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Galantamine
and Other Supplements Help Fight Alzheimer's
Protect
Brain Function by
Enhancing Neurotransmission
by Will Block
Recent evidence from a Canadian study shows that life expectancy in
people suffering from dementia is much shorter than had previously been
believed.1
The study found that the median survival rate for elderly dementia
patients was 3.3 years after the onset of the disease. Previous, less
carefully controlled studies had suggested that the survival rate was
anywhere from 5 to 9.3 years. The clear implication is that dementia
shortens lifespan.
But should we resign ourselves to that fact and
let Mother Nature take her course, doling out the seeds of dementia to
the unlucky among us, while sparing the rest for no apparent reason? No
way! First of all, it's not so much a matter of luck as of lifestyle -
making the right choices. In that sense, we can manufacture our own
"luck," and we are fools if we don't - especially when we
consider that the means are all around us, sometimes even in the flowers
growing at our feet.
Some of those flowers contain galantamine,
a compound that has been found to be as effective in treating
Alzheimer's disease as synthetic drugs. But there are other natural
compounds that are also valuable in this regard, as we will see.
THE
PROGNOSIS FOR ALZHEIMER'S IS POOR
Alzheimer's disease is one of the two dominant types of dementia, which
is defined as a progressive loss of memory accompanied by significant
impairment in other areas of mental function or behavior.*
The slow, inexorable fading away of a once vibrant personality - and
with it, of life itself - is a terrible thing to endure or to witness,
especially in someone we love. As the Canadian study has shown, the
prognosis for patients with dementia is similar to that for patients
with such malignant diseases as cancer and heart disease.2
*The risk
factors for dementia and the protective factors (other than supplements)
against it were discussed in the article, entitled "Preventing
Dementia Can Boost Life Expectancy."
Alzheimer's is a degenerative disease of the brain
tissue itself (in certain parts of the brain). It entails the atrophy or
dysfunction of certain cell groups that underlie the normal neural
mechanisms associated with higher cognitive functions. This is often
accompanied by the development of pathological changes in the brain
called plaques and tangles.
The other dominant type of dementia, vascular
dementia, is caused by cerebrovascular disease, or diseased blood
vessels in the brain. This leads to impaired blood flow and thus
diminished delivery of such vital nutrients as oxygen and glucose to the
brain's cells. It is important to realize that many cases of Alzheimer's
may be complicated by some degree of vascular dementia, simply because
cerebrovascular disease is so common in the elderly.
In this month's article we will look at
Alzheimer's in particular,and how to help prevent it through
supplementation. Next month we will look at vascular dementia, which is,
if anything, even more easily preventable.
HEALTHY
NEUROTRANSMISSION IS VITAL
Whatever it takes to stave off the threat of Alzheimer's is worth doing.
The primary objective is
to enhance neurotransmission so as to retain memory and other
higher cognitive functions. Neurotransmission is the mechanism by
which information travels in the brain - zipping from nerve cell to
nerve cell by jumping across the tiny gaps (called synapses) between
them. This is effected via molecules called neurotransmitters, among the
most important of which is acetylcholine (ACh). One of the
hallmarks of Alzheimer's is a marked reduction of ACh levels in certain
regions of the brain.
There are three approaches to enhancing
neurotransmission by acetylcholine:
1.
Stimulation of ACh production. This is the most direct (but not
necessarily the best) approach. The idea is to boost the brain's
synthesis of ACh by using chemical precursors - compounds whose
reactions with other molecules in the body lead, eventually, to more ACh
molecules.
2.
Protection of existing ACh. This is the approach most widely used
in medical practice, because it has been found to be the most effective.
At all times, the brain's ACh molecules are subject to a natural
regulatory mechanism in which they are attacked and destroyed by an
enzyme called acetylcholinesterase (AChE). Compounds that
suppress AChE are called acetylcholinesterase inhibitors, and
these compounds are the primary agents for treating Alzheimer's disease.
3.
