Iris extract for hair care

Abstract

The present invention relates to the use of an Iris rhizome extract and a composition containing said Iris rhizome extract in the field of cosmetics for limiting hair loss and / or promoting hair growth.

Description

Technical Field

[0001] This invention relates to at least one species belonging to the iris family ( Iris Rhizome extracts from species of the genus Iris and those containing these Iris species ( Iris spp. The composition of one of the extracts is used in the cosmetics field, particularly in the hair care field, for the purpose of limiting hair and / or body hair loss and / or promoting hair and / or body hair growth. Background Technology

[0002] Hair care has always been a subject of research, not only for cosmetic purposes, but also for preventing hair loss and promoting hair regrowth. Many theories attempt to elucidate the etiology of hair loss in conditions such as baldness, alopecia areata, and patchy hair loss, attributing it to seborrhea, increased tension in skull tissues, reduced blood flow, or certain endocrine or neurological disorders.

[0003] Hair follicles are tiny organs embedded in the skin and extending into the subcutaneous tissue, whose primary function is to produce hair shafts. Their distribution is determined during intrauterine development, and their number is genetically determined. Hair follicles are dynamic structures that produce hair during the tissue's growth and remodeling cycle. This cycle consists of three phases: - Growth Phase (Early Hair Growth): Cells in the dermal papilla (fibroblasts) send signals to the stem cells of the hair follicle, enabling them to proliferate. These cells transform and envelop the dermal papilla to form the hair matrix. They divide and differentiate into keratinocytes, the cells responsible for hair structure. For hair to have a good structure, these keratinocytes require sulfur-containing proteins, vitamin B6, and various minerals (such as zinc and magnesium). The duration of this phase determines hair length and depends on the proliferation and differentiation of the stromal cells at the base of the hair follicle.

[0004] - Regression phase (mid-hair growth phase): The matrix dies, therefore, the dermal papilla no longer comes into contact with the matrix. There is no longer any exchange between cells. The hair follicle and dermal papilla move upwards towards the epidermis.

[0005] - Resting phase (telogen effluvium): The cells of the dermal papilla and hair follicle remain intact and inactive. Hair falls out. The cycle must be restarted for new hair to grow.

[0006] To date, various products have been developed to combat hair loss, particularly those that induce or stimulate hair growth. Most products combine several active ingredients that may have beneficial effects on the biological factors involved in hair loss. Among the most common active ingredients are, for example: vitamins such as vitamins A, E, B5, B6, C, H, and PP; trace elements such as zinc, copper, magnesium, and silicon; protein derivatives such as peptides and sulfur-containing amino acids (e.g., methionine, cysteine, or their derivatives); essential oils or lipophilic or hydrophilic plant extracts, and so on. This list is not exhaustive.

[0007] Therefore, despite the many options available today, consumers still need new, natural, and environmentally friendly products to promote hair regeneration.

[0008] Iris ( ) Iris Tourn. ex L. (hereinafter referred to as Iris) Iris The plant belongs to the Iridaceae family. Iridaceae The genus *Iris* comprises over 300 species, widely distributed throughout the world, primarily in the Northern Hemisphere, with highly diverse habitats (*Iris Tourn. ex L.* | Plants of the World Online | KewScience, accessible at https: / / powo.science.kew.org / taxon / urn:lsid:ipni.org:names:326330-2). Species of *Iris* are perennial herbaceous plants with rhizomes or bulbs and alternate leaves of varying shapes. Flowers are distichous, linear or sword-shaped, borne on a single or branched stem. The flowers have three outer sepals (usually reflexed) that act as sepals and three smaller, erect inner sepals (petals) (Prof. Pierre Delaveau, 2003, p. 305). Several common iris species exist, such as the Florentine iris (*Iris florida*). Iris florentina L.), Iris tectorum ( Iris pallida Lam., German Iris ( Iris x germanica L.), etc.

[0009] The Florentine iris is a species native to the Arabian Peninsula, now naturalized in several countries in the Mediterranean basin, and is highly valued for its ornamental and aromatic qualities.

[0010] Fragrant Iris is a species native to Italy or the Balkan Peninsula, and has now been naturalized in several countries in the Mediterranean basin and North America. This plant can grow to a height of over 1 meter, with a thick rhizome and broad, sword-shaped leaves (shorter than the stem). Large, fragrant, pale blue flowers grow on short pedicels, with 2 or 3 flowers on each spathe.

[0011] The German iris (sometimes called "Iris d'Allemagne") is a hybrid species believed to originate from the Chinese iris and the Hungarian iris. Iris variegata A hybrid of L. (L.), native to the Mediterranean region, it has now naturalized in many countries around the world. Its pointed, sword-shaped leaves can reach 50 cm in length and 3 to 4 cm in width. Highly prized for its ornamental qualities, it is said to have thousands of varieties.

[0012] The rhizomes of German iris, Florentine iris, and vetiver iris are also valuable in perfumes, especially because of their violet-like fragrance.

[0013] Extracts from species belonging to the genus Iris are also found in several anti-aging beauty and oral care products.

[0014] The main secondary metabolites of Iris species belong to the flavonoid family. These flavonoids are primarily isoflavones (iris flavonoids, iriline, irisin, irisin, irisflavin, etc.), flavanones, dihydroflavonols, and flavonols (usually present in lower amounts). They exist in aglycone or glycosylated forms. Anthocyanins (delphin and its derivatives) are also present in the flowers, while flavonoids (O-glycosylated and C-glycosylated) are mainly found in the leaves and flowers (Iwashina and Mizumo 2020; Wang et al. 2010).

[0015] Certain xanthones have also been reported in species of the genus Iris, such as Iris tectorum or Iris variegata. Iris versicolor Mangiferin or isomangiferin in L.

