l-Arginine supplementation blunts resistance exercise improvement in rats with chronic kidney disease

Life Sci. 2019 Sep 1:232:116604. doi: 10.1016/j.lfs.2019.116604. Epub 2019 Jun 28.

Abstract

Chronic kidney disease (CKD) patients present L-arginine (L-arg) deficiency and L-arg supplementation has been used as a treatment. In addition, sarcopenia is another common problem in CKD population, resistance training (RT) is one of the conservative strategies developed to prevent CKD progression, and however there are no evidences of a combination of these two strategies to treat CKD outcomes. The aim of this study was to evaluate the effects of oral L-arg supplementation combined with RT in an experimental model of CKD. Twenty-five Munich-Wistar male rats, 8-week-old were divided in 5 groups: Sham (sedentary control), Nx (CKD sedentary), Nx L-arg (CKD sedentary supplemented with 2% of L-arg), Nx RT (CKD exercised) Nx RT + L-arg (CKD exercised and supplemented with 2% of L-arg). CKD model was obtained by a subtotal 5/6 nephrectomy. RT was performed on a ladder climbing, three weekly sessions on non-consecutive days, with an intensity of 70% maximum carrying capacity. They were submitted to RT and/or L-arg supplementation for 10 weeks. There was a significant improvement in muscle strength, renal function, anti-inflammatory cytokines, arginase metabolism and renal fibrosis after RT. However, the combination of RT and L-arg impaired all the improvements promoted by RT alone. The L-arg supplementation alone did not impair renal fibrosis and renal function. In conclusion, RT improved inflammatory balance, muscle strength, renal function and consequently decreased renal fibrosis. Nevertheless, the association with L-arg supplementation prevented all these effects promoted by RT.

Keywords: 5/6 nephrectomy; Amino acid supplementation; Inflammatory profile; Renal fibrosis; Resistance exercise.

MeSH terms

  • Animals
  • Arginine / metabolism
  • Arginine / pharmacology*
  • Cytokines / metabolism
  • Dietary Supplements
  • Disease Progression
  • Fibrosis / metabolism
  • Kidney / metabolism
  • Male
  • Muscle Strength / drug effects
  • Muscle, Skeletal / metabolism
  • Oxidative Stress / drug effects
  • Physical Conditioning, Animal / methods
  • Physical Conditioning, Animal / physiology*
  • Rats
  • Rats, Wistar
  • Renal Insufficiency, Chronic / diet therapy*
  • Renal Insufficiency, Chronic / metabolism
  • Resistance Training / methods

Substances

  • Cytokines
  • Arginine