| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1490-2 | ||||
Resumo:Nosocomial infections (NCI) affect a substantial number of patients worldwide, leading to increased mortality and financial impact on healthcare systems. Data from the National Institutes of Health and Centers for Disease Control and Prevention in the United States indicate that up to 80% of the total number of microbial infections and more than 60% of nosocomial infections are due to biofilms. Furthermore, approximately 60-70% of all INC are associated with some type of implanted medical device and can affect, in addition to the implant site, the mucous layer of the digestive and respiratory tracts. Biofilms are significant structures due to their ability to exhibit resistance to antibiotics and antifungals through their complex microbial structure, which increases inter- and intra-species exchange of resistance genes, ensures protection against antimicrobial penetration, and increases persistence. Microorganisms present in multispecies biofilms can exhibit antimicrobial resistance up to 1000 fold compared to their planktonic counterparts. The attachment of biofilms to biomaterial surfaces remains a significant challenge that substantially impairs their clinical applicability, limiting the advancement of these devices. Given the consequences and prevalence of biofilm-mediated INC, it is important to promote advancement in the treatment and development of new, more effective molecules that can contain INC, caused by increased resistance mechanisms. Bioactive peptides, such as host defense or antimicrobial peptides (PAMs), may emerge as an alternative due to their pharmacological versatility and desirable physicochemical profiles. AMPs have action against a wide range of pathogens, including bacteria, fungi, viruses, protozoa, as well as tumor cells. In this study, the peptide kyotorphin conjugated with ibuprofen, IbKTP-NH2, was evaluated for its ability to inhibit the growth of multispecies biofilms on polymeric and metallic materials. Antimicrobial susceptibility tests were carried out in liquid media, following CLSI guidelines against the fungus Candida albicans, and the bacteria Pseudomonas aeruginosa and Streptococcus pneumoniae. The inhibition of adhesion and formation of multispecies biofilms caused by exposure to IbKTP-NH2 was evaluated on polymeric material (toothbrush bristles) and Titanium alloys (orthodontic metal rods). Changes in biofilm morphology were evaluated by scanning electron microscopy (SEM). The minimum biofilm inhibitory concentrations (MBIC50) calculated for bacterial strains were between 46.5 to 1000 μM. SEM analyzes revealed significant disruption of biofilms, with inhibition of extracellular matrix production, effective reduction in the number of cells that make up the biofilm and changes in the morphology of treated cells, suggesting a possible synergistic and competitive interaction between P. aeruginosa and other microorganisms that form part of biofilms (C. albicans and S. pneumoniae). In conclusion, the results obtained suggest that the IbKTP-NH2 peptide significantly inhibits the growth of mixed biofilms in the analyzed materials. The significant antimicrobial and possible antivirulence properties make IbKTP-NH2 a good candidate for the study of new drugs for the prevention and control of nosocomial infections and eventually microorganisms from chronic wounds. Palavras-chave: biofilms, peptides, implantable materials, antimicrobials Agência de fomento:FAPESP e CAPES | |||||