Drying method of chuanxiong medicinal material and use of chuanxiong or extract thereof in preparation of external medicine for treating atopic dermatitis

Abstract

The application provides a drying method of Chuanxiong medicinal material and application of Chuanxiong or its extract in preparation of an external medicine for treating atopic dermatitis. The drying method of Chuanxiong medicinal material improves Chuanxiong processing efficiency, shortens processing period, obtains by-product Chuanxiong extract in addition to preparation of decoction pieces, reduces energy consumption and lowers production cost. The Chuanxiong essential oil and Chuanxiong extract are both composed of small molecule components, have good affinity to skin, are absorbed through skin quickly, can quickly relieve symptoms such as itching and skin damage caused by atopic dermatitis, and are natural, safe and free of side effects. Meanwhile, the small molecule components contained in the Chuanxiong essential oil and Chuanxiong extract have good lipophilicity, have softening effect on the thickened stratum corneum caused by atopic dermatitis, and are more conducive to drug absorption. In addition, the Chuanxiong essential oil and Chuanxiong extract are simple to prepare and low in price.

Description

Technical Field

[0001] This invention relates to the use of Ligusticum chuanxiong or its extracts in the preparation of topical medicines for treating atopic dermatitis. Background Technology

[0002] Chuanxiong (Ligusticum chuanxiong Hort.), a plant of the Apiaceae family, is a traditional Chinese medicine with a long history of medicinal use. It is warm in nature, pungent and slightly bitter in taste, and enters the liver, gallbladder, and pericardium meridians. Its functions include promoting blood circulation and qi flow, dispelling wind and relieving pain. It is used for chest pain, stabbing pain in the chest and hypochondrium, swelling and pain from falls, irregular menstruation, amenorrhea and dysmenorrhea, abdominal masses and pain, headache, and rheumatic pain. Prepared medicinal herbs are one of the basic forms of clinical medication in traditional Chinese medicine. They are not only important raw materials for prepared Chinese medicines but also a key link in the development of the entire Chinese medicine industry. Therefore, the quality of prepared medicinal herbs directly affects clinical efficacy. In recent years, the state has strengthened the management of the quality of prepared medicinal herbs, but problems such as insufficient content of effective ingredients still frequently occur, mainly related to improper soaking time of the herbs, non-standard processing at the place of origin, and non-standard processing of the prepared herbs. To ensure the quality of Chinese medicinal herbs and address issues such as overlapping processing, cumbersome procedures, and lack of quantifiable indicators, some scholars have proposed the concept of integrated processing of Chinese medicinal herbs at their place of origin and preparation of medicinal herbs (hereinafter referred to as "integration").

[0003] Currently, the 2020 edition of the Chinese Pharmacopoeia describes the processing of Ligusticum chuanxiong as both raw material and processed medicinal slices. The raw material is harvested in summer when the nodes on the stem are prominent and slightly purplish. The mud and sand are removed, and the herbs are dried in the sun and then the fibrous roots are removed. The processing of the processed medicinal slices is specified as follows: "Remove impurities, separate by size, wash, moisten thoroughly, cut into thick slices, and dry."

[0004] Traditional processing methods at the place of origin cause the following problems: (1) Traditional processing technology requires one water treatment and two drying processes from fresh herbs to processed herbs, making the processing procedure complicated; (2) Processing relies on personal experience, which increases the error caused by human factors; (3) The processing time is long, and it is difficult to standardize and quantify the processing process; (4) The excessively long production cycle is prone to loss of effective components, which reduces the efficacy of the processed herbs. Therefore, in order to address the above defects, this invention provides a method for processing Ligusticum chuanxiong using microwave vacuum drying technology.

[0005] The main effects and functions of Ligusticum chuanxiong include the following: 1. Promoting blood circulation and removing blood stasis: Ligusticum chuanxiong is rich in volatile oils and active ingredients such as ligustrazine, which can promote blood circulation, improve microcirculation disorders, prevent thrombosis, and relieve pain caused by blood stasis. 2. Relaxing muscles and tendons: Ligusticum chuanxiong has a certain regulating effect on muscles and tendons, which can relieve tension and stiffness of muscles and tendons, promote the flexibility and mobility of muscles and tendons, and help relieve muscle pain and joint discomfort. 3. Relieving pain: Ligusticum chuanxiong can improve local blood circulation and reduce blood stasis through its blood-activating and stasis-removing effects, thereby alleviating pain symptoms. In addition, external application of Ligusticum chuanxiong has anti-inflammatory effects, which can promote wound healing and improve blood circulation. Furthermore, there are reports that external application of Ligusticum chuanxiong can promote blood circulation and remove blood stasis, and can be used to treat some skin diseases, such as urticaria and eczema. Because Ligusticum chuanxiong contains volatile oils, alkaloids, organic acids, phenolic acids, polysaccharides, as well as compounds such as 5-hydroxymethylfurfural and dibutyl phthalate, and components such as 6-hydroxymethyl-3-hydroxypyridine and nicotinic acid.

