Ketoacids during hemodialysis

Rationale: End-stage renal disease patients on hemodialysis (HD) generally show a rapid decline in muscle mass and strength. Hemodialysis itself is considered an important cause of this decline in nutritional status, as it removes small-sized nutrients, such as amino acids (AAs), from the circulation. Previously, we have shown that the continuous removal of AAs during HD results in significantly decrease plasma AAs concentrations, which increase muscle proteolysis. In addition, we have shown that ingestion of 40 g protein during HD is able to compensate for AA removal. However, due to early satiety and the high nitrogen and phosphate content of protein, this strategy is not feasible for all hemodialysis patients. We have previously shown that ingestion of ketoanalogues of AAs (ketoacids), which do not contain nitrogen or phosphate, increases muscle protein synthesis rates. Currently it is, to our knowledge, not know if ketoacid ingestion during HD could support muscle maintenance.
Objective: To assess whether co-ingesting keto-analogues of branched-chain AAs along with protein during HD can attenuate HD-initiated muscle catabolism.
Study design: Randomized cross-over (two treatments) design.
Study population: 12 chronic HD patients
Intervention: During two HD sessions, included patients will ingest sips of (1) a protein beverage and (2) a protein and ketoacid beverage. Throughout the HD session, arterial and venous plasma samples and breath samples will be obtained at regular intervals. In addition, spent dialysate will be collected continuously throughout the hemodialysis session.
Main study parameters/endpoints: The primary endpoint in this study will be the net AA balance over the forearm, calculated by subtracting the venous from arterial AA concentrations. Secondary study parameters include plasma and breath L-(ring-13C6)-phenylalanine enrichments and AA concentrations in spent dialysate.

Co-ingesting keto-analogues of branched-chain AAs along with protein during HD attenuates HD-initiated muscle catabolism.

Samples will be taken every 30 min throughout 2 hemodialysis sessions

During two HD sessions, included patients will ingest sips of (1) a protein beverage and (2) a protein and ketoacid beverage. Throughout the HD session, arterial and venous plasma samples and breath samples will be obtained at regular intervals. In addition, spent dialysate will be collected continuously throughout the hemodialysis session.