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Zynamite® ( Mangifera indica Leaf Extract) and Caffeine Act in a Synergistic Manner on Electrophysiological Parameters of Rat Central Nervous System

Authors:
  • Mewicon Cateem-tec Neureichenau, Germany
  • Dr. Gericke Consulting

Abstract and Figures

Zynamite®, a special extract from Mangifera indica, exerted stimulatory properties on the central nervous system during a pilot study. The question arose if Zynamite® would have a similar action on the central nervous system as caffeine. Two well established animal models were used: a) quantitation of spectral power of field potentials in the freely moving rat and b) induction of long term potentiation (LTP) in the hippocampus slice preparation ex vivo after one week of daily administration. In the presence of 25 mg/kg of Zynamite®, predominantly alpha2 and beta1 spectral frequencies were attenuated in all brain areas during the first hour after administration. Exactly this pattern of frequency changes had been observed in earlier studies with i.p. administration of caffeine. Discriminant analysis confirmed this similarity by projection of Zynamite® and 0.5 mg/kg caffeine into close neighborhood and showing identical colours, which points to a similar mechanism of action in this analysis. In addition, when Zynamite® was combined with very low doses of caffeine synergistic effects were observed. Since alpha2 waves are under the control of dopamine, activation of this neurotransmitter system might be responsible for the stimulating property of Zynamite®. These results are corroborated by the results from the ex vivo study using the hippocampus slice in vitro to follow changes in excitability in the presence of 0.5 mg/kg of caffeine, 25 mg/kg of Zynamite® or their combination in comparison to Placebo after daily administration for one week. Both caffeine and Zynamite® increased LTP. LTP relates to space and time dependent memory. From these studies it is evident that both caffeine and Zynamite® act in similar ways on brain electrical activity, and have potential to improve cognitive function. Bioactive compounds of Zynamite® clearly pass the blood brain barrier to act on the central nervous system. Due to the demonstrated similarity of action, Zynamite® has potential as a CNS-activating nutraceutical that could be used to replace caffeine.
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Food and Nutrition Sciences, 2018, 9, 502-518
http://www.scirp.org/journal/fns
ISSN Online: 2157-9458
ISSN Print: 2157-944X
DOI:
10.4236/fns.2018.95039 May 22, 2018 502 Food and Nutrition
Sciences
Zynamite® (Mangifera indica Leaf Extract) and
Caffeine Act in a Synergistic Manner on
Electrophysiological Parameters of Rat Central
Nervous System
Wilfried Dimpfel1*, Julia Wiebe2, Nigel Gericke2, Leonie Schombert3
1Justus-Liebig-University Giessen c/o NeuroCode AG, Wetzlar, Germany
2Nektium S.L., Las Palmas, Spain
3NeuroCode AG, Wetzlar, Germany
Abstract
Zynamite®, a special extract from
Mangifera indica
, exerted stimulatory pro
p-
erties on the central nervous system during a pilot study. The question arose
if
Zynamite® would have a similar action on the central nervous system
as
caffeine. Two well established animal models were used: a) quantitation
of
spectral power of field potentials in the freely moving rat and b) induction
of
long term potentiation (LTP) in the hippocampus slice preparation ex
vivo
after one week of daily administration. In the presence of 25 mg/kg of Zyn
a-
mite®, predominantly alpha2 and beta1 spectral frequencies were
attenuated
in all brain areas during the first hour after administration. Exactly this pa
t-
tern of frequency changes had been observed in earlier studies with i.p. a
d-
ministration of caffeine. Discriminant analysis confirmed this similarity
by
projection of Zynamite® and 0.5 mg/kg caffeine into close neighborhood
and
showing identical colours, which points to a similar mechanism of action
in
this analysis. In addition, when Zynamite® was combined with very low
doses
of caffeine synergistic effects were observed. Since alpha2 waves are under
the
control of dopamine, activation of this neurotransmitter system might be r
e-
sponsible for the stimulating property of Zynamite®. These results are corr
o-
borated by the results from the ex vivo study using the hippocampus slice
in
vitro to follow changes in excitability in the presence of 0.5 mg/kg of
caffeine,
25 mg/kg of Zynamit or their combination in comparison to Placebo
after
daily administration for one week. Both caffeine and Zynamite®
increased
LTP. LTP relates to space and time dependent memory. From these studies
it
is evident that both caffeine and Zynamite® act in similar ways on brain elec-
How to cite this paper:
Dimpfel, W.,
Wiebe
, J., Gericke, N. and Schombert, L.
(201
8)
Zynamite® (Mangifera indica Leaf
Extract) and Caffeine Act in a Synergistic
Manner on Electrophysiological Param
e-
ters of Rat Central Nervous System
.
Food
and
Nutrition Sciences
,
9
, 502-518.
https://doi.org/10.4236/fns.2018.95039
Received:
April 5, 2018
Accepted:
May 19, 2018
Published:
May 22, 2018
Copyright
© 2018 by authors and
Scientific
Research Publishing Inc.
