CN117018020A - Application of swimming bladder glycosaminoglycan in preparation of intestinal injury drugs - Google Patents

Abstract

The invention belongs to the technical field of biological medicines, and relates to application of swimming bladder glycosaminoglycans in preparation of intestinal injury medicines. The swim bladder glycosaminoglycan has obvious intervention effect on intestinal injury of mice, and can improve pathological injuries such as shortened colon length, colonic crypt disorder, inflammatory infiltration and the like. Test data show that the swimming bladder glycosaminoglycan can reduce the content of organism inflammatory factors IL-2 and endotoxin, relieve the increase of organism inflammatory level and intestinal permeability, obviously increase SOD activity and GSH content in colon tissues, obviously reduce MPO activity and MDA content and relieve the occurrence of intestinal oxidative stress and inflammation. The swimming bladder glycosaminoglycan has good application prospect in preparing medicines for treating intestinal injuries.

Description

Application of swim bladder glycosaminoglycans in the preparation of intestinal injury drugs

Technical field

The invention belongs to the technical field of biomedicine and relates to the application of fish swim bladder glycosaminoglycans in preparing intestinal damage drugs.

Background technique

Arsenic contamination in food mainly comes from arsenic-containing pesticides, environmental arsenic pollution, arsenic-containing raw materials, etc., and exists in food in different forms. Arsenic can enter the body through drinking water and food through the digestive tract. Long-term intake can lead to arsenic-induced diseases. Various body toxicities including intestinal damage. Arsenic often exists in the form of compounds, including inorganic arsenic and organic arsenic. Different forms of arsenic have different toxic effects on the human body. Because of the variety of forms, there are still many things worth exploring about the specific toxicity mechanisms of arsenic. As an important digestive and metabolic organ of the human body, the gastrointestinal tract not only digests and absorbs nutrients, but also serves as an important transfer point in the excretion of heavy metals. In recent years, arsenic-induced intestinal toxic effects have gradually attracted attention, so we have discovered preventable Natural active substances that cause intestinal damage due to arsenic and elucidating their specific detoxification mechanisms are of great significance and value in preventing chronic damage caused by heavy metals.

The swim bladder is an important organ for fish to regulate the ups and downs of the body. It is a low-fat and high-protein raw material that has various functions such as promoting blood circulation and removing blood stasis, and beautifying the skin. Swim bladder polysaccharide is one of the active ingredients in fish bladder. It is a macromolecular glycosaminoglycan with →4GlcUAβ1→3GalNAc(4S)β1→ as the main chain. It is a chondroitin sulfate A analogue and has wide application potential.

In the prior art, CN103788222B discloses that Fuc3S4S-substituted oligoglycosaminoglycans and pharmaceutical compositions thereof can be used to prepare antithrombotic drugs. CN110776578B discloses a low-molecular sea cucumber glycosaminoglycan, which has the effects of anti-inflammation, anti-vascular disease, anti-tumor or anti-tumor metastasis, and improvement of learning and memory abilities. In tracing the origin of fish swim bladder efficacy and its modern research progress, the bioactive peptides released from fish swim bladder enzymatic protein show a variety of biological activities, including anti-hypertension, antioxidant, enhanced immune activity, promotion of cell growth and development, immunity, and reduction of inflammatory reactions. , affecting intestinal immunoglobulin (IgA) levels. Two types of glycosaminoglycans have been identified in fish swim bladders, namely chondroitin sulfate and heparan sulfate with molecular weights of 18-40KD, which can mediate tissue repair, regeneration, and wound healing.

Existing technology has found that glycosaminoglycans exhibit strong activity in anti-cancer, anti-tumor, anti-thrombosis, antioxidant and other aspects, showing good application and development prospects. However, there is currently no application of glycosaminoglycans in the intestines. Therefore, the development of the application of fish swim bladder glycosaminoglycans in the preparation of intestinal injury drugs has great development significance and market demand.

