4. Use of 4-octyl itaconic acid in the manufacture of a product for the broad spectrum protection against skin photodamage and / or the prevention and / or treatment of skin photoaging.

Abstract

The application provides application of 4-octyl itaconic acid in preparation of a broad-spectrum anti-skin light damage and / or prevention and treatment of skin photoaging product, and belongs to the technical field of biotechnology. The application provides a broad-spectrum anti-skin light damage composition, which comprises an active ingredient and an auxiliary material; the active ingredient comprises 4-octyl itaconic acid; and the auxiliary material comprises polyethylene glycol 300 and a PBS buffer. The composition provided by the application has the advantages of high safety, rapid effect on acute light damage (sunburn), and remarkable anti-inflammatory and repair effects. The composition provided by the application can restore the epidermal barrier function of sunburned skin, relieve the formation of wrinkles in photoaged skin, restore the epidermal barrier function of photoaged skin, improve the abnormal hyperplasia of the stratum corneum and inflammatory infiltration of photoaged skin, and improve the fracture and structural disorder of collagen fibers in photoaged skin, thereby effectively reversing the ultraviolet-induced collagen degradation and structural damage.

Description

Technical Field

[0001] This invention belongs to the field of biotechnology, specifically relating to the application of 4-octyl itaconic acid in the preparation of broad-spectrum anti-skin photodamage and / or anti-skin photoaging products. Background Technology

[0002] As people place increasing importance on skin care, the development of skin protection products and cosmetics against photodamage is also accelerating. However, existing photodamage protection products still have several problems: 1. Irritation: Many traditional chemical sunscreens (such as avobenzone and oxybenzone) or high-concentration repair ingredients, while reducing UV damage to some extent, can easily cause skin irritation, erythema, allergies, and other irritations, which are particularly difficult for people with sensitive skin to tolerate. 2. Safety: Some synthetic anti-inflammatory or antioxidant ingredients have potential systemic absorption risks. Long-term use may interfere with the normal skin microecology or cause chronic toxicity accumulation. Their safety for special populations such as pregnant women and children is not yet clear. 3. Limited effectiveness: Most existing products focus on physical or chemical shielding against UV rays, but their ability to actively repair existing photodamage (such as DNA damage, mitochondrial dysfunction, collagen degradation, and pigmentation) is insufficient. They are unable to achieve a full-chain intervention from prevention to repair, and their reversal effect on deep photoaging is weak. The existence of these problems not only causes skin problems for consumers and affects their quality of life, but also increases the risk burden of skin care selection and use. Therefore, finding a highly effective, safe product that combines anti-inflammatory and repair functions to combat photodamage to the skin is a critical issue that urgently needs to be addressed in this field. Summary of the Invention

[0003] In view of this, in order to solve the problems of high irritation, insufficient safety and limited repair effect of existing anti-photodamage products, the present invention provides a broad-spectrum anti-photodamage composition for the skin, which can not only significantly enhance the anti-photodamage effect, but also significantly reduce UV-induced sunburn, promote the repair of the epidermal barrier function of photo-aged skin, and has no obvious toxic side effects on major organs, and has the characteristics of safety and high efficiency.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a broad-spectrum composition for resisting photodamage to the skin, comprising an active ingredient and excipients, wherein the active ingredient comprises 4-octylitaconic acid, and the excipients comprise polyethylene glycol 300 and PBS buffer.

[0005] Preferably, the mass-volume concentration of 4-octylitaconic acid in the composition is 5~150 mg / mL; and the volume ratio of polyethylene glycol 300 to PBS buffer is (0.5~2):1.

[0006] Preferably, the active ingredient also includes ginkgo biflavonoids.

[0007] Preferably, the mass ratio of 4-octyl itaconic acid to ginkgo biflavonoids is (1~10):(0.1~2).

[0008] The present invention also provides a method for preparing the above composition, comprising the following steps: mixing the excipient components and then mixing them with the active ingredient to obtain the composition.

[0009] Preferably, the method further includes a storage step, wherein the storage is to freeze the composition at -80°C or below in the dark.

[0010] The present invention also provides the use of the above composition in the preparation of products for broad-spectrum protection against skin photodamage and / or prevention of skin photoaging.

[0011] This invention also provides the application of 4-octyl itaconic acid in the preparation of broad-spectrum anti-skin photodamage and / or anti-skin photoaging products.

[0012] This invention also provides the application of 4-octyl itaconic acid and ginkgo biflavonoids in the preparation of broad-spectrum anti-skin photodamage and / or anti-skin photoaging products.

