CN113616777A

CN113616777A - Transformation applications for improving endoplasmic reticulum stress based on major urinary proteins

Info

Publication number: CN113616777A
Application number: CN202110952045.9A
Authority: CN
Inventors: 石国军; 陈燕铭; 何学敏; 高荣; 王何婷
Original assignee: Third Affiliated Hospital Sun Yat Sen University
Current assignee: Third Affiliated Hospital Sun Yat Sen University
Priority date: 2021-08-18
Filing date: 2021-08-18
Publication date: 2021-11-09

Abstract

The invention relates to the technical field of biology, and particularly discloses application of main urinary protein in preparation of a medicine for improving endoplasmic reticulum stress. Experiments prove that the urinary MUPs and MUP1 can obviously improve endoplasmic reticulum stress of mouse liver cells and human liver cells. Also, urine MUPs and MUP1 can improve insulin resistance caused by endoplasmic reticulum stress in the liver.

Description

Transformation applications for improving endoplasmic reticulum stress based on major urinary proteins

Technical Field

The invention relates to the technical field of biology, in particular to application of main urinary protein in preparing a medicine for improving endoplasmic reticulum stress and insulin resistance caused by the endoplasmic reticulum stress.

Background

Metabolic diseases, while presenting a wide variety of clinical manifestations and signs, share many common pathophysiological bases. The liver is one of the most important metabolic organs, and is mainly involved in protein synthesis, glycolipid metabolism, and the like.

Endoplasmic reticulum stress refers to the phenomenon that when cells are stimulated by internal and external factors, the balance state of the endoplasmic reticulum shape and functions is damaged, then molecular biochemical changes occur, protein processing and transportation are blocked, a large amount of unfolded or misfolded proteins are accumulated in the endoplasmic reticulum, and the cells can take corresponding response measures to relieve the recovery of the normal functions of the endoplasmic reticulum. Wherein the endoplasmic reticulum stress of the liver plays an important role in the occurrence and the development of metabolic diseases. Abnormal stress of liver endoplasmic reticulum is closely related to insulin resistance, glycolipid metabolic disorder and chronic inflammatory reaction, and is a common pathogenesis of metabolic diseases such as obesity, diabetes, hyperlipidemia, non-alcoholic fatty liver and the like.

Hepatic insulin resistance is the core of systemic metabolic disorders, and improving hepatic endoplasmic reticulum stress can improve insulin sensitivity. At present, the treatment of diseases such as obesity, non-alcoholic fatty liver and the like still mainly depends on life style intervention, effective clinical medicines are lacked, and the improvement of endoplasmic reticulum stress of the liver becomes a potential target for improving metabolic abnormality.

MUP (major urinary protein), also known as the major urinary protein, belongs to the lipocalin family, is synthesized primarily by the liver, secreted into the blood, and excreted by the kidney. The mouse MUP gene consists of 21 functional genes and 21 pseudogenes. MUP has a barrel-shaped structure formed by 8 beta chains and is lipophilic. MUP is used as a carrier to be combined with lipophilic micromolecules such as pheromone and the like, so that the half-life period of the MUP is prolonged, the MUP becomes a symbol of individual identity of animals through urine discharge, and participates in social behaviors such as puppet, territorial consciousness, fighting and the like of the animals. The research shows that MUP1 is regulated by the nutritional state, can also regulate the metabolism of glycolipid in the liver and improve the function of muscle mitochondria, thereby participating in the regulation of metabolism.

However, the relationship between major urinary proteins and hepatic endoplasmic reticulum stress is not currently reported.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide the application of the main urine protein in preparing the medicine for improving endoplasmic reticulum stress.

In a first aspect, the present invention provides the use of major urinary proteins as inhibitors of endoplasmic reticulum stress.

As a preferred embodiment of the use according to the invention, the major urinary proteins comprise major urinary protein 1 or urinary MUPs.

