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Journal of Aging Research & Clinical Practice©
THE EFFECT OF ELEVATP™ ON WHOLE BLOOD ATP LEVELS:
A SINGLE DOSE, CROSSOVER CLINICAL STUDY
T. Reyes-Izquierdo1, C. Shu1, R. Argumedo1, B. Nemzer2, Z. Pietrzkowski1
Introduction
Adenosine 5’-triphosphate (ATP) is the active source of
energy within cells and participates in numerous
physiological processes. Extracellular ATP and ADP
influence platelet aggregation, vascular tone, and
nervous, cardiac and muscle tissue function (1). ATP is
critical for cell-to-cell communication and participates in
immune cell coordination (2-5). As humans age,
intracellular ATP levels decrease and the ability to
generate ATP is diminished (6-8). Recent evidence also
suggests that aging humans have lower plasma and
erythrocyte-mediated release of ATP, most notably
during periods of increased skeletal muscle blood flow
(9). This may impair vasodilation and oxygen delivery to
the tissues (9).
The clinical effects of oral ATP administration have
been mixed (10, 11). Researchers have failed to
demonstrate that orally administered ATP supplements
increase blood ATP levels (11, 12). This is likely due to
the poor bioavailability of oral ATP (13), since
intravenous administration of ATP has been reported to
increase ATP levels (14). Long term ATP
supplementation may induce intestinal nucleoside
transporters in humans, thereby increasing absorption
(15). However, enteric-coated and distal-releasing ATP
supplements have also failed to increase blood ATP
levels (12). Because of the unpredictable mechanism of
ATP dosing using direct ATP supplementation,
researchers, including our group, are exploring strategies
to increase endogenous ATP levels.
ElevATP™ is an ancient peat-based bioinorganic
material blended with apple extract polyphenols, as
previously described (16). Our pilot study demonstrated
that a single dose of elevATP™ increased whole blood
ATP levels in human subjects without changing reactive
oxygen species, glucose, or lactate levels in the blood (16).
This study extends that work using a crossover design in
a larger group of subjects. We sought to confirm the
results of our pilot study and to evaluate plasma levels of
ATP as well. In addition, biopsy of muscle tissue was
collected from one individual before and after a single
dose of elevATP™ in order to determine intramuscular
ATP levels.
1. Applied BioClinical Inc., 16259 Laguna Canyon Rd, Irvine, CA, USA 92618; 2.
FutureCeuticals Inc., 2692 N. State Rt. 1-17., Momence, IL, USA 60954
Corresponding Author: Tania Reyes-Izquierdo, 16259 Laguna Canyon Rd, Irvine CA,
92618 USA, Phone +1 949 502 4496, Fax +1 949 502 4987, Email:
tania@abclinicaldiscovery.com
1
Abstract: Purpose: elevATP™, a supplement containing plant-derived inorganic microelements and apple polyphenols, was
previously shown to increase endogenous whole blood ATP levels in healthy human subjects. In this report, we tested the
supplement in a larger cohort and assessed the effect of the supplement in muscle. Methods: Twenty healthy, fasted, and resting
adult human subjects participated in this acute, placebo-controlled, single-dose crossover clinical study. Oral placebo was
administered on the first day of testing followed by a single, 150 mg dose of elevATP™ on the second day. Blood was collected
immediately prior to treatment, 60 and 120 minutes after ingestion. Whole blood ATP, plasma ATP, hemoglobin, blood lactate, and
blood glucose levels were collected. A muscle biopsy was performed on one resting study subject before, and 60 and 120 minutes
after, a single dose of elevATP™. Results: elevATP™ increased whole blood levels of ATP by 40% after 60 minutes (p<0.0001) and
by 28% after 120 min (p=0.0009) versus baseline, pre-supplementation levels. ATP plasma levels did not increase after elevATP™
administration under these experimental conditions. Intramuscular ATP levels from biopsy of one patient increased significantly at
60 and 120 minutes after ingestion of elevATP™ and reached higher levels than ATP measured in whole blood. Conclusions: These
results indicate that elevATP™ increases intracellular ATP in blood cells, confirming results from a previous study, and suggest
that it may increase ATP in muscle tissue. Further clinical testing is needed to confirm tissue- and organ-specific changes in ATP
levels following ingestion of elevATP™.