[0013] Preferably, the mass ratio of 4-octyl itaconic acid to ginkgo biflavonoids is (1~10):(0.1~2).

[0014] The beneficial effects of this invention are: The composition provided by this invention has the advantages of high safety, rapid onset of action on acute photodamage (sunburn), and significant anti-inflammatory and repair effects. The composition provided by this invention can restore the epidermal barrier function of sunburned skin, alleviate the formation of wrinkles in photo-aged skin, restore the epidermal barrier function of photo-aged skin, improve the abnormal proliferation and inflammatory infiltration of the stratum corneum in photo-aged skin, and improve the breakage and structural disorder of collagen fibers in photo-aged skin, thereby effectively reversing the collagen degradation and structural damage induced by ultraviolet rays.

[0015] The composition provided by this invention combines 4-octyl itaconic acid with ginkgo biflavonoids. The two exert their anti-photoaging effects through different but complementary molecular mechanisms, and can produce synergistic effects in anti-inflammatory, antioxidant, epidermal barrier repair and collagen degradation improvement, providing a more comprehensive intervention strategy for anti-photoaging. Attached Figure Description

[0016] Figure 1 Gross photographs of sunburned mice on day 1 of treatment in each group of experimental mice.

[0017] Figure 2 HE staining results of skin tissue from mice in each group of sunburned experimental mice.

[0018] Figure 3HE staining results of the heart, liver, spleen, lungs, and kidneys of mice in each group of sunburned experimental mice on day 7 of treatment.

[0019] Figure 4 The results of KRT14 immunofluorescence staining of skin tissue from mice in each group of sunburned experimental mice on day 7 of treatment.

[0020] Figure 5 These are macroscopic photographs of the skin photoaging status of mice in each photoaging group after 2 weeks of treatment.

[0021] Figure 6 The results of transepidermal water loss and stratum corneum water content of the skin of mice in each photoaging experimental group after 2 weeks of treatment are shown in the left figure, and the right figure shows the stratum corneum water content. * indicates p < 0.05, and ** indicates p < 0.01.

[0022] Figure 7 HE staining results of skin of mice in each photoaging group after 2 weeks of treatment.

[0023] Figure 8 Masson staining results of skin from mice in each photoaging group after 2 weeks of treatment.

[0024] Figure 9 The curves showing the weight change of mice in each photoaging group after 2 weeks of treatment are shown. ns indicates p > 0.05.

[0025] Figure 10 The results of GO functional enrichment analysis of skin tissue transcriptomes in various groups of experimental mice undergoing photoaging (Top 30 downregulated pathways compared to the model group in the 4-octyl itaconic acid treatment group). Detailed Implementation

[0026] This invention provides a broad-spectrum composition for resisting photodamage to the skin, comprising an active ingredient and excipients, wherein the active ingredient comprises 4-octylitaconic acid, and the excipients comprise polyethylene glycol 300 and PBS buffer.

[0027] This invention provides a composition containing 4-octyl itaconate, designed to offer a safe, effective, and stable solution for UV-induced sunburn (acute photodamage) and photoaging of the skin. This invention fills a gap in the application of 4-octyl itaconate in the prevention and treatment of sunburn and photoaging. 4-Octyl itaconate (4OI) is a derivative of itaconic acid with the molecular formula C0. 13 H 20 O4. This invention does not specifically limit the source of 4-octylitaconic acid; it can be obtained through self-extraction or commercial purchase. This invention also does not specifically limit the source of the excipients.

[0028] In the composition of this invention, the mass-volume concentration of 4-octylitaconic acid is preferably 5-150 mg / mL, more preferably 10-120 mg / mL, and even more preferably 11-110 mg / mL. The concentration of 4-octylitaconic acid in the composition provided by this invention maximizes its anti-sunburn and anti-photoaging effects while ensuring safety. In this invention, the volume ratio of polyethylene glycol 300 to PBS buffer is preferably (0.5-2):1, more preferably (0.8-1.5):1, and even more preferably 1:1. In this invention, polyethylene glycol 300 has good solubility, which helps 4-octylitaconic acid dissolve better; PBS buffer (Phosphate-Buffered Saline) can maintain the pH stability of the composition, ensuring that 4-octylitaconic acid remains active in a suitable environment. The combination of polyethylene glycol 300 and PBS buffer in this invention synergistically ensures the stability and effectiveness of the composition.