Contents of the invention

The object of the present invention is to provide a use of fish swim bladder glycosaminoglycan in protecting intestinal damage. The present invention uses fish bladder as raw material, adds alkaline protease for enzymatic hydrolysis, anion exchange chromatography column purification, absolute ethanol for alcohol precipitation, concentration and freeze-drying to obtain the swim bladder glycosaminoglycan, and further protects the swim bladder glycosaminoglycan. In the mouse intestinal injury test, it was verified that fish swim bladder glycosaminoglycans have a significant intervention effect in protecting intestinal injury, providing technical support for research on effective treatment and prevention of intestinal injury.

Based on the above purpose, the present invention solves this need in the field by providing the application of fish swim bladder glycosaminoglycans in the preparation of intestinal injury drugs.

In one aspect, the present invention relates to the use of glycosaminoglycans in the preparation of injury treatment drugs. The glycosaminoglycans are fish swim bladder glycosaminoglycans. The preparation method of the fish swim bladder glycosaminoglycans: enzymatically hydrolyzes the swim bladder with alkaline protease. , centrifuge the supernatant, purify and elute with an anion exchange chromatography column, and use sodium chloride solutions of different concentrations as the eluent to obtain the swim bladder glycosaminoglycans;

The swim bladder glycosaminoglycans are used to reduce inflammation levels in the body's blood, reduce intestinal permeability, improve colon length shortening, improve colon crypt structural disorder, improve inflammatory infiltration, and alleviate intestinal oxidative stress damage.

Further, the present invention provides an application of glycosaminoglycans in the preparation of drugs for treating intestinal damage. The concentration of the fish swim bladder glycosaminoglycans used to protect intestinal damage is 50 mg/kg-200 mg/kg.

Further, the glycosaminoglycan provided by the present invention is used in the preparation of drugs for treating intestinal damage. The alkaline protease enzymatic hydrolysis conditions are: dry and crush the fish bladder, add a sodium chloride solution containing alkaline protease, and suspend the swim bladder. The solid-liquid ratio in the liquid is 1:10, the amount of sodium chloride added is 6 mg/mL, and the amount of alkaline protease added is 5.4 mg/mL. Stir the enzymatic hydrolysis in a water bath at 55°C for 20 hours, and then inactivate the enzyme, 4000 rpm/min, 5 min. Centrifuge and take the supernatant to obtain the fish bladder enzymatic hydrolyzate.

Further, the application of the glycosaminoglycans provided by the present invention in the preparation of intestinal injury treatment drugs, the elution conditions of the fish swim bladder glycosaminoglycans are: 0.3mol/L, 0.9mol/L and 1.1mol/L Elute with sodium chloride solutions of different concentrations, and use an Amberlite™ FPA98Cl anion exchange chromatography column as a filler for adsorption and purification. The swim bladder glycosaminoglycans are the components obtained by elution with 1.1 mol/L sodium chloride solution.

On the other hand, the present invention relates to a medicine for treating intestinal damage, the components of which include swim bladder glycosaminoglycans and medically acceptable excipients.

As used herein, the term "pharmaceutically acceptable" means no long-term harmful effects on the general health of the subject being treated.

In the present invention, the term "pharmaceutically acceptable excipients" refers to excipients that retain the biological efficacy of swim bladder glycosaminoglycans and have no adverse effects in biology or other aspects. Pharmaceutically acceptable excipients include excipients , one or more of binders, disintegrants, lubricants, coating agents, solvents, cosolvents, suspending agents, thickeners and surfactants. For example, excipients, such as water, physiological saline, etc.; binders, such as cellulose derivatives, alginates, gelatin and/or polyvinylpyrrolidone; wetting agents, such as glycerin; disintegrating agents, such as agar, calcium carbonate and / or sodium bicarbonate; surfactants, such as cetyl alcohol; lubricants, such as talc, calcium/magnesium stearate, polyethylene glycol, etc.