[0006] Atopic dermatitis (AD) is a chronic, relapsing, inflammatory skin disease with a genetic predisposition and is usually closely related to allergic factors. Typical symptoms of atopic dermatitis include: Dry skin: Patients often experience dry skin, especially during the acute phase. Itching: Patients experience intense itching, which is one of the main symptoms of atopic dermatitis. Papules: White papules may appear on the skin after slight irritation, especially on the extremities. Erosion and hypertrophy: The skin may exhibit erosion, exudation, desquamation, and crusting; in severe cases, hypertrophy may also occur. Polymorphic lesions: The lesions of atopic dermatitis can be polymorphic, including erythema, papules, and vesicles. Exudative tendency: The skin lesions of atopic dermatitis have an exudative tendency, especially during the acute phase. Complications: Severe cases may develop complications such as asthma, allergic colitis, allergic rhinitis, and allergic conjunctivitis.

[0007] Treatment methods for atopic dermatitis include: Topical moisturizing creams: to keep the skin hydrated and relieve dryness. Topical medications: for mild symptoms, desonide cream or zinc oxide ointment can be used. In the acute phase without exudation, zinc oxide ointment can be used; for excessive exudation, wet compresses with 3% boric acid solution can be used. After exudation decreases, corticosteroid creams, such as hydrocortisone butyrate ointment or halometasone cream, can be used, often in combination with antibiotic ointments. Systemic medications: oral antihistamines and non-macrocellular membrane stabilizers, such as ketotifen and cetirizine, to relieve itching, erythema, and congestion. Physical therapy: narrow-band UVB irradiation has a good effect on atopic dermatitis. Immunotherapy: different drugs are selected according to the severity and onset of the condition, such as corticosteroids, cyclosporine, thymopentin, and interferon. Desensitization therapy: desensitization treatment is performed based on the results of intradermal allergen testing.

[0008] Eczema and atopic dermatitis (AD) are two distinct skin conditions. Eczema is a broader term encompassing various types of inflammatory skin diseases, characterized by symptoms such as redness, itching, and blisters. Atopic dermatitis, on the other hand, is a chronic inflammatory skin disease with a genetic predisposition, often associated with an allergic constitution, and manifests as dry skin, intense itching, and polymorphic skin lesions. Atopic dermatitis is closely related to a genetic predisposition to allergies; patients often have a family history of allergies, and its onset is associated with abnormal skin barrier function and immune dysregulation. The pathogenesis of eczema is relatively complex and can be triggered by various internal and external factors, including contact with allergens and chemical irritants. Genetic factors are not as prominent as in atopic dermatitis. Atopic dermatitis typically has specific predilection sites, such as the flexural areas of the elbows, knees, and neck. The skin is markedly dry, often accompanied by intense itching, and the rash often presents as lichenification. Eczema can occur anywhere on the body; in the acute phase, it is characterized by erythema, papules, and vesicles with a tendency to ooze, while in the chronic phase, it is characterized by thickened and rough skin. Atopic dermatitis primarily affects children, especially infants, and in some patients, the condition may persist into adulthood. Eczema can occur at any age, and the clinical manifestations may differ across age groups.

[0009] There are no literature reports on which components of Ligusticum chuanxiong have therapeutic effects on atopic dermatitis when applied topically. Summary of the Invention

[0010] The technical solution of this invention is to provide a method for drying Ligusticum chuanxiong; this invention also provides new uses for Ligusticum chuanxiong or its extracts.

[0011] This invention provides a method for drying Ligusticum chuanxiong, which uses microwave vacuum drying to dry fresh Ligusticum chuanxiong.

[0012] Specifically, it includes the following steps: Take fresh Ligusticum chuanxiong, remove impurities and non-medicinal parts, rinse quickly, place in a cool and ventilated place, air dry, slice, microwave vacuum dry at 50℃ for 2-3 hours, sift out the debris, and you will get the product.

[0013] Preferably, the slices are 2-7 cm in diameter and 2-6 mm in thickness; the drying time is 2 hours.

[0014] The present invention also provides the use of Ligusticum chuanxiong or its extracts in the preparation of topical medicines for treating atopic dermatitis.

[0015] The drug mentioned is one that has an antipruritic effect.

[0016] The chuanxiong extract mentioned above is chuanxiong essential oil or chuanxiong extract.

[0017] The Chuanxiong dew mentioned above is a byproduct obtained by drying fresh Chuanxiong using the aforementioned Chuanxiong medicinal material drying method and passing it through a condensation device.

[0018] The aforementioned topical drug preparations include: gels, ointments, emulsions, ointments, sprays, aerosols, lotions, rinses, liniments, coatings, and film-forming agents.

