An extract of Cordyceps sinensis with podocyte protection activity, its preparation method and application

Abstract

The present invention discloses a Cordyceps sinensis extract with podocyte protection activity, its preparation method and application. The preparation steps of the Cordyceps sinensis extract are as follows: 1) The dried powder of Cordyceps sinensis is successively extracted with n-hexane, ethyl acetate and absolute ethanol, and the medicinal residues are dried and then extracted with water to obtain an aqueous extract W1. After the aqueous extract W1 is subjected to deproteinization treatment, it is concentrated, and alcohol precipitation centrifugation is carried out to obtain alcohol precipitates W1CC to W4CC and an aqueous extract W2. 2) The aqueous extract W2 is purified by macroporous adsorption resin, eluted with a gradient of ethanol / water mixed solution, and the water-20% ethanol-water eluate is collected, concentrated and dried to obtain an extract W5CC. 3) The alcohol precipitate W1CC is compounded with the extract W5CC to obtain the Cordyceps sinensis extract. The Cordyceps sinensis extract of the present invention has the efficacy of reducing adriamycin-induced podocyte damage, its active ingredients are clear, and it can be used as a therapeutic drug for chronic kidney injury such as nephrotic syndrome, and has broad application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of medicine, and particularly relates to a Cordyceps sinensis extract with podocyte protection activity, a preparation method thereof, and an application thereof. Background Art

[0002] With the progress of medical technology and the improvement of living conditions, people's average life expectancy has been increasing continuously. However, at the same time, people are facing an increasingly severe problem of population aging. The kidney is an important organ that is vulnerable to structural and functional changes caused by the aging of the body, and the prevalence of chronic kidney disease (CKD) increases with age. The prevalence of CKD in the general population is 10% - 13%, but the prevalence of CKD in the elderly can reach 30% - 50%, which is a major chronic disease affecting the quality of life of the elderly. Approximately 8% - 16% of the global population suffers from CKD at different degrees, and about 10.8% of the people in China suffer from CKD, which is a serious disease endangering the health of humans, especially the elderly. Preventive intervention and gradually restoring kidney function through treatment are effective measures to solve the harm of chronic kidney disease to human physical and mental health.

[0003] Chronic kidney disease is a class of disease syndromes caused by primary or secondary kidney damage. Diabetic nephropathy (DN), primary glomerulonephritis, tubulointerstitial lesions, etc. are all the main pathogenic factors of chronic kidney disease. Podocytes are highly differentiated cells located on the glomerular basement membrane (GBM), and have functions such as maintaining the integrity of the glomerular basement membrane and the spatial structure of the capillary loop, and secreting vascular endothelial growth factor. A large number of studies have confirmed that the damage of podocytes plays an important role in chronic kidney diseases such as diabetic nephropathy, membranous nephropathy (MN), IgA nephropathy (IgAN), and focal segmental glomerulosclerosis (FSGS). Podocytes (glomerular epithelial cells) have been considered as the key cells in the progression of various chronic kidney diseases and also the key targets for the treatment of Chinese and Western medicines.

[0004] Cordyceps sinensis refers to the larval corpse and fungal stroma complex formed by the infection of the larvae of Hepialidae insects by Ophiocordyceps sinensis, which is a unique biological resource on the Qinghai-Tibet Plateau. In recent years, a large number of clinical trials and basic research reports have shown that Cordyceps sinensis protects the kidney through anti-inflammatory, antioxidant, and anti-hypoxia effects, demonstrating that Cordyceps sinensis has a positive therapeutic effect on the treatment of kidney damage caused by various factors, such as IgA nephropathy, chronic glomerulonephritis, diabetic nephropathy, chronic aristolochic acid nephropathy, and drug nephrotoxicity.

[0005] Cordyceps sinensis has various types of metabolites. Although a large number of reports have confirmed that Cordyceps sinensis has a certain therapeutic effect on chronic kidney disease, the specific active site or active ingredient is still unclear. In order to improve the therapeutic efficacy of Cordyceps sinensis on chronic kidney disease and develop a preparation for chronic kidney disease with clear active ingredients and controllable quality, the present invention discloses a preparation method and application of an extract of Cordyceps sinensis with podocyte protection activity.

