A low-irritation soothing composition and uses thereof

Abstract

This invention relates to a low-irritation soothing composition and its application, belonging to the technical field of skin care products. The low-irritation soothing composition, by weight percentage, comprises 0.05–0.2 wt% kava soothing agent, 0.3–1.0 wt% pine nut extract, 1.8–2.5 wt% a mixed emulsifier composed of cetearyl alcohol and glyceryl stearate, wherein the mass ratio of cetearyl alcohol to glyceryl stearate is 2.5–3.5:1; 2.0–5.0 wt% moisturizer, 0.4–1.0 wt% preservative, 0–2.0 wt% cosmetically acceptable excipients, and the balance being water. This invention utilizes the synergistic effect of low concentrations of kava soothing agent and pine nut extract, and employs a low total fat emulsification system to form a delicate and stable O / W emulsion, reducing transepidermal water loss and repairing the physical barrier; together, they maintain a low-inflammatory, low-oxidative, and microbial balanced microenvironment, providing ideal conditions for barrier repair.

Description

Technical Field

[0001] This invention belongs to the technical field of skin care products, and more specifically, relates to a low-irritation soothing composition and its application. Background Technology

[0002] With the widespread use of phototherapy-based cosmetic procedures such as fractional laser, microneedling, and radiofrequency ablation, postoperative acute skin barrier damage has become a common clinical problem. These treatments induce collagen regeneration through controlled thermal damage or physical puncture, but simultaneously lead to damage to the stratum corneum structure, a sharp increase in transepidermal water loss (TEWL) (often 3–5 times higher than pre-treatment levels), and activation of sensory nerve endings and immune cells, triggering acute inflammatory reactions such as burning, stinging, and redness. If not properly repaired, this can easily develop into chronic sensitivity, pigmentation, or even barrier dysfunction.

[0003] Currently, commercially available post-operative repair products mainly rely on the following strategies:

[0004] (1) Single plant-based soothing ingredients, such as asiaticoside, purslane extract, bisabolol, etc., have certain anti-inflammatory effects, but they take effect slowly and usually require more than 24 hours, making it difficult to cope with acute symptoms within 0–72 hours after surgery.

[0005] (2) Adding traditional cooling agents such as menthol and camphor can quickly relieve the burning sensation, but they are irritating and may aggravate the nerve sensitization of fragile skin after surgery. They are especially unsuitable for people with rosacea or highly sensitive skin.

[0006] (3) High concentration of active ingredients are combined, such as simply stacking multiple anti-inflammatory extracts. Although the intention is to enhance the efficacy, the stability or irritation often decreases due to osmotic competition, component interaction or lipid system overload.

[0007] Most importantly, current technologies generally overlook the crucial impact of emulsification systems on the performance of post-operative products. While high lipid content can enhance moisturizing properties, it can hinder the transdermal release of active ingredients and delay the onset of soothing effects; on the other hand, low-lipid formulas often face issues such as physical instability and a rough texture. Finding a balance between gentleness, stability, and efficacy remains a key technical challenge for the industry.

[0008] In summary, there is an urgent need for an innovative composition that can quickly soothe neuroinflammation, effectively rebuild the physical barrier, and has extremely low irritation, making it suitable for the acute phase after medical aesthetic procedures. Summary of the Invention

[0009] The purpose of this invention is to provide a low-irritation soothing composition and its application. Based on in-depth research on the mechanism of action of kava soothing agent and pine berry extract, the inventors unexpectedly discovered that they can produce a significant synergistic effect under specific ratios and formulation conditions. When used within 0-72 hours after medical aesthetic procedures, it has the characteristic of rapidly reducing transdermal water loss rate.

