阅读说明：本技术 间充质干细胞外泌体在制备用于预防或治疗1型糖尿病及其相关疾病药物中的应用 (Application of mesenchymal stem cell exosome in preparation of medicine for preventing or treating type 1 diabetes and related diseases thereof ) 是由 段武 于 2021-09-14 设计创作，主要内容包括：本发明提供了一种miRNA在治疗1型糖尿病及其相关疾病药物中的应用,其特征在于,所述miRNA为miR-199a-5p。首次提出了miR-199a-5p在制备1型糖尿病及其相关疾病药物中的新用途,以及在制备诱导T细胞分化制剂中的新用途；可有效降低1型糖尿病引起的血糖升高,在一定程度上改善胰岛炎病症,达到预防和治疗1型糖尿病的作用；采用miR-199a-5p作为有效成分,药物靶向性高,具有微量高效,安全可靠,毒性低的优势。(The invention provides application of miRNA in medicines for treating type 1 diabetes and related diseases thereof, which is characterized in that the miRNA is miR-199a-5 p. The new application of miR-199a-5p in the preparation of medicaments for treating type 1 diabetes and related diseases thereof and the preparation of medicaments for inducing the type 1 diabetes and the related diseases are provided for the first time Novel use in T cell differentiation preparations; can effectively reduce the blood sugar rise caused by the type 1 diabetes, improve the insulitis disease to a certain extent, and achieve the effect of preventing and treating the type 1 diabetes; the miR-199a-5p is used as an active ingredient, and the drug targeting property is high, and the drug has the advantages of trace amount, high efficiency, safety, reliability and low toxicity.)

Application of miR-199a-5p in preparation of medicines for preventing or treating type 1 diabetes and related diseases thereof.

2. The use according to claim 1, wherein the drugs for preventing or treating type 1 diabetes and related diseases thereof comprise hypoglycemic agents, islet function impairment repairing agents and/or induction agentsA cell differentiation preparation.

3. Use according to claim 2, wherein the induction isThe cell differentiation agent is for inhibitingThe preparation can promote the differentiation of the cells to Th1 cells and Th17 cells and Th2 cells and Treg cells.

4. The use of claim 3, wherein miR-199a-5p is induced by targeted down-regulation of expression of hypoxia inducible factor Hif-1 alphaAnd (4) cell differentiation.

5. The use of any one of claims 1 to 4, wherein miR-199a-5p is placed in a vector for use.

6. The use according to claim 5, wherein the vector is selected from one or more of exosomes, viral vectors, high molecular polymer vectors, liposomes; preferably, the vector is an exosome.

7. The use of claim 6, wherein the exosomes are exosomes derived from bone marrow mesenchymal stem cells.

8. The use of claim 7, wherein the bone marrow mesenchymal stem cell exosomes are extracted by the following method:

culturing the bone marrow mesenchymal stem cells to P5 generation, collecting cell culture supernatant, and extracting exosome in the supernatant by ultracentrifugation and/or precipitation.

9. A pharmaceutical preparation for preventing or treating type 1 diabetes and related diseases thereof, which is characterized by comprising bone marrow mesenchymal stem cell exosomes internally containing miR-199a-5 p.

10. The pharmaceutical formulation of claim 9, wherein the pharmaceutical formulation is in the form of an injectable formulation.

Technical Field

The application relates to the technical field of biomedicine, in particular to application of miR-199a-5p in preparation of a medicine for preventing or treating type 1 diabetes and related diseases thereof.

Background

Type 1 diabetes (T1DM) is an autoimmune disease, often with acute onset, often accompanied by serious complications such as ketoacidosis.

The pathogenesis of T1DM is mainly abnormal proliferation and activation of in vivo reactive T cells, a large amount of proinflammatory cells Th1 and Th17 are expanded, and the numbers of inflammation-inhibiting regulatory T cells (Tregs) and Th2 cells are relatively insufficient, so that the proportion of Th1/Th2 and Th17/Treg cells is unbalanced, periinsulitis is formed, and further, the damage of islet beta cells, the reduction of insulin secretion and the increase of blood sugar are caused. Therefore, the effective inhibition of proinflammatory Th1 and Th17 cell proliferation and the increase of anti-inflammatory Treg cell content in NOD mice are the core problems of reducing insulitis and preventing T1DM diseases, namely, the correction of immune imbalance state is the key point of preventing and treating T1 DM.

