Polypeptide compound and medical application thereof

Abstract

The invention discloses a polypeptide compound and medical application thereof. Experimental data shows that the polypeptide compound has a good inhibiting effect on IL-11, has a remarkable effect in a UUO-induced mouse renal fibrosis model, and can obviously inhibit protein and mRNA expression levels of fibrosis factors FN1 and alpha-SMA and mRNA expression of inflammatory factors TGF-beta and TNF-alpha and an injury marker Ngal.

Description

TECHNICAL FIELD

[0001] The present application relates to polypeptides, in particular to peptides or partially modified peptides having binding antagonist activity to the cytokine interleukin-11 (IL-11). BACKGROUND

[0002] Research has found that the cytokine interleukin-11 (IL-11) and its receptor IL-11Rα (interleukin-11 receptor subunit alpha) are potential targets for organ fibrosis and cancer, such as in kidney disease, lung cancer, liver cancer, non-alcoholic fatty liver disease, idiopathic pulmonary fibrosis, rheumatoid arthritis, and inflammatory bowel disease, etc. The expression is significantly up-regulated in various diseases, causing excessive deposition of extracellular matrix (ECM), ultimately leading to tissue damage, collagen accumulation and exacerbation of inflammatory response, accelerating the progression of related diseases. Therefore, inhibiting the activity of IL-11 and its downstream receptors can prevent the occurrence and development of related diseases such as fibrosis (such as pulmonary fibrosis, cardiac fibrosis, renal fibrosis, liver fibrosis), cancer (such as kidney cancer, liver cancer, lung cancer, breast cancer, uterine cancer) etc. The IL-11 antagonists found so far include neutralizing antibodies, polypeptides, siRNAs and recombinant proteins, but they are all in the early research stage, and have problems such as poor immunogenicity, stability, low activity and potential safety. SUMMARY

[0003] The first object of the present application is to provide an IL-11 polypeptide antagonist compound with high activity and good stability. The second object of the present application is to provide a pharmaceutical composition. The third object of the present application is to provide an application of the IL-11 polypeptide antagonist compound.

[0004] In order to achieve the above-mentioned first object, the technical scheme of the IL-11 polypeptide antagonist compound provided by the present application is as follows:

[0005] The present application provides a polypeptide compound selected from any one of the compounds shown in general formula (I)-(IV), a pharmaceutically acceptable salt, ester or amide thereof:

[0006] Ac-I-L-X 1a -X 2a -X 3a -X 4a -X 5a -X 6a -X 7a -D-X 8a -X 9a -X 10a -R-X 11a -L-L-L-X12a -K-T-R-L (I);

[0007] wherein X 1a is C or G, X 2a is C or G; X 3a is C or L; X 4a is H; X 5a is C or L; X 6a is C or T; X 7a is C or L; X 8a is W; X 9a is A or C; X 10a is V; X 11a is C or G; X 12a is C or L; X 1a -X 12a only two of the amino acid residues are C residues, and the side chains of the two C residues are bridged by -CH2-S-S-CH2-;

[0008] Ac-I-L-X 1b -X 2b -X 3b -X 4b -X 5b -X 6b -X 7b -D-X 8b -X 9b -X 10b -R-X 11b -L-L-L-X 12b -K-T-R-L (II);

[0009] wherein X 1b is G or X f , X 2b is G or X f ; X 3b is L or X f ; X 4b is H; X 5b is L or X f ; X 6b is T or X f ; X 7b is L or X f ; X 8b is W; X 9b is A; X 10b is V; X 11b is C, G or X f ; X 12b is C, L or X f ; X f is ; X 1b -X 12btwo or four of the amino acid residues are X f , if X 1b -X 12b two of the X f , then the side chains of the two X f are bridged by -CH2-CH2-CH2-CH2=CH2-CH2-CH2-CH2-; if X 1b -X 12b four of the X f , then the side chains of the two X f adjacent to each other are bridged by -CH2-CH2-CH2-CH2=CH2-CH2-CH2-CH2-; if X 1b -X 12b two of the amino acid residues are C residues, and the side chains of the two C residues are bridged by -CH2-S-S-CH2-;

