Structure and binding properties of serum albumin in uremic patients at different periods of hemodialysis

Few diagnostic methods are available that describe uremia related changes of the albumin molecule structure in hemodialysis patients. The impaired human serum albumin (HSA) function is an essential part of the uremic syndrome and probably influences the long-term outcome of patients on maintenance dialysis. The albumin binding capacity (characterized for different binding centers on the molecule) is one of the relevant clinical parameters. During the current study, marker substances were utilized to evaluate center-specific binding capacity. Patients were divided into 3 groups depending on the time on hemodialysis (HD) treatment (in years) with healthy blood donors as control. Compared to healthy persons, results demonstrate a considerable impairment of binding characteristics in HD patients. Only in patients on maintenance HD for more than 5 years did ligand binding properties improve significantly. A correlation between the time of chronic HD and the recovery in binding capacity was found for the majority of binding centers of the HSA molecule. Similar results were seen applying such analytical methods as thermography (melting points) and thermofluorescence. Binding capacity impairment found for specified binding centers on the HSA molecule as the main serum carrier protein may have a direct impact on different clinical situations and the HD long-term outcome.