This
work is licensed under the Creative
Commons
Attribution International
License
(CC BY 4.0).
http://creativecommons.org/licenses/by/4.0/
Open Access
W. Dimpfel et al.
DOI:
10.4236/fns.2018.95039 503 Food and Nutrition
Sciences
trical activity, and have potential to improve cognitive function. Bioactive
compounds of Zynamite® clearly pass the blood brain barrier to act on
the
central nervous system. Due to the demonstrated similarity of action, Zyn
a-
mite® has potential as a CNS-activating nutraceutical that could be used to r
e-
place caffeine.
Keywords
Zynamite®,
Mangifera indica
, Caffeine, Rat, Field Potential, Hippocampus
Slice, Synergy
1. Introduction
Mangifera indica
is commonly known as “Mango” and belongs to the family of
Anacardiaceae. It was domesticated in India about 2000 BC (Wikipedia). The
leaves contain a high amount of Mangiferin, a pharmacologically active hydrox-
ylated xanthone C-glycoside. Extract of the leaves have shown antibiotic proper-
ties and have diverse uses in traditional Ayurveda medicine [1].
This investigation deals with Zynamite®, a special Mango leaf extract contain-
ing 60% of Mangiferin. Since a recent pilot clinical trial in 16 healthy subjects
has shown brain stimulatory activity with no cardiovascular changes, the ques-
tion arose whether Zynamite® could replace caffeine without the side effects
known for intake of high doses of caffeine. The present series of experiments
focus on the comparison of the effect of Zynamite®, caffeine and a combination
thereof to placebo 1) with respect to quantitation of spectral power of field po-
tentials in the freely moving rat and 2) with respect to induction of long term
potentiation in the hippocampus slice preparation
ex vivo
after one week of daily
administration.
Recording of field potentials from freely moving rats and their wireless trans-
mission has been used now for more than 30 years [2]. Frequency analysis of
signals from four brain regions (frontal cortex, hippocampus, striatum and reti-
cular formation) by Fast Fourier transformation (FFT) allowed to differentiate
clinically used drugs with respect to their indication when using linear discrimi-
nant analysis [3]. This method has been demonstrated to be able to characterize
CNS-active herbal preparations with respect to their potential clinical use [4].
The hippocampal slice preparation is a validated model for direct analysis of
interaction of substances with living neuronal tissue [5] [6]. Due to the preserva-
tion of the three-dimensional structure of the hippocampal tissue, substance ef-
fects on the excitability of pyramidal cells can be studied in a unique manner.
The stimulation of Schaffer Collaterals leads to release of glutamate resulting in
excitation of the postsynaptic pyramidal cells. The result of the electrical stimu-
lation is recorded as so-called population spike (pop-spike) representing the
number of recruited pyramidal cells. An interesting result using this model was
for example the demonstration of the ability of memantine, a pharmaceutical
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used in the treatment of dementia, to increase the population spike amplitude in
response to single stimuli and theta burst stimulation to increase long term po-
tentiation [7].
2. Material and Methods
2.1. Field Potential Analysis in Freely Moving Rats
EEG signals were recorded from frontal cortex, hippocampus, striatum and re-
ticular formation of freely moving rats from inside a totally copper shielded
room. Signals were wirelessly transmitted by a radio-telemetric system (Rhema
Labortechnik, Hofheim, Germany, using 40 Megahertz as carrier frequency) and
were amplified and processed as described earlier to give power spectra with a
resolution of 0.25 Hz [8]. In short, after automatic artefact rejection signals were
collected in sweeps of 4 s duration and Fast Fourier transformed using a Han-
ning window. Sampling frequency was 512 Hz. Four values were averaged to
give a final sampling frequency of 128 Hz, well above the Nyquist frequency. The
resulting electrical power spectra were divided into 8 specially defined frequency
ranges (delta: 1.50 - 4.00 Hz; theta: 4.25 - 6.75 Hz; alpha1: 7.00 - 9.50 Hz; alpha2:
9.75 - 12.25 Hz; beta1a: 12.50 - 15.00 Hz; beta1b: 15.25 - 17.75 Hz; beta2: 18.00 -
34.25 Hz; gamma: 34.50 - 81.00 Hz). Spectra were averaged in steps of 3 minutes
each and displayed on-line. In an off-line procedure spectra were averaged to
give longer periods for further analysis and data presentation. All dosages of
caffeine and its combination with Zynamite® were tested by oral acute adminis-
tration. Dosage of Zynamite was chosen on the base of earlier experiments. Solu-
tions were prepared fresh for each experimental day and administered orally by
gavage after 45 minutes of pre-drug Vehicle recording. Vehicle was water. Ex-
tracts are listed in Table 1.