The NOD mouse is a classical spontaneous type 1 diabetes model, the pathogenesis and the process of the mouse are very similar to those of human T1DM, the NOD mouse can well simulate the disease process of T1DM, is a currently accepted T1DM disease model, and is widely used for related researches.

miRNA is a highly conserved, non-coding small RNA, a regulator of gene expression that is widely present in organisms. As an important component of exocrine bodies, mirnas have become key regulators of the pathogenesis of various diseases, including immune system diseases. Evidence shows that the miRNA has the advantages of strong targeting property, trace amount and high efficiency compared with other therapeutic drugs.

However, the prior art fails to disclose relevant reports about the applications of miRNA in preventing or treating type 1 diabetes and related conditions thereof.

Disclosure of Invention

In order to solve the problems, the invention provides application of miR-199a-5p in preparation of a medicine for preventing or treating type 1 diabetes and related diseases thereof.

Further, the medicament for preventing or treating type 1 diabetes and related diseases comprises a hypoglycemic agent, an islet function damage repairing agent and/or an induction agentT cell differentiation preparation.

Further, the induction is carried outThe T cell differentiation preparation is used for inhibitingT cells to Th1 cells and Th17 cellsDifferentiation and promotion of differentiation into Th2 cells and Treg cells.

Furthermore, miR-199a-5p induces expression induction of hypoxia inducible factor Hif-1 alpha through targeted down-regulationT cell differentiation.

On the other hand, the miR-199a-5p is placed in a carrier for application.

Further, the carrier is selected from one or more of exosome, viral vector, high molecular polymer carrier and liposome; preferably, the vector is an exosome.

Further, the exosome is an exosome derived from a bone marrow mesenchymal stem cell.

Further, the bone marrow mesenchymal stem cell exosome is extracted by the following method:

culturing the bone marrow mesenchymal stem cells to P5 generation, collecting cell culture supernatant, and extracting exosome in the supernatant by ultracentrifugation and/or precipitation.

In the embodiment, BM-MSC exosomes are used as carriers of miR199a-5p for experiments, because the BM-MSC exosomes are considered to be easy to degrade by RNA enzymes in vivo due to the consideration of instability of RNA molecules, the carriers of miR199a-5p can be selected from exosomes which have natural advantages and are secreted by other tissue cells like the BM-MSC exosomes, and can also be selected from extracellular vesicle natural nanoparticles, viral vectors, high polymer vectors and liposomes with the same advantages, which is not limited herein.

In another aspect, a pharmaceutical preparation for preventing or treating type 1 diabetes and related diseases thereof, wherein the pharmaceutical preparation comprises bone marrow mesenchymal stem cell exosomes internally containing miR-199a-5 p.

Further, the dosage form of the pharmaceutical preparation is an injection preparation.

The invention has the following beneficial effects:

the application firstly provides miR-199a-5p, in particular to a BM-MSC exosome containing miR-199a-5p for inhibiting Hif-1 alpha expression through targeted down-regulationSystem for makingThe T cells are differentiated to Th1 and Th17 cells and promoted to be differentiated to Th2 and Treg cells, so that the effects of relieving insulitis and preventing diabetes attack of NOD mice are achieved, and the NOD mice can have new application in preparing medicines for treating type 1 diabetes and related diseases, and can be used for preparing preparations for reducing blood sugar, repairing preparations for pancreatic island function damage and inducing the diabetes to be treatedNovel use of T cell differentiation agent; can effectively reduce the blood sugar rise caused by the type 1 diabetes, improve the insulitis disease to a certain extent, and achieve the effect of preventing and treating the type 1 diabetes; the miR-199a-5p is used as an active ingredient, and the drug targeting property is high, and the drug has the advantages of trace amount, high efficiency, safety, reliability and low toxicity.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

FIG. 1 is a diagram of action mechanism patterns of BM-MSC exosomes containing miR-199a-5p for reducing the incidence rate of diabetes mellitus in NOD mice;

FIG. 2 is a flow chart of an experiment that BM-MSC exosomes containing miR-199a-5p reduce the incidence rate of NOD mouse diabetes;

FIG. 3 is transmission electron micrograph of exosome vesicles (arrows) released by BM-MSC cells: the scale in the figure is 100 nm;