Experiments prove that the main urine protein 1 and urine MUPs can inhibit endoplasmic reticulum stress of mouse liver cells and human liver cells.

As a preferred embodiment of the use according to the invention, the endoplasmic reticulum stress comprises hepatic endoplasmic reticulum stress.

In a second aspect, the present invention provides the use of a major urinary protein for the manufacture of a medicament for ameliorating endoplasmic reticulum stress. More preferably, the present invention provides the use of major urinary protein 1 and/or urinary MUPs in the manufacture of a medicament for ameliorating endoplasmic reticulum stress.

As a preferred embodiment of the use according to the invention, ERS inducers thapsigargin or tunicamycin are used to induce endoplasmic reticulum stress.

More preferably, the ERS inducer thapsigargin concentration is 200 nM; the tunicamycin concentration is 2.5-5.0 ug/ml.

In a third aspect, the invention provides the use of a principal urinary protein in the manufacture of a medicament for the treatment of a condition caused by endoplasmic reticulum stress in the liver. More preferably, the invention provides the use of major urinary protein 1 and/or urinary MUPs in the manufacture of a medicament for the treatment of diseases caused by stress of the endoplasmic reticulum of the liver.

As a preferred embodiment of the use according to the invention, the disease comprises hepatic insulin resistance or diabetes.

In a fourth aspect, the present invention provides a medicament for improving endoplasmic reticulum stress, the active ingredient of which comprises major urinary protein 1 and/or urinary MUPs.

As a preferred embodiment of the medicament of the present invention, the medicament comprises a pharmaceutically acceptable carrier.

More preferably, the carrier is solvent PBS.

The key marker of the insulin signal pathway is p-AKT, and the increase of the p-AKT level indicates the enhancement of insulin sensitivity. According to experiments, the level of p-AKT is increased by adding the recombinant MUP1, which indicates that the insulin sensitivity is enhanced, and the result shows that the recombinant MUP1 improves the insulin resistance caused by endoplasmic reticulum stress of HepG2 cells.

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

the urinary MUPs and MUP1 can obviously improve endoplasmic reticulum stress of mouse liver cells and human liver cells. Also, urine MUPs and MUP1 can improve insulin resistance caused by endoplasmic reticulum stress in the liver.

Drawings

FIG. 1 is a graph showing the expression level of a key gene of the endoplasmic reticulum stress pathway of mouse liver primary cells according to the present invention (RNA-seq);

FIG. 2 is a schematic diagram of a cell processing method in step two of example 1;

FIG. 3 is a graph of the results of urine MUPs inhibiting endoplasmic reticulum stress in HepG2 cells;

FIG. 4 is a graph showing the results of urine MUPs inhibiting endoplasmic reticulum stress in AML12 cells;

FIG. 5 is a schematic diagram of a method of treating cells in step four of example 1;

FIG. 6 is a graph showing the results of recombinant MUP1 inhibiting endoplasmic reticulum stress in HepG2 cells;

FIG. 7 is a graph showing the results of insulin resistance in HepG2 cells induced by endoplasmic reticulum stress;

FIG. 8 is a schematic diagram of a method of treating cells in step six of example 1;

FIG. 9 is a graph showing the results of recombinant MUP1 in ameliorating insulin resistance induced by endoplasmic reticulum stress in HepG2 cells;

FIG. 10 is a schematic diagram of a method of treating cells in step seven of example 1;

FIG. 11 is a graph showing the results of urine MUPs ameliorating insulin resistance induced by endoplasmic reticulum stress in HepG2 cells.

Detailed Description

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.

In the following experiments, Tg is ERS inducer thapsigargin and Tm is tunicamycin.

Buffer 1: 115mM NaC1, 5mM KCl, 1mM KH₂PO₄0.5mM EGTA and 25mM sodium HEPES buffer, pH 7.4.

