New research from Tel Aviv University and MIT suggests that magnesium, a key nutrient for the functioning of memory, may be even more critical than previously thought. The multi-center experiment focused on a new magnesium supplement, magnesium-L-theronate (MgT), and found that the synthetic compound enhances memory or prevents its impairment in young and aging animals. The research was carried out over a five-year period and may have significant implications for the use of over-the-counter magnesium supplements.

In the study, published recently in Neuron, two groups of rats ate normal diets containing a healthy amount of magnesium from natural sources. The first group was given a supplement of MgT, while the control group had only its regular diet. Behavioral tests showed that cognitive functioning improved in the rats in the first group and also demonstrated an increase of synapses in the brain –– connective nerve endings that carry memories in the form of electrical impulses from one part of the brain to the other.

"We are really pleased with the positive results of our studies," says  co-author Dr. Inna Slutsky. "But on the negative side, we've also been able to show that today's over-the-counter magnesium supplements don't really work. They do not get into the brain."

"We've developed a promising new compound which has now taken the first important step towards clinical trials by Prof. Guosong Liu, Director of the Center for Learning and Memory at Tsinghua University and cofounder of Magceutics company," she says.

While the effects were not immediate, the researchers in the study were able to assess that the new compound shows improved permeability of the blood-brain barrier. After two weeks of oral administration of the compound in mice, magnesium levels in the cerebral-spinal fluid increased.

"It seems counterintuitive to use magnesium for memory improvement because magnesium is a natural blocker of the NMDA receptor, a molecule critical for memory function. But our compound blocks the receptor only during background neuronal activity. As a result, it enhances the brain's 'plasticity' and increases the number of brain synapses that can be switched on," says Dr. Slutsky.

"Our results suggest that commercially available magnesium supplements are not effective in boosting magnesium in cerebro-spinal fluid," she says. "Magnesium is the fourth most abundant mineral in the body, but today half of all people in industrialized countries are living with magnesium deficiencies that may generally impair human health, including cognitive functioning."

Before the new compound becomes commercially available, the researchers advise that people get their magnesium the old-fashioned way -- by eating lots of green leaves, broccoli, almonds, cashews and fruit. The effects on memory won't appear overnight, she cautions, but with this persistent change in diet, memory should improve, and the effects of dementia and other cognitive impairment diseases related to aging may be considerably delayed.



Citation: Slutsky et al., 'Enhancement of Learning and Memory by Elevating Brain Magnesium', Neuron, January 2010, 65(2), 165-177; doi: 10.1016/j.neuron.2009.12.026