Traumatic Brain Injuries
1) Seven of eight patients in a vegetative state regained consciousness after being treated with Sinemet.
Sinemet (levodopa-carbidopa) is a drug used to treat Parkinson’s
disease, a disease of the brain that leads to tremors and loss of coordination.
Eight patients who had been in a vegetative state for a mean of 104 days
following traumatic brain injuries were given Sinemet as part of a research
study. All of the patients showed some signs of improvement within 13 days.
Seven of the patients subsequently regained consciousness within a mean
time of 31 days.
Brain Research. 2004 Nov 5; 1026(1): 11-22.
2) New treatments to limit brain cell death following traumatic brain injury show promise.
Injury to any part of the body triggers an extremely complex reaction by
the body, which is only partially understood. It is known that some components
of the reaction may actually worsen the original injury. Swedish researchers
have recently confirmed that a particular protein (ERK) in nerve and brain
cells worsens the initial injury. They also found that two drugs (U0126
and S-PBN) known to have a protective effect on the brain following injury
reduced the activity of the ERK protein. The amount of brain atrophy in
experimental animals with TBI treated with either of the drugs was 60% less
than the atrophy in untreated animals. Use of the drugs in experimental
trials with people is being proposed.
Journal of Neurotrauma. 2004 September; 21(9): 1168-82
3) Cyclosporin A has a protective effect following experimental diffuse traumatic brain injury.
One of the harmful effects of traumatic brain injury is on a part of brain
cells that produces energy for the cells (the mitochondria). Cyclosporin
A, a drug already being used to prevent the body’s immune system from
rejecting organ transplants and to treat patients with auto-immune conditions,
was studied at the Medical College of Virginia as a possible treatment for
traumatic brain injury. The drug was administered either intravenously or
into the brain itself in laboratory animals following traumatic brain injury.
The researchers found a significant increase in the energy production of
brain cells in injured animals treated with cyclosporin A. Clinical trials
in people will be the next step in the study of Cyclosporin A as a treatment
Journal of Neurotrauma. 2004 September; 21(9): 1154-67.
4) In the future transplantation of neural progenitor cells may aid in the
recovery from traumatic brain injury.
In recent years scientists have discovered the existence of neural progenitor
cells (NPCs). These brain cells, which are found in people and animals of
all ages, are capable of dividing and changing into several different kinds
of brain cells, including neurons, oligodendrocytes, and astrocytes. Experiments
have been conducted in which NPCs were transplanted into the brains of mice
with traumatic brain injury. Mice with transplanted NPCs showed significant
improvement in motor abilities one week after transplantation and the results
were still present one year later. The mice also showed significant improvement
in spatial learning abilities. Trnasplantation of NPCs into people may one
day help people with TBIs recover from their injuries.
Brain Research. 2004 November 5; 1026(1): 11-22.
5) Magnesium has value in the treatment of traumatic brain injury.
Magnesium is a trace mineral needed by our bodies. Following traumatic
brain injury magnesium levels are reduced. Previous experiments have shown
that laboratory animals treated with magnesium following traumatic brain
injury had less severe short term motor and cognitive deficits than untreated
animals. Researchers at the University of Pennsylvania investigated whether
administering magnesium shortly after a TBI had long term (eight months
post injury) benefits for laboratory animals. They concluded that magnesium
did not show any benefit in improving learning deficits or loss of cortical
brain tissue. They did find, however, that there was a reduction in the
loss of brain tissue in the area of the brain called the hippocampus.
Journal of the American College of Nutrition. 2004 October; 23(5): 529S-533S.
6) Two hormones show promise in controlling the amount of brain swelling following traumatic brain injury.
Brain swelling following traumatic brain injury can lead to additional
brain cell death and brain damage. Swelling is caused by inflammation that
occurs in response to the injury. The inflammatory response is extremely
complex and involves both cells that are part of the body’s immune
system and chemicals, some of which are produced by the immune cells. Research
is being conducted into ways of lessening the inflammatory response following
TBI with the goal of reducing brain swelling. Two drugs that show promise
in reducing inflammation include the hormones progesterone and allopregnanolone.
The drugs appear to work by reducing the levels of chemicals associated
with the inflammatory response.
Experimental Neurology. 2004 Oct; 189(2): 404-12.
7) Transplantation of bone marrow cells improves healing from traumatic brain injury in laboratory experiments.
