Application of portulaca oleracea polysaccharide in preparation of medicine for treating psoriasis

Abstract

The invention firstly discloses application of portulaca oleracea polysaccharide in preparation of the medicine for treating psoriasis, the medicine for treating psoriasis can improve psoriasis-like skin injury and reduce skin tissue inflammation, and the portulaca oleracea polysaccharide is single-component pure polysaccharide extracted from portulaca oleracea and purified. The monosaccharide composition is composed of all or several monosaccharides of rhamnose, arabinose, galactose, glucose, xylose and galacturonic acid, and the molecular weight of the monosaccharide composition is 80-200 kDa. The invention further discloses application of the purslane polysaccharide in preparation of drugs for treating psoriasis and application of the purslane polysaccharide in preparation of cosmetics and medical auxiliary materials for relieving psoriasis-like skin injury. The purslane polysaccharide disclosed by the invention is high in purity, clear in structure and high in safety, has a good psoriasis treatment effect, is superior to dexamethasone in curative effect, can be used as a skin external medicine, a cosmetic, a medical instrument and a medical auxiliary material, and has various potential application values.

Description

Technical Field

[0001] The invention belongs to the field of medical technology, and particularly relates to application of purslane polysaccharide in preparing a drug for treating psoriasis. Background Art

[0002] Psoriasis is a common, chronic, inflammatory, proliferative skin disease that is prone to recurrence. It is an autoimmune dysproliferative skin disease initiated and maintained by T cells under the influence of multiple factors such as polygenic genetic background and environmental stimulation. The typical skin lesions of psoriasis are characterized by red papules or plaques covered with several layers of silvery white scales, accompanied by obvious skin itching. Although psoriasis is not an infectious disease, the skin lesions occur on the skin all over the body, greatly affecting the patient's appearance. Due to the diverse causes and complex etiology, the disease is prone to recurrence, which brings a huge burden to patients.

[0003] At present, the treatment for this type of autoimmune disease mainly includes drug therapy, physical therapy and systemic therapy. Common traditional treatment drugs include methotrexate, cyclosporine, and retinoic acid drugs. Methotrexate has the advantages of significant efficacy, flexible dosage adjustment, and low price, but methotrexate (MTX) may cause liver damage and bone marrow suppression; cyclosporine has the advantage of rapid onset, but may cause nephrotoxicity and hypertension; retinoic acid drugs have the advantages of anti-proliferative effects and wide application, but may cause dry skin and abnormal liver function. Biological agents such as TNF-α inhibitors (etanercept, infliximab, adalimumab, becelizumab), IL-12 / 23 inhibitors (ustekinumab), IL-17A inhibitors (such as secukinumab, ixekizumab, brolimumab), etc., have the advantages of high efficiency, durability, targeting, and safety, but are expensive, restricted for use in special populations, and require high monitoring and management. These drugs cannot cure psoriasis.

[0004] Purslane is an important medicinal plant in the traditional medical system. It has multiple pharmacological effects such as repairing the barrier function of the skin stratum corneum, relieving itching, inhibiting bacteria, and regulating immunity. Purslane is mostly used as medicine with its dried above-ground parts, and some of the whole plants are used as medicine. It is considered to be a traditional Chinese medicine that is effective in treating skin diseases. "Qianjin Fang" records: "For children with umbilical sores that have not been rubbed for a long time, burn purslane and apply it." This shows that in ancient times, purslane was crushed to extract juice or directly applied to treat eczema. A large number of reports have shown that the topical application of compound purslane solution can effectively treat acute eczema. In addition, purslane extracts are used in various skin care products for the auxiliary treatment of acne because of their acne-removing and anti-allergic effects.

[0005] Polysaccharides are one of the main functional components in plants, with antioxidant, anti-inflammatory, and anti-aging activities. Many studies have shown that polysaccharides have the activity of repairing skin damage and skin aging caused by UVB. The antibacterial activity and good mechanical properties of polysaccharides make them potential as wound healing dressings. The high water retention of polysaccharides is also often used as a moisturizer in cosmetics. The biological activity and health benefits of purslane polysaccharides have been extensively studied in vivo and in vitro. Some studies have shown that purslane polysaccharides have anti-fatigue, anti-diabetic, anti-viral, anti-tumor, anti-colitis, and immunomodulatory effects.

[0006] At present, there is no report on whether purslane can treat psoriasis, and its effective ingredients are still unclear. Therefore, purslane polysaccharides may be a potential drug for the treatment of psoriasis. The structure of purslane polysaccharides obtained by traditional methods is not clear, and the corresponding physiological activity is still unclear, especially for autoimmune diseases. Therefore, it is necessary to develop purslane polysaccharides and purify and characterize their components from the perspective that purslane is traditionally used for the treatment of skin diseases, investigate its effect and mechanism of action in the treatment of psoriasis, and realize the application value of purslane polysaccharides. Summary of the invention

[0007] In order to meet the above needs, the present invention provides the use of purslane polysaccharide in the preparation of a drug for treating psoriasis.