[0006] The extract of Cordyceps sinensis with podocyte protection activity prepared by the present invention has a simple preparation process, low cost, remarkable activity, easy quality control, and is of great significance for the development and utilization of preparations for treating chronic kidney disease with Cordyceps sinensis. Summary of the Invention

[0007] One of the purposes of the present invention is to provide an extract of Cordyceps sinensis with podocyte protection activity, which can be used for the development of pharmaceutical preparations for treating chronic kidney disease.

[0008] Another purpose of the present invention is to provide a preparation method of the above-mentioned extract of Cordyceps sinensis.

[0009] To achieve the above purposes, the present invention adopts the following technical solutions:

[0010] A preparation method of an extract of Cordyceps sinensis with podocyte protection activity includes the following steps:

[0011] (1) Fresh medicinal materials of Cordyceps sinensis are dried to constant weight, pulverized, and successively extracted with n-hexane, ethyl acetate, and absolute ethanol. The medicinal residues are dried for later use. The medicinal residues of Cordyceps sinensis are added with water for extraction to obtain a water extract W1. After the water extract W1 is deproteinized and concentrated, a concentrated solution is obtained. The concentrated solution is fractionated by alcohol precipitation, placed at low temperature to precipitate, and centrifuged to obtain alcohol precipitates W1CC to W4CC with different ethanol concentrations and the Cordyceps sinensis water extract W2 after removing the precipitate.

[0012] (2) The Cordyceps sinensis water extract W2 is purified by macroporous adsorption resin, gradient eluted with an ethanol / water mixture, the eluate is collected, concentrated and dried to obtain an extract of Cordyceps sinensis W5CC.

[0013] (3) The alcohol precipitate W1CC and the extract W5CC are mixed in a certain proportion to obtain an extract of Cordyceps sinensis WS with podocyte protection activity.

[0014] Preferably, in step (1), when successively extracting with n-hexane, ethyl acetate, and absolute ethanol, the material-liquid ratio used is 1:5 to 10, the extraction times are all 3 times, and the extraction methods are all ultrasonic or reflux; when adding water for extraction, the material-liquid ratio used is 1:5 to 10, the extraction times are 3 times, and the extraction method is ultrasonic or reflux.

[0015] Preferably, in step (1), the protein removal treatment is to mix the aqueous extract W1 of Cordyceps sinensis with an equal volume of a dichloromethane-n-butanol mixed solution, shake vigorously to remove protein, and repeat the protein removal 10 times. In the dichloromethane-n-butanol mixed solution, dichloromethane: n-butanol = 1:1 to 3, by volume ratio. Preferably, dichloromethane: n-butanol = 1:1, by volume ratio.

[0016] Preferably, in step (1), the concentration is to concentrate to a density of 1.0 g / mL to 1.1 g / mL. More preferably, it is concentrated to a density of 1.02 g / mL.

[0017] Preferably, in step (1), the preparation steps of the alcohol precipitates W1CC to W4CC are as follows: First, add ethanol to the concentrated solution until the ethanol concentration is 20%, place it at 4°C for 12 h to precipitate, centrifuge to obtain precipitate W1CC, then continue to add ethanol until the ethanol concentration is 40%, place it at 4°C for 12 h to precipitate, centrifuge to obtain precipitate W2CC, then continue to add ethanol until the ethanol concentration is 60%, place it at 4°C for 12 h to precipitate, centrifuge to obtain precipitate W3CC, then continue to add ethanol until the ethanol concentration is 80%, place it at 4°C for 12 h to precipitate, centrifuge to obtain precipitate W4CC and the aqueous extract W2 of Cordyceps sinensis after removing the precipitate.

[0018] Preferably, in step (2), the macroporous resin is one of AB-8, D-101, D301, HP-20, S-8, X-5, XAD-1, XAD-4, H-103. More preferably, the macroporous resin is one of AB-8, D-101, HP-20, D301.

[0019] Preferably, in step (2), the gradient elution is carried out with an ethanol / water volume ratio of 0:100 to 80:20; the eluent is collected with an ethanol / water volume ratio of 0:100 to 20:80.

[0020] Preferably, in step (2), the loading concentration of the sample is 1.01 g / mL, and the elution rate is 3 BV / h.

[0021] Preferably, in step (2), the concentration refers to reduced pressure concentration at a temperature of 60°C, and the drying refers to reduced pressure vacuum drying, freeze drying or spray drying.

[0022] Preferably, in step (2), the final concentration of the concentrated solution is 1.2 g / mL, and the reduced pressure vacuum drying temperature is 60°C.