Nine adult male Fisher 344 rats (5 months of age and day-night converted,
weight about 350 - 400 g, provided by Charles River Laboratories, D-97633,
Sulzfeld) remained from a preceding study with allowance from the local legal
authority “Regierungspräsidum Giessen” and were used in this experimental se-
ries. Animals were day-night reversed (12h/12h). The principles of good labora-
tory animal care were followed in all trials. Animals were implanted with
Table 1. Test drugs-Listing of experimental extracts and vehicle.
Test drugs
Dose
From
Zynamite®
25 mg/kg
Nektium Pharma S.L.
Zynamite® + Caffeine
EP USP Natural Anhydrous
25 mg/kg + 0.25 mg/kg
Nektium Pharma S.L.
Zynamite® + Caffeine
EP USP Natural Anhydrous
25 mg/kg + 0.50 mg/kg
Nektium Pharma S.L.
Caffeine EP USP Natural Anhydrous
0.5 mg/kg
Nektium Pharma S.L.
VEHICLE 0.9% NaCl
1.0 ml/kg
Braun Melsungen
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electrodes into the brain and were given two weeks for recovery from surgery.
After this, the wireless transmitter was plugged in for adaptation and control
experiments. Unfortunately, 3 animals dropped the implant after performance of
the placebo series. After testing the two combinations one further animal
dropped the implant thus allowing to test the final single dose of caffeine in only
5 animals. During the recording rats were not restricted and could move freely
but did not have food available (chewing would have produced too many arte-
facts).
Rats were implanted as reported earlier [8]. A crossover design with at least
three days of drug holidays in between the administrations was used. Controls
were performed by oral administration of 1.0 ml/kg of vehicle (0.9% NaCl) and
the mixture Zynamite® (25 mg/kg) and Caffeine (0.25 and 0.50 mg/kg) as well as
Caffeine (0.50 mg/kg). Data were averaged from 5 - 9 animals. Data are ex-
pressed as mean values ± S.E.M. Statistics were calculated by means of the Wil-
coxon, Mann, Whitney U-test. The animals were dosed orally at a constant vo-
lume of 1.0 ml/kg per kg body weight. The dosage administered to each animal
was determined every day by the weight of that animal at the time of administra-
tion. Wilcoxon, Mann, Whitney U-test was used throughout all experimental
data for comparison to results obtained by vehicle administration at the particu-
lar timing.
2.2. Ex Vivo Analysis of Population Spikes in the Hippocampal
Slice Preparation
Hippocampus slices were prepared as reported earlier [8]. In short, after daily
administration of trial medication for one week 4 animals were sacrificed under
deep anesthesia and the hippocampus was quickly taken out and chopped by a
vibrating razor blade to give 6 slices of about 400 µ thickness per animal. After
adaptation to artificial cerebrospinal fluid for one hour, slices were transferred to
an incubation chamber [9] and superfused with cerebrospinal fluid at 35˚C [10].
Stimulation of the Schaffer Collaterals by single stimuli or theta burst stimuli
resulted in the induction of a population spike or long-term potentiation, re-
spectively [5]. Amplitudes of the population spikes were recorded after stimula-
tion every 10 minutes to prevent potentiation mechanisms. Each animal had
been treated for one week with each one of the preparations. Slices were taken
one day after the last treatment. Excitability of the hippocampus slices was
checked after administration of 25 mg/kg of Zynamite®, a combination with 0.5
mg/kg of caffeine and 0.5 mg/kg of caffeine alone. Rats were treated with each of
the preparations daily for one week before the hippocampus was taken out at the
next day. An example of the amplitude of the population spike after single shock
stimulation and theta burst stimulation is given in Figure 1 for the animal
treated with placebo (upper part of the image) and the combination of Zyna-
mite® with caffeine (lower part of the image). Stimulation of the Schaffer Colla-
terals was performed only every 10 minutes in order to prevent physiological
potentiation mechanisms.
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Figure 1. Documentation of original signals (one slice) showing the effects of
using single stimuli (SS) or theta burst stimulation (TBS) in the presence of ar-
tificial cerebro-spinal fluid (ASCF), Placebo 1 ml/kg or combination from Zy-
namite® (25 mg/kg) and Caffeine (0.5 mg/kg). The amplitude is calculated
from baseline to the down reflection of the signal (shadowed). Scales: Time is
given in milliseconds (ms), amplitude in millivolts (mV).
3. Results
3.1. Field Potential Analysis
Oral administration of the vehicle (0.9% NaCl) only resulted in very minor
changes of spectral power within the four brain areas. During the second and
third to the fifth hour tiny decreases of power emerged in the frontal cortex and
hippocampus. With respect to gamma power some tiny increases were observed.
A complete time course is given in Figure 2.
Oral administration of 25 mg/kg of Zynamite® resulted in a statistically signif-
icant attenuation of all classic frequencies during the first hour after administra-
tion. Strongest effects were documented with respect to alpha2 and beta1 spec-
tral frequencies. Mainly frontal cortex and striatum were involved. During the
third hour after administration significant increases of delta power were seen (p
< 0.05). Within the striatum a non-significant attenuation of alpha1 and beta
power was recognized throughout the whole recording period of 5 hours (Figure
3).
