Protective effect of pyruvate upon cultured mesothelial cells exposed to 2 mM hydrogen peroxide.

Rat peritoneal mesothelial cells in culture have the capability of generating hydrogen peroxide. Exposure of these cells to glucose-enriched, lactated-buffered fluids for peritoneal dialysis significantly increases the production of H(2)O(2). Increased liberation of oxygen radicals also involves the risk of damaging the peritoneal membrane.

High glucose induces a hypertrophic, senescent mesothelial cell phenotype after long in vivo exposure.

Previous studies, done using our mouse model for population analysis of the mesothelium, showed evidence indicating that in vivo, long-term exposure (up to 30 days) of the peritoneum to high-glucose (4.25% D-glucose) concentration dialysis solutions resulted in a hypertrophic mesothelial phenotype characterized by increased cell surface area, multinucleation, low proliferative capabilities, reduced cell viability, and enhanced enzymatic activity. These elements that define a senescent population of cells were not related to the pH of the fluid and its osmolality, or to the presence of buffer lactate.

Effect of hyperosmolality upon the mesothelial monolayer exposed in vivo and in situ to a mannitol-enriched dialysis solution.

Studies done using the in vivo mouse model of population analysis of mesothelium showed that dialysis solutions containing high concentrations of glucose induced the development of a hypertrophic phenotype. Since these changes were neither related to the low pH nor to the presence of lactate buffer, we hypothesized that the presence of glucose was at the origin of the observed alterations. Theoretical analysis of the problem points to three possible mechanisms: hyperosmolality; metabolic changes derived from the high-glucose concentration itself, and/or the presence of products derived from the nonenzymatic degradation of glucose.

Biocompatibility of a glucose-free, acidic lactated solution for peritoneal dialysis evaluated by population analysis of mesothelium.

Glucose-enriched, racemic lactate buffered solutions for peritoneal dialysis induce a significant reduction of cell viability as well as a hypertrophic, senescent phenotype of the exposed monolayer. The present study was designed to verify whether the aforementioned changes resulted form the buffer, from the osmotic agent, or from a combined effect of both. Mice were acutely (2 h) and long-term (15 and 30 days) exposed to daily intraperitoneal injections of a racemic lactate, heat-sterilized, low-pH (5.

Population analysis of mesothelium in situ and in vivo exposed to bicarbonate-buffered peritoneal dialysis fluid.

Population analysis of mesothelium (PAM) done using the in vivo and almost in situ technique of mesothelial cell imprints revealed that lactate-buffered solutions had detrimental effects upon cell viability, that high glucose concentration affected cytokinesis, whereas the association of both components led to a decreased density population of cells showing a larger surface area. In the present study, PAM was done on mesothelium of mice exposed to bicarbonate-buffered peritoneal dialysis fluid (BBF) with glucose concentrations of 1.5 and 4.