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Glutamate Residue and Folic Acid Found in fortified foods, vitamin compounds and nutritional supplements, folic acid is the synthetic form of a water-soluble B vitamin known in its natural form as folate. Humans and other mammals are unable to synthesize folate within the body, and so must obtain this vitamin from dietary sources.

Folate is essential for health, since it supports cellular processes and DNA synthesis. Low blood levels of folate can lead to a variety of health issues. Women with low blood folate risk bearing children with neural tube defects. A folate deficiency is also associated with high levels of homocysteine in the blood, which causes inflammation and raises the risk of cardiovascular disease. Research has also investigated associations between low folate intake and cognitive problems, cancer and some psychiatric illnesses.

Natural sources of folate include a variety of fruits and vegetables, as well as organ meats, legumes, mushrooms and yeast. Folate from natural sources is most efficiently utilized by the body. But when the diet fails to supply adequate amounts of folate, supplementation, either from fortified foods or capsules, can help.

Folic acid, the synthetic form, is added to a variety of foods, including cereals, breads and other baked goods. Folic acid is also available as part of B-vitamin compounds or alone as a dedicated folic acid supplement. But folic acid is biologically inactive; it must be converted by the cells to a biologically active form called tetrahydrofolate so that the body can use it.

When folic acid is ingested, it exists in the body in a polyglutamate form. To convert folic acid to its usable form, tetrahydrofolate, conjugase, an enzyme found in the intestinal mucosa, must remove some of the glutamate residues. The removal of glutamate residues allows this form of folate to pass more easily into the bloodstream. It can then be reduced to tetrahydrofolate and stored in the cells, particularly in the liver. This process makes it available for supporting cell health and optimum functioning of the body.

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Soldiers May Suffer Brain Injury from IED Blasts Exposure to even one blast from an explosive device can cause long-term brain impairment in combat-zone soldiers, according to new research into the effects of blast wind on long-term memory and cognition.

Studies conducted by scholars from Boston University and New York Medical College, in partnership with the Veterans Affairs Boston Healthcare System, reveal that it can take only one incidence of exposure to an improvised explosive device, or IED, to cause not only traumatic brain injury but also chronic traumatic encephalopathy, a progressive brain disorder frequently seen in professional athletes such as boxers and football players.

Chronic traumatic encephalopathy (CTE) can only be diagnosed postmortem. This neurodegenerative disease is characterized by tau lesions, abnormal deposits of tau protein throughout the brain that are also implicated in the development of Alzheimer’s disease.

These deposits, appearing as neurofibrillary tangles and threads, cause psychiatric symptoms such as mood changes, as well as long-term memory impairment and learning disabilities.

Eventually the affected brain cells die, leading to dementia and ultimately death.

When the brain tissue of military personnel exposed to blasts in the field was compared to that of athletes with known repetitive concussive injuries, the incidence of CTE in both groups was similar. Working with blast physicists to determine the dynamics of brain injury from blast exposure, the Boston University team found that the blast wind from an IED, which can reach velocities of over 300 miles per hour, buffets the head with enough force to slam the brain against the skull. This impact triggers the swelling and bleeding characteristic of a traumatic brain injury.

The long-term cognitive impairment associated with CTE could be observed in as little as two weeks after soldiers experienced a single blast from an IED. These findings explain many of the psychological and behavioral problems so often seen in returning veterans, who may have faced repeated blast exposures during their tours. Many of these individuals exhibit symptoms of longterm cognitive impairment, mood changes and problems with other areas of brain functioning, often long after returning home.

This new understanding of the effect of even a single blast exposure on the brain may also lead to new ways to protect it from injury. Because brain injury from an IED blast appears to be caused by movement of the head, efforts to prevent injury focus on finding ways to keep the head immobile in situations where concussive force can impact the brain.

Chronic traumatic encephalopathy has no cure, and the effects of traumatic brain injury can last a lifetime. But, researchers point out, a better understanding of the devastating consequences of even a single exposure to an explosive blast can lead to improvements in the treatment and rehabilitation of affected soldiers. The discovery of the similarities between brain injured military personnel and athletes can lead to new ways to protect the brain -- on the battlefield as well as on the playing field.

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L u n a Bl u eSt u d i o s c ov e rphot o:NASA/ godda r d