NADH is an
abbreviation for the reduced form of
nicotinamide adenine dinucleotide.
NADH and NAD (the oxidized
form) are part of what is chemically
known as a redox pair, and are
also considered biologically active
cofactors. These compounds
participate in various oxidation and
reduction reactions throughout the
body. The ubiquitous NADH can reduce
substrates in reactions.
Metabolic
pathways that require NADH include; glycolysis, gluconeogenesis, fatty
acid synthesis and degradation, the
hexose monophosphate pathway, and the tricarboxylic acid pathway. [1] NADH also participates in DNA repair
and maintenance, and cellular
immunity. [2]
Nicotinamide adenine dinucleotide is synthesized from niacin
(also known as vitamin B3),
nicotinamide, and tryptophan.
The pharmacologic and
physiologic effects of NADH
are diverse. NADH has demonstrated
cytokine-modulating effects on
peripheral blood cells. In 18
healthy donors, NADH significantly
stimulated the dose-dependent
release of IL-6, which is an
important cytokine of particular
significance to focal central
nervous system inflammation. [3] This finding is related to treatment
of neurodegenerative diseases like
Alzheimer's and Parkinson's disease.
NADH can be used in the biosynthesis
of tetrahydrobiopterin (BH4),
which is an essential cofactor for
tyrosine hydroxylase, as well. This enzyme is
the rate limiting step in the
production of dopamine. Research in
rat brains has shown that NADH can
increase dopamine release from
striatal slices. [4]
Increased dopamine is important in
the treatment of conditions like
Parkinson's disease.
NADH also has
direct effects on cognitive ability
in animals. One particular study in rats showed
that repeated administrations of NADH
improved the performance of old rats
in the acquisition phase (place
version) and the spatial probe of
the Morris water maze when compared
to vehicle-treated controls. [5]
NADH formation
requires niacin (vitamin B3) and
tryptophan, therefore an adequate
supply of this vitamin and amino
acid is necessary. Good sources of
niacin include unrefined grains,
fortified cereals, milk, and lean
meats (especially liver). Tryptophan
is found in highest levels in brown
rice, cottage cheese, meat, peanuts, and soy proteins. NADH itself must
be taken in supplemental form to
achieve the therapeutic effect.
Currently, research
supports the use of NADH
primarily for three conditions:
chronic fatigue syndrome,
Parkinson's disease, and Alzheimer's
disease.
Chronic fatigue
syndrome (CFS) is a complex disorder
that is diagnosed by criteria
defined by the Centers for Disease
Control. Typically, patients have
prolonged excessive fatigue, and a
myriad of other symptoms such as
muscle pain, headaches and sleep
difficulties. In a study of 35
patients meeting the criteria for CFS, 10 milligrams per day of NADH
or placebo
was administered for 4
weeks. [6] After a 4 week washout period, each
group received the other treatment. The results of the study showed that NADH significantly improved the
symptom score when compared to
placebo. As well, only minor side
effects were noted on the first day
of therapy with NADH.
Another
clinical study was conducted in
patients with CFS to compare the
effectiveness of NADH to standard
conventional therapy. Again, 31
patients meeting CDC criteria for CFS were enrolled in this study. [7]
They were randomized into two
treatment groups: NADH or
nutritional supplements and
psychotherapy for 24 months. The
results showed that for the first
trimester of the study, patients in
the NADH group were significantly
improved compared to those receiving
conventional therapy. However,
following the initial trimester
there were no significant
differences between these groups. The
authors conclude that NADH needs to
be further studied with a larger
sample size to determine
effectiveness in the subsequent
trimesters. Considering that no
therapeutic regimen has proven
effective for treating CFS, NADH
offers a novel approach to treating
this debilitating disorder.