Cells in bone marrow develop into red and white blood cells. To study whether
bone marrow cells could increase new brain cells following traumatic brain
injury, groups of laboratory rats given bone marrow cells either intravenously
or directly into the brain were compared with untreated rats. Fifteen days
following the injections, the treated rat brains had significantly more
new brain cell development in the areas around the brain injury and in a
part of the brain called the subventricular zone, where cells that can develop
into new brain cells ordinarily are found. The treated rats also had greater
motor function than the untreated rats.
Neurosurgery. 2004 November; 55(5): 1185-1193.
8) Pituitary gland dysfunction is common in survivors of traumatic brain injury.
Irish investigators have confirmed in a study that it is common for people
with TBIs to have abnormally low functioning of their pituitary glands.
Because the pituitary affects many hormones, many different symptoms of
pituitary dysfunction can occur. It is important for low functioning of
the pituitary to be diagnosed because this condition can be successfully
Journal of Clinical Endocrinology and Metabolism. 2004 October; 89(10): 4929-36.
9) Drugs to stimulate the production of a chemical naturally produced in the brain may help in the treatment of people with traumatic brain injury.
Brain cells and nerve cells communicate with electrical and chemical signals.
British researchers have discovered that parts of the brain (the base of
the forebrain and the hippocampus) associated with a specific brain chemical
(acetylcholine) were less dense in people with ongoing symptoms of traumatic
brain injury than in people who had never had a traumatic brain injury.
This has led to an investigation as to whether drugs that stimulate the
brain to produce more of the naturally produced chemical will be helpful
in treating TBI.
Brain. 2004 November 17; [Epublication ahead of print].
10) Hyperbaric oxygen therapy is being studied as a treatment of traumatic brain injury.
“Hyperbaric” oxygen simply means oxygen that is given at pressures greater than atmospheric pressure, which is the pressure of the air we normally breathe. To achieve high pressures, a compression chamber is used. These chambers look like a miniature submarine and are built to withstand the high air pressure created inside them, which is where the patient is treated. Compression chambers were first used to treat divers with “the bends,” a condition that occurs when a diver ascends too rapidly and nitrogen compressed in the blood as a result of high underwater pressure expands too rapidly for the body to adapt.
Hyperbaric oxygen is now used to treat conditions other than those related
to diving. Australian researchers studied whether hyperbaric oxygen was
an effective treatment of TBI while patients were still in an intensive
care unit following injury. They found that the treatment did reduce the
risk of dying from the injury but did not find conclusive evidence that
it improved outcomes in patients who survived. They concluded that at present
the evidence was insufficient to support use of hyperbaric oxygen in the
treatment of TBI but was sufficient to support more studies.
Cochrane Database Systems Review. 2004 October; 18; (4): CD004609.
11) Verification of biomechanical methods employed in a comprehensive study of mild traumatic brain injury and the effectiveness of American football helmets.
Concussion, or mild traumatic brain injury, occurs in many activities, mostly as a result of the head being accelerated. A comprehensive study has been conducted to understand better the mechanics of the impacts associated with concussion in American football. This study involves a sequence of techniques to analyse and reconstruct many different head impact scenarios. It is important to understand the validity and accuracy of these techniques in order to be able to use the results of the study to improve helmets and helmet standards. Two major categories of potential errors have been investigated. The first category concerns error sources specific to the use of crash test dummy instrumentation (accelerometers) and associated data processing techniques. These are relied upon to establish both linear and angular head acceleration responses. The second category concerns the use of broadcast video data and crash test dummy head-neck-torso systems. These are used to replicate the complex head impact scenarios of whole body collisions that occur on the football field between two living human beings. All acceleration measurement and processing techniques were based on well-established practices and standards. These proved to be reliable and reproducible. Potential errors in the linear accelerations due to electrical or mechanical noise did not exceed 2% for the three different noise sources investigated. Potential errors in the angular accelerations due to noise could be as high as 6.7%, due to error accumulation of multiple linear acceleration measurements. The potential error in the relative impact velocity between colliding heads could be as high as 11%, and was found to be the largest error source in the sequence of techniques to reconstruct the game impacts. Full-scale experiments with complete crash test dummies in staged head impacts showed maximum errors of 17% for resultant linear accelerations and 25% for resultant angular accelerations.
J Biomech. 2006 Jul;38(7):1469-81.
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