Active peptide for inhibiting ferroptosis and application thereof

Abstract

The invention is applicable to the technical field of biology, and provides an active peptide for inhibiting ferroptosis and application thereof, and the amino acid sequence of the active peptide is as shown in SEQ ID No.1. The active peptide for inhibiting ferroptosis provided by the invention is derived from walnuts, and compared with a ferroptosis inhibitor reported at present, the active peptide for inhibiting ferroptosis is high in activity and free of obvious side effects; in-vitro and animal model tests prove that the bioactive peptide has anti-inflammatory activity, can significantly down-regulate cis-platinum induced iron ion overload, reduce the number of ferroptosis mitochondria and improve AKI and related metabolic indexes, and can be applied to preparation of drugs for preventing or treating AKI.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of biotechnology, and particularly relates to an active peptide for inhibiting ferroptosis and application thereof. BACKGROUND

[0002] Acute kidney injury (AKI) is a clinical syndrome characterized by rapid deterioration of renal function, and has a high incidence in intensive care unit patients. AKI not only leads to prolonged hospitalization and increased medical costs, but is also closely related to the development of chronic kidney disease and end-stage renal disease, which seriously threatens the quality of life and survival rate of patients. AKI can be caused by various factors, including chemical drugs, toxins, ischemia, infection, and surgical trauma. Drug-related nephrotoxicity is one of the main causes of AKI, including antibacterial agents (such as aminoglycosides), anticancer drugs (such as cisplatin), analgesics (such as non-steroidal anti-inflammatory drugs), and immunosuppressive agents (such as cyclosporine). At present, the clinical treatment of AKI mainly relies on supportive interventions, including correcting hypovolemia, discontinuing nephrotoxic drugs, and renal replacement therapy. However, these methods can only temporarily alleviate symptoms and cannot fundamentally block the progression of kidney damage. Therefore, developing new strategies to improve AKI has become a pressing problem.

[0003] Ferroptosis is a form of iron-dependent programmed cell death, and its essence is the abnormal accumulation of phospholipid peroxides leading to the disintegration of cell membrane structure. Its core mechanism involves decreased glutathione peroxidase 4 (GPX4) activity, increased iron ion levels, and accumulation of lipid peroxidation products. Ferroptosis is closely related to various diseases such as neurodegenerative diseases and cardiovascular diseases. In cisplatin-induced AKI models, the level of ferroptosis in renal tubular epithelial cells is significantly increased, and ferroptosis inhibitors can effectively improve renal function by inhibiting lipid peroxidation and regulating iron metabolism-related genes (such as TFR1 and FPN1). Currently reported ferroptosis inhibitors are mainly derived from synthetic compounds, and there are few reports on naturally derived ferroptosis inhibitors. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide an active peptide for inhibiting ferroptosis, which aims to solve the problems raised in the background art.

[0005] The embodiments of the present application are implemented as follows: an active peptide for inhibiting ferroptosis, wherein the amino acid sequence of the active peptide is Phe-Gly-Met-Pro-Pro-Cys-Leu (FGMPPCL), as shown in SEQ ID No. 1.

[0006] Another purpose of the embodiments of the present application is to provide an application of the active peptide for inhibiting ferroptosis in preparing a ferroptosis inhibitor.

[0007] Another object of the present application is to provide an application of the active peptide for inhibiting ferroptosis in the preparation of a medicine for preventing or treating AKI.

[0008] The active peptide for inhibiting ferroptosis provided by the present application is derived from walnut protein hydrolysate, has high activity and no obvious side effects compared with the currently reported ferroptosis inhibitors.