[0019] This invention provides a method for drying Ligusticum chuanxiong (Chuanxiong) medicinal materials, which improves processing efficiency and shortens the processing cycle; in addition to preparing medicinal slices, it also yields the byproduct Ligusticum chuanxiong extract; reducing energy consumption and lowering production costs. The Ligusticum chuanxiong essential oil and Ligusticum chuanxiong extract of this invention are both composed of small-molecule components. Due to their good affinity for the skin, they are rapidly absorbed through the skin and can quickly relieve symptoms such as itching and skin lesions caused by atopic dermatitis. Furthermore, the ingredients are natural, safe, and have no side effects. Simultaneously, the small-molecule components in Ligusticum chuanxiong essential oil and Ligusticum chuanxiong extract have good lipophilicity, softening the thickened stratum corneum caused by atopic dermatitis, thus facilitating drug absorption. Moreover, the preparation of Ligusticum chuanxiong volatile oil and Ligusticum chuanxiong extract is simple and inexpensive. Attached Figure Description

[0020] Figure 1 Different characteristics of Ligusticum striatum slices (Note: A: Low-temperature dried Ligusticum striatum slices; B: Processed Ligusticum striatum slices from the place of origin; C: Vacuum dried Ligusticum striatum slices; D: Microwave vacuum dried Ligusticum striatum slices). Detailed Implementation

[0021] Example 1: Preparation of Ligusticum chuanxiong essential oil according to the present invention

[0022] Take sliced ​​Ligusticum chuanxiong, pulverize it, and pass it through a No. 4 sieve. Weigh approximately 500g of the powder and place it in a flask. Add an appropriate amount of distilled water at a ratio of 1:6 (sliced ​​herbs: water, w / v) and soak for 30 minutes. Connect the volatile oil extractor and the reflux condenser, and reflux extract until the oil volume in the extractor no longer increases, then stop heating. Slowly drain the water layer, retaining the upper oil layer, to obtain the volatile oil of Ligusticum chuanxiong (Ligusticum chuanxiong essential oil).

[0023] Example 2: Preparation of Chuanxiong Decoction of the Present Invention

[0024] Fresh Ligusticum chuanxiong is taken by microwave vacuum drying integrated process. After removing impurities and non-medicinal parts, it is quickly rinsed, placed in a cool and ventilated place, air-dried, sliced ​​(about 2 mm thick), and microwave vacuum dried at 50℃ for 2-3 hours. After sieving out the debris, the dried Ligusticum chuanxiong medicinal material is obtained. The by-product Ligusticum chuanxiong dew generated during the processing is collected by condensation device.

[0025] Example 3: Drying method of the medicinal material Ligusticum chuanxiong according to the present invention

[0026] Take fresh Ligusticum chuanxiong, remove impurities and non-medicinal parts, rinse quickly, place in a cool and ventilated place, air dry, slice (about 2 mm thick), microwave vacuum dry at 50℃ for 2-3 hours, sift out the debris, and you have the product.

[0027] Example 4: Comparison of the present invention's method for drying Ligusticum striatum with traditional Ligusticum striatum processing and modern Ligusticum striatum drying methods.

[0028] 1. Preparation of medicinal slices using different processing methods

[0029] Traditionally, 10 kg of fresh Ligusticum chuanxiong is taken, impurities and non-medicinal parts are removed, and the herbs are placed in a cool, ventilated place to air-dry, thus obtaining Ligusticum chuanxiong medicinal material. The above-mentioned Ligusticum chuanxiong medicinal material is quickly rinsed to remove impurities such as mud and sand, moistened with water until thoroughly soaked, sliced ​​(about 2-4 mm thick), dried, and sieved to remove debris, thus obtaining the final product.

[0030] The low-temperature drying integrated medicinal slices are prepared by taking 10 kg of fresh Ligusticum chuanxiong, removing impurities and non-medicinal parts, quickly rinsing, placing in a cool and ventilated place, air-drying, slicing (about 2 mm thick), drying in a forced-air dryer at 50℃ for 12 hours, and sieving out the debris.

[0031] The vacuum-dried integrated medicinal slices are prepared by taking 10 kg of fresh Ligusticum chuanxiong, removing impurities and non-medicinal parts, quickly rinsing, placing in a cool and ventilated place, air-drying, slicing (about 2 mm thick), vacuum drying at 50℃ for 8 hours, and sieving out the debris.

[0032] Take 10 kg of fresh Ligusticum chuanxiong, remove impurities and non-medicinal parts, rinse quickly, place in a cool and ventilated place, air dry, slice (about 2 mm thick), microwave vacuum dry at 50℃ for 2 hours, and sieve out the debris to obtain the product.

[0033] 2. Appearance Evaluation Methods

[0034] The morphological evaluation criteria for low-temperature dried Ligusticum striatum slices, locally processed Ligusticum striatum slices, vacuum-dried Ligusticum striatum slices, and microwave vacuum-dried Ligusticum striatum slices were based on the color and odor of the Ligusticum striatum slices, as shown in Table 1. Figure 1 .

[0035] Table 1. Evaluation criteria for the properties of Ligusticum chuanxiong prepared by microwave vacuum processing.

[0036]

[0037]

[0038] 3. Methods for determining volatile oil content

[0039] The determination of volatile oils was performed according to Method A under the General Chapter 2204 of the 2020 edition of the Chinese Pharmacopoeia. The specific method is as follows: This method is applicable to the determination of volatile oils with a relative density below 1.0. Take 500g of the test sample (equivalent to containing 0.5–1.0ml of volatile oil), weigh it (accurate to 0.01g), place it in a flask, add 3000ml of water (or an appropriate amount) and a few glass beads, shake to mix, and connect the volatile oil analyzer to the reflux condenser. Add water from the top of the condenser until it fills the graduated section of the volatile oil analyzer and overflows into the flask. Place the flask in a heating mantle and slowly heat to boiling, maintaining a gentle boil for about 5 hours, until the oil level in the analyzer no longer increases. Stop heating, let it stand for a moment, and then open the stopcock at the bottom of the analyzer to slowly release the water until the upper part of the oil layer reaches 5mm above the 0 mark. After standing for more than 1 hour, open the piston to lower the oil layer until its top is level with the 0 mark on the scale. Read the amount of volatile oil and calculate the content (%) of volatile oil in the sample.