Sensitization of nicotinic receptors. The brain's nerve cells
(neurons) are equipped with different kinds of molecular receptor sites
for the ACh molecules jumping across the synapses. Among the most
important of these are ones called nicotinic receptors, and sensitizing
them to make them more receptive to ACh enhances the efficiency of
neurotransmission.
THE
DOUBLE BENEFIT OF GALANTAMINE
Mother Nature's bounty includes a variety of natural compounds that can
enhance neurotransmission by ACh, and one of them, as mentioned above,
rivals the best synthetic drugs that pharmaceutical companies have to
offer. That compound is galantamine, which has a history of medicinal
use in Europe that goes back many centuries. The flowers from which it
is extracted include snowdrops, daffodils, spider lilies, and a few
others. It takes huge amounts of these flowers to get a little
galantamine, so it cannot be made inexpensively.
Galantamine is a first-rate AChE inhibitor, and,
unlike other AChE inhibitors, it is also a potent sensitizer of
nicotinic receptors, giving it a double whammy against Alzheimer's
disease. Many research studies documenting these attributes have been
published in the international medical literature in recent years. Now a
meta-analysis - a thorough, critical review of the literature - has been
published, with results that confirm the role of galantamine as an
effective treatment for Alzheimer's.3
The authors combed medical journals and
monographs, databases of clinical trials, and directories of Ph.D.
theses for all available information on galantamine's role as a
treatment for Alzheimer's. To ensure that only high-quality research was
included in the meta-analysis, the authors screened the studies for the
following factors: (1) they had to be randomized, double-blind,
placebo-controlled, and unconfounded (i.e., galantamine had to be tested
alone, not in combination with any other agent); (2) they had to have
covered a treatment period of more than 4 weeks for patients with
Alzheimer's disease; and (3) they had to meet additional criteria
regarding the study protocol and the reporting of data. Of the 30
studies examined, seven made the grade.
GALANTAMINE
WORKS AS WELL AS SYNTHETIC DRUGS
From the combined results of these seven studies - all of which involved
patients with mild to moderate Alzheimer's, none severe - the authors
concluded that ".
. . this review shows consistent positive effects for galantamine
in trials of 3 months, 5 months, and 6 months duration. . . .
there is evidence demonstrating efficacy for galantamine on global
ratings, cognitive tests, assessments of ADLs [activities of daily
living], and behavior. The magnitude of the effect on cognition is
similar to other acetylcholinesterase inhibitors, including donepezil,
rivastigmine, and tacrine." (These are the three most widely
used synthetic drugs for treating Alzheimer's disease.)
In other words, in terms of cognitive function
(memory and learning), galantamine works as well as the synthetic drugs.
The dosages most commonly used in these studies were either 24 or 32 mg
per day, but the authors concluded that 16 mg per day is probably
preferable because its efficacy is equal to that of the higher doses,
and it is less likely to cause gastrointestinal upset, a possible side
effect of galantamine. The synthetic drugs can cause GI upset too but
are also notorious for more serious side effects, such as liver toxicity
and heart-rate irregularities.
HUPERZINE
A ALSO WORKS WELL
Another acetylcholinesterase inhibitor with a long history of use - but
primarily in China - is huperzine
A, a compound extracted from the Chinese plant Huperzia
serrata. This compound is effective in improving memory and
cognitive abilities in humans, including those with dementia.*
For example, Chinese scientists studied the
effects of huperzine A (HupA for short) on the mental functions of
elderly Alzheimer's patients.4
Sixty 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 psychological and physiological tests to determine
their mental and physical health before and after the treatment. Based
on four of the most important psychological tests, including memory
function, the improvement rates in both groups ranged from 43% to 70%.
The only side effects of HupA noted in this study were mild to moderate
nausea and insomnia.