[0010] Ac-I-L-X 1c -X 2c -X 3c -X 4c -X 5c -X 6c -X 7c -D-X 8c -X 9c -X 10c -R-X 11c -L-L-L-X 12c -K-T-R-L (III);

[0011] wherein X 1c is D, G, K or O, X 2c is D, E, G, K or O; X 3c is D, L or O; X 4c is A, H, R, S, V or Y; X 5c is D, K, L or O; X 6c is D, K, O or T; X 7c is D, K or L; X 8c is A, F or W; X 9c is A; X 10c is O or V; X 11c is D, G, K or O; X 12c is D, K, L or O; X 1b -X 12b the amino acid residues in X 1b -X 12b at least one of the amino acid residues in X 1b-X 12b The amino acid residues in X are at least one D and at least one O, with three amino acid residues separating D and O, and an intramolecular lactam bridge formed between the side chains of D and O residues; 1b -X 12b The amino acid residues in it are at least K and at least E, with three amino acid residues between K and E, and an intramolecular lactam bridge is formed between the side chains of K and E residues;

[0012] Ac-ILX 1d -X 2d -X 3d -X 4d -X 5d -X 6d -X 7d -DX 8d -X 9d -X 10d -RX 11d -LLLX 12d -KTRL(Ⅳ);

[0013] Among them, X 1d For G, X 2d For G; X 3d For L; X 4d H; X 5d For L; X 6d For T; X 7d For L; X 8d For W; X 9d For A; X 10d For V; X 11d For C; X 12d For C; the side chain of the 15th amino acid C residue, counting from the I-terminus connected to Ac, is bridged to the side chain of the 19th amino acid C residue by a bridge selected from any of the following:

[0014] , .

[0015] As a preferred option, in general formula (Ⅰ), X 1a -X 12athere are only two amino acid residues which are C residues, and the side chains of the two C residues are bridged by -CH2-S-S-CH2-; and the two bridged C residues are separated by 3 or 6 amino acids. For example, the 12th amino acid from the I end connected with Ac is a C residue, and the 19th amino acid is also a C residue, and the side chains of the two residues are bridged by -CH2-S-S-CH2-; the 4th amino acid from the I end connected with Ac is a C residue, and the 8th amino acid is also a C residue, and the side chains of the two residues are bridged by -CH2-S-S-CH2-.

[0016] As a preference, in the general formula (II), X 1b -X 12b there are two or four amino acid residues which are X f , if X 1b -X 12b there are two X f , the side chains of the two X f are bridged by -CH2-CH2-CH2-CH2=CH2-CH2-CH2-CH2-; and the two bridged X f are separated by 3 or 6 amino acids.

[0017] As a preference, in the general formula (II), X 1b -X 12b there are two or four amino acid residues which are X f , if X 1b -X 12b there are four X f , the side chains of the two X f adjacent to each other are bridged by -CH2-CH2-CH2-CH2=CH2-CH2-CH2-CH2-; and the two bridged X f are separated by 3 amino acids.

[0018] As a preference, in the general formula (II), if X 1b -X 12b there are two amino acid residues which are C residues, and the side chains of the two C residues are bridged by -CH2-S-S-CH2-; and the two bridged X f are separated by 3 amino acids.

[0019] As a preference, is , or .

[0020] As a preference, is .

[0021] As preferred, the polypeptide compound provided by the present application is selected from any one of the compounds shown in the following structural formula: .

[0022] The present application provides a polypeptide compound selected from the compound shown in general formula (V) or its pharmaceutically acceptable salt, ester or amide:

[0023]

[0024] wherein, W 11 is selected from any one of the following groups: 、 、 、 、 .

[0025] The present application provides a polypeptide compound selected from the compound shown in general formula (VI) or its pharmaceutically acceptable salt, ester or amide:

[0026]

[0027] wherein, X f is , H6 is R or V, D 10 is V or , L 19 is E, F, W or Y.

[0028] As preferred, the polypeptide compound provided by the present application is selected from any one of the compounds shown in the following structural formula:

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036] .

[0037] To achieve the above-mentioned second object, the technical scheme of the pharmaceutical composition provided by the present application is as follows:

[0038] The present application provides a pharmaceutical composition comprising the polypeptide compound and a pharmaceutically acceptable carrier. The pharmaceutical composition comprises a therapeutically effective amount of the above-mentioned peptide or pharmaceutically acceptable salt and a carrier and / or excipient.

