Glycative Stress Research
Online edition : ISSN 2188-3610
Print edition : ISSN 2188-3602
Received : November 27, 2020
Accepted : April 5, 2020
Published online : June 30, 2020
doi:10.24659/gsr.7. 2_123

Original article

Effect of the newly developed articulatory panels (Aural Sonic):
A pilot clinical trial.
Manabu Fukushima 1), Shiori Uenaka 2), Masayuki Yagi 2), Wakako Takabe 1), Yoshikazu Yonei 1),
1) Department of Media Technologies, School of Engineering, Nippon Bunri University, Oita, Japan2) Anti-Aging Medical Research Center and Glycative Stress Research Center, Faculty of Life and Medical Sciences,
Doshisha University, Kyoto, Japan

Abstract

Purpose: Since the articulation panel (Aural Sonic R ) has a characteristic of absorbing unpleasant sound and leaving
a comfortable sound, stress reduction and relaxation effects are expected. In this study, we examined the effect of theinstallation of the articulator panel (test product) in the bedroom on sleep quality using the melatonin metabolite 6-sulfatoxymelatonin (SaMT) as an index.
Methods: The first trial was an uncontrolled open pilot study of 10 male students (26.4 ± 8.7 years), in which a test panel
was set up in the bedroom at home. The second trial was performed as a controlled shift comparison trial of 6 male andone female students (27.3 ± 11.6 years), in which SaMT was measured at a training camp facility with a constant sleep
environment while monitoring illuminance and temperature with a sleep environment measurement device, then the effectbetween the control and test panel was compared.
Results: In the first trial, the amount of urine discharged SaMT during the night was −13.4% lower when using the test panel(p = 0.046), which was determined to be due to the difference in illumination conditions. In the second test, it was confirmedthat illuminance and temperature were constant, the 24-hour urinary SaMT concentration was significantly higher (+54.7%)
when using the test panel (38.2 ± 5.6 ng/mL) than when using the control panel (24.7 ± 2.3 ng/mL, p = 0.028).
Conclusion: It was suggested that the installation of the articulation panel in the bedroom could improve the sleep quality
with increased melatonin excretion, due to the reduction of unpleasant noise, improving sleep environment. Since melatoninsecretion is affected by the sleep environment, it is necessary to evaluate it under constant conditions such as room
temperature and illuminance.

KEY WORDS: articulation material, sleep quality, melatonin, 6-sulfatoxy-melatonin (SaMT)

Introduction

The drop of the quality of sleep is one of the age-related
deteriorations. The Japanese have a tendency towards a chroniclack of sleep from children to adults 1-3). Indefinite complaints
due to lack of sleep are common not only in middle-aged
people but also in childhood and puberty, which is associatedwith various lifestyle-related diseases and mental healthissues 4-8). Maintaining high sleep quality is very importantfrom a viewpoint of preventive medicine.
There is a bidirectional link between sleep and glucose

metabolism. Approximately 40 % of patients with diabetes,
a representative disease with high glycation stress, havesome sleep disorders 9, 10). Obesity 11-13) and diabetes 14-16) arefrequently associated with sleep apnea syndrome (SAS), a
typical disorder with poor sleep quality. In order to reduce
glycation stress, it is necessary to concurrently consider theprevention and treatment of abnormal glucose metabolism
and sleep disorders.
A comfortable environment is important to keep our sleep
quality high. In addition to temperature, humidity, andilluminance, it is desirable to use moderate load exercise 17)

Corresponding to: Manabu Fukushima, PhD
Department of Media Technologies, School of Engineering, Nippon Bunri University
1727 Ichigi, Oita, 870 - 0397 Japan

TEL: + 81-97-524-2748 FAX: +81-97-592-0911 e-mail: fukushima@nbu.ac.jp
Co-authors: Uenaka S, ctud2025@mail4.doshisha.ac.jp; Yagi M, myagi@mail.doshsisha.ac.jp;
Takabe W, wtakabe@mail.doshsisha.ac.jp; Yonei Y, yyonei@mail.doshsisha.ac.jp_ 123 _