[0029] In the composition described in this invention, the active ingredient preferably also includes ginkgetin. This invention does not specifically limit the source of ginkgetin; commercially available products in the art are acceptable. In this invention, the mass ratio of 4-octyl itaconic acid to ginkgetin is preferably (1~10):(0.1~2), more preferably (3~7):(0.5~1.5), and even more preferably 5:1. When 4-octyl itaconic acid and ginkgetin are used in combination, this invention produces a significant synergistic effect. They exert their anti-photoaging effects through different but complementary molecular mechanisms: 4-octyl itaconic acid mainly works by regulating the NRF2-ARE antioxidant pathway and inhibiting inflammatory signaling pathways, while ginkgetin mainly exerts its anti-photoaging activity by directly scavenging ROS and inhibiting MMP-1 expression. The combined use of the two can simultaneously intervene in the photoaging process from multiple dimensions, including anti-oxidation, anti-inflammation, and inhibition of collagen degradation, achieving a more comprehensive and efficient anti-photoaging effect. In the composition of this invention, the concentration of ginkgo biflavonoids is preferably 5-20 mg / mL, more preferably 8-16 mg / mL, and even more preferably 10 mg / mL. In some embodiments of this invention, the composition is an injectable formulation, administered via intraperitoneal or intradermal injection; in other embodiments, the composition can also be formulated as a topical or transdermal formulation, acting directly on the surface and superficial tissues of the skin to improve the bioavailability of the components. When formulated as a topical or transdermal formulation, the preferred method of administration is to treat the skin with a roller followed by topical application of the composition.

[0030] The present invention also provides a method for preparing the above composition, comprising the following steps: mixing the excipient components and then mixing them with the active ingredient to obtain the composition.

[0031] In the preparation method of this invention, when mixing the excipients and active ingredients, stirring is preferably used to ensure that the active ingredients are completely dissolved at room temperature. The stirring speed is preferably 200-500 rpm, more preferably 250-450 rpm, and the stirring time is preferably 10-30 minutes, more preferably 15-25 minutes. After the active ingredients are completely dissolved, sterilization is preferably required. After sterilization, the composition can be used immediately to maximize its freshness and activity. If it is not to be used immediately, the prepared composition is preferably dispensed into sterile containers and frozen at -80°C or lower in the dark. Low temperature and light protection effectively slow down the degradation rate of 4-octyl itaconic acid, maintaining its activity. The freezing time is preferably no more than 6 months to ensure that its anti-sunburn and anti-photoaging effects are not significantly affected within the shelf life. When needed, the frozen composition is removed, thawed to room temperature in a water bath at no more than 37°C, shaken to mix well, and used immediately.

[0032] The composition provided by this invention has the following advantages: (1) High safety: HE staining of mouse heart, liver, spleen, lung and kidney showed no obvious cell degeneration, necrosis or inflammatory infiltration in any organ at the administered dose, indicating that it has few systemic side effects and is safe and reliable to use. (2) Rapid onset of action on acute photodamage (sunburn): Animal experiments showed that on the first day of treatment, the erythema and edema of the skin on the back of mice in the 4-octyl itaconic acid treatment group were significantly reduced and the damaged area was significantly reduced, indicating that the composition of this invention can quickly relieve the symptoms of sunburn induced by ultraviolet radiation. (3) Significant anti-inflammatory and repair effects: HE staining of skin showed that 4-octyl itaconic acid can significantly reduce inflammatory cell infiltration, protect the epidermal structure and promote the recovery of dermal collagen arrangement, confirming that it has good anti-inflammatory effects and the ability to promote the repair of skin damage caused by ultraviolet radiation. (4) Restoring the epidermal barrier function of sunburned skin: KRT14 immunofluorescence staining results showed that the KRT14 fluorescence signal was significantly enhanced in the 4-octyl itaconic acid treatment group, and the positive staining was continuously distributed in the basal layer and spinous layer, close to the level of the blank control group, indicating that the composition of the present invention can effectively restore the epidermal barrier function of sunburned skin induced by ultraviolet radiation. (5) Alleviating the formation of wrinkles in photoaged skin: Animal experiments showed that after 2 weeks of treatment, the wrinkles on the back of mice in the 4-octyl itaconic acid treatment group were significantly reduced and shallower than those in the model group, indicating that the composition of the present invention has a significant improving effect on ultraviolet radiation-induced photoaging of the skin. (6) Restoring the epidermal barrier function of photoaged skin: Through the detection of transepidermal water loss and stratum corneum water content, 4-octyl itaconic acid can significantly reduce transepidermal water loss and maintain the stratum corneum water content that is reduced due to ultraviolet radiation, indicating that the composition of the present invention can effectively repair the epidermal barrier function of photoaged skin. (7) Improves abnormal proliferation of stratum corneum and inflammatory infiltration in photoaged skin: HE staining results showed that 4-octyl itaconic acid can significantly reduce inflammatory cell infiltration and abnormal proliferation of stratum corneum in photoaged skin and improve epidermal structural disorder. (8) Improves collagen fiber breakage and structural disorder in photoaged skin: Masson staining results showed that the collagen fiber arrangement in the dermal layer of the back skin of mice in the 4-octyl itaconic acid treatment group was more regular than that in the model group, with reduced breakage and increased density, indicating that the composition of the present invention can effectively reverse UV-induced collagen degradation and structural damage. (9) Good safety with long-term use: In the 2-week photoaging treatment experiment, the body weight of mice in the 4-octyl itaconic acid treatment group showed a steady growth trend, with no significant difference compared with the blank control group and the model group (p>0.05), indicating that 4-octyl itaconic acid has no significant adverse effects on the feeding, metabolism and overall health of mice under long-term administration, further verifying its safety for long-term prevention and treatment of photoaging.(10) Inhibition of photoaging skin inflammation pathways at the transcriptional level: GO enrichment analysis of transcriptomics showed that, compared with the model group, multiple inflammation and immune-related pathways (including antigen processing and presentation, chemokine-mediated signaling pathways, inflammatory response, neutrophil chemotaxis, etc.) were significantly downregulated in the 4-octyl itaconic acid treatment group, indicating that 4-octyl itaconic acid can systematically inhibit ultraviolet-induced skin inflammation at the gene expression level, which is one of the important molecular mechanisms by which it exerts its anti-photoaging effect.

