#2490 Analyzing the morphology of mesothelial cells when exposed to peritoneal dialysis solutions

Abstract Background and Aims Glucose remains the predominant osmotic agent in peritoneal dialysis (PD), yet its prolonged use is associated with an inevitable decline in peritoneal filtration capacity. Persistent contact with glucose during dialysis can induce significant morphological and functional changes in the peritoneum. In this study, we explore the morphological alterations in mesothelial cells exposed to both conventional glucose-based PD solutions and an innovative biocompatible PD solution (XyloCore) containing L-carnitine and Xylitol. Method Met5A mesothelial cells were seeded and cultured on a polyester filter (with a pore size of 0.4 micrometers, Transwell, 12 well type, Millipore) utilizing a full medium. The impact of PD solutions, differentiating between glucose-based and XyloCore, was assessed on cells cultivated on transwells. These cells were exposed to PD solutions on the apical side and to culture medium on the basal side. The cells were then employed for proteomic and metabolomic assessments and were also fixed and scrutinized through scanning electron microscopy (SEM). Results Through unsupervised hierarchical clustering analysis, discernable proteomic distinctions emerged between wild-type (WT) cells (control) and cells exposed to either glucose-based PD solution or XyloCore. In SEM analysis, control cells exhibited a distinct flat epithelial appearance. Contrastingly, subjecting WT cells to treatment with a glucose-based PD solution induced significant alterations in cellular morphology. Notably, cells displayed elongated shapes, loosening of cell-cell contacts, and a consistent denuding of the culture surface. In contrast, XyloCore maintained a better cellular morphology and mitigated cell detachment. Conclusion Preserving the integrity of the mesothelial barrier is crucial for maintaining peritoneal ultrafiltration capacity. The findings suggest that glucose-based PD solutions trigger early morphological changes in cell shape and cell-cell contacts, likely stemming from alterations in cytoskeleton or adhesion molecules. The exploration of new osmotic agents in clinical practice holds paramount significance for the future of peritoneal dialysis.