[0039] To achieve the above-mentioned third object, the technical scheme of the IL-11 polypeptide antagonist compound provided by the present application is as follows:

[0040] The polypeptide compound provided by the present application can be applied in the preparation of an IL-11 antagonist.

[0041] The polypeptide compound provided by the present application can be applied in the preparation of a drug for treating or preventing fibrosis or cancer. The fibrosis is selected from lung fibrosis, heart fibrosis, kidney fibrosis, and liver fibrosis. The cancer is selected from kidney cancer, liver cancer, lung cancer, breast cancer, and uterine cancer. Specifically, the polypeptide compound provided by the present application can be applied in the preparation of a drug for preventing and / or treating an IL-11 mediated disease.

[0042] A person skilled in the art can prepare the polypeptide of the present application by combining known organic synthesis techniques and polypeptide synthesis techniques, and the starting materials are commercially available chemicals and / or amino acids described in chemical literature.

[0043] The term

[0044] Unless otherwise specified in the present application, the terms of the present application have the following meanings:

[0045] The term "pharmaceutically acceptable salt" refers to a salt of the bicyclic peptide of the present application which retains the biological effectiveness and properties of the free acid or the free base, and which is obtained by reacting the free acid with a non-toxic inorganic or organic base, or the free base with a non-toxic inorganic or organic acid.

[0046] The term "pharmaceutical composition" refers to a mixture of one or more of the peptides or stereoisomers, deuterated compounds, solvates, pharmaceutically acceptable salts or co-crystals or co-crystal of the present application, with other ingredients, wherein the other ingredients include physiologically / pharmaceutically acceptable carriers and / or excipients.

[0047] The term "carrier" refers to a system which does not cause significant irritation to the organism and does not eliminate the biological activity and properties of the administered bicyclic peptide, and can change the way the drug enters the human body and its distribution in the body, control the release rate of the drug and deliver the drug to the target organ, non-limiting examples include microcapsules and microspheres, nanoparticles, liposomes, etc.

[0048] A polypeptide refers to a compound formed by three or more amino acid molecules connected together by peptide bonds. The amino acid units in a polypeptide are called amino acid residues.

[0049] Unless otherwise specified, the number of amino acid residues of the polypeptide compounds of the present application is as follows:

[0050] .

[0051] Unless otherwise specified, all natural amino acid residues are represented by the following codes:

[0052]

[0053] Beneficial effects: Compared with the prior art, the present application has the following remarkable advantages: the compounds of the present application have a good inhibitory effect on IL-11 and have a significant effect in a UUO-induced mouse kidney fibrosis model, and can significantly inhibit the protein and mRNA expression levels of fibrosis factors FN1 and a-SMA, and the mRNA expression of inflammatory factors TGF-β and TNF-α and damage markers Ngal. BUN, creatinine and pathological sections also show that the compounds have obvious kidney protection and anti-fibrosis and inflammation effects. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 is the mass spectrum of compound 23-4p-31.

[0055] Figure 2 is the liquid chromatogram of compound 23-4p-31.

[0056] Figure 3 is the anti-fibrosis effect of 23-4p-31 on TGF-β1-induced HK-2 cells. Wherein A is the expression of FN1 and COL1A1 detected by western blot. B is the quantitative analysis of the expression levels of FN1 and COL1A1.

[0057] Figure 4 is the anti-kidney fibrosis effect of 23-4p-31 in a UUO prevention model. Wherein A is the expression of FN1 and a-SMA detected by western blot (dose of administration: PFD: 50 mg / kg, P12-L: 0.5 mg / kg, P12-H: 2.0 mg / kg). C is the mRNA expression of FN1 and Acta2. D is the mRNA expression of TNFα and IL-6. E is the mRNA expression of Kim1 and Ngal. F is the detection of the content of BUN in the plasma. G is the detection of the content of creatinine in the plasma. H is the Masson staining result of the kidney tissue of the mouse.

