Scanning electron microscopy studies of erythrocytes in spinocerebellar degeneration

Clinical and genetic study of a family with spinocerebellar ataxia type 1 (SCA1) and beta-thalassemia

We report a family affected by autosomal dominant ataxia, in which numerous members also showed microcytosis. Genetic analysis demonstrated a CAG expansion in the SCA1 locus in five members, while all subjects with microcytosis revealed a C-T substitution at codon 39 of the beta-globin gene. A pure cerebellar syndrome with prominent gait ataxia characterized the first stages of the neurological disease. The fully developed disease included additional clinical findings such as dysarthria and dysphagia, and instrumental signs of axonal involvement of the peripheral nerves. Ophthalmoplegia was not observed. The coexistence of hereditary spinocerebellar degeneration and erythropathies or hemoglobinopathies has been previously described. We discuss the possible linkages between these two pathologies.

Blood from healthy animals and humans contains nondiscocytic erythrocytes

Blood samples (three drops) from healthy animals and humans were fixed in a 2.5% solution of glutaraldehyde in 0.1 M cacodylate buffer at pH 7.4 within seconds of being drawn. Dehydrated and gold-coated preparations were photographed at x 600 in a scanning electron microscope, then printed at x 1200. Erythrocytes were classified according to their shape and surface features into six classes, namely, normal red cells, flat cells, cells with surface changes, early cup forms, late cup forms, cells with altered margins. The size of each shape-determined class was expressed as a percentage of the total number of cells counted. Data relating to 23 healthy females and to a mouse, rat, rabbit and horse are reported. Although the presence of nondiscocytic erythrocytes in peripheral human blood has been described, the presence of similar cells in animal blood has not been reported previously.

Electron spin resonance studies of erythrocyte membrane in spinocerebellar degeneration

Erythrocyte membrane fluidity was examined by electron spin resonance spectra using nitroxide fatty acid spin labels in spinocerebellar degeneration (SCD). Subjects with SCD, motor neuron disease (MND) and controls did not differ in fluidity of the deep site (hydrophobic region) of the erythrocyte membrane. However, the fluidity of the shallow site (hydrophilic region) in the erythrocyte membrane was significantly less fluid in SCD than in controls and MND (outer hyperfine splitting of 5-nitroxide stearic acid: SCD 54.70 +/- 0.43 G, controls 53.57 +/- 0.41 G, MND 53.54 +/- 0.35 G, P less than 0.001). Serum HDL-cholesterol and membrane fluidity correlated significantly in controls, but not in SCD. A significant negative correlation between age and membrane fluidity was found in SCD, but not in controls. These data suggest that membrane abnormality exists in SCD and may be concerned with aging.