阅读说明：本技术 多肽rly4及其促进肝再生和抑制肝细胞凋亡的用途 (Polypeptide RLY4 and application thereof in promoting liver regeneration and inhibiting hepatocyte apoptosis ) 是由 张时群 卢肖宇 王�华 李天然 于 2019-10-23 设计创作，主要内容包括：本发明公开了一种多肽及其促进肝细胞增殖和/或抑制肝细胞凋亡的用途。本发明的能促进肝细胞增殖和/或抑制肝细胞凋亡的多肽,其氨基酸序列与SEQ ID NO:1所示的氨基酸序列相比,具有3/4以上的序列一致性,多肽长度为4个氨基酸,具有分子量小、易于合成、免疫原性低等优点,因此本发明的多肽在肝病治疗中具有广阔的应用前景。(The invention discloses a polypeptide and application thereof in promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis. Compared with the amino acid sequence shown in SEQ ID NO. 1, the amino acid sequence of the polypeptide capable of promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis has the sequence consistency of more than 3/4, the length of the polypeptide is 4 amino acids, and the polypeptide has the advantages of small molecular weight, easy synthesis, low immunogenicity and the like, so the polypeptide has wide application prospect in treatment of liver diseases.)

1. A polypeptide capable of promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis has amino acid sequence identity of 3/4 or more compared with the amino acid sequence shown in SEQ ID NO. 1.

2. The polypeptide of claim 1, wherein the amino acid sequence is set forth in SEQ ID NO 1.

3. The polypeptide of claim 1 or 2, which has a terminal modification, which is an N-terminal acetylation modification or/and a C-terminal amidation modification.

4. Use of the polypeptide of claim 1 or a salt thereof for the manufacture of a medicament for promoting hepatocyte proliferation or treating a disease caused by hepatocyte apoptosis.

5. The use of claim 4, wherein the salt is an acetate, hydrochloride or phosphate salt of the polypeptide.

6. The use of claim 4, wherein the disease caused by apoptosis of liver cells is liver failure, viral hepatitis, liver fibrosis, liver cirrhosis, alcoholic liver disease, non-alcoholic fatty liver disease or autoimmune liver disease.

7. The use of claim 4, wherein the promotion of hepatocyte proliferation is the promotion of liver regeneration in vivo or the promotion of hepatocyte growth in vitro.

8. A medicament for promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis, which comprises the polypeptide or a salt thereof according to claim 1.

9. The medicament of claim 8, wherein the disease caused by apoptosis of liver cells is acute liver failure.

10. The medicament of claim 8, wherein the promotion of hepatocyte proliferation is the promotion of liver regeneration in vivo or the promotion of hepatocyte growth in vitro.

Technical Field

The invention relates to the technical field of cell proliferation and apoptosis, in particular to a polypeptide RLY4 and application thereof in promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis.

Background

The liver is the largest internal organ in the human body (about 2.5% of the total mass of the human body), and is also the central metabolic organ. The major contributors to liver function are parenchymal cells, which account for 80% of the total liver cells. The liver cells play a series of roles including plasma production, carrier protein synthesis, detoxification of digests, conjugation and hormone secretion, regulation of synthesis and metabolism of blood lipids and amino acids, and the like.

Apoptosis (apoptosis) is an active suicide process of cells in specific environments. Apoptosis was two different patterns of apoptosis and death observed by Kerr et al in 1972 when studying liver ischemia. The cell apoptosis is characterized by cell shrinkage, cellular bulge of cell membrane, formation of apoptotic bodies, degradation of nuclear fragments and nuclear DNA and other abnormal phenomena. Apoptosis is a major feature of pathological changes of many diseases in clinic, and particularly in liver diseases, apoptosis of liver cells is an important factor causing liver damage. Hepatocyte apoptosis plays an important role in the mechanism of liver pathology, and disruption of death receptor pathways is considered to be one of the important causes for triggering the development of acute/chronic liver injury. In recent years, researches show that the apoptosis of liver cells is widely involved in pathological processes of various liver diseases, including liver failure, viral hepatitis, hepatic fibrosis, liver cirrhosis, alcoholic liver diseases, non-alcoholic fatty liver diseases, autoimmune liver diseases and the like.