[0016] Triterpenoids have also been recorded in certain species of the genus Iris. Irisones (γ-iridotone, α-iridotone, and α-ionone...) present in the absinth of certain species (Iris davidiana; Iris floridola; Iris irigermanal) are formed during rhizome aging through the oxidation of bicyclic triterpenoids (i.e., iridals (iripallidal, iriflorentinal, irigermanal, either free or esterified with fatty acids) (Jean Bruneton 2015; Wang et al. 2010).

[0017] Certain parts of certain species in the genus Iris (Iris tectorum) Iris pallasii Fish. ex Trevir.), Iris macrocarpa ( Iris bungei The seeds of Maxim. also contain quinones as minor products (hydroxyiridoquinones) (Hadfield et al. 2020; Rahman et al. 2000).

[0018] Numerous pharmacological studies of extracts from different species of Iris have been described in the literature, demonstrating their neuroprotective, antioxidant, or anthelmintic activities.

[0019] Patent application KR2006-0045694 also discloses an iris extract containing isopallasson C for the treatment of alopecia targeting 5α-reductase. The extract is obtained by extraction with methanol followed by back-extraction with hexane to obtain a chloroform-soluble fraction. No specific species is described; the extract described in the examples is derived from seeds. The active compound in this purified extract is isopallasson C, which inhibits the activity of 5α-reductase. The extract is administered orally or parenterally at doses of isopallasson C ranging from 0.001 mg / kg to 10 mg / kg. Isopropyl ether (3-((Z)-heptadecane-9-enyl)-2-hydroxy-5-methoxycyclohexane-2,5-diene-1,4-dione), with the molecular formula C24H38O4, is a 1,4-benzoquinone with a (Z)-heptadecane-9-enyl chain at the 3-position, a methoxy group at the 5-position, and a hydroxyl group at the 2-position. To the best of our knowledge, the structure of this molecule is not recorded in any other searchable literature in bibliographies, nor in any database of natural molecules of any plant species, such as Natural Products Dictionary, Wikidata, COCONUT (COCONUT: Natural Products Online), or LOTUS (LOTUS: Natural Products Online).

[0020] However, to date, no bibliographical data mentions that Iris rhizome extracts may have activities that limit hair and / or body hair loss and / or promote hair and / or body hair growth. Summary of the Invention

[0021] The first object of this invention is the genus Iris ( Iris spp. The root and rhizome extract is used for cosmetic purposes to limit hair and / or body hair loss and / or promote hair and / or body hair growth.

[0022] The present invention also relates to the use of Iris rhizome extract in the preparation of cosmetic compositions for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth.

[0023] The present invention also relates to an Iris rhizome extract for use in limiting hair and / or body hair loss and / or promoting hair and / or body hair growth.

[0024] A second object of the present invention is the use of a cosmetic composition for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth, said cosmetic composition comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient.

[0025] The present invention also relates to a cosmetic composition for use in limiting hair and / or body hair loss and / or promoting hair and / or body hair growth, said cosmetic composition comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient.

[0026] A third object of the present invention is a cosmetic method for treating hair and / or body hair, particularly for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth, said method comprising the application, preferably topical application of at least one Iris rhizome extract or at least one cosmetic composition comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient, particularly applied to hair and / or scalp.

[0027] The present invention also relates to the use of Iris rhizome extract or cosmetic compositions comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient for blocking OR8D1 olfactory receptors and / or inhibiting the JAK-STAT signaling pathway and / or activating the Wnt / β-catenin pathway.

[0028] The present invention also relates to a method for blocking OR8D1 olfactory receptors and / or inhibiting the JAK-STAT signaling pathway and / or activating the Wnt / β-catenin pathway, comprising administering to a person in need an Iris rhizome extract or a cosmetic composition comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient.

[0029] Other aspects of the invention are described below. Detailed Implementation

[0030] Surprisingly, the inventors discovered that a rhizome extract from at least one species of the genus *Iris* can limit hair and / or body hair loss and / or promote hair and / or body hair growth. The extract exhibits beneficial activity against the OR8D1 olfactory receptor, which is involved in the regulation of hair growth. Furthermore, the extract also possesses JAK / STAT pathway inhibitory and Wnt / β-catenin pathway activating activities, which can be used to limit hair and body hair loss and promote hair and body hair growth.

[0031] definition In this invention, the genus Iris ( Iris Tourn. ex L.) can be simply referred to as Iris ( Iris Different species of the genus Iris can be simply referred to as the genus Iris ( Iris spp. These specifically include the German iris ( ). Iris x germanica. L.), Florentine Iris ( Iris florentina L. ) and iris root ( Iris pallida Lam).

[0032] In this invention, the plant *Iris tectorum* (German iris) Iris x germanica L.) can be simply referred to as German Iris (L.) Iris germanica Florentine iris (plant) Iris florentina L.) can be simply referred to as Florentine Iris ( Iris florentina ); Iris tectorum ( Iris pallida Lam can be simply referred to as Iris tectorum ( Iris pallida ).

[0033] "Rhizome" refers to the underground part of plants in the genus Iris.

[0034] In this invention, "Iris rhizome extract" refers to a product extracted from the rhizome of at least one plant belonging to the genus Iris as defined above. Preferably, it is an extract obtained from the rhizome of German Iris, Florentine Iris, or Fragrant Iris.

[0035] For the purposes of this invention, "extracted product" refers to the product obtained after extracting all or part of a plant with a solvent (referred to as the extraction solvent); that is, a product present in the extraction solvent, which may be in a concentrated or dried form after the extraction solvent has been partially or completely evaporated. It may be a dry extract.

