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Study under review: Behavioral and cognitive effects of the N-methyl-d-aspartate receptor co-agonist d-serine in healthy humans: Initial findings
Introduction
The science of biology has a long, proud history of progressing by breaking things. For example, a chemical that knocks out brain function is now starting to tell us about how the brain functions.
Ketamine was first used as a high-dose dissociative anesthetic, first tested in a prison population in the mid-1960s[1]. Thirty years later[2], it was used at lower doses to uncover some interesting information about how the brain works. Ketamine binds to a glutamate receptor in the brain known as the N-methyl-D-aspartate receptor (NMDAR), and reduces its activity. When the receptor was blocked with ketamine in the brains of healthy people, symptoms related to schizophrenia were observed, in addition to impaired cognition, which implies that the NMDAR may play a role in psychiatric and cognitive disorders.
If blocking the NMDAR induced schizophrenia-like symptoms, then perhaps stimulating it could help reduce symptoms of schizophrenics. This hypothesis has been tested, and a recent meta-analysis[3] found that several compounds that increase the function of the NMDAR show promise in helping to treat schizophrenia. One of these compounds is D-serine, an enantiomer (mirror image) of L-serine, one of the amino acids used as a building block of proteins.
Who and what was studied?
What were the findings?
What does the study really tell us?
The big picture
Frequently Asked Questions
What should I know?
Other Articles in Issue #05 (March 2015)
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Can you go too nutty over pistachios?
These researchers expected nutrient-packed pistachios to boost endurance, but found surprising results.
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Sex matters.
An under-discussed weakness of biomedical research is the lack of focus on women.
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Fish oil or snake oil?
Most people wouldn’t take rancid fish oil, yet it’s fairly likely to happen.
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A regimented nutrition strategy for marathoners
Some marathon runners go by “feel” when it comes to fluid and carb intake, which may worsen performance.
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Beating high blood pressure with beets
Previously demonized in the form of nitrate food preservatives, nitrates are now being researched for heart disease protection.
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Fighting back against food allergies with fish oil
Fish oil may help combat food allergies, as tested in this animal study looking at peanut and whey allergy.
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Metabolic chamber of secrets: effects of protein on metabolism when overeating
This tightly-controlled metabolic chamber study explored how protein affects energy expenditure during overfeeding.
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One meal, two meal, three meal, more?
While there’s been a lot of research on meal frequency and dieting, no one has summarized all the data until now.
- Interview: Dr. Shawn J. Green, PhD
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Interview: Adel Moussa
This soon-to-be NERD reviewer is interviewed about all things nutrition research.