci J. 2008 Sep;27(3):204-8.

23. Plasma concentration of immunoglobulin classes and subclasses in children with autism in the Republic of Macedonia: retrospective study.
Trajkovski V, Ajdinski L, Spiroski M.
Croat Med J. 2004 Dec;45(6):746-9.

24. Increased serum albumin, gamma globulin, immunoglobulin IgG, and IgG2 and IgG4 in autism.
Croonenberghs J, Wauters A, Devreese K, Verkerk R, Scharpe S, Bosmans E, Egyed B, Deboutte D, Maes M.
Psychol Med. 2002 Nov;32(8):1457-63.

25. Brief report: immunoglobulin A deficiency in a subset of autistic subjects.
Warren RP, Odell JD, Warren WL, Burger RA, Maciulis A, Daniels WW, Torres AR.
J Autism Dev Disord. 1997 Apr;27(2):187-92.

26. Receptor inhibition by immunoglobulins: specific inhibition by autistic children, their relatives, and control subjects.
Cook EH Jr, Perry BD, Dawson G, Wainwright MS, Leventhal BL.
J Autism Dev Disord. 1993 Mar;23(1):67-78.

27. Childhood autism. Cerebrospinal fluid examination and immunoglobulin levels.

Young JG, Caparulo BK, Shaywitz BA, Johnson WT, Cohen DJ.
J Am Acad Child Psychiatry. 1977 Winter;16(1):174-9.

28. Methylcobalamin increases Erk1/2 and Akt activities through the methylation cycle and promotes nerve regeneration in a rat sciatic nerve injury model

Kiyoshi Okada et al.

Experimental Neurology 2010 222:191-203

Methylcobalamin is a vitamin B12 analog and is necessary for the maintenance of the nervous system. Although some previous studies have referred to the effects of methylcobalamin on neurons, the precise mechanism of this effect remains obscure. Here we show that methylcobalamin at concentrations above 100 nM promotes neurite outgrowth and neuronal survival and that these effects are mediated by the methylation cycle, a metabolic pathway involving methylation reactions. We also demonstrate that methylcobalamin increases Erk1/2 and Akt activities through the methylation cycle. In a rat sciatic nerve injury model, continuous administration of high doses of methylcobalamin improves nerve regeneration and functional recovery. Therefore, methylcobalamin may provide the basis for better treatments of nervous disorders through effective systemic or local delivery of high doses of methylcobalamin to target organs.

This document prepared by
Teresa Binstock
Researcher in Developmental & Behavioral Neuroanatomy
April 2010