The Glial Cell and
Incipient Dementia
Short Circuiting the Brain.
The human brain has never before
been presented with chronic excess
energy in the circulation – its evolutionary history is one of exposure to food and energy famine.
The brain is highly efficient at preserving its energy supply during
energy famines or starvation (as
in anorexia nervosa), but has not
evolved sophisticated mechanisms
to deal with chronic systemic energy excess – it simply suppresses
energy income and triggers a protracted short circuit (chronic/not
acute).
The key to understanding a range
of modern metabolic diseases, both
physiological and neurological, is to
be found in the glial cell. That is to
say that this cell, for which there
are around 6 for every neurone, is
ground zero in obesity/diabetes/
cardiovascular disease and a variety of neurological conditions such
as Alzheimer’s disease/motor neurone disease/Parkinson’s disease
and multiple sclerosis.
The human brain affords the highest rate of energy consumption
known in nature. Indeed on a like
for like basis the human brain consumes 22 times the energy of a
muscle cell (The Expensive Tissue
Hypothesis). At any moment there
is only around 1 gram of glucose
in the brain – sufficient for only a
few minutes. The circulation carries only 5 grams so a fall in blood
glucose concentration (hypoglycaemia) is catastrophic for the brain
and will rapidly lead to a coma, if
not reversed.
The cerebral glucose pump – the glutamate/glu30