Fig. 8.

D3-5 cell wall-derived LTA activates TLR2-p38 MAPK signaling and suppresses NF-κB signaling. a–f D3-5 and its cell wall-derived LTA feeding significantly decreased mRNA expression of pro-inflammatory genes like IL-6, IL-1ββ and TNF-α in the colon of normal B6 (C57BL/6J) mice (a–c), while these effects are abolished in the TLR2 KO mouse colons (d–f). g Western blot analyses show that D3-5 and its cell wall-derived LTA increased abundance of phospho-p38-MAPK, and decreased NF-κB, with no changes in p38-MAPK, Phospho-JNK, and JNK in the colons of older mice and B6 young mice. Such effects disappeared in TLR2 KO mice. Values are mean of n = 5–8 mice per group ± SEM (error bars). Values with *p < 0.05, **p < 0.001 are statistically significant. ns not significant