[0040] 4. Method for determining ferulic acid content

[0041] The determination was performed according to the high performance liquid chromatography (General Rule 0512) method in the 2020 edition of the Chinese Pharmacopoeia. The specific method was as follows: octadecylsilane-bonded silica gel was used as the stationary phase; methanol-0.5% acetic acid solution was used as the mobile phase; and the detection wavelength was 285 nm. The theoretical plate number, calculated based on the ferulic acid peak, should be no less than 4000.

[0042] Preparation of the reference solution: Weigh an appropriate amount of ferulic acid reference standard accurately, place it in a brown volumetric flask, and add 70% methanol to prepare a solution containing 200 μg per ml.

[0043] Preparation of the test solution: Take about 1g of the powder of this product (passed through a No. 4 sieve), accurately weigh it, place it in a stoppered conical flask, accurately add 40ml of 70% methanol, stopper tightly, weigh it, heat and sonicate for 30 minutes, cool it, weigh it again, make up the weight loss with 70% methanol, shake well, let it stand, take the supernatant, filter it, and take the filtrate to obtain the test solution.

[0044] The assay involves precisely pipetting 10 μl each of the reference solution and the test solution into a liquid chromatograph and measuring the results.

[0045] 5. Evaluation Methods

[0046] When examining the Ligusticum chuanxiong samples treated with different indicators, the indicators influenced each other. Therefore, a comprehensive score was calculated. The Hassan method was used to normalize the overall desirability (OD) of the five selected indicators, standardizing the results to a "normalized value" (OD) between 0 and 1. Regardless of whether the original indicator was better the higher or lower it was, a higher OD value after processing was better, directly reflecting the merits of each experimental method. In this experiment, higher scores for morphological properties, volatile oil content, ferulic acid content, and yield were preferred, calculated using the formula: di = (Yi - Ymin) / (Ymax - Ymin); shorter processing time was preferred, calculated using the formula: di = (Ymax - Yi) / (Ymax - Ymin), where Ymin is the minimum value among the indicators, and Ymax is the maximum value. Based on literature, the comprehensive score calculation formula is: Total Score = % × d 性状 +15%×d 挥发油含量 +15%×d 阿魏酸含量 +40%×d 加工时间 +15%×d 收率 The results showed that the quality of Ligusticum chuanxiong produced by microwave vacuum drying was significantly better than that produced by the other three processes, and the processing time was shortened by 6 to 24 times compared to the other three processes.

[0047] Table 2. Results of various indicators of Ligusticum chuanxiong processed by different methods.

[0048]

[0049] The following pharmacodynamic tests demonstrate the beneficial effects of this invention.

[0050] Experiment 1: Treatment of Acute Pruritus Model Mice with Chuanxiong Essential Oil Ointment

[0051] Based on the pruritus induced in the model, dermatophyte-related acute pruritus can be classified into two types: histamine-dependent and non-histamine-dependent. Histamine phosphate is a commonly used histamine-dependent pruritus induced by histamine, while non-histamine-dependent pruritus induced by histamine mainly includes chloroquine, serotonin, and LP44. Based on the above-mentioned pruritus induced acute pruritus mouse model, from a behavioral perspective, the pharmacodynamic effects of Ligusticum chuanxiong essential oil (prepared according to Example 1) in treating different pruritus induced acute pruritus mouse models were investigated.

[0052] 1. Experimental study on the treatment of chloroquine-induced acute pruritus model mice with Ligusticum chuanxiong essential oil ointment

[0053] Based on a chloroquine-induced acute pruritus model in mice, this study investigated the pharmacodynamic effects of Ligusticum chuanxiong essential oil ointment on acute pruritus in mice from a behavioral perspective.

[0054] (1) Establishment of a histamine-induced acute pruritus model in mice

[0055] Five-week-old male ICR mice were acclimatized for one week and then randomly divided into five groups: a blank control group, a chloroquine group, a low-dose chloroquine + 0.5% essential oil group, a medium-dose chloroquine + 1% essential oil group, and a high-dose chloroquine + 2% essential oil group, with eight mice in each group. The hair on the right side of the neck and back of the mice was shaved, with a shaving area of ​​1cm × 2cm.

[0056] (2) Preparation method of essential oil ointment

[0057] White petrolatum is heated in a 55°C water bath and stirred until melted. After adding Ligusticum chuanxiong essential oil, it is stirred evenly until it cools and becomes an essential oil ointment with concentrations of 0.5%, 1%, and 2%, which means that each 100g ointment contains 0.5mL, 1mL, and 2mL of Ligusticum chuanxiong essential oil, respectively.