[0033] This invention also provides the use of the above composition in the preparation of broad-spectrum products for protecting against skin photodamage and / or preventing skin photoaging. In this invention, the products preferably include pharmaceuticals or cosmetics.

[0034] This invention also provides the application of 4-octyl itaconic acid in the preparation of broad-spectrum anti-photodamage and / or anti-photoaging products. Furthermore, this invention provides the application of 4-octyl itaconic acid and ginkgo biloba extract in the preparation of broad-spectrum anti-photodamage and / or anti-photoaging products.

[0035] The broad-spectrum anti-photodamage of the skin referred to in this invention refers to all skin damage caused by ultraviolet radiation, including acute photodamage and chronic photodamage. Acute photodamage is preferably UVB-mediated, such as sunburn, redness, peeling, immediate DNA damage, and barrier damage. Chronic photodamage preferably includes long-term cumulative damage and other photodamage consequences such as photoimmunosuppression, actinic keratosis, and photocarcinogenesis.

[0036] In the application described in this invention, the mass ratio of 4-octyl itaconic acid to ginkgo biflavonoids is preferably (1~10):(0.1~2), more preferably (3~7):(0.5~1.5), and even more preferably 5:1.

[0037] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0038] Unless otherwise specified, the following embodiments are all conventional methods.

[0039] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0040] Example 1 A broad-spectrum composition for resisting photodamage to the skin, comprising an active ingredient and excipients, wherein the active ingredient is 500 mg of 4-octylitaconic acid, and the excipients are 2.5 mL of polyethylene glycol 300 and 2.5 mL of PBS buffer, wherein the mass-volume concentration of 4-octylitaconic acid in the composition is 100 mg / mL.

[0041] The preparation method is as follows: Slowly add the measured polyethylene glycol 300 to the PBS buffer and stir thoroughly using a magnetic stirrer at a speed of 250 rpm for 8 minutes until the two excipients are completely mixed and a clear, transparent mixture is obtained.

[0042] The weighed 4-octylitaconic acid was gradually added to the above mixture, and stirring was continued at room temperature (20~25℃). The stirring speed was increased to 300 rpm, and the stirring time was 15 minutes, until the 4-octylitaconic acid was completely dissolved and the solution was clear and transparent. The solution was then filtered through a 0.22 μm filter membrane for sterilization to obtain the composition.

[0043] Example 2 A broad-spectrum composition for protecting against photodamage to the skin, comprising an active ingredient and excipients, wherein the active ingredient is 450 mg of 4-octylitaconic acid, and the excipients are 2 mL of polyethylene glycol 300 and 1 mL of PBS buffer, wherein the mass-volume concentration of 4-octylitaconic acid in the composition is 150 mg / mL.

