Aging, Author Interviews, Autism, Mental Health Research, PLoS, Schizophrenia / 25.01.2016
Brain Levels of Vitamin B12 Decreased in Aging, Autism and Schizophrenia
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Dr. Richard Deth[/caption]
MedicalResearch.com Interview with:
Dr. Richard Deth PhD
Professor of Pharmacology
Department of Pharmaceutical Sciences
Nova Southeastern University
Medical Research: What is the background for this study?
Dr. Deth: Vitamin B12 plays a crucial role in regulating and promoting methylation reactions (the attachment of a carbon atom to molecules), including DNA methylation. Recent research has identified methylation of DNA and consequential changes in gene expression as crucial factors in brain development, as well as in memory formation and maintenance of brain function during aging. More specifically, the cause(s) of neurodevelopmental disorders such as autism remain obscure, although numerous studies have demonstrated oxidative stress and low plasma levels of the antioxidant glutathione (GSH) in autism.
Medical Research: What are the main findings?
Dr. Deth: We found that brain levels of vitamin B12, especially the methylation-regulating form known as methylB12, decrease significantly with age, even though blood levels don’t show a similar decrease. Importantly, much lower levels of methylB12 were found in subjects with autism and schizophrenia compared to normal subjects of a similar age. Animal studies showed that impaired GSH formation is associated with decreased brain B12 levels.
Dr. Richard Deth[/caption]
MedicalResearch.com Interview with:
Dr. Richard Deth PhD
Professor of Pharmacology
Department of Pharmaceutical Sciences
Nova Southeastern University
Medical Research: What is the background for this study?
Dr. Deth: Vitamin B12 plays a crucial role in regulating and promoting methylation reactions (the attachment of a carbon atom to molecules), including DNA methylation. Recent research has identified methylation of DNA and consequential changes in gene expression as crucial factors in brain development, as well as in memory formation and maintenance of brain function during aging. More specifically, the cause(s) of neurodevelopmental disorders such as autism remain obscure, although numerous studies have demonstrated oxidative stress and low plasma levels of the antioxidant glutathione (GSH) in autism.
Medical Research: What are the main findings?
Dr. Deth: We found that brain levels of vitamin B12, especially the methylation-regulating form known as methylB12, decrease significantly with age, even though blood levels don’t show a similar decrease. Importantly, much lower levels of methylB12 were found in subjects with autism and schizophrenia compared to normal subjects of a similar age. Animal studies showed that impaired GSH formation is associated with decreased brain B12 levels.
Dr. Zoltan Sarnyai[/caption]
MedicalResearch.com Interview with:
Zoltan Sarnyai, M.D., Ph.D.
Associate Professor of Pharmacology
Head, Laboratory of Psychiatric Neuroscience
Australian Institute of Tropical Health and Medicine (AITHM)
Comparative Genome Centre
Centre for Biodiscovery and Molecular Development of Therapeutics
James Cook University
Townsville, Australia
Medical Research: What is the background for this study?
Dr. Sarnyai: Schizophrenia has long been conceptualized as a disease contributed by the increased activity of the neurotransmitter system that provides dopamine for the brain. All clinically used antipsychotic drugs inhibit dopamine transmission in the brain by blocking dopamine receptors. These drugs have only a limited efficacy on a certain set of symptoms associated with schizophrenia. More recent research has uncovered that abnormal glucose and energy metabolism in the brain may contribute in the development of schizophrenia. This is not altogether surprising considering that our brain is using a disproportionately high amount of glucose to fuel neurotransmission (cell-to-cell communication in the brain), to maintain normal electrical activity of nerve cells and to deal with damaging free oxygen radicals. Therefore, even relatively small changes in the machinery that is required to provide energy for the brain cells can have very significant impact on brain function. In fact, recent studies have identified altered expression of genes and proteins that are responsible for enzymatic breakdown of glucose and proper handling of the metabolites to create the energy-rich molecule ATP. In addition, recent research shows decreased number and impaired function of the mitochondria, the powerhouses of the cell, in the brain of individuals with schizophrenia.
These recent results that show abnormal energy metabolism in schizophrenia raise the possibility of targeting metabolic pathways for therapeutic benefit in this condition. Ketogenic diet provides and alternative source of energy to the brain through fatty acids. Furthermore, since this diet is very low in carbohydrates, almost all the energy needs of the cells comes from breaking down fat (fatty acids) as opposed to glucose. This can circumvent the classic glucose metabolic pathways that maybe impaired in the disease. Also, breaking down fatty acids produces 40% more of the energy-rich molecule ATP than breaking down the carbohydrate glucose. Altogether, ketogenic diet may provide extra energy and can help neurotransmission in the brain, leading to the improvement of neurobiological processes underlying schizophrenia.
Dr. Vonberg[/caption]
MedicalResearch.com Interview with:
Frederick W. Vonberg, MA, MBBS
Research Fellow in Neurocritical Care
Boston Children's Hospital and Harvard Medical School
Medical Research: What is the background for this study? What are the main findings?
Response: An association between schizophrenia and epilepsy has long been suspected, ever since people noticed similarities in some aspects of the presentation of the two conditions, and in their epidemiology. For example, people with epilepsy are thought to be more at risk of developing schizophrenia. Furthermore, a psychosis resembling schizophrenia can characterize some forms of 






