|Huperzine A: Brain Booster
acetylcholinesterase - please.
It's one of the more unloved substances in the human body, because it
acts as a kind of molecular butcher, cleaving other molecules in half
with grim efficiency. But at least it's highly selective, always
seeking and destroying only the acetylcholine molecule, which it
splits into acetate and choline. Such specificity is characteristic
of all enzymes - proteins that are designed to carry out just one
task, through their catalytic activity.
as most readers probably know, is a versatile neurotransmitter, a
messenger molecule that acts throughout the central and peripheral
nervous systems to mediate a host of vital functions, including many
related to cognition and memory. It is a molecule devoutly to be
desired in ample quantities, not only so we can keep all our marbles,
but so they can stay bright and shiny for the endlessly varied game
GOOD MOLECULES GO BAD, AND VICE VERSA
then, did Mother Nature unleash an enzymatic assassin to keep cutting
the poor acetylcholine molecules in half? Because - and this is
as true of biomolecules as anything else - too much of a good thing
is a bad thing (think glucose and diabetes, e.g.). There must always
be checks and balances and feedback mechanisms to ensure that there
is just enough of what we need, neither too little nor too
much. And so there are "good" molecules that we need for
optimal health, and "bad" molecules (which aren't really
bad, because they serve a necessary purpose) that keep the good ones
from creating havoc through overabundance.
in a chemical analogue to military electronic countermeasures
technology, there is a second tier of "good" molecules that
serve to jam the actions of the bad ones, when necessary, by
inhibiting their ability to perform their assigned functions. One
such is huperzine A, an acetylcholinesterase inhibitor - bad
for acetylcholinesterase and therefore good for acetylcholine. And,
like Chinese boxes, there are yet other molecules that inhibit the
inhibitors . . .
this cats-and-mice game, there is, as always in living organisms, a
delicate balance to be maintained. And, as always, the balance can
get skewed as we age, for some reasons that we understand and many
more that we don't. In any case, if acetylcholinesterase gains the
upper hand and unduly depletes our stores of acetylcholine, really
bad things can happen, such as Alzheimer's disease - not that there
is a clear cause and effect there (few things, including Alzheimer's,
are that simple), but there is a strong correlation that can't be
A (HupA for short), an alkaloid found in the Chinese herb Huperzia
serrata, is effective in improving cognitive and memory abilities
in humans, including those with Alzheimer's disease. In China,
where HupA is used for treating Alzheimer's and myasthenia gravis,
medical scientists have studied its effects on the mental functions
of elderly Alzheimer's patients.1
a rigorously designed and controlled experiment, 60 patients aged 52
to 80 with impaired faculties were treated with synthetic HupA (200
micrograms twice daily) or placebo for 60 days. They were evaluated
with a huge array of both psychological and physiological tests to
determine their mental and physical health before and after the
treatment - and, in particular, to determine whether it made any
difference if the HupA was administered in the form of capsules or
on four of the most important psychological tests, including memory
function, the improvement rates in both groups ranged from 43% to
70%; there was no statistically significant difference between the
capsule group and the tablet group.
researchers also set out to observe the action of HupA on the
damaging effects of oxygen free radicals in the patients' plasma and
erythrocytes (red blood cells). Biochemical tests showed significant
improvement, although not to the reference values for healthy people
in the same age group. The authors speculate that long-term treatment
with HupA might be required to optimize the results.
study also reconfirmed the previously demonstrated safety as well as
efficacy of HupA.2,3
The only side effects noted were mild to moderate nausea and
insomnia, again with no difference between the capsule and tablet
ALSO BENEFIT FROM HUPERZINE
a nutrient that improves mental function in the aged does the same in
the young, that's really interesting. And that is what Chinese
researchers found, in a study designed to determine the efficacy of
HupA on memory and learning in adolescents.4
They selected 34 matched pairs of apparently normal junior middle
school students whose only significant complaints were of poor memory
and difficulty in learning.
pairing was done in terms of age, sex, memory quotient, and overall
psychological health, to ensure that comparisons would be meaningful.
Using these criteria, the researchers found no statistically
significant baseline differences between the students in the two
groups, one of which was to be treated with HupA, the other to
receive a placebo.
a double-blind trial, one member of each pair, chosen randomly, was
given 100 micrograms of synthetic HupA twice daily for four weeks,
while the other member received the placebo. The students' memory
quotients were measured before and after the trial, and their
academic performance in their Chinese, English, and mathematics
lessons was monitored as well.
results: At the end of the study, the HupA group scored significantly
better than the control group on standard memory tests described as
"accumulation," "recognition," "reproduction,"
"association," "tactual [tactile] memory," and
"number of recitation," but not on tests of "picture
memory" or "understanding." They had also done
significantly better in their Chinese and English lessons, but not in
math. No side effects of any kind were noted.
IS PREFERABLE TO PRESCRIPTION DRUGS
A is superior to the drugs tacrine and donepezil, which are
acetylcholinesterase inhibitors widely prescribed for Alzheimer's
disease. There is no question that these drugs are effective, but it
is our view that chemical compounds derived from natural sources are
preferable to those invented by chemists, because the natural ones
are typically safer and freer from unwanted side effects.
SS, Cai ZY, Qu ZW, Yang RM, Cai YL, Wang GQ, Su XQ, Zhong XS, Cheng
RY, Xu WA, Li JX, Feng B. Huperzine-A in capsules and tablets for
treating patients with Alzheimer's disease. Acta Pharmacol Sin
SS, Guo ZX, Wang Z, Du ZM, Xu WA, Yang JS, et al. Efficacy of
tablet huperzine-A on memory, cognition, and behavior in Alzheimer's
disease. Acta Pharmacol Sin 1995;16:391-5.
SS, Xie HB, Du ZM, Tong ZH, Shi QC, Lu KM, et al. Efficacy of tablet
huperzine-A on memory and cognition in patients with benign
senescent forgetfulness. Chin J Clin Pharmacol Ther
QQ, Xu SS, Pan JL, Guo HM, Cao WQ. Huperzine-A capsules enhance
memory and learning performance in 34 pairs of matched adolescent
students. Acta Pharmacol Sin 1999 Jul;20(7):601-3.