[0010] The objective of this invention can be achieved through the following technical solutions:

[0011] A low-irritant soothing composition comprising, by weight percentage:

[0012] 0.05–0.2 wt% Kava Soothing Agent;

[0013] 0.3–1.0 wt% Pineberry Extract;

[0014] 1.8–2.5 wt% of a mixed emulsifier consisting of cetearyl alcohol and glyceryl stearate, wherein the mass ratio of cetearyl alcohol to glyceryl stearate is 2.5–3.5:1;

[0015] 2.0–5.0 wt% humectant;

[0016] 0.4-1.0wt% preservative;

[0017] 0-2.0 wt% cosmetic-acceptable excipients; and

[0018] The remainder is water.

[0019] The low-irritation soothing composition of the present invention contains kava soothing agent and manuka extract. Kava soothing agent is derived from kava pepper, and its main active ingredient is kava lactone. Manuka extract refers to the New Zealand endemic plant Manuka tree, and its main active ingredients are triterpenoids, polyphenols, flavonoids, and tannins.

[0020] The kava sedative and pine berry extract produce a significant synergistic effect through a multi-level molecular mechanism: on the one hand, the kava lactones in kava sedative can effectively inhibit the activity of TRPV1 / TRPA1 channels on skin sensory neurons and downregulate the NF-κB signaling pathway, thereby rapidly blocking the burning sensation, stinging, and release of acute inflammatory factors caused by medical aesthetic stimulation; on the other hand, pine berry extract is rich in triterpenoids and polyphenols, which can significantly upregulate the expression of tight junction proteins claudin-1 and filaggrin in keratinocytes, promote the reconstruction of the integrity of the stratum corneum structure, and maintain the homeostasis of the local microenvironment by scavenging reactive oxygen species.

[0021] Most importantly, the inhibitory effect of kavastatin on inflammatory factors can prevent the negative regulation of claudin-1 and filaggrin expression by factors such as IL-1α and TNF-α, thus providing favorable conditions for the barrier repair function of pine berry extract. Furthermore, the inhibition of mast cell degranulation and oxidative stress by pine berry extract can also reduce secondary sensitization of nerve endings and prolong the sedative effect of kavastatin. These two factors form a positive feedback loop at the neuro-immune-barrier three-dimensional level, achieving a technical effect that combines immediate sedation with long-term barrier reconstruction.

[0022] Furthermore, the composition is an O / W type emulsion with a pH value of 5.2–5.8.

[0023] Furthermore, this invention employs a specific ratio of cetearyl alcohol and glyceryl stearate to construct a low-fat O / W emulsion system, which ensures the physical stability of the formulation while avoiding high lipid content that hinders the transdermal release of active ingredients, thus balancing gentleness and efficacy.

[0024] Among them, Kava Soothing Agent is a Kava Pepper root extract. The total content of Kava lactone compounds in Kava Soothing Agent is at least 60 wt%, and the total content of pyranone impurities is less than 0.1 wt%.

[0025] Specifically, the pyranone impurities mentioned in this article refer to non-kava lactone pyranone derivatives produced during the extraction of pepper root, mainly including flavokavain A, flavokavain B, and flavokavain C.

[0026] Furthermore, the pine pine extract is a water-ethanol extract, wherein the content of triterpenoid compounds is at least 8 wt%.

[0027] Specifically, the triterpenoids in Prunus cerasifera are leptospermone, flamesone, and isodeoxyflavesone.

[0028] Furthermore, the moisturizer is selected from at least one of glycerin, panthenol, and sodium hyaluronate.

[0029] More preferably, the moisturizer is a composite moisturizing system composed of glycerin, panthenol, and sodium hyaluronate, wherein the mass ratio of glycerin, panthenol, and sodium hyaluronate in the composite moisturizing system is 50-60:9-10:1.

[0030] More preferably, the glycerin, panthenol and sodium hyaluronate constituting the composite moisturizing system are present in the composition in the following mass percentages: 3 wt%, 0.5 wt%, and 0.05 wt%, respectively.

[0031] Furthermore, the molecular weight of the sodium hyaluronate is 50–500 kDa.