Oral administration of Caffeine (0.50 mg/kg) resulted in a statistically con-
spicuous attenuation (p < 0.1) of delta power in the frontal cortex. In the hippo-
campus statistically significant attenuation of delta, theta and beta power was
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Figure 2. Effect of Vehicle: Time dependence of changes of spectral power (Ordinate)
in % of the 45 min lasting pre-drug baseline values in four brain regions of the freely
moving rat in the presence of Vehicle (0.9% NaCl 1.0 ml/kg). Frequency ranges are de-
picted as coloured bar graphs on the abscissa representing delta (red), theta (orange), al-
pha1 (yellow), alpha2 (green), beta1a (light blue) and beta1b (dark blue) and gamma
spectral power (violet) from left to right within the four brain areas as mentioned on top
of the graph.
Figure 3. Frequency changes in the presence of 25 mg/kg Zynamite®. Frequency ranges
are depicted as coloured bar graphs on the abscissa representing delta (red), theta
(orange), alpha1 (yellow), alpha2 (green), beta1a (light blue) and beta1b (dark blue) and
gamma spectral power (violet) from left to right within the four brain areas as mentioned
on top of the graph. Statistical significance in comparison to control (vehicle) is docu-
mented by stars: * = p < 0.10; ** = p < 0.05; *** = p < 0.01.
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recognized. In the striatum a minor but statistically conspicuous decrease of
delta waves was seen. From the second hour after administration on, increases of
delta power emerged for the rest of the recording period in the frontal cortex
and reticular formation. During the last hour increases of alpha2 power were
observed except for the striatum. A whole time course is given in Figure 4.
Oral administration of the combination of Zynamite® (25 mg/kg) + Caffeine
(0.25 mg/kg) resulted in a statistically significant attenuation of all frequencies
except for delta spectral power in comparison to placebo during the first hour
after administration. Strongest attenuation was seen with respect to alpha1 and
beta1 power in all brain regions. The alpha1 attenuation lasted into the second
hour after administration, within the striatum into the last hour. During the
third hour an increase of delta power emerged in the frontal cortex and hippo-
campus and somewhat less in the reticular formation. At the same time signifi-
cant increases of alpha2 power were documented during the last 2 hours after
administration. A total time course is given in Figure 5.
Oral administration of the mixture of Zynamite® (25 mg/kg) with Caffeine
(0.50 mg/kg) resulted in a statistically significant attenuation of spectral power
with respect to all frequencies except for gamma power in comparison to place-
bo during the first two hours after administration. Effects were strongest in
frontal cortex and hippocampus. The attenuation lasted until the third hour after
administration, in the hippocampus and striatum until the end of the recording
period. A total time course is given in Figure 6. When directly comparing the
Figure 4. Frequency changes in the presence of 0.5 mg/kg caffeine. Frequency ranges are
depicted as coloured bar graphs on the abscissa representing delta (red), theta (orange),
alpha1 (yellow), alpha2 (green), beta1a (light blue) and beta1b (dark blue) and gamma
spectral power (violet) from left to right within the four brain areas as mentioned on top
of the graph. Statistical significance in comparison to control (vehicle) is documented by
stars: * = p < 0.10; ** = p < 0.05; *** = p < 0.01.
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Figure 5. Frequency changes in the presence Zynamite® (25 mg/kg) in combination with
0.25 mg/kg caffeine. Frequency ranges are depicted as coloured bar graphs on the abscissa
representing delta (red), theta (orange), alpha1 (yellow), alpha2 (green), beta1a (light
blue) and beta1b (dark blue) and gamma spectral power (violet) from left to right within
the four brain areas as mentioned on top of the graph. Statistical significance in compari-
son to control (vehicle) is documented by stars: * = p < 0.10; ** = p < 0.05; *** = p < 0.01.
Figure 6. Frequency changes in the presence of Zynamit (25 mg/kg) in combination
with 0.5 mg/kg caffeine. Frequency ranges are depicted as coloured bar graphs on the ab-
scissa representing delta (red), theta (orange), alpha1 (yellow), alpha2 (green), beta1a (light
blue) and beta1b (dark blue) and gamma spectral power (violet) from left to right within
the four brain areas as mentioned on top of the graph. Statistical significance in compari-
son to control (vehicle) is documented by stars: * = p < 0.10; ** = p < 0.05; *** = p < 0.01.
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effects of Zynamite® and caffeine during the first hour after administration a
close similarity between both becomes visible. Both combinations induce a much
stronger attenuation of nearly all frequencies. Strongest difference to the
mono-preparation consists in a large decrease of alpha1 spectral frequencies in-
dicating a different mechanism of action (Figure 7). This alpha1 attenuation al-
so dominates the effect of Zynamite® and caffeine during the second hour after
administration. Likewise, the combination of Zynamite® with the low dose of
caffeine shows a strong attenuation with respect to alpha1 waves (Figure 8). A
massive attenuation of all frequencies is observed in the presence of the combi-
nation of Zynamite® (25 mg/kg) with the higher dose of caffeine (0.5 mg/kg).