Glycative Stress Research 2020; 7 ( 2) : 123-131(c) Society for Glycative Stress Research

The Newly Developed Articulatory Panels and Sleep Quality

and bedding suitable for individual conditions 18-20). In addition,
noise is one of the factors that hinder sleep. Noise reduces
sleep quality, while a completely silent environment, sometimes
worrying about heartbeat, may interfere with falling asleep.
It is expected that a soothing sound will provide a
comfortable sleep, however, there are many unclear points
about the sound, wavelength, sound pressure, and wavelength
fluctuation. In recent years, low frequency noise generated
from wind power generation, “eco cute”, and the like has also
become a problem, countermeasures against which are an
issue. In the present study, we have used a panel with acoustic
characteristics that absorbs unpleasant sounds and reflects
comfortable sounds (Aural Sonic T M : Tokyo Steel IndustrialCo., Ltd., Kita-ku, Tokyo, Japan) 21), and the effect of thepanel on sleep quality was examined.

Method

1. An open-label, uncontrolled pilot study(measured at home).
The test subjects were 10 healthy male students of Nippon
Bunri University, and the effect of using the test panel 21) athome on sleep was verified. The test panels were provided
by Tokyo Steel Industrial Co., Ltd. Subjects were 26.4 ± 8.7
years of age, 169.3 ± 6.9 cm of height, 63.8 ± 10. 2 kg ofbody weight, and 22.2 ± 2.7 kg/m 2 of body mass index(BMI). Two test days were set during the test period fromJanuary to March in 2017, and the following items werecompared with respect to the effects of sleep when the test
panel was used and when it was not used. Examination
items included a background survey, blood pressure, bodycomposition (body weight, body fat percentage), 6-sulfatoxymelatonin (SaMT) 22) as a melatonin metaboliteand creatinine

Fig. 1.

(Cre) in the nocturnal urinary bladder storage specimen(early morning first urine), which were measured by LSI
Medience (Chiyoda-ku, Tokyo, Japan). Regarding the earlymorning first urine, the urine volume and the time durationof urinary bladder storage (from the time of the last urine
to time of the first urine in the next day) were recorded. The
indicated parameters (degree of sleep / sleep time) by Sleep
CycleR were also compared. Sleep CycleR (Sleep Cycle AB,
Gothenburg, Sweden) was downloaded and used in a smart
phone equipped with a 3 dimension acceleration sensor.
There were no dropouts, and all cases were analyzed.

2. Control shift comparison test with illumination
monitoring (measured at the camp facility).
The illuminance in the bedroom after the lights wereturned off was set to a constant condition so that theilluminance during sleep did not affect melatonin secretion,and the test was conducted using control panels and test
panels. The sleep environment (temperature, illuminance,
floor vibration) was measured over time using a self-madesleep environment measurement device.
As a control panel, a panel similar in appearance tothe test panel and having no articulation function was used.
Subjects were 6 (5 males and 1 female), 27.3 ± 11.6 years ofage, 170.5 ± 8.1 cm of height, 61.7 ± 11. 5 kg of body weight,
and 21.1 ± 2.9 kg/m2 of BMI.
In September 2017, we had a three-night four-day training
camp and the study was performed at the accommodation
facility of the university ( Fig. 1). Among the measurement
items, SaMT was measured using first morning urine samples
and 24-hour urine samples, the rest was the same as theprevious study “1. An open-label, uncontrolled pilot study”.
There were no dropouts, and all cases were analyzed.

Fig. 1. Test schedule: Second test

_ 12 4 _12

Glycative Stress Research

Sleep environment measurement device

Figure 2 shows the configuration of the device. In thedevice, a temperature sensor, an illuminance sensor, andan acceleration sensor were connected to the main unit,
measured information was transmitted to a remote monitor
via WiFi, and recorded on a USB memory stick connectedto the remote monitor. In order not to disturb the sleep
environment, a sensor was attached to my RIO and housed inFig. (1.
Fig. 3). The equipment was set at the bedsidea wooden caseand the remote monitor was located in a separate room.

