A breast milk-derived polypeptide and its application in improving intestinal damage
By constructing IEPP1 self-assembled polypeptides targeting the intestinal epithelium and using nanovesicles to wrap it, the intestinal damage problem of NEC was solved, significantly improved intestinal damage in rats, and provided potential treatment and prevention methods for NEC.
Patent Information
- Application Number
- CN202410709288.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-03
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2044-06-03
AI Technical Summary
The prior art lacks effective treatment of necrotizing enterocolitis (NEC) and the mechanism of intestinal protective substances in breast milk is unknown, which leads to frequent sequelae in children and affecting quality of life.
By constructing a self-assembled polypeptide targeting the intestinal epithelium with therapeutic and traceability functions, it uses nanovesicles to wrap it to avoid digestive enzyme decomposition, and combines a Cy5 fluorescent probe to significantly improve intestinal damage.
Significantly improving intestinal damage in NEC rats provides potential therapeutic and preventive means for the preparation of drugs, health care products or food additives to improve intestinal damage.
Smart Images
Figure CN118496340B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of biomedicine technology, and in particular to a breast milk-derived polypeptide and its application in improving intestinal damage. Background Art
[0002] Necrotizing enterocolitis (NEC) is the most common and fatal gastrointestinal disease in neonatal intensive care units (NICUs). Clinically, it presents with abdominal distension, vomiting, diarrhea, hematochezia, and, in severe cases, shock and multisystem organ failure. Abdominal radiographs are characterized by cystic gas in the intestinal wall. Currently, there is a lack of effective treatment. While supportive care and late-stage surgery can save children's lives, clinical outcomes are poor. Some surviving children often suffer from sequelae such as short bowel syndrome, intestinal strictures, and long-term neurodevelopmental impairment, severely impacting their quality of life and placing a heavy economic burden on society and their families.
[0003] Breastfeeding is currently recognized as the only effective means of reliably preventing NEC. This suggests that breast milk contains intestinal protective substances. Studies have reported that breast milk may exert its protective effect against NEC by regulating intestinal immunity, lowering digestive tract pH, promoting gastrointestinal motility, and maintaining intestinal mucosal integrity, but the underlying mechanisms remain unclear. Summary of the Invention
[0004] In order to overcome the shortcomings and deficiencies in the prior art, the present invention aims to provide a human milk-derived polypeptide and its application in improving intestinal damage.
[0005] The object of the present invention is achieved through the following technical solution: a human milk-derived polypeptide, the amino acid sequence of the human milk-derived polypeptide is shown in SEQ ID NO.1.
[0006] Preferably, the self-assembling polypeptide is formed by connecting the breast milk-derived polypeptide according to claim 1 with a targeting group.
[0007] Preferably, the targeting group is an intestinal epithelial cell targeting and inflammatory response group.
[0008] Preferably, the targeting group is further connected to a Cy5 fluorescent probe.
[0009] Preferably, the structural formula of the self-assembling polypeptide is as follows:
[0010] Among them, IEPP1 is a breast milk-derived polypeptide.
[0011] Preferably, the outer side of the self-assembling polypeptide is wrapped with nanovesicles.
[0012] Another object of the present invention is achieved through the following technical solution: use of a human milk-derived polypeptide in the preparation of a medicine, health product or food additive for improving intestinal damage.
[0013] Preferably, the intestinal injury is necrotizing enterocolitis.
[0014] Another object of the present invention is achieved through the following technical solution: use of a self-assembling polypeptide in the preparation of medicines, health products or food additives for improving intestinal damage.
[0015] Preferably, the intestinal injury is necrotizing enterocolitis.
[0016] The beneficial effects of the present invention are that the breast milk exosome-derived polypeptide IEPP1 can significantly improve intestinal damage in rats with NEC. By linking a targeting gene with the fluorescent probe Cy5, a nano-encapsulated, intestinal epithelial-targeting IEPP1 self-assembling polypeptide with therapeutic and tracing functions was successfully constructed. This can be used to prepare drugs, health products, or food additives to improve intestinal damage, such as necrotizing enterocolitis. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 Figure 3 is the protective effect of IEPP1 on NEC animal model, where A is HE staining of rat intestine after IEPP1 intervention (200X), and B is the NEC intestinal pathology score.
[0018] Figure 2 The basic characteristics of nanovesicles encapsulating M-IEPP1 (Bar=200 nm).
[0019] Figure 3 This is a preliminary functional exploration of the nanovesicle-encapsulated self-assembling peptide M-IEPP1 at the cellular / animal level, where A shows the entry of nanovesicle-encapsulated M-IEPP1 into cells (200X), B shows the effect of nanovesicle-encapsulated M-IEPP1 on the proliferation of NEC cell models, C shows the in vivo distribution of nanovesicle-encapsulated M-IEPP1, and D shows the effect of nanovesicle-encapsulated M-IEPP1 on intestinal damage in NEC animal models (200X). DETAILED DESCRIPTION
[0020] In order to facilitate the understanding of those skilled in the art, the following embodiments and accompanying drawings are provided. Figure 1-3 The present invention is further described, and the contents mentioned in the embodiment are not intended to limit the present invention.
