Sutipornpalangkul Werasak, Morales Noppawan Phumala, Unchern Supeenun, Sanvarinda Yupin, Chantharaksri Udom, Fucharoen Suthat
Department of Orthopaedic Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
J Med Assoc Thai. 2012 Jan;95(1):29-36.
Beta-thalassemia/Hemoglobin E (beta-thal/Hb E) is prevalent in Thailand. The imbalance of globin chains in red blood cells is the primary cause of this anemic disease. The excess alpha-globin in beta-thal/Hb E causes typical damage(s) to membrane of erythroblasts and erythrocytes. By using three paramagnetic labeled compounds (5-, 12-, and 16-spin labeled stearic acids, SLS), the changes of the molecular motion in the lipid bilayer of thalassemic RBCs that have structural modification can be detected.
to investigate erythrocyte membrane fluidity and the effect of vitamin E treatment in beta-thalassemia/Hemoglobin E patients by using spin labeling techniques.
The erythrocyte membrane fluidity was investigated in nine splenectomized and five non-splenectomized beta-thalassemia/hemoglobin E (beta-thal/Hb E) patients using EPR spin labeling techniques. To determine the effect of vitamin E on erythrocyte membrane fluidity, only the splenectomized patients were enrolled. Patients were divided into two groups. The first group received 350 mg vitamin E daily for a period of 1 month (n = 5) and the second group received placebo for an equal period (n = 4). Three paramagnetic fatty acid, 5-, 12-, and 16-doxyl stearic acids, (5-, 12- and 16-DS) were used to label phospholipids layer near both the surface (5-DS) and the deeper hydrophobic region of membrane (12-and 16-DS). Lipid peroxidation (TBARs) was measured using a colorimetric method. Vitamin E was measured with high performance liquid chromatography (HPLC).
Significantly higher values of erythrocyte membrane fluidity were revealed with 12-, 16-DS in splenectomized patients, as compared with non-splenectomized patients and normal subjects. In 3-thal/Hb E patients, fluidity values, both outer hyperfine splitting (2T(//)) and order parameter (S) of 12-DS showed inverse correlation with serum TBARs. There was no significant difference between the fluidity values measured with 5-DS. After vitamin E supplementation, the erythrocyte membrane fluidity was decreased in almost all patients. In contrast to the vitamin E supplementation group, increased erythrocyte membrane fluidity was demonstrated in the placebo group. Vitamin E supplementation also had effect on other clinical parameters such as increased plasma vitamin E, decreased serum TBARs and no change in hemoglobin.
The present results suggested the abnormal motion of lipid in the deeper phospholipids region of membrane. In addition, vitamin E supplementation may have a role in the prevention of erythrocyte membrane damage of these patients.
β地中海贫血/血红蛋白E（β-地贫/Hb E）在泰国较为常见。红细胞中珠蛋白链的失衡是这种贫血疾病的主要原因。β-地贫/Hb E中过量的α珠蛋白会对成红细胞和红细胞膜造成典型损伤。通过使用三种顺磁性标记化合物（5-、12-和16-自旋标记硬脂酸，SLS），可以检测到具有结构修饰的地中海贫血红细胞脂质双层中分子运动的变化。
通过自旋标记技术研究β地中海贫血/血红蛋白E患者的红细胞膜流动性及维生素E治疗的效果。
使用电子顺磁共振（EPR）自旋标记技术，对9例脾切除和5例未脾切除的β地中海贫血/血红蛋白E（β-地贫/Hb E）患者的红细胞膜流动性进行了研究。为了确定维生素E对红细胞膜流动性的影响，仅纳入了脾切除患者。患者分为两组。第一组每天服用350毫克维生素E，为期1个月（n = 5），第二组在相同时间段内服用安慰剂（n = 4）。使用三种顺磁性脂肪酸，即5-、12-和16-二氧硬脂酸（5-、12-和16-DS）来标记膜表面附近（5-DS）和膜较深疏水区域（12-和16-DS）的磷脂层。采用比色法测量脂质过氧化（TBARs）。用高效液相色谱法（HPLC）测定维生素E。
与未脾切除患者和正常受试者相比，脾切除患者中12-、16-DS显示出红细胞膜流动性值显著更高。在β-地贫/Hb E患者中，12-DS的流动性值，即外部超精细分裂（2T(//)）和序参数（S）均与血清TBARs呈负相关。用5-DS测量的流动性值之间无显著差异。补充维生素E后，几乎所有患者的红细胞膜流动性均降低。与补充维生素E组相反，安慰剂组的红细胞膜流动性增加。补充维生素E对其他临床参数也有影响，如血浆维生素E增加、血清TBARs降低且血红蛋白无变化。
目前的结果表明膜较深磷脂区域中脂质运动异常。此外，补充维生素E可能对预防这些患者的红细胞膜损伤有作用。
