beta-Amyloid precursor protein (beta APP) in human gut with special reference to the enteric nervous system.
The distribution of the beta-amyloid precursor protein (betaAPP) in the human gastrointestinal tract, from esophagus trough rectum, was studied using immunoblotting, as well as combined immunohistochemical and image analysis (optic microdensitometry) techniques. The study was focused on the enteric nervous system. betaAPP was detected by means of a monoclonal antibody (22C11), which recognizes all betaAPP isoforms as well as betaAPP-like proteins. Immunoblotting revealed two main protein bands, one corresponding to full-length betaAPPs (estimated molecular masses of approximately 97-115 kDa); the other corresponded to a protein with estimated molecular masses of 55 kDa. Specific betaAPP immunoreactivity (IR) was found in the submucous and myenteric plexuses localized in the supporting glial cells rather than in neurons. Differences were encountered neither in the localization nor in the intensity of immunostaining among different segments of the gastrointestinal tract. Moreover, no age-dependent changes were found. betaAPP IR was also regularly observed in blood vessels, primarily labelling endothelial cells. Our results provide evidence for the occurrence of betaAPP in human gastrointestinal tract of healthy people in both neuronal and nonneuronal tissues. Whether or not these findings have functional or clinical relevance remains to be clarified in future studies.
Cabal
A
A
Departamento de Morfología y Biología Celular, Facultad de Medicina, Universidad de Oviedo, Spain.
Alonso-Cortina
V
V
Gonzalez-Vazquez
L O
LO
Naves
F J
FJ
Del Valle
M E
ME
Vega
J A
JA
D000328:Adult; D000368:Aged; D016564:Amyloid beta-Protein Precursor / Q000032:analysis*; D000911:Antibodies, Monoclonal; D001808:Blood Vessels / Q000737:chemistry; D004064:Digestive System / Q000737:chemistry* / Q000294:innervation; D017615:Enteric Nervous System / Q000737:chemistry* / Q000166:cytology; D018604:Epitope Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D015151:Immunoblotting; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016900:Neurofilament Proteins / Q000032:analysis*; D009474:Neurons / Q000737:chemistry; D009418:S100 Proteins / Q000032:analysis*
D016564:Amyloid beta-Protein Precursor; D000911:Antibodies, Monoclonal; D016900:Neurofilament Proteins; D009418:S100 Proteins