title: 1H NMR spectroscopy analysis of metabolites in the kidneys provides new insight into pathophysiological mechanisms: applications for treatment with Cordyceps sinensis.
abstract: BACKGROUND
  The number of patients with chronic kidney disease (CKD) is continuously growing worldwide. Treatment with traditional Chinese medicine might slow the progression of CKD.
  
  
  METHODS
  In this study, we evaluated the renal protective effects of the Chinese herb Cordyceps sinensis in rats with 5/6 nephrectomy. Male Sprague-Dawley mice (weighing 150-200 g) were subjected to 5/6 nephrectomy. The rats were divided into three groups: (i) untreated nephrectomized group (OP group, n = 16), (ii) oral administration of C. sinensis-treated (4 mg/kg/day) nephrectomized group (CS group, n = 16) and (iii) sham-operated group (SO group, n = 16). The rats were sacrificed at 4 and 8 weeks after 5/6 nephrectomy, and the kidneys, serum and urine were collected for (1)H nuclear magnetic resonance spectral analysis. Multivariate statistical techniques and statistical metabolic correlation comparison analysis were performed to identify metabolic changes in aqueous kidney extracts between these groups.
  
  
  RESULTS
  Significant differences between these groups were discovered in the metabolic profiles of the biofluids and kidney extracts. Pathways including the citrate cycle, branched-chain amino acid metabolism and the metabolites that regulate permeate pressure were disturbed in the OP group compared to the SO group; in addition, these pathways were reversed by C. sinensis treatment. Biochemistry and electron microscopic images verified that C. sinensis has curative effects on chronic renal failure. These results were confirmed by metabonomics results.
  
  
  CONCLUSIONS
  Our study demonstrates that C. sinensis has potential curative effects on CKD, and our metabonomics results provided new insight into the mechanism of treatment of this traditional Chinese medicine.
authors.affiliation: Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Zhong
authors.forename: Xia
authors.initials: X
authors.lastname: Liu
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zhou
authors.forename: Xu
authors.initials: X
authors.lastname: Hao
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: Shanmai
authors.initials: S
authors.lastname: Guo
authors.forename: Weiming
authors.initials: W
authors.lastname: Wang
authors.forename: Donghai
authors.initials: D
authors.lastname: Lin
authors.forename: Nan
authors.initials: N
authors.lastname: Chen
mesh_terms: D000419:Albuminuria / Q000517:prevention & control; D000597:Amino Acids, Branched-Chain / Q000378:metabolism; D000818:Animals; D001806:Blood Urea Nitrogen; D032661:Cordyceps; D003404:Creatinine / Q000097:blood*; D004195:Disease Models, Animal; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage*; D007676:Kidney Failure, Chronic / Q000188:drug therapy* / Q000378:metabolism* / Q000517:prevention & control; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008516:Medicine, Chinese Traditional / Q000379:methods; D055432:Metabolomics / Q000379:methods; D015999:Multivariate Analysis; D009392:Nephrectomy / Q000379:methods; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D016896:Treatment Outcome
chemical_list: D000597:Amino Acids, Branched-Chain; D004365:Drugs, Chinese Herbal; D003404:Creatinine