シミズ　ユウコ   Shimizu Yuuko   清水　優子    所属   医学部 医学科（東京女子医科大学病院）    職種   教授
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Energetic characteristics of the new transthyretin variant A25T may explain its atypical central nervous system pathology.
掲載誌名	正式名：Laboratory investigation; a journal of technical methods and pathology 略　 称：Lab Invest ISSNコード：00236837/00236837
掲載区分	国外
巻・号・頁	83(3),pp.409-17
著者・共著者	Sekijima Yoshiki, Hammarström Per, Matsumura Miyuki, Shimizu Yuko, Iwata Makoto, Tokuda Takahiko, Ikeda Shu-Ichi, Kelly Jeffery W
発行年月	2003/03
概要	Transthyretin (TTR) is a tetrameric protein that must misfold to form amyloid fibrils. Misfolding includes rate-limiting tetramer dissociation, followed by fast tertiary structural changes that enable aggregation. Amyloidogenesis of wild-type (WT) TTR causes a late-onset cardiac disease called senile systemic amyloidosis. The aggregation of one of > 80 TTR variants leads to familial amyloidosis encompassing a collection of disorders characterized by peripheral neuropathy and/or cardiomyopathy. Prominent central nervous system (CNS) impairment is rare in TTR amyloidosis. Herein, we identify a new A25T TTR variant in a Japanese patient who presented with CNS amyloidosis at age 42 and peripheral neuropathy at age 44. The A25T variant is the most destabilized and fastest dissociating TTR tetramer published to date, yet, surprising, disease onset is in the fifth decade. Quantification of A25T TTR in the serum of this heterozygote reveals low levels relative to WT, suggesting that protein concentration influences disease phenotype. Another recently characterized TTR CNS variant (D18G TTR) exhibits strictly analogous characteristics, suggesting that instability coupled with low serum concentrations is the signature of CNS pathology and protects against early-onset systemic amyloidosis. The low A25T serum concentration may be explained either by impaired secretion from the liver or by increased clearance, both scenarios consistent with A25T's low kinetic and thermodynamic stability. Liver transplantation is the only known treatment for familial amyloid polyneuropathy. This is a form of gene therapy that removes the variant protein from serum preventing systemic amyloidosis. Unfortunately, the choroid plexus would have to be resected to remove A25T from the CSF-the source of the CNS TTR amyloid. Herein we demonstrate that small-molecule tetramer stabilizers represent an attractive therapeutic strategy to inhibit A25T misfolding and CNS amyloidosis. Specifically, 2-[(3,5-dich
DOI	10.1097/01.lab.0000059937.11023.1f
PMID	12649341