Similarly, in the HF→HFB group, mRNA expression of Muc2 was increased (Figure 5B), which is the secreted mucin responsible for protection of the epithelial barrier [57]; however, there was no difference between dietary groups in mRNA expression of the epithelial-associated mucins Muc1 and Muc3. Further, regenerating islet-derived protein-3γ (Reg3γ), which reduces microbial–host interactions at mucosal surfaces [58,59,60], was increased only in the HF→HFB group compared to the HF and HF→LF groups (Figure 5B). Here, MUC5AC is linked to hydrops fetalis.