[0032] Within this range, sodium hyaluronate provides adequate hydration without hindering the transdermal release of kava soothing agent and pine berry extract, thus synergistically achieving low irritation and high-efficiency repair.

[0033] Furthermore, the preservative is selected from at least one of phenoxyethanol, ethylhexylglycerin, octyl glycol, and pentanediol.

[0034] Preferably, the preservative is a composite preservative composed of octyl glycol and pentylene glycol, wherein the mass ratio of octyl glycol to pentylene glycol in the composite preservative is 1:1 to 3:2.

[0035] Furthermore, the pH of the composition is adjusted to 5.2–5.8 by lactic acid and / or arginine.

[0036] The pH of healthy human skin is 4.5–5.9. This slightly acidic environment helps maintain barrier function, inhibit harmful bacteria, and activate lipid synthesis enzymes. After cosmetic procedures, the skin's pH may temporarily rise above 6.5; timely restoration of this slightly acidic environment can accelerate barrier repair. Lactic acid has moisturizing, gentle exfoliating, and antibacterial properties and is widely used in cosmetics due to its high safety profile. Arginine has extremely low irritation and moisturizing and anti-inflammatory effects. When combined with lactic acid, it forms a buffer system to stabilize pH and can synergistically enhance the effects of amino acids in pine needles.

[0037] Furthermore, the cosmetic excipients acceptable to the product include at least one of chelating agents, antioxidants, or fragrances. These excipients do not affect the core efficacy of the invention and are primarily used to improve product stability or user experience.

[0038] The preparation method of the above-mentioned low-irritation soothing composition includes the following steps:

[0039] S1. Melt cetearyl alcohol and glyceryl stearate at 70–80°C to obtain the oil phase;

[0040] S2. Heat water and humectant to 70–80°C to obtain an aqueous phase;

[0041] S3. While stirring, continuously add the oil phase to the aqueous phase and homogenize for 5–10 minutes;

[0042] S4. Cool to 40–45℃, add kava soothing agent and pine berry extract, continue stirring to 30–35℃, add preservatives, and adjust the pH to 5.2–5.8 with lactic acid and / or arginine to obtain the finished product.

[0043] Furthermore, in step S3, the rotational speed of the homogenizer is 8000-12000 rpm.

[0044] The use of the aforementioned low-irritant soothing compositions in the preparation of skin care products or topical formulations for repairing acute damage to the skin barrier.

[0045] The skin care products or topical preparations mentioned herein, when used within 72 hours of acute damage to the skin barrier, can effectively reduce transepidermal water loss.

[0046] The beneficial effects of this invention are:

[0047] (1) This invention reduces the sensitivity of nerve endings to heat, acid, and inflammatory mediators by inhibiting the activity of TRPV1 and TRPA1 channels through low concentrations of kavastatin, thereby reducing the release of pro-inflammatory factors such as IL-6 and TNF-α, and thus achieving rapid relief of stinging, burning, and sudden redness. Meanwhile, the extract of pine berries enhances the "sealing" between stratum corneum cells by increasing the expression of claudin-1 and occludin, thereby maintaining stratum corneum hydration, promoting the dual reconstruction of "lipid-protein", reducing transepidermal water loss, and repairing the physical barrier; together, they maintain a low-inflammatory, low-oxidative, and microbial-balanced microenvironment, providing ideal conditions for barrier repair.

[0048] (2) The present invention uses a low total fat emulsification system to form a delicate and stable O / W emulsion with no greasy feeling. The obtained composition can effectively reduce the transepidermal water loss rate of the skin when used within 72 hours after laser or microneedling, which is far superior to single ingredients or conventional ratio combinations. Detailed Implementation

[0049] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0050] In this embodiment of the invention, the total content of kavalactone was 62.3% and the content of pyranone impurities was 0.03% as determined by HPLC; the content of triterpenoids in the pine berry extract was 9.6%, provided in the form of 30% ethanol aqueous solution.

