Postbiotics as potential new therapeutic agents for sepsis

Abstract

Sepsis is the main cause of death in critically ill patients and gut microbiota dysbiosis plays a crucial role in sepsis. On the one hand, sepsis leads to the destruction of gut microbiota and induces and aggravates terminal organ dysfunction. On the other hand, the activation of pathogenic gut flora and the reduction in beneficial microbial products increase the susceptibility of the host to sepsis. Although probiotics or fecal microbiota transplantation preserve gut barrier function on multiple levels, their efficacy in sepsis with intestinal microbiota disruptions remains uncertain. Postbiotics consist of inactivated microbial cells or cell components. They possess antimicrobial, immunomodulatory, antioxidant and antiproliferative activities. Microbiota-targeted therapy strategies, such as postbiotics, may reduce the incidence of sepsis and improve the prognosis of patients with sepsis by regulating gut microbial metabolites, improving intestinal barrier integrity and changing the composition of the gut microbiota. They offer a variety of mechanisms and might even be superior to more conventional 'biotics' such as probiotics and prebiotics. In this review, we present an overview of the concept of postbiotics and summarize what is currently known about postbiotics and their prospective utility in sepsis therapy. Overall, postbiotics show promise as a viable adjunctive therapy option for sepsis.

Keywords: Dysbiosis; Gut microbiota; Postbiotics; Sepsis.

Figure 1

Probiotics, prebiotics, synbiotics and postbiotics. Probiotics are live strains of bacteria or specific living components of the microbiota, while prebiotics are substances that can be digested by the microbiota. Synbiotics are a combination of prebiotics and probiotics that have been used together. (Created with BioRender.com)

Figure 2

Timeline illustrating the main published definitions of postbiotics

Figure 3

Postbiotics’ mechanism of action in sepsis. SCFA Short-chain fatty acids. (Created with BioRender.com)