Fig. 2.

Ethical considerations
This study was conducted as an exercise-style course aspart of a university education program. Participating students
chose this subject voluntarily and participated in the practiceof assembling the sleep environment measurement device
and in the practical training of environment measurement.
No invasive tests were performed. The participants were
informed about the ethics of this research.

Fig. 2. The configuration of the sleep environment monitering device

13

Fig. 3. A picture of the sleep environment
monitering device
Fig. 3.

_ 125 _

The Newly Developed Articulatory Panels and Sleep Quality

Statistical analysis
A paired t-test when the number was 10 or more, and a
Wilcoxon signed rank test when the number was less than 10,
were used for comparative analysis, which was performed byusing SPSS Statics25 (IBM Japan, Minato-ku, Tokyo, Japan).

2. Control shift comparison test with illumination
monitoring (measured at the camp facility).

Results

1. An open-label, uncontrolled pilot study(measured at home).

Figure 4 shows the results of urine SaMT concentration
corrected by Cre (ng/mg Cre), urinary discharged SaMT
(urine SaMT [ng/mL] × the volume of the first urine[mL] /storage time [h]) and sleep duration with and without using
the test panel. Urine dischaged SaMT with the test panel(1,905 ± 172 ng/hr) was siginificantly lower (−13.4 %) than

a)

30
35
25
30
35
20
25
30
15
20
25
10
15
20
5
10
15
0
5
10
0
5
2,500

Figures 6 & 7 show the result image of “Sleep Cycle R ”
and monitored data of room temperature and illuminationof each subject. Temperature changes were similar in all
bedrooms. The illuminance in the bedroom was kept below
2 lux while the lights were off. The sleep environment on thesecond and third days was almost the same.
Figure 8 shows results of the urine SaMT concentration
corrected by Cre, SaMT in 24 -hour urine samples, urinarydischarged SaMT (urine SaMT [ng/mL] × the volume of
the first urine [mL] / storage time [h]), and sleep duration
using the control panel and the test panel. SaMT in 24-hoururine samples using the test panel (38.2 ± 5.6 ng/mL) was
significantly higher (+54.7%) than that using the control
panel (24.7 ± 2.3 ng/mL, p = 0.028).
There were no significant differences in pleasant sleep
index or sleep duration indicated by Sleep CycleR between
the conditions using the test panel and the control panel(Fig. 9).

a)

P = 0.046

0
2,000
2,500

P = 0.046

1,500
2,000
2,500
1,000
1,500
2,000
500
1,000
1,500
5000
1,000
400
0
500

400
300
200
300
200
100

100
0
0

Panel (- )Panel (+)

Panel (- )Panel (+)

Panel (- )Panel (+)

60
70
50
60
40
50
30
40
20
30
10
20
0
10
4000

b)

400
300
0

200
1000

70

Pleasant
sleep
index
Pleasant
sleep
index

P = 0.046

Sleep
duration
Sleep
duration(min)(min)c)

35

durationdischarged
Sa-MT
Cre-corrected
Sa-MT
SleepSleep
duration
UrineUrine
discharged
Sa-MT
Cre-corrected
Sa-MT
Sleep
duration
Urine
discharged
Sa-MT
Cre-corrected
Sa-MT(ng/h)(ng/mgCre) Cre)(min)(min) (min)(ng/h)(ng/mgCre)(ng/h)(ng/mgb)that without the panel (2,199 ± 150 ng/hr, p = 0.046). There
were no significant difference in SaMT concentration or
sleep duration.
Comparison analysis was also performed on the parameter
indicated by Sleep CycleR (Fig. 5). There were no significant
differences in pleasant sleep index or sleep duration.

