Fig. 1

Effects of dietary vitamin D supplementation on high fat diet induced enteric neuronal loss and intestinal morphometric. Representative micrographs (a-c), morphometrics (d, g) and numbers of neurons in myenteric (MG) and submucosal (SG) ganglia (e, f, h, i) in ileum and colon from mice fed either normal diet (ND) or high fat diet (HFD) supplemented with different concentrations of vitamin D (0 to 20x normal concentration). a-c cryosections from ileum of ND 1x vitamin D concentration (a), HFD 1x vitamin D concentration (b) and HFD 20x vitamin D concentration (c) immunostained for HuC/HuD-biotin. Myenteric neurons are indicated with arrows and submucosal neurons with arrowheads. d, g No effect on intestinal morphology is observed in either ileum (d) or colon (g) in ND or HFD regardless of vitamin D concentration. e, f, h, i Numbers of neurons per mm in longitudinal cut sections of the intestine. Vitamin D supplementation (0-20x normal concentration) have no effect on neuronal survival in MG (e, h) and SG (f, i) of ileum (e, f) and colon (h, i) in ND fed mice. Vitamin D supplementation (0-2x normal concentration) had no effect on HFD induced neuronal loss in MG ileum (e) and colon (h) but high vitamin D supplementation (20x normal concentration) prevented the HFD-induced myenteric neuronal loss in ileum and colon. Bar represent 20μm