This indicates a synergistic action, which can be demonstrated even more clearly
when looking at the frequency changes in the hippocampus during the first 2
hours after administration (Figure 9).
A valuable methodology for comparison of frequency changes induced by dif-
ferent preparations has been described in numerous publications. Feeding all 24
variables (4 brain areas times 6 frequency ranges) into linear discriminant analy-
sis the similarity of the action of Zynamite® and a low dose of caffeine is con-
firmed by projection of both in close neighborhood and showing the identical
blue colour (Figure 10). The result of the combination is shifted more towards
the plots for Paullinia and Methylphenidate indicating a different mechanism of
Figure 7. Direct comparison of the frequency changes observed in the presence of Zyna-
mite® and caffeine alone and in the presence of the combinations during the first hour
after administration. Frequency ranges are depicted as coloured bar graphs on the abscis-
sa representing delta (red), theta (orange), alpha1 (yellow), alpha2 (green), beta1a (light
blue) and beta1b (dark blue) and gamma spectral power (violet) from left to right within
the four brain areas as mentioned on top of the graph. Statistical significance in compari-
son to control (vehicle) is documented by stars: * = p < 0.10; ** = p < 0.05; *** = p < 0.01.
Please note different scaling with respect to ordinate in comparison to previous images.
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Figure 8. Direct comparison of the frequency changes observed in the presence of Zyna-
mite® and caffeine alone and in the presence of the combinations during the second
hour after administration. Frequency ranges are depicted as coloured bar graphs on the
abscissa representing delta (red), theta (orange), alpha1 (yellow), alpha2 (green), beta1a
(light blue) and beta1b (dark blue) and gamma spectral power (violet) from left to right
within the four brain areas as mentioned on top of the graph. Statistical significance in
comparison to control (vehicle) is documented by stars: * = p < 0.10; ** = p < 0.05; *** =
p < 0.01. Please note different scaling with respect to ordinate in comparison to previous
images.
Figure 9. Documentation of synergy with respect to Caffeine and Zynamite® alone and
their combination during the first two hours after administration in the hippocampus.
Frequency ranges are depicted as coloured bar graphs on the abscissa representing delta
(red), theta (orange), alpha1 (yellow), alpha2 (green), beta1a (light blue) and beta1b (dark
blue) and gamma spectral power (violet) from left to right within the four brain areas as
mentioned on top of the graph. Statistical significance in comparison to control (vehicle)
is documented by stars: * = p < 0.10; ** = p < 0.05; *** = p < 0.01. Please note different
scaling with respect to ordinate in comparison to previous images.
action for the combination than for the mono-preparations. Details of adminis-
tration of the preparation are listed in Table 2.
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Figure 10. Documentation of the result of linear discriminant analysis of field potential
data. Results of the first three discriminant functions are projected using spatial x, y and
z-axis. Results from the next three functions are coded in colour using additive colour
mixture according RGB like in TV.
Table 2. Listing of reference compounds documented in the discriminant analysis with
respect to dosage and the type of administration. “i.p.” = intraperitoneal administration.
Dose
[mg/kg]
Application
Time
Substance
Analysis
Dose
[mg/kg]
Application
Time
Diazepam 0.50 i.p. 5 - 35 min Ginkgo 100.00 orally 5 - 65
min
Memantine 3.00 i.p. 5 - 35 min Paullinia 15.00 orally 5 - 35
min
L-Polamidon 1.00 i.p. 5 - 35 min Valeriana 60.00 orally 125 - 185
min
Ziprasidone 1.00 i.p. 5 - 35 min Humulus 50.00 orally 125 - 185
min
Paroxetine 1.00 i.p. 5 - 35 min
(+)
Amphetamine 0.20 i.p. 5 - 35 min
Propofol 60.00 i.p. 5 - 65 min Zynamite 25.00 orally 5 - 65
min
Moclobemide 5.00 i.p. 5 - 35 min Zynamite +
Caffeine
25.00
+ 0.25 orally 5 - 65
min
Tramadol 5.00 i.p. 5 - 35 min
Methylpenidate 2.50 orally 5 - 35 min
Haloperidol 0.50 i.p. 5 - 35 min
Caffeine 0.50 orally 5 - 65 min
Phenytoin 4.00 i.p. 65 -
125 min
Sleep 65 -
125 min
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Analysis of motion only revealed a statistically significant transient increase in
the presence of the combination of Zynamite® with the lower dose of caffeine
during the first hour. Caffeine alone and the combination of Zynamite® with the
higher dose of caffeine induced higher motion during the first hour after admin-
istration, but did not reach statistical significance (Table 3).