[0036] For the purposes of this invention, "dry extract" refers to an extract that does not contain an extraction solvent or carrier, or an extract that contains only negligible trace amounts of an extraction solvent or carrier. Therefore, such a dry extract contains only substances obtained through the extraction of Iris spp.

[0037] For the purposes of this invention, "carrier" refers to a substance that enables the extract according to the invention to be dissolved or dispersed therein in a uniform manner (e.g., by adsorption).

[0038] In this invention, “about” means that the relevant value may be 10% lower or higher than the value shown, particularly 5%, particularly 2%, and even more particularly 1%.

[0039] For the purposes of this invention, "polar solvent" refers to a solvent specifically selected from water, subcritical water, glycerol, and mixtures thereof.

[0040] For the purposes of this invention, "medium polar solvent" refers to a solvent particularly selected from C1-C5 alcohols, C3-C5 diols (e.g., propylene glycol, butylene glycol, butanediol, or pentanediol), acetone, C1-C6 alkyl esters (e.g., C1-C6 alkyl acetates, especially ethyl acetate or isopropyl acetate), triethyl citrate, mixtures thereof with water (e.g., water-alcohol mixtures, more particularly C1-C5 alcohol / water mixtures, or acetone / water mixtures), solvents for aqueous solutions and mixtures thereof.

[0041] For the purposes of this invention, "nonpolar solvent" refers to solvents selected from, for example, heptane, hexane, limonene, ethyl oleate, halogenated hydrocarbons (e.g., C1 to C3 chlorinated hydrocarbons, such as chloroform or dichloromethane), supercritical CO2, mixtures of supercritical CO2 and ethanol (preferably with a supercritical CO2 / ethanol ratio of at least 70 / 30 (w / w)), and bio-based solvents (e.g., EcoXtract® LIPOCOS (supplier Pennakem Europe) and mixtures thereof).

[0042] A "water-soluble solution" refers to a mixture of water and a water-soluble agent.

[0043] "Hydrotropism" refers to a water-soluble amphiphilic molecule that, from a certain concentration onwards, can be extracted by solubilizing hydrophobic compounds and, in particular, moderately polar compounds in water.

[0044] "Water-alcohol mixture" refers to a mixture of water and one or more water-miscible alcohols (especially C1 to C5 alcohols, such as ethanol). The ratio of alcohol (e.g., C1 to C5 alcohols, such as ethanol) to water is advantageously 9.5:0.5 to 1:9 (v / v), especially 9.5:0.5 to 1:1 (v / v), preferably 9:1 to 6:4 (v / v), for example 8:2 to 6:4 (v / v), especially about 7:3 (v / v).

[0045] For the purposes of this invention, "supercritical CO2 extraction" refers to extraction using CO2 in a supercritical state (i.e., subjected to pressures and temperatures exceeding its critical point). Therefore, the temperature must be above 31°C and the pressure above 74 bar. In the supercritical phase, CO2 is a completely neutral, non-toxic, non-polluting, and non-flammable solvent, enabling the extraction of lipophilic compounds. The polarity of supercritical CO2 can be altered by adding a polar co-solvent such as ethanol to broaden the polarity range of the extracted molecules. Therefore, supercritical CO2 extraction is a preferred alternative to petrochemical solvents such as hexane or heptane.

[0046] "Isopallasson C" refers to the molecule (3-((Z)-heptadecane-9-enyl)-2-hydroxy-5-methoxycyclohexane-2,5-diene-1,4-dione) with the molecular formula C24H38O4 and a molar mass of 390.56 g / mol. As described in patent application KR2006-0045694, it has the following structure: For the purposes of this invention, the "isomer" of isomalacin refers to a molecule with the empirical formula C24H38O4, that is, a molecule with the same molecular formula as isomalacin. Therefore, it is a structural isomer.

[0047] The term "extract does not contain" a molecule is understood to mean that the molecule is not present in the extract as described in this invention, or that its possible presence cannot be detected because it is below the detection limit of suitable conventional detectors (diode array detectors (DADs) or charged sol detectors (CADs) and / or high-resolution mass spectrometers (HRMS)).

[0048] "Hair and body hair" refers to head hair, body hair, eyebrows, eyelashes and / or animal fur, with head hair being preferred.

[0049] "Appendages" refers to hair, body hair, eyebrows and / or eyelashes, with hair being preferred.

[0050] "Hair and / or body hair loss" refers to the loss of all or part (preferably part) of hair and / or body hair, for example, due to reduced hair growth and / or accelerated hair loss. The consequences of hair and / or body hair loss include temporary or permanent, partial or complete absence of hair and / or body hair.

[0051] "Restriction" means to stop, slow down, reduce, alleviate, weaken and / or prevent.

[0052] "Restricting hair and / or body hair loss" means, in particular, mammals, preferably humans, stopping, reducing, and mitigating hair and / or body hair loss.

[0053] "Promote" means to enhance, increase, contribute to, expand and / or accelerate.

[0054] "Promoting hair and / or body hair growth" means increasing hair and / or body hair growth, accelerating hair and / or body hair growth, promoting hair and / or body hair regeneration, increasing hair follicle density to achieve thicker hair, and / or promoting hair follicle regeneration. This also includes regulating the hair follicle cycle.

[0055] In this invention, "cosmetically acceptable" means that it can be used in the preparation of cosmetic compositions, is generally safe and non-toxic, and is not unsuitable in biological and other respects, and is acceptable for cosmetic uses, especially by topical application, particularly on hair and / or scalp.

[0056] "Cosmetic use" refers to the non-therapeutic use of the cosmetic effects of the Iris rhizome extract (alone or in a composition) according to the present invention, particularly for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth.

[0057] "Topical application" means application to the skin (especially the scalp), mucous membranes and / or appendages (especially hair and / or body hair), preferably to the skin and / or appendages, especially to hair and / or scalp.