[0009] The active peptide has anti-inflammatory activity, can significantly down-regulate cisplatin-induced iron overload, reduce the number of ferroptosis mitochondria, improve AKI and related metabolic indicators, and can be applied to the preparation of a medicine for preventing or treating AKI. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 A schematic diagram of the influence of the active peptide FGMPPCL provided in Embodiment 2 of the present application on tumor necrosis factor-alpha (TNF-alpha); Figure 2 A schematic diagram of the influence of the active peptide FGMPPCL provided in Embodiment 2 of the present application on interleukin-6 (IL-6); Figure 3 A schematic diagram of the influence of the active peptide FGMPPCL provided in Embodiment 2 of the present application on interferon-gamma (IFN-gamma); Figure 4 A kidney tissue iron content analysis chart provided in Embodiment 3 of the present application; Figure 5 A representative Western blotting chart provided in Embodiment 4 of the present application; Figure 6 A FTH1 Western blotting quantitative analysis provided in Embodiment 4 of the present application; Figure 7 A GPX4 Western blotting quantitative analysis provided in Embodiment 4 of the present application; Figure 8 An xCT Western blotting quantitative analysis provided in Embodiment 4 of the present application; Figure 9 Transmission electron microscope analysis results of the ultrastructure of mouse kidney tissue provided in Embodiment 5 of the present application (a is the result of the control group, b is the result of the model group, and c is the result of the FGMPPCL intervention group); Figure 10 A schematic diagram of the influence of the active peptide FGMPPCL provided in Embodiment 6 of the present application on the serum biochemical index urea nitrogen (BUN) of mice; Figure 11 A schematic diagram of the influence of the active peptide FGMPPCL provided in Embodiment 6 of the present application on the serum biochemical index creatinine (Scr) of mice; Figure 12The mouse kidney HE staining provided for the embodiment 7 of the present application represents a graph (a is the result of the control group, b is the result of the model group, c is the result of the FGMPPCL intervention group; wherein black represents glomerulus; yellow represents renal tubule); Figure 13 The immunofluorescence provided for the embodiment 8 of the present application represents a graph; Figure 14 The KIM-1 immunofluorescence quantitative analysis provided for the embodiment 8 of the present application; Figure 15 The NGAL immunofluorescence quantitative analysis provided for the embodiment 8 of the present application. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0012] The specific implementation of the present application is described in detail below in combination with specific embodiments.

[0013] The embodiment 1, the solid phase synthesis method of the active peptide FGMPPCL, includes the following steps: Solid phase synthesis: take Fmoc-Leu-Wang Resin, soak and swell with dichloromethane (DCM), then dry, add cap removal liquid to remove Fmoc protecting group, wash, and then add Fmoc-Cys (Trt)-OH, Fmoc-Pro-OH, Fmoc-Pro-OH, Fmoc-Met-OH, Fmoc-Gly-OH, Fmoc-Phe-OH for condensation reaction, wash after each condensation, and then add the last amino acid (Fmoc-Phe-OH), remove the N-terminal Fmoc protecting group again using cap removal liquid and wash; Cutting and purification: trifluoroacetic acid (TFA) cutting solution was added to the resin for cutting reaction, the lysis solution was filtered out, the resin was washed with a small amount of TFA, the filtrates were combined, the obtained crude peptide solution was concentrated, precipitated with ether, the precipitate was collected by centrifugation and dried to obtain a crude product, a small amount of the crude product was taken for mass spectrometry (MS) analysis to confirm the target molecular weight, about 1 mg of the crude product was completely dissolved, an analytical HPLC (mobile phase A: 0.1% TFA / H2O, B: 0.1% TFA / ACN) was used to determine the target peptide main peak retention time under a 10-100% B gradient, and the gradient program of a preparative HPLC (Beijing Innovative Technology CXTH-3000 liquid chromatography system) was set according to the retention time, the remaining crude product was dissolved, filtered and injected, and the prepared system (mobile phase A: H2O, B: ACN) was started after being balanced, and the correct target peptide main peak fraction was collected according to the set gradient and mass spectrometry confirmation, the qualified fractions were combined, most of the acetonitrile was removed by rotary evaporation under reduced pressure, the remaining aqueous solution was freeze-dried to obtain the purified target peptide FGMPPCL.