3.2. Ex Vivo Analysis by Means of Hippocampus Slice Preparation
Time courses of the recordings from the 4 animals revealed very stable results
over 2 hours. Population spike amplitudes after administration of 0.5 mg/kg of
caffeine revealed no difference to placebo during single shock stimulation (blue
line in Figure 11), but revealed clearly higher amplitudes during theta burst
stimulation (green line in Figure 11).
The daily administration of 25 mg/kg of Zynamite® resulted in definitely
higher amplitudes of the population spike already during single shock stimula-
tion as documented in Figure 11. Theta burst stimulation induced not only
massive higher amplitudes than after Placebo administration, but also clearly
higher amplitudes in comparison to administration of caffeine (red line in Fig-
ure 11).
Finally, recording of population spike amplitudes after daily administration of
the combination of 25 mg/kg Zynamite® with 0.5 mg/kg of caffeine revealed
highest values during single shock stimulation as well during theta burst stimu-
lation (dark blue line in Figure 11). The mean average values of three measure-
ments (shadowed area in Figure 11) are documented with statistical signific-
ances in Figure 12.
Regarding now the numerical differences of the population spike amplitudes
during single shock stimulation an over-additive effect becomes visible when
comparing the effect of caffeine and Zynamite® alone with the combination.
With respect to theta burst stimulation at least an additive effect is obvious
(Table 4).
Table 3. Results of motion analysis.
Motion [cm|h]
Time
[min]
Vehicle
0.9% NaCl
1 ml/kg
n = 9
Caffeine
0.50 mg/kg
n = 5
Zynamite 25.0 mg/kg
+ Caffeine 0.25 mg/kg
n = 6
Zynamite 25.0 mg/kg
+ Caffeine 0.50 mg/kg
n = 6
45 - 0
626.67 ± 120 874.45 ± 299 854.52 ± 142 650.78 ± 235
5 - 65
676.49 ± 117 1049.00 ± 112 1170.00 ± 160 P = 0.05 1060.00 ± 239
65 - 125
794.39 ± 97 798.41 ± 83 952.00 ± 240 994.55 ± 218
125 - 185
1051.10 ± 81 682.94 ± 143 677.73 ± 128
1040.00 ± 205
185 - 245
913.30 ± 89 843.34 ± 154 603.47 ± 154 847.19 ± 198
245 - 305
695.38 ± 80 629.49 ± 115 696.78 ± 98 870.84 ± 224
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Figure 11. Time dependent effects of Control (Placebo), Caffeine (0.5 mg/kg), Zynamite®
(25.0 mg/kg), and a combination of both (Zynamite® 25.0 mg/kg + Caffeine 0.5 mg/kg)
on pyramidal cell activity in terms of changes of population spike amplitudes (as voltage
on the ordinate). Results as obtained after performance of single stimuli (10 - 80 min) or
after burst stimuli (90 - 120 min). Data are given as mean ± S.E.M. of n = 6 slices from 1
animal. Values from shadowed areas are averaged to give one value as documented in
Figure 12.
Figure 12. Effects of Control (Placebo), Caffeine (0.5 mg/kg), Zynamite® (25.0 mg/kg)
and a combination of both (Zynamite® 25.0 mg/kg + Caffeine 0.5 mg/kg) on pyramidal
cell activity in terms of changes of population spike amplitudes (as voltage on the ordi-
nate). Results as obtained after performance of single stimuli (60 - 80 min) or after burst
stimuli (90 - 120 min). Data are given as mean ± S.E.M. of n = 6 slices from 1 animal.
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Table 4. Documentation of mean numeric differences between the 4 preparations in the
presence of single stimuli and theta burst stimuli. Please note over-additive effect during
single stimuli.
Mean ± SEM
[µV]
SS
60 - 80 min
Diff.
[µV]
TBS
100 - 120 min
Diff.
[µV]
Control
1226.48 ± 23.85
2691.17 ± 39.78
Caffeine 0.5 mg/kg
1289.17 ± 27.43
62.69
3101.22 ± 100.84
410.05
Zynamite 25.0 mg/kg
1571.89 ± 24.46
345.41
3401.67 ± 57.47
710.50
Zynamite 25.0 mg/kg
+ Caffeine 0.5 mg/kg
1733.72 ± 46.30
507.24
3762.39 ± 67.25
1071.22
4. Discussion
The animal model “Tele-Stereo-EEG” [2] has been used to characterize more
than 200 preparations with respect to changes of the frequency content of field
potentials recorded from different regions of the depth of the brain, namely
frontal cortex, hippocampus, striatum and reticular formation. Feeding the data
into linear discriminant analysis revealed that classical CNS-active drugs with
well-established clinical indications group together according to the categories of
clinical application [3].