Buffer 2: 115mM NaC1, 5mM KCl, 1mM KH₂PO4，1mM CaCl₂And 25mM sodium HEPES buffer, pH 7.4.

Collagenase: collagenase D0.5 mg/ml + collagenase P0.05 mg/ml.

Example 1 experiment of improvement of hepatic endoplasmic reticulum stress by major urine protein 1(MUP1) and urine MUPs

Materials:

AML12 (mouse parenchymal liver cell line), HepG2 (human liver cancer cell line), mouse liver primary cells; recombinant MUP1 (supplied by the hong kong organism) and BCA method were used to determine protein concentration.

Urinary MUPs: random urine from C57BL/6J male mice was collected, centrifuged at 14000g in an ultrafiltration tube (millipore, 10kd) for 10 minutes at room temperature, inverted in a fresh centrifuge tube for 2 minutes at 1000g, and the concentrated urine was collected. 14000g of physiological saline is centrifuged for 10 minutes at room temperature for washing, and 1000g of physiological saline is centrifuged for 2 minutes in an inverted state for discarding the physiological saline. Repeatedly centrifuging to obtain concentrated urine. The concentration of urine MUPs was calculated by running the gel on SDS-PAGE, staining with Coomassie Brilliant blue for 15 minutes, destaining overnight to no background color, and measuring the gray level between 15-20KD by ChemiDoc exposure using recombinant MUP1 as a standard.

Whole transcriptome sequencing (RNAseq): shanghai, New Life Biotechnology, Inc.

The experimental method comprises the following steps:

firstly, extracting, intervening and sequencing primary hepatic cells:

1. taking 8-week-old male C57BL/6J mice, anesthetizing, spraying 75% alcohol to open the abdomen, fully exposing the abdominal cavity and the portal vein, puncturing the portal vein by adopting a 26G needle, pumping PBS preheated at 42 ℃ at a constant speed, and cutting off the inferior vena cava.

2. After the liver becomes white, 30mL of buffer solution 1 is perfused for 5min, 90-100mL of collagenase/buffer solution 2 is perfused for 10min, and the buffer solution 1 is perfused for 3 min.

3. The liver was removed and placed in pre-chilled buffer 2, the liver envelope was torn open with sterile forceps, shaken to obtain a cell suspension, filtered through a 70um cell strainer to obtain a single cell suspension.

Centrifugation at 4.500rpm for 5 minutes at 4 ℃ was performed, the buffer was aspirated off under negative pressure, the cells were resuspended in cell culture medium (high-glucose DMEM + 10% serum + 5% streptomycin), and the plates were counted.

5.37℃、5％CO₂Culturing for 6 hours in a cell culture box, after the cells adhere to the wall, sucking away the cell culture solution under negative pressure, and replacing with serum-free culture solution (high-glucose DMEM + 5% streptomycin) for starvation overnight.

6. Starvation was replaced with normal medium, and recombinant MUP1100ug/ml was added after 1 hour of acclimatization, and an equal amount of PBS was used as a control. After 12 hours of pretreatment, Tm was added, with an equal amount of DMSO as control.

7. After 6 hours of intervention, sucking away the culture solution under negative pressure, washing the cells once with PBS, adding trizol 1 ml/hole to crack the cells, extracting RNA, and performing whole transcriptome sequencing by using an Illumina high-throughput sequencing platform.

8. Data analysis was performed using Rstudio, and the ER stress gene was from KEGG mmu04141(https:// www.kegg.jp /). Referring to fig. 1, it is suggested that recombinant MUP1 is capable of improving hepatic primary cell endoplasmic reticulum stress.

