| Abstract [eng] |
The human gut is a dynamic barrier that plays an important role in the absorption of essential nutrients, water, electrolytes and vitamins. Increased intestinal barrier permeability dysfunction is associated with various autoimmune, inflammatory and atopic diseases. Disorders of electrolyte absorption may be at the root of important diseases, and in vitro models made from human intestinal cells may contribute to a better understanding of the mechanisms involved in electrolyte absorption processes. The aim of this work was to develop an in vitro model that replicates the intestinal barrier function using a human intestinal epithelial cell line and to apply it to electrolyte absorption studies. To achieve this goal, the following tasks were set: 1) to select suitable conditions for in vitro barrier formation from intestinal epithelial cells on membrane culture inserts; 2) to evaluate the properties of the barrier formed under the selected conditions according to the number of gap junctions and the size of the transepithelial resistance; 3) to investigate the influence of electrolytes on the metabolic activity of HCEC-1CT cells; 4) to determine the concentration of electrolyte solutions induced by cells over time; 5) to evaluate the absorption of electrolytes through the intestinal epithelium by measuring the concentrations of electrolytes entering and crossing the barrier. First, the electrolyte concentrations in the solutions were determined during the study and the influence of electrolytes on the metabolic activity of HCEC-1CT cells was evaluated. A new model of the human intestinal barrier has been developed in vitro to study the reabsorption of electrolytes through the intestinal epithelium. Human colon epithelial cells (HCEC-1CT) were grown on permeable membrane culture inserts, which helped create a gut barrier system consisting of two compartments, the inner and outer, thus mimicking the intestinal lumen and circulatory system. After the formation of the intestinal model, the transepithelial electrical resistance was evaluated, which shows the formed tight and fractured connections that ensure the integrity of the barrier. Applying the developed intestinal model to in vitro electrolyte reabsorption studies, it was found that the K+, Ca2+, Mg2+, Na+ ions in the solutions are transported from the intestinal lumen into the bloodstream according to the concentration gradient, but at higher electrolytes concentrations, ion reabsorption against the concentration gradient occurred when the electrochemical potential was formed. |