[0014] Example 2, determination of anti-inflammatory activity of active peptide FGMPPCL: The experimental groups included control, model and active peptide intervention groups, PC12 cell suspension was prepared at 1×10 5The cells were plated at a concentration of 1 x 105cells / mL, inoculated in six-well cell culture plates (2 mL final volume per well), and incubated at 37°C in a 5% CO2incubator for 24 h. The control group was added with 1640 complete culture medium, and the model group was replaced with 1 μg / mL LPS-1640 solution after being cultured in 1640 complete culture medium for 24 h and then cultured for another 24 h. The active peptide intervention group was replaced with 1 μg / mL LPS-1640 solution after being cultured in 100 μM active peptide 1640 complete culture medium for 24 h and then cultured for another 24 h. After the cell culture was completed, the supernatant samples were collected from each well, centrifuged at 12,000 r / min for 10 min to remove cell debris, and the concentration levels of proinflammatory mediators (TNF-α, IL-6, and INF-γ) were quantitatively detected according to the operation specification of the rat interleukin (IL-6), gamma interferon (INF-γ), and tumor necrosis factor (TNF-α) ELISA detection kit (purchased from Nanjing Jiancheng Bioengineering Institute). Standard sample wells and sample wells were set up, 50 L of standard samples with different concentrations were added to each standard sample well, 10 μL of the sample to be tested was added to each sample well, and then 40 μL of sample diluent was added. No blank well was added. Except for the blank well, 100 μL of horseradish peroxidase (HRP)-labeled detection antibody was added to each of the standard sample wells and sample wells. The reaction wells were sealed with a sealing film, incubated in a 37°C water bath or incubator for 60 min, the liquid was discarded, and the wells were dried on a blotting paper. The wells were filled with washing solution, left to stand for 1 min, and the washing solution was discarded. The wells were dried on a blotting paper, and the process was repeated 5 times. 50 μL of substrate A and B was added to each well, and the mixture was incubated at 37°C in the dark for 15 min. 50 μL of stop solution was added to each well, and the OD value of each well was measured at 450 nm within 15 min. The results are shown in Figures 1 to 3 As can be seen, when the concentration of the active peptide FGMPPCL was 100 μM, the content of inflammatory factors in LPS-induced PC12 cells was significantly reduced. The content of TNF-α was reduced from 167.61 pg / mL to 79.96 pg / mL, the content of IL-6 was reduced from 154.38 pg / mL to 91.75 pg / mL, and the content of IFN-γ was reduced from 258.04 pg / mL to 192.25 pg / mL.

[0015] Example 3: Determination of the reduction of iron ion content by the active peptide FGMPPCL The animal study was approved by the Ethics Committee of Jilin Agricultural University and followed the Guidelines for the Care and Use of Laboratory Animals published by the European Commission. Male C57BL / 6J mice (18-20 g) were purchased from Huafukang Biotechnology Co., Ltd. (Beijing, China) and were raised in the Experimental Animal Center of Jilin Agricultural University at a constant temperature (20 ± 2°C) with a 12 h light / dark cycle and free access to food and water. After acclimating to the indoor environment for 1 week, the mice were randomly divided into 3 groups (n=6): (I) control group: daily gavage with normal saline for 28 consecutive days; (II) model group: daily gavage with normal saline, injection of cisplatin at a concentration of 20 mg / kg on the 25th day, and sacrificed 72 hours after injection; (III) active peptide intervention group: daily gavage with FGMPPCL solution at a concentration of 80 mg / kg, injection of cisplatin at a concentration of 20 mg / kg on the 25th day, and sacrificed 72 hours after injection; Strictly follow the procedure of the rat iron content (ferrozine colorimetric method) detection kit (purchased from Addison Biotechnology Co., Ltd.): approximately 0.1 g of kidney tissue was added to 1 mL of the extract, homogenized on ice, and centrifuged at 12,000 rpm for 5 min at 4°C. The supernatant was collected and placed on ice for testing. Preheat the microplate reader for 30 minutes, set the wavelength to 562 nm, thaw all reagents to room temperature, and divide them into three groups: assay tubes, standard tubes, and blank tubes. For samples, add 120 μL to the assay tubes, but not to the standard tubes or blank tubes. For standards, add 120 μL to the standard tubes, but not to the assay tubes or blank tubes. For distilled water, add 120 μL to the blank tubes, but not to the assay tubes or standard tubes. For reagent 1, add 260 μL to the assay tubes, standard tubes, and blank tubes. For reagent 2, add 20 μL to the assay tubes, standard tubes, and blank tubes. After adding the sample, mix thoroughly and let it stand at room temperature for 15 minutes. If the solution is turbid, centrifuge at 3000 rpm for 5 minutes, take 200 μL of the supernatant to a 96-well plate, and measure the absorbance A at a wavelength of 562 nm (if the absorbance A of the measurement tube is greater than 0.8, dilute the sample supernatant with distilled water and substitute the dilution factor D into the calculation formula). This will be used in subsequent experimental steps such as calculating the content of the target component in the sample by absorbance. Calculated according to tissue mass: ; Where, D is the dilution multiple; W is the sample mass; is the absorbance of the measuring tube; is the absorbance of the blank tube; The result is as follows Figure 4 As shown in the figure, it can be seen that the iron content of the model group (cisplatin-treated group) was 32.60 ± 1.73 μg / g, which was significantly higher than that of the control group (26.42 ± 0.70 μg / g). P <0.05), while the iron content in the FGMPPCL group was 20.71 ± 2.76 μg / g ( P <0.05), the iron ion content in the rats was significantly lower than that in the model group, indicating that FGMPPCL has the ability to reduce the iron ion content.

