Investigation of mexA expression in drug resistance pseudomonas aeruginosa treated by curcumin and antibiotic

Background and Purpose: Pseudomonas aeruginosa is a gram-negative opportunistic pathogen and is a common cause of nosocomial infections. Curcumin as an herbal drug has anti-inflammatory and anti-cancer properties that nowadays researcher survey its antibacterial function. Aim of the study was to investigate the anti-bacterial potential of curcumin, against clinical isolates of Pseudomonas aeruginosa in combination with ciprofloxacin.Materials and methods: herein, we isolated 45 clinical strains of Pseudomonas aeruginosa from patients in Guilan province. after antibiogram and MIC determination , 10 ciprofloxacin (CP) resistant isolates were treated by ciprofloxacin only and in the combination with nano-curcumin (nano-particle encapsulated curcumin). Antimicrobial activity of nano-curcumin was assessed by calculating the OD600 after 48h.Results: 22% of isolates were resistant to all antibiotics and the highest resistance for ciprofloxacin (CP) was determined in 1024 μg/ml. Our findings showed that a combined nano-curcumin and ciprofloxacin treatment reduced the bacterial counts below the lowest detectable limit after 48h. Also Q-RT-PCR analysis revealed that nano-curcumin can cause decrease of mexA expression, subsequently increase of ciprofloxacin efficiency in resistance isolates.Discussion: our results suggested that nano-curcumin could be inhibits bacterial growth through different mechanism such as mexA downregulation in combination with lower dose of ciprofloxacin (1/2 MIC).

Keywords:

Ciprofloxacin , mexA , Pseudomonas Aeruginosa , nano-Curcumin , MIC