[0008] In order to solve the above technical problems, the present invention is implemented through the following technical solutions:

[0009] The invention discloses an application of purslane polysaccharide in preparing a drug for treating psoriasis, wherein the drug for treating psoriasis can improve psoriasis-like skin damage and reduce skin tissue inflammation.

[0010] Furthermore, the purslane polysaccharide is a high-purity purslane polysaccharide extracted from purslane and obtained through purification, and its components are composed of all or several monosaccharides of rhamnose, arabinose, galactose, glucose, xylose, and galacturonic acid, and its molecular weight is 80-200kDa.

[0011] Further, the purslane polysaccharide is composed of five monosaccharides, namely rhamnose, arabinose, galactose, glucose and xylose. The molecular weight of the purslane polysaccharide is 100-150 kDa, and the molar ratio of rhamnose, arabinose, galactose, glucose and galactose in the purslane polysaccharide is 4-7:25-35:26-36:27-37:0.5-5. The polysaccharide chain of the purslane polysaccharide is connected by 4)-β-Glcp-(1→4)-β-Glcp-(1, 5)-α-Araf-(1→4)-α-Galp-(1, →3, ...

[0012]

[0013] Among them, m=750~900, n=32~80, m'=30~60, n'=3~30.

[0014] Furthermore, the purslane polysaccharide is composed of five monosaccharides: rhamnose, arabinose, galactose, xylose and galacturonic acid. The molecular weight of the purslane polysaccharide is 90-130 kDa, and the molar ratio of rhamnose, arabinose, galactose, xylose and galacturonic acid in the purslane polysaccharide is 5-15:15-30:15-30:1-6:35-55. The polysaccharide chain of the purslane polysaccharide is connected by →4)-GalAp-(1→, →4)-α-GalAp-(1→5)-α-Araf-(1→, →2,4)-α-Rhap-(1→). The structural formula of the purslane polysaccharide is:

[0015]

[0016] Among them, m=1600~2500, n=40~120, m'=60~160.

[0017] Furthermore, the drug for treating psoriasis is a drug for external use on the skin.

[0018] Furthermore, the dosage form of the skin external medicine is a gel, a patch, an ointment, an oil or a cream.

[0019] Application of purslane polysaccharide in the preparation of medicines, cosmetics, medical devices or pharmaceutical excipients for alleviating psoriasis-like skin damage.

[0020] The beneficial effects of the present invention are:

[0021] The invention extracts and purifies high-purity purslane polysaccharide from purslane, has a significant effect on the treatment of psoriasis, greatly alleviates psoriasis-like skin damage and reduces skin tissue inflammation, and the effect is better than dexamethasone.

[0022] The present invention obtains high-purity single-component purslane polysaccharide from purslane through an efficient purification method, which has the advantage of high purity; in addition, detailed structural characterization confirms the fine structure of purslane polysaccharide, which is limited to a specific monopolysaccharide type and has uniqueness and exclusivity.

[0023] The present invention finds through animal experiments and immunomodulation experiments that the purslane polysaccharide obtained by the present invention overcomes the shortcomings of traditional psoriasis treatment drugs, such as limited efficacy, large side effects, infection risks and high prices.

[0024] The purslane polysaccharide prepared by the present invention has low cost, easy-to-obtain raw materials, good effect in treating psoriasis, high safety, and can be expected to be used in the preparation of external skin medicines, cosmetics, medical devices or pharmaceutical excipients for treating psoriasis, and has multiple potential application values.

[0025] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. The specific implementation of the present invention is given in detail by the following embodiments and their accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0027] Figure 1 This is the one-dimensional nuclear magnetic resonance spectrum (1H-NMR, 13C-NMR) of the purslane polysaccharide POP-1 in Example 1 of the present invention.

[0028] Figure 2 This is a two-dimensional nuclear magnetic resonance spectrum (COSY spectrum, HSQC spectrum, HMBC spectrum, HSQC-TOSCY spectrum) of the purslane polysaccharide POP-1 in Example 1 of the present invention.

[0029] Figure 3 This is a schematic diagram of the structural formula of the purslane polysaccharide POP-1 in Example 1 of the present invention.

[0030] Figure 4 This is the one-dimensional nuclear magnetic resonance spectrum (1H-NMR, 13C-NMR) of the purslane polysaccharide POP-3 in Example 2 of the present invention.

[0031] Figure 5 This is a two-dimensional nuclear magnetic resonance spectrum (COSY spectrum, HSQC spectrum, HMBC spectrum, HSQC-TOSCY spectrum) of the purslane polysaccharide POP-3 in Example 2 of the present invention.

