Hirayama Satoshi, Miida Takashi, Obayashi Konen, Yamazaki Fusako, Yamazaki-Sakurai Miho, Ito Masayuki, Saito Yuji, Hanyu Osamu, Suzuki Katsunori, Aizawa Yoshifusa
Division of Endocrinology and Metabolism, Department of Homeostatic Regulation and Developments, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi 1-757, Niigata City, Niigata 951-8510, Japan.
Clin Chim Acta. 2005 Jun;356(1-2):110-6. doi: 10.1016/j.cccn.2005.01.004. Epub 2005 Mar 23.
The majority of the lipoprotein in cerebrospinal fluid (CSF) is apolipoprotein E (apoE)-containing HDL. Since neuronal cells express lipoprotein receptors which recognize apoE, apoE in CSF-HDL is believed to be important for the development of central nervous system (CNS) in children. In adults, the apoE phenotype affects the plasma apoE concentration and the epsilon 4 allele is a risk factor for Alzheimer's disease. Due to the requirement for CNS development, we examined whether the apoE phenotype affects the composition and concentration of CSF-HDL in children.
We determined the apoE phenotype in 107 neurologically normal subjects, including 67 children (<20 years), by isoelectronic focusing. We also measured apoE, total cholesterol (TC), and phospholipid (PL) concentrations in the CSF.
The respective frequencies of apoE4/3, E3/3 and E3/2 were 16.4%, 77.6%, and 6.0%. The allele frequencies of epsilon 4, epsilon 3, and epsilon 2 were 0.082, 0.888, and 0.030, respectively. There were no significant differences in the CSF-apoE, TC, or PL concentrations or the apoE/PL ratio among the apoE phenotypes. However, the CSF-apoE/PL ratio was significantly higher in children than in adults.
The apoE phenotype does not affect the composition or concentration of CSF-HDL in children. We speculate that an apoE4 carrier is prevented in childhood from the impaired development of central nervous system by CSF-HDL enriched with apoE.