Second, HepG2 cells were seeded in 12-well plates, and after the cell density reached 70%, urine MUPs100ug/ml were added as an experimental group, and an equivalent amount of 0.9% NaCl was used as a control group. After the experimental group and the control group are respectively pretreated for 24 hours, Tg (200nM) is respectively added to induce endoplasmic reticulum stress to serve as an experimental group A, B; an equal amount of DMSO was added as a control A, B. After the above groups were treated for 12h, the culture medium was aspirated, washed once with PBS and then blotted dry, 100 ul/well of precooled lysate was added, and after standing for 15 minutes on ice, cell lysate was collected. The above cell processing method can also be referred to fig. 2.

The method comprises the following steps:

(1) 12000g of cell lysate is centrifuged at 4 ℃ for 10 minutes, the supernatant is taken, and the precipitate is discarded.

(2) Each cell lysis supernatant concentration was trimmed by BCA quantification. 80ul of cell lysate was added to 20ul of loading buffer (5 x), boiled at 95 ℃ for 10min, mixed well and centrifuged briefly.

(3) SDS-PAGE (10% separation gel, 5% concentrated gel), fresh electrophoresis solution, and fresh transfer solution were prepared.

(4) Loading: marker added 4ul, 10ul on each well sample.

(5) Electrophoresis was carried out at 70V, and the loading band was adjusted to 120V after entering the separation gel.

(6) Stopping electrophoresis when the loading strip runs to the lowest end of the gel; and (5) rotating the die at a low temperature for 100V for 120 minutes.

(7) Applying primary antibody after washing the membrane by TBST:

BIP(CST,1:10000)，SEL1L(CST,1:2000)，IRE1α(CST,1:2000)，CHOP(CST,1:800)，actin(sigma,1:40000)。

(8) TBST washed membrane 5 minutes times 3 times.

(9) Applying a second antibody: goat anti-mouse IgG-HRP (Biorad, 1:5000), goat anti-rabbit IgG-HRP (Biorad, 1:5000), room temperature 1 h.

(10) TBST washed membrane 5 minutes times 3 times.

ECL development exposure (Biorad) and results analyzed.

Referring to FIG. 3, the observation of the endoplasmic reticulum stress-associated markers IRE1a, BIP, CHOP, SEL1L, ATF4, etc., indicates that urine MUPs are capable of inhibiting HepG2 endoplasmic reticulum stress.

Thirdly, AML12 cells were seeded in 12-well plates, and after the cell density reached 70%, urine MUPs100ug/ml were added as experimental group, and an equal amount of 0.9% NaCl was used as control group. After pretreatment for 24h in each of the experimental and control groups, Tg (200nM) was added to induce endoplasmic reticulum stress as experimental group C, D and DMSO was added in equal amounts as control C, D. After the above groups were treated for 12h, the culture medium was aspirated, washed once with PBS and then blotted dry, 100 ul/well of precooled lysate was added, and after standing for 15 minutes on ice, cell lysate was collected.

The method comprises the following steps:

(11) 12000g of cell lysate is centrifuged at 4 ℃ for 10 minutes, the supernatant is taken, and the precipitate is discarded.

(12) Each cell lysis supernatant concentration was trimmed by BCA quantification. 80ul of cell lysate was added to 20ul of loading buffer (5 x), boiled at 95 ℃ for 10min, mixed well and centrifuged briefly.

(13) SDS-PAGE (10% separation gel, 5% concentrated gel), fresh electrophoresis solution, and fresh transfer solution were prepared.

(14) Loading: marker added 4ul, 10ul on each well sample.

(15) Electrophoresis was carried out at 70V, and the loading band was adjusted to 120V after entering the separation gel.

(16) Stopping electrophoresis when the loading strip runs to the lowest end of the gel; and (5) rotating the die at a low temperature for 100V for 120 minutes.

(17) Applying primary antibody after washing the membrane by TBST:

BIP(CST,1:10000)，RE1α(CST,1:2000)，PERK(CST,1:2000)，CHOP(CST,1:800)，actin(sigma,1:40000)。

(18) TBST washed membrane 5 minutes times 3 times.