[0058] Figure 5 Binding mode of 23-4p-31 to IL-11Rα for MD simulation. DETAILED DESCRIPTION

[0059] The technical solutions of the present application are further described below in combination with examples.

[0060] Reagents and materials:

[0061] The chemical reagents used in the preparation of the compounds were sourced from Shanghai Bide Pharmaceutical Technology Co., Ltd., Shanghai Haohong Biological Pharmaceutical Technology Co., Ltd., and Sanen Chemical Technology Co., Ltd.

[0062] Instruments:

[0063] Low-resolution mass spectrometry was determined using a G6125B single quadrupole mass spectrometer.

[0064] Example 1: Synthesis of 23-4p-31

[0065]

[0066] Take 0.1 mmol Rink Amide Resin, add to the polypeptide synthesis tube, add 5 ml DCM, N2 bubble for 30 min, then filter off the filtrate. Add 5 ml DMF to the synthesis tube, N2 bubble for 1 min, then filter, repeat three times. Add 5 ml 20% Piperidine, N2 bubble for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2 bubble for 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, add to the synthesis tube, N2 bubble for 30 min. Wash the solid phase resin with DMF, N2 bubble for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2 bubble for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2 bubble for 1 min, repeat four times. Add 5 eq Fmoc-L-Arg(Pbf)-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, add to the synthesis tube, N2 bubble for 30 min, then filter off the filtrate, repeat twice. Wash the solid phase resin with DMF, N2 bubble for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2 bubble for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2 bubble for 1 min, repeat four times. Add 5 eq Fmoc-L-Thr(tBu)-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, add to the synthesis tube, N2 bubble for 30 min, then filter off the filtrate, repeat twice. Wash the solid phase resin with DMF, N2 bubble for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2 bubble for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2 bubble for 1 min, repeat four times. Add 5 eq Fmoc-L-Lys(Boc)-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, add to the synthesis tube, N2 bubble for 30 min. Wash the solid phase resin with DMF, N2 bubble for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2 bubble for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2 bubble for 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, add to the synthesis tube, N2 bubble for 30 min. Wash the solid phase resin with DMF, N2 bubble for 1 min, repeat three times.Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat four times. Add 5 eq Fmoc-Gly-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling for 60 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat four times. Add 5 eq Fmoc-L-Arg(Pbf)-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat four times. Add 5 eq Fmoc-L-Val-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat three times.Add 5 ml 20% Piperidine, N2bubbling 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling 1 min, repeat four times. Add 5 eq Fmoc-L-Ala-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling 30 min. Wash the solid phase resin with DMF, N2bubbling 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling 1 min, repeat four times. Add 5 eq FMOC-L-Trp(Boc)-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling 30 min. Wash the solid phase resin with DMF, N2bubbling 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling 1 min, repeat four times. Add 5 eq FMOC-L-Aspartic acid beta-tert-butyl ester, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling 60 min. Wash the solid phase resin with DMF, N2bubbling 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling 30 min. Wash the solid phase resin with DMF, N2bubbling 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling 1 min, repeat four times. Add 5 eq FMOC-ORN(ALOC)-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling 30 min. Wash the solid phase resin with DMF, N2bubbling 1 min, repeat three times. Add 5 ml 20% Piperidine, N2bubbling 5 min, then filter off the filtrate. Repeat twice, then wash the solid phase resin with DMF, N2bubbling 1 min, repeat four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA, DMF as solvent, into the synthesis tube, N2bubbling 30 min.Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then remove the filtrate by suction filtration. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for four times. Add 5 eq Fmoc-L-His(Trt)-OH, 5 eq HATU, 10 eq DIPEA in DMF to the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then remove the filtrate by suction filtration. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA in DMF to the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then remove the filtrate by suction filtration. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for four times. Add 5 eq FMOC-L-Asp(OAll)-OH, 5 eq HATU, 10 eq DIPEA in DMF to the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then remove the filtrate by suction filtration. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for four times. Add 5 eq FMOC-L-Gly-OH, 5 eq HATU, 10 eq DIPEA in DMF to the synthesis tube, N2bubbling for 60 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then remove the filtrate by suction filtration. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for four times. Add 5 eq Fmoc-L-Leu-OH, 5 eq HATU, 10 eq DIPEA in DMF to the synthesis tube, N2bubbling for 30 min. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for three times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then remove the filtrate by suction filtration. Repeat twice, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for four times. Add 5 eq FMOC-L-Ile-OH, 5 eq HATU, 10 eq DIPEA in DMF to the synthesis tube, N2bubbling for 30 min.Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for 3 times. Add 5 ml 20% Piperidine, N2bubbling for 5 min, then filter off the filtrate. Repeat for 2 times, then wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for 4 times. Add 5 eq Acetic anhydride, 10 eq DIPEA, DCM as solvent, add into the synthesis tube, N2bubbling for 60 min, repeat for 2 times. Wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for 3 times. Add DCM to wash, N2bubbling for 1 min, then filter off, repeat for 4 times. Add 15 eq Phenylsilane, N2bubbling for 5 min, add 0.25 eq Pd(PPh3)4, N2bubbling for 40 min, add DCM to wash, N2bubbling for 1 min, then filter off, repeat for 4 times, wash the solid phase resin with DMF, add 5 eq PYBOP, 5 eq HOBT, 10 eq DIPEA, DMF as solvent, add into the synthesis tube, N2bubbling for 4 h, wash the solid phase resin with DMF, N2bubbling for 1 min, repeat for 3 times. Add DCM to wash, N2bubbling for 1 min, then filter off, repeat for 4 times. Pour out and dry. Get the solid phase product, pour the solid phase product into 25 ml tomato bottle, add 5 ml 95% TFA (TFA:Tips:H2O = 95%:2.5%:2.5%), stir for 2 h at room temperature, then filter off, pour the filtrate into cold ether, centrifugal at 4000 r / min for 5 min, discard the supernatant and keep the precipitate. Add cold ether, shake the precipitate evenly, centrifugal at 4000 r / min for 5 min, discard the supernatant and keep the precipitate. Repeat for 2 times. Vacuum filter off the precipitate, make it into solid powder. Dissolve the solid with methanol, filter through a microporous filter, purify by HPLC to get the product, after mass spectrometry analysis, freeze-drying to get the product 23-4p-31.