In addition, the pharmaceutical composition of the present invention may further contain other auxiliary materials, such as flavors, sweeteners, etc. According to the known technology in this field, the pharmaceutical composition can be made into various dosage forms according to the needs of the therapeutic purpose and administration route. Preferably, the composition is in a unit dosage form, such as lyophilized agent, tablet, capsule, powder, Emulsion, water injection or spray, more preferably, the pharmaceutical composition is in the form of injection (such as freeze-dried powder injection) or oral dosage form, such as tablets and capsules. Medications may be administered by the conventional routes, in particular enterally, for example orally, in the form of tablets or capsules, or parenterally, for example in the form of injectable solutions or suspensions, topically, for example in lotions or gels. Glue form.

Compared with the prior art, the present invention has the following beneficial effects or advantages:

The swim bladder glycosaminoglycan of the present invention can effectively improve intestinal inflammation and oxidative damage in mice. The present invention found that fish swim bladder glycosaminoglycans can improve the body's inflammatory factors IL-2 and endotoxin levels, alleviate inflammation levels and increase intestinal permeability, and improve jejunal and colon crypt disorders, inflammatory infiltration, etc. Microscopic pathological damage; at the same time, T-SOD activity and GSH content in colon tissue increased significantly, and MPO activity and MDA content decreased significantly, thereby slowing down the occurrence of oxidative stress and inflammation in the intestine. The intervention effect of fish swim bladder glycosaminoglycan on MPO, T-SOD activity and GSH content changes shows a dose effect, that is, as the dose increases, its MPO enzyme activity increases, T-SOD enzyme activity decreases, and GSH content decreases. The intervention effect is more obvious. This intervention is related to the antioxidant, anti-inflammatory and potential prebiotic properties of glycosaminoglycans.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only are some embodiments of the invention.

Figure 1 is a statistical analysis chart for detecting changes in the content of the inflammatory factor IL-2 in mice caused by fish swim bladder glycosaminoglycans. C represents the IL-2 content in the control group; M represents the IL-2 content in the mouse model group; GL represents the IL-2 content in the low-dose test group. The gavage dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the medium dose. The IL-2 content in the test group, the intragastric dose of fish swim bladder glycosaminoglycan is 100mg/kg; GH represents the IL-2 content of the high-dose test group, the intragastric dose is 200mg/kg.

Figure 2 is a statistical analysis chart for detecting changes in endotoxin ET content in mice caused by fish swim bladder glycosaminoglycans. C represents the endotoxin ET content in the control group; M represents the endotoxin ET content in the mouse model group; GL represents the endotoxin ET content in the low-dose test group, and the gavage dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the medium-dose test. The endotoxin ET content in the group, the gavage dose of fish swim bladder glycosaminoglycan is 100mg/kg; GH represents the endotoxin ET content in the high-dose test group, the gavage dose is 200mg/kg.

Figure 3 is a photograph of changes in the colon of mice in each treatment group. C represents the measurement of the appearance structure of the colon in the control group; M represents the measurement of the appearance structure of the mouse model group; GL represents the measurement of the appearance structure of the low-dose test group. The gavage dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the medium dose. The appearance and structure measurement diagram of the test group, the intragastric dose of fish swim bladder glycosaminoglycan is 100mg/kg; GH represents the appearance structure measurement diagram of the high-dose test group, the intragastric dosage is 200mg/kg.

Figure 4 is a statistical analysis chart of the changes in mouse colon length detected by fish bladder glycosaminoglycans. C represents the colon length of the control group; M represents the colon length of the mouse model group; GL represents the colon length of the low-dose test group, the intragastric dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the colon length of the medium-dose test group, swim bladder glycosaminoglycan The intragastric dose of aminoglycan is 100 mg/kg; GH represents the colon length of the high-dose test group, and the intragastric dose is 200 mg/kg.

Figure 5 is a H&E staining picture of the microscopic pathological tissue of the colon of mice in each treatment group. Circles represent crypt structures, hexagons represent goblet cells, and arrows indicate inflammatory infiltration. C represents the pathological tissue of the control group; M represents the pathological tissue of the mouse model group; GL represents the pathological tissue of the low-dose test group, the intragastric dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the pathological tissue of the medium-dose test group, fish bladder glycosaminoglycan The intragastric dose of aminoglycan is 100 mg/kg; GH represents the pathological tissue of the high-dose test group, and the intragastric dose is 200 mg/kg.