[0044] The preparation method is as follows: Slowly add the measured polyethylene glycol 300 to the PBS buffer and stir thoroughly using a magnetic stirrer at a speed of 200 rpm for 10 minutes until the two excipients are completely mixed and a clear, transparent mixture is obtained.

[0045] The weighed 4-octylitaconic acid was gradually added to the above mixture, and stirring was continued at room temperature (20~25℃). The stirring speed was increased to 400 rpm, and the stirring time was 20 minutes, until the 4-octylitaconic acid was completely dissolved and the solution was clear and transparent. The solution was then filtered through a 0.22 μm filter membrane for sterilization to obtain the composition.

[0046] Example 3 A broad-spectrum composition for resisting photodamage to the skin, comprising an active ingredient and excipients, wherein the active ingredient is 22 mg of 4-octylitaconic acid, and the excipients are 1 mL of polyethylene glycol 300 and 1 mL of PBS buffer, wherein the mass-volume concentration of 4-octylitaconic acid in the composition is 11 mg / mL.

[0047] The preparation method is as follows: Slowly add the measured polyethylene glycol 300 to the PBS buffer and stir thoroughly using a magnetic stirrer at a speed of 300 rpm for 5 minutes until the two excipients are completely mixed and a clear, transparent mixture is obtained.

[0048] The weighed 4-octylitaconic acid was gradually added to the above mixture, and stirring was continued at room temperature (20~25℃). The stirring speed was increased to 380 rpm, and the stirring time was 15 minutes, until the 4-octylitaconic acid was completely dissolved and the solution was clear and transparent. The solution was then filtered through a 0.22 μm filter membrane for sterilization to obtain the composition.

[0049] Example 4 A broad-spectrum composition for resisting photodamage to the skin, comprising an active ingredient and excipients, wherein the active ingredient consists of 500 mg of 4-octyl itaconic acid and 100 mg of ginkgo biloba extract, and the excipients are 2.5 mL of polyethylene glycol 300 and 2.5 mL of PBS buffer. The composition contains 100 mg / mL of 4-octyl itaconic acid and 20 mg / mL of ginkgo biloba extract.

[0050] The preparation method is as follows: Slowly add the measured polyethylene glycol 300 to the PBS buffer and stir thoroughly using a magnetic stirrer at a speed of 250 rpm for 8 minutes until the two excipients are completely mixed and a clear, transparent mixture is obtained.

[0051] The weighed 4-octylitaconic acid and ginkgo biloba flavonoids were gradually added to the above mixture, and stirring was continued at room temperature (20~25℃). The stirring speed was increased to 300 rpm, and the stirring time was 15 minutes, until the 4-octylitaconic acid and ginkgo biloba flavonoids were completely dissolved and the solution was clear and transparent. The solution was then filtered through a 0.22 μm filter membrane for sterilization to obtain the composition.

[0052] Example 5 Effects of 4-Octylitaconic acid on UV-induced sunburn in mice 1. Laboratory animals: SPF-grade male C57 mice, 8 weeks old, weighing 22–24 g, were purchased from Shanghai Paijieluo Biotechnology Co., Ltd. All mice were housed at 23±2℃ with a 12-hour light / 12-hour dark cycle and free access to food and water. All animal experimental procedures complied with the requirements of the Laboratory Animal Ethics Committee.

[0053] 2. Model establishment and grouping for drug administration: All hair on the backs of the mice was shaved, covering an area of ​​approximately 4 × 4 cm. Before establishing the sunburn model, the mice were anesthetized with isoflurane and then placed in a UVB irradiation chamber at a wavelength of 312 nm and a concentration of 500 mJ / cm². 2 Intensive irradiation, once daily for two consecutive days, to establish a skin sunburn model.

[0054] The sunburn manifestations on the back skin of mice were observed daily after irradiation. Treatment was initiated on day 1 of UVB irradiation and continued for 7 days. The dosage of 4-octyl itaconic acid was 100 mg / kg / day, administered via intraperitoneal injection, with an injection volume of 0.2 mL / mouse / day.

[0055] The experimental groups are as follows: (1) Blank control group (control group): only hair was shaved, no UVB irradiation was performed, no solvents or drugs were injected, and the animals were fed normally for 7 days; (2) Model group (UV group): shaved and irradiated with UVB, without injection of any solvents or drugs, and fed normally for 7 days; (3) 4-Octylitaconic acid treatment group (UV+4OI group): The mice were shaved and irradiated with UVB. Starting from day 1, the combination obtained in Example 3 was injected intraperitoneally at a dose of 100 mg / kg / d (the concentration was 11 mg / mL, and the injection volume was 0.2 mL / mouse / day based on the average weight of mice of 22 g), and the treatment continued for 7 days.