[0067] Refer to the method of Example 1, according to the different substitution of amino acid residues, the corresponding raw materials are prepared to prepare the compounds of Examples 2-55. And confirmed by mass spectrometry analysis.

[0068] Table 1 Structure and mass spectrometry data of compounds of Examples 1-55

[0069]

[0070] The compounds of Examples 43-47 are modified based on compound 23-4P-31. The compounds of Examples 48-55 are modified based on compound 23-4P-3. Specifically, Ac is not counted, counting from I connected to Ac, and the 6th H, 19th L and 10th D of 23-4P-3 are mutated as the mother nucleus:

[0071] Table 2 Mutation groups of compounds of Examples 48-55

[0072]

[0073] Biological test

[0074] I. Inhibition of IL-11 by the compounds (IC 50 ) detection

[0075] 1. Experimental method

[0076] Based on STATs signaling pathway, a luciferase reporter gene cell line (IL-11R 293 cell line) was constructed for in vitro activity detection of IL-11 polypeptide compounds. The cells were placed in high glucose medium (hDMEM) containing 10% FBS, 1% P / S, 400 μg / ml G418, 125 μg / ml Hygromycin and 4 μg / ml Blasticidin, and cultured at 37°C, 5% CO2 saturated water environment. For activity detection, in 96-well plates, cells were plated at 1.5*10 4 cells / well, and after overnight culture, different concentrations of polypeptide compounds were given (the maximum concentration was set to 1 mM, and 10-fold dilution method was used for dilution), and after drug administration, the cells were incubated in the incubator for 1 h, 1.0 nM of IL-11 was added to each well, and after 6 h of continuous culture, luciferase detection kit was used for luminescence detection, and Graphpad prism9.5 data processing was used to calculate IC 50 .