[0058] (3) Administration

[0059] Inducing itching, mice were injected intradermally with 50 μL of chloroquine solution (4 mg / mL) at the hair removal site on the nape of their necks. Except for the blank control group and the model group, which were treated with 100 mg of petroleum jelly, the other groups were given 100 mg of the corresponding ointment at the hair removal site. Immediately after application, the mice were placed in an observation box, and their behavior was recorded on video for 30 minutes under undisturbed conditions.

[0060] After the video recording was completed, it was saved for later review to record the mice's scratching behavior. The scratching behavior of the mice was counted. One scratch was defined as the mouse raising its hind paw to scratch the injection site once or more until the hind paw touched the ground or the mouse retracted its paw and paused. The number of scratches by mice in different groups was statistically analyzed.

[0061] (4) Experimental Results

[0062] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group mice was significantly increased (P < 0.05), indicating successful model establishment. Compared with the model group, there was no significant difference in the low-dose essential oil group, which had no significant effect on chloroquine-induced itching in mice. The low-dose essential oil group significantly reduced the number of scratches (P < 0.5), the medium-dose essential oil group significantly reduced the number of scratches (P < 0.01), and the high-dose essential oil group also significantly reduced the number of scratches (P < 0.01), indicating that both 1% and 2% concentrations of essential oil ointment had a significant effect on improving chloroquine-induced acute itching in mice.

[0063] Table 3. Acute itching and scratching in mice treated with essential oil ointment and chloroquine.

[0064] Blank control group 25.38±9.93 Chloroquine + Vaseline group <![CDATA[93.00±33.65 ## ]]> Chloroquine + essential oil low-dose group <![CDATA[54.88±17.76 * ]]> Chloroquine + essential oil medium dose group <![CDATA[11.00±4.31 ** ]]> Chloroquine + High-dose essential oil group <![CDATA[13.88±4.87 ** ]]>

[0065] (Experimental data are expressed as mean ± SEM. * indicates a significant difference between each drug administration group and the model group, *p<0.5, **p<0.01, # indicates a significant difference between the model group and the blank control group, ##p<0.05.)

[0066] 2. Experimental study on the treatment of LP44-induced acute pruritus model mice with Ligusticum chuanxiong essential oil ointment

[0067] Based on the LP44-induced acute pruritus model in mice, this study explores the pharmacodynamic effects of Ligusticum chuanxiong essential oil ointment on acute pruritus in mice from a behavioral perspective.

[0068] (1) Establishment of LP44-induced acute pruritus model in mice

[0069] Five-week-old male ICR mice were acclimatized for one week and then randomly divided into five groups: a blank control group, an LP44 group, a low-dose LP44 + 0.5% essential oil group, a medium-dose LP44 + 1% essential oil group, and a high-dose LP44 + 2% essential oil group, with eight mice in each group. The hair on the right side of the neck and back of the mice was shaved, with a shaving area of ​​1cm × 2cm.

[0070] (2) Preparation method of essential oil ointment

[0071] White petrolatum is heated in a 55°C water bath and stirred until melted. After adding Ligusticum chuanxiong essential oil, it is stirred evenly until it cools and becomes an essential oil ointment with concentrations of 0.5%, 1%, and 2%, which means that each 100g ointment contains 0.5mL, 1mL, and 2mL of Ligusticum chuanxiong essential oil, respectively.

[0072] (3) Administration

[0073] Inducing itching, mice were injected intradermally with 50 μL of LP44 solution (0.003 mg / mL) at the hair removal site on the nape of their necks. Except for the blank control group and the model group, which were treated with 100 mg of petroleum jelly, the other groups were given 100 mg of the corresponding ointment at the hair removal site. Immediately after application, the mice were placed in an observation box, and their behavior was recorded on video for 30 minutes under undisturbed conditions.

[0074] After the video recording was completed, it was saved for later review to record the mice's scratching behavior. The scratching behavior of the mice was counted. One scratch was defined as the mouse raising its hind paw to scratch the injection site once or more until the hind paw touched the ground or the mouse retracted its paw and paused. The number of scratches by mice in different groups was statistically analyzed.

[0075] (4) Experimental Results

[0076] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group mice was significantly increased (P < 0.05), indicating successful model establishment. Compared with the model group, there was no significant difference in the low-dose essential oil group, which had no significant effect on LP44-induced itching in mice. The medium-dose essential oil group significantly reduced the number of scratches (P < 0.01), and the high-dose essential oil group also significantly reduced the number of scratches (P < 0.01), indicating that both 1% and 2% concentrations of essential oil ointment had a significant effect on improving LP44-induced acute itching in mice.

[0077] Table 4. Acute itching and scratching in LP44 mice treated with essential oil ointment.

[0078] Blank control group 25.38±9.93 LP44 + Vaseline group <![CDATA[90±17.51 ## ]]> LP44+ essential oil low-dose group 79.5±18.76 LP44+ essential oil medium dose group <![CDATA[34.5±6.52 ** <!-- 6 -->]]> LP44+ High-dose essential oil group <![CDATA[17.75±5.11 ** ]]>

[0079] (Experimental data are expressed as mean ± SEM. * indicates a significant difference between each drug administration group and the model group, *p<0.5, **p<0.01, # indicates a significant difference between the model group and the blank control group, ##p<0.05.)