FIG. 4 is a statistical plot of exosome particle size analysis;

FIG. 5 is a graph of the result of Western blot identification of BM-MSC exosome marker proteins CD9 and CD 63;

FIG. 6 is a NOD mouse survival graph;

FIG. 7 is a statistical chart of the conditions of insulitis in NOD mice;

FIG. 8 is a HE staining pattern of pancreatic tissue from NOD mice: the scale in the figure is 50 μm;

FIG. 9 is a graph showing the results of flow cytometry on spleen lymphocytes of NOD mice;

FIG. 10 shows that the CCK8 method detects the stimulation of BM-MSC exosomes to CD3/CD28Graphs of the results of the effects of T cell proliferation, P < 0.01, P < 0.001;

FIG. 11 shows the isolation and extraction of spleen from C57BL/6 miceT cell result graphs;

FIG. 12 is a graph showing the results of quantitation of miRNA in BM-MSC exosomes;

FIG. 13 isA miRNA quantitative result graph is obtained by co-incubating T cells and BM-MSC exosomes;

FIG. 14 isWestern blot identification result chart of expression quantity of Hif-1 alpha in T cells;

FIG. 15 isq-PCR results of expression of Hif-1. alpha. in T cells, # P < 0.01, # P < 0.05.

Detailed Description

In order to more clearly explain the overall concept of the present application, the following detailed description is given by way of example in conjunction with the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

Laboratory instruments and reagents are known in the art and are commercially availableAnd (5) obtaining the product. Among them, C57BL/6 mice, NOD/ltj mice were supplied by Beijing Wakaukang Bio Inc., and ultracentrifuges were supplied by Beckman coulter company,t cell magnetic bead sorting kits were supplied by american and whirlpool.

Example 1 extraction and characterization of mouse BM-MSC

(1) Separation of the femur: c57BL/6 mice of about 4 weeks of age were selected, sacrificed with excess anesthetic, soaked in 75% ethanol for 5 minutes, then transferred to a clean bench and the bilateral femurs and tibiae of the mice were separated under sterile conditions.

(2) Obtaining bone marrow: the ends of the femur were cut off, the marrow cavity was exposed, the cavity was flushed with complete medium (79% DMEM/F12 medium + 20% FBS + 1% double antibody) drawn up with a 5mL syringe, and the bone marrow was harvested by repeated tapping 2-3 times.

(3) Plate preparation: plating was performed on the basis of one of six well plates, approximately 2.5mL per well, inoculated with marrow fluid extracted from one femur. Placing at 37 ℃ and 5% CO₂The cells were cultured overnight in a cell incubator and replaced with fresh complete medium after 24 hours. The culture was performed in the subsequent culture using 10% FBS + 1% double antibody DMEM/F12 complete medium.

(4) Passage: when the cell fusion degree reaches 90%, passage can be carried out. Washing the cell surface with PBS, adding appropriate pancreatin to digest the cells, and transferring to 25cm per well²Subculturing is carried out according to the principle of a culture flask. Passage 3-4 cells were selected for subsequent experiments.

Example 2 extraction and characterization of BM-MSC exosomes

After culturing BM-MSC for P5 generation, cell culture supernatant (using fetal calf serum without exosome) was collected and exosomes were extracted from the culture medium by ultracentrifugation.

The specific operations in this embodiment are: the CM blood culture supernatant was taken and put into a 50mL centrifuge tube, and centrifuged for 30min at 3000 g. And (4) putting the supernatant into a high-speed centrifuge tube, and centrifuging for 30min at 10000g to obtain the supernatant. The supernatant was filtered through a 0.22 μm filter. The filtrate was loaded into 38.5mL ultracentrifuge tubes and centrifuged at 110000 g for 70 min. After carefully discarding the supernatant, BM-MSC exosomes were obtained and resuspended in PBS, saline or liquid medium for future use.

The exosome morphology was observed by (1) electron microscopy, and the observation results are shown in fig. 3. (2) The size of the exosome vesicle can be known by analyzing the particle size of the exosome by the NTA method, and the analysis result is shown in figure 4. (3) Western Blot detects the exosome marker proteins CD9, CD63 and TSG101, and the detection results are shown in FIG. 5.

As can be seen from the results shown in fig. 3 to 5, high-quality exosomes were obtained by the above-described method.