[0016] Example 4: Determination of the ability of the active peptide FGMPPCL to regulate ferroptosis core protein: The experimental animals were grouped and treated as in Example 3. Subsequently, 30 mg of kidney tissue was quickly collected on ice, 300 μL of RIPA lysis buffer containing the protease inhibitor PMSF (1:100) was added, and the tissue was quickly ground on ice for 20 min. Subsequently, the tissue was centrifuged at 12,000 rpm for 10 min in a 4°C centrifuge. The supernatant was collected into an EP tube and the protein concentration was determined using the BCA method. The specific procedure for protein immunoblotting is as follows: Electrophoresis: Prepare 8-12% separation gel according to the molecular weight of the target protein. Run at 80 V for 20 min, then adjust to 120 V for 90 min or 250 V for 30 min. Cut the gel according to the molecular weight of the target protein, cut the 0.45 μm PVDF into strips according to the size of the gel strip, activate it in 100% anhydrous ethanol for 10 seconds, and then put it into the wet transfer solution. Place it in the order of "black clips-transfer sponge-gel-PVDF membrane-transfer sponge-white clips" from bottom to top to avoid bubbles. Place it in the wet transfer tank and set different transfer times and currents according to the molecular weight according to the instructions; After transfer, the PVDF membrane was placed in an antibody incubation box and washed three times with TBST, each time for 10 min. After washing, the membrane was blocked in 5% skim milk at room temperature for 60 min. After blocking, the PVDF membrane was washed three times with TBST for 5 min each time, and the primary antibody was diluted to different concentrations using 3% skim milk powder according to the antibody instructions and incubated with the PVDF membrane at 4°C overnight; The next day, the PVDF membrane was washed three times with TBST for 5 min each time, and HRP-labeled IgG secondary antibody was added and incubated at room temperature for 60 min; then washed three times with TBST for 5 min each time; ECL color development: gel imaging was performed using ECL luminescent solution and photographed, and Image J software was used for band grayscale analysis; The result is as follows Figures 5 to 8 As shown in the figure, it can be seen that compared with the blank group, cisplatin treatment can significantly downregulate the expression levels of ferroptosis-related proteins ( P <0.05); the relative expression levels of FTH1, GPX4 and xCT proteins in the model group decreased to 1.59 ± 0.07, 1.60 ± 0.13 and 2.57 ± 0.36, respectively, indicating that cisplatin induced ferroptosis, while after FGMPPCL intervention, the expression of the three proteins was significantly upregulated ( P<0.05), wherein FTH1 increased to 2.18 ± 0.31, GPX4 increased to 2.39 ± 0.21, and xCT increased to 3.93 ± 0.22, indicating that the expression levels of the three proteins were significantly restored after FGMPPCL intervention.

[0017] Example 5, Active Peptide FGMPPCL Improves Cell Ferroptosis Morphology: The experimental animals were grouped and treated as in Example 3, and then the kidneys of the mice after rapid euthanasia on ice were placed in a 1.5 mL centrifuge tube, fixed in 2.5% glutaraldehyde fixative at 4°C overnight, and the fixative was completely immersed in the sample. After fixation, the glutaraldehyde solution was discarded, and the sample was washed with 0.1 M phosphate buffer at pH 7.0 for about 15 min each time, and then transferred to a 1% osmium acid solution for secondary fixation for 1-2 hours, and then washed with phosphate buffer for three times. The sample was dehydrated by gradient ethanol method, and sequentially treated with 30%, 50%, 70%, 80%, 90% and 95% ethanol solution for 15 min each time, and finally treated with anhydrous ethanol for 20 min to complete dehydration. The dehydrated sample was transferred to pure acetone for replacement for 20 min to prepare for the subsequent infiltration step. The infiltration process was carried out in stages: first, 1:1 acetone and embedding agent mixture was used for 1 h, then 3:1 mixture was used for 3 h, and finally pure embedding agent was used for overnight infiltration. After the sample was completely infiltrated and embedded, it was placed in a 70°C oven for polymerization overnight. The embedded sample was sectioned on a LEICA EM UC7 ultramicrotome to obtain 70-90 nm ultrathin sections. The sections were double-stained with lead citrate and uranyl acetate (50% ethanol saturated solution) for 5-10 min each, and then observed under a transmission electron microscope to observe the ultrastructure of the tissue. The results are shown in Figure 9 It can be seen that the mitochondria in the control group showed a typical double-membrane structure, were evenly distributed and closely arranged, and had good membrane integrity. A large number of ferroptosis mitochondria appeared in the model group, and the mitochondrial cristae disappeared, broke and decreased, the mitochondrial volume decreased, the membrane density increased, and the nuclear membrane of the cell nucleus shrunk. In the FGMPPCL intervention group, the number of ferroptosis mitochondria was significantly reduced, the nuclear membrane of the cell nucleus returned to normal, and the mitochondria were evenly distributed, indicating that FGMPPCL has the ability to improve the morphology of ferroptosis.