The result of the present investigation revealed that the administration of Zy-
namite® or caffeine alone induced statistically significant attenuation of spectral
power during the first hour after administration. In the presence of Zynamite®
predominantly alpha2 and beta1 spectral frequencies in all brain areas were at-
tenuated. Exactly this pattern of frequency changes with respect to dominating
attenuation of alpha2 and beta1 frequencies was observed after intraperitoneal
injection of higher dosages of 1 mg/kg, 2.5 mg/kg or 5 mg/kg of caffeine [11].
Thus, there is a great similarity between the frequency changes induced by Zy-
namite® with those seen in the presence of caffeine. Further, discriminant analy-
sis confirms this similarity by projection the results of both preparations in close
proximity to each other and showing identical colours, which points to a similar
stimulant category of CNS activity.
Since it has been shown, that alpha2 waves are predominantly under the con-
trol of dopamine, activation of this neurotransmitter system might be responsi-
ble for the stimulating property of Zynamite®. Beta1 waves seem to be regulated
by the neurotransmitter glutamate [12]. Changes of the glutamatergic system are
observed during performance of cognitive tasks. Interestingly, Mangiferin, the
major bioactive ingredient in Zynamite® has been reported to improve long-term
object memory in rats [13]. Bioavailability of Mangiferin has been shown to be
increased after oral administration of a polyherbal preparation in comparison to
administration of isolated pure Mangiferin, and that Mangiferin was bound to
various tissues except for the brain [14]. This raises the question if Mangiferin
alone is responsible for the activating effect of Zynamite® or if co-ingredients
W. Dimpfel et al.
DOI:
10.4236/fns.2018.95039 516 Food and Nutrition
Sciences
from the remaining 40% of the herbal formulation also contain pharmacologi-
cally active principles. The reproducible and stable attenuation of alpha1 spectral
power during the rest of the recording time is interpreted as a higher state of
wakefulness. Alpha1 waves are under the control of serotonin as reported earlier
[15].
However, when Zynamite® was combined with very low doses of caffeine
more than mere additive effects were observed. This can be recognized best by
focusing on the frequency changes in the striatum and reticular formation
(Figure 7). It is obviously that a potentiation mechanism has taken place. The
same feature is observed when looking at the second hour after administration.
In particular, when looking at the results obtained in the striatum and reticular
formation, the highly significant attenuation of alpha1 waves cannot be ex-
plained by a simple additive effect. We emphasize that the combination of Zy-
namite® with a dosage of caffeine fifty times lower results in a tremendous at-
tenuation of all frequencies except for spectral gamma power in all brain regions
beginning in the second hour after administration. Thus, if most caffeine is re-
placed by Zynamite® but at least 2% of caffeine is retained, this large increase in
stimulation can be achieved.
The results of the field potential approach are corroborated by the results
from the ex vivo trial using the hippocampus slice in vitro to follow excitability
changes in the presence of 0.5 mg/kg of caffeine, 25 mg/kg of Zynamite® or their
combination in comparison to Placebo after daily administration for one week.
This approach was undertaken in order to demonstrate that CNS-active bioac-
tive compounds from Zynamite® are able to pass the blood brain barrier and ex-
ert their action by changing the excitability state of the hippocampus after daily
administration of the four preparations. The results are in favour of such an ac-
tion since Zynamite® alone and in combination with caffeine induces increases
of the amplitude of the population spike in the presence of single shock stimula-
tion and theta burst stimulation, whereas caffeine alone only increases the pop-
ulation spike during theta burst stimulation leading to long-term potentiation.
Long-term potentiation relates to space and time dependent memory [16]. From
this it is evident, that caffeine as well as Zynamite® act in a similar way and have
potential to improve cognitive functions. Based on the similarity of their action
with respect to long-term potentiation, a replacement of caffeine by Zynamite®
makes sense.
5. Conclusion
In conclusion,
in vivo
administration of Zynamite® or caffeine displayed a simi-
lar action on the central nervous system with respect to changing the frequency
pattern of brain regional field potentials and
ex vivo
by changing the excitability
of the hippocampus of rats. A combination of both revealed over-additive or
potentiating effects in both animal models pointing to a synergy between Zyna-
mite® and caffeine. Zynamite® has potential as a CNS-activating nutraceutical
that could be used to replace caffeine.
W. Dimpfel et al.
DOI:
10.4236/fns.2018.95039 517 Food and Nutrition
Sciences
Acknowledgements
Mrs. Ingrid K. Keplinger-Dimpfel and Mrs. Chiegoua Dipah Gwladys Nina are
thanked for performing quality control critically proof reading of the manuscript.
Conflict of Interest
The study was financially supported by Nektium S.L., Las Palmas, Gran Canaria.
Drs. Nigel Gericke and Julia Wiebe are employed by Nektium Pharma and had
no role in the conduct of the experimental work or analysis of the results.
References
[1] Shah, K.A., Patel, M.B., Patel, R.J. and Parmar, P.K. (2010)
Mangifera indica
(Man-
go).