Example 3 Effect of BM-MSC exosomes on the onset of diabetes in NOD mice

BM-MSC exosomes were injected tail vein into 3-week-old female NOD mice (150 μ g/mouse) and 1 time each at 5, 7 and 9 weeks of age of the mice, at the same dose as before, for the following experiments, respectively:

(1) monitoring blood glucose: the incidence condition of the mice is observed by taking continuous 2 times of random blood sugar of more than or equal to 250mg/dl as the incidence standard of diabetes of the NOD mice, the incidence statistical result of the mice is shown in figure 6, the control group of the mice without the BM-MSC exosomes can be obtained from the figure at 30 weeks without blood sugar, and 80% of the experimental group of the mice with the BM-MSC exosomes can still keep the blood sugar normal without incidence phenomenon, so that the BM-MSC exosomes can be obtained to obviously reduce the incidence of the NOD mice.

(2) Serological indexes: the islet function of the NOD mice is detected by an intraperitoneal glucose tolerance test (IPGTT) when the mice are 12 weeks old, the statistical result of the insulitis of the mice is shown in figure 7, and the figure shows that the number and the degree of the insulitis of the mice in a control group without the BM-MSC exosomes are more serious than those of the mice in an experimental group with the BM-MSC exosomes, so that the BM-MSC exosomes can obviously reduce the islet score of the NOD mice and relieve and treat the insulitis of the NOD mice.

(3) Histology of islets: pancreatic tissues are taken when the mice are 12 weeks old, HE staining is carried out to observe the morphology of the pancreatic tissues, immunofluorescence is carried out to detect CD3 and insulin expression, lymphocyte infiltration and insulin secretion conditions in the pancreatic islets of the mice in each group are evaluated to judge the degree of insulitis and the function of the pancreatic islets, HE staining results of the pancreatic tissues of the mice are shown in figure 8, and the HE staining of the pancreatic tissues of the NOD mice can be obtained from the figure to find that BM-MSC exosomes obviously reduce the infiltration of the pancreatic islet inflammatory cells, and the BM-MSC exosomes can relieve and treat the insulitis of the NOD mice.

Example 4 BM-MSC exosomes influence the pathogenesis of diabetes in NOD mice

(1) Construction of stable CD63-GFP-MSC transformants: a packaging CD63-GFP-Puro lentivirus is constructed, mouse BM-MSC (MOI is 10) is transfected, amplification culture is carried out after puromycin (2 mu g/mL) resistance screening, expression of CD63 and GFP is detected through Western Blot, and a CD63-GFP-MSC stable transformant is successfully constructed.

(2) Extracting a CD63-GFP-MSC stable transformant exosome by an ultracentrifugation method, injecting a CD63-GFP-MSC stable transformant exosome (150 mu g/mouse) into a 3-week-old female NOD mouse through a tail vein, selecting two time points of 12 hours and 24 hours, taking a mouse spleen, observing GFP fluorescence distribution in the spleen by a fluorescence microscope after ice-freezing slicing, and detecting the spleen by flow cytometryGFP expression in T cells.

(3) BM-MSC exosomes are injected into female NOD mice (150 mu g/mouse) with the age of 3 weeks in tail vein, and are injected 1 time at the age of 5 weeks, 7 weeks and 9 weeks respectively, mouse spleen cells are obtained when the mice are 12 weeks old at the same dose, cell ratios of Th1(CD4+ IFN-gamma +), Th2 (CD4+ IL-4+), Th17(CD4+ IL-17+) and Treg (CD4+ CD25+ FOXP3+) are detected by flow cytometry, and the detection result is shown in figure 9, and the BM-MSC exosomes obviously reduce the cell ratios of Th1 and Th17 in the NOD mice and increase the cell ratios of Th2 and Treg.

Example 5Uptake of BM-MSC exosomes by T cells

(1) Use beautiful and gentleT cell magnetic bead sorting kit for separating and extracting spleen single cell suspension from 6-week-old male C57BL/6 mouseT (CD3+ CD4+ CD25-CD62L + CD44low /) cells. CD63-GFP-MSC stable transformant derived exosome andafter T cells are incubated for 12h and 24h, the cells are fixed by 4% paraformaldehyde and observed by a fluorescence microscopeDistribution of green fluorescence in T cells, detectionT cells take up CD63-GFP-MSC exosome status. Method for detecting stimulation of BM-MSC exosomes to CD3/CD28 by CCK8 methodThe effect of T cell proliferation, the results of which are shown in FIG. 10, show that BM-MSC exosomes can be dose-dependently inhibitedT cells proliferate.

