The mRNA levels of TNF-α and IL-6 were examined in colonic tissue, and similarly, TNF-α and IL-6 mRNA levels were significantly higher in the IBS group than in the CON group, whereas the intervention of L. plantarum ZYC501, GOS, and synbiotics reduced the TNF-α and IL-6 mRNA levels (Figure 3I,J). Here, IL6 is linked to irritable bowel syndrome.