Promising Anti-Biofilm Agents and Phagocytes Enhancers for the Treatment of Candida albicans Biofilm–Associated Infections

Abstract

Little is known about the interactions among phagocytes and antifungal agents and the antifungal immunomodulatory activities on Candida species biofilms. Here, inhibition of C. albicans biofilms and the interactions among biofilms and phagocytes alone or in combination with essential oils, biological, and chemical agents, or fluconazole were investigated. Biofilm formation by a panel of 28 C. albicans clinical isolates from hospitalized patients, birds, and cattle was tested. The anti-biofilm activities of cinnamon and clove oils, sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and Enterococcus faecalis cell-free supernatant (CFS) in comparison with fluconazole were investigated using crystal violet and XTT reduction assays, expression of hypha-specific and hyphal regulator genes, and scanning electron microscopy (SEM) analysis. Of the tested C. albicans isolates, 15 of 28 (53.6%) were biofilm producers. Cinnamon followed by E. faecalis–CFS, SDS, and CTAB was the most effective inhibitors of planktonic C. albicans and biofilms. Fluconazole was an ineffective inhibitor of C. albicans biofilms. Sessile minimal inhibitory concentration (SMIC50) of cinnamon, SDS, CTAB, and E. faecalis–CFS downregulated the hypha-specific and regulator genes, albeit to various extents, when compared with untreated biofilms (P < 0.001). SEM analysis revealed disruption and deformity of three-dimensional structures in cinnamon oil–treated biofilms. C. albicans sessile cells within biofilm were less susceptible to phagocytosis than planktonic cells. The additive effects of phagocytes and the tested antifungals enabled phagocytes to engulf C. albicans cells rapidly in cinnamon, E. faecalis–CFS, or SDS-treated biofilms. No differences in anti-Candida or anti-biofilm eradication activities were detected among the tested isolates. Our findings reinforce the substantial anti-biofilm activity of cinnamon oil, SDS, and E. faecalis–CFS and provide new avenues for the development of novel anti-biofilm immunotherapies or antifungals that could be used prior to or during the management of cases with biofilm-associated infections.

Biofilm Formation and Phospholipase and Proteinase Production in Cryptococcus neoformans Clinical Isolates and Susceptibility towards Some Bioactive Natural Products

“…In addition, the MBEC values of natural products and antifungals were up to 8 times and 4 times higher than their MFC values, respectively. Tese results showed that the bioflm was more resistant to antimicrobial agents than planktonic cells, and this could be explained by the limited difusion of antimicrobial agents through the bioflm matrix or the lower growth rate of cells in the bioflm [6,36]. Tese results corroborated those reported earlier [14,24].…”

Antibiotic resistance: The challenges and some emerging strategies for tackling a global menace

“… 34 Agreeably, there is scientific research on the interactions of antibiotics such as synergy, additivity, indifference, and antagonism, but not much is known about the interactions of antibiotics with the innate immune components. 35 , 36 …”

“…34 Agreeably, there is scientific research on the interactions of antibiotics such as synergy, additivity, indifference, and antagonism, but not much is known about the interactions of antibiotics with the innate immune components. 35,36 Although the direct in vitro mechanism of action of an antibiotic is thought to be the driving force behind its antimicrobial efficacy, additional antibiotic effects on bacteria have been linked to better host immunological activities and immune optimization. 37 This includes the ability of antibiotics to affect virulence factors and other immune mechanisms that can modulate host response.…”

“…There are reports that innate endogenous host defense peptides have antimicrobial modes of action comparable to peptide antimicrobials given to patients such as daptomycin and colistin, and have evolved to protect the host by preventing pathogenic organisms from establishing infection 34 . Agreeably, there is scientific research on the interactions of antibiotics such as synergy, additivity, indifference, and antagonism, but not much is known about the interactions of antibiotics with the innate immune components 35,36 …”

Bioactive metabolites of Streptomyces misakiensis display broad-spectrum antimicrobial activity against multidrug-resistant bacteria and fungi

“…AMR has been a major concern because of the dramatic increase and huge challenge to the effective treatment of serious infections that are resistant to available antibiotics (Economou and Gousia, 2015). Additionally, the overuse/abuse of antibiotics in humans and food animals has resulted in the global dissemination of multidrug-resistant (MDR) bacteria and resistance genes, which are recently considered emerging contaminants for the environment (Abd El-Aziz et al, 2021;Ma et al, 2021;Saber et al, 2022;Xu et al, 2022). Moreover, the dissemination of MDR bacteria to human and animal food is facilitated by the application of animal manure in agriculture (Zalewska et al, 2021).…”