[0032] Figure 6 This is a schematic diagram of the structural formula of Purslane polysaccharide POP-3 in Example 2 of the present invention.

[0033] Figure 7 This is a diagram showing the effects of Purslane polysaccharides POP-1 and POP-3 on HaCaT cell migration in Example 3 of the present invention.

[0034] Figure 8 This is a graph showing the effects of Purslane polysaccharides POP-1 and POP-3 on HaCaT cell proliferation in Example 3 of the present invention.

[0035] Fig. 9 This is a diagram showing the effects of Purslane polysaccharides POP-1 and POP-3 on HaCaT cell necrosis in Example 3 of the present invention.

[0036] Fig.10 This is a picture of the back skin of mice with psoriasis-like inflammation in Example 4 of the present invention.

[0037] Fig.11 This is a graph showing the changes in skin, body weight and spleen of mice treated with IMQ-induced and POP-treated purslane polysaccharides POP-1 and POP-3 in Example 4 of the present invention.

[0038] Fig.12 This is a graph showing the levels of inflammatory factors in the skin and serum of mice with psoriasis-like inflammation treated with purslane polysaccharides POP-1 and POP-3 in Example 4 of the present invention.

[0039] Fig.13 This is a picture of the back skin condition of mice after applying purslane polysaccharides POP-1 and POP-3 in Example 5 of the present invention.

[0040] Fig.14 This is a graph showing the changes in body weight and organ coefficients of mice after application of purslane polysaccharides POP-1 and POP-3 in Example 5 of the present invention.

[0041] Fig.15 This is a diagram showing the HE staining results of mouse sections after applying purslane polysaccharides POP-1 and POP-3 in Example 5 of the present invention.

[0042] Fig.16 This is a picture of the gel prepared using purslane polysaccharide of the present invention. DETAILED DESCRIPTION

[0043] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. The descriptions herein are used to provide a further understanding of the present invention and constitute a part of this application. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0044] The invention provides the use of purslane polysaccharide in preparing a drug for treating psoriasis. The drug for treating psoriasis can improve psoriasis-like skin damage and reduce skin tissue inflammation.

[0045] The purslane polysaccharide is a single-component pure polysaccharide extracted from purslane and obtained after purification. Its components are composed of all or several monosaccharides of rhamnose, arabinose, galactose, glucose, xylose, and galacturonic acid, and its molecular weight is 80 to 200 kDa. The purslane polysaccharide has the effect of alleviating psoriasis-like skin damage.

[0046] Preferably, the purslane polysaccharide is purslane polysaccharide POP-1, the molecular weight of the purslane polysaccharide POP-1 is 100-150 kDa, the purslane polysaccharide POP-1 is composed of five monosaccharides, namely rhamnose, arabinose, galactose, glucose and xylose, and the molar ratio of rhamnose, arabinose, galactose, glucose and galactose is 4-7:25-35:26-36:27-37:0.5-5.

[0047] The polysaccharide chains of the purslane polysaccharide POP-1 are connected by 4)-β-Glcp-(1→4)-β-Glcp-(1, 5)-α-Araf-(1→4)-α-Galp-(1, →3, 5)-α-Araf-(1→4)-α-Galp-(1, 4)-β-Glcp-(1→4)-β-Glcp-(1, 5)-α-Araf-(1→4)-α-Galp-(1, 4)-β-Glcp-(1→ ...

[0048]

[0049] In the above formula, m=750-900, n=32-80, m'=30-60, n'=3-30.

[0050] Preferably, the purslane polysaccharide may also be purslane polysaccharide POP-3, which is composed of five monosaccharides: rhamnose, arabinose, galactose, xylose and galacturonic acid. The molecular weight of the purslane polysaccharide POP-3 is 90 to 130 kDa, and the molar ratio of rhamnose, arabinose, galactose, xylose and galacturonic acid in the purslane polysaccharide POP-3 is 5 to 15:15 to 30:15 to 30:1 to 6:35 to 55.

[0051] The polysaccharide chains of the purslane polysaccharide POP-3 are connected by →4)-GalAp-(1→, →4)-α-GalAp-(1→5)-α-Araf-(1→, →2,4)-α-Rhap-(1→), and the structural formula of the purslane polysaccharide POP-3 is:

[0052]

[0053] In the above formula, m=1600-2500, n=40-120, m'=60-160.

[0054] Several examples are provided below to further illustrate the preparation methods of the purslane polysaccharides POP-1 and POP-3 of the present invention, and to verify the authenticity of the purslane polysaccharides of the present invention in alleviating psoriasis-like skin damage.