[0058] Description of the implementation plan Iris genus extract This invention relates to the use of Iris rhizome extract for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth (especially hair growth).

[0059] The present invention also relates to the use of Iris rhizome extract for promoting hair regeneration.

[0060] The present invention also relates to the use of Iris rhizome extract for increasing hair follicle density and / or obtaining thicker hair and / or promoting hair follicle regeneration.

[0061] According to one embodiment, the iris rhizome extract is obtained from the rhizomes of *Iris tectorum*, *Iris florida*, *Iris florida*, or mixtures thereof. Therefore, the extract according to the invention is advantageously selected from rhizome extracts of *Iris tectorum*, *Iris florida*, *Iris florida*, and mixtures thereof.

[0062] More advantageously, the iris rhizome extract is obtained from the rhizome of German iris.

[0063] Preferably, the Iris rhizome extract is free of isomalacin, and more preferably free of isomalacin and its isomers.

[0064] In a particular embodiment of the invention, the Iris rhizome extract is obtained from cell cultures of Iris species (especially German Iris, Fragrant Iris, Florentine Iris, or mixtures thereof, preferably German Iris).

[0065] According to a preferred embodiment of the invention, the extract is obtained by supercritical CO2 extraction of Iris rhizomes (especially Iris derv. ...

[0066] According to a particular embodiment, the extract according to the invention can be obtained by the following method.

[0067] Iris rhizomes can be fresh or dried, whole, cut or ground, and then undergo an extraction step. Advantageously, Iris rhizomes are dried and ground before the extraction step.

[0068] In one embodiment of the invention, the dried and crushed rhizomes can be moistened with water before extraction.

[0069] The method for preparing the extract according to the invention includes an extraction step, more particularly by extracting Iris rhizomes with an extraction solvent selected from polar to nonpolar solvents and mixtures thereof, i.e., selected from polar solvents, moderately polar solvents, nonpolar solvents and mixtures thereof.

[0070] The plant weight / extraction solvent volume ratio can vary, particularly from 1 / 5 to 1 / 100. Extraction can last from 1 minute to 48 hours, especially from 1 hour to 24 hours. Extraction can be repeated 2 to 3 times.

[0071] In one embodiment, the extraction solvent may be selected from supercritical CO2 with or without the co-solvent ethanol, hexane, heptane, bio-based solvents of the EcoXtract® LIPOCOS type, ethyl oleate, ethyl acetate, isopropyl acetate, triethyl citrate, C3-C5 diols, C1-C5 alcohols, water-alcohol mixtures (especially C1-C5 alcohol / water mixtures), glycerol, aqueous solutions, water, and mixtures thereof.

[0072] Advantageously, the extraction solvent is supercritical CO2 with or without the co-solvent ethanol, hexane, heptane, bio-based solvents of the EcoXtract® LIPOCOS type, ethyl oleate, ethyl acetate, isopropyl acetate, triethyl citrate, C3-C5 diol, C1-C5 alcohol, or a water-alcohol mixture (e.g., a C1-C5 alcohol / water mixture).

[0073] More specifically, the extraction solvent will be selected from supercritical CO2, water-alcohol mixtures (e.g., C1-C5 alcohol / water mixtures), ethyl acetate, heptane, and water, preferably supercritical CO2.

[0074] More advantageously, the extraction solvent is supercritical CO2 with or without the co-solvent ethanol, or ethyl acetate.

[0075] Even more advantageously, the solvent is supercritical CO2 with or without ethanol as a co-solvent, i.e., supercritical CO2 that can be mixed with ethanol, wherein the supercritical CO2 remains the primary solvent. The supercritical CO2 / ethanol ratio is preferably at least 70 / 30 (w / w). Preferably, the extraction solvent is supercritical CO2.

[0076] In the above embodiments, when supercritical CO2 is used with ethanol as a co-solvent, the supercritical CO2 / ethanol ratio is preferably at least 70 / 30 (w / w), particularly 70 / 30 to 99 / 1 (w / w).

[0077] In another specific embodiment, supercritical CO2 extraction is carried out at a temperature of 32°C to 55°C and a pressure of 200 bar to 600 bar. The plant weight / supercritical CO2 volume ratio can be 1 / 5 to 1 / 100, particularly 1 / 10 to 1 / 100. Extraction can last from 1 minute to 48 hours, particularly 1 to 24 hours. Extraction can be repeated 2 to 3 times.

[0078] In another specific implementation, at the end of the extraction, supercritical CO2 is used alone to continue the extraction to dry the plant.

[0079] Preferably, the extract obtained at the end of the extraction is filtered to recover a clear liquid phase free of particles. The resulting liquid phase can be concentrated more or less, or even to produce a dry extract.

[0080] In another embodiment, a carrier may be added during the concentration step to obtain an extract containing 1% to 80% by weight of the dry extract, particularly 20% to 60% by weight of the dry extract. The carrier may be maltodextrin, lactose, silica, acacia gum or gum arabic, glycerol or a glycerol / water mixture, glycol, vegetable oil, triethyl citrate, ethyl oleate, dioctyl carbonate, octyl-dodecanoate, caprylic / capric triglyceride, a water / solvent mixture (a solubilizer is a compound that can solubilize the extract in water) or a water / surfactant mixture, or any other cosmetically acceptable carrier, preferably a bio-based carrier, such as bio-based glycols, particularly C3-C5 (1,2-pentanediol; 1,3-butanediol; 1,3-propanediol…), esterified fatty acids, and co-water-soluble agents, such as alkyl glycosides (Sepiclear, Apyclean, APXC4…). Advantageously, the extract according to the invention is placed on a caprylic / capric triglyceride carrier.

[0081] As described above, Iris rhizome extract can limit hair and / or body hair loss and / or promote hair and / or body hair growth.

