Evaluation of Antibacterial Activity of Proteins and Peptides Using a Specific Animal Model for Wound Healing

Abstract

Wound healing is a complex process involving the integrated actions of numerous cell types, soluble mediators, and extracellular matrix (ECM). In this study, phospholipase A(2) (PLA(2)) purified from crotalid snake venom was found to express in vitro bactericidal activity against a group of clinical human pathogens. Based on the sequence homology of PLA(2), a series of peptides were derived from the C-terminal region of crotalid PLA(2). These short synthetic peptides were found to reproduce the bactericidal activity of its parent molecule. In vitro assays for bactericidal and cytolytic activities of these peptides showed very high microbicidal potency against Gram-negative and Gram-positive (Staphylococcus aureus) bacteria. Variants of the peptides showed reduced toxicity toward normal human cells, while retaining high bactericidal potency. Here we describe the protocol for evaluating the wound healing process by antibacterial peptides. We evaluated the biological roles of the candidate peptides in skin wound healing, using a specific BALB/c mice model. Peptide-treated animals showed accelerated healing of full-thickness skin wounds, with increased reepithelialization, collagen synthesis, and angiogenesis observed during the healing process. Healing wounds in protein/peptide-treated mice had higher densities of neutrophils, macrophages, and fibrocytes. Along with increased leukocyte infiltration, levels of macrophage-derived chemokine expression were also upregulated. These results demonstrate that the protein/peptide derived from snake venoms promotes healing of skin wounds. The primary mechanism seems to be an increase in leukocyte infiltration, leading to locally elevated synthesis and release of collagen and growth factors.

A new method of wound treatment: targeted therapy of skin wounds with reactive oxygen species-responsive nanoparticles containing SDF-1α

“…17 Briefly, animals were anesthetized by intraperitoneally injected amobarbital at 40 mg/kg. The back skin was shaved and disinfected with 75% ethanol, and then a piece of 8 mm diameter skin was removed with 8 mm punch biopsy together with subcutaneous tissues.…”

Discovery of Distinctin-Like-Peptide-PH (DLP-PH) From the Skin Secretion of Phyllomedusa hypochondrialis, a Prototype of a Novel Family of Antimicrobial Peptide

“…In this second context, antimicrobial peptides (AMPs) have attracted the attention of many researchers because of their numerous unique advantages, such as potent effects against a variety of pathogens, including many superbugs, their ability to suppress biofilm formation (Reffuveille et al, 2014 ; Pletzer and Hancock, 2016 ), and that their apparent primary mechanism of action (degradation of the microbial membrane) might prove to be more resistant to the development of antibiotic resistance. Moreover, in addition to their direct antimicrobial activities, AMPs have been recently discovered to possess beneficial, secondary actions such as mediating the immune response and enhancing both wound healing and angiogenesis (Samy et al, 2011 ; Habets and Brockhurst, 2012 ).…”