(19) Applying a second antibody: goat anti-mouse IgG-HRP (Biorad, 1:5000), goat anti-rabbit IgG-HRP (Biorad, 1:5000), room temperature 1 h.

(20) TBST washed membrane 5 minutes times 3 times.

ECL development exposure (Biorad) and results analyzed.

Referring to the expression of the endoplasmic reticulum stress-associated marker in FIG. 4, it is shown that urine MUPs are capable of inhibiting AML12 endoplasmic reticulum stress.

Four, HepG2 cells were seeded in 12-well plates, and after the cell density reached 70%, recombinant MUP1100ug/ml was added as an experimental group and an equal amount of PBS was used as a control group. After pretreatment of the experimental group and the control group for 24H, Tm (2.5ug/ml) or Tg (200nM) was added to induce endoplasmic reticulum stress, respectively, thereby forming experimental group E (MUP1+ Tm), experimental group F (MUP1+ Tg), experimental group G (PBS + Tm), and experimental group H (PBS + Tg): equal amounts of DMSO were added as control E (MUP1+ DMSO) and control F (PBS + DMSO). After 12h of treatment, the culture medium was aspirated, washed once with PBS and then blotted dry, 100 ul/well of precooled lysate was added, and after standing for 15 minutes on ice, cell lysate was collected. The above cell processing method can also be referred to fig. 5.

The method comprises the following steps:

(21) 12000g of cell lysate is centrifuged at 4 ℃ for 10 minutes, the supernatant is taken, and the precipitate is discarded.

(22) Each cell lysis supernatant concentration was trimmed by BCA quantification. 80ul of cell lysate was added to 20ul of loading buffer (5 x), boiled at 95 ℃ for 10min, mixed well and centrifuged briefly.

(23) SDS-PAGE (10% separation gel, 5% concentrated gel), fresh electrophoresis solution, and fresh transfer solution were prepared.

(24) Loading: marker added 4ul, 10ul on each well sample.

(25) Electrophoresis was carried out at 70V, and the loading band was adjusted to 120V after entering the separation gel.

(26) Stopping electrophoresis when the loading strip runs to the lowest end of the gel; and (5) rotating the die at a low temperature for 100V for 120 minutes.

(27) Applying primary antibody after washing the membrane by TBST:

BIP(CST,1:10000)，SEL1L(CST,1:2000)，actin(sigma,1:40000)。

(28) TBST washed membrane 5 minutes times 3 times.

(29) Applying a second antibody: goat anti-mouse IgG-HRP (Biorad, 1:5000), goat anti-rabbit IgG-HRP (Biorad, 1:5000), room temperature 1 h.

(30) TBST washed membrane 5 minutes times 3 times.

ECL development exposure (Biorad) and results analyzed.

Referring to fig. 6, the expression of SEL1L and the protein level of the BIP marker is observed, and the recombinant MUP1 is found to be capable of inhibiting HepG2 endoplasmic reticulum stress.

Fifthly, HepG2 cells are planted in 12-well plates, after the cell density reaches 70%, Tm (2.5ug/ml), Tm (5ug/ml) and Tg (200nM) are respectively added to induce endoplasmic reticulum stress to serve as experimental groups 1-3, and an equal amount of DMSO is used as a control. The treatment time was 12 hours and 24 hours, respectively. 100nM recombinant human insulin was added to the medium for 10min, and an equal amount of PBS was used as a control. The culture medium was aspirated, washed once with PBS and then blotted dry, 100 ul/well of precooled lysate was added, and after standing for 15 minutes on ice, cell lysate was collected.

The method comprises the following steps:

(31) 12000g of cell lysate is centrifuged at 4 ℃ for 10 minutes, the supernatant is taken, and the precipitate is discarded.

(32) Each cell lysis supernatant concentration was trimmed by BCA quantification. 80ul of cell lysate was added to 20ul of loading buffer (5 x), boiled at 95 ℃ for 10min, mixed well and centrifuged briefly.