Key words: Blood ATP, plasma ATP, micronutrients, polyphenols.
Received November 15, 2013
Accepted for publication November 20, 2013
REYES-IZQUIERDO_04 LORD_c 04/12/13 08:41 Page1
Materials and Methods
elevATP™ was provided by FutureCeuticals, Inc.,
Momence, IL USA. Dulbecco's phosphate buffered saline
(PBS), phenyl methane-sulfonyl-fluoride (PMSF),
dimethyl sulfoxide (DMSO), leupeptin, EDTA, NaCl,
nitrobenzyl thioinosine (NBTI), KCl, tricine, forskolin,
isobutylmethylxanthine (IBMX) and water were
purchased from Sigma Chem. Co. (St Louis, MO, USA).
ATP stabilizing solution was prepared as described by
Gorman et al. (17) (118 mmol NaCl, 5 mmol KCl, 40 mmol
tricine buffer, 4.15 mmol EDTA, 5 nmol NBTI, 10 µmol
forskolin and 100 µmol IBMX, at pH 7.4 adjusted with 2
mol/L KOH).
Low protein binding microtubes were obtained from
Eppendorf (Hauppauge, NY, USA) and RC DC Protein
Assay Kit II was obtained from Bio-Rad (Palo Alto, CA,
USA). ATP-luciferase assays were obtained from
Calbiochem (San Diego, CA, USA). Heparin capillary
blood collection tubes were obtained from Safe-T-Fill®
(Ram Scientific Inc. Yonkers, NY). A portable gas meter
and CG8+ cartridges were obtained from Abbott
Laboratories (Abbott Park, IL, USA). Total hemoglobin
quantification ELISA kits were obtained from
MyBiosource (San Diego, CA, USA). Accutrend® Lactate
Point of Care and BM-Lactate Strips® were obtained from
Roche (Mannheim, Germany). Accu-Chek® Compact
Plus glucometer and Accu-Chek® test strips were
obtained from Roche Diagnostics (Indianapolis, IN, USA).
Clinical Study
Inclusion and Exclusion Criteria
This clinical case study was conducted according to
guidelines laid out in the Declaration of Helsinki. All
procedures involving human subjects were approved by
the Institutional Review Board at Vita Clinical S.A.
Avenida Circunvalacion Norte #135, Guadalajara, JAL,
Mexico 44 270 (study protocol no. ABC-13-09-ATP).
Twenty subjects were selected to participate. They were
generally healthy, and free of rhinitis, influenza, and
other acute infections. 12 female and 8 male subjects were
selected, with ages ranging from 22 to 35 years and BMI
ranging from 24.1 to 30 kg/m². Exclusion criteria
included diagnosis of diabetes mellitus, allergies to
dietary products, use of anti-inflammatory drugs,
analgesics, statins, diabetic drugs, anti-allergy medicines,
multivitamins, and use of supplements within 15 days of
the start of the study. All participants gave written,
informed consent before any experimental procedure was
performed.
Blood Collection
Enrolled participants were instructed not to eat for 12 h
prior to the initial blood draw. Resting subjects were
given an empty capsule as placebo on Day 1 of the study
and 150 mg of encapsulated elevATP™ on Day 2. 250 mL
of water was administered with the capsules each day.
Two hundred microliters of blood was collected by finger
puncture and placed in Safe-T-Fill® Capillary blood
collection tubes (Ram Scientific Inc. Yonkers, NY). Blood
samples were collected immediately prior to test capsule
administration and at 60 and 120 minutes after ingestion.
Plasma Collection for ATP analysis
One hundred µl of blood was transferred to low-
protein binding tubes (Eppendorf, Hauppauge, NY, USA)
immediately after collection. An equal volume of ATP
stabilizing solution (17) was added to each tube. Tubes
were gently mixed by inversion and centrifuged at 13,000
g for 3 min to pellet cells. Supernatant was transferred to
a clean tube and spun again at 13,000 g for 3 min. The
supernatant was then snap frozen and stored at -80°C
prior to ATP analysis.