[0082] Furthermore, the use of the extract according to the present invention enables the promotion of hair regeneration.

[0083] The use of the extract according to the invention enables a particular increase in hair follicle density and / or the attainment of thicker hair and / or the promotion of hair follicle regeneration.

[0084] According to one embodiment of the invention, the extract according to the invention is intended for topical application, and is therefore in a form suitable for such topical application.

[0085] Cosmetic composition The present invention also relates to the use of cosmetic compositions for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth (especially capillary growth), said cosmetic compositions comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient.

[0086] The cosmetic compositions according to the present invention can increase hair follicle density and / or achieve thicker hair and / or promote hair follicle regeneration.

[0087] The cosmetic compositions according to the present invention can also promote hair and / or body hair regeneration, especially hair regeneration.

[0088] Advantageously, the extracts included in the cosmetic composition are as described above.

[0089] Advantageously, the cosmetic composition comprises an extract obtained by supercritical CO2 extraction, namely, a supercritical CO2 extract of Iris rhizomes, particularly a supercritical CO2 extract of Iris truncatum, Iris truncatum var. praecox, Iris florida, or a mixture thereof, preferably a supercritical CO2 extract of Iris truncatum.

[0090] The cosmetic composition may contain 0.01% to 5%, preferably 0.01% to 4%, more preferably 0.01% to 2%, and even more preferably 0.01% to 1% of Iris extract relative to the total weight of the composition by weight of the dry extract. This percentage by weight of the dry extract does not include the weight of any carrier (if present) and therefore refers only to the dry plant extract.

[0091] The cosmetic composition according to the invention is preferably in a form suitable for topical application, particularly suitable for topical application to the scalp and / or hair.

[0092] Therefore, the cosmetic compositions according to the invention can be in forms commonly known for topical application, i.e., in particular lotions, shampoos, balms, mousses, gels, dispersions, emulsions, sprays, serums, masks or creams, having excipients that are particularly capable of penetrating to improve the properties and accessibility of the active ingredients.

[0093] Therefore, it is possible to distinguish between rinseable formulations and formulations that do not require rinsing.

[0094] Preferably, the cosmetic composition according to the invention has a lightweight texture, which further enables optimal penetration without making hair and / or body hair, or scalp oily.

[0095] In addition to the extracts described above, the cosmetic compositions according to the invention (e.g., for topical application) typically contain a physiologically acceptable medium, usually water-based or solvent-based, such as alcohols, ethers, or glycols. It may also contain surfactants, complexing agents, preservatives, stabilizers, emulsifiers, thickeners, gelling agents, humectants, emollients, trace elements, essential oils, fragrances, colorants, moisturizers, and / or thermal spring water, etc.

[0096] From the first application (e.g., topical or oral) of the composition according to the invention, hair will regain strength and vitality, and will promote regeneration.

[0097] The composition described above can be used in particular to promote hair regeneration.

[0098] According to one embodiment of the present invention, the cosmetic composition described above is intended to be applied topically.

[0099] Cosmetic method: The present invention also relates to a cosmetic method for treating hair and / or body hair, particularly for limiting hair and / or body hair loss and / or promoting hair and / or body hair growth, the method comprising the application, preferably topical application of at least one Iris rhizome extract or at least one cosmetic composition comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient, particularly applied to hair and / or scalp.

[0100] This method is particularly helpful in promoting hair and / or body hair regeneration, especially scalp regeneration.

[0101] This method can also increase hair follicle density and / or result in thicker hair and / or promote hair follicle regeneration.

[0102] Iris rhizome extract is more particularly the extract as defined above, and cosmetic composition is more particularly the cosmetic composition as defined above.

[0103] Example The following examples illustrate the invention but do not limit its scope. Examples 1 to 6 illustrate different types of extractions used to prepare rhizome extracts of German iris (Examples 1 to 4), Florentine iris (Example 5), and fragrant iris (Example 6). Example 7 confirms the absence of isoisine and its isomers in these extracts, and Examples 8 to 10 highlight the effects of these extracts on limiting hair loss and promoting hair growth.

[0104] Example 1: Extraction of German iris using supercritical CO2, followed by incorporation into a carrier. 300 g of dried and ground *Iris tectorum* rhizomes were extracted using supercritical CO2 at a flow rate of 10 kg / h for 180 minutes at a pressure of 250 bar and a temperature of 40°C. After expansion to atmospheric pressure and restoration to room temperature, the extract was collected, filtered, and supplemented with an octanoic acid / capric acid triglyceride carrier. The resulting extract contained 45% dried *Iris tectorum* rhizome extract and 55% octanoic acid / capric acid triglycerides.

[0105] Example 2: Water-alcohol reflux extraction of German iris In a reactor, 100 g of dried and ground German iris rhizomes were refluxed with 1 L of a 70:30 (v / v) ethanol / water mixture for 1 hour with stirring. The extract was then filtered through a K900 filter plate and dried under vacuum to obtain 24 g of dry extract.

[0106] Example 3: Ethyl acetate extraction of German iris at room temperature In a reactor, at room temperature and with stirring, 100 g of dried and ground German iris rhizomes were extracted with 1 L of ethyl acetate for 14 hours. The extract was then filtered through a K900 filter plate and dried under vacuum to obtain 2.3 g of dry extract in the form of an oily paste.

[0107] Example 4: Heptane extraction of German iris at room temperature In a reactor, at room temperature and with stirring, 500 g of dried and ground German iris rhizomes were extracted with 500 mL of heptane for 1 hour. The extract was then filtered through a K900 filter plate and dried under vacuum to obtain 2.5 g of dry extract in the form of an oily paste.