[0055] Example 1 Preparation and structural analysis of purslane polysaccharide POP-1

[0056] 1. Preparation of Purslane Polysaccharide POP-1:

[0057] Step 1) After the purslane is crushed, 75% ethanol is added and refluxed at 80° C. for 2 hours to remove impurities such as small molecular sugars and lipids; the residue is extracted with boiling water at 100° C. for 2 hours, extracted twice and then filtered;

[0058] Step 2) the filtrate is concentrated by using an ultrafiltration membrane with a molecular weight cutoff of 10 kDa, and anhydrous ethanol is added for alcohol precipitation to obtain crude polysaccharide; after redissolving, the polysaccharide is decolorized by using a macroporous resin, and then Sevage reagent (chloroform: n-butanol = 5:1) is added to remove protein, and the upper polysaccharide layer is collected, concentrated under reduced pressure, and dialyzed to obtain crude purslane polysaccharide;

[0059] Step 3) The polysaccharide sample was made into a 50 mg / mL sample solution, purified using a DEAE-cellulose chromatography column, and the 0 M salt eluate was collected, concentrated under reduced pressure, dialyzed with a 3.5 kDa dialysis bag, centrifuged, and freeze-dried to obtain the purslane polysaccharide POP-1.

[0060] 2. Structural analysis of purslane polysaccharide POP-1:

[0061] The prepared purslane polysaccharide POP-1 was subjected to UV analysis, monosaccharide composition analysis, infrared analysis, methylation test and nuclear magnetic resonance analysis.

[0062] (1) UV analysis: Accurately weigh 1 mg of the purslane polysaccharide POP-1 sample and dissolve it to 0.5 mg / mL. Using deionized water as a blank control, use a UV spectrophotometer to perform a full wavelength scan in the wavelength range of 190-700 nm to observe the absorption of the sample. There is no absorption at 280 nm and 260 nm, indicating that the purslane polysaccharide POP-1 basically does not contain protein and nucleic acid impurities.

[0063] (2) Analysis of monosaccharide composition: The purslane polysaccharide POP-1 was degraded with trifluoroacetic acid, and the monosaccharide composition in the degradation product was analyzed using high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD). The retention times of different monosaccharide standards were compared, and different monosaccharides were quantitatively analyzed using the external standard method.

[0064] The results of quantitative analysis of monosaccharides showed that Purslane polysaccharide POP-1 was a neutral sugar component, with arabinose, galactose and glucose as the main monosaccharides, and a small amount of rhamnose and xylose. The molar ratio of rhamnose, arabinose, galactose, glucose and galactose was 5.69:30.23:31.24:31.35:1.49.

[0065] (3) Molecular weight determination: GPC-MALLS-RI was used for analysis. The results showed that the molecular weight of the purslane polysaccharide POP-1 was 122.30 kDa.

[0066] (4) Infrared analysis: The infrared spectrum of the purslane polysaccharide POP-1 sample was measured using an infrared spectrometer and the attenuated total reflectance (ATR) method. The results showed that the purslane polysaccharide POP-1 mainly contained β-glycosidic bonds.

[0067] (5) Methylation test: Weigh the purslane polysaccharide POP-1 sample, participate in the methylation reaction, then acid-base hydrolysis, and perform GC-MS detection. The experimental results show that in purslane polysaccharide POP-1, the connection modes of sugar residues include 1,4-Glcp, 1,4-Galp, T-Galp, 5-Araf and other forms. Several uronic acid residues account for 70.7% of the total sugar residues, among which 1,4-Glcp, 1,4-Galp and T-Galp have the highest content, accounting for 58.7% of the total sugar residues. It can be seen that purslane polysaccharide POP-1 is mainly composed of glucose and galactose connected by 1,4-glycosidic bonds to form the main chain structure.

[0068] (6) Nuclear magnetic resonance analysis: Weigh 50 mg of the purslane polysaccharide POP-1 sample, replace the active hydrogen in the polysaccharide with deuterated water, and perform one-dimensional and two-dimensional nuclear magnetic resonance experiments at 25°C to obtain 1 H spectrum, 13 C spectrum, COSY spectrum, HSQC spectrum, HMBC spectrum, HSQC-TOSCY spectrum.

[0069] See also Figure 1 As shown, Figure 1 This is a one-dimensional nuclear magnetic resonance spectrum of the purslane polysaccharide POP-1 in Example 1 (Figure A corresponds to 1H-NMR, and Figure B corresponds to 13C-NMR). Figure 1 The results showed that the glucose residues of the purslane polysaccharide POP-1 were in β-configuration, the galactose residues were in α-configuration, and the arabinose residues were in α-configuration. Figure 1 middle.