Liver Failure (LF) is a serious liver damage caused by various factors such as virus, drug, alcohol, etc., causing serious dysfunction or decompensation of detoxification, excretion, synthesis, etc., and a group of clinical symptoms mainly manifested by blood coagulation dysfunction, severe jaundice, ascites, hepatic encephalopathy, even gastrointestinal hemorrhage, etc., with extremely high mortality rate, which is one of the clinically common critical conditions in the department of hepatopathy. According to the difference of pathological features and disease processes, 2012 edition of guidelines for liver failure diagnosis and treatment classifies liver failure into Acute Liver Failure (ALF), subacute liver failure (SALF), chronic-on-chronic liver failure (ACLF) and Chronic Liver Failure (CLF). Liver failure is clinically critical and still lacks specific drugs with definite curative effects so far, so that the liver failure becomes one of the worldwide intractable diseases, and although artificial liver and liver transplantation are effective treatment methods, the treatment methods cannot be widely popularized and used in China due to the expensive cost, shortage of liver sources, rejection and the like. There is an urgent need for new drugs and methods for treating the above-mentioned liver diseases.

RLY4 is a polypeptide containing 4 amino acids (RLYE), and it has been reported that RLY4 can inhibit angiogenesis induced by Vascular Epidermal Growth Factor (VEGF), and can be used for treating diseases such as tumor and wet macular degeneration (see chinese patent CN108350029A, and non-patent documents 1, 2, and 3), but there is no report that RLY4 is used for promoting hepatocyte regeneration and inhibiting hepatocyte apoptosis.

Non-patent document 1: baek YY, et al, the tetrapeptide Arg-Leu-Tyr-Glu inhibitors VEGF-induced angiogenesis. biochem Biophys Res Commun.2015Aug7; 463(4) 532-7;

non-patent document 2: baek YY, et al, Arg-Leu-Tyr-Glu tetrapeptide inhibition of tumor promotion by suppression of tumor formation and vascular permeability via VEGFreceptor-2 antagnonism, oncotarget.2017Feb 14; 11763-;

non-patent document 3: park W, et al Arg-Leu-Tyr-Glu repressives recovery endogenous metabolism and Choroidal neovenous inactivation by Inhibiting the VEGF Receptor 2 signalling pathway biomol ther (Seoul).

Disclosure of Invention

Based on the above problems, the present invention aims to overcome the defects of the prior art and provide a polypeptide capable of promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following aspects:

the present invention provides a polypeptide, the amino acid sequence of which has a sequence identity of more than 3/4 compared to the amino acid sequence shown in SEQ ID NO. 1. It should be noted that, compared with the amino acid sequence shown in SEQ ID NO. 1, the sequence identity of the claimed polypeptide sequence may be 3/4 or 4/4, but is not limited to 3/4 or more, and may also be 1/2, so long as the corresponding polypeptide has the effect of promoting hepatocyte proliferation or inhibiting hepatocyte apoptosis, which falls within the protection scope of the present invention.

Furthermore, the amino acid sequence of the polypeptide is shown as SEQ ID NO. 1.

Further, the polypeptide has terminal modification, and the terminal modification is N-terminal acetylation modification or/and C-terminal amidation modification.

In another aspect, the present invention provides the use of the above-mentioned polypeptide or a salt thereof for the preparation of a medicament for promoting hepatocyte proliferation or treating a disease caused by hepatocyte apoptosis.

Further, the salt is acetate, hydrochloride or phosphate of the polypeptide.

Further, the disease caused by the apoptosis of liver cells is liver failure, viral hepatitis, liver fibrosis, liver cirrhosis, alcoholic liver disease, non-alcoholic fatty liver disease or autoimmune liver disease. More preferably acute liver failure.

Further, the promotion of hepatocyte proliferation is the promotion of liver regeneration in vivo or the promotion of hepatocyte growth in vitro.