[0023] Preferably, in step (3), the alcohol precipitate W1CC and the extract W5CC are mixed in a mass ratio of 1:1 to 50. More preferably, the alcohol precipitate W1CC and the extract W5CC are mixed in a mass ratio of 1:25 to 50.

[0024] Preferably, in step (2), the high performance liquid chromatography fingerprint of the Cordyceps sinensis extract W5CC contains four active pharmaceutical ingredients, namely adenosine, inosine, guanosine and thymine.

[0025] Preferably, in the said step (2), the chromatographic conditions of the high performance liquid chromatography fingerprint of the Cordyceps sinensis extract W5CC are as follows:

[0026] Mobile phase: Using ultrapure water as phase A and acetonitrile as phase B for gradient elution. The mobile phase gradient conditions are as follows: 0 - 10 min, in the mobile phase, A (100% → 100%), B (0% → 0%); 10 - 25 min, in the mobile phase, A (100% → 90%), B (0% → 10%); 25 - 30 min, in the mobile phase, A (90% → 80%), B (10% → 20%); 30 - 35 min, in the mobile phase, A (80% → 100%), B (20% → 0%); 35 - 40 min, in the mobile phase, A (100% → 100%), B (0% → 0%);

[0027] Chromatographic column: C18 chromatographic column, preferably InfinityLab Poroshell 120EC - C18, specification: 4.6×100mm, 2.7 Micron.

[0028] Flow rate: 0.5 mL / min;

[0029] Column temperature: 30°C

[0030] Detection wavelength: 227 nm.

[0031] The present invention also provides a Cordyceps sinensis extract with podocyte protection activity prepared according to the above preparation method.

[0032] The present invention also provides the application of the above Cordyceps sinensis extract in the preparation of drugs and / or health products for protecting podocytes.

[0033] The present invention also provides the application of the above Cordyceps sinensis extract in the preparation of drugs and / or health products for preventing and treating chronic kidney diseases.

[0034] Preferably, the final use concentration of the Cordyceps sinensis extract WS is 50 - 500 μg / mL.

[0035] The present invention also provides a drug and / or health product for protecting podocytes or preventing and treating chronic kidney diseases, which contains the above Cordyceps sinensis extract as an active ingredient.

[0036] Compared with the prior art, the present invention has the following advantages:

[0037] 1. An extract of Cordyceps sinensis with podocyte protection activity according to the present invention can effectively reduce the damage of mouse podocyte cell line MPC5 induced by Adriamycin (ADM), improve the growth rate of podocyte MPC5, and purify and remove impurities from the active components of Cordyceps sinensis with podocyte protection activity under the guidance of an active model. Stimulating podocytes with Adriamycin can induce podocyte apoptosis and cause chronic damage. Podocytes are the outermost barrier of the glomerular basement membrane. If podocytes are damaged, the glomerular filtration function will decline, resulting in proteinuria. Chronic kidney disease is the main factor causing podocyte damage. Protecting podocytes, reducing podocyte damage and promoting podocyte regeneration are the main ways to treat chronic kidney disease. The present invention is based on an in vitro model of Adriamycin-induced damage of mouse podocyte MPC5, and evaluates the protective effect of Cordyceps sinensis extract on podocytes by detecting the inhibition rate of Adriamycin on podocyte growth after adding Cordyceps sinensis extract.

[0038] 2. An extract of Cordyceps sinensis with podocyte protection activity according to the present invention belongs to a complex of two different active parts of Cordyceps sinensis. Through the proportionate use of two different active parts, the activity is enhanced compared with the single use. Further analysis reveals that the active part W1CC mainly contains macromolecular polysaccharide compounds, and the HPLC fingerprint of the active part W5CC mainly contains five active components, and four of them have been identified, providing an effective method for the quality control of Cordyceps sinensis extract.

[0039] 3. The present invention obtains extracts with different polarities by using solvents with various polarities, combines an active screening model, removes inactive components, and finally obtains an extract of Cordyceps sinensis with significant activity. The extraction and concentration methods are efficient, and the extraction method is relatively stable and the quality is controllable, providing a reference for mass production and wide promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is the HPLC fingerprint of Cordyceps sinensis extract W5CC (Peak 1: Inosine; Peak 2: Guanosine; Peak 3: Unknown compound; Peak 4: Thymine; Peak 5: Adenosine).

