title: Circulating 20S proteasome is independently associated with abdominal muscle mass in hemodialysis patients.
abstract: Protein-energy wasting is highly prevalent in hemodialysis patients, and it contributes to patient morbidity and mortality. The ubiquitin-proteasome system is the major pathway for intracellular protein degradation and it is involved in the regulation of basic cellular processes. However, the role of this system in the determination of nutritional status is largely unknown. To examine a relationship between protein-energy wasting and the ubiquitin-proteasome system, a cross-sectional study of 76 hemodialysis patients was performed. Plasma concentrations of 20S proteasome were studied to evaluate its association with muscle and fat mass, which were investigated by abdominal muscle and fat areas measured using computed tomography and by creatinine production estimated using the creatinine kinetic model. Plasma 20S proteasome concentrations significantly and negatively correlated with abdominal muscle areas and creatinine production (rho = -0.263, P < 0.05 and rho = -0.241, P < 0.05, respectively), but not abdominal subcutaneous and visceral fat areas. Multiple regression analyses showed that 20S proteasome was a significant independent predictor of abdominal muscle area (P < 0.05). In conclusion, plasma 20S proteasome concentrations were independently associated with abdominal muscle mass in hemodialysis patients. Our findings indicate a relationship between circulating 20S proteasomes and muscle metabolism in these patients.
  
  
  BACKGROUND
  UMIN Clinical Trials Registry UMIN000012341.
authors: Renal Division, Department of Internal Medicine, Iwata City Hospital, Iwata, Shizuoka, Japan.
authors: Hirotaka
authors: H
authors: Fukasawa
authors: Renal Division, Department of Internal Medicine, Iwata City Hospital, Iwata, Shizuoka, Japan.
authors: Mai
authors: M
authors: Kaneko
authors: Renal Division, Department of Internal Medicine, Iwata City Hospital, Iwata, Shizuoka, Japan.
authors: Hiroki
authors: H
authors: Niwa
authors: Renal Division, Department of Internal Medicine, Iwata City Hospital, Iwata, Shizuoka, Japan.
authors: Takashi
authors: T
authors: Matsuyama
authors: First Department of Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan.
authors: Hideo
authors: H
authors: Yasuda
authors: The Department of Clinical Nutrition, School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka, Shizuoka, Japan.
authors: Hiromichi
authors: H
authors: Kumagai
authors: Renal Division, Department of Internal Medicine, Iwata City Hospital, Iwata, Shizuoka, Japan.
authors: Ryuichi
authors: R
authors: Furuya
mesh_terms: D000009:Abdominal Muscles / Q000473:pathology*; D000368:Aged; D003404:Creatinine / Q000378:metabolism; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000473:pathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D046988:Proteasome Endopeptidase Complex / Q000097:blood*; D006435:Renal Dialysis; D019282:Wasting Syndrome / Q000473:pathology*
chemical_list: D003404:Creatinine; D046988:Proteasome Endopeptidase Complex