Sleep aids

Abstract

To provide a composition for improving sleep during naps. [Solution] A composition for improving sleep during naps, comprising geranyl acetate as an active ingredient, and a method for improving sleep during naps using geranyl acetate, and a method for improving the sleep environment during naps in a living space.

Description

Technical Field

[0001] The present invention relates to a sleep improvement agent using fragrance components.

Background Art

[0002] In recent years, it has been said that taking an active nap (power nap) during the day is effective in improving work performance. Therefore, some companies have started providing nap spaces in offices. However, napping in an office or the like is not always comfortable and may not lead to an improvement in performance. There is a need for a method to improve sleep during napping and enhance the effect of napping.

[0003] On the other hand, the number of people suffering from sleep disorders such as insomnia is increasing, and various studies have been conducted on methods for improving sleep disorders. Patent Document 1 discloses a fragrance composition for sleep improvement, a cosmetic using the same, and a sleep improvement method, which have an excellent effect of providing a sleep improvement effect by containing cypress oil and lavender oil, particularly shortening the sleep induction time to improve sleep induction disorders, or reducing the number of awakenings during sleep to improve deep sleep disorders. Patent Document 2 discloses an aqueous solution for sleep improvement that exhibits the fragrance of hamanasu petals and has an effect of extending the deep sleep time. Patent Document 3 discloses a transdermal absorption type composition for inducing sleep containing geranyl acetate-based eucalyptus oil as an active ingredient.

[0004] However, what is disclosed in Patent Documents 1 to 3 is a technology for improving sleep disorders and does not show any effect on sleep during napping.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

[0006] The object of this invention is to provide a composition for sleep improvement agents used during naps. [Means for solving the problem]

[0007] The inventors of this invention conducted extensive research to solve the above problems and, as a result, discovered that inhaling geranyl acetate as a fragrance component can improve sleep during naps, thus completing the present invention.

[0008] In other words, the present invention encompasses the following: [1] A composition for improving sleep during naps, containing geranyl acetate as an active ingredient. [2] The composition described in [1] above, which is a fragrance composition. [3] The composition according to [1] or [2] above for at least one selected from the group consisting of promoting increased vitality after napping, promoting reduced drowsiness, promoting recovery from fatigue, and suppressing increased parasympathetic nerve activity during napping. [4] A method for improving sleep during a nap, comprising administering geranyl acetate intranasally to a subject during a nap, A method for producing at least one selected from the group consisting of promoting increased vitality after napping, promoting reduced drowsiness, promoting recovery from fatigue, and suppressing increased parasympathetic nervous system activity during napping. [5] A method for improving the sleep environment during napping in a living space, comprising releasing geranyl acetate into the living space. [Effects of the Invention]

[0009] According to the present invention, it is possible to improve sleep during naps and enhance the effects of naps, leading to improved performance after the nap. [Brief explanation of the drawing]

[0010] [Figure 1]Figure 1 is a photograph showing the sheet used as a napping area in an evaluation test to investigate the effects of fragrance components on napping. Figure 1A: Condition of the sheet when eyes are open and at rest; Figure 1B: Condition of the sheet when napping. [Figure 2] Figure 2 shows the test protocol for the evaluation test. [Figure 3] Figure 3 shows the overall changes in RAS activity before and after napping, based on a RAS questionnaire survey. [Figure 4] Figure 4 shows the changes in sleepiness before and after napping, based on the RAS questionnaire survey. [Figure 5] Figure 5 shows the change in pNN 50% based on electrocardiogram measurements during nap time compared to before nap time. [Figure 6] Figure 6 shows the changes in fatigue levels before and after napping. A: Percentage of subjects whose flicker value improved after napping in the flicker value measurement. B: Percentage of subjects whose reaction time improved after napping in the Stroop test. [Modes for carrying out the invention]

[0011] The present invention will be described in detail below. This invention relates to sleep improvement techniques that can improve sleep, particularly sleep during naps. More specifically, this invention provides a composition and method for improving sleep during naps using geranyl acetate.

[0012] Geranyl acetate is a volatile substance and a fragrance component characterized by a fruity, citrusy scent. Geranyl acetate can be extracted from natural essential oils by distillation, or it can be synthesized, for example, by a condensation reaction between the natural terpenoid geraniol and acetic acid.

