Oxidative Stress Involvement in Antibacterial Therapy

Antimicrobial therapy is necessary to reduce the global burden of disease and infection. Oxidative stress (OS) may play a key function in determining the extent of efficacy of antimicrobial treatment regimens. However, whether the agent has a ‘static’ (inhibitory) or ‘cidal’ (killing) effect or the ability to induce an oxidative state, achieving therapy is a complex one. Bactericidal agents are known to induce a downstream cascade of responses in bacteria beyond their direct target(s). These responses correspond with the generation of reactive oxygen species (ROS) and the development of OS that eventually results in the disruption/destruction of integral components and/or processes within bacteria cells. In contrast, bacteriostatic antibiotics may not always induce cell death. Both classes of antimicrobials are useful in antibacterial therapy. The actualization of an oxidatively stressed microbial cell is key to optimizing the available antibiotic therapy options for efficient treatment and reducing the acquisition of microbial resistance. Studies are still required to expatiate on the role played by OS in antimicrobial therapy. This chapter, therefore, focuses on discussing available research data and knowledge on this complex role by OS, while highlighting potential future application and development prospects. In addition, the chapter touched OS and their sources, antimicrobial lethality-OS association, factors affecting OS-mediating therapy and efficacy, bacterial adaptations to OS in response to antimicrobial treatment and prospects for combination therapy with bactericidal agents and adjuvants.

Keywords: Oxidative stress, Reactive species, Antibiotics, Antimicrobial therapy, Bacteria, Adaptations.