New Insight into Vitamins E and K1 as Anti-Quorum-Sensing Agents against Pseudomonas aeruginosae

Today, antivirulence compounds that attenuate bacterial pathogenicity and have no interference with bacterial viability or growth are introduced as the next generation of antibacterial agents. However, the development of such compounds that can be used by humans is restricted by various factors, including the need for extensive economic investments, the inability of many molecules to penetrate the membrane of Gram-negative bacteria, and unfavorable pharmacological properties and cytotoxicity. Here, we take a new and different look into two frequent supplements, vitamin E and K-1, as anti-quorum-sensing agents against Pseudomonas aeruginosa, a pathogen that is hazardous to human life and responsible for several diseases. Both vitamins showed significant anti-biofilm activity (62% and 40.3% reduction by vitamin E and K-1, respectively), and the expression of virulence factors, including pyocyanin, pyoverdine, and protease, was significantly inhibited, especially in the presence of vitamin E. Cotreatment of constructed biofilms with these vitamins plus tobramycin significantly reduced the number of bacterial cells sheltered inside the impermeable matrix (71.6% and 69% by a combination of tobramycin and vitamin E or K-1, respectively). The in silico studies, besides the similarities of chemical structures, reinforce the possibility that both vitamins act through inhibition of the PqsR protein. This is the first report of the antivirulence and antipathogenic activity of vitamin E and K-1 against P. aeruginosa and confirms their potential for further research against other multidrug-resistant bacteria.

Automated summary

Vitamin E and K-1 exhibit significant anti-biofilm activity and effectively inhibit the expression of virulence factors in Pseudomonas aeruginosa. The combination of these vitamins with tobramycin reduces the number of bacteria sheltered inside biofilms. This study suggests the potential use of these vitamins as antivirulence agents against multidrug-resistant bacteria.