Figure 6 is a statistical analysis chart for detecting changes in myeloperoxidase MPO activity in mouse colon tissue caused by fish swim bladder glycosaminoglycans. C represents the MPO activity of the control group; M represents the MPO activity of the mouse model group; GL represents the MPO activity of the low-dose test group, the intragastric dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the MPO activity of the medium-dose test group, fish bladder sugar The intragastric dose of aminoglycan is 100 mg/kg; GH represents the MPO activity of the high-dose test group, and the intragastric dose is 200 mg/kg.

Figure 7 is a statistical analysis chart for detecting changes in MDA content of mouse colon tissue caused by fish swim bladder glycosaminoglycans. C represents the MDA content in the control group; M represents the MDA content in the mouse model group; GL represents the MDA content in the low-dose test group, and the gavage dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the MDA content in the medium-dose test group, and fish bladder sugar The intragastric dose of aminoglycan is 100 mg/kg; GH represents the MDA content of the high-dose test group, and the intragastric dose is 200 mg/kg.

Figure 8 is a statistical analysis chart for detecting changes in T-SOD activity in mouse colon tissue caused by fish swim bladder glycosaminoglycans. C represents the T-SOD activity in the control group; M represents the T-SOD activity in the mouse model group; GL represents the T-SOD activity in the low-dose test group, and the gavage dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the medium-dose test. Group T-SOD activity, the intragastric dose of fish swim bladder glycosaminoglycan is 100mg/kg; GH represents the T-SOD activity of the high-dose test group, the intragastric dose is 200mg/kg.

Figure 9 is a statistical analysis chart of the changes in GSH content in mouse colon tissue detected by fish swim bladder glycosaminoglycans. C represents the GSH content in the control group; M represents the GSH content in the mouse model group; GL represents the GSH content in the low-dose test group, and the gavage dose of swim bladder glycosaminoglycan is 50 mg/kg; GM represents the GSH content in the medium-dose test group, and the swim bladder glycosaminoglycan dose is 50 mg/kg. The intragastric dose of aminoglycan is 100 mg/kg; GH represents the GSH content of the high-dose test group, and the intragastric dose is 200 mg/kg.

Detailed ways

The technical solutions of the present invention will be described below with reference to examples. However, the present invention is not limited to the following examples. The experimental methods and detection methods described in each example are conventional methods unless otherwise specified. The equipment and raw materials mentioned above can be purchased in the market unless otherwise specified.

This example provides an animal test on the protective effect of fish swim bladder glycosaminoglycans on intestinal damage in mice.

Preparation of sodium arsenite solution: Weigh 70 mg of sodium arsenite powder and add 10 mL of physiological saline to prepare a 10 mg/mL sodium arsenite solution. When used, prepare it as a 5mg/mL working solution.

Preparation of the swim bladder glycosaminoglycan solution: Weigh 280 mg of the swim bladder glycosaminoglycan sample and dissolve it in 14 mL of physiological saline to prepare a 20 mg/mL fish swim bladder glycosaminoglycan solution, and then dilute it into 10 mg/mL and 5 mg/mL solutions respectively.

After the fish bladder is dried and crushed, a sodium chloride solution containing alkaline protease is added. The amount of sodium chloride added is 6 mg/mL, and the amount of alkaline protease added is 5.4 mg/mL. The solid-liquid ratio in the fish bladder suspension is 1:10. Stir the enzymatic hydrolysis in a water bath at 55°C for 20 hours, then inactivate the enzyme, centrifuge at 4000 rpm/min for 5 minutes to take the supernatant, and use sodium chloride solutions of different concentrations 0.3 mol/L, 0.9 mol/L, and 1.1 mol/L to elute. Use the filler: Amberlite™ FPA98Cl anion exchange chromatography column adsorption purification, fish swim bladder glycosaminoglycans are the components eluted with 1.1mol/L sodium chloride solution, collect the eluate and add absolute ethanol for alcohol precipitation, take the precipitate and redissolve it with distilled water After dialysis, the fish bladder glycosaminoglycan is obtained by rotary evaporation after dialysis, concentration, and freeze-drying.