[0070] Two-dimensional nuclear magnetic resonance homonuclear correlation spectra: COSY spectrum, HSQC spectrum, HMBC spectrum, HSQC-TOSCY spectrum, further analyzed the structure of purslane polysaccharide POP-1, see Figure 2 As shown, Figure 2This is a two-dimensional nuclear magnetic resonance spectrum of the purslane polysaccharide POP-1 in Example 1 (Figure A corresponds to the COSY spectrum, Figure B corresponds to the HSQC spectrum, Figure C corresponds to the HMBC spectrum, and Figure D corresponds to the HSQC-TOSCY spectrum). Figure 2 The results showed that the important sugar residues contained in the purslane polysaccharide POP-1 were: 4)-β-Glcp-(1→4)-β-Glcp-(1, 5)-α-Araf-(1→4)-α-Galp-(1, →3,5)-α-Araf-(1→4)-α-Galp-(1, which was consistent with the GC-MS results.

[0071] Finally, it was inferred that the structure sequence of Purslane polysaccharide POP-1 was mainly composed of homopolymeric glucose chains of 4)-β-Glcp-(1→, containing some arabinogalactan of 5)-α-Araf-(1→4)-α-Galp-(1→,3,5)-α-Araf-(1→4)-α-Galp-(1→,3,5)-α-Araf-(1→4)-α-Galp-(1→,3,5)-α-Araf-(1→4)-α-Galp-(1→,3,5)-

[0072] Example 2 Preparation and structural analysis of purslane polysaccharide POP-3

[0073] 1. Preparation of Purslane Polysaccharide POP-3:

[0074] Step 1) After the purslane is crushed, 75% ethanol is added and refluxed at 80° C. for 2 hours to remove impurities such as small molecular sugars and lipids; the residue is extracted with boiling water at 100° C. for 2 hours, extracted twice and then filtered;

[0075] Step 2) the filtrate is concentrated by using an ultrafiltration membrane with a molecular weight cutoff of 10 kDa, and anhydrous ethanol is added for alcohol precipitation to obtain crude polysaccharide; after redissolving, the polysaccharide is decolorized by using a macroporous resin, and then Sevage reagent (chloroform: n-butanol = 5:1) is added to remove protein, and the upper polysaccharide layer is collected, concentrated under reduced pressure, and dialyzed to obtain crude purslane polysaccharide;

[0076] Step 3) The polysaccharide sample was made into a 50 mg / mL sample solution, purified using a DEAE-cellulose chromatography column, and the 0.2 M salt eluate was collected, concentrated under reduced pressure, dialyzed with a 3.5 kDa dialysis bag, centrifuged, and freeze-dried to obtain the purslane polysaccharide POP-3.

[0077] 2. Structural analysis of purslane polysaccharide POP-3:

[0078] The prepared purslane polysaccharide POP-3 was subjected to UV analysis, monosaccharide composition analysis, infrared analysis, methylation test and nuclear magnetic resonance analysis.

[0079] (1) UV analysis: Accurately weigh 1 mg of the purslane polysaccharide POP-3 sample and dissolve it to 0.5 mg / mL. Using deionized water as a blank control, use a UV spectrophotometer to perform a full wavelength scan in the wavelength range of 190-700 nm to observe the absorption of the sample. There is no absorption at 280 nm and 260 nm, indicating that the purslane polysaccharide POP-3 basically does not contain protein and nucleic acid impurities.

[0080] (2) Analysis of monosaccharide composition: The purslane polysaccharide POP-1 was degraded with trifluoroacetic acid, and the monosaccharide composition in the degradation product was analyzed using high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD). The retention times of different monosaccharide standards were compared, and different monosaccharides were quantitatively analyzed using the external standard method.

[0081] The results of monosaccharide quantitative analysis showed that Purslane polysaccharide POP-3 was an acidic sugar component, with galacturonic acid, rhamnose, arabinose and galactose as the main monosaccharides, and a small amount of xylose. The molar ratio of rhamnose, arabinose, galactose, xylose and galacturonic acid was 10.42:22.82:20.60:3.33:42.83.

[0082] (3) Molecular weight determination: GPC-MALLS-RI was used for analysis. The results showed that the molecular weight of the purslane polysaccharide POP-3 was 114.50 kDa.

[0083] (4) Infrared analysis: The infrared spectrum of the purslane polysaccharide POP-3 sample was measured using an infrared spectrometer and the attenuated total reflectance (ATR) method. The results showed that the purslane polysaccharide POP-3 mainly contained α-type glycosidic bond-linked polysaccharides, with some β-type glycosidic bond-linked polysaccharides in the middle.

[0084] (5) Methylation test: Weigh the purslane polysaccharide POP-3 sample, participate in the methylation reaction, then acid-base hydrolysis, and perform GC-MS detection. The experimental results show that in purslane polysaccharide POP-3, the connection modes of sugar residues are 1,4-GalA, T-Galp, 1,3-Galp, 1,6-Galp and other forms, and several uronic acid residues account for 61.2% of the total sugar residues; among them, 1,4-GalA has the highest content, accounting for 47.2% of the total sugar residues. It can be seen that purslane polysaccharide POP-3 is mainly composed of galacturonic acid connected by 1,4-glycosidic bonds to form the main chain structure.