400
300
300
200
200
100
100
0
0

Fig. 4. Urine SaMT: First testa) Urine SaMT consentration corrected by Cre. b) Urine discharged
SaMT. c) Sleep duration. Results are expresses as mean ± SEM, n = 10,

paired t test. SaMT, 6-sulfatoxymelatonin, one of melatonin metabolites;
Cre, creatinine; SEM, standard error mean.

Panel (- )Panel (+)

Panel (- )Panel (+)

Fig. 5. “ Pleasant sleep index ” and “ Sleep duration ”
by “ Sleep CycleR ” : First testa) “ Pleasant sleep index”. b) “Sleep duration”. Parameters are analyzed
by “ Sleep Cycle R ”. Results are expresses as mean ± SEM, n = 8. Twocases excluded due to the unclear image data from Sleep CycleR . SEM,
standard error mean.

_ 12 6 _Glycative Stress Research

16
16Fig. 6. The sleep environment data in the 2nd day monitering with control panels: Second test

Fig. 6.

a) “Sleep CycleR ” image graph. b) Temperature. c) Luminosity. Temperature and luminosity measured by
the sleep environment monitering device.

Fig. 6.

Fig. 7.

Fig. 7. The sleep environment data in the 3rd day monitering with test panels: Second testa) “Sleep CycleR ” image graph. b) Temperature. c) Luminosity. Temperature and luminosity measured by

Fig. 7.

the sleep environment monitering device.

_ 127 _

The Newly Developed Articulatory Panels and Sleep Quality

Urine
discharged
Sa-MT
Urine
discharged
Sa-MT(ng/h)(ng/h)
Urine
discharged
Sa-MT
Urine
discharged
Sa-MT(ng/h)(ng/h)

Cre-corrected
Sa-MT
Cre-corrected
Sa-MT(ng/mgCre)(ng/mgCre)
Cre-corrected
Sa-MT
Cre-corrected
Sa-MT(ng/mgCre)(ng/mg
Cre)

50 50
50 50
40 40
40 40
30 30
30 30
20 20
20 20
10 10
10 10
0 0
0 0

4,000
4,000
4,000
4,000

3,000
3,000
3,000
3,000

2,000
2,000
2,000
2,000
1,000
1,000
1,000
1,000

P =P0.028= 0.028= 0.028
P =P0.028

d)

Sleep
duration
Sleep
duration
(min)
(min)
Sleep
duration
Sleep duration
(min)
(min)

b)

c)

25 25
25 25
20 20
20 20
15 15
15 15
10 10
10 10
5 5
5 5
0 0
0 0

Sa-MT
Sa-MT
in in
24-hour
24-hoururine
urine(ng/mL)(ng/mL)Sa-MT
in in
24-hoururine
Sa-MT
24-hoururine(ng/mL)(ng/mL)a)Control
Controlpanel
panel
Control
panel
Controlpanel

TestTest
panel
panel
panel
TestTest
panel

0
0

0
0

500 500
500 500
400 400
400 400
300 300
300 300
200 200
200 200
100 100
100 100
0 0
0 0

Control
Controlpanel
panel
Control
panel
Controlpanel

TestTest
panel
panel
panel
TestTest
panel

Fig. 8. Urine SaMT: Second testa) Urine SaMT consentration corrected by Cre. b) SaMT concentration in 24 -hour urine. c) Urine discharged SaMT. d) Sleep duration. Results
are expresses as mean ± SEM, n = 6, Wilcoxon signed-rank test. SaMT, 6 - sulfatoxymelatonin, one of melatonin metabolites; Cre, creatinine;
SEM, standard error mean.

a)Discussion

Pleasant
Pleasant
sleep
sleep
index
index

80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
0
0
500

Sleep
Sleep
duration
duration
(min)
(min)

b)

500
400
400
300
300
200
200
100
100
0
0

Fig. 9. “ Pleasant sleep index ” and “ Sleep duration ” by“ Sleep CycleR ”: Second testa) “Pleasant sleep index”. b) “Sleep duration”. Parameters are analyzed

by “ Sleep Cycle R ”. Results are expresses as mean ± SEM, n = 6. SEM,
standard error mean.

