Knocking down Pseudomonas aeruginosa virulence by oral hypoglycemic metformin nano emulsion

Abstract

Long-term antibiotic treatment results in the spread of multi-drug resistance in Pseudomonas aeruginosa that complicates treatment. Anti-virulence agents can be viewed as alternative options that cripple virulence factors of the bacteria to facilitate their elimination by the host immunity. The use of nanoparticles in the inhibition of P. aeruginosa virulence factors is a promising strategy. This study aims to study the effect of metformin (MET), metformin nano emulsions (MET-NEs), silver metformin nano emulsions (Ag-MET-NEs) and silver nanoparticles (AgNPs) on P. aeruginosa virulence factors’ expression. The phenotypic results showed that MET-NEs had the highest virulence inhibitory activity. However, concerning RT-PCR results, all tested agents significantly decreased the expression of quorum sensing regulatory genes of P. aeruginosa; lasR, lasI, pqsA, fliC, exoS and pslA, with Ag-MET-NEs being the most potent one, however, it failed to protect mice from P. aeruginosa pathogenesis. MET-NEs showed the highest protective activity against pseudomonal infection in vivo. Our findings support the promising use of nano formulations particularly Ag-MET-NEs as an alternative against multidrug resistant pseudomonal infections via inhibition of virulence factors and quorum sensing gene expression.

Combination of Meropenem and Zinc Oxide Nanoparticles; Antimicrobial Synergism, Exaggerated Antibiofilm Activity, and Efficient Therapeutic Strategy against Bacterial Keratitis

“…Biofilm formation is regulated at the molecular level through a package of biofilm genes ( lasR , fliC , and pslA ) [ 43 ], a reduction in biofilm density is associated with diminished expression of biofilm genes [ 44 , 45 ], and the quantification results of the expression of biofilm genes ( lasR , fliC , and pslA ) showed a significant decrease in expression. Taken together, the mixture of meropenem and ZnO-NPs downregulates biofilm gene expression, which provides reasonable explanation for the reduced biofilm density.…”

GC-MS Analysis and Microbiological Evaluation of Caraway Essential Oil as a Virulence Attenuating Agent against Pseudomonas aeruginosa

“…P. aeruginosa ATCC 27853 overnight cultures in MHB with and without 1% v / v of caraway oil were centrifuged to isolate the supernatants. An amount of 500 μL of supernatants was incubated with 1 mL skimmed milk (1.25%) for 1 h at 37 °C according to [ 65 ]. The decrease in optical density of skimmed milk due to protease activity was estimated at 600 nm.…”