[0056] 3. Experimental Methods and Results (1) Analysis of skin sunburn condition On day 1 and day 7 of treatment, photographs were taken of the skin on the backs of mice to observe erythema, edema, desquamation, and wound healing. The gross photographs taken on day 1 of treatment are shown below. Figure 1 As shown. By Figure 1 Gross photos of sunburned mice (day 1 of treatment) show that, compared with the model group, the erythema and edema on the back skin of mice in the 4-octyl itaconic acid treatment group were significantly reduced, and the damaged area was smaller, indicating that 4-octyl itaconic acid can rapidly relieve ultraviolet-induced sunburn in the early stage of treatment.

[0057] (2) HE staining of skin tissue Mice were sacrificed on day 1 and day 7 of treatment (n=3 per group at each time point), and skin specimens from the back were fixed in 4% neutral formaldehyde buffer for 24 h. Routine paraffin embedding, sectioning, and HE staining were performed. Skin tissue structure was observed under a digital section scanner to assess inflammatory cell infiltration and changes in epidermal thickness. Results are as follows: Figure 2 As shown. By Figure 2 HE staining results of the skin (days 1 and 7) showed that on day 1 of treatment, the epidermis of mice in the model group was significantly thickened, with acanthosis and extensive inflammatory cell infiltration; the inflammatory cell infiltration in the 4-octyl itaconic acid treatment group was significantly reduced, and the epidermal structure was relatively intact. On day 7 of treatment, epidermal proliferation disorder and chronic inflammation were still visible in the model group; while the epidermal structure of the 4-octyl itaconic acid treatment group was basically restored to normal, the inflammatory cell infiltration disappeared, and the dermal collagen was arranged regularly, further confirming that 4-octyl itaconic acid has good anti-inflammatory and repair-promoting effects.

[0058] (3) HE staining of heart, liver, spleen, lung and kidney tissues Mice were sacrificed on day 7 of treatment, and the heart, liver, spleen, lungs, and kidneys were removed and fixed in 4% neutral formaldehyde buffer for 24 h. After routine paraffin embedding, sectioning, and HE staining, the tissue structures of each organ were observed using a digital section scanner to assess the in vivo safety of 4-octyl itaconic acid. Results are as follows: Figure 3 As shown. By Figure 3 HE staining results of the heart, liver, spleen, lungs, and kidneys (on day 7 of treatment) showed that there were no significant differences in the tissue structure of each organ in the 4-octyl itaconic acid treatment group compared with the blank control group. No cell degeneration, necrosis, or inflammatory infiltration was observed, indicating that 4-octyl itaconic acid had no obvious systemic toxic side effects on the major organs of mice at the dose in this experiment and had good biosafety.

[0059] (4) KRT14 immunofluorescence staining Mice were sacrificed on day 7 of treatment. Skin specimens from the back were fixed, routinely embedded in paraffin, sectioned, and subjected to KRT14 immunofluorescence staining. The expression of KRT14 in the basal and spinous layers of the epidermis was observed under a fluorescence microscope to assess the epidermal barrier repair effect. Results are as follows: Figure 4 As shown.

[0060] Depend on Figure 4 The KRT14 immunofluorescence staining results (day 7 of treatment) showed that the KRT14 fluorescence signal in the epidermis of the model group mice was significantly weakened and its distribution was disordered, indicating that ultraviolet radiation damaged the epidermal barrier function; while the KRT14 fluorescence signal in the 4-octylitaconic acid treatment group was significantly enhanced, and the positive staining was continuously distributed in the basal layer and spinous layer, close to the level of the blank control group, indicating that 4-octylitaconic acid can effectively restore the epidermal barrier function after ultraviolet damage.

[0061] Example 6 Effects of 4-Octylitaconic acid on UV-induced photoaging of mouse skin 1. Laboratory animals SPF-grade male SKH-1 hairless mice, 8 weeks old, weighing 22–24 g, were purchased from the Shanghai Public Health Clinical Center. All mice were housed at 23±2℃ under a 12-hour light / 12-hour dark cycle with free access to food and water. All animal experimental procedures complied with the requirements of the Laboratory Animal Ethics Committee.