[0041] Figure 2 It is the picture of podocyte growth (Model group: Treatment with Adriamycin but without sample added; WS group: Treatment with both Adriamycin and Cordyceps sinensis extract WS sample added). DETAILED DESCRIPTION OF THE INVENTION

[0042] The following examples are further illustrations of the present invention, rather than limitations on the present invention.

[0043] Example 1

[0044] A preparation method of a Cordyceps sinensis extract with podocyte protection activity, comprising the following steps:

[0045] Select 50 g of artificially cultivated Cordyceps sinensis as raw material, freeze-dry it to constant weight and then crush it, pass through a 10-mesh sieve to obtain the crude powder of Cordyceps sinensis. Add 500 mL of n-hexane solvent to the crude powder of Cordyceps sinensis, and perform ultrasonic extraction. The power used for ultrasonic extraction is 400 W, the working frequency is 40 KHz, the extraction time is 15 min, and extract 3 times to obtain 2.51 g of n-hexane extract (yield 5.02%). Place the Cordyceps sinensis residue at room temperature, volatilize the n-hexane solvent and set aside; add 500 mL of ethyl acetate solvent to the Cordyceps sinensis residue, and perform ultrasonic extraction. The power used for ultrasonic extraction is 400 W, the working frequency is 40 KHz, the extraction time is 15 min, and extract 3 times to obtain 0.75 g of ethyl acetate extract (yield 1.50%). Place the Cordyceps sinensis residue at room temperature, volatilize the ethyl acetate solvent and set aside; add 500 mL of absolute ethanol solvent to the Cordyceps sinensis residue, and perform ultrasonic extraction. The power used for ultrasonic extraction is 400 W, the working frequency is 40 KHz, the extraction time is 15 min, and extract 3 times to obtain 0.89 g of absolute ethanol extract (yield 1.79%). Place the Cordyceps sinensis residue at room temperature, volatilize the absolute ethanol solvent and set aside; add 500 mL of water to the Cordyceps sinensis residue, heat under reflux for extraction, the extraction time is 30 min, and extract 3 times to collect the aqueous extract W1 of Cordyceps sinensis. Add an equal volume of dichloromethane-n-butanol (1:1, volume ratio) mixed solvent to the aqueous extract W1 of Cordyceps sinensis, shake vigorously to precipitate proteins and then let it stand for precipitation, centrifuge to remove the precipitate, and repeat the protein removal 10 times. The Cordyceps sinensis extract W1 after protein removal is concentrated under reduced pressure at 60 °C to a density of 1.02 g / mL. Add ethanol to the concentrated solution of W1 to make the alcohol content 20%, place it in a 4 °C refrigerator for 12 h, and centrifuge to obtain 0.41 g of 20% alcohol precipitate (W1CC, yield 0.82%). Continue to add ethanol to make the alcohol content 40%, place it in a 4 °C refrigerator for 12 h, and centrifuge to obtain 0.39 g of 40% alcohol precipitate (W2CC, yield 0.78%). Continue to add ethanol to make the alcohol content 60%, place it in a 4 °C refrigerator for 12 h, and centrifuge to obtain 0.72 g of 60% alcohol precipitate (W3CC, yield 1.44%). Continue to add ethanol to make the alcohol content 80%, place it in a 4 °C refrigerator for 12 h, and centrifuge to obtain 1.18 g of 80% alcohol precipitate (W4CC, yield 2.36%) and the aqueous extract W2 of Cordyceps sinensis after removing the precipitate.

[0046] The aqueous extract of Cordyceps sinensis W2 was concentrated until it had no alcohol smell, and then its density was adjusted to 1.01 g / mL. It was added to a 100 g AB-8 macroporous resin column and eluted at a flow rate of 3 BV / h with gradient elution. The eluents were water, 20% ethanol / water, 40% ethanol / water, 60% ethanol / water, and 80% ethanol / water in sequence. Each eluent was used to elute with 3 column volumes of solvent. The eluate of water-20% ethanol / water was collected, concentrated under reduced pressure to 1.2 g / mL at 60 °C, and dried to constant weight under reduced pressure and vacuum at 60 °C to obtain Cordyceps sinensis extract W5CC, with a yield of 11.8%. The fingerprint of Cordyceps sinensis extract W5CC was determined by high performance liquid chromatography. The detection wavelength was 227 nm, the column temperature was 30 °C, the flow rate was 0.5 mL / min. The chromatographic column was preferably InfinityLab Poroshell 120 EC-C18, with specifications: 4.6×100 mm, 2.7 Micron. The mobile phase gradient program was as follows: using ultrapure water as phase A and acetonitrile as phase B. From 0 to 10 min, in the mobile phase, A (100%→100%), B (0%→0%); from 10 to 25 min, in the mobile phase, A (100%→90%), B (0%→10%); from 25 to 30 min, in the mobile phase, A (90%→80%), B (10%→20%); from 30 to 35 min, in the mobile phase, A (80%→100%), B (20%→0%); from 35 to 40 min, in the mobile phase, A (100%→100%), B (0%→0%). The fingerprint contains four active pharmaceutical ingredients, adenosine, inosine, guanosine, and thymine ( Figure 1 ). The 20% ethanol precipitation product W1CC and the extract W5CC were mixed evenly according to the mass ratio of 1:50 to obtain the complex WS of two active parts.

