A proposed link between aging, autism, and oxidation

March 4, 2013 by Angela Herring, Northeastern University
Professor Richard Deth’s research on methionine synthase was recently published in the journal PLOS ONE. Credit: Richard Deth

Like any factory, the body burns oxygen to get energy for its various needs. As a result, detrimental byproducts are released and our cells try to clean up shop with antioxidants. But as we age, this process becomes a losing battle.

"Oxidation inexorably moves us along toward an oxidized state," said professor Richard Deth. "You have to deal with it progressively."

One option is to slow down the synthesis of new proteins, a process that requires energy. Indeed, as we age, we produce fewer new proteins, which explains why our capacity for learning and healing suffer as we grow old.

Since every protein originates from instructions in the DNA, protein synthesis can be slowed down by turning off particular genes. A process called epigenetic regulation accomplishes the task by adding molecular tags on top of the genome. The protein methionine synthase regulates this process. But what regulates methionine synthase? Oxidation.

"This enzyme is the most easily oxidized molecule in the body," said Deth, whose research on the subject was recently published in the journal . The senior author for the study, Christina Muratore, received her doctorate in pharmaceutical sciences from Northeastern in 2010.

Whenever the body is under oxidative stress, Deth explained, methionine synthase, or MS, stops working. He and his team hypothesized that MS plays an important regulatory role in aging and that it might be impaired in autism, which Deth has connected to unchecked oxidative stress in previous research.

To examine their hypothesis, the researchers looked at postmortem samples across the , with subjects as young as 28 weeks of to as old as 84 years. They measured the levels of a molecule called MS mRNA, which transcribes the for methionine synthase into actual protein.

As the subjects aged, their brain tissue showed lower levels of MS mRNA. But, surprisingly, the levels of the protein itself remained constant across the lifespan.

Deth and his colleagues suspect that this observed decrease in MS mRNA over our lives may act as a check in the system to save energy that we no longer have in plentiful supply and to slow down oxidative stress. "One way that the system can guard against too much protein synthesis is to restrict the amount of mRNA," Deth said.

The team also compared MS protein and mRNA levels between samples from autistic and normally developing subjects. Autistic brains had markedly less MS mRNA than the control samples but similar protein levels. Additionally, the age-dependent trend seen in normally developing brains was not mimicked among the autistic sample.

If decreased MS does mean decreased protein production, it's no big deal for adults who don't need to make new proteins as often. But for the developing brain, new proteins are critical. "Your capacity for learning might be prematurely reduced because metabolically you can't afford it," Deth suggested.

While the results are preliminary and will benefit from repeated studies and more investigation, Deth's findings add to a growing body of evidence linking both aging and autism to oxidative stress.

Explore further: New mechanism in the regulation of human genes

More information: www.plosone.org/article/info%3 … journal.pone.0056927

Related Stories

New mechanism in the regulation of human genes

July 14, 2011
Scientists at the Technical University of Munich and the Helmholtz Zentrum Muenchen and along with their colleagues from the European Molecular Biology Laboratory (EMBL) in Heidelberg and the Centre for Genomic Regulation ...

Recommended for you

Forces from fluid in the developing lung play an essential role in organ development

January 23, 2018
It is a marvel of nature: during gestation, multiple tissue types cooperate in building the elegantly functional structures of organs, from the brain's folds to the heart's multiple chambers. A recent study by Princeton researchers ...

Anemia discovery offers new targets to treat fatigue in millions

January 22, 2018
A new discovery from the University of Virginia School of Medicine has revealed an unknown clockwork mechanism within the body that controls the creation of oxygen-carrying red blood cells. The finding sheds light on iron-restricted ...

More surprises about blood development—and a possible lead for making lymphocytes

January 22, 2018
Hematopoietic stem cells (HSCs) have long been regarded as the granddaddy of all blood cells. After we are born, these multipotent cells give rise to all our cell lineages: lymphoid, myeloid and erythroid cells. Hematologists ...

How metal scaffolds enhance the bone healing process

January 22, 2018
A new study shows how mechanically optimized constructs known as titanium-mesh scaffolds can optimize bone regeneration. The induction of bone regeneration is of importance when treating large bone defects. As demonstrated ...

Researchers illustrate how muscle growth inhibitor is activated, could aid in treating ALS

January 19, 2018
Researchers at the University of Cincinnati (UC) College of Medicine are part of an international team that has identified how the inactive or latent form of GDF8, a signaling protein also known as myostatin responsible for ...

Bioengineered soft microfibers improve T-cell production

January 18, 2018
T cells play a key role in the body's immune response against pathogens. As a new class of therapeutic approaches, T cells are being harnessed to fight cancer, promising more precise, longer-lasting mitigation than traditional, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.