title: Comparison of the effects of nicotinic acid and nicotinamide degradation on plasma betaine and choline levels.
abstract: The present study was to compare the effects of nicotinic acid and nicotinamide on the plasma methyl donors, choline and betaine.
  
  
  
  Thirty adult subjects were randomly divided into three groups of equal size, and orally received purified water (C group), nicotinic acid (300 mg, NA group) or nicotinamide (300 mg, NM group). Plasma nicotinamide, N1-methylnicotinamide, homocysteine, betaine and choline levels before and 1.5-h and 3-h post-dosing, plasma normetanephrine and metanephrine concentrations at 3-h post-dosing, and the urinary excretion of N1-methyl-2-pyridone-5-carboxamide during the test period were examined.
  
  
  
  The level of 3-h plasma nicotinamide, N1-methylnicotinamide, homocysteine, the urinary excretion of N1-methyl-2-pyridone-5-carboxamide and pulse pressure (PP) in the NM group was 221%, 3972%, 61%, 1728% and 21.2% higher than that of the control group (P < 0.01, except homocysteine and PP P < 0.05), while the 3-h plasma betaine, normetanephrine and metanephrine level in the NM group was 24.4%, 9.4% and 11.7% lower (P < 0.05, except betaine P < 0.01), without significant difference in choline levels. Similar but less pronounced changes were observed in the NA group, with a lower level of 3-h plasma N1-methylnicotinamide (1.90 ± 0.20 μmol/l vs. 3.62 ± 0.27 μmol/l, P < 0.01) and homocysteine (12.85 ± 1.39 μmol/l vs. 18.08 ± 1.02 μmol/l, P < 0.05) but a higher level of betaine (27.44 ± 0.71 μmol/l vs. 23.52 ± 0.61 μmol/l, P < 0.05) than that of the NM group.
  
  
  
  The degradation of nicotinamide consumes more betaine than that of nicotinic acid at identical doses. This difference should be taken into consideration in niacin fortification.
authors: Institute of Basic Medical Sciences, Medical College, Dalian University, Dalian 116622, China; Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki 444-8787, Japan.
authors: Wu-Ping
authors: WP
authors: Sun
authors: Institute of Science and Technology Austria, Am Campus 1, Klosterneuburg 3400, Austria.
authors: Ming-Zhu
authors: MZ
authors: Zhai
authors: Institute of Basic Medical Sciences, Medical College, Dalian University, Dalian 116622, China; Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang 110004, China.
authors: Da
authors: D
authors: Li
authors: Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki 444-8787, Japan.
authors: Yiming
authors: Y
authors: Zhou
authors: Institute of Basic Medical Sciences, Medical College, Dalian University, Dalian 116622, China.
authors: Na-Na
authors: NN
authors: Chen
authors: College of Environmental and Chemical Engineering, Dalian University, Dalian 116622, China.
authors: Ming
authors: M
authors: Guo
authors: Institute of Basic Medical Sciences, Medical College, Dalian University, Dalian 116622, China. Electronic address: elevensun@126.com.
authors: Shi-Sheng
authors: SS
authors: Zhou
mesh_terms: D000328:Adult; D001622:Betaine / Q000097:blood* / Q000378:metabolism; D001794:Blood Pressure; D002794:Choline / Q000097:blood* / Q000378:metabolism; D019587:Dietary Supplements / Q000009:adverse effects; D005527:Food, Fortified / Q000009:adverse effects; D006710:Homocysteine / Q000097:blood / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007700:Kinetics; D008297:Male; D008676:Metanephrine / Q000097:blood / Q000378:metabolism; D008745:Methylation; D009525:Niacin / Q000009:adverse effects / Q000378:metabolism*; D009536:Niacinamide / Q000009:adverse effects / Q000378:metabolism*; D009647:Normetanephrine / Q000097:blood / Q000378:metabolism; D011728:Pyridones / Q000097:blood / Q000378:metabolism / Q000652:urine; D011897:Random Allocation; D055815:Young Adult
chemical_list: C525085:N-methyl-2-pyridone-5-carboxamide; D011728:Pyridones; D009647:Normetanephrine; D006710:Homocysteine; D009536:Niacinamide; D009525:Niacin; D001622:Betaine; D008676:Metanephrine; D002794:Choline
keywords: Betaine; Choline; Homocysteine; Methylation; Nicotinamide; Nicotinic acid