[0085] (6) Nuclear magnetic resonance analysis: Weigh 50 mg of the purslane polysaccharide POP-3 sample, replace the active hydrogen in the polysaccharide with deuterated water, and perform one-dimensional and two-dimensional nuclear magnetic resonance experiments at 25°C to obtain 1 H spectrum, 13 C spectrum, COSY spectrum, HSQC spectrum, HMBC spectrum, HSQC-TOSCY spectrum.

[0086] See also Figure 4 As shown, Figure 4 This is a one-dimensional nuclear magnetic resonance spectrum of the purslane polysaccharide POP-3 in Example 2 (Figure A corresponds to 1H-NMR, and Figure B corresponds to 13C-NMR). Figure 4 The results showed that the galacturonic acid residues of the purslane polysaccharide POP-3 were in α configuration. Figure 4 middle.

[0087] Two-dimensional nuclear magnetic resonance homonuclear correlation spectra: COSY spectrum, HSQC spectrum, HMBC spectrum, HSQC-TOSCY spectrum, further analysis of the structure of purslane polysaccharide POP-3, please refer to Figure 5 , Figure 5 This is a two-dimensional nuclear magnetic resonance spectrum of the purslane polysaccharide POP-3 in Example 2 (wherein Figure A corresponds to the COSY spectrum, Figure B corresponds to the HSQC spectrum, Figure C corresponds to the HMBC spectrum, and Figure D corresponds to the HSQC-TOSCY spectrum). Figure 5 The results showed that the important sugar residues contained in the purslane polysaccharide POP-3 were: →4)-α-GalAp-(1, →5)-α-Araf-(1→, →2,4)-α-Rhap-(1→, which were consistent with the GC-MS results.

[0088] Finally, it was inferred that the main chain of the purslane polysaccharide POP-3 was mainly composed of 1,4-linked galacturonic acid, in which the galacturonic acid was highly methylated to form a homogalacturonic acid (HG) type region. Part of the main chain was composed of →4)-α-GalAp-(1→5)-α-Araf-(1→), which constituted the structural sequence of the arabinogalacturonic acid polysaccharide region. In the arabinogalacturonic acid polysaccharide region, there were side chains linked by →2,4)-α-Rhap-(1→.

[0089] Table 1

[0090]

[0091] See Table 1, which is a comparison table of purslane polysaccharides obtained from different sources and preparation processes. Among them, "Document 1" is Zhao R, Gao X, Cai Y, Shao X, Jia G, Huang Y, Qin X, Wang J, Zheng T, Zhou D, Yang D, Li Y,CaiX,Li D,Liu H, Zhou N.Purification and characterization of an antitumorpolysaccharide from Portulaca oleracea L.Carbohydr Polym.2013Apr2; 93(2):395-400; "Document 4" is Yang Y, Li H, Wang F, Jiang P, Wang G. An arabinogalactan extracted with alkali from Portulaca oleracea L. used as an immunopotentiator and avaccine carrier in its conjugate to BSA.Carbohydr Polym.2023Sep 15;316:120998.

[0092] It can be seen from Table 1 that the two purslane polysaccharides (POP-1 and POP-3) prepared in the present invention have more clear structures, and their active effects can be better studied.

[0093] Example 3 Study on the immunomodulatory activity of purslane polysaccharide in treating psoriasis

[0094] 1. Effect of Purslane Polysaccharide on Migration of HaCaT Cells:

[0095] Cell migration represents the ability of cells to heal. Figure 7 As shown, Figure 7 This is a diagram showing the effect of purslane polysaccharides (POP-1, POP-3) on HaCaT cell migration in Example 3. Figure 7 The results showed that at 6 hours, compared with the control group, the healing area of ​​the drug-added groups (POP-1 and POP-3 groups) increased, and cell migration increased; at 12 hours, the healing area of ​​the control group was still less than that of the drug-added groups (POP-1 and POP-3 groups); at 24 hours, the POP-1 group was basically completely healed, and the POP-3 group was completely healed. Stimulating and effective wound healing agents can effectively avoid the severity and recurrence of psoriasis. This result shows that purslane polysaccharides POP-1 and POP-3 can repair skin damage caused by psoriasis.

[0096] 2. Effect of Purslane Polysaccharide on HaCaT Cell Proliferation:

[0097] HaCaT cells are the most commonly used model for studying the cellular mechanisms of psoriasis. The viability of HaCaT cells was measured using the CCK-8 method. Figure 8 As shown, Figure 8 This is a graph showing the effect of purslane polysaccharides (POP-1, POP-3) on the proliferation of HaCaT cells in Example 3. Figure 8 The results in Figure A show that according to the half-inhibitory concentration, the sample concentration of the experiment was selected as 200 μg / mL for mechanism exploration; secondly, KGF was used to construct a model of excessive proliferation of HaCaT cells. Figure 8 The results in Figure B show that compared with the model group, the cell viability decreased after administration of POP-1 and POP-3, indicating that the purslane polysaccharides POP-1 and POP-3 relieve the symptoms of psoriasis by inhibiting the excessive proliferation of keratinocytes.