Eight-week-old C57BL/6J mice with SPF level were randomly divided into 5 groups by weight (control group, model group, test group GL group, test group GM group, test group GH group), with 12 mice in each group. The test group was divided into three groups according to the intragastric dosage of fish swim bladder glycosaminoglycans. The GL group had an intragastric dosage of 50 mg/kg, the GM group had an intragastric dosage of 100 mg/kg, and the GH group had an intragastric dosage of 200 mg/kg. The fish swim bladder glycosaminoglycan test group was administered gavage doses of fish swim bladder glycosaminoglycan solution in the morning and 5 mg/kg sodium arsenite solution in the afternoon. The model group was administered 0.1 mL/10 g normal saline in the morning and 5 mg/kg sodium arsenite solution in the afternoon. The control group was given 0.1mL/10g normal saline by intragastric administration. After the daily gavage, the mice in each group were allowed to eat freely, and the experimental groups (control group, model group, test group GL group, test group GM group, test group GH group) were given continuous gavage for 38 days. After the last intragastric administration, the mice were sacrificed, and eye serum and colon tissue were collected.

Measurement indicators and methods

(1) Determination of the levels of inflammatory factor IL-2 and endotoxin ET in mouse serum

After the experimental period, blood was obtained by collecting blood from the eyeballs, and centrifuged at 3000 rpm for 20 minutes to obtain serum for later use. The contents of the inflammatory factor IL-2 and endotoxin ET in the serum were measured according to the instructions of the enzyme-linked immunoassay kit (provided by Jiangsu Enzyme Immunobiotics).

(2) Measurement of mouse intestinal length

Use a ruler to measure the length of the colon of mice in each group to measure the pathological changes in colon tissue.

(3) Mouse intestinal tissue staining test

Colon tissue was fixed with 4% paraformaldehyde, dehydrated, waxed, embedded, and sectioned before use at room temperature. The above sections were treated with xylene and alcohol at different concentrations, dewaxed, washed, and stained with hematoxylin and eosin. , dehydrated, sealed, and observed under a 40× microscope.

(4) Determination of myeloperoxidase MPO content in mouse intestinal tissue

Take the colon tissue and cut it into pieces on ice, prepare 10% slurry with physiological saline, centrifuge at 3000 rpm for 15 minutes to collect the supernatant, and measure myeloperoxidase in the tissue according to the instructions of the biochemical kit (provided by Nanjing Jiancheng Institute of Biology) MPO content.

(5) Determination of T-SOD, MDA and GSH content in mouse intestinal tissue

Take the colon tissue and cut it into pieces on ice, prepare 10% slurry with physiological saline, centrifuge at 3000 rpm for 15 minutes to collect the supernatant, and measure the superoxide dismutase (superoxide dismutase) in the tissue according to the instructions of the biochemical kit (provided by Nanjing Jiancheng Institute of Biology). T-SOD), malondialdehyde (MDA) and glutathione (GSH), and the protein concentration was measured according to the instructions of the BCA kit (provided by Beyotime Biotech) for quantitative conversion.

test results

Measurement results of the inflammatory factor IL-2 and endotoxin ET in the serum of mouse eyeballs.

