臨床泌尿器科69巻1号

2015年01月発行

特集 LOH症候群診療—最近の進歩

テストステロンと骨・筋肉

著者： 柳瀬敏彦¹ 村瀨邦崇¹ 永石綾子¹ 田邉真紀人¹ 野見山崇¹

所属機関： ¹福岡大学医学部内分泌・糖尿病内科

ページ範囲：P.46 - P.52

要旨　加齢