[0051] Example 1

[0052] A low-irritant soothing composition comprising, by weight percentage:

[0053] Kava Soothing Agent 0.15wt%, Prunus cerasifera Extract 0.7wt%, Cetearyl Alcohol 1.8wt%, Glyceryl Stearate 0.6wt%, Glycerin 3.0wt%, Panthenol 0.5wt%, Sodium Hyaluronate (Molecular Weight 50kDa) 0.05wt%, Disodium EDTA 0.05wt%, Caprylyl Glycol 0.4wt%, Pentylene Glycol 0.3wt%, and Deionized Water to make up to 100wt%.

[0054] The preparation method of the above-mentioned low-irritant soothing composition is as follows:

[0055] S1. Cetearyl alcohol and glyceryl stearate are heated to 75±2℃ to melt, and the oil phase is obtained.

[0056] S2. Water, glycerin, sodium hyaluronate, panthenol, and disodium EDTA are heated to 75±2℃ to obtain an aqueous phase.

[0057] S3. Slowly add the aqueous phase to the oil phase while stirring, and homogenize at 8000 rpm for 5–10 minutes.

[0058] S4. Cool to 45℃, add kava soothing agent and pine berry extract, continue stirring to 35℃, add preservative, stir evenly, adjust pH to 5.5 with 10wt% lactic acid aqueous solution and 10wt% arginine aqueous solution to obtain the finished product.

[0059] Example 2

[0060] A low-irritant soothing composition comprising, by weight percentage:

[0061] Kava Soothing Agent 0.05wt%, Pineberry Extract 1.0wt%, Cetearyl Alcohol 1.8wt%, Glyceryl Stearate 0.6wt%, Glycerin 3.0wt%, Panthenol 0.5wt%, Sodium Hyaluronate (Molecular Weight 50kDa) 0.05wt%, Disodium EDTA 0.05wt%, Phenoxyethanol 0.2wt%, Ethylhexylglycerin 0.2wt%, and deionized water to make up to 100wt%.

[0062] The preparation method of the above-mentioned low-irritant soothing composition is the same as that in Example 1.

[0063] Example 3

[0064] A low-irritant soothing composition comprising, by weight percentage:

[0065] Kava Soothing Agent 0.2wt%, Pine Blossom Extract 0.3wt%, Cetearyl Alcohol 1.8wt%, Glyceryl Stearate 0.6wt%, Glycerin 3.0wt%, Panthenol 0.5wt%, Sodium Hyaluronate (Molecular Weight 50kDa) 0.05wt%, Disodium EDTA 0.05wt%, Caprylyl Glycol 0.6wt%, Pentylene Glycol 0.4wt%, and Deionized Water to make up to 100wt%.

[0066] The preparation method of the above-mentioned low-irritant soothing composition is the same as that in Example 1.

[0067] Comparative Example 1

[0068] Compared with Example 1, the difference in this comparative example is that the mass percentage of kava soothing agent and the mass percentage of pine berry extract in this comparative example are 1.0 wt%, while the other components, preparation steps and parameters are the same.

[0069] Comparative Example 2

[0070] Compared with Example 1, this comparative example differs in that it contains only 0.15 wt% kava soothing agent and does not contain pine berry extract, while the other components, preparation steps and parameters are the same.

[0071] Comparative Example 3

[0072] Compared with Example 1, this comparative example differs in that it contains only 0.7 wt% of pine syrup extract and does not contain kava soothing agent, while the other components, preparation steps and parameters are the same.

[0073] Comparative Example 4

[0074] Compared with Example 1, this comparative example differs in that the mass percentage of cetearyl alcohol is 2.5 wt% and the mass percentage of glyceryl stearate is 2.5 wt%, while the remaining components, preparation steps and parameters are the same.