The results in Figure 1 show that compared with control group C, model group M significantly increased the inflammatory factor IL-2 in mice (p<0.05). Under the intervention of swim bladder glycosaminoglycans, the test groups GL, GM and GH group significantly reduced the increase in inflammatory factor IL-2. Compared with the model group, the experimental group GL, GM and GH groups showed a significant downward trend in IL-2 content levels (p<0.05), and were all lower than the model group, and In the medium-dose group, the intragastric dose of 100 mg/kg was the best for intervening IL-2 in the serum of mice under the action of fish swim bladder glycosaminoglycans. Compared with the control group, the results of the test groups GL, GM and GH showed that the IL-2 content of the GL group and GH group was basically no different from the control group, and could be restored to the IL-2 level in normal mouse serum. For Reducing the increase in the inflammatory factor IL-2 in mice had the best protective effect. The above results show that within the gavage dose range set by the present invention, the fish swim bladder glycosaminoglycans at gavage doses of 50 mg/kg and 200 mg/kg have the best effect on protecting the inflammatory factor IL-2 in mice, and are better than those in the medium. Technical effect of 100mg/kg dose group.

The results in Figure 2 show that compared with control group C, model group M increased the endotoxin ET in the intestinal permeability of mice. Under the intervention of swim bladder glycosaminoglycans, the test groups GL and GM significantly reduced endotoxin ET. Endotoxin ET, which represents intestinal permeability, increased (p<0.05). Compared with the model group, the test group GL, GM and GH groups showed a downward trend in endotoxin ET content levels, and were all lower than the model group. group, and the intervention effect of endotoxin ET in the serum of mice under the action of fish swim bladder glycosaminoglycans was best in the medium dose group at a gavage dose of 100 mg/kg. Compared with the control group, the results of the experimental groups GL, GM and GH showed that the ET content in the GH group was basically no different from the control group and could be restored to the level of intestinal permeability endotoxin ET in the serum of normal mice. GL , the GM group significantly reduced the content of ET, and the GM group had the best protective effect on the increase in endotoxin ET, which reduces intestinal permeability in mice. The above results show that within the gavage dose range set by the present invention, the gavage dose of 100 mg/kg of fish bladder glycosaminoglycan has the best effect on protecting the intestinal permeability of mice from endotoxin ET, and is better than the low-dose group. Technical effects of 50mg/kg and high dose group 200mg/kg.

The above results show that the mechanism of action of fish swim bladder glycosaminoglycans is that it can significantly reduce the increase in the inflammatory factor IL-2 and the increase in endotoxin ET levels, and plays an intervention role by reducing the inflammation level in the body's blood and reducing intestinal permeability, and Within the ratio range of this test, the mid-dose 100 mg/kg gavage dose has the best effect on protecting the inflammatory factor IL-2 and intestinal permeability endotoxin ET in mice under the action of fish bladder glycosaminoglycans. And it can restore the mice to normal levels, and is better than the technical effect of the low-dose group of 50 mg/kg and the high-dose group of 200 mg/kg, and can exert a significant intervention effect.

The results of the improvement effect of swim bladder glycosaminoglycans on intestinal histopathological changes in mice.

The pictures taken of the colon length are shown in Figure 3, and the specific measurement results are presented in Figure 4. The results in Figure 3 show that compared with the control group, model group M significantly shortened the colon length (p<0.05). Under the intervention of fish swim bladder glycosaminoglycans, the experimental groups GL, GM and GH could shorten the length of the colon and basically restore it to normal length, and there was basically no difference from the control group. It shows that swim bladder glycosaminoglycan can improve the shortening of the colon length and basically restore it to the normal length of the colon, and within the intragastric dose range set by the present invention, the best effect is achieved at a medium dose of 100 mg/kg.

The magnification of the pictures taken in this example is 40×. Figure 5 shows the microscopic intestinal pathological changes of the colon tissue. Compared with the control group C, the model group M caused the loss of crypts in the colon tissue, the reduction of goblet cells, and the appearance of A large number of inflammatory infiltrates. Compared with model group M, under the intervention of swim bladder glycosaminoglycans, the colon crypt structure was restored, goblet cells increased, and inflammatory infiltration was almost invisible. Compared with the control group, there were basically no differences in colon crypt depth, arrangement, and number of goblet cells in the GL, GM, and GH groups, and no obvious inflammatory infiltration was observed. Within the gavage dose range set by the present invention, the middle dose of 100 mg/kg gavage has the largest crypt depth, the largest number of goblet cells, and the best effect. The above results show that fish bladder polysaccharide has a significant improvement effect on the microscopic pathological damage of intestinal tissue.