ATP Detection and Quantification
Blood ATP or plasma ATP concentration were
determined using ATP Assay Kits (Calbiochem, San
Diego, CA, USA) with a modification to the original
method, as previously described[18]. Briefly, 10 μL of
lysed blood or plasma was loaded onto a white plate
(Corning® Fisher Scientific, Waltham, MA, USA). 100 µL
of ATP nucleotide-releasing buffer containing 1 µL
luciferase enzyme mix was added and the plate
immediately placed on a illuminometer (LMaX,
Molecular Devices; Sunnyvale CA, USA). Readings were
performed for 15 min at 3 min intervals, at 470 nm.
Relative Light Units (RLU) were recorded and ATP
concentrations were determined using a standard ATP
curve.
Hemoglobin Measurement
Hemoglobin levels in plasma were determined using a
double sandwich ELISA (MyBiosource, San Diego, CA,
USA), concentration was determined comparing to a
standard curve, according to the manufacturer’s
instructions. Plasma samples collected with the ATP
stabilizing solution were used for this analysis.
Lactate and Glucose Detection
Blood lactate was measured using an Accutrend®
Lactate Point of Care (Roche, Mannheim, Germany) and
BM-Lactate Strips® (Roche, Mannheim, Germany).
Fifteen µL of blood was loaded onto the strip and lactate
levels were read according to the manufacturer’s
instructions. Glucose was measured using an Accu-
EFFECT OF ELEVATP ON BLOOD ATP LEVELS.
2
REYES-IZQUIERDO_04 LORD_c 04/12/13 08:41 Page2
JOURNAL OF AGING RESEARCH AND CLINICAL PRACTICE©
3
Chek® Compact Plus glucometer (Roche Diagnostics,
Indianapolis, IN, USA) and Accu-Chek® test strips
(Roche Diagnostics, Indianapolis, IN, USA). Glucose was
read according to the manufacturer’s instructions. Lactate
and glucose levels were determined at every collection
time point.
Statistical Analysis
For each result obtained from the described assays,
each subject was normalized to their own value
measured at baseline (T0), before ingestion of elevATP™
or placebo. Levels of each assay at 60 (T60) and 120 (T120)
minutes after treatment were compared within
experimental groups to the baseline and between
experimental groups using a paired t-statistic test.
Descriptive analyses were run in GraphPad® to derive
the mean and standard deviation of each group.
Muscle Biopsy and Surgical Procedure
For the muscle biopsy, one twenty two-year old
healthy subject, with a BMI of 24.5 was recruited,
following the same selection criteria as described for the
clinical crossover study. This clinical case study was
conducted according to guidelines laid out in the
Declaration of Helsinki. This procedure was approved by
the Institutional Review Board at Vita Clinical S.A.
Avenida Circunvalacion Norte #135, Guadalajara, JAL,
Mexico 44 270 (study protocol no. ABC-NCI-13-01-ATP-
Mus1). The study subject was selected from the group of
subjects enrolled for whole blood ATP measurement, as
described above. This subject was fasted and resting
during this experiment. Biopsy was performed using
aseptic technique. An antiseptic solution (Isodine) was
applied to the medial region of the arm, over the right
biceps. An 18 g needle was used to infiltrate the skin with
5 cc lidocaine. A skin incision was made using a 3 mm
skin biopsy punch. Subcutaneous tissue was bluntly
divided, allowing resection of 3 mm2 of biceps muscle
using Metzenbaum scissors. Muscle tissue from the
biceps was collected before, and also 60 and 120 minutes
after, ingestion of elevATP™. Muscle tissue was
deposited in a 50 ml conical tube and frozen using liquid
nitrogen prior to further processing needed for
measuring of ATP.