[0047] Example 2

[0048] Detection of the podocyte protection activity of Cordyceps sinensis extract:

[0049] 1. Reagents and instruments

[0050] Mouse podocyte cell line MPC5; doxorubicin hydrochloride (ADM); high-glucose DMEM medium; fetal bovine serum (FBS); phosphate buffer solution (PBS); dimethyl sulfoxide (DMSO); 1% P / S double antibody; Cell counting kit 8 (cck8); precision electronic balance; biological safety cabinet; carbon dioxide incubator; inverted microscope; low-speed refrigerated centrifuge; microplate reader; digital display constant temperature water bath.

[0051] 2. Culture of MPC5 cells

[0052] The basic culture medium was DMEM culture solution + 10% FBS + 1% P / S double antibody; the culture conditions were 37 °C, 5% CO2 and saturated humidity; The cell density can reach 90% after culturing for 2 - 3 days and can be used for experiments.

[0053] 3. Effect of Cordyceps sinensis extract on cell growth rate

[0054] Adjust the density of well - conditioned podocytes to 5×10 3 cells / mL, inoculate them into a 96 - well plate (6 replicates per group, 100 μL per well), and culture at 37°C and 5% CO 2 in an incubator for 24 h. Discard the original medium, and set up a normal group, a model group, and a sample group. The medium in the normal group does not add doxorubicin hydrochloride and the sample. The model group adds doxorubicin hydrochloride solution (final concentration 0.2 μg / mL) to the medium. The sample group adds doxorubicin hydrochloride (final concentration 0.2 μg / mL) and Cordyceps sinensis extract (final concentration is shown in Table 1) to the medium. The added amount of the medium is 100 μL. Set 6 replicates for each group. After culturing for 24 h, add 10 μL of cck8 reagent to each well, incubate at 37°C for 2 h, and use an enzyme - linked immunosorbent assay (ELISA) reader to detect the absorbance value of each well. Calculate the inhibition rate according to the formula.

[0055] Cell inhibition rate = 1 - (absorbance of the drug - added well - background value) / (absorbance of the control well - background value)×100%

[0056] The experimental data were analyzed by one - way analysis of variance using SPSS 22.0 statistical software for significant difference analysis. p < 0.05 indicates a significant difference and is statistically significant.

[0057] 4. Data analysis

[0058] The effects of different treatments on the growth of mouse podocyte MPC5 are shown in Figure 2 and Table 1.

[0059] As can be seen from Table 1, the growth rate of mouse podocyte MPC5 decreased significantly under the action of doxorubicin, showing a significant difference compared with the cell growth rate of the normal group, indicating that the cell model was successfully established. The 20% ethanol - precipitated product (W1CC) and Cordyceps sinensis extract W5CC both showed certain podocyte - protecting activities at a concentration of 500 μg / mL. The 40% ethanol - precipitated product (W2CC), 60% ethanol - precipitated product (W3CC), and 80% ethanol - precipitated product (W4CC) did not detect podocyte - protecting activities at three concentrations. The complex WS of the 20% ethanol - precipitated product (W1CC) and Cordyceps sinensis extract W5CC showed significant growth - promoting activities on doxorubicin - induced damaged podocytes, reducing the damage effect of doxorubicin on podocytes to a certain extent. The Cordyceps sinensis extract WS obtained by the technology of the present invention showed stronger podocyte - protecting activities and presented a dose - effect relationship.

