What are the uses of polypeptide drugs, let’s find out together!

Polypeptides are biologically active substances involved in various cellular functions in living organisms. With the rapid development of biology and cell biology technology, the scientific research of peptides has made amazing and epoch-making progress. It has been found that there are hundreds of thousands of polypeptides in living organisms, and it has been found that all cells can synthesize polypeptides. At present, the application of peptides is mainly concentrated on peptide drugs, peptide drug carriers, tissue engineering raw materials and peptide nutritional foods.

Antitumor Peptides

The occurrence of tumors is the result of the efficacy of various factors, but ultimately involves the regulation of the expression of oncogenes. Different tumors require different regulatory factors such as enzymes. Selecting specific small peptides to act on the regulatory factors required for tumorigenesis, and enclosing its active domain can avoid tumorigenesis. Nowadays, many tumor-related genes and tumor-causing regulatory factors have been discovered, and the selection of peptides that specifically bind to this target has become a new hot spot in the search for anti-cancer drugs.

Antiviral peptides

After virus infection, it generally goes through several steps such as adsorption (host cell), penetration, uncoating, nucleic acid replication, transcription and translation, and packaging. Blocking either whole process can prevent virus replication. The most effective antiviral drugs should be effective in the two stages of virus infection adsorption and nucleic acid replication. Therefore, the selection of antiviral drugs should focus on these two stages of virus replication. Virus infection attaches to cells based on binding to specific protein kinases on host cells, and relies on its own specific trypsin for protein production processing and nucleic acid replication. Therefore, polypeptides that bind to host cell protein kinases or polypeptides that can bind to active domains such as viral infection trypsin can be selected from the peptide pool for antiviral treatment.

Peptide-directed drugs

It has been known that many endotoxins (such as Pseudomonas aeruginosa exotoxin), cytokines (such as interleukin series products) have strong tumor cytotoxicity, but they can also damage normal cells in long-term or high demand. Combining the peptides that can specifically bind to tumor stem cells with this active factor can specifically concentrate this active factor at the tumor site, which can greatly reduce the application concentration of endotoxin and cytokines, and reduce their adverse effects. reaction.

Cytokine Mimic Peptide

In recent years, the use of known cytokine protein kinases to select cytokine-mimicking peptides from peptide pools has become a hot spot in scientific research around the world in recent years. The simulated peptides of various growth factors such as human hematopoietin, human thrombopoietin, human child growth hormone, human nervous system growth factor and interleukin 1 have been selected overseas. The amino acid sequence of this simulated peptide The amino acid sequence of the corresponding cytokine is not the same, but it has the activity of the cytokine and has the advantage of small relative molecular mass.

Antibacterial active peptides

When insects are stimulated by external conditions, many positive ion peptides with antibacterial activity have been formed. More than one hundred kinds of antibacterial peptides have been selected. In vitro tests have confirmed that several antibacterial peptides not only have strong sterilization and disinfection capabilities, but also kill tumor stem cells.

Peptides for cardiovascular and cerebrovascular diseases

Many green plant Chinese medicinal materials have the functions of lowering blood lipids, lowering blood lipids, and dissolving blood clots. They can be used not only as medicines, but also as health foods. However, in view of the uncertainty of its functional components, its application is greatly limited.

Other small peptides of medicinal value

In addition to the great progress made in the above-mentioned major aspects, small peptide drugs have also made some progress in many other aspects. For example, stiernberg et al. found that a synthetic peptide (TP508) peptide can promote the reconstruction of wound capillaries and accelerate the healing of deep skin wounds.

Polypeptides for diagnosis

The most important use of peptides in diagnostic reagents is to detect antigens of viruses, cells, chlamydia, cocci and other microbial strains and parasitic diseases such as cysticercosis and trypanosomes. Antigens have strong specificity and are easy to prepare, so the installed detection reagents have low false-negative rates and background reflections for detecting antigens, which is convenient for clinical application.

Polypeptide vaccines

Like nucleic acid vaccines, peptide vaccines are one of the most valued scientific research aspects in the vaccine research industry. In particular, many scientific studies have been carried out on polypeptide vaccines for viral infections. At present, there are no ideal vaccines for HIV and hepatitis C, two viral diseases that are very harmful to us. The analysis results of nucleic acid vaccines and peptide vaccines are encouraging.

Peptide drug carrier

As a drug carrier, polypeptide can not only be used as a decorative agent of drug carrier, but also can be used as a key component of drug carrier. Law et al. designed the peptide fragments linked by trypsin breakpoints to self-assemble in a suitable solvent to cover the drug in the liposomes, and when the targeted therapy trypsin is encountered, the breakpoint is broken, and the drug is released after the targeted therapy.

Peng Shiqi et al. used Arg-Gly-Asp-Ser (RGDS) tetrapeptide-decorated liposomes as drug carriers to direct thrombolysis. The platelet fibrinogen (FG) protein kinase ligand RGDS peptide was used as a homing device, coupled to liposomes encapsulating the urohormone UK. The carrier and the drug are connected by acid-sensitive chemical bonds, which can be degraded into endogenous Glu in nature or in the human body, which is not easy to cause deposits and side effects.

Tissue engineering raw materials

Some polymer peptides that do not have biological activity, such as polyaspartic acid, polylysine, polyglutamic acid, etc., because of their excellent biocompatibility, controllable degradation speed, decorability, design The advantages of ductility and predictability of structure have gradually become a new class of materials with application prospects in tissue engineering. Langer et al.

prepared poly(lactic acid bacteria-lysine) and thermally polymerized the RGD peptide onto the -NH2 of lysine in the polymer, which reasonably enhanced the cell adhesion ability of the polymer surface layer and got rid of the inactivity of the main chain. If the groups are not enough, the obtained tissue engineering scaffold raw material is not only conducive to cell recognition, but also suitable for cell growth.

Peptide nutritional food

As a new type of health food or food additive, active peptide food has unique characteristics and functions, and also has many advantages in nutrition, and has a wide application prospect in the food industry.

Cosmetic peptides

Tripeptides are growth factors, tetrapeptides have anti-inflammatory effects, pentapeptides can promote collagen to increase skin thickness, hexapeptides are botulinum toxins that can relax wrinkles, and nonapeptides can block melanin and have a whitening effect. According to the current analysis results, the peptides used in cosmetics are mainly peptides within six amino acid residues.

If the peptide chain exceeds six residues, the skin will be difficult to digest and absorb, so the number of amino acids that can be clinically applied overlaps. very high. In addition to some clinical and basic research on pentapeptide (Matrixyl) and hexapeptide (Argireline), some new peptides, especially constituent peptides, have a mystery in their efficacy.