Current Advances in Lipid and Polymeric Antimicrobial Peptide Delivery Systems and Coatings for the Prevention and Treatment of Bacterial Infections

Abstract

Bacterial infections constitute a threat to public health as antibiotics are becoming less effective due to the emergence of antimicrobial resistant strains and biofilm and persister formation. Antimicrobial peptides (AMPs) are considered excellent alternatives to antibiotics; however, they suffer from limitations related to their peptidic nature and possible toxicity. The present review critically evaluates the chemical characteristics and antibacterial effects of lipid and polymeric AMP delivery systems and coatings that offer the promise of enhancing the efficacy of AMPs, reducing their limitations and prolonging their half-life. Unfortunately, the antibacterial activities of these systems and coatings have mainly been evaluated in vitro against planktonic bacteria in less biologically relevant conditions, with only some studies focusing on the antibiofilm activities of the formulated AMPs and on the antibacterial effects in animal models. Further improvements of lipid and polymeric AMP delivery systems and coatings may involve the functionalization of these systems to better target the infections and an analysis of the antibacterial activities in biologically relevant environments. Based on the available data we proposed which polymeric AMP delivery system or coatings could be profitable for the treatment of the different hard-to-treat infections, such as bloodstream infections and catheter- or implant-related infections.

Cecropin D-derived synthetic peptides in the fight against Candida albicans cell filamentation and biofilm formation

“…Strategies to reduce peptide toxicity include peptide further modification or encapsulation (van Gent et al, 2021). Combining them with conventional antifungal drugs is also a good approach, especially because the use of drug combinations can not only improve the efficiency of both antifungal agents, often with lowering their active concentration range and reducing their cytotoxic effect, but also can decrease the development of the resistance.…”

Tailored anti-biofilm activity – Liposomal delivery for mimic of small antimicrobial peptide

“…In this regard, the incorporation of 7e-SMAMP inside liposomes resulted in positive surface charge (Table 1), which can aid the penetration into the extracellular matrix of the biofilm, thus increasing the anti-biofilm capability of the payload [50]. Conventional liposomes have been shown to successfully improve cellular uptake [80]. Moreover, liposomes prepared with the phosphatidylcholine revealed optimal ability to enhance the anti-biofilm activity of chlorhexidine [21].…”

The future of recombinant host defense peptides

“…Some groups have also been working on the development of HDP delivery systems to have a time-controlled release to improve bioavailability and to minimize toxicity and proteolytic degradation and, in consequence, increase stability, when administered in vivo [ 58 ] . Most of these studies, however, have been done using synthetic HDPs.…”