[0077] 2. Experimental results

[0078] Table 3 Inhibitory effect of compounds detected at the cellular level

[0079]

[0080] II. Anti-renal fibrosis effect of 23-4P-31 at the cellular level:

[0081] 1. Experimental method

[0082] A model was established using TGF-β1 to induce renal proximal tubular epithelial cells (HK-2). The modeling method is as follows: HK-2 cells were cultured in DMEM low sugar (1 g / L glucose) medium containing 10% FBS and 1% P / S, and 2.5 x 10 5 cells / well were inoculated in a 6-well plate and cultured overnight, and the next day different concentrations of compounds (2 μM, 5 μM, 8 μM) or positive drug pirfenidone (PFD, 0.5 mM) were administered, and TGF-β1 (5 ng / ml) induction was performed at the same time. After 48 hours, the cells were collected, total protein was extracted after RIPA lysis, and the expression of corresponding fibrosis proteins FN1 and Collagen I was detected by WB.

[0083] 2. Experimental results

[0084] As shown in Figure 3 , the 23-4P-31 compound can significantly reduce the expression of FN1 and Collage I on HK2 cells induced by TGF-β1, indicating that the compound can significantly antagonize fibrosis.

[0085] Evaluation of the anti-fibrosis effect of 23-4P-31 in a UUO-induced mouse model

[0086] A UUO model was established by making a left abdominal incision and double-ligating the left ureter with 3-0 silk. The UUO mice were divided into three groups, and 0.5 mg / kg or 2 mg / kg of 23-4P-31 compound or 50 mg / kg of positive drug PFD was injected subcutaneously on the first day of modeling, and the injection was continued for 6 days. The sham operation group and the solvent group were injected with the same volume of normal saline, and the serum was taken on the 7th day. The mice were euthanized, and the kidney tissue was taken for subsequent data analysis.

[0087] As shown in Figure 4 , the 23-4P-31 compound has a significant effect in the UUO-induced mouse renal fibrosis model, and can significantly inhibit the protein and mRNA expression levels of fibrosis factors FN1 and α-SMA, as well as the mRNA expression of inflammatory factors TGF-β and TNF-α and the damage marker Ngal (C) in Figure 4 In addition, BUN, creatinine, and pathological sections also show that the compound has a significant kidney protection and anti-fibrosis inflammation effect.

[0088] III. Binding mode of 23-4P-31 to IL-11Rα:

[0089] Microsecond-scale atomic-scale molecular dynamics simulations were employed to investigate the potential interaction between the cyclic peptide 23-4p-31 and the extracellular domain of IL-11Rα (IL-11Rαec). The lactam was parameterized using the CHARMM universal force field (CGenFF), and the initial coordinates of 23-4p-31 were constructed using Coot. The initial coordinates of hIL-11Rα were constructed using PDB 8QY4 and PDB 8DPU models. The simulation system was prepared using the multi-component assembler module in CHARMMGUI, and the simulation box was solvated using CHARMM TIP3P water molecules. hIL-11Rα was placed at the center of the box, and 23-4p-31 was placed in the same position as the complex. All charged residues maintained their predominantly protonated state at neutral pH (7.0). The simulation environment was 150 mM NaCl to ensure charge neutralization. MD simulations were run using GROMACS (version 2024), with the CHARMM 36m force field applied to IL-11Rα.

[0090] like Figure 5 As shown, 23-4p-31 remained bound to its original position, but the binding mechanism differed from the complex structure. The lactam ring of 23-4p-31 formed a hydrogen bond interaction with the W188 of the acceptor, and the lactam ring was also stabilized. 1 IGL 3 The geometry of the structure was found to have a brief binding with the RRS finger on IL-11Rα during simulation.

