title: The effects of high-dose vitamin E supplementation on biomarkers of kidney injury, inflammation, and oxidative stress in patients with diabetic nephropathy: A randomized, double-blind, placebo-controlled trial.
abstract: Limited data are available that evaluated the effects of high-dose vitamin E supplementation on biomarkers of kidney injury, inflammation, and oxidative stress in patients with diabetic nephropathy (DN).
  
  
  
  This study was conducted to evaluate the effects of high-dose vitamin E supplementation on biomarkers of kidney injury, inflammation, and oxidative stress in patients with DN.
  
  
  
  This randomized double-blind placebo-controlled clinical trial was carried out among 60 patients with DN. Patients were randomly allocated into two groups to take either 1200 IU/d of vitamin E supplements (n = 30) or placebo (n = 30) for 12 weeks. Fasting blood samples were obtained at the onset of the study and after 12-week intervention to assess biomarkers of kidney injury, inflammation, and oxidative stress.
  
  
  
  After 12 weeks of intervention, compared with the placebo, vitamin E supplementation resulted in a significant increase in serum vitamin E levels (+42.3 ± 13.4 vs -0.8 ± 0.8 nmol/mL, P < .001) and a significant decrease in urine protein (-6.8 ± 4.3 vs -1.0 ± 8.0 mg/dL, P = .001) and protein-to-creatinine ratio (-0.2 ± 0.1 vs 0.0 ± 0.1, P < .001). In addition, a significant reduction in serum tumor necrosis factor-α (-35.4 ± 34.9 vs +5.6 ± 6.2 ng/L, P < .001), matrix metalloproteinase-2 (-556.7 ± 485.9 vs +60.4 ± 53.7 ng/mL, P < .001), matrix metalloproteinase-9 (-1461.5 ± 1456.0 vs +225.7 ± 488.2 ng/L, P < .001), malondialdehyde (-0.9 ± 0.5 vs +0.3 ± 0.4 μmol/L, P < .001), advanced glycation end products (-1832.2 ± 1941.6 vs +177.3 ± 324.1 arbitrary unit, P < .001), and insulin concentrations (-0.5 ± 2.7 vs +0.7 ± 1.0 μIU/mL, P = .03) was seen after the administration of vitamin E supplements compared with the placebo. Supplementation with vitamin E had no significant effects on other biomarkers of kidney injury, fasting plasma glucose, and insulin resistance compared with the placebo.
  
  
  
  Overall, our study demonstrated that oral high-dose vitamin E supplementation for 12 weeks among DN patients had favorable effects on biomarkers of kidney injury, inflammation, and oxidative stress.
authors: Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran.
authors: Parisa Golriz
authors: PG
authors: Khatami
authors: Department of Internal Medicine, Kashan University of Medical Sciences, Kashan, Iran.
authors: Alireza
authors: A
authors: Soleimani
authors: Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran.
authors: Nasrin
authors: N
authors: Sharifi
authors: Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran. Electronic address: aghadavod_m@yahoo.com.
authors: Esmat
authors: E
authors: Aghadavod
authors: Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran. Electronic address: asemi_r@yahoo.com.
authors: Zatollah
authors: Z
authors: Asemi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D003928:Diabetic Nephropathies / Q000150:complications / Q000378:metabolism*; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D007668:Kidney / Q000187:drug effects* / Q000293:injuries; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D010919:Placebos; D014810:Vitamin E / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D015415:Biomarkers; D010919:Placebos; D014810:Vitamin E
keywords: Diabetic nephropathy; Inflammation; Oxidative stress; Vitamin E; supplementation