[0062] 2. Model establishment and grouped drug administration Before establishing the photoaging model, mice were anesthetized with isoflurane and then placed in a UVB irradiation chamber for irradiation at a wavelength of 312 nm. The irradiation frequency was 5 times per week for 8 consecutive weeks, with the irradiation time increasing week by week: 1 min / session in weeks 1 and 2, 1 min 10 s / session in weeks 3 and 4, 1 min 20 s / session in weeks 5 and 6, and 1 min 30 s / session in weeks 7 and 8, thus establishing the skin photoaging model.

[0063] After irradiation, mice were observed to exhibit photoaging symptoms such as wrinkles, roughness, and decreased elasticity on their back skin. Treatment began on day 1 after model establishment and continued for two weeks. The dosage of 4-octyl itaconic acid was 100 mg / kg / day, administered via intraperitoneal injection at a volume of 0.2 mL / mouse / day.

[0064] The experimental groups are as follows: (1) Blank control group: No UVB irradiation, no injection of any solvents or drugs, and normal feeding; (2) Model group (UV, Photoaged): Irradiated with UVB, without injection of any solvents or drugs, and raised normally; (3) Solvent control group (UV_Vehicle, Photoaged+Vehicle): Irradiated with UVB, and after the modeling was completed, an equal volume of solvent was injected into the peritoneum daily (the solvent referred to here is a mixture of 1 mL polyethylene glycol 300 and 1 mL PBS buffer, 0.2 mL / animal / day) for 2 consecutive weeks; (4) 4-Octylitaconic acid treatment group (UV_4OI, Photoaged+4OI): UVB irradiation, and intraperitoneal injection of the composition obtained in Example 3 at a dose of 100 mg / kg / d (the concentration was 11 mg / mL, and the injection volume was 0.2 mL / mouse / day based on the average weight of mice of 22 g), for 2 consecutive weeks.

[0065] (5) 4-Octyl itaconic acid combined with ginkgo biloba extract treatment group (UV_4OI_GK): UVB irradiation, and intraperitoneal injection of the composition obtained in Example 4 at a dose of 100 mg / kg / d (the concentration was 11 mg / mL, and the injection volume was 0.2 mL / mouse / day based on the average weight of mice of 22 g), for 2 consecutive weeks.

[0066] 3. Experimental Methods and Results (1) Analysis of skin photoaging status like Figure 5As shown, after UV-induced modeling, the skin on the backs of mice in the model group exhibited obvious deep wrinkles and rough skin texture. Compared with the model group, the number of wrinkles on the backs of mice treated with 4-octyl itaconic acid monotherapy was significantly reduced, the wrinkle depth was significantly shallower, and the skin surface tended to be smoother, indicating that 4-octyl itaconic acid can effectively alleviate UV-induced photoaging damage. Notably, the efficacy of the combination therapy of 4-octyl itaconic acid and ginkgo biloba extract was more significant, with a greater reduction in skin wrinkles than the monotherapy group, and the skin appearance approaching that of the normal control group, suggesting that the combination of the two drugs may have a synergistic anti-photoaging effect.

[0067] (2) Detection of epidermal water loss and stratum corneum moisture content Two weeks after treatment, the stratum corneum water content and transepidermal water loss of the dorsal skin of mice in each group were measured using a skin moisture meter and a transepidermal water loss meter to assess epidermal barrier function. The results are as follows: Figure 6 As shown.

[0068] Depend on Figure 6 The results of transepidermal water loss and stratum corneum water content measurements (after 2 weeks of treatment) showed that, compared with the model group, the transepidermal water loss of the back skin of mice treated with 4-octyl itaconic acid was significantly reduced and the stratum corneum water content was significantly increased, indicating that 4-octyl itaconic acid can effectively improve UV-induced epidermal barrier function damage.

[0069] (3) HE staining of skin tissue Two weeks after treatment, mice were sacrificed, and skin specimens from their backs were fixed in 4% neutral formaldehyde buffer for 24 hours. Routine paraffin embedding, sectioning, and HE staining were performed. Skin tissue structure was observed under a digital section scanner to assess stratum corneum thickness and inflammatory cell infiltration. Results are as follows: Figure 7 As shown.

[0070] Depend on Figure 7 HE staining results of the skin (after 2 weeks of treatment) showed that the stratum corneum of the model group mice was significantly thickened, the stratum spinosum was thickened, and a large number of inflammatory cells were infiltrated; while the stratum corneum thickness of the 4-octyl itaconic acid treatment group was close to that of the blank control group, the inflammatory cell infiltration was significantly reduced, and the epidermal structure tended to be normal, indicating that 4-octyl itaconic acid can improve the abnormal proliferation of the stratum corneum and inflammatory infiltration of photoaged skin.

