Regarding chronic inflammation, lipopolysaccharides from gram-negative bacteria can cross the intestinal barrier and trigger systemic inflammation via the Toll-like receptor-4 pathway, promoting the production of pro-inflammatory cytokines (such as IL-1, IL-6, and TNF-α) and contributing to insulin resistance (Cani et al., 2009; Lee et al., 2020). This evidence concerns the gene TLR4 and Insulin resistance.