(2)T cells were plated at a density of 0.25 x 10^ 6/well in 96-well plates at: th1(anti-CD3: 5. mu.g/ml + anti-CD28: 1. mu.g/ml + IL-2:20ng/ml + IL-12:20ng/ml + anti-IL-4: 10. mu.g/ml), Th2(anti-CD3: 5. mu.g/ml + anti-CD28: 1. mu.g/ml + IL-2:20ng/ml + IL-4:100 ng/ml + anti-IFN-gamma: 10. mu.g/ml + anti-IL-12: 10. mu.g/ml), Th17(anti-CD3: 5. mu.g/ml + anti-CD28: 1. mu.g/ml + IL-2:20ng/ml + anti-IL-4: 10. mu.g/ml + anti-IFN-gamma: 10. mu.g/ml), Treg (anti-CD3: 5. mu.g/ml + CD 28. mu.g/ml + IL-4: 10. mu.g/ml + anti-IL-gamma: 10. mu.g/ml) ng/ml + TGF-beta: 5ng/ml) cell induced differentiation culture system, incubating with exosomes for 5 days, adding 0ug, 5ug, 10ug and 20ug BM-MSC exosomes into the system respectively to make the final volume be 250 uL/well (96-well plate), separating and extracting from spleen of C57BL/6 mouse by magnetic bead sortingT cells (CD4+ CD25-), and the results of separation are shown in FIG. 11, and obtainedT cells and detecting the proportion of Th1/Th2/Th17/Treg cells by flow cytometry.

(3) Western Blot and q-PCR detectionChanges in the levels of Hif-1 α protein and mRNA during T cell differentiation.

(4) Design of synthetic packaging Hif-1. alpha. overexpressing adenovirus, transfected intoIn T cells, qPCR and Western Blot validationAfter Hif-1 alpha is over-expressed in T cells, BM-MSC exosome pairs are observed under a Th1/Th2/Th17/Treg induced differentiation culture systemThe influence of the T cells on the differentiation of the Th1, the Th2, the Th17 and the Treg cells can obtain BM-MSC exosomes to reduce the proportion of the Th1 and the Th17 cells in the spleen of NOD mice and increase the proportion of the Th2 and the Treg cells.

Example 6 detection of expression level of miRNA in BM-MSC exosomes and Mimics screening and validation

Extracting total RNA of BM-MSC exosomes, performing small RNA sequencing on an Illumina HiSeq2500 platform, and quantifying miRNA expression abundance by a qPCR method.

Selecting miRNA at the first 20 of expression amount, combining Hif-1 alpha gene to carry out bioinformatics analysis and literature analysis, searching miRNA for regulating expression of Hif-1 alpha gene in BM-MSC exosomes, carrying out comparative analysis with the miRNAs (miR-135a, miR-138, miR-1, miR-210, miR-199a-5p, miR-122 and miR-433), screening and verifying the selected miRNAs one by using mimics, further determining and verifying expression of miR-199a-5p in BM-MSC exosomes, and obtaining the result as shown in figure 12, wherein miR-199a-5p, miR-122 and miR-135a have rich content in BM-MSC exosomes, and the content of miR-199a-5p is the highest.

Example 7 pairs of miR-199a-5pEffect of T cells

BM-MSC exosomes andafter the T cells are incubated for 24h, the content of miR-199a-5p in the cell lysate is detected by qPCR (quantitative polymerase chain reaction), as shown in figure 13,after the T cells and BM-MSC exosomes are incubated for 24h, the miR-199a-5p level in cell lysate is obviously increased.

Adding 20 μm/L GW4869 into BM-MSC to inhibit cell vesicle release, extracting its exosome, and mixing withqPCR detection after 24h of T cell co-incubationThe content of miRNA-199a-5p in the T cell lysate, and the experiment can clearly determineThe increased miRNA-199a-5p in the T cell is derived from BM-MSC exosomes.