In still another aspect, the present invention provides a medicament for promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis, which comprises the above-mentioned polypeptide or a salt thereof. Further, the salt is acetate, hydrochloride or phosphate of the polypeptide.

Further, the disease caused by hepatocyte apoptosis is acute liver failure.

Further, the promotion of hepatocyte proliferation is the promotion of liver regeneration in vivo or the promotion of hepatocyte growth in vitro.

Further, the medicament is in a liquid dosage form or a freeze-dried powder. Still further, the medicament further comprises a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier can be routinely selected by those skilled in the art according to the dosage form of the drug and the like. When the drug is in a liquid dosage form, administration can be by intravenous or subcutaneous injection.

In conclusion, the beneficial effects of the invention are as follows:

the invention provides a polypeptide RLY4 capable of promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis, which is 4 amino acids in length and has the advantages of small molecular weight, easy synthesis, low immunogenicity and the like, so the polypeptide has wide application prospect in liver disease treatment.

Drawings

FIG. 1 is an HPLC chromatogram of polypeptide RLY4 of the present invention;

FIG. 2 is a graph showing the results of the activity assay of the polypeptide RLY4 of the present invention in promoting hepatocyte proliferation;

FIG. 3 is a diagram showing the results of the activity test of the polypeptide RLY4 of the present invention for inhibiting hepatocyte apoptosis.

Detailed Description

The inventor of the application conducts experimental screening on a large number of polypeptides in the prior art, and unexpectedly finds that the polypeptide RLY4 not only can promote the proliferation of liver cells, but also can inhibit the apoptosis of the liver cells.

In some embodiments, the present invention provides a polypeptide, RLY 4/a salt thereof, capable of promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis and uses thereof. Furthermore, the amino acid sequence of the polypeptide RLY4 for promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis is shown as SEQ ID NO. 1.

In some embodiments, the salt comprises an acetate, hydrochloride, or phosphate salt of the polypeptide.

In some embodiments, the polypeptide is terminally modified. Further, the terminal modification is an N-terminal acetylation modification or a C-terminal amidation modification.

In some embodiments, the present invention also provides the use of the above-described polypeptide or a salt thereof for the preparation of a medicament for promoting hepatocyte proliferation or treating a disease caused by hepatocyte apoptosis. Further, the medicament is in a liquid dosage form or a freeze-dried powder. Further, the disease caused by the apoptosis of liver cells is liver failure, viral hepatitis, liver fibrosis, liver cirrhosis, alcoholic liver disease, non-alcoholic fatty liver disease or autoimmune liver disease. More preferably, the liver failure is acute liver failure.

In some embodiments, the promoting hepatocyte proliferation is promoting liver regeneration in vivo or promoting hepatocyte growth in vitro.

The invention also provides a medicament for promoting hepatocyte proliferation and/or inhibiting hepatocyte apoptosis, which comprises the polypeptide or a salt thereof.

Preferably, the medicament is in a liquid dosage form or a lyophilized powder.

Preferably, the promotion of hepatocyte proliferation is promotion of liver regeneration in vivo or promotion of hepatocyte growth in vitro.

Preferably, the medicament further comprises a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier can be routinely selected by those skilled in the art according to the dosage form of the drug and the like.

When the drug is in a liquid dosage form, administration can be by intravenous or subcutaneous injection.

The inventor of the application proves that the polypeptide RLY4 shown in SEQ ID NO. 1 has the activities of promoting the proliferation of the liver cells and inhibiting the apoptosis of the liver cells through in vitro cell experiments, so that the polypeptide can be used for promoting the proliferation of the liver cells or treating diseases caused by the apoptosis of the liver cells. Research shows that the diseases of hepatocyte apoptosis include liver failure, viral hepatitis, cholestatic liver injury, alcoholic liver injury, non-alcoholic steatohepatitis, cirrhosis, toxin-or drug-mediated liver injury and the like, and the polypeptide of the present invention has the activity of inhibiting hepatocyte apoptosis, so the polypeptide can be used for treating the diseases.

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to the accompanying drawings and specific embodiments. The reagents or methods used in the present invention are those conventional in the art unless otherwise specified.