[0098] 3. Effect of Purslane Polysaccharide on HaCaT Cell Necrosis:

[0099] Cell necrosis will cause intracellular acid dehydrogenase (LDH) to be released into the culture medium. When cells are in a necrotic or toxic state, the level of ATP will decrease, indicating cell necrosis. The amount of LDH released by HaCaT cells and the amount of ATP released by HaCaT cells were measured. Fig. 9 As shown, Fig. 9 This is a graph showing the effect of purslane polysaccharides (POP-1, POP-3) on HaCaT cell necrosis in Example 3. Fig. 9 The results in Figure A show that after adding purslane polysaccharides (POP-1 and POP-3) to HaCaT cells, the LDH content did not increase compared with the control group; Fig. 9 The results in Figure B show that different concentrations of POP-1 and POP-3 did not significantly reduce the level of intracellular ATP compared with the control group. Combined with the above experimental results, it shows that Purslane polysaccharides POP-1 and POP-3 do not induce cell necrosis.

[0100] Example 4 Study on the activity of purslane polysaccharide in treating psoriasis

[0101] 1. Evaluation of the appearance of the back skin of mice with psoriasis-like inflammation:

[0102] Purslane polysaccharides POP-1 and POP-3 were selected as the active ingredients of purslane polysaccharides for the treatment of psoriasis. In order to avoid the experimental influence caused by matrix factors and the result error, a blank hydrogel group was set up as a negative control group. 5% IMQ was applied to the back of the experimental group mice every day. After 3 days of application, obvious inflammatory reactions (obvious erythema, scaling accompanied by epidermal thickening) appeared on the back skin of the mice. See Fig.10 As shown in the figure, one day after the application of purslane polysaccharide POP-1 and POP-3 hydrogels, obvious erythema and a large number of scales were still visible on the backs of mice in each group; four days after the application, obvious erythema and scales were still visible on the backs of mice in the model group and NC group, but the scales on the backs of mice in the PC group, POP-1 and POP-3 groups were significantly reduced compared with those in the model group, and the psoriasis-like symptoms on the backs of mice in the POP-1 and POP-3 groups were significantly milder than those in the PC group.

[0103] See also Fig.11 As shown, Fig.11The PASI score changes (Figure A), weight changes (Figure B), spleen appearance evaluation (Figure C), and spleen coefficient (Figure D) of the skin of mice induced by IMQ and treated with POP in this embodiment 4. The PASI of the back skin of mice on the last day of the experiment was scored and plotted into a bar graph. The PASI scores of mice in the POP-1 and POP-3 groups were significantly lower than those in the model group, and the POP-1 and POP-3 groups were better than the positive control group, indicating that the purslane polysaccharides POP-1 and POP-3 were better in treating psoriasis; the weight of mice decreased after IMQ induction, and the weight of mice in the POP-1 and POP-3 groups increased compared with the model group, indicating that the purslane polysaccharides POP-1 and POP-3 had a good effect in relieving psoriasis-like inflammation; the spleen was abnormally enlarged after IMQ induction, showing abnormal inflammation. After treatment with the POP-1 and POP-3 groups, the mouse spleen gradually returned to the size of a normal spleen. The positive control drug was dexamethasone, which belongs to a class of topical glucocorticoid drugs. Although it has good anti-inflammatory activity, long-term use of glucocorticoids can cause adverse reactions such as skin atrophy, irritant dermatitis, and weight loss. This shows that Purslane polysaccharide extracted and purified from plants is a good ingredient for the treatment of psoriasis.

[0104] 2. Evaluation of inflammatory factors in the skin and serum of mice with psoriasis-like inflammation:

[0105] Psoriasis is an immune inflammatory skin disease. Inflammatory factors play a vital role in the occurrence and development of psoriasis. Fig.12 As shown, Fig.12 Figure 4 represents the expression levels of inflammatory factors in the skin and serum of mice with psoriasis-like inflammation, wherein Figure A represents the IL-6 level in mouse skin, Figure B represents the TNF-α level in mouse skin, Figure C represents the IL-17A level in mouse skin, Figure D represents the IL-6 level in mouse serum, Figure E represents the TNF-α level in mouse serum, and Figure F represents the IL-17A level in mouse serum.

