Specifically, their research, involving DSS-induced colitis in mice and inflammatory THP-1 cells, revealed that L. johnsonii GLJ001 influences the levels of SCFAs, which are closely linked to macrophage polarization, by improving gut microbiota balance in colitis-affected mice (206) Furthermore, the use of SCFAs to intervene in an in vitro inflammatory macrophage model reduces inflammation and significantly decreases the levels of GPR41 and GPR43, which play a role in immune and inflammatory responses (206). The gene discussed is FFAR2; the disease is colitis.