The control of muscle protein turnover in patients on peritoneal dialys

Wasting is observed in a large percentage of patients receiving peritoneal dialysis (PD) and it is associated with functional impairment and worse outcome. In this article, we review the current state of our knowledge regarding the effects of PD on protein metabolism and their possible interactions with the uremia-induced and comorbidity-induced alterations in protein metabolism. Available evidence shows that glucose-based PD induces a new state in muscle protein dynamics, which is characterized by decreased turnover rates and a reduced efficiency of protein turnover, a condition which may be harmful in stress conditions, when nutrient intake is diminished or during superimposed catabolic illnesses. The effects of PD on protein turnover may overlap with the effects of aging and comorbidities to promote net catabolism. There is a need to develop more effective treatments to enhance the nutritional and functional status of PD patients. New approaches include the use of icodextrins to maintain extracellular volume, amino acids/keto acids-containing supplements combined with physical exercise, vitamin D, myostatin antagonism, and ghrelin agonism for malnourished patients refractory to standard nutritional therapy.