Measurements of ATP in muscle tissue
Frozen muscle tissue was added to a glass tissue
grinder (Fisher Scientific, Chino, CA, USA) containing
200 μL ice cold ATP stabilizing solution, as previously
described by Gorman et al. (17). Tissue was mechanically
ground and transferred to a low-protein binding
microtube (Eppendorf, Hauppauge, NY, USA). The
sample was centrifuged for 5 min at 10,000 g and
supernatant was used for ATP quantification. ATP
concentration was determined using an ATP Assay Kit
(Calbiochem, San Diego, CA, USA) with a modification to
the original method, as previously described (18).
Hemoglobin levels were also determined in muscle
tissue lysates, using a double sandwich ELISA
(MyBiosource, San Diego, CA, USA), according to the
manufacturer’s instructions. Tissue samples
homogenized in ATP stabilizing solution described by
Gorman et al. (17) were used for this analysis.
Results
Twenty healthy subjects were recruited for this
placebo-controlled, crossover study. Subjects fasted
overnight and were then given an empty capsule as
placebo (Day 1). Blood was collected at baseline (before
treatment) and 60 min (T60) and 120 min (T120) after
treatment. Subjects fasted overnight, prior to Day 2, when
a single capsule containing 150 mg of elevATP™ was
administered to each subject. Blood was obtained as
previously described. Blood ATP and glucose, and
plasma ATP and hemoglobin levels were also
determined.
Figure 1
Effect of elevATP™ on blood ATP levels. elevATP™
significantly increased blood ATP levels by 40% at T60
(p<0.0001) and 28% at T120 (p=0.0009) over initial
baseline T0 values. Data are presented
as Mean +/- SE. n=20
A single dose of 150 mg elevATP significantly
increased blood ATP by 40% at 60 minutes (p<0.0001)
and 28% at 120 min (p=0.0009) as compared to baseline
ATP level at T0 (Figure 1).
Plasma ATP levels were measured using 10 µL of
plasma in a luciferase-based assay. There was no
significant increase in ATP level at T60 (p=0.83) or T120
(p=0.69) in patients treated with elevATP™ (Figure 2).
No change in plasma ATP level was seen after treatment
with placebo.
Hemoglobin levels were determined in all plasma
samples in order to ensure that mechanical disruption of
erythrocytes did not affect plasma ATP levels. The
placebo group had an increase in plasma hemoglobin of
REYES-IZQUIERDO_04 LORD_c 04/12/13 08:41 Page3
34% at T60 and 37% at T120 on day 1, compared to the T0
baseline (Figure 3). On day 2, after treatment with
elevATP™, there was an increase in plasma hemoglobin
level of 4% at T60 and 28% at T120, compared to the new
T0 baseline. There were no statistically significant
differences in placebo and elevATP™ treatments at T60
(p=0.29) and T120 (p=0.76).
Figure 2
Plasma ATP levels after treatment with elevATP™. Data
is presented as Mean +/- SE, Data are presented as %
change over baseline T0. n=20
Blood glucose levels were monitored after treatment
with placebo (Day 1) and after elevATP™ (Day 2), as
previously described. There were no significant
differences in blood glucose levels between treatments at
T60 (p=0.57) or T120 (p=0.59) in the 20 patients examined.
Blood lactate levels remained unchanged after placebo
(Day 1) or elevATP™ (Day 2) administration. The
difference between treatments was not significant either
at T60 (p=0.61) or T120 (p=0.44).
Figure 3
Hemoglobin levels after treatment with elevATP™. There
was a 4% increase at T60 and 28% increase at T120. There
were no statistical differences when compared to placebo.
Data are presented as Mean +/- SE, n=20
Biceps muscle levels of ATP were determined before
and after administration of elevATP™. At T0 (prior to
treatment), 210 pg ATP per mg protein was detected
(Figure 4). ATP level increased in muscle biopsy tissue to
590 pg/mg protein at 60 minutes and 910 pg/mg protein
at 120 minutes. Hemoglobin was also quantified in
muscle biopsy lysates in order to ensure that mechanical
disruption of the tissue did not affect ATP levels (Figure
5). Hemoglobin levels did not increase after treatment.