[0018] Example 6, Active Peptide FGMPPCL Improves AKI: The experimental animals were grouped and treated as in Example 3, and then the mouse kidney tissues were quickly removed on ice, rinsed with pre-cooled normal saline, and stored in a -80°C refrigerator for standby use. The urea nitrogen and creatinine contents in the mouse kidney tissues were measured according to the requirements of the urea nitrogen (BUN) kit and creatinine (CRE) determination kit instructions (purchased from Nanjing Jiancheng Bioengineering Institute). Creatinine content determination: Hole classification: determination (T), standard (S), blank (B); Addition and corresponding sample amount: sample (only the determination hole adds 6 μL), reagent three: standard (only the standard hole adds 6 μL), double distilled water (only the blank hole adds 6 μL), reagent one: enzyme solution A (180 μL is added to the three holes), reagent two: enzyme solution B (60 μL is added to the three holes); Incubation and detection: 37°C incubation for 5 min, 546 nm wavelength measurement of absorbance A1; after adding reagent two, incubation under the same conditions to measure A2, and the formula ΔA = A2 - K*A1 is used for calculation.

[0019] The calculation formula for K is: ; The calculation formula for the creatinine content is: ; Among them, The meaning of the standard concentration is: 442 μmol / L; The determination hole (T) is the absorbance difference value calculated by the formula after sample addition, incubation, etc. The blank hole (B) is the absorbance difference value calculated by the formula after sample addition, incubation, etc. Urea nitrogen content determination: Blank tube: add 0.02 mL distilled water, 0.25 mL buffer enzyme solution; standard tube: add 0.02 mL 10 mmol / L BUN standard application liquid, 0.25 mL buffer enzyme solution; determination tube: add 0.02 mL sample to be tested, 0.25 mL buffer enzyme solution, mix the above sample-added blank tube, standard tube, and determination tube well, and place them in a 37°C environment, accurately water bath for 10 min, add 1 mL phenol color reagent and 1 mL alkaline sodium hypochlorite to the blank tube, standard tube, and determination tube, respectively, mix each tube well again, and place them in a 37°C environment, water bath for 10 min, and then measure the absorbance, wavelength 640 nm; ; In the formula, N is the dilution multiple of the sample before testing, and is 1 for no dilution. The results are as follows Figure 10 , 11As shown, the serum urea nitrogen (BUN) and creatinine (Scr) levels of the cisplatin-induced acute kidney injury model group mice were significantly increased, reaching 14.25 mmol / L and 50.71 μmol / L, respectively, while the corresponding levels of the control group mice were 10.15 mmol / L and 29.66 μmol / L, respectively. The results confirmed that cisplatin successfully induced an acute kidney injury model, accompanied by significant impairment of glomerular filtration function and metabolic waste excretion disorders. FGMPPCL intervention can significantly reduce the BUN and Scr levels of model mice (11.44 ± 0.53 mmol / L and 31.00 ± 1.46 μmol / L).