[0106] Elisa method was used to detect the expression levels of IL-6, TNF-α and IL-17A in serum and skin tissue. Fig.12 The results showed that compared with the blank control group, the levels of IL-6, TNF-α and IL-17A in the serum and skin of the model group were significantly increased; compared with the model group, the levels of IL-6, TNF-α and IL-17A factors in the dexamethasone group and the POP-1 and POP-3 groups were significantly decreased, and the levels of inflammatory factors of POP-1 and POP-3 were the same as those in the dexamethasone group, indicating that the therapeutic effect of Portulaca oleracea polysaccharides POP-1 and POP-3 on psoriasis is comparable to that of dexamethasone.

[0107] Example 5 Safety evaluation study of purslane polysaccharide in treating psoriasis

[0108] Acute toxicity evaluation of POP-1 and POP-3 groups on mice:

[0109] See also Fig.13 and Fig.14 As shown, Fig.13 This is the back skin condition of mice after applying purslane polysaccharides POP-1 and POP-3 in Example 5. Fig.14 The weight changes and organ coefficients of mice after applying purslane polysaccharides POP-1 and POP-3 in Example 5. The skin condition on the back of mice, weight changes and organ coefficients were used as apparent indicators. Fig.13 and Fig.14 The results showed that after applying POP-1 and POP-3, the mice gained weight normally, and no lesions occurred on the back skin. The organ coefficients of the POP-1 and POP-3 groups were the same as those of the control group. Fig.15 As shown, Fig.15 This is the HE-stained section of the mouse in Example 5. Fig.15 The results showed that there was no damage to the heart, liver, spleen, lungs, kidneys and skin of the mice, indicating that purslane polysaccharides POP-1 and POP-3 would not cause toxic interference to mice, ensuring the safety of the use of purslane polysaccharides.

[0110] In summary, the purslane polysaccharide provided by the present invention is derived from common Chinese medicinal materials, which is helpful to develop the potential application value of purslane. At the same time, purslane polysaccharide has a clear structure and has application value in treating psoriasis, which provides a theoretical basis for the value of purslane polysaccharide in skin topical medicines and as cosmetics, medical devices and pharmaceutical excipients.

[0111] Therefore, the purslane polysaccharide of the present invention is expected to be used in the preparation of drugs for treating psoriasis. For example, the purslane polysaccharide of the present invention can be used to prepare a skin topical drug that has the effect of alleviating psoriasis-like skin damage. At the same time, the skin topical drug can also be made into different dosage forms, such as a gel (such as Fig.16 As shown), patches, ointments, oils or creams.

[0112] The purslane polysaccharide of the present invention is also expected to be used in the preparation of medicines, cosmetics, medical devices or pharmaceutical excipients for alleviating psoriasis-like skin damage.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Use of purslane polysaccharide in preparing a drug for treating psoriasis, characterized in that: The drug for treating psoriasis can improve psoriasis-like skin damage and reduce skin tissue inflammation.

2. The use according to claim 1, characterized in that: The purslane polysaccharide is composed of all or several monosaccharides of rhamnose, arabinose, galactose, glucose, xylose and galacturonic acid, and has a molecular weight of 80-200 kDa.

3. The use according to claim 2, characterized in that: The purslane polysaccharide is composed of five monosaccharides: rhamnose, arabinose, galactose, glucose and xylose. The molecular weight of the purslane polysaccharide is 100-150 kDa, and the molar ratio of rhamnose, arabinose, galactose, glucose and galactose in the purslane polysaccharide is 4-7:25-35:26-36:27-37:0.5-5. The polysaccharide chain of the purslane polysaccharide is connected by 4)-β-Glcp-(1→4)-β-Glcp-(1, 5)-α-Araf-(1→4)-α-Galp-(1, →3, ... Among them, m=750~900, n=32~80, m'=30~60, n'=3~30.

4. The use according to claim 2, characterized in that: The purslane polysaccharide is composed of five monosaccharides, namely rhamnose, arabinose, galactose, xylose and galacturonic acid. The molecular weight of the purslane polysaccharide is 90-130 kDa, and the molar ratio of rhamnose, arabinose, galactose, xylose and galacturonic acid in the purslane polysaccharide is 5-15:15-30:15-30:1-6:35-55. The polysaccharide chain of the purslane polysaccharide is connected by →4)-GalAp-(1→, →4)-α-GalAp-(1→5)-α-Araf-(1→, →2,4)-α-Rhap-(1→). The structural formula of the purslane polysaccharide is: Among them, m=1600~2500, n=40~120, m'=60~160.

5. The use according to claim 1, characterized in that: The drug for treating psoriasis is a drug for external use on the skin.

6. The use according to claim 5, characterized in that: The dosage form of the skin external medicine is a gel, a patch, an ointment, an oil or a cream.

7. Application of purslane polysaccharide in the preparation of cosmetics, medical devices or pharmaceutical excipients for alleviating psoriasis-like skin lesions.

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