NADH has been
studied in the treatment of
Parkinson's disease. The theory
proposed is that NADH stimulates the
activation of tyrosine hydroxylase,
which in turn may stimulate the
synthesis of endogenous levodopa. Levodopa is typically low in
Parkinson's disease. An initial
clinical trial was conducted in
1989. NADH was administered
either intravenously and
intramuscularly to 34 participants
enrolled in the open study. [8] The results showed that all patients
received benefit from the treatment,
with i.v. application demonstrating
the most clinical benefit. More than
30% improvement in disability was
noted in 62% of the patients. The
best therapeutic dose was observed
between 25 to 50 milligrams per day.
In another clinical trial, patients
with idiopathic Parkinson's disease
were treated with an intravenous
application form of NADH, in addition
to their standard pharmaceutical
therapy, over the course of seven
days. [9] The
results showed that NADH
significantly increased
bioavailability of plasma levodopa
and improved Parkinsonian symptoms. A review of NADH as a treatment for
Parkinson's disease questioned its
application based on the lack of a
supportive large scale
placebo-controlled trials to support
its use. [10]
However, due to the low toxicity
associated with NADH, its
utilization in this condition should not be
discounted.
As mentioned, NADH
has demonstrated positive effects on
the cognitive ability of test animals. Studies have extrapolated this
information and applied it to the
treatment of Alzheimer's. An open
label trial of 17 patients with
dementia of Alzheimer's was
conducted using NADH for 8 - 12
weeks. [11] The results showed improvements in
cognitive ability. Furthermore,
there were no adverse effects noted.
More recently, a double-blind, placebo-controlled study was conducted to
definitively determine if NADH is of
benefit in persons suffering from
Alzheimer's. Twenty six patients with
probable Alzheimer's were randomized
to receive 10 milligrams per day of
stabilized oral NADH or
placebo over a period of 6 months. [12] The results showed that the group
given NADH had no evidence of
progressive concerning cognitive deterioration
and had significantly higher total
scores on the MDRS (Mattis Dementia
Rating Scale) compared with subjects
treated with placebo. This study
confirms that NADH is beneficial to
patients with cognitive decline
caused by Alzheimer's.
Other conditions for
which NADH may be beneficial include
jet lag and age related hypertension
and hypercholesterolemia. [13,
14]
Most studies use a
dose of 10 milligrams daily. An
enteric coated form is the most
effective, avoiding potential breakdown in stomach. Intravenous and
intramuscular forms are also
available. The i.v. form has
demonstrated superior efficacy over
the i.m. form.
|
NADH
Deficiencies and
Toxicities |
NADH Deficiency
NADH deficiency has
not been documented. Applications of NADH appear to be therapeutic only.
NADH Toxicities
NADH is generally
considered a safe therapeutic
substance when taken in recommended
doses. The majority of studies
reveal the absence of severe side
effects in patients taking NADH.
Adverse reactions that
may be observed clinically include;
mild overstimulation, anxiety, loss
of appetite, odd taste, dryness, and
insomnia.
An animal toxicity
study was conducted using a
stabilized, orally absorbable form of NADH
(ENADA). The animals were given dose
levels of 20, 100, and 150 mg/kg for
14 days. Observed effects included a
transitory change in stool formation
with intermediate and high doses, and increases in adrenal,
heart, kidney, liver, brain, and
thyroid weights, primarily in male subjects. However, these effects were not
deemed toxicologically significant. The maximum tolerated
intravenous dose (MTD) of betaNADH
(the reduced form of NADH) was also
determined and was considered to be
500 mg/kg/day. Doses above that
level reduced food consumption and
body weight. [15]
Another animal study involving a
daily dose of 5 mg of ENADA revealed
that this particular form of NADH is
relatively safe. The 5mg dose in a rat
corresponds to a dose of 175 mg per
day in a 70 kilogram human, which is 175
times the recommended daily dosage
of 1 ENADA tablet per day. The
authors conclude that the
recommended dose is generally
regarded as safe. [16]
The following table lists various
products that contain a safe and
reliable source of NADH:
|
Manufacturer |
Ingredient |
Amount |
US RDA |
Learn More |
|
Natrol Extra
Strength |
Enada NADH |
5mg |
-- |
Click Here
 |
|
Source Naturals |
Enada NADH |
2.5 mg |
-- |
Click Here
 |