[0075] Specific experimental design and detection indicators:

[0076] Experiment 1: Verification of the barrier's ability to repair acute damage

[0077] Methods: Forty-eight male ICR (CD-1) mice weighing 25–30 g were randomly divided into 8 groups of 6 mice each. Hair was removed from the backs of the mice, and the skin was allowed to heal for 24 hours. Then, 3MScotch® Magic was applied. TMStandard adhesive tape was applied vertically to the same area and then quickly peeled off 15 times to establish an acute barrier injury model. Symmetrical areas (approximately 2×2cm on each side) were selected on both sides of each mouse as treatment areas. Transdermal water loss rate (TEWL) was measured immediately after the tape was removed. Only mice with TEWL ≥ 3 times the baseline value (baseline: measured 24h after hair removal) were included in the experiment.

[0078] Dosage regimen: 0 h after tape removal, mice in groups 1-3 were smeared with samples from Examples 1-3, mice in groups 4-7 were smeared with samples from Comparative Examples 1-4, and mice in group 8 were smeared with a blank matrix sample containing only the matrix and excluding kava sedative and pine berry extract. Each group was smeared with 20 μL / cm³ of the corresponding sample. 2 Take it once in the morning and once in the evening for three consecutive days.

[0079] Testing method: Tests were conducted before tape peeling (baseline) and at 0h, 24h, 48h, and 72h after peeling.

[0080] ① Transdermal water loss rate (TEWL) in mice, measured using a Tewameter®™ 300 instrument; unit: g / m 2 / h; ②Covering moisture content, measured by Corneometer® CM825, unit: AU.

[0081] Calculate TEWL recovery rate = [(TEWL 0h –TEWL t ) / (TEWL 0h –TEWL 基线 )]×100%.

[0082] Each mouse was measured three times at each time point, and the average value was taken.

[0083] 72 hours after the last administration, the mice were euthanized, and the skin of the treated area on the back (0.5×0.5cm) was taken and fixed with 4% paraformaldehyde, embedded in paraffin, sectioned at 5μm, and stained with hematoxylin and eosin (HE) to observe the epidermal thickness, stratum corneum integrity, and inflammatory cell infiltration.

[0084] The integrity of the stratum corneum was scored from 0 to 2: 0 = peeling / fragmentation, 1 = partial loss, 2 = continuous and intact; inflammatory cell infiltration: count the number of inflammatory cells in the superficial dermis per high power field (×400) ( / HPF); epidermal thickness: measure the vertical distance (μm) from the basal layer to the top of the stratum corneum.

[0085] The test results are shown in Table 1.

[0086] Table 1

[0087]

[0088] Among them, *p<0.05 vs blank control; ***p<0.01 vs other comparative examples and single-use groups.

[0089] As shown in Table 1, groups 1-3 (Examples 1-3) exhibited higher TEWL recovery rates and stratum corneum moisture content after 72 hours, indicating that the composition of this invention can achieve rapid hydration within 72 hours after acute skin barrier damage. Furthermore, groups 1-3 showed higher stratum corneum integrity scores, lower inflammatory cell counts, and higher epidermal thickness values, demonstrating that the composition of this invention can rapidly repair the skin after skin barrier damage. Group 4 (Comparative Example 1) had excessively high levels of kava soothing agent and pine berry extract. While it had some hydrating effect, the number of inflammatory cells was significantly higher than in groups 1-3, indicating that high concentrations of active ingredients can easily cause local irritation and affect the repair effect. Group 5 (Comparative Example 2) lacked pine berry extract, and Group 6 (Comparative Example 3) lacked kava soothing agent. Both TEWL recovery and skin barrier recovery effects decreased, indicating that kava soothing agent and pine berry extract have a significant synergistic effect in barrier repair. Group 7 (Comparative Example 4) may have experienced decreased repair efficiency due to lipid overload, which could hinder the release of active ingredients. Group 8 (blank matrix group) experienced an aggravated inflammatory response due to the lack of active substances.

