Exercise augments the acute anabolic effects of intradialytic parenteral nutrition in chronic hemodialysis patients

Abstract

Exercise augments the acute anabolic effects of intradialytic parenteral nutrition in chronic hemodialysis patients. Am J Physiol Endocrinol Metab 286: E589-E597, 2004. First published December 16, 2003 10.1152/ajpendo.00384.2003.-Decreased dietary protein intake and hemodialysis (HD)-associated protein catabolism are among several factors that predispose chronic hemodialysis (CHD) patients to uremic malnutrition and associated muscle wasting. Intradialytic parenteral nutrition (IDPN) acutely reverses the net negative whole body and forearm muscle protein balances observed during the HD procedure. Exercise has been shown to improve muscle protein homeostasis, especially if performed with adequately available intramuscular amino acids. We hypothesized that exercise performance would provide additive anabolic effects to the beneficial effects of IDPN. We studied six CHD patients at two separate HD sessions: 1) IDPN administration only and 2) IDPN ϩ exercise. Patients were studied 2 h before, during, and 2 h after an HD session by use of a primed constant infusion of L-[1-13 C]leucine and L-[ring-2 H5] phenylalanine. Exercise combined with IDPN promoted additive twofold increases in forearm muscle essential amino acid uptake (455 Ϯ 105 vs. 229 Ϯ 38 nmol⅐100 ml Ϫ1 ⅐min Ϫ1 , P Ͻ 0.05) and net muscle protein accretion (125 Ϯ 37 vs. 56 Ϯ 30 g⅐100 ml Ϫ1 ⅐min Ϫ1 , P Ͻ 0.05) during HD compared with IDPN alone. Measurements of whole body protein homeostasis and energy expenditure were not altered by exercise treatment. In conclusion, exercise in the presence of adequate nutritional supplementation has potential as a therapeutic intervention to blunt the loss of muscle mass in CHD patients. malnutrition; muscle; catabolism UREMIC MALNUTRITION and muscle wasting are highly prevalent and associated with unacceptably high rates of morbidity and mortality in chronic hemodialysis (CHD) patients (44). The causal factors for this wasting syndrome are multiple, including dialysis-related and non-dialysis-related events (12,14,18). Among these factors, decreased dietary intake, sedentary lifestyle, and hemodialysis (HD)-associated catabolism are important, because they can be either prevented and/or treated (15,16,23). We have recently shown that nutritional supplementation in the form of intradialytic parenteral nutrition (IDPN) can effectively compensate the catabolic effects of HD procedure by stimulating muscle protein synthesis, promoting a positive net skeletal muscle protein balance (17, 37).Although nutritional supplementation alone is effective in reversing uremic malnutrition to some extent, certain complementary interventions can be utilized to promote its anabolic actions. Exercise with increased amino acid availability has been demonstrated to facilitate muscle uptake of amino acids and muscle protein accretion in healthy subjects (25,26,42,49). Exercise directs more nutrients toward muscle tissues and induces a greater sensitivity and responsiveness to metabolic events regulated by insulin compared with nutrient admin...

Exercise improves albumin fractional synthetic rate in chronic hemodialysis patients

“…Analyses were conducted as part of a study from which data on whole body and muscle protein homeostasis have already been reported (Pupim et al, 2004b). Out of the six subjects previously recruited (Pupim et al, 2004b), five (46719 years old, four males, four blacks) had information on FSR available for analysis and were included in this study.…”

“…Out of the six subjects previously recruited (Pupim et al, 2004b), five (46719 years old, four males, four blacks) had information on FSR available for analysis and were included in this study. Inclusion criteria consisted of patients on a thrice-weekly CHD program for more than 6 months, using a biocompatible hemodialysis membrane (Fresenius F80) and an adequate dose of dialysis (single pool Kt/V41.4).…”

“…We have shown that intra-dialytic parenteral nutrition (IDPN) reverses hemodialysis (HD)-induced catabolism Pupim et al, 2002), including the fractional synthetic rate (FSR) of albumin (Pupim et al, 2004a), a direct estimate of acute changes in hepatic albumin synthesis (De Feo et al, 1991;Barazzoni et al, 1999;Ahlman et al, 2001). As the beneficial effects of IDPN on somatic protein stores are further augmented by the addition of exercise (Pupim et al, 2004b), we hypothesized that exercise performance combined with IDPN during a single HD treatment would lead to a more profound increase in albumin FSR compared to what is observed with IDPN alone. …”

“…As the beneficial effects of IDPN on somatic protein stores are further augmented by the addition of exercise (Pupim et al, 2004b), we hypothesized that exercise performance combined with IDPN during a single HD treatment would lead to a more profound increase in albumin FSR compared to what is observed with IDPN alone.…”

“…Patients with active infectious or inflammatory disease, liver failure of any cause, hospitalized within 3 months before the study, with recirculation in the vascular access and/or vascular access blood flow less than 750 ml/min detected on the arterioveous (AV) shunt, and those receiving steroids and/or immunosuppressive agents were excluded. Detailed design and methods, including IDPN administration and blood sampling can be found elsewhere (Pupim et al, 2004b).Within a week before each study patients were brought to the General Clinical Research Center to estimate the workload required to achieve their maximal heart rate, and to test www.nature.com/ejcn the subject's ability to sustain exercise at 40% of this level for 15 min (Wasserman, 1999). Heart rate and blood pressure were monitored while the patients pedaled on a recumbent stationary cycle (Ergonomics 800, Ergolin, Bandhagen, Sweden) with incremental ( þ 10 W/min) changes in workload until the maximal heart rate was attained.…”