Claims

1. A polypeptide compound, characterized in that, It is selected from any compound shown in formulas (I)-(IV), and its pharmaceutically acceptable salt, ester, or amide: Ac-I-L-X 1a -X 2a -X 3a -X 4a -X 5a -X 6a -X 7a -D-X 8a -X 9a -X 10a -R-X 11a -L-L-L-X 12a -K-T-R-L(Ⅰ); Among them, X 1a For C or G, X 2a For C or G; X 3a For C or L; X 4a H; X 5a For C or L; X 6a For C or T; X 7a For C or L; X 8a For W; X 9a It is A or C; X 10a For V; X 11a For C or G; X 12a For C or L; X 1a -X 12a It contains exactly two amino acid residues that are C residues, and the side chains of the two C residues are bridged by -CH2-SS-CH2-. Ac-I-L-X 1b -X 2b -X 3b -X 4b -X 5b -X 6b -X 7b -D-X 8b -X 9b -X 10b -R-X 11b -L-L-L-X 12b -K-T-R-L(Ⅱ); Among them, X 1b For G or X f X 2b For G or X f ;X 3b For L or X f ;X 4b H; X 5b For L or X f ;X 6b For T or X f ;X 7b For L or X f ;X 8b For W; X 9b For A; X 10b For V; X 11b For C, G or X f ;X 12b For C, L or X f ;X f for ;X 1b -X 12b It contains two or four amino acid residues of type X. f If X 1b -X 12b There are two X's f Then X f The side chains are bridged by -CH2-CH2-CH2-CH2=CH2-CH2-CH2-CH2-; if X 1b -X 12b There are four X's f Then the two nearest X f The side chains are bridged by -CH2-CH2-CH2-CH2=CH2-CH2-CH2-CH2-; if X 1b -X 12b It contains two amino acid residues that are C residues, and the side chains of the two C residues are bridged by -CH2-SS-CH2-. Ac-I-L-X 1c -X 2c -X 3c -X 4c -X 5c -X 6c -X 7c -D-X 8c -X 9c -X 10c -R-X 11c -L-L-L-X 12c -K-T-R-L(Ⅲ); Among them, X 1c For D, G, K, or O, X 2c For D, E, G, K, or O; X 3c For D, L, or O; X 4c For A, H, R, S, V, or Y; X 5c For D, K, L, or O; X 6c For D, K, O, or T; X 7c For D, K, or L; X 8c For A, F, or W; X 9c For A; X 10c For O or V; X 11c For D, G, K, or O; X 12c For D, K, L, or O; X 1b -X 12b The amino acid residues in X must satisfy at least one of the following conditions: 1b -X 12b The amino acid residues in X are at least one D and at least one K, separated by three amino acid residues, and an intramolecular lactam bridge is formed between the side chains of the D and K residues; 1b -X 12b The amino acid residues in X are at least one D and at least one O, with three amino acid residues separating D and O, and an intramolecular lactam bridge formed between the side chains of D and O residues; 1b -X 12b The amino acid residues in it are at least K and at least E, with three amino acid residues between K and E, and an intramolecular lactam bridge is formed between the side chains of K and E residues; Ac-I-L-X 1d -X 2d -X 3d -X 4d -X 5d -X 6d -X 7d -D-X 8d -X 9d -X 10d -R-X 11d -L-L-L-X 12d -K-T-R-L(Ⅳ); Among them, X 1d For G, X 2d For G; X 3d For L; X 4d H; X 5d For L; X 6d For T; X 7d For L; X 8d For W; X 9d For A; X 10d For V; X 11d For C; X 12d For C; the side chain of the 15th amino acid C residue, counting from the I-terminus connected to Ac, is bridged to the side chain of the 19th amino acid C residue by a bridge selected from any of the following: 、 。 2. The polypeptide compound according to claim 1, characterized in that, for , or .

3. The polypeptide compound according to claim 1, characterized in that, for .

4. The polypeptide compound according to claim 1, characterized in that, It is selected from any one of the compounds shown in the following structural formulas: 。 5. The polypeptide compound according to claim 1, characterized in that, It is selected from compounds of general formula (V) or their pharmaceutically acceptable salts, esters or amides: Among them, W 11 Selected from any of the following groups: , , , , .

6. The polypeptide compound according to claim 1, characterized in that, It is selected from compounds of general formula (VI) or their pharmaceutically acceptable salts, esters or amides: Among them, X f for H6 is R or V, D 10 For V or L 19 It can be E, F, W, or Y.

7. The polypeptide compound according to claim 6, characterized in that, It is selected from any one of the compounds shown in the following structural formulas: 。 8. A pharmaceutical composition comprising the polypeptide compound of any one of claims 1-7 and a pharmaceutically acceptable carrier.

9. The use of any one of the polypeptide compounds according to claims 1-7 in the preparation of IL-11 antagonists.

10. The use of any of the polypeptide compounds according to claims 1-7 in the preparation of medicaments for treating or preventing fibrosis or cancer.

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