[0020] Example 7, Active Peptide FGMPPCL Improves Glomerulus, Renal Tubule, Interstitial Structure Morphology Analysis: The experimental animal grouping and treatment were the same as in Example 3. Subsequently, the mouse kidney tissue samples were quickly taken on ice, fixed at a ratio of 1:20 (tissue: fixative) for 48 h, and then sequentially dehydrated, paraffin-embedded, and embedded. 3 μm thick sections were prepared for subsequent histological staining. Mouse kidney tissue fixation: After the mice were sacrificed, the kidney tissue was quickly removed on ice to avoid excessive force causing the kidney to rupture. The excess blood was washed with normal saline, and immediately placed in 4% paraformaldehyde solution with a volume of 20 times the volume of the kidney tissue. The fixed kidney tissue samples were placed in the labeled embedding box, then placed in the pre-programmed dehydration machine for gradient treatment. The program settings are as follows: 3 h 4% paraformaldehyde → 1 h 75% alcohol → 1 h 85% alcohol → 1 h 95% alcohol → 1 h 95% alcohol → 1 h 100% alcohol → 45 min xylene → 1 h paraffin → 1 h paraffin → 2 h paraffin; The biological tissue embedding machine needs to be preheated to completely melt the paraffin. The sample after dehydration treatment is placed in the center of the mold, and the molten paraffin is slowly injected (note to avoid air bubbles). Immediately transfer to the -20°C freezing platform for rapid solidification. After the wax block is completely solidified, carefully remove the mold to obtain the shaped tissue wax block, which is stored at room temperature for future use. Set the rotary microtome to 3 μm thickness continuous sectioning. Hold the section edge with tweezers and float it on the surface of 37°C warm water. After the section naturally flattens, use a non-stick slide to retrieve it. Place it at a 45° angle to drain excess water. After melting the wax in a 60°C slide oven, store it at room temperature. The tissue sections were dewaxed in xylene and then rehydrated with a gradient ethanol solution. Next, the sections were stained in hematoxylin solution for 3-5 minutes. After differentiation with 1% hydrochloric acid alcohol and water back to blue, the cell nuclei appeared clear blue. After that, the cytoplasm was stained with eosin solution for 1-2 minutes to make it appear red. Finally, the sections were dehydrated, transparentized, and mounted with neutral gum to observe the staining of the cell nucleus and cytoplasm under a microscope. The result is as follows Figure 12 As shown in the figure, it can be seen that the glomeruli in the model group showed significant congestion and vacuolar degeneration, a large number of vacuoles appeared in the cytoplasm of renal tubular epithelial cells, the basement membrane was ruptured and accompanied by interstitial edema. After FGMPPCL intervention, the degree of glomerular vacuolation was significantly alleviated, the basement membrane structure was completely repaired, and the interstitial edema disappeared, indicating that FGMPPCL has the ability to improve the morphology of structures such as glomeruli, renal tubules, and interstitium.

[0021] Example 8: Active peptide FGMPPCL improves cisplatin-induced renal tubular injury: The paraffin sections prepared in Example 7 were dewaxed, treated with xylene, dehydrated with different concentrations of ethanol gradient, washed with distilled water several times, placed in EDTA antigen retrieval solution and microwave heated for antigen retrieval, cooled naturally, washed with PBS three times for 10 min, blocked with BSA for 30 min, and the blocking solution was discarded. The primary antibody was directly added and incubated at 4°C overnight, washed with PBS three times for 5 min each time, incubated with HRP secondary antibody at room temperature in the dark for 60 min, washed three times with PBS, added with Cy3 fluorescence enhancer, counterstained with DAPI for 5 min, washed with PBS several times, and mounted with anti-fluorescence quencher. Images were collected under a Nikon ECLIPSE Ti-SR microscope. The DAPI UV excitation wavelength was 330–380 nm, and the emission wavelength was 420 nm; the CY3 excitation wavelength was 510–560 nm, and the emission wavelength was 590 nm. The result is as follows Figures 13-15 As shown in Figure 2, the relative expression of KIM-1 in the model group was 1.26 ± 0.04, which was significantly higher than that in the control group (1.00 ± 0.11). P <0.05), after FGMPPCL intervention, KIM-1 expression level recovered to 0.98 ± 0.10 ( P <0.05); In addition, the relative expression of NGAL in the model group (5.43 ± 0.60) was significantly higher than that in the control group (1.00 ± 0.21), while FGMPPCL pretreatment significantly inhibited the upregulation of NGAL, reducing its expression to 3.61 ± 0.34 ( P <0.05), indicating that FGMPPCL could effectively reverse cisplatin-induced renal tubular injury.

[0022] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An active peptide for inhibiting ferroptosis, characterized in that, The amino acid sequence of the active peptide is shown as SEQ ID No.

1.

2. The active peptide of claim 1, wherein, The active peptide is derived from a walnut.

3. Use of the active peptide for inhibiting ferroptosis according to claim 1 or 2 in the preparation of a ferroptosis inhibitor.

4. Use of the active peptide for inhibiting ferroptosis according to claim 1 or 2 in the preparation of a drug for preventing or treating AKI.

5. Use according to claim 4, characterized in that, The AKI is caused by cisplatin.

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