Effects of ascorbic acid deficiency on protein and lipid oxidation in livers from SMP30/GNL knockout mice.
Ascorbic acid (AA) functions as an electron donor and scavenges reactive oxygen species such as superoxide, singlet oxygen, and hydroxyl radicals in vitro. However, little is known about the effect of an AA deficiency on protein and lipid oxidation levels in the liver. Therefore, we measured the levels of protein carbonyl and thiobarbituric acid reactive substances (TBARS) in livers from senescence marker protein-30 (SMP30)/gluconolactonase (GNL) knockout (KO) mice. These mice are deficient in AA, because they lack the SMP30/GNL gene, which is essential for the biosynthesis of AA in vivo. To track the effect of an AA deficiency, at 30 d of age, mice were divided into the following four groups: AA (-) SMP30/GNL KO, AA (+) SMP30/GNL KO, AA (-) wild type (WT), and AA (+) WT. The AA (+) groups were given water containing 1.5 g/L AA, whereas the AA (-) groups received water without AA for 57 d. All mice were fed an AA-free diet. Subsequently, protein carbonyl levels in livers from AA (-) SMP30/GNL KO mice were significantly higher than those from the other three groups; however, TBARS levels were not significantly different among the four groups. Therefore, AA must act as an anti-oxidant for proteins but might not directly protect lipid oxidation in the liver.
Molecular Regulation of Aging, Tokyo Metropolitan Institute of Gerontology.
Akiko
A
Amano
Yasunori
Y
Sato
Yuki
Y
Kishimoto
Keita
K
Takahashi
Setsuko
S
Handa
Toshiro
T
Aigaki
Naoki
N
Maruyama
Akihito
A
Ishigami
D000818:Animals; D001205:Ascorbic Acid / Q000008:administration & dosage; D001206:Ascorbic Acid Deficiency / Q000378:metabolism*; D004195:Disease Models, Animal; D050356:Lipid Metabolism / Q000502:physiology*; D008099:Liver / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D010084:Oxidation-Reduction; D050050:Protein Carbonylation / Q000502:physiology; D011506:Proteins / Q000378:metabolism*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D011506:Proteins; D017392:Thiobarbituric Acid Reactive Substances; D001205:Ascorbic Acid