[0071] (4) Masson staining Two weeks after treatment, mice were sacrificed, and skin specimens from their backs were fixed, routinely embedded in paraffin, sectioned, and stained with Masson's stain. The arrangement and distribution of collagen fibers in the dermis were observed using a digital section scanner to assess the degree of collagen fiber breakage and structural disorder. The results are as follows: Figure 8 As shown.

[0072] Depend on Figure 8Masson staining results (after 2 weeks of treatment) showed that collagen fibers in the dermal layer of the back skin of mice in the model group were significantly broken, disordered, and decreased in density; while collagen fibers in the 4-octyl itaconic acid treatment group were more regularly arranged, with fewer breaks and increased density than those in the model group, indicating that 4-octyl itaconic acid can effectively reverse UV-induced collagen degradation and structural damage.

[0073] (5) Weight monitoring During the treatment period, the body weight of mice in each group was measured and recorded weekly to observe the effect of 4-octylitaconic acid on the weight gain of mice. The results are as follows: Figure 9 As shown.

[0074] Depend on Figure 9 The weight change curves (after 2 weeks of treatment) showed that the weight of mice in the blank control group, solvent control group, and 4-octylitaconic acid treatment group all showed a steady increase throughout the experimental period. There were no significant differences in weight among the groups at any time point (p>0.05), indicating that 4-octylitaconic acid had no significant adverse effects on the mice's food intake, metabolism, and overall health during the 2-week treatment period, further verifying its safety for long-term prevention and treatment of photoaging.

[0075] (6) Transcriptomics GO enrichment analysis Two weeks after treatment, mice were sacrificed, and total RNA was extracted from the dorsal skin tissue of each group for transcriptome sequencing. Differentially expressed genes were screened using |log2FC|≥1 and p<0.05 as the threshold. GO functional enrichment analysis was performed on downregulated differentially expressed genes in the 4-octylitaconic acid treatment group compared to the model group to explore the potential molecular mechanism by which 4-octylitaconic acid improves photoaging. The results are as follows: Figure 10 As shown.

[0076] Depend on Figure 10GO enrichment analysis revealed that, compared to the model group, the differentially expressed genes downregulated in the 4-octyl itaconic acid treatment group were significantly enriched in multiple inflammation and immune-related pathways, including biological processes such as antigen processing and presentation, chemokine-mediated signaling pathway, immune response, inflammatory response, and neutrophil chemotaxis, as well as molecular functions such as cytokine activity, chemokine activity, Toll-like receptor 4 binding, and RAGE receptor binding. These results indicate that 4-octyl itaconic acid can significantly downregulate the expression of inflammation-related pathways in photoaged skin at the transcriptional level, thereby exerting its anti-photoaging effect.

[0077] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A broad-spectrum composition for resisting photodamage to the skin, characterized in that, It includes an active ingredient and excipients, wherein the active ingredient includes 4-octylitaconic acid, and the excipients include polyethylene glycol 300 and PBS buffer.

2. The composition according to claim 1, characterized in that, The mass-volume concentration of 4-octylitaconic acid in the composition is 5~150 mg / mL; the volume ratio of polyethylene glycol 300 to PBS buffer is (0.5~2):

1.

3. The composition according to claim 1, characterized in that, The active ingredients also include ginkgo biflavonoids.

4. The composition according to claim 3, characterized in that, The mass ratio of 4-octyl itaconic acid to ginkgo biflavonoids is (1~10):(0.1~2).

5. A method for preparing the composition according to any one of claims 1 to 4, characterized in that, The process includes the following steps: mixing the excipients and then mixing them with the active ingredient to obtain the composition.

6. The preparation method according to claim 5, characterized in that, It also includes a storage step, wherein the storage is to freeze the composition at -80°C or below in the dark.

7. The use of the composition according to any one of claims 1 to 4 in the preparation of a broad-spectrum anti-skin photodamage and / or anti-skin photoaging product. Application of 8,4-Octylate itaconic acid in the preparation of broad-spectrum anti-photodamage and / or anti-photoaging products. Application of 9,4-octyl itaconic acid and ginkgo biflavonoids in the preparation of broad-spectrum anti-photodamage and / or anti-photoaging products.

10. The application according to claim 9, characterized in that, The mass ratio of 4-octyl itaconic acid to ginkgo biflavonoids is (1~10):(0.1~2).

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