New research into
how the ketogenic diet works to reduce and prevent seizures in children
with difficult-to-control epilepsy has been presented to the annual
meeting of the Society for Neuroscience.
high-fat calorie-restricted diet has been used for nearly 100 years to
try and prevent seizures in children whose epilepsy is unresponsive to
drugs. However, the researchers state that doctors have not really
understood exactly why the diet works. New studies by a research team
at Emory University School of Medicine
show that the diet alters genes involved in energy metabolism in the
brain, which in turn helps stabilise the function of neurons.
Emory research team found, as had others, that rats fed the ketogenic
diet slowly develop a resistance to seizures over one to two weeks, in
contrast to rats treated with conventional anti-epileptic drugs.
research team first eliminated the possibility that the ketogenic diet
might cause enhanced production of GABA, a chemical messenger in the
brain that helps limit seizure activity. They found that GABA levels in
the hippocampus were unchanged with the ketogenic diet. To test whether
energy reserves in hippocampal neurons were enhanced with the ketogenic
diet, they counted the number of energy "factories" (or mitochondria)
within cells. They found that ketogenic diet treatment significantly
increased the number of mitochondria per unit area in the hippocampus.
This finding helped the researchers to conclude that ketogenic diet
enhances energy production in the hippocampus and may lead to improved
the researchers tested whether brain tissue affected by the ketogenic
diet would be more resistant to low levels of glucose (an effect of
seizures) because of their enhanced energy reserves. They found that
synaptic communication in the ketogenic diet-fed rats was more
resistant to low glucose levels than in rats fed a regular diet.
Dr Raymond Dingledine, pharmacology professor at Emory, said:
findings support our hypothesis that a dietary regimen can dramatically
affect the expression of genes and the function of neurons within the
brain, which enhances the ability of these neurons to withstand the
metabolic challenges of epileptic seizures.
ketogenic diet causes molecules called ketone bodies to be produced as
fat is broken down. Scientists have understood that these molecules
somehow cause a change in metabolism leading to a potent anticonvulsant
effect. According to some animal studies they also may limit the
progression of epilepsy."
researchers believe that as the diet enhances the brain's ability to
withstand metabolic challenges, the ketogenic diet should be studied as
a possible treatment for other neurodegenerative disorders such as
Alzheimer's or Parkinson's diseases.