In the present study, we examined the effects of theenvironment using the articulation panel, a test product,on sleep quality using students as subjects and melatonin
metabolites as indicators. Articulating panels, which weredeveloped for homes and offices, absorb sounds that are
unpleasant for humans and leave comfortable sounds, thusincreasing alpha waves by electroencephalography and is
expected to reduce stress and increase relaxation 21). There areseveral ways to assess sleep quality, and as one of them, urine
SaMT, a melatonin metabolite, was used as an index. Sleep
quality is sensitive to room temperature and illuminance,
especially in light environments, which suppresses melatoninsecretion, therefore we made our own sleep environment
measurement device and used it for experiments.
The result of the first experiment (An open-label,
uncontrolled pilot study) that urine discharged SaMT islower when using the test panel (−13.4%) was different than
expected. Previous studies have reported that the excretionof SaMT in urine varies with changes in room temperatureduring sleep 23). Illuminance strongly affects melatoninsecretion, which is suppressed in bright conditions 24). Since,in the first test, measurements were taken in each homebedroom, we speculated that the cause was that the sleep
environment, such as illuminance, temperature, and bedding
was different for each subject.
The second test (Control shift comparison test with
illumination monitoring) was conducted in a training
camp, and SaMT measurement was performed under the_ 12 8 _Glycative Stress Research

condition that the subject's sleep environment (illuminance,
temperature, and bedding) was fixed. Using a continuous
monitoring device, it was confirmed that the illuminanceand humidity were almost the same, and that the illuminancewas kept below 2 lux when the lights were turned off. The
studies performed under these conditions showed that SaMTin 24-hour urine samples increased by more than 50% withthe use of test panels. These results suggest that the use ofarticulatory panels may have increased melatonin secretion.

SaMT
The amount of urinary SaMT excretion is known toreflect the amount of melatonin secretion 22, 23). SaMT is
reduced in patients with diabetes 25) or growth hormone
deficiency 26), and in workers who work night shifts 27).
Evaluation of melatonin secretion and sleep quality
using SaMT as an index has not yet been widely conductedin Japan.
According to reports in Japan, the urinary SaMT
production of 6 female nurses (average age 29.7 years) was,during the day shift, 660 ng/ hr (07: 00 – 23: 00) and 2,580
ng/hr (23: 00 – 07: 00), while, during night shifts, were 640
ng/hr (07: 00 – 23: 00) and 1,420 ng/ hr (23 : 00 – 07: 00) 28).
The time in parentheses indicates the time from the start tothe end of urine collection. Urinary SaMT production was
reduced by about 45 % during the night shift. Since a large
amount of SaMT is generated from late night to morning,
even during the night shift, it can be seen that melatoninsecretion is secreted according to the biological clock rather
than the lifestyle of sleeping.
In a study measuring urinary SaMT production inelderly living independently, serum cortisol was lower,
insulin-like growth factor -I (IGF-I) was higher, and urine
discharged SaMT was higher with higher physical activity 17).
The amount of urine discharged SaMT in 23 elderly
people (10 males, 13 females, age 78.7 ± 6.1 years old) was,when divided into three tertiles according to physical activity,
1,081.7 ± 258. 5 ng/hr in a high activity group, 841.0 ± 294.5
ng/hr in a medium activity group and 724.2 ± 205.2 ng/ hr
in a low activity group (no significant difference between
groups) 17). Compared to the value of 2,487.0 ± 193.2 ng/hr
for 6 students (27.3 ± 11.6 years) in this test, the value islower in the elderly.
Urinary SaMT concentration (Cre corrected value) in 12
subjects (4 males, 8 females, 51.9 ± 7. 2 years old) was 11.13± 3.72 ng/mg Cre 20). The value of 11. 56 ± 2.94 ng/mg Cre in
6 students (27.3 ± 11.6 years old) in this study was similar tothat in middle-aged and elderly people.
If such data can be accumulated, it is expected thaturinary SaMT measurement will serve as an evaluation index
for melatonin secretion.