[0013] In the present invention, geranyl acetate can be used as a sleep improving agent for improving sleep, particularly sleep during a short nap. In the present invention, "short nap" means a short period of sleep taken temporarily for the purpose of fatigue recovery or drowsiness relief during the active time of the subject (for example, during daytime or night shift), and includes taking a nap during daytime or taking a short nap during night shift. The "short nap" in the present invention is not limited to the following, but is preferably within 100 minutes, more preferably within 60 minutes, still more preferably within 30 minutes, and can be, for example, sleep of 10 to 30 minutes, or 15 to 25 minutes. In the present invention, by applying geranyl acetate to the subject during a short nap (specifically, allowing the subject to smell geranyl acetate as a fragrance component), the sleep during a short nap can be improved.

[0014] The improvement of sleep during a short nap by geranyl acetate in the present invention brings about an improvement in the activity performance after the short nap. The improvement of sleep during a short nap by geranyl acetate in the present invention can bring about at least one selected from the group consisting of, for example, promotion of increased vitality after a short nap, promotion of decreased drowsiness, promotion of fatigue recovery, and suppression of enhanced parasympathetic nerve activity during a short nap.

[0015] The promotion of increased vitality after a short nap by geranyl acetate in the present invention refers to a significant increase in vitality (such as activity desire and physical strength) after a short nap as compared with before the short nap. The promotion of increased vitality after a short nap by geranyl acetate in the present invention can be shown, for example, when geranyl acetate is applied during a short nap, the increase level of the sensation scale "overall activity" after a short nap based on a questionnaire (RAS questionnaire) using RAS (Roken Arousal Scale; a subjective evaluation index for fatigue and arousal; a subjective evaluation index developed by the Industrial Science and Technology Research and Development Project "Human Sensation Measurement Application Technology"; from the "Human Sensation Database for Workplace Environment Diagnosis" of the Human Life Engineering Research Center, Incorporated Administrative Agency) is greater than the increase level of "overall activity" after a short nap as compared with before the short nap when no fragrance component is applied during a short nap. Details of the RAS questionnaire are described in the examples described later in the present application, particularly in Tables 2 and 3.

[0016] The promotion of reducing drowsiness after short naps by geranyl acetate in the present invention refers to that the drowsiness after short naps is significantly reduced compared to before short naps. The promotion of reducing drowsiness after short naps by geranyl acetate in the present invention can be shown, for example, when geranyl acetate is applied during short naps, the reduction level of the sensation scale "drowsiness" after short naps compared to before short naps based on a questionnaire (RAS questionnaire; refer to Tables 2 and 3 in the examples of the present application) using the RAS (Roken Arousal Scale; subjective evaluation index for fatigue and arousal; a subjective evaluation index developed by the Industrial Science and Technology Research and Development Project "Human Sensation Measurement Application Technology"; from the "Human Sensation Database for Workplace Environment Diagnosis" of the Human Life Engineering Research Center, Incorporated Association) is greater than the reduction level of "drowsiness" after short naps compared to before short naps when no fragrance component is applied during short naps.

[0017] The promotion of fatigue recovery after short naps by geranyl acetate in the present invention refers to that the degree of fatigue after short naps, for example, the degree of fatigue including mental fatigue degree, is significantly reduced compared to before short naps. The promotion of fatigue recovery after short naps by geranyl acetate in the present invention can be shown, for example, when geranyl acetate is applied during short naps, the improvement of the flicker value after short naps compared to before short naps based on flicker value measurement (for example, the ratio of subjects in whom an increase in the flicker value after short naps is observed) is greater than the improvement of the flicker value after short naps compared to before short naps when no fragrance component is applied during short naps (for example, the ratio of subjects in whom an increase in the flicker value after short naps is observed). Alternatively, the promotion of fatigue recovery after short naps by geranyl acetate in the invention can be shown, for example, when geranyl acetate is applied during short naps, the improvement of the reaction after short naps compared to before short naps based on the Stroop test (for example, the ratio of subjects in whom a decrease in the reaction time of the Stroop test after short naps is observed) is greater than the improvement of the reaction after short naps compared to before short naps when no fragrance component is applied during short naps (for example, the ratio of subjects in whom a decrease in the reaction time of the Stroop test after short naps is observed).