[0060] Table 1 Effect of Cordyceps sinensis extract on the growth rate of doxorubicin - induced damaged podocytes

[0061]

[0062]

[0063] Note: * indicates significant difference compared with the model group (p < 0.05);

[0064] ** indicates obvious significant difference compared with the model group (p < 0.01).

[0065] A Cordyceps sinensis podocyte-protective active extract of the present invention can effectively inhibit the damage caused by adriamycin to podocytes, effectively improve the growth rate of adriamycin-damaged podocytes, exhibit significant podocyte-protective activity, and under the guidance of an activity model, purify and remove impurities from the Cordyceps sinensis podocyte-protective active substances. Stimulating podocytes with adriamycin to cause chronic damage to podocytes can simulate the damage to renal podocytes caused by various chronic kidney diseases such as diabetic nephropathy, membranous nephropathy (MN), IgA nephropathy (IgAN), and focal segmental glomerulosclerosis (FSGS). Podocytes have been regarded as the key cells in the progression of various chronic kidney diseases. The present invention is based on an in vitro model of adriamycin-induced chronic damage to podocyte MPC5, and evaluates the protective activity of Cordyceps sinensis extract on podocytes by detecting the effect of Cordyceps sinensis extract on the growth rate of podocytes after adriamycin stimulation. A preparation method of a Cordyceps sinensis podocyte-protective active extract of the present invention obtains an extract with significant podocyte-protective activity by steps such as purification, separation, and concentration, and combining active parts into a complex, further interprets the pharmacodynamic basis of Cordyceps sinensis in treating various chronic kidney diseases, and the extraction and concentration methods are efficient, and the extract is relatively stable and the quality is controllable.

[0066] The above are only the preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. For those of ordinary skill in the art in this technical field, without departing from the spirit and scope of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. Preparation method of cordyceps sinensis extract with activity of treating podocyte injury caused by chronic kidney disease, characterized in that, it comprises the following steps: (1) Fresh cordyceps sinensis medicinal materials are dried to constant weight, pulverized, and successively extracted with n-hexane, ethyl acetate and absolute ethanol. The medicinal residues are dried for standby. The cordyceps sinensis medicinal residues are added with water for extraction to obtain water extract W1. After the water extract W1 is subjected to deproteinization treatment and concentrated, a concentrated solution is obtained. First, ethanol is added to the concentrated solution until the ethanol concentration is 20%, and it is left at 4 °C for 12 h to precipitate. After centrifugation to obtain precipitate W1CC, ethanol is continuously added until the ethanol concentration is 40%, and it is left at 4 °C for 12 h to precipitate. After centrifugation to obtain precipitate W2CC, ethanol is continuously added until the ethanol concentration is 60%, and it is left at 4 °C for 12 h to precipitate. After centrifugation to obtain precipitate W3CC, ethanol is continuously added until the ethanol concentration is 80%, and it is left at 4 °C for 12 h to precipitate. After centrifugation to obtain precipitate W4CC and the cordyceps sinensis water extract W2 after removing the precipitate; (2) The cordyceps sinensis water extract W2 is purified by macroporous adsorption resin, and gradient elution is carried out with an ethanol / water mixture in a volume ratio of 0:100 to 80:

20. The eluate of water-20% ethanol / water is collected, concentrated and dried to obtain cordyceps sinensis extract W5CC; (3) The alcohol-precipitated product W1CC and the extract W5CC are mixed in a mass ratio of 1:50 to obtain cordyceps sinensis extract WS with activity of treating podocyte injury caused by chronic kidney disease.

2. The preparation method according to claim 1, characterized in that, in step (1), when successively extracting with n-hexane, ethyl acetate and absolute ethanol, the material-liquid ratio used is 1:5 to 10, and the extraction methods are all ultrasonic or reflux; when adding water for extraction, the material-liquid ratio used is 1:5 to 10, and the extraction method is ultrasonic or reflux.

3. The preparation method according to claim 1, characterized in that, in step (1), the concentration is concentrated to a density of 1.0 g / mL to 1.1 g / mL.

4. Cordyceps sinensis extract with activity of treating podocyte injury caused by chronic kidney disease prepared by the preparation method according to any one of claims 1-3.

5. Application of the cordyceps sinensis extract according to claim 4 in the preparation of a drug for treating podocyte injury caused by chronic kidney disease.

6. A drug for treating podocyte injury caused by chronic kidney disease, characterized in that, it contains the cordyceps sinensis extract according to claim 4 as an active ingredient.

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