[0021] Example 1: Breast milk exosome-derived polypeptide IEPP1 can significantly improve intestinal damage in NEC rats
[0022] After the applicant realized the health effects of breast milk, with the help of the established breast milk active ingredient screening platform, they studied whether breast milk-derived active small molecules (exosomes, peptides, lipids, etc.) may be important components that mediate the health effects of breastfeeding, and found that breast milk exosomes and internal components of bioactive peptides have a protective effect on the health of offspring. Based on the fact that active small molecules derived from breast milk must be digested and absorbed by the gastrointestinal tract, and only a small part can escape the influence of intestinal enzymes, the applicant focused on the health prevention and treatment effects of breast milk-derived exosomes and their endogenous active substances on NEC. It is known that small molecule bioactive peptides are one of the important components of exosomes, which have functions such as regulating immunity, anti-infection, and promoting growth and development. The applicant has previously confirmed that breast milk exosomes can promote the proliferation / migration of normal human intestinal epithelial cells (FHC) and intestinal epithelial cells in NEC animal models, and the effect of premature infant breast milk exosomes is better. After comparative analysis of the peptidomics of breast milk exosomes from premature infants and full-term infants, the applicant selected a previously unreported peptide SEQ ID NO.1: QAIAENRADAVTLDGGFIYEAGLAPYKLRPVAA that is abundant in premature infant breast milk exosomes and has the potential to maintain the integrity of the intestinal epithelium for in-depth research, and preliminarily named it IEPP1 (Intestinal epithelial protective peptide 1). Using the NEC animal model as the research object, we explored the function of IEPP1. Histopathological results showed that the addition of IEPP1 treatment to the NEC group during modeling could partially alleviate the degree of intestinal epithelial damage (see Figure 1 ).
[0023] Example 2 Construction of self-assembling polypeptide M-IEPP1
[0024] To enable IEPP1 to target the digestive tract epithelium and exert its function, we linked IEPP1 to a Cy5 fluorescent probe and an intestinal epithelial cell targeting and inflammatory response group, successfully constructing a nano-encapsulated, intestinal epithelium-targeted, therapeutic, and tracing IEPP1 self-assembling peptide, M-IEPP1 (Modified-IEPP1). Its structural formula is:
[0025]
[0026] To avoid digestion by digestive enzymes, we used nanovesicles to encapsulate M-IEPP1 (see Figure 2 ).
[0027] Example 3 Protective Effect of Self-Assembling Polypeptide M-IEPP1 on Intestinal Epithelial Cell Damage in NEC Model
[0028] After incubation of nanovesicle-encapsulated M-IEPP1 with human intestinal epithelial cells FHC for 12 hours, significant fluorescence was observed in the cells; cell proliferation experiments showed that M-IEPP1 weakened the LPS-induced inhibition of intestinal epithelial cell proliferation. After oral administration of nanovesicle-encapsulated M-IEPP1 to nude mice, visible fluorescence was still observed in the digestive organs 6 hours later; pathological sections showed the protective effect of M-IEPP1 on intestinal epithelial cell damage in the NEC model (see Figure 3 ).
[0029] Therefore, we have preliminarily obtained experimental evidence that nanovesicle-encapsulated M-IEPP1 can successfully enter the intestinal epithelium to promote cell proliferation and weaken intestinal epithelial damage.
[0030] In summary, we have identified a previously unreported human milk exosome-derived peptide, IEPP1, that significantly improves intestinal damage in rats with NEC. By linking a targeting gene with the fluorescent probe Cy5, we successfully constructed a nanoparticle-encapsulated, intestinal epithelial-targeted, self-assembling IEPP1 peptide with both therapeutic and tracing functions. This peptide could be used to develop drugs, health supplements, or food additives to improve intestinal damage, such as necrotizing enterocolitis.
[0031] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention can also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the scope of protection of the present invention.
Claims
1. A self-assembling polypeptide, characterized in that: The self-assembling polypeptide is formed by connecting a breast milk-derived polypeptide with an amino acid sequence as shown in SEQ ID NO.1 and a targeting group, wherein the targeting group is an intestinal epithelial cell targeting and inflammatory response group, and the targeting group is also connected to a Cy5 fluorescent probe, and the outer side of the self-assembling polypeptide is wrapped with a nanovesicle; The structural formula of the self-assembling polypeptide is as follows: Among them, IEPP1 is a polypeptide derived from breast milk.
2. Use of a self-assembling polypeptide according to claim 1 in the preparation of a drug for improving intestinal damage, characterized in that: The intestinal damage is necrotizing enterocolitis.