(33) SDS-PAGE (10% separation gel, 5% concentrated gel), fresh electrophoresis solution, and fresh transfer solution were prepared.

(34) Loading: marker added 4ul, 10ul on each well sample.

(35) Electrophoresis was carried out at 70V, and the loading band was adjusted to 120V after entering the separation gel.

(36) Stopping electrophoresis when the loading strip runs to the lowest end of the gel; and (5) rotating the die at a low temperature for 100V for 120 minutes.

(37) Applying primary antibody after washing the membrane by TBST:

BIP(CST,1:10000)，p-AKT(CST,1:2000)，actin(sigma,1:40000)。

(38) TBST washed membrane 5 minutes times 3 times.

(39) Applying a second antibody: goat anti-mouse IgG-HRP (Biorad, 1:5000), goat anti-rabbit IgG-HRP (Biorad, 1:5000), room temperature 1 h.

(40) TBST washed membrane 5 minutes times 3 times.

ECL development exposure (Biorad) and results analyzed.

Referring to FIG. 7, the expression of p-AKT and BIP marker proteins was observed, which indicates that endoplasmic reticulum stress can cause HepG2 cell insulin resistance.

Six, HepG2 cells were seeded in 12-well plates, and after the cell density reached 70%, recombinant MUP1100ug/ml was added as an experimental group and an equal amount of PBS was used as a control group. After pretreatment of the experimental group and the control group for 24h, Tm (5ug/ml) or Tg (300nM) is added to induce endoplasmic reticulum stress as an experimental group M (MUP1+ Tm), an experimental group N (MUP1+ Tg), an experimental group K (PBS + Tm) and an experimental group J (PBS + Tg), an equal amount of DMSO is added as a control group M (MUP1+ DMSO) and a control group N (PBS + DMSO), and after 12h of drug intervention, 100nM recombinant human insulin is added to the culture medium for 10min to stimulate, and an equal amount of PBS is used as a control. The culture medium was aspirated, washed once with PBS and then blotted dry, 100 ul/well of precooled lysate was added, and after standing for 15 minutes on ice, cell lysate was collected. The above cell processing method can also be referred to fig. 8.

The method comprises the following steps:

(41) 12000g of cell lysate is centrifuged at 4 ℃ for 10 minutes, the supernatant is taken, and the precipitate is discarded.

(42) Each cell lysis supernatant concentration was trimmed by BCA quantification. 80ul of cell lysate was added to 20ul of loading buffer (5 x), boiled at 95 ℃ for 10min, mixed well and centrifuged briefly.

(43) SDS-PAGE (10% separation gel, 5% concentrated gel), fresh electrophoresis solution, and fresh transfer solution were prepared.

(44) Loading: marker added 4ul, 10ul on each well sample.

(45) Electrophoresis was carried out at 70V, and the loading band was adjusted to 120V after entering the separation gel.

(46) Stopping electrophoresis when the loading strip runs to the lowest end of the gel; and (5) rotating the die at a low temperature for 100V for 120 minutes.

(47) Applying primary antibody after washing the membrane by TBST:

BIP(CST,1:10000)，p-AKT(CST,1:2000)，actin(sigma,1:40000)。

(48) TBST washed membrane 5 minutes times 3 times.

(49) Applying a second antibody: goat anti-mouse IgG-HRP (Biorad, 1:5000), goat anti-rabbit IgG-HRP (Biorad, 1:5000), room temperature 1 h.

(50) TBST washed membrane 5 minutes times 3 times.

ECL development exposure (Biorad) and results analyzed.

Referring to fig. 9, the results show that the addition of recombinant MUP1, which has elevated p-AKT levels, suggests an increased insulin sensitivity, suggesting that recombinant MUP1 improves insulin resistance caused by HepG2 endoplasmic reticulum stress.

