Intestinal hyperpermeability: The intestinal lining becomes more permeable than normal either via epithelial cell damage and or widening of the intercellular junctions
The intestinal epithelial lining functions
Absorb nutrients
Prevent the uptake of toxic compounds, pathogens and undigested food particles from the lumen to the circulation
Results in:
Increased absorption of large molecules (eg antigens, undigestd food particles, toxins) into the intestinal lmphatics initiating increased immune activation and absorption into the blood which increases toxic burden.
Local and systemic diseases
Decrease in absorption of small molecules
Detoxify xenobiotics
The mucosal barrier integrity is maintained by:
rapid turnover of epithelial cells
Maintenance of tight junctions
Peristalsis - removal of microbes
Hydrochloric acid and pancreatic enzymes which destroy infective microbes
Secretion of fluids such as mucus from epithelial crypt to wash away microbes by preventing adherance
Immunological mechanisms eg: IgA which bind foreign antigens