Example 8 obtaining potential complementary binding site of miR-199a-5p and 3' UTR of Hif-1 alpha gene by microRNA target gene prediction software Targetscan

Potential complementary binding sites of miR-199a-5p and 3' UTR of Hif-1 alpha gene are obtained through microRNA target gene prediction software Targetscan (http:// www.targetscan.org /); PCR amplification is carried out on a 3 'UTR sequence and a 3' UTR mutation sequence of the Hif-1 alpha gene, the sequences are respectively cloned to luciferase report vectors (recombinant luciferase report plasmids), the two plasmids and miR-199a-5p mimics are respectively transfected to 293-T cells, the luciferase activity of the cells is detected by collecting the cells through a dual-luciferase report system after 48 hours, and the target regulation relation between Hif-1 alpha and miR-199a-5p is determined.

Example 9 pairs of miR-199-5p mimicsEffect of T cell differentiation

Designing and synthesizing miR-199-5p mimics, and detecting miR-199-5p mimics pairs by flow cytometry under a Th1/Th2/Th17/Treg cell induced differentiation culture systemEffects of T cell differentiation. The obtained miR-199-5p can reduce the proportion of Th1 and Th17 cells in the spleen of an NOD mouse and increase the proportion of Th2 and Treg cells.

EXAMPLE 10 cellular level study of miRNA-199a-5p pairsEffect of T cell Hif-1 alpha expression and differentiation

Designing and synthesizing miRNA-199a-5p silencing oligonucleotide chain (anti-miRNA-199a-5p oligonucleotide) and control oligonucleotide (NC), transfecting FECTTM CP transfection reagent into BM-MSC, extracting exosome, and respectively naming BM-MSC-exo^{anti-miR-199a-5p}And BM-MSC-exo^NC. BM-MSC-exo detection by CCK8 experiment^{anti -miR-199a-5p}To pairThe effects of T cell proliferation; respectively detecting BM-MSC-exoanti-miR-199a-5p pairs by flow cytometry, Western blot and qPCR (quantitative polymerase chain reaction) under a Th1/Th2/Th17/Treg induced differentiation culture systemEffects of T cell differentiation, Hif-1. alpha. protein and mRNA expression.

Western blot detection of influence of BM-MSC-exoanti-miR-199a-5p on Hif-1 alpha protein, detection of knotsAs shown in FIG. 14, BM-MSC exosomes could be significantly down-regulated from the mapExpression of T cell Hif-1 alpha, and reduction of exosomes after silencing miR-199a-5p by BM-MSCThe effect of T cell Hif-1. alpha. expression was abolished.

The influence of BM-MSC-exoanti-miR-199a-5p on mRNA expression is detected by qPCR, the detection result is shown in figure 15, and BM-MSC exosomes obtained from the figure can be remarkably reducedExpression of T cell Hif-1 alpha, and reduction of exosomes after silencing miR-199a-5p by BM-MSCThe effect of T cell Hif-1. alpha. expression was abolished.

Example 11 animal level study of the Effect of miRNA-199a-5p on the onset of diabetes in NOD mice

BM-MSC-exo^{anti-miR-199a-5p}And BM-MSC-exo^NCThe tail vein was injected into NOD mice of 3 weeks of age at a dose of 150. mu.g/mouse, and the mice were injected 1 more times each at 5 weeks of age, 7 weeks of age, and 9 weeks of age, and the onset of diabetes was observed in the mice at the same dose, and the insulitis, spleen T lymphocyte subsets (Th1, Th2, Th17, Treg ratio), and spleen cell Hif-1. alpha. expression were observed in the mice at 12 weeks of age. Observation results show that BM-MSC-exo injection^NCCan be used for relieving diabetic attack in NOD mice by injecting BM-MSC-exo^{anti-miR-199a-5p}The onset of diabetes of NOD mice cannot be reduced, so that miRNA-199a-5p can play an important role in treating and preventing type 1 diabetes.

In conclusion, the invention provides a new application of miRNA-199a-5p in preparing a type 1 diabetes medicine and a new application in preparing an insulitis medicine, and the miRNA-199a-5p can effectively inhibit the proliferation of proinflammatory Th1 and Th17 cells in NOD mice, increase the content of inflammation-inhibiting Treg cells, correct the immune imbalance state, reduce blood sugar and achieve the purpose of treating and preventing type 1 diabetes.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.