[0108] Example 5: Water extraction of Florentine iris at room temperature In a reactor, at room temperature and with stirring, one kilogram of dried and ground Florence iris rhizomes were extracted using 10 liters of water overnight. The extract was then filtered through a K900 filter plate and dried under vacuum to obtain 260 grams of dry extract.

[0109] Example 6: Water-alcohol reflux extraction of iris root In a reactor, 500 g of dried and ground iris rhizomes were refluxed with 5 L of a 70:30 (v / v) ethanol / water mixture for 1 hour under stirring. The extract was then filtered through a K900 filter plate and dried under vacuum to obtain 130 g of dry extract.

[0110] Example 7: Evaluation of the presence of isoisine and its isomers in Iris extracts Sample preparation: Dissolve 20 mg of the extract to be analyzed in 400 µL of a suitable recovery solvent to obtain a stock solution of 50 mg / ml, wherein the recovery solvent is selected from water, ethyl acetate, dimethyl sulfoxide (DMSO), or a mixture of DMSO and water or ethyl acetate.

[0111] Dilute 30 µL of the stock solution in 120 µL of a suitable solvent consisting of water, methanol, or ethyl acetate to obtain a completely clear solution.

[0112] For example: - Dissolve 20 mg of the extract obtained according to Example 1 in 400 µL of ethyl acetate, and then dilute 30 µL of the resulting solution in 120 µL of ethyl acetate; - Dissolve 20 mg of the extract obtained according to Example 2 in 400 µL of DMSO, and then dilute 30 µL of the resulting solution in 120 µL of methanol. - Dissolve 20 mg of the extract obtained according to Example 3 in 400 µL of DMSO, and then dilute 30 µL of the resulting solution in 120 µL of ethyl acetate; - Dissolve 20 mg of the extract obtained according to Example 4 in 400 µL of a DMSO / ethyl acetate (1:1) (v / v) mixture, and then dilute 30 µL of the resulting solution in 120 µL of ethyl acetate; - Dissolve 20 mg of the extract obtained according to Example 5 in 400 µL of a DMSO / water (1:1) (v / v) mixture, and then dilute 30 µL of the resulting solution in 120 µL of water.

[0113] Analysis conditions: - Instrument: UHPLC-Acquity / DAD / Synapt G2Si - Column: Acquity UPLC HSS C18 T3 2.1 mm x 100 mm 1.8µm (Waters) - Mobile phase: • A: Water + 0.1% formic acid • B: Acetonitrile - Based on the gradient of the conditions in Table 1: [Table 1] - Chamber temperature: 40°C - Injection volume: 2 µL - UV acquisition: 200–500 nm - High-resolution mass spectrometry acquisition: - Acquisition Mode: Centroid - Acquisition type: DDA (CE: Ramp) | Neg - HRMS resolution: resolution - Acquisition Mode: Continuous Acquisition - Acquisition type: MSe (CE: Ramp) | Neg & Pos - HRMS resolution: resolution The Synapt-G2Si high-resolution mass spectrometer was calibrated with sodium formate solution, and m / z measurements were performed in the range of 100 to 1200 Thomson (Th), with an accuracy of less than 1 millidalton (mDa) for all ions of interest. During acquisition, leucine enkephalin was injected every 20 seconds to maintain instrument calibration, and two ions, 554.2615 Th and 236.1035 Th, were used as reference points.

[0114] The instrument has four acquisition modes: one with high m / z measurement resolution (35k) but lower sensitivity; or one with lower m / z measurement resolution (15k) but increased sensitivity. Acquisition was performed in the sensitive mode to ensure optimal sensitivity for detecting low-intensity ions. In the negative ion mode, a search for signals of interest was conducted for "-H" and "+HCOOH-H" adducts, which were most frequently observed on the instrument when formic acid (0.1% v / v in this case) was used as an additive in the aqueous phase.

[0115] To generate empirical formulas based on observed m / z values, an m / z measurement precision of 3 mDa (7.7 ppm at a single isotopic mass of 390) was used. Any values ​​higher than this are irrelevant. It is important to consider that this limit is high, but for trace detection purposes. Regarding the intensity of the m / z peak, again for trace detection purposes, a low limit (1000 absolute units) was used; this value is lower than the intensity typically observed during annotation.

[0116] Under these conditions, no trace of isomalacin or any of its isomers was detected in the extracts of Examples 1, 2, 3, 4, 5 and 6.

[0117] Example 8: The involvement of olfactory receptor OR8D1 Olfactory receptors are primarily expressed in nasal epithelial cells. However, their expression has also been detected in several other human tissues, where they play roles unrelated to olfaction. Ralf Paus's team has shown that the olfactory receptor OR2AT4 is expressed in the epithelial cells of human hair follicles and can regulate hair growth (Chéret et al., 2018).

[0118] In clinical studies, the inventors demonstrated that, compared with volunteers who did not experience hair loss, volunteers with confirmed hair loss had overexpression of the olfactory receptor OR8D1 in their hair follicles.

[0119] Sotolon is an OR8D1 receptor agonist that promotes the transition to the mid-stage of hair growth.

[0120] Therefore, the inventors investigated the effects of two known antagonists of the olfactory receptor OR8D1 on hair follicles in vitro. The antagonists were 2-ethylfentanyl alcohol and α-isomethylionone.

[0121] These two molecules, tested at 3 µM, prolonged the early stages of hair growth.

[0122] The inventors then tested the Iris extract prepared according to Example 1 to evaluate its effects on different stages of the hair cycle.

[0123] The extract dissolved in ethanol was tested at 10 µg / ml (a solvent control containing 0.1% ethanol was evaluated).

[0124] Experiments were conducted on human hair follicles obtained through surgical procedures. These experiments were performed on hair follicles from two different donors.