[0018] In one embodiment, the promotion of fatigue recovery after napping by geranyl acetate in the present invention may result in both an improvement in the flicker value after napping and an improvement in the response to the Stroop test after napping compared to a case where no fragrance component is applied during napping, or at least one of these may be superior. The improvement in the flicker value and the improvement in the response to the Stroop test can be suitably used as indicators of recovery (improvement) in mental fatigue.

[0019] Details of flicker value measurement are described in the embodiments below in this application. Flicker value measurement can be performed using any flicker value measuring instrument such as the Flicker Value Measuring Instrument Type II (Automatic Type) (TKK-501C, Takei Kiki Kogyo). In flicker value measurement, the flashing speed (frequency) of the light can be gradually increased, and the frequency (Hz) at which the subject can no longer perceive the "flicker" can be taken as the flicker value (ascending method). Alternatively, the flashing speed (frequency) of the light can be gradually decreased from a high frequency, and the frequency (Hz) at which the subject can perceive the "flicker" can be taken as the flicker value (descending method).

[0020] Details of the Stroop test are described in the embodiments below in this application. In the Stroop test, a word representing a color name is presented colored with a different color, and the subject is asked to name the colored word. The time taken from presentation to the ability to name the colored word is measured. Based on the results of a Stroop test containing a certain number of questions (for example, two sets of 10 questions), such as reaction time and accuracy, the response level of the Stroop test can be determined.

[0021] In this invention, the suppression of increased parasympathetic nervous system activity during nap by geranyl acetate means that, compared to before nap, there is no increase (increase) in parasympathetic nervous system activity during nap, or that it is significantly suppressed. Increased parasympathetic nervous system activity during nap leads to a parasympathetic dominant state, which tends to result in decreased activity after nap. Therefore, in order to improve activity performance after nap, it is preferable to suppress increased parasympathetic nervous system activity during nap. In this invention, the suppression of increased parasympathetic nervous system activity during nap by geranyl acetate can be indicated, for example, by the fact that when geranyl acetate is applied during nap, no increase in pNN50(%) during nap compared to before nap is observed, or the level of increase in pNN50(%) during nap compared to before nap is smaller than the level of increase in pNN50(%) after nap compared to before nap when no fragrance component is applied during nap.

[0022] The composition according to the present invention contains geranyl acetate as an active ingredient, and may contain an effective amount of geranyl acetate. The composition according to the present invention preferably contains geranyl acetate as a fragrance component, and is particularly preferably contained in a volatile state. The composition according to the present invention may be for improving sleep during naps as described above. The composition according to the present invention may also be for at least one selected from the group consisting of promoting increased vitality after napping, promoting reduced drowsiness, promoting recovery from fatigue, and suppressing increased parasympathetic nerve activity during napping.

[0023] In one embodiment, the composition according to the present invention may contain an essential oil, and may contain an essential oil containing geranyl acetate. In one embodiment, the composition according to the present invention may not contain an essential oil, for example, an essential oil containing geranyl acetate. In one embodiment, the composition according to the present invention may contain only geranyl acetate as a fragrance component. In one embodiment, the composition according to the present invention may be a stock solution of geranyl acetate. In one embodiment, the composition according to the present invention may not contain any essential oil-derived fragrance components other than geranyl acetate. In one embodiment, the composition according to the present invention may further contain other synthetic fragrance components.

[0024] The composition according to the present invention may contain other components in addition to geranyl acetate. The composition according to the present invention may contain any additives that can be used in cosmetics, quasi-drugs, etc., such as carriers (e.g., starch, dextrin, resins, fine particles such as liposomes, nonwoven fabrics, porous materials, etc.), aqueous media (water, buffer solutions, etc.), oily media (petrolatum, etc.), surfactants, suspending agents, water-soluble polymers (hydroxypropyl cellulose, etc.), gelling agents, diluents, humectants, excipients, thickeners, pH adjusters, antioxidants, UV absorbers, preservatives, cleaning agents, deodorants, colorants, odor-correcting agents, propellants, etc. The composition according to the present invention may also contain other physiologically active components.