OTHER
SUPPLEMENTS CAN HELP TOO
Other natural supplements that may help to enhance neurotransmission
include choline,
which is a chemical precursor of acetylcholine. Some of the choline in
our diet is used by the body to manufacture the ACh it needs (most of
the rest goes into the building of cell walls). Choline works best in
this regard if accompanied by another compound called a cofactor - in
this case, vitamin B5
(pantothenic acid). A larger and more complex version of choline that
also serves as a precursor to ACh is CDP-choline
(also known as citicoline), which has been shown to be effective in
treating Alzheimer's disease.5
Yet another ACh precursor is DMAE
(dimethylaminoethanol), which is similar in molecular structure to
choline. Although DMAE does not appear to improve memory or to be of
benefit in Alzheimer's disease, it may help produce positive behavioral
changes, such as improvements in mood and motivation, in elderly
patients with dementia.6
The herb Ginkgo
biloba has been shown to have beneficial effects in dementias
of the Alzheimer's type and other types as well - probably through
different mechanisms of action.7-9
It is known to improve cognitive function by enhancing neurotransmission
and to improve circulatory function by inhibiting platelet aggregation,
the process that produces blood clots. Both of these functions may be
related to the antioxidant properties of flavonoid compounds in the
ginkgo extract. This is
significant because it is believed that some of the conditions
associated with Alzheimer's disease (as well as with many other aspects
of aging) may be due, in part, to oxidative damage caused by free
radicals.10
Antioxidant properties are the hallmark of two
other agents in this compendium of anti-Alzheimer's supplements: vitamin
C and vitamin E.
These are widely viewed as among the most important antioxidants for
human health in many of its aspects, and this extends to the protection
of brain cells from oxidative damage.
All of these products, alone or in combination,
can help stave off the fog of dementia, which robs you not only of your
marbles but also of life itself. So keep your marbles, and stay sharp
for a long and healthy life. Keep that acetylcholine moving!
References
www.AlzheimersTreatments.com
- Wolfson C, Wolfson DB, Asgharian M, M'Lan CE,
Østbye T, Rockwood K, Hogan DB. A reevaluation of the duration of
survival after the onset of dementia. N Engl J Med 2001 Apr
12;344(15):1111-6.
- Kawas CH, Brookmeyer R. Aging and the public
health effects of dementia. N Engl J Med 2001 Apr
12;344(15):1160-1.
- Olin J, Schneider L. Galantamine for Alzheimer's disease
(Cochrane review). In The Cochrane Library,
Issue 2, 2001. Oxford: Update Software.
- Xu 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 1999 Jun;20(6):486-90.
- Alvarez XA, Mouzo R, Pichel V, Perez P, Laredo
M, Fernandez-Novoa L, Corzo L, Zas R, Alcaraz M, Secades JJ, Lozano
R, Cacabelos R. Double-blind placebo-controlled study with
citicoline in APOE genotyped Alzheimer's disease patients. Effects
on cognitive performance, brain bioelectrical activity, and cerebral
perfusion. Methods Find Exp Clin Pharmacol 1999;21(9):633-44.
- Ferris SH, Sathananthan G, Gershon S, et al.
Senile dementia. Treatment with Deanol. J Am Ger Soc 1977;25:241-4.
- Le Bars PL, Katz MM, Berman N, et al. A
placebo-controlled, double-blind, randomized trial of an extract of Ginkgo
biloba for dementia. North American EGb Study Group. JAMA 1997;278:1327-32.
- Hofferberth B. The efficacy of EGb 761 in
patients with senile dementia of the Alzheimer type, a double-blind,
placebo-controlled study on different levels of investigation. Human
Psychopharmacol 1994;9:215-22.
- Kanowski S, Herrmann W, Stephan K, et al. Proof
of efficacy of the Ginkgo biloba special extract EGb 761 in
outpatients suffering from mild to moderate primary degenerative
dementia of the Alzheimer type or multi-infarct dementia. Pharmacopsychiatry
1996;29:47-56.
- Harman D. Free radical theory of aging: a
hypothesis on pathogenesis of senile dementia of the Alzheimer's
type. Age 1993;16:23-30.
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