[0125] Hair follicles were microdissected and cultured in 48-well plates, one follicle per well. Cultured at 37°C and 5% CO2 in Williams E medium (Gibco Life Technologies) supplemented with L-glutamine (2 mM), hydrocortisone (10 ng / ml), insulin (10 µg / ml), and a penicillin / streptomycin mixture (1%).

[0126] Photographs of each hair follicle were taken every two days (magnification x50). Photographs at magnification x200 were also taken and analyzed on the first day (D1) and the last day (D11) of the study.

[0127] After a 3-day control period, the culture medium was changed, and either Iris extract or a carrier (0.1% ethanol) was added. From day 5 (D5) to day 10, if at least 20% of the hair follicles in the carrier group were in the early stages of hair growth, the decision to continue culture was confirmed. On day 6, the culture medium was changed again, and either Iris extract or a carrier (0.1% ethanol) was added back to the medium.

[0128] The results are summarized in Table 2 below.

[0129] [Table 2] The inventors emphasize that Iris extract can prolong the early stage of hair growth in the hair cycle through the olfactory receptor OR8D1, thereby promoting hair growth.

[0130] Example 9: Evaluation of German Iris Extract in the JAK-STAT Pathway The aim of this embodiment was to confirm the inhibitory activity of the JAK-STAT signaling pathway in an extract of *Iris tectorum* in a cell model. In this model, the JAK1 / 2-STAT3 pathway was activated using interleukin IL-6 by activating the IL-6 receptor expressed in the epithelial sheath of the hair follicle. IL-6 is a cytokine that acts as an inhibitor of the hair growth cycle; its overexpression in a transgenic mouse model causes delayed hair growth. Furthermore, in androgenetic alopecia, IL-6 has been reported to be overexpressed in dermal papillary cells under the influence of androgens (Kwack et al., 2012). IL-6 has also been reported to delay hair follicle growth in humans.

[0131] The study was conducted on follicular keratinocytes derived from the outer root sheath of hair follicles (ORS model). Keratinocytes were cultured in 96-well plates in a suitable medium (Cellntec CnT-PR). After 48 hours, the cells were washed with alkaline phosphate-buffered saline (PBS) and replaced with KSFM medium (the standard maintenance medium for primary human keratinocytes). After 4 hours, the cells were tested with the test substance (Iris tectorum extract according to Example 1, diluted in ethanol to 50 and 100 µg / m³). 3 Cells were treated with either the reference compound (tofacitinib, diluted to 5 µm in DMSO) for 1 hour. Then, they were stimulated with IL-6 at 100 ng / ml (Stim IL6) for 15 minutes.

[0132] All experimental conditions were repeated with n=3 donors and n=3 techniques.

[0133] The activation level of the JAK / STAT signaling pathway was estimated by assessing the phosphorylation level of STAT3 protein using the commercial Cisbio 62AT3PEG or Cisbio 64NT3PEG kit (Perkin Elmer). Statistical analysis was performed using parametric tests after validating for normality and homogeneity of variance; otherwise, nonparametric tests were used.

[0134] The results are presented in Table 3 below.

[0135] [Table 3] SEM = Standard Mean Error *: p<0.001 vs DMSO 0.1% + stimulating IL6 **: p<0.01 vs 0.1% ethanol + stimulation of IL6 ***: p<0.001 vs 0.2% ethanol + stimulating IL6 Treatment of keratinocytes with IL-6 induced a significant increase in STAT3 phosphorylation levels, thereby inhibiting the JAK / STAT pathway. The reference compound (tofacitinib, tested at 5 µM) significantly reduced STAT3 phosphorylation levels by 97.5%. These expected results validated the assay.

[0136] The German iris extract obtained according to Example 1 significantly and very obviously inhibited the level of STAT3 phosphorylation induced by IL-6 stimulation.

[0137] Therefore, the inventors emphasize the benefits of German iris extract, namely, by significantly inhibiting the activation of the JAK / STAT pathway induced by IL6 in outer epithelial sheath cells, it prolongs the hair life cycle, thereby limiting hair loss and promoting hair growth.

[0138] Example 10: Evaluation of the activation of the Wnt / β-catenin pathway by several Iris extracts The development and growth of hair follicles are influenced by compounds and proteins such as Wnt expressed by the dermal papilla, and growth factors such as keratinocyte growth factor (KGF) or epidermal growth factor (EGF).

[0139] Hair is constantly being renewed; of the 100,000 to 150,000 hairs in a head, the majority are in the growth phase. In healthy hair follicles, about 60 to 100 hairs fall out daily—a normal physiological process. Anything exceeding this is considered pathological, whether it occurs occasionally or continuously.

[0140] Wnt is a family of glycoproteins, named after the combination of Wg (wingless gene) and Int (integration site). The Wnt protein signaling pathway via β-catenin is known as the classical pathway, meaning it is the preferred pathway. Wnt signaling activates hair regeneration and contributes to hair growth. Wnt binds to extracellular receptors, stabilizing intracellular β-catenin and preventing its degradation by the proteasome. β-catenin can then enter the nucleus and act as a coactivator of transcription factors, stimulating the expression of specific genes involved in hair growth, such as those encoding KGF.

[0141] Hair development depends on a signaling circuit between keratinocytes and dermal papilla cells. Wnt expression in keratinocytes induces an increase in β-catenin in dermal papilla cells, thereby regulating signaling pathways including those involving growth factors that guide hair morphogenesis. KGF is an important endogenous paracrine mediator in hair follicle development, differentiation, and growth. β-catenin and KGF are highly present in the early stages of hair growth and then disappear. Loss of β-catenin expression blocks Wnt signaling and induces a transition to the mid-stage of hair growth.