[0025] The composition according to the present invention may be in any form, such as powder, beads, liquid, gel, cream, capsule, sheet, spray, etc. The composition according to the present invention may be a fragrance composition, for example, a sustained-release fragrance composition. The composition according to the present invention may be any product, such as cosmetics, fragrances (for example, fragrance component-impregnated beads), toiletries, air care products, daily necessities and general merchandise, oral compositions, hair care products, skin care products, body care products, laundry detergents, fabric softeners, tobacco products, quasi-drugs, and pharmaceuticals. Preferably, the composition according to the present invention is a product capable of releasing or sustainably releasing fragrance components.

[0026] The composition according to the present invention may be for inhalation of geranyl acetate, particularly for nasal inhalation, allowing the subject to inhale geranyl acetate as a fragrance component. The composition according to the present invention may be for nasal inhalation of geranyl acetate (allowing the subject to inhale geranyl acetate as a fragrance component) during a nap.

[0027] The present invention also provides a method for improving sleep during a nap, which includes applying geranyl acetate to a subject during a nap. The method for improving sleep during a nap according to the present invention can preferably result in at least one selected from the group consisting of promoting increased vitality after the nap, promoting reduced drowsiness, promoting recovery from fatigue, and suppressing increased parasympathetic nervous system activity during the nap. In the method for improving sleep during a nap according to the present invention, it is preferable to have the subject inhale geranyl acetate during the nap, particularly through nasal inhalation (making the subject smell geranyl acetate as an aromatic component). In the method for improving sleep during a nap according to the present invention, nasal inhalation of geranyl acetate may be performed on the subject during the nap using the composition of the present invention containing the geranyl acetate described above. The method for improving sleep during a nap according to the present invention may not involve any medical procedure such as one performed by a physician.

[0028] The application of geranyl acetate to subjects during nap time may be continuous throughout the nap, intermittently, or only for a certain period during the nap. The application of geranyl acetate to subjects during nap time may be performed before the start of the nap or continue after the end of the nap. The effects of the method for improving sleep during nap time according to the present invention, including improved sleep during nap time, promotion of increased vitality after nap, promotion of reduced drowsiness, promotion of fatigue recovery, and suppression of increased parasympathetic nerve activity during nap time, are as described above. The method for improving sleep during nap time according to the present invention can improve at least one of the above-mentioned indicators showing increased vitality after nap, reduced drowsiness, fatigue recovery, and increased parasympathetic nerve activity during nap time.

[0029] In this invention, the "subjects" to whom geranyl acetate is applied during naps may be any person, but for example, they may be people who need naps or who are engaged in activities that involve naps (such as night work). The "subjects" to whom geranyl acetate is applied during naps may also be people who are not being treated for sleep disorders.

[0030] The present invention also provides a method for improving the sleep environment during napping in a living space, which includes releasing geranyl acetate into the living space. The living space from which geranyl acetate is released may be a living space that is currently used or is intended to be used for napping. In the present invention, "living space" refers to an indoor space in which a person stays for a certain period of time, and includes, but is not limited to, bedrooms, studies, living rooms, study rooms, self-study rooms, offices, reception rooms, conference rooms, medical rooms, health rooms, nap rooms, on-call rooms, security guard rooms, rest rooms, tents, etc.

[0031] The release of geranyl acetate into a living space is preferably carried out in such a way that the geranyl acetate is present in the air of the living space for at least a certain period of time, so that the person taking a nap in the living space can inhale the geranyl acetate as a fragrance component through their nose while napping. For example, a fragrance generator may be installed near a napping bed, seat (chair), sofa, tatami mat, or futon placed in the living space, and geranyl acetate may be released from there as a fragrance component. In one embodiment, a fragrance outlet from the fragrance generator may be attached to the inner surface of a hood that covers the head of a napping bed, seat (chair), etc., or to the inside of a curtain installed around it. In another embodiment, geranyl acetate may be released as a fragrance component from the walls, ceiling, floor, or storage area of ​​the living space. The release of geranyl acetate into a living space may be a single release during one nap, an intermittent release, or a sustained release. The release of geranyl acetate into the living space may be initiated automatically by a mechanical mechanism when a nap is taken in the living space, or it may be initiated by a release operation performed by the person taking the nap. The release of geranyl acetate into the living space may also be carried out using a composition containing the geranyl acetate of the present invention.

