Co-localization of the zinc transporter ZnT8 (slc30A8) with ghrelin and motilin in the gastrointestinal tract of pigs

Histol Histopathol. 2016 Feb;31(2):205-11. doi: 10.14670/HH-11-663. Epub 2015 Sep 21.

Abstract

Zinc is an important co-factor for insulin storage in pancreatic β-cells of different species and the uptake of this ion into insulin containing secretory vesicles is managed by the zinc transporter, ZnT8, a member of the slc30A gene family. Recent studies indicate that this protein is a major autoimmune target in human type 1A diabetes and has also been implicated by genome-wide association studies in type 2 diabetes. Since individuals suffering from type 1 diabetes often develop gastrointestinal motility disorders, we investigated the expression of ZnT8 in the porcine gastrointestinal tract. For this purpose, we studied the cell-type specific expression of ZnT8 in the gut and its co-expression with endocrine hormones that are closely linked to intestinal motility regulation. Nested RT-PCR and immunostaining of sequential serial sections, as well as double-immunostaining using antibodies directed against ZnT8, ghrelin, motilin, neurotensin, serotonin and glucagon-like peptide 1, indicated that ZnT8 is co-localized with ghrelin and motilin. Our findings provide important information about the cell-type specific expression of ZnT8 in the porcine gastrointestinal system. The selective and exclusive expression of ZnT8 in two endocrine cell-types that are engaged in motility functions may be of particular interest for further investigations into type I diabetes-associated gastrointestinal dysfunctions.

MeSH terms

  • Animals
  • Cation Transport Proteins / metabolism*
  • Diabetes Mellitus, Type 1 / immunology
  • Diabetes Mellitus, Type 2 / immunology
  • Disease Models, Animal
  • Endocrine System / metabolism
  • Gastric Mucosa / metabolism
  • Gastrointestinal Tract / metabolism*
  • Gene Expression Profiling
  • Gene Expression Regulation*
  • Ghrelin / metabolism*
  • Immunohistochemistry
  • Intestinal Mucosa / metabolism
  • Motilin / metabolism*
  • Real-Time Polymerase Chain Reaction
  • Swine

Substances

  • Cation Transport Proteins
  • Ghrelin
  • Motilin