- 著者
-
Toshifumi Nanjo
Takaomi Fukuhara
Naoko Kameshima
Daijiro Yanagisawa
Shino Shimizu
Takeshi Shimizu
Akihiko Shiino
Hiroyasu Akatsu
Takayuki Yamamoto
Ikuo Tooyama
- 出版者
- Japan Brain Science society
- 雑誌
- 脳科学誌 (ISSN:13415301)
- 巻号頁・発行日
- vol.42, pp.5-20, 2013-09-30 (Released:2017-06-01)
Previous studies reported that β-amyloid peptides (Aβ) were observed in nasal mucosa of postmortem human samples. In the model mouse of Alzheimer's disease (AD), nasal Aβ levels positively correlate with insoluble Aβ levels in the brain. However, it is difficult to measure Aβ content in human nasal smears. Here we have reported a novel and sensitive method of measuring Aβ42 content in the human nasal cavity. We collected nasal smears by cotton swab from the mucosa of the inferior nasal concha and common nasal meatus of 13 normal volunteers with an age range of 30-78 years. The swabs were put into microtubes and the protein content extracted with 700 μL of 80% formic acid. Ten microliters of the extract solution was removed from each sample to assay protein levels. The remaining 690 μL was incubated at 70℃ for one hour, transferred to a centrifugal filter device, and centrifuged for one hour at 14000 g to remove larger protein complexes and cellular debris. The filtrates were concentrated to 20 μL, and then neutralized by adding 480 μL of 1 M Tris. Finally, the Aβ42 protein concentrations were measured using a commercially available ELISA kit, with the samples from five volunteers assayed for Aβ42 content without pretreatment. Our novel method for collecting and assaying nasal mucosal smears enabled us to measure Aβ42 content in both the inferior nasal concha and the common nasal meatus of all cases examined here, despite the levels being under detection limits (0.5 pmol/L) without pretreatment. The mean levels of Aβ42 per total protein in the inferior nasal concha and common nasal meatus of normal controls were 6.24 ± 3.70 fmol/g and 2.10 ± 0.77 fmol/g, respectively. Thus, there was significantly more Aβ42 content per total protein in the inferior nasal concha than in the common nasal meatus (P<0.01). Thus, this method would be useful for AD screening.