Figure 4
ATP levels in muscle tissue after treatment with
elevATP™. ATP levels increased significantly after
treatment. Data is presented as mean +/- SE of 4
determinations
Figure 5
Hemoglobin levels in muscle tissue lysates before and
after treatment with elevATP™. Hemoglobin increased
19% over baseline at T60 and 22% at T120. Data is
presented as Mean +/- SD of 3 determinations
Discussion
These findings provide further support for the
assertion that oral administration of elevATP™ increases
whole blood levels of ATP in healthy humans. The
increases reported here are in agreement with our
previous report (16). elevATP™ appears to selectively
and acutely increase ATP levels within the cellular
component of blood. In contrast, ATP levels in cell-free
plasma remained unchanged following elevATP™
ingestion. We verified the integrity of erythrocyte cell
membranes by quantifying hemoglobin concentrations in
plasma. This suggests that ATP did not originate from
ruptured red blood cells. Likewise, we found no changes
in plasma ATP levels after treatment with elevATP™,
suggesting that it is unlikely that elevATP™ affects
extracellular ATP levels.
Red blood cells constitute the largest cellular
4
EFFECT OF ELEVATP ON BLOOD ATP LEVELS.
REYES-IZQUIERDO_04 LORD_c 04/12/13 08:41 Page4
component of blood, comprising approximately 40 to 50%
of the blood volume. Red blood cells are a major carrier of
ATP (19-21), with intracellular concentrations reaching
the millimolar range (17, 22). ATP production in
erythrocytes takes place via glycolysis, rather than within
mitochondria (19). We previously reported that ingestion
of elevATP™ by fasting and resting study subjects did
not alter blood lactate levels, which could be generated
by increased glycolysis and ATP production in red cells
under these experimental conditions (16). These results
suggest that red blood cells did not contribute to
elevation of whole blood ATP level.
Fresh whole blood was collected and immediately
lysed to measure total ATP. This included ATP
originating from all types of cells present in the blood
collected. The lack of changes in blood glucose and lactate
levels suggests that ATP originated from blood cells with
mitochondria, such as platelets and while blood cells.
Platelets, unlike red blood cells, do contain mitochondria.
Platelets contain roughly 40 nmol of ATP and ADP per
mg of platelet protein (23). Platelets can be stimulated
through thrombin activation to achieve low micromolar
concentrations of ATP and ADP (24).
Further support for increased intracellular organ ATP
formation came from our muscle biopsy case study. As
presented here, muscle tissue, which is rich in
mitochondria, exhibited a substantial increase in ATP
levels after elevATP™ ingestion. Additional work in a
larger number of volunteers is in preparation to confirm
the stimulatory effect of elevATP™ on intramuscular
ATP levels in resting subjects. Our previous work
showed that elevATP™ did not increase reactive oxygen
species, despite increasing ATP levels (16). The
relationship between elevATP™ and mitochondrial
Complex IV and/or V activity is currently under
investigation in our laboratory as well as establishing
ATP/phosphocreatine ration before and after ingestion of
elevATP
In conclusion, we have thus confirmed the ability of
elevATP™ to increase ATP levels in whole blood. We
have further shown that elevATP does not increase ATP
levels in plasma. The precise blood cell type or types that
are sensitive to the action of elevATP™ is not known. A
clinical case experiment demonstrated that ingestion of a
single dose of elevATP™ resulted in a significant increase
in intramuscular ATP under resting conditions. This
result suggests that ingestion of elevATP™ may increase
ATP level in other tissues. Further clinical testing is
justified and is needed to confirm this preliminary result.
Investigating whether elevATP™ may improve muscle
performance and endurance in young and aged
individuals and such experimentation is also justified and
is currently in preparation.
Acknowledgments: All authors declare that they have no conflicts of interest.
The present study was funded by Futureceuticals, Inc. We express our gratitude to
John Hunter and Brad Evers (FutureCeuticals, Inc.) for their comments and
suggestions in the preparation of this article. We would like to thank Michael
Sapko for his help in editing the manuscript.
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