HPMCAS-Coated Alginate Microparticles Loaded with Ctx(Ile²¹)-Ha as a Promising Antimicrobial Agent against Salmonella Enteritidis in a Chicken Infection Model

Abstract

Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) in poultry is most often transmitted by the fecal− oral route, which can be attributed to high population density. Upon encountering the innate immune response in a host, the pathogen triggers a stress response and virulence factors to help it survive in the host. The aim of this study was to evaluate the effect of hypromellose acetate/succinate (HPMCAS)-coated alginate microparticles containing the Ctx(Ile 21 )-Ha antimicrobial peptide (AMP) on both intestinal colonization and systemic infection of laying hens challenged with S. Enteritidis. The applied AMP microsystem reduced the bacterial load of S. Enteritidis in the liver, with a statistical significance between groups A (control, no Ctx(Ile 21 )-Ha peptide) and B (2.5 mg of Ctx(Ile 21 )-Ha/kg) at 2 days postinfection (dpi), potentially indicating the effectiveness of Ctx(Ile 21 )-Ha in the first stage of infection by S. Enteritidis. In addition, the results showed a significant decrease in the S. Enteritidis counts in the spleen and cecal content at 5 dpi; remarkably, no S. Enteritidis counts were observed in livers at 5, 7, and 14 dpi, regardless of the Ctx(Ile 21 )-Ha dosage (p-value <0.0001). Using the Chi-square test, the effect of AMP microparticles on S. Enteritidis fecal excretion was also evaluated, and a significantly lower bacterial excretion was observed over 21 days in groups B and C, in comparison with the untreated control (p-value <0.05). In summary, the use of HPMCAS-Ctx(Ile 21 )-Ha peptide microcapsules in laying hens drastically reduced the systemic infection of S. Enteritidis, mainly in the liver, indicating a potential for application as a feed additive against this pathogen.

In Vitro Skin Co-Delivery and Antibacterial Properties of Chitosan-Based Microparticles Containing Ascorbic Acid and Nicotinamide

“…The absorbances were obtained at 600 nm at different times (0, 1, 6, 24, 48 h). MIC values were obtained with the same procedure but at higher concentrations (1000–4 mg/mL) according to Roque-Borda et al [ 19 ].…”

Antimicrobial Peptides as an Alternative for the Eradication of Bacterial Biofilms of Multi-Drug Resistant Bacteria

“…The first AMPs discovered and studied were based on structures related to defensins since these molecules were produced innately when some pathogenic agent came into contact with organisms [ 4 ]. AMPs are capable of modulating the immune system and generating a better response to defend the host since previous studies would indicate this potential as a single molecule [ 62 , 63 , 64 ], or in combination with another drugs, causing an even more beneficial and less toxic synergistic effect [ 65 , 66 ].…”

Beta‐lactam resistance and the effectiveness of antimicrobial peptides against KPC‐producing bacteria

“…Likewise, it was shown that alginate microparticles coated with hydroxymethylcellulose derivatives loaded with AMP can decrease hemolytic activity and increase bioavailability (Roque‐Borda et al, 2021). As well as allowing AMP permeability through the intestinal barrier and preventing systemic infection using a chicken infection model (Roque‐Borda et al, 2022).…”