[0090] Experiment 2: TEWL and Barrier Repair Effects After Human Medical Aesthetics

[0091] Methods: Twenty volunteers aged 25-45 years who underwent fractional laser treatment on their face were recruited. Post-treatment, the face was divided into five test zones (left / right forehead, left / right cheek, and jaw): zones A, B, C, D, and E. A randomized Latin square design was used. At 0h, 6h, 12h, 24h, 48h, and 72h post-treatment, zone A used the sample from Example 1, zone B used the sample from Comparative Example 1, zone C used the sample from Comparative Example 2, zone D used the sample from Comparative Example 3, and zone E used the sample from Comparative Example 4. The dosage was 2.0 mg / cm². 2 .

[0092] TEWL measurement: preoperative (baseline), postoperative 0h, 24h, 48h, 72h, each region was repeated 3 times and the average value was taken.

[0093] The test results are shown in Table 2.

[0094] Table 2

[0095]

[0096] As shown in Table 2, in the human model after fractional laser surgery, region A (Example 1) achieved a significant reduction in TEWL within 72 hours, which was better than regions B, C, D, and E. This indicates that the low concentration of active ingredient ratio is more effective and gentler than the high concentration of active ingredient in region B (Comparative Example 1). The combined effect of two active ingredients is more effective than the single active ingredient in regions C and D (Comparative Examples 2 and 3). The optimized emulsification system is more conducive to barrier repair than the high-fat formula in region E (Comparative Example 4).

[0097] In summary, by limiting the low concentration window of active ingredients and optimizing the emulsifier ratio, this invention can accelerate TEWL recovery, improve skin hydration levels, maintain the integrity of the stratum corneum, and inhibit inflammatory responses, thereby promoting barrier repair while reducing the risk of irritation.

[0098] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A low-irritation soothing composition, characterized in that, By mass percentage, it includes the following components: 0.05-0.2wt% Kava Pepper Root Extract; 0.3-1.0wt% Pineberry Extract; 1.8-2.5 wt% of a mixed emulsifier composed of cetearyl alcohol and glyceryl stearate, wherein the mass ratio of cetearyl alcohol to glyceryl stearate is 2.5-3.5:1; 2.0-5.0wt% humectant; 0.4-1.0wt% preservative; 0-2.0 wt% cosmetic-acceptable excipients; and The remainder is water; The composition is an O / W type emulsion with a pH value of 5.2-5.8; The total content of kavalactone compounds in the kava pepper root extract is at least 60 wt%, and the total content of pyranone impurities is less than 0.1 wt%; the pine berry extract is a water-ethanol extract, wherein the content of triterpenoid compounds is at least 8 wt%. The moisturizer is a composite moisturizing system composed of glycerin, panthenol and sodium hyaluronate, and the mass ratio of glycerin, panthenol and sodium hyaluronate in the composite moisturizing system is 50-60:9-10:

1. The molecular weight of the sodium hyaluronate is 50-500 kDa; The cosmetic excipients acceptable to the cosmetic are at least one of chelating agents, antioxidants, or fragrances.

2. The low-irritation soothing composition according to claim 1, characterized in that, The pH of the composition is adjusted to 5.2-5.8 by lactic acid and / or arginine.

3. The low-irritation soothing composition according to claim 1, characterized in that, The preservative is selected from at least one of phenoxyethanol, ethylhexylglycerin, octyl glycol, and pentylene glycol.

4. The low-irritation soothing composition according to claim 3, characterized in that, The preservative is a composite preservative composed of octyl glycol and pentylene glycol, wherein the mass ratio of octyl glycol to pentylene glycol in the composite preservative is 1:1-3:

2.

5. Use of the low-irritant soothing composition according to any one of claims 1-4 in the preparation of cosmetics for repairing acute damage to the skin barrier.

6. Use of the low-irritant soothing composition according to any one of claims 1-4 in the preparation of a topical formulation for repairing acute damage to the skin barrier.

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