ABSTRACT
Antimicrobial peptides (AMPs) distribute widely in many organisms. As an important part of the nonspecific immune functions of organisms, AMPs can not only protect the body from bacteria, fungi, parasites, viruses, and other pathogens, but also have the functions of mediating catalysis, apoptosis, immune regulatory activity, accelerating wound healing and osteogenetic effects. AMPs have become a research focus for antimicrobial coating on titanium implant surface and have shown a promising prospect. In this paper, we reviewed the antimicrobial mechanism, loading method, and application status of AMPs applied on titanium implant surface.
ABSTRACT
BACKGROUND: As a potential candidate that can be extracted from natural sources and used to fight antibiotic-resistant bacteria, antimicrobial peptides have attracted extensive attention of scientists. Familiarity with the antimicrobial mechanism of antimicrobial peptides is conducive to the clinical application of antimicrobial peptides. OBJECTIVE: To review the advance in research of antimicrobial mechanism of antimicrobial peptides. METHODS: The first author conducted a computer-based retrieval of PubMed, Springeriink, Web of Science. ScienceDirect databases for articles regarding the antimicrobial mechanism and research advance published from January 2013 to March 2019. RESULTS AND CONCLUSION: Antimicrobial peptides are a class of special molecules with broad-spectrum antimicrobial activity. In some organisms, antimicrobial peptides arc considered lo bo an important part of innate immune system. The antimicrobial mechanism of antimicrobial peptides can be divided into two main modes: direct killing and immune regulation, and direct killing mechanism can be further divided into membrane targeting and non-membrane targeting. At the same time, based on the extensive application of antimicrobial peptides, it is expected that many resistance strategies have been developed in microbial environments such as staphylococcus, oral bacteria (including streptococcus) and intestinal bacteria (including salmonella). These resistance strategies mainly include passive resistance and induction or adaptive resistance mechanisms. In the future research and application, cationic peptide is an effective choice to solve the increasing multidrug resistance. In addition to the obligation to design new methods to combat the resistance of antimicrobial peptides in bacteria, general preventive measures against the resistance of conventional antibiotics should also be paid attention to.
ABSTRACT
Pro-rich antimicrobial peptides are a group of linear peptides isolated from animals. These peptides have antibacterial activities and play an important role in innate immunity. Pro-rich antimicrobial peptides are devided into two classes:Pro-rich antimicrobial peptides from mammals and Pro-rich antimicrobial peptides from insects and other invertebrates.Members of Pro-rich antimicrobial peptides are all characterised by a high content of proline residues and predominantly active against Gram-negative bacterial species which they kill by a non-lytic mechanism,at variance with the majority of the known antimicrobial peptides. Evidence is accumulating that the Pro-rich peptides enter the cells without membrane lysis and,once in the cytoplasm,bind to,and inhibit the activity of DnaK protein that is essential to bacterial growth,thereby causing responsive bacteria death. This mode of action makes these peptides suitable for drug development efforts. As one of the best characterized Pro-rich peptides,PR-39 plays an important role in a number of biological processes. It has been found that PR-39 can induce the syndecan expression in mesenchymal cells, inhibit the NADPH oxidase activity of neutrophils and block the degradation of 1?B? and HIF-1?. These findings show that PR-39 can provide novel means in the control of inflammation, wound repair, ischemia-reperfusion injury,and angiogenesis for therapeutic purposes.