Index by “Sleep Cycle R”

This study used the “Sleep CycleR ”smart phone application,commonly used in the smartphone market, to analyze a pleasantsleep index and sleep duration. However, it is unknown how
pleasant sleep is defined. In the two trials, no difference wasseen in the “pleasant sleep index” with or without the use of
the test panel. SaMT may be more sensitive in assessing sleep
quality.

Possible mechanism
The mechanism by which the use of the test panel
increased melatonin secretion is speculated as follows. Since
the articulation panel has an effect of absorbing unpleasantsounds and leaving comfortable sounds, it is consideredthat unpleasant sound stress on the brain was reduced andthe sleep environment was improved. We have previously
reported that the use of comfortable bedding improved thesleep environment, resulting in increased secretion of growth
hormone / IGF-I 18), decreased serum cortisol 19), and increased
dehydroepiandrosterone (DHEA) production 19).
The following pathways are assumed for the melatonin
synthesis pathway 24). Light stimulation received by the retina
is transmitted mainly to the suprachiasmatic nucleus (SCN),
the site of the circadian clock, via the retina-hypothalamus
tract, thus synchronizing the phase of the circadian clockwith the external light cycle (24-hour cycle). The time
information generated in the SCN is transmitted to the pineal
gland via nerve fibers, through the maxillary ganglion. In
this pathway, the nerve activity of the maxillary ganglia
is suppressed by light stimulation, so that the activity is
actually only performed at night without light stimulation.
Noradrenaline is secreted from nerve endings derived
from the maxillary ganglion, which stimulates pineal
cells, mainly via β receptors, and promotes the synthesis ofcAMP, a second messenger, thus activating allylalkylamine
N-acetyltransferase activity (AANAT), which is the ratelimiting enzyme of melatonin synthesis. In the daytime,
AANAT is minimally activated, and the pineal gland andblood melatonin concentration show a diurnal variation thatis high at night and low in the daytime.
On the other hand, the blood concentration of cortisol
is regulated by the circadian rhythm, and is highest in
the morning, stays high from morning to afternoon, andgradually decreases from afternoon then showing low levels
until habitual sleep onset 29). Excessive mental and physicalstress causes an increase in cortisol concentration, resulting
in sleep difficulty such as difficulty falling asleep.
Following circadian rhythm, cortisol levels during
sleep remain relatively low and rise rapidly 2 -3 hours before
habitual wake-up time 29). Sleep has an inhibitory effect on
cortisol secretion 30), sleep disruption (sleep deprivation) andinsomnia in patients causes increased cortisol secretionand pulsed secretion 31, 32). Elevated cortisol levels at dawn,
especially pulsed secretions, are said to be deeply involved inalertness.
It is known that an increase in cortisol causes a decrease
in melatonin secretion 33 -36), while, if stress is alleviated byproviding a comfortable sleeping environment, cortisol
secretion is reduced and melatonin secretion is expected torecover. In this study, it is possible that the use of articulatory
panels reduced uncomfortable sound stress, resulting in adecrease in cortisol levels during sleep and restoration ofmelatonin secretion.

Conclusion
As verification results of the effect of articulating panelsin the bedroom on sleep quality examined using the melatonin
metabolite SaMT as an index, the panel suggested that_ 12 9 _The Newly Developed Articulatory Panels and Sleep Quality

discomfort noise was reduced, urinary SaMT excretion
increased, and sleep quality could be improved. In addition,
since melatonin secretion is affected by the sleep environment,
it is necessary to evaluate test results under constant conditions
such as room temperature and illuminance.

Conflict of Interest Statement
The present study was partly supported by Tokyo Steel
Industrial Co., Ltd.

Acknowledgement
This work was supported by JSPS KAKENHI Grant
Number #26350917. The outline of this study was presented
at the 16th Meeting of Glycative Stress Research on October18, 2018, Tokyo.

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