[0080] 3. Experimental study on the treatment of serotonin-induced acute pruritus model mice with Ligusticum chuanxiong essential oil ointment

[0081] Based on a serotonin-induced acute pruritus model in mice, this study investigates the pharmacodynamic effects of Ligusticum chuanxiong essential oil ointment on acute pruritus in mice from a behavioral perspective.

[0082] (1) Establishment of a serotonin-induced acute pruritus model in mice

[0083] Five-week-old male ICR mice were acclimatized for one week and then randomly divided into five groups: a blank control group, a serotonin group, a low-dose serotonin + 0.5% essential oil group, a medium-dose serotonin + 1% essential oil group, and a high-dose serotonin + 2% essential oil group, with eight mice in each group. The hair on the right side of the neck and back of the mice was shaved, with a shaving area of ​​1cm × 2cm.

[0084] (2) Preparation method of essential oil ointment

[0085] White petrolatum was heated in a 55°C water bath and stirred until melted. After adding chuanxiong essential oil, it was stirred evenly until it cooled and solidified into essential oil ointments with concentrations of 0.5%, 1%, and 2%.

[0086] (3) Administration

[0087] Inducing itching, mice were injected intradermally with 50 μL of serotonin solution (0.003 mg / mL) at the hair removal site on the nape of their necks. Except for the blank control group and the model group, which were treated with 100 mg of petroleum jelly, the other groups were given 100 mg of the corresponding ointment at the hair removal site. Immediately after application, the mice were placed in an observation box, and their behavior was recorded on video for 30 minutes under undisturbed conditions.

[0088] After the video recording was completed, it was saved for later review to record the mice's scratching behavior. The scratching behavior of the mice was counted. One scratch was defined as the mouse raising its hind paw to scratch the injection site once or more until the hind paw touched the ground or the mouse retracted its paw and paused. The number of scratches by mice in different groups was statistically analyzed.

[0089] (4) Experimental Results

[0090] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group mice was significantly increased (P < 0.005), indicating successful model establishment. Compared with the model group, there was no significant difference in the low-dose essential oil group, which had no significant effect on improving serotonin-induced itching in mice. The low-dose and medium-dose essential oil groups showed a significant decrease (P < 0.05), and the high-dose essential oil group also showed a significant decrease in the number of scratches (P < 0.001), indicating that both 1% and 2% concentrations of essential oil ointment had a significant effect on improving serotonin-induced acute itching in mice.

[0091] Table 5. Serum levels in mice treated with essential oil ointment for acute itching and scratching.

[0092] Blank control group 27.5±8.79 Serotonin + Vaseline group <![CDATA[71.88±16.87 ### ]]> Serotonin + low-dose essential oil group <![CDATA[33.75±6.80 ** ]]> Serotonin + essential oil medium dose group <![CDATA[23.63±9.79 ** ]]> Serotonin + high-dose essential oil group <![CDATA[10.00±3.64 *** ]]>

[0093] (Experimental data are expressed as Mean±SEM. * indicates significant difference between each drug administration group and the model group, *p<0.5, **p<0.05, ***p<0.001, # indicates significant difference between the model group and the blank control group, ###p<0.005.)

[0094] 4. Experimental study on the treatment of histamine-induced acute pruritus model mice with Ligusticum chuanxiong essential oil ointment

[0095] Based on a histamine-induced acute pruritus model in mice, this study investigates the pharmacodynamic effects of Ligusticum chuanxiong essential oil ointment on acute pruritus in mice from a behavioral perspective.

[0096] (1) Establishment of a histamine-induced acute pruritus model in mice

[0097] Five-week-old male ICR mice were acclimatized for one week and then randomly divided into five groups: a blank control group, a histamine group, a low-dose histamine + 0.5% essential oil group, a medium-dose histamine + 1% essential oil group, and a high-dose histamine + 2% essential oil group, with eight mice in each group. The hair on the right side of the neck and back of the mice was shaved, with a shaving area of ​​1cm × 2cm.

[0098] (2) Preparation method of essential oil ointment

[0099] White petrolatum was heated in a 55°C water bath and stirred until melted. After adding chuanxiong essential oil, it was stirred evenly until it cooled and solidified into essential oil ointments with concentrations of 0.5%, 1%, and 2%.

[0100] (3) Administration

[0101] Inducing itching, mice were injected intradermally with 50 μL of histamine solution (0.003 mg / mL) at the hair removal site on the nape of their necks. Except for the blank control group and the model group, which were treated with 100 mg of petroleum jelly, the other groups were given 100 mg of the corresponding ointment at the hair removal site. Immediately after application, the mice were placed in an observation box, and their behavior was recorded on video for 30 minutes under undisturbed conditions.

[0102] After the video recording was completed, it was saved for later review to record the mice's scratching behavior. The scratching behavior of the mice was counted. One scratch was defined as the mouse raising its hind paw to scratch the injection site once or more until the hind paw touched the ground or the mouse retracted its paw and paused. The number of scratches by mice in different groups was statistically analyzed.