[0032] The release of geranyl acetate into a living space can improve the sleep environment during naps. "Improving the sleep environment during naps in a living space" means, as described above, providing a sleep environment in which the sleep of the subject during naps in that living space is improved by geranyl acetate, leading to improved activity performance after the nap. Improving the sleep environment during naps in a living space by releasing geranyl acetate into the living space can create a sleep environment that can produce at least one of the following effects selected from the group consisting of promoting increased vitality after naps, promoting reduced drowsiness, promoting fatigue recovery, and suppressing the enhancement of parasympathetic nervous system activity during naps. [Examples]

[0033] The present invention will be described in more detail below using examples. However, the technical scope of the present invention is not limited to these examples.

[0034] Participants were exposed to fragrance components and then asked to take a nap, and the effects of the fragrance components on sleep were evaluated.

[0035] Thirty-seven subjects (men and women aged 10 to 50) participated in the evaluation test. Each subject underwent an evaluation test that included a nap, completion of questionnaires before and after the nap, fatigue level measurement, and electrocardiogram measurement, for approximately one hour between 2 PM and 5 PM.

[0036] For each subject's nap area, an executive lounge seat derived from an automobile (Alphard, Toyota Motor Corporation) was used, and a foldable hood that could cover the subject's head was installed on the seat to adjust the brightness and provide a sense of psychological security (Figures 1A and 1B).

[0037] The inner surface of the foldable hood was positioned to serve as a fragrance outlet, with the open end of a tube extending from a fragrance generator containing fragrance-impregnated beads positioned there to provide fragrance to subjects during nap time.

[0038] Table 1 shows the fragrance components and fragrance delivery conditions used in the evaluation test. Each subject underwent the evaluation test under each of the conditions No. A to C.

[0039] [Table 1]

[0040] The evaluation test was conducted according to the test protocol shown in Figure 2, and the changes in fatigue and alertness before and after napping were assessed. First, subjects completed a questionnaire (questionnaire survey) and had their fatigue levels measured. Next, subjects sat in an executive lounge seat as shown in Figure 1A and rested with their eyes open for 3 minutes. Then, as shown in Figure 1B, they reclined the executive lounge seat, covered their heads with the hood, and took a 20-minute nap. Finally, they sat in the upright executive lounge seat and rested with their eyes open for 3 minutes. Electrocardiogram measurements were continuously taken during the resting period with eyes open before and after napping, and during the nap itself. Finally, subjects completed another questionnaire and had their fatigue levels measured again, concluding the approximately one-hour evaluation test.

[0041] The investigations, measurements, and data analyses in the test protocol were carried out as follows:

[0042] 1) Questionnaire survey Each participant completed a questionnaire using the RAS (Roken Arousal Scale; subjective fatigue and arousal assessment index) (a subjective assessment index developed under the Industrial Science and Technology Research and Development Project "Human Sensory Measurement Application Technology"; from the Human Sensory Database for Workplace Environment Diagnosis, Human Life Engineering Research Center) before and after their nap, as shown in Figure 2. The RAS questions are shown in Table 2.

[0043] [Table 2]

[0044] Each question item in the RAS corresponds to one of the six sensory scales shown in Table 3, with two questions belonging to each sensory scale.

[0045] [Table 3]

[0046] For each question item, a rating scale of 1 to 7 points was assigned, with 1 point for "does not apply," 3 points for "somewhat applies," 5 points for "strongly apply," and 7 points for "very much applies." The rating for each sensory scale for each subject was calculated by averaging the two questions belonging to each sensory scale.

[0047] Furthermore, the change in the rating values ​​for each sensory scale before and after the nap was calculated (ΔRating value = Rating value after nap - Rating value before nap).

[0048] The Δ rating values ​​for each sensory scale were compared and examined for each subject and for each fragrance component, and Steel-Dwass multiple comparison tests were performed to determine whether there were any statistically significant differences.

[0049] The results of this RAS questionnaire survey showed that the fragrance component geranyl acetate has the effect of increasing overall activity after napping (Figure 3) and reducing drowsiness (Figure 4).

[0050] 2) Electrocardiogram measurement Slimee contact biosensor attached to the subject's chest. TM The Bar Type Lite (TDK) was attached, and as shown in Figure 2, vital signs were measured before and after napping, during eye-open rest, and during napping.