Seventhly, HepG2 cells were seeded in 6-well plates, and after the cell density reached 70%, 100ug/ml of urine MUPs were added as an experimental group, and an equivalent amount of 0.9% NaCl and a concentrated urine <10KD portion were used as a control group. After pretreatment for 24h, the test group and the control group are respectively added with Tg (300nM) to induce endoplasmic reticulum stress, namely test group I (urine MUPs + Tg), test group II (0.9% NaCl + Tg) and test group III (concentrated urine <10KD + Tg); equal amounts of DMSO were added as control I (urine MUPs + DMSO), control II (0.9% Nacl + DMSO), and control III (concentrated urine <10KD + DMSO). After 12h of drug intervention, 100nM recombinant human insulin was added to the medium for 10min, and an equal amount of PBS was used as a control. The culture medium was aspirated, washed once with PBS and then blotted dry, 100 ul/well of precooled lysate was added, and after standing for 15 minutes on ice, cell lysate was collected. The above cell processing method can also be referred to fig. 10.

The method comprises the following steps:

(51) 12000g of cell lysate is centrifuged at 4 ℃ for 10 minutes, the supernatant is taken, and the precipitate is discarded.

(52) Each cell lysis supernatant concentration was trimmed by BCA quantification. 80ul of cell lysate was added to 20ul of loading buffer (5 x), boiled at 95 ℃ for 10min, mixed well and centrifuged briefly.

(53) SDS-PAGE (10% separation gel, 5% concentrated gel), fresh electrophoresis solution, and fresh transfer solution were prepared.

(54) Loading: marker added 4ul, 10ul on each well sample.

(55) Electrophoresis was carried out at 70V, and the loading band was adjusted to 120V after entering the separation gel.

(56) Stopping electrophoresis when the loading strip runs to the lowest end of the gel; and (5) rotating the die at a low temperature for 100V for 120 minutes.

(57) Applying primary antibody after washing the membrane by TBST:

BIP(CST,1:10000)，p-AKT(CST,1:2000)，actin(sigma,1:40000)。

(58) TBST washed membrane 5 minutes times 3 times.

(59) Applying a second antibody: goat anti-mouse IgG-HRP (Biorad, 1:5000), goat anti-rabbit IgG-HRP (Biorad, 1:5000), room temperature 1 h.

(60) TBST washed membrane 5 minutes times 3 times.

ECL development exposure (Biorad) and results analyzed.

Referring to fig. 11, urine MUPs were able to improve insulin resistance caused by endoplasmic reticulum stress in HepG2 cells.

In conclusion, the urine MUPs and MUP1 can obviously improve the endoplasmic reticulum stress of mouse liver cells and can also improve the endoplasmic reticulum stress of human liver cells. Further, referring to fig. 9 and 11, urine MUPs and MUP1 improve insulin resistance caused by liver endoplasmic reticulum stress.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. Use of major urinary proteins as inhibitors of endoplasmic reticulum stress.

2. The use of claim 1, wherein said major urinary protein comprises major urinary protein 1 or urinary MUPs.

3. The use of claim 1, wherein endoplasmic reticulum stress comprises hepatic endoplasmic reticulum stress.

4. Application of main urinary protein in preparing medicine for improving endoplasmic reticulum stress is provided.

5. The use of claim 4, wherein the endoplasmic reticulum stress comprises hepatic endoplasmic reticulum stress.

6. The use as claimed in claim 4, wherein ERS inducer thapsigargin or tunicamycin is used to induce endoplasmic reticulum stress.

7. Application of main urinary protein in preparing medicine for treating diseases caused by liver endoplasmic reticulum stress.

8. The use of claim 7, wherein the disease comprises hepatic insulin resistance or diabetes.

9. A drug for improving endoplasmic reticulum stress, characterized in that the active ingredient of said drug comprises major urinary protein 1 and/or urinary MUPs.

10. The medicament of claim 9, wherein the medicament comprises a pharmaceutically acceptable carrier.