[0103] (4) Experimental Results

[0104] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group mice was significantly increased (P < 0.005), indicating successful model establishment. Compared with the model group, there was no significant difference in the low-dose essential oil group, which had no significant effect on improving histamine-induced itching in mice. The low-dose essential oil group significantly reduced scratches (P < 0.5), the medium-dose essential oil group significantly reduced scratches (P < 0.5), and the high-dose essential oil group also significantly reduced scratching frequency (P < 0.5), showing that 0.5%, 1%, and 2% concentrations of essential oil ointment all had a significant effect on improving histamine-induced acute itching in mice.

[0105] Table 6. Histamine-induced acute itching and scratching in mice treated with essential oil ointment.

[0106] Blank control group 22.5±8.38 histamine group <![CDATA[61.33±10.57 ### ]]> Histamine + essential oil low-dose group <![CDATA[33.5±5.14 * ]]> Histamine + essential oil medium dose group <![CDATA[35.00±8.08 * ]]> Histamine + High-dose essential oil group <![CDATA[34.00±10.23 * ]]>

[0107] (Experimental data are expressed as Mean±SEM. * indicates a significant difference between each drug administration group and the model group, *p<0.5; # indicates a significant difference between the model group and the blank control group, ###p<0.005.)

[0108] Experimental Study 2: Treatment of Acute Pruritus Model Mice with Chuanxiong Decoction

[0109] Based on the above-mentioned mouse acute pruritus model induced by pruritants, the pharmacodynamic effects of Chuanxiong Lu (prepared in Example 2) on treating mouse acute pruritus models induced by different pruritants were investigated from the perspective of mouse behavior.

[0110] The experimental procedure is as described above, and the results are as follows:

[0111] 1. Experimental results of treating chloroquine-induced acute pruritus model mice with Chuanxiong decoction

[0112] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group was significantly increased (P < 0.5), indicating successful model establishment. Compared with the model group, the number of scratches in the Chuanxiong Lu treatment group was significantly reduced (P < 0.5), indicating that Chuanxiong Lu has a significant ameliorative effect on chloroquine-induced acute itching in mice.

[0113] Table 7. Acute itching and scratching in mice treated with Chuanxiong Decoction and chloroquine.

[0114] Blank group 25.38±9.93 Chloroquine group <![CDATA[93±33.65 # ]]> Chloroquine + Ligusticum striatum group <![CDATA[65.38±21.43 * ]]>

[0115] (Experimental data are expressed as Mean±SEM. * indicates a significant difference between each drug administration group and the model group, *p<0.5; # indicates a significant difference between the model group and the blank control group, #p<0.5.)

[0116] 2. Experimental results of Chuanxiong Decoction in treating LP44-induced acute pruritus model mice

[0117] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group was significantly increased (P < 0.001), indicating successful model establishment. Compared with the model group, the number of scratches in the Chuanxiong Lu treatment group was significantly reduced (P < 0.001), indicating that Chuanxiong Lu has a significant ameliorative effect on LP44-induced acute pruritus in mice.

[0118] Table 8. Acute itching and scratching in LP44 mice treated with Chuanxiong decoction.

[0119] Blank group 25.38±9.93 LP44 group <![CDATA[90±17.51 ### ]]> LP44+Ligusticum striatum group <![CDATA[15.13±4.83 *** ]]>

[0120] (Experimental data are expressed as Mean±SEM. * indicates a significant difference between each drug administration group and the model group, ***p<0.001; # indicates a significant difference between the model group and the blank control group, ###p<0.001.)

[0121] 3. Experimental results of Chuanxiong Decoction in treating serotonin-induced acute pruritus model mice

[0122] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group was significantly increased (P < 0.01), indicating successful model establishment. Compared with the model group, the number of scratches in the Chuanxiong Lu treatment group was significantly reduced (P < 0.5), indicating that Chuanxiong Lu has a significant ameliorative effect on serotonin-induced acute itching in mice.

[0123] Table 9. Serum levels and acute itching / scratching in mice treated with Ligusticum striatum.

[0124] Blank group 25.38±9.93 serotonin group <![CDATA[71.88±16.87 ## ]]> Serotonin + Ligusticum chuanxiong decoction group <![CDATA[24.88±4.03 ** ]]>

[0125] (Experimental data are expressed as Mean±SEM. * indicates a significant difference between each drug administration group and the model group, **p<0.01, # indicates a significant difference between the model group and the blank control group, ##p<0.01.)

[0126] 4. Experimental results of treating histamine-induced acute pruritus model mice with Chuanxiong decoction

[0127] Statistical analysis was performed on the number of scratches in mice from different groups. Compared with the blank control group, the number of scratches in the model group was significantly increased (P < 0.1), indicating successful model establishment. Compared with the model group, the number of scratches in the Chuanxiong Lu treatment group was significantly reduced (P < 0.5), indicating that Chuanxiong Lu has a significant ameliorative effect on histamine-induced acute itching in mice.

[0128] Table 10. Acute histamine-induced itching and scratching in mice treated with Chuanxiong decoction.

[0129] Blank group 25.38±9.93 histamine group <![CDATA[50.63±10.57 # ]]> Histamine + Ligusticum striatum group <![CDATA[35.5±10.32 * ]]>

[0130] (Experimental data are expressed as mean ± SEM. * indicates a significant difference between each drug administration group and the model group, *p<0.5, and # indicates a significant difference between the model group and the blank control group, #p<0.1.)

