スダ, タケオ Department of Nutrition, The University of Tokushima School of Medicine
アカマツ, アキラ Department of Internal Medicine, The Matsuyama Prefecture Hospital
中屋, 豊 Department of Nutrition, The University of Tokushima School of Medicine 徳島大学 教育研究者総覧 KAKEN研究者をさがす
マスダ, ヤスノブ R amp D Division of Q.P. Co.
デサキ, ジュンゾウ Department of Anatomy, The Ehime University School of Medicine
cholesterol acyltrasferase deficiency
Lecithin : cholesterol acyltrasferase (LCAT) plays a key role in the cholesterol metabolism-mediated esterification of free cholesterol into the cholesterol ester in normal plasma. Familial LCAT deficiency is frequently associated with anemia. Using biochemical and physiological techniques, the erythrocytes of this patient were investigated to gain an insight into the relationship between the abnormalities of lipid metabolism and erythrocyte membrane fragility. Abnormal erythrocytes, so-called Target cells and/or Knizocytes, were observed at 20% in our patient’s erythrocytes. Moreover, the mean corpuscular volume of the patient’s cells was 7% greater than that of a normal individual. In the membrane lipids of the patient’s erythrocytes, cholesterol and phosphatidylcholine increased, and phosphatidylethanolamine decreased. The electron spin resonance technique with a fatty acid spin probe showed that the membrane fluidity was more elevated than that of normal cells in spite of the increase in cholesterol content and the cholesterol/ phospholipid ratio of the membrane of patient’s erythrocytes. The patient’s abnormally shaped erythrocytes were less deformed than those of the normal individual under high shear stress. The partial depletion of membrane cholesterol from the patient’s erythrocytes was demonstrated by incubation with normal plasma with LCAT activity. The increment of transformed erythrocytes during the incubation could be prevented by cholesterol depletion from the patient’s erythrocyte membrane. These findings indicate that normochromic anemia of the patient might be caused by erythrocyte fragility resulting from decreased deformity and/or abnormal shape of the cells due to abnormal lipid composition in the membrane.
The journal of medical investigation : JMI
jmi_49_3-4_147.pdf 157 KB