Synergistic activity of chlorhexidine and synoeca-MP peptide against Pseudomonas aeruginosa.

‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬This study aims to evaluate the in vitro antimicrobial and immunomodulatory activities and cytotoxicity of chlorhexidine (CHX) and synoeca-MP peptide alone or in combination against Pseudomonas aeruginosa. The antimicrobial property was evaluated by the determination of minimal inhibitory concentration， minimum bactericidal concentration， and planktonic bacteria and biofilm inhibition. Immunomodulatory activity was determined by enzyme-linked immunosorbent assay and nitric oxide production by the Griess reaction method. According to the results， synoeca-MP combined with CHX demonstrated antimicrobial effectiveness compared with its isolated use， in addition to immunomodulatory activity (upregulating MPC-1 and tumor necrosis factor-α and downregulating nitric oxide and interleukin-10). In this context， it is expected that the substances， together， could be capable of controlling bacterial infection and dissemination， besides potentiating macrophages' immune response against the studied microorganism. Moreover， reducing the CHX concentration by the addition of synoeca-MP peptide may， in a beneficial way， minimize the undesirable effects of both， CHX and synoeca-MP in a clinical setting.