[0131] Experimental Example 3: Experiment on the treatment of atopic dermatitis with the present invention's Ligusticum chuanxiong essential oil and Ligusticum chuanxiong dew.

[0132] Sixty 5-week-old female BALB / c mice were acclimatized for one week. One day before the experiment, the fur on the backs of the mice was shaved in a 2cm x 3cm area. Fifty mice were randomly selected and their skin was stimulated with 200 μL of 1% 2,4-dinitrochlorobenzene every 3 days for a total of 3 times. Starting on day 12, 100 μL of 0.5% 2,4-dinitrochlorobenzene was used for stimulation every 3 days for a total of 7 times. The induced mice were then randomly divided into a model group, a Ligusticum chuanxiong L group (0.5% Ligusticum chuanxiong essential oil), a Ligusticum chuanxiong M group (1% Ligusticum chuanxiong essential oil), a Ligusticum chuanxiong H group (2% Ligusticum chuanxiong essential oil), and a Ligusticum chuanxiong dew group. A control group of 10 mice (n=10 per group) had their back skin treated with 0.9% sodium chloride solution. The Ligusticum chuanxiong essential oil and Ligusticum chuanxiong dew groups received 200 μL of the corresponding drugs applied to their back skin. The control and model groups received an equal volume of physiological saline. Apply once daily for one week. On the last day of application, record the number of times each mouse scratched its back within 30 minutes.

[0133] Animal models of skin irritation by 2,4-dinitrochlorobenzene (DNCB) are atopic dermatitis (AD) models. This model induces AD-like dermatitis in mice by applying DNCB to their skin, mimicking the symptoms and pathological features of human atopic dermatitis.

[0134] Skin inflammation score:

[0135] After drug administration, the skin damage (redness, scabs, erythema, papules) on the backs of mice was observed, and the degree of skin inflammation was scored as follows: 0 points for no skin damage; 1 point for intact skin barrier with only perceptible inflammatory redness and swelling; 2 points for mild inflammation and mild skin damage with a small amount of erythema and papules; 3 points for inflammatory redness and swelling with a small amount of scabs at the site of skin damage; 4 points for obvious redness and swelling and scabs at the site of skin damage; and 5 points for severe scabs and inflammatory exudation at the site of skin damage.

[0136] Experimental results:

[0137] Table 11 shows that the skin lesions in mice with atopic dermatitis exhibited significant redness, swelling, and crusting, with some mice showing inflammatory exudation on their backs. Application of Ligusticum chuanxiong essential oil or Ligusticum chuanxiong decoction significantly improved the skin lesions, with the high-dose group showing the best effect. Furthermore, the skin lesions in mice with atopic dermatitis were accompanied by severe itching, manifested as constant scratching. Ligusticum chuanxiong essential oil or Ligusticum chuanxiong decoction significantly reduced the frequency of scratching, especially the high-dose group and the Ligusticum chuanxiong decoction group. These results indicate that Ligusticum chuanxiong essential oil and Ligusticum chuanxiong decoction can alleviate skin lesions and itching caused by atopic dermatitis.

[0138] Table 11 Skin condition scores and scratching frequency of mice in each group

[0139] Blank group / 9.0±3.4 Model group 4.6±0.7 <![CDATA[147.0±17.4** ## ]]> Chuanxiong L Group <![CDATA[2.1±0.7 ## ]]> <![CDATA[60.0±12.0** ## ]]> Chuanxiong M Group <![CDATA[1.5±0.5 ## ]]> <![CDATA[46.7±12.9** ## ]]> Chuanxiong H Group <![CDATA[0.8±0.8 ## ]]> <![CDATA[23.1±8.3 ## ]]> Chuanxiong dew group <![CDATA[1.4±0.5 ## ]]> <![CDATA[29.8±9.3 ## ]]>

[0140] Note: Vs blank group, **p<0.01; Vs model group, ##p<0.01.

Claims

1. The use of Ligusticum chuanxiong by-products in the preparation of topical drugs for treating atopic dermatitis; the preparation method of the Ligusticum chuanxiong by-products is to dry fresh Ligusticum chuanxiong according to the drying method of Ligusticum chuanxiong medicinal materials, and obtain the by-products through a condensation device; the drying method of Ligusticum chuanxiong medicinal materials is as follows: take fresh Ligusticum chuanxiong, remove impurities and non-medicinal parts, rinse quickly, place in a cool and ventilated place, air dry, slice, microwave vacuum dry at 50℃ for 2-3 hours, and sieve out the debris to obtain the product.

2. The use according to claim 1, characterized in that: The medication in question is an antipruritic.

3. The use according to claim 1 or 2, characterized in that: The preparations of the aforementioned topical medicines are: gels, ointments, emulsions, sprays, aerosols, lotions, rinses, liniments, coatings, and films.

4. The use according to claim 1, characterized in that: In the aforementioned method for drying Ligusticum chuanxiong, the slices are 2-7 cm in diameter and 2-6 mm thick; the drying time is 2 hours.

Images