Pharmacognosy Reviews
, 4, 42-48. https://doi.org/10.4103/0973-7847.65325
[2] Dimpfel, W., Spüler, M. and Nickel, B. (1986) Radioelectroencephalography
(Tele-Stereo-EEG) in the Rat as a Pharmacological Model to Differentiate the Cen-
tral Action of Flupirtine from That of Opiates, Diazepam and Phenobarbital.
Neu-
ropsychobiology
, 16, 163-168. https://doi.org/10.1159/000118319
[3] Dimpfel, W. (2003) Preclinical Database of Pharmaco-Specific rat EEG Fingerprints
(Tele-Stereo-EEG).
European Journal of Medical Research
, 8,199-207.
[4] Dimpfel, W. (2013) Pharmacological Classification of Herbal Extracts by Means of
Comparison to Spectral EEG Signatures Induced by Synthetic Drugs in the Freely
Moving Rat.
Journal of Ethnopharmacology
, 149, 583-589.
https://doi.org/10.1016/j.jep.2013.07.029
[5] Lynch, G. and Schubert, P. (1980) The Use of
in-Vitro
Brain Slices for Multidis-
ciplnary Studies of Synaptic Function.
Annual Review of Neuroscience
, 3, 1-22.
https://doi.org/10.1146/annurev.ne.03.030180.000245
[6] Dingledine, R. (1984) Brain Slices. Plenum Press, New York, London.
https://doi.org/10.1007/978-1-4684-4583-1
[7] Dimpfel, W. (1996) Effect of Thioctic Acid on Pyramidal Cell Responses in the Rat
Hippocampus
in Vitro
.
European Journal of Medical Research
, 1, 523-527.
[8] Dimpfel, W. and Biller, A. (2015) Mechanism of Action of Low Dose Preparations
of Coffea Arabica, Gelsemium and Veratrum Based on
in Vivo
and
in Vitro
Neu-
rophysiological Findings.
Journal of Behavioral and Brain Science
, 5, 368-380.
https://doi.org/10.4236/jbbs.2015.59036
[9] Haas, H.L., Schaerer, B. and Vosmansky, M. (1979) A Simple Perfusion Chamber
for the Study of Nervous Tissue Slices
in Vitro
.
Journal of Neuroscience Methods
, 1,
323-325. https://doi.org/10.1016/0165-0270(79)90021-9
[10] Schiff, S.J. and Somjen, G.G. (1985) The Effects of Temperature on Synaptic
Transmission in Hippocampal Tissue Slices.
Brain Research
, 345, 279-284.
https://doi.org/10.1016/0006-8993(85)91004-2
[11] Dimpfel, W., Schombert, L., Vega-Morales, T. and Wiebe, J. (2016) Neuropharma-
cological Characterization of Extracts from Rhodiolarosea, Oenotheraparadoxa and
Paulliniacupana in Comparison to Caffeine.
Pharmacology & Pharmacy
, 7, 290-303.
https://doi.org/10.4236/pp.2016.77036
[12] Dimpfel, W. (2015) Drug Discovery and Translational Medicine Based on Neuro-
physiological Techniques. A Holistic Approach to Saving Animals. Books on De-
mand, Norderstedt.
W. Dimpfel et al.
DOI:
10.4236/fns.2018.95039 518 Food and Nutrition
Sciences
[13] Pardo Andreu, G.L., Maurmann, N., Reolon, G.K., De Farias, C.B., Schwartsmann,
G., Delgado, R. and Roesler, R. (2010) Mangiferin, a Naturally Occurring Glucoxil-
xanthone Improves Long-Term Object Recognition Memory in Rats.
European
Journal of Pharmacology
, 635, 124-128. https://doi.org/10.1016/j.ejphar.2010.03.011
[14] Kamalla, A.K., Ramasamy, M.K., Inampudi, R.J., Dubey, G.P., Agrawal, A. and Kal-
liapan, I. (2015) Comparative Pharmacokinetic Study of Mangiferin after Oral Ad-
ministration of Pure Mangiferin and US Patented Polyherbal Formulation to Rats.
AAPS PharmSciTech
, 16, 250-8. https://doi.org/10.1208/s12249-014-0206-8
[15] Dimpfel, W. (2007) Characterization of Atypical Antipsychotic Drugs by a Late De-
crease of Striatal Alpha1 Spectral Power in the Electropharmacogram of Freely
Moving Rats.
British Journal of Pharmacology
, 152, 538-548.
https://doi.org/10.1038/sj.bjp.0707427
[16] Cortese, G.P., Olin, A., O’Riordan, K., Hullinger, R. and Burger, C. (2018) Envi-
ronmental Enrichment Improves Hippocampal Function in Aged Rats by Enhanc-
ing Learning and Memory, LTP, and mGluR5-Homer1c Activity.
Neurobiology of
Aging
, 63, 1-11. https://doi.org/10.1016/j.neurobiolaging.2017.11.004
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