Effects of swim bladder glycosaminoglycans on myeloperoxidase MPO, T-SOD, MDA and GSH in mouse intestinal tissue.

The results in Figure 6 show that compared with the control group, the myeloperoxidase activity in the colon tissue of mice in the model group increased by 29.87%, indicating the occurrence of inflammation in the colon. Under the intervention of swim bladder glycosaminoglycans, the myeloperoxidase activities of the test group GL, GM and GH were reduced by 29.20%, 30.88% and 38.18% respectively compared with the model group, showing a dose-dependent decrease. It can be seen that the swim bladder Glycosaminoglycans can significantly alleviate colon inflammation by reducing myeloperoxidase MPO activity.

The test results in Figures 7, 8 and 9 show that compared with control group C, malondialdehyde (MDA), an indicator that indirectly reflects oxidative damage, in the colon tissue of model group M mice increased significantly (p<0.05), while the antioxidant T-SOD and GSH in the acting antioxidant enzyme system were significantly decreased (p<0.05), indicating the occurrence of oxidative stress damage in the mouse intestine. Under the action of swim bladder glycosaminoglycans, the experimental groups GL, GM and GH can effectively protect the intestines of mice, reduce intestinal damage, reduce the content of malondialdehyde (MDA), and increase superoxide dismutase ( T-SOD) and glutathione (GSH) levels can effectively inhibit intestinal tissue peroxidation, indicating that fish swim bladder glycosaminoglycans can slow down intestinal damage through antioxidant effects.

As described above, the present invention can be better implemented. The above-mentioned embodiments are only descriptions of preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, ordinary people in the art can Various changes and improvements made by skilled personnel to the technical solution of the present invention should fall within the protection scope of the present invention.

Claims (5)

1. The application of the glycosaminoglycan in preparing the medicine for treating the intestinal injury is characterized in that the glycosaminoglycan is a swimming bladder glycosaminoglycan, and the preparation method of the swimming bladder glycosaminoglycan comprises the following steps: after the swimming bladder is subjected to enzymolysis by alkaline protease, centrifuging to obtain a supernatant, purifying and eluting by an anion exchange chromatographic column, and obtaining the swimming bladder glycosaminoglycan by adopting sodium chloride solutions with different concentrations as eluent;

the swimming bladder glycosaminoglycan is used for reducing the inflammation level in the blood of an organism, reducing the permeability of intestinal tracts, improving the shortening of the length of colon, improving the disorder of the crypt structure of colon, improving inflammatory infiltration and relieving oxidative stress damage of intestinal tracts.

2. The use according to claim 1, wherein the swimming bladder glycosaminoglycan is used at a concentration of 50mg/kg-200mg/kg for protecting intestinal lesions.

3. The use according to claim 1, wherein the alkaline protease enzymatic hydrolysis conditions are: drying and crushing swimming bladder, adding sodium chloride solution containing alkaline protease, wherein the solid-to-liquid ratio of the swimming bladder suspension is 1:10, the adding amount of sodium chloride is 6mg/mL, the adding amount of alkaline protease is 5.4mg/mL, stirring and enzymolysis for 20h in a water bath at 55 ℃, then inactivating enzyme, centrifuging at 4000rpm/min for 5min, and taking the supernatant to obtain a swimming bladder enzymolysis product.

4. The use according to claim 1, wherein the conditions for eluting the swim bladder glycosaminoglycan are: eluting with 0.3mol/L,0.9mol/L and 1.1mol/L sodium chloride solution, and adsorbing and purifying with Amberlite ™ FPA98Cl anion exchange chromatographic column as filler, wherein the swimming bladder glycosaminoglycan is a component obtained by eluting with 1.1mol/L sodium chloride solution.

5. A medicament for treating intestinal injury, which comprises the swimming bladder glycosaminoglycan as defined in claim 1 and pharmaceutically acceptable auxiliary materials.