GFAP and diabetes mellitus: At the 8th week of the course of diabetes, compared with the control group, the expression of PGP9.5 (P < 0.01, Fig. 5A、C and Additional file 1: Fig. S1D) and GFAP (P < 0.01, Fig. 5B, D and Additional file 1: Fig. S1E) in the myenteric plexus of the colon were decreased, and the sizes of neurons and glial cells were smaller (Fig. 5A–D).