[0051] The average values ​​of measurement data for 3 minutes before and after napping, when the eyes were open and at rest, were calculated. Additionally, the 20-minute nap was divided into four 5-minute stages, and the average value of measurement data for 3 minutes, excluding the first and last minutes of each stage, was calculated. The change in measurement value (Δ) was calculated by subtracting the average value of the 3-minute measurement data during the pre-nap, eye-open, and resting period from the average value of the 3-minute measurement data during the nap, and this was compared between different fragrance provision conditions.

[0052] The results showed that geranyl acetate has the effect of reducing ΔpNN50(%) during nap time (Figure 5). pNN50(%) is the percentage of heartbeats in which the difference between adjacent normal RR intervals (RR interval; RRI) exceeds 50 ms, and is an indicator of parasympathetic nervous system activity. This result indicates that geranyl acetate acts on the autonomic nervous system and suppresses the increase in parasympathetic nervous system activity during nap time.

[0053] 3) Fatigue level measurement For each subject, flicker values ​​were measured and fatigue levels were assessed based on the Stroop test before and after the nap, as shown in Figure 2.

[0054] Flicker value measurement identifies the frequency threshold at which a subject can no longer perceive the flashing light ("flicker"), based on the fact that humans have difficulty visually perceiving high-frequency light flashes. Flicker value measurement is widely used in the fields of ergonomics and occupational health as a test for mental fatigue. A low flicker value (Hz) indicates a high level of fatigue, while a high flicker value indicates a low level of fatigue. Changes (decreases) in flicker value associated with fatigue are thought to represent a decrease in the temporal resolution of the visual system and reflect a decline in the function of the cerebral cortex.

[0055] Flicker values ​​were measured for each subject before and after naps using a Type II (automatic) flicker value measuring device (TKK-501C, Takei Kiki Kogyo). The flashing speed (frequency) was gradually increased, and the frequency (Hz) at which the subject could no longer perceive "flickering" was defined as the flicker value. Three measurements were taken for each subject, and the average value was calculated. Next, the flicker values ​​before and after naps were compared for each subject, and the percentage of subjects whose flicker values ​​improved (increased) after naps compared to before naps (number of subjects whose flicker values ​​improved after naps / total number of subjects × 100 (%)) was calculated.

[0056] The results showed that geranyl acetate has a significant effect in improving flicker levels after napping (Figure 6A). This indicates that geranyl acetate promotes improvements in mental fatigue and visual fatigue through napping.

[0057] The Stroop test was conducted using a Stroop test app called EncephalApp-Stroop Test Jasmohan Bajaj. Before and after a nap, subjects were presented with color names such as "red," "blue," and "green," colored differently from their original colors, and asked to call out the colored words (for example, the word "green" written in red, now colored red). This Stroop test is based on the Stroop effect, where presenting a color name with a different color interferes with the ability to smoothly call out the colored words. The Stroop test is a test used to measure the attention and interference inhibition functions of the frontal lobe and is used to evaluate the brain's attentional function. Specifically, two sets of 10 questions each were measured, and the total time taken for the two sets (total reaction time) was calculated. Next, the total reaction time of the Stroop test before and after the nap was compared for each subject, and the percentage of subjects whose total reaction time improved (decreased) after the nap compared to before the nap was calculated (number of subjects whose total reaction time improved after the nap / total number of subjects × 100 (%)).

[0058] The results showed that geranyl acetate significantly improved the total reaction time on the Stroop test after napping (Figure 6B). This indicates that geranyl acetate promotes improvement in mental fatigue and attention function through napping.

[0059] These results indicate that geranyl acetate has a significant fatigue-recovering effect after napping.

Claims

1. A composition for improving sleep during naps, containing geranyl acetate as an active ingredient.

2. The composition according to claim 1, which is a fragrance composition.

3. The composition according to claim 1 for at least one selected from the group consisting of promoting increased vitality after napping, promoting reduced drowsiness, promoting recovery from fatigue, and suppressing increased parasympathetic nerve activity during napping.

4. A method for improving sleep during a nap, which includes administering geranyl acetate via nasal inhalation to a subject during a nap, A method for producing at least one selected from the group consisting of promoting increased vitality after napping, promoting reduced drowsiness, promoting recovery from fatigue, and suppressing increased parasympathetic nervous system activity during napping.

5. A method for improving the sleep environment during naps in a living space, including the release of geranyl acetate into the living space.

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