METHYLGLYOXAL CONCENTRATION AND GLYOXALASE ACTIVITIES IN THE HUMAN LENS
METHYLGLYOXAL CONCENTRATION AND GLYOXALASE ACTIVITIES IN THE HUMAN LENS
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DOI：
10.1006/exer.1994.1135
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发表时间：
1994-10-01
影响因子：
3.4
通讯作者：
THORNALLEY, PJ
中科院分区：
文献类型：
--
作者：
HAIK, GM;LO, TWC;THORNALLEY, PJ
测定了26个人晶状体中乙二醛酶I和乙二醛酶II的活性和甲基乙二醛的浓度。乙二醛酶I的活性（平均+/-s.D）为15.62+/-3.90 U （g湿重）（-1），乙二醛酶II的活性为0.189+/-0.087 U （g湿重）（-1）（n = 26）。人晶状体甲基乙二醛浓度为1.78+/-0.84 nmol （g湿重）（-1）（n = 26）。乙二醛酶I和乙二醛酶II活性与受试者年龄呈显著负相关，甲基乙二醛浓度与受试者年龄无相关性。隐形眼镜中甲基乙二醛的浓度是正常人血液样本的20倍。鉴于先前报道的人类晶状体中还原型谷胱甘肽浓度随着年龄的增长而下降，预计乙醛酶I的原位活性会显著下降，并且随着年龄的增长，人类晶状体蛋白对甲基乙二醛修饰的易感性也会随之下降。甲基乙二醛的代谢和甲基乙二醛修饰蛋白的形成可能与老年性和糖尿病性白内障的发生有关。
The activities of glyoxalase I and glyoxalase II and the concentration of methylglyoxal were determined in 26 human lenses. The activity of glyoxalase I (mean+/-s.D.) was 15.62+/-3.90 U (g wet weight)(-1) and the activity of glyoxalase II was 0.189+/-0.087 U (g wet weight)(-1) (n = 26). The concentration of methylglyoxal of the human lenses was 1.78+/-0.84 nmol (g wet weight)(-1) (n = 26). There was a significant negative correlation of both the activity of glyoxalase I and the activity of glyoxalase II with subject age but no correlation of methylglyoxal concentration with subject age. The concentration of methylglyoxal in the lenses was similar to 20-fold higher than in blood samples from normal human subjects. Given the previously reported decrease in the concentration of reduced glutathione in the human lens with age, there is expected to be a marked decrease in in situ activity of glyoxalase I and concomitant susceptibility of human lens proteins to modification by methylglyoxal with age. The metabolism of methylglyoxal and the formation of methylglyoxal-modified proteins may be linked to the development of senile and diabetic cataract.