[0142] These experiments were performed on human cells derived from the dermal papillae of hair follicles from three donors. Cells were seeded in 96-well plates and cultured for 24 hours in HFDPC medium (Promocell) containing the necessary complement. Cells were then incubated with a polybrene infection / transfection reagent (Sigma #TR-1003-G) and transduced with a TCF / LEF luciferase reporter gene lentivirus (Wnt / β-catenin signaling pathway) (BPS Bioscience #79787 lot 2201024), which expresses the luciferase gene under the control of the Wnt / β-catenin promoter (TCF / LEF transcriptional response element). The cells were then incubated for 24 hours with the following products to be tested: German iris extract diluted in DMSO (5, 10, 50, or 100 µg / ml), Florentine iris extract diluted in DMSO (5, 10, or 50 µg / ml), or vetiver iris extract diluted in DMSO (5, 10, 50, or 100 µg / ml). The tested extracts were obtained under the following different extraction conditions: - EtOH70 extraction performed according to the conditions of Example 2 or 6, regardless of the iris species, - AcEth extraction performed according to the conditions of Example 3, regardless of iris species, and - n-Hep extraction performed according to the conditions of Example 4, regardless of iris species, - Water extraction performed according to the conditions of Example 5, regardless of the iris species.

[0143] A positive control (10 µM apigenin) and a control for TCF / LEF reporter gene stimulation (10 mM Wnt3a) were also tested. Activation of the Wnt / β-catenin pathway was highlighted by quantifying luminescence induced by luciferase expression.

[0144] Wnt / β-catenin activity was assessed and quantified after reading luminescence associated with luciferase reporter gene expression controlled by the Wnt / β-catenin promoter (TCF / LEF).

[0145] Table 4 below shows the activation of the Wnt / β-catenin pathway after incubation with German iris extracts obtained according to different extraction types.

[0146] [Table 4] Table 5 below shows the activation of the Wnt / β-catenin pathway after incubation with Florence Iris extracts obtained according to different extraction types.

[0147] [Table 5] Table 6 below shows the activation of the Wnt / β-catenin pathway after incubation with iris extracts obtained according to different extraction types.

[0148] [Table 6] The inventors have demonstrated that iris rhizome extract is active against the Wnt / β-catenin pathway, regardless of the iris species or the type of extraction performed. This reflects the potential of iris rhizome extract to promote hair regeneration.

[0149] References: KR2006-0045694; Jean Bruneton, Pharmacognosie Phytochimie Plantes médicinales Ed. Lavoisier, 5th edition, 2015, pp. 727-728; Chéret et al., Olfactory receptor OR2AT4 regulates human hair growth. Nat Commun 2018, 18, 9(1): 3624; Pr.Pierre Delaveau, Expliquez-moi les plantes, Ed.Pharmathèmes, 2003, p.305; Hadfield et al., A High-Yielding Synthesis of the Naturally Occurring Antitumor Agent Irisquinone, Molecules 2000, 5, 82-88; Iwashina and Mizuno, Flavonoids and xanthones from the Genus Iris: phytochemistry, relationships with flower colors and taxonomy, and activities and function, Natural Product Communications 2029, 15(10) 1-35; Kwack et al., Dihydrotestosterone-Inducible IL-6 Inhibits Elongation of Human Hair Shafts by Suppressing Matrix Cell Proliferation and Promotes Regression of Hair Follicles in Mice, J Invest Dermatology 2012, 132(1) 43-9; Rahman et al., Two New Quinones from Iris bungei, Chem. Pharm. Bull. 2000, 48(5), 738-739; Wang et al., Flavonoids of the Genus Iris (Iridaceae), Mini-reviews in Medicinal Chemistry 2010, 10(7), 643-661.

Claims

1. Iris rhizome extract is used for cosmetic purposes to limit hair loss and / or promote hair growth.

2. The use of the extract according to claim 1, which is for promoting hair regeneration.

3. Use of the extract according to any one of claims 1 to 2, for increasing hair follicle density and / or obtaining thicker hair and / or promoting hair follicle regeneration.

4. The use of the extract according to any one of claims 1 to 3, characterized in that, The extract is in a form suitable for topical application.

5. The use of the extract according to any one of claims 1 to 4, characterized in that, The extracts are selected from the rhizome extracts of German iris, Florentine iris, and fragrant iris, and mixtures thereof.

6. The use of the extract according to any one of claims 1 to 5, characterized in that, The extract is obtained by extracting Iris rhizomes with an extraction solvent selected from supercritical CO2, a water-alcohol mixture, ethyl acetate, heptane and water, preferably by supercritical CO2 extraction.

7. The use of a cosmetic composition for limiting hair loss and / or promoting hair growth, said cosmetic composition comprising at least one Iris rhizome extract and at least one cosmetically acceptable excipient.

8. The use of the cosmetic composition according to claim 7, characterized in that, The composition comprises 0.01% to 5% of the extract relative to the total weight of the composition, based on the weight of the dry extract.

9. The use of the cosmetic composition according to any one of claims 7 to 8, characterized in that, The extract is obtained by extraction with an extraction solvent selected from supercritical CO2, a water-alcohol mixture, ethyl acetate, heptane and water, preferably by supercritical CO2 extraction.

10. The use of the cosmetic composition according to any one of claims 7 to 9, characterized in that, The composition is in a form suitable for topical application.

11. Use of the cosmetic composition according to any one of claims 7 to 10, wherein it is for promoting hair regeneration.

12. Use of the cosmetic composition according to any one of claims 7 to 11, for increasing hair follicle density and / or obtaining thicker hair and / or promoting hair follicle regeneration.

13. A cosmetic method for treating hair, particularly for limiting hair loss and / or promoting hair growth, comprising applying at least one cosmetic composition containing at least one Iris rhizome extract and at least one cosmetically acceptable excipient.

Images