Medical application of liquiritigenin

Abstract

The invention relates to application of liquiritigenin or pharmaceutically acceptable salt thereof in preparation of a medicine for treating diabetic ulcer. The compound can be used for treating diabetic ulcer.

Description

Technical Field

[0001] The invention relates to the field of medical technology, and in particular to an application of flavonoid compounds. Background Art

[0002] Diabetes mellitus (DM) is a metabolic disorder characterized by chronic hyperglycemia caused by the combined effects of genetic and environmental factors. Its pathogenesis is mainly based on insulin resistance and insufficient insulin secretion. Diabetic ulcers are caused by nerve and vascular damage caused by long-term hyperglycemia. Neuropathy makes patients feel less sensitive and prone to skin damage; while vascular disease causes poor local blood circulation and affects the healing process of wounds. In the early stage of diabetic ulcers, they are only small ulcers or redness and swelling, but as the disease progresses, they gradually develop into deep ulcers accompanied by secretions, infection and necrosis; in severe cases, they may cause foot deformity or amputation risk. At present, the clinical treatment of diabetic ulcers is mainly based on the three traditional theories of neuropathy, vascular occlusion and stenosis, and infection. Treatment measures include anticoagulation, thrombolysis, vasodilation, etc., supplemented by anti-infection treatment and vascular surgery. These treatments are effective for some mild diabetic wounds, but it is difficult to prevent the risk of amputation, and cannot meet the requirements of patients with severe ulcers to restore skin function. Therefore, it is particularly urgent and important to explore and develop treatments that can effectively promote wound healing in diabetic patients. Summary of the invention

[0003] The purpose of the present invention is to provide a new use of licorice root.

[0004] Specifically, the first aspect of the present invention provides the use of glycyrrhizin or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating diabetic ulcers.

[0005] In a preferred embodiment, the above compound or a pharmaceutically acceptable salt thereof is used as the sole active ingredient in the preparation of a medicament for treating diabetic ulcer.

[0006] The details of various aspects of the present invention will be described in detail in the following sections. The features, objectives and advantages of the present invention will become more apparent through the following description and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 Diabetic ulcer model construction flow chart

[0008] Figure 2 Schematic diagram of wound healing in each group of mice

[0009] Figure 3 Wound healing of mice in each group after continuous administration for 3 and 7 days

[0010] Figure 4 Changes of body weight and blood sugar in each group of mice after administration DETAILED DESCRIPTION

[0011] The inventors fed C57BL / 6J mice with a high-fat diet for four weeks, then injected streptozotocin (STZ) intraperitoneally and damaged the back skin, and successfully constructed a diabetic ulcer mouse model (Z. Zhang et al. San Huang Xiao Yan recipe modulates the HMGB1-mediated abnormal inflammatory microenvironment and ameliorates diabetic foot by activating the AMPK / Nrf2 signalling pathway. Phytomedicine. 2023 Sep; 118: 154931.). After the model was constructed, the inventors gave mice different doses of licorice for gavage for one week, and the blood sugar, body weight and wound area of ​​each group of mice were tested on the 0th day, the 3rd day and the 7th day. The results showed that the wound healing rate of diabetic ulcer mice was significantly delayed compared with the normal wound group. After treatment with glycyrrhizin, wound healing of mice with diabetic ulcers was significantly promoted, the skin integrity and inflammatory cell infiltration of mice in the model group were improved, and collagen deposition in the wound increased, showing the positive role of glycyrrhizin in the treatment of diabetic ulcers.

[0012] Furthermore, the present invention provides the use of the following compound of formula (I) or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating diabetic ulcer:

[0013]

[0014] Liquiritigenin, molecular formula: C 15 H 12 O4, molecular weight 256.257.

[0015] The present invention also includes all pharmaceutically acceptable salts corresponding to the above compounds. These salts can be formed by a positively charged part (amino group) in the compound and a negatively charged acid (e.g., hydrochloric acid) with opposite charge; including but not limited to salts generated with the following acids: hydrochloric acid, sulfuric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, phosphoric acid, sulfurous acid, nitric acid, carbonic acid, boric acid, selenious acid, phosphomolybdic acid, phosphorous acid, citric acid, maleic acid, D-malic acid, L-malic acid, DL-malic acid, D-lactic acid, L-lactic acid, DL-lactic acid, oxalic acid, sulfonic acid, benzenesulfonic acid, substituted benzenesulfonic acid, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, phthalic acid, tartaric acid, malonic acid, succinic acid, fumaric acid, citric acid, benzoic acid or substituted benzoic acid.

[0016] The glycyrrhizin of the present invention can be purchased through commercial channels or synthesized using conventional methods in the art, and its purity meets the pharmaceutical standards.

[0017] The glycyrrhizin of the present invention can be used alone or in the form of a pharmaceutical composition. The pharmaceutical composition comprises the glycyrrhizin of the present invention as an active ingredient and a pharmaceutically acceptable carrier. Preferably, the pharmaceutical composition of the present invention contains 0.1 to 99.9% by weight of the glycyrrhizin of the present invention as an active ingredient. The "pharmaceutically acceptable carrier" will not destroy the pharmaceutical activity of the glycyrrhizin of the present invention, and its effective amount, i.e., the amount used when it can play the role of a pharmaceutical carrier, is non-toxic to the human body.

[0018] The pharmaceutically acceptable carriers include, but are not limited to, phospholipids, aluminum stearate, aluminum oxide, ion exchange materials, self-emulsifying drug delivery systems, Tween or other surfactants, serum proteins, buffer substances such as phosphates, aminoacetic acid, sorbic acid, water, salts, electrolytes such as protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, magnesium silicate, partial glyceride mixtures of saturated fatty acids, and the like.

[0019] Other commonly used pharmaceutical excipients include binders (such as microcrystalline cellulose), fillers (such as starch, glucose, anhydrous lactose and lactose beads), disintegrants (such as cross-linked PVP, cross-linked sodium carboxymethyl starch, cross-linked sodium carboxymethyl cellulose, low-substituted hydroxypropyl cellulose), lubricants (such as magnesium stearate), as well as absorption enhancers, adsorption carriers, flavoring agents, sweeteners, excipients, diluents, wetting agents, etc.

[0020] The glycyrrhizin and the pharmaceutical composition thereof of the present invention can be prepared according to conventional methods in the art and can be administered by intestinal, parenteral or topical routes. Oral preparations include capsules, tablets, oral liquids, granules, pills, powders, pills, ointments, etc.; parenteral preparations include injections, etc.; topical preparations include creams, patches, ointments, sprays, etc. Oral preparations are preferred.

[0021] The administration routes of the glycyrrhizin and the pharmaceutical composition thereof of the present invention can be oral, sublingual, intramuscular or subcutaneous, intravenous, urethral, ​​vaginal, etc.

[0022] Compared with the silver ion dressings commonly used in clinical practice, glycyrrhizin can significantly reduce the cost of treatment. As a natural flavoring agent, glycyrrhizin performs better in terms of safety and toxicity. In contrast, silver ion dressings may be toxic to fibroblasts of diabetic patients, reduce cell activity and collagen synthesis, and change cell morphology. Long-term or large-area use of silver ion dressings may also lead to silver deposition disease. In addition, with the widespread use of silver ion dressings, the risk of bacteria developing resistance to silver ions increases, which may weaken its antibacterial effect. Glycyrrhizin has multiple therapeutic effects, including protecting tissues from oxidative damage, promoting cell proliferation and migration, reducing inflammatory responses, and promoting angiogenesis. Its multi-component, multi-target, and multi-pathway synergistic therapeutic effects indicate that glycyrrhizin has broad application prospects in the treatment of diabetic ulcers. In general, glycyrrhizin is not only effective, but also superior to traditional drugs in terms of safety, cost, and drug resistance, providing a better treatment option for patients with diabetic ulcers.

[0023] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually performed under normal conditions or according to the conditions recommended by the manufacturer. Unless otherwise stated, all percentages, ratios, proportions, or parts are by weight.

[0024] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein can be applied to the methods of the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only.

[0025] The above features mentioned in the present invention or the features mentioned in the embodiments can be combined in any way. All the features disclosed in this patent specification can be used in combination with any combination form, and each feature disclosed in the specification can be replaced by any alternative feature that can provide the same, equal or similar purpose. Therefore, unless otherwise specified, the disclosed features are only general examples of equal or similar features.

[0026] Example 1 Licorice root promotes wound healing in diabetic ulcer model mice

[0027] 1. Experimental materials:

[0028] 1.1 Experimental Animals:

[0029] Male C57BL / 6J mice aged 6-8 weeks were purchased from Jiangsu Huachuang Xinnuo Pharmaceutical Technology Co., Ltd. They were kept in a standard Specific Pathogen-Free (SPF) animal room with a temperature of 22-24°C, a humidity of 60%, and a 12-h light cycle. This experimental protocol was approved by the Animal Experiment Ethics Committee of Tongji University, with the ethics approval number: No. TJ-HB-LAC-2024-24. All invasive surgeries were performed under isoflurane inhalation anesthesia, and every effort was made to reduce the suffering of the animals.

[0030] 1.2 Drugs and reagents:

[0031]

[0032] 2. Experimental methods:

[0033] 2.1 Construction of diabetic ulcer model mice:

[0034] Male C57BL / 6J mice aged 6-8 weeks were purchased from Jiangsu Huachuang Xinnuo Pharmaceutical Technology Co., Ltd. The mice were kept in a standard specific pathogen-free (SPF) animal room with an environmental condition of 22-24°C, 60% humidity, and a 12-hour light cycle. This experimental protocol has been approved by the Animal Experiment Ethics Committee of Tongji University, and the ethics approval number is: No. TJ-HB-LAC-2024-24. All invasive surgeries were performed under isoflurane inhalation anesthesia to minimize the pain of the animals. In the process of establishing the diabetic model, after adaptive feeding, the mice were first fed a high-fat diet for four weeks, and then intraperitoneally injected with streptozotocin (STZ), diluted with 1% citric acid buffer (pH 4.2-4.5, prepared in an ice bath, and prepared immediately before use). The control group mice were intraperitoneally injected with an equal amount of citric acid buffer. On the eve of STZ injection, the mice were fasted for 12 hours but not water. The STZ dose (100 mg / kg) was calculated according to the weight of the mice, and the diabetes model was induced by a single intraperitoneal injection. The injection was repeated one day later, and the random blood glucose was detected by collecting the tail vein blood of the mice three days later. The blood glucose level ≥16.7 mmol / L was used as the criterion for the success of the hyperglycemia model. For mice that did not meet the model standard, each mouse was supplemented with 100 mg / kg STZ, and the blood glucose was monitored again three days later. If it still did not meet the standard, it was eliminated. The mice in the normal control group were fed with ordinary feed (fat content 12%, carbohydrate content 60%, protein content 28%), while the mice in the diabetic model group were fed with a high-fat diet (74.5% basic feed, 10% cooked lard, 10% sucrose, 5% egg yolk powder, 0.5% cholesterol). After the successful construction of the diabetes model, the construction of the wound ulcer model was continued. One day before the model was constructed, the mice were anesthetized and all the hair on the back was shaved with a razor, and then thoroughly cleaned with a depilatory cream to expose the back skin. The next day, the mice were anesthetized again, and a 0.6 cm × 0.6 cm round stamp was used to stamp the back of the mice, and an incision was made at the stamp position to construct a diabetic ulcer mouse model. For details, see Figure 1 .

[0035] 2.2 Preparation of Licorice Solution:

[0036] The preparation method of glycyrrhizin solution is as follows: Taking the preparation of 1mL working solution as an example, first take 100μL of clear DMSO stock solution with a concentration of 24.2mg / mL, add it to 400μL of PEG300, and mix it thoroughly to ensure uniformity; then add 50μL of Tween-80 to the mixed system, and mix it again thoroughly; finally, add 450μL of normal saline to the above solution to make the total volume 1mL. In this way, we get a glycyrrhizin solution prepared according to the ratio of 10% DMSO, 40% PEG300, 5% Tween-80 and 45% normal saline.

[0037] 2.3 Animal experiment grouping and sampling:

[0038] In this study, we randomly divided mice into six groups: normal wound (NW), model group (Model), low-dose licorice group (8 mg / kg), medium-dose licorice group (20 mg / kg), high-dose licorice group (50 mg / kg), and positive drug silver ion dressing group (Acasin), see Table 1. Both the normal control group and the model group received equal amounts of normal saline gavage once a day, at about 9:00 in the morning, and samples were collected for testing after 3 and 7 days of continuous administration. During the experiment, we recorded the weight and blood sugar of the mice in detail on the 0th day, 3rd day, and 7th day after the wound ulcer modeling, and took photos to record the wound healing of each group of mice.

[0039] Table 1. Mouse grouping

[0040]

[0041] 2.4 Statistical methods:

[0042] GraphPad Prism 9.0 and SPSS 21.0 software were used to perform statistical analysis on all the above data, and the data were expressed as mean ± SEM. Independent Samples t-test was used for comparison between two groups; one-way ANOVA was used for comparison between multiple groups when the variance was homogeneous; non-parametric tests were used when the normal distribution was not met or the variance was unequal.

[0043] 3. Experimental results:

[0044] Changes in body weight, blood sugar, and wound healing of mice in each group:

[0045] The diabetic ulcer mouse model was established by high-fat diet and streptozotocin induction. Figure 1. Three days after modeling, compared with the wounds of normal mice in the control group (NW), the wound healing of the model group (Model) mice under diabetic conditions was significantly delayed (P < 0.05). After intragastric administration of 20mg / kg and 50mg / kg glycyrrhizin, the wound healing rate was significantly increased (P < 0.05, P < 0.01). Seven days after modeling, compared with the wounds of normal mice in the control group (NW), the wound healing rate of the model group (Model) mice under diabetic conditions was significantly delayed (P < 0.01). After intragastric administration of 20mg / kg and 50mg / kg glycyrrhizin, the wound healing rate was significantly increased (P < 0.05, P < 0.01). High-dose glycyrrhizin can promote wound healing in diabetic ulcer mice and achieve similar efficacy to positive drugs, see Figure 2 and Figure 3 The body weight and blood sugar of mice in each group were not affected. Figure 4 , proving that the wound healing of diabetic ulcer mice treated with licorice root has nothing to do with its blood sugar lowering effect.

[0046] The various aspects of the present invention have been described above. However, it should be understood that, without departing from the spirit of the present invention, equivalent changes and modifications may be made by those skilled in the art, and the changes and modifications also fall within the scope of the claims of the present application.

Claims

1. Use of glycyrrhizin or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating diabetic ulcers.

2. The use of glycyrrhizin or a pharmaceutically acceptable salt thereof according to claim 1, characterized in that: The licorice root or its pharmaceutically acceptable salt is used as the only active ingredient for preparing medicine for treating diabetic ulcer.

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