Figure 3.

Endocannabinoid system (ECS) interactions with barrier, immune, and microbiome systems. The ECS can alter the barrier function of the epithelium by increasing insertion of tight junction (TJ) proteins to enhance the physical barrier of the epithelium. Endocannabinoids also decrease chloride secretion to control the secretory barrier. The ECS, primarily through activation of CB₂ receptors, regulate immune cell function by decreasing cytokine release. There are reciprocal interactions between the ECS and the microbiome. By affecting each of these systems, the ECS therefore also regulates the complex crosstalk that exists between the epithelium and the immune system, the immune system and the microbiome, and the microbiome and the epithelium. Figure created with BioRender.com.