Bakhti M, Habibi-Rezaei M, Moosavi-Movahedi A A, Khazaei M R
School of Biology, University College of Science, University of Tehran; Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran.
J Biochem. 2007 Jun;141(6):827-33. doi: 10.1093/jb/mvm096. Epub 2007 Apr 11.
Increased fructose concentration in erythrocytes of diabetic patients subject haemoglobin (Hb) to be glycated by fructose. Haemoglobin glycation results in early and advanced glycation end products which are known as HbA(1c) and Hb-AGE, respectively. In diabetics the Hb-AGE content raises and the mean parameter multiplication value (PMV) for Hb-AGE has been calculated at 6 against non-diabetics. We are emphasizing on fluorescence descriptive pairs especially of 370/440 nm (lambda(ex)/lambda(em)) and thioflavin T binding process to characterize short-term Hb-AGE formation upon glycation with fructose or fructation. Secondary structure elements were estimated after far-UV circular dichroism spectropolarimetery which reveals up to 11.3% beta-content attainment for 20 days incubated Hb with fructose which is concurred with enhanced hydrophobicity of the protein. The later is described through enhanced 1-anilino-8-naphthalene sulphonate (ANS) binding to fructated protein. The preventive effect of acetylsalicylic acid on glycation of methemoglobin and consequently, Hb-AGE formation also has been included.
糖尿病患者红细胞中果糖浓度升高会使血红蛋白(Hb)被果糖糖化。血红蛋白糖化会产生早期和晚期糖基化终产物,分别称为糖化血红蛋白A1c(HbA1c)和晚期糖基化终产物血红蛋白(Hb-AGE)。在糖尿病患者中,Hb-AGE含量升高,并且已计算出Hb-AGE的平均参数增殖值(PMV),糖尿病患者与非糖尿病患者的该值之比为6。我们着重研究荧光描述对,特别是370/440纳米(激发波长/发射波长)的荧光描述对以及硫黄素T结合过程,以表征果糖糖化或果糖化后短期Hb-AGE的形成。在远紫外圆二色光谱偏振法测定后估计二级结构元件,结果显示与果糖孵育20天的Hb的β含量达到11.3%,这与蛋白质疏水性增强一致。后者通过增强1-苯胺基-8-萘磺酸盐(ANS)与果糖化蛋白质的结合来描述。还包括乙酰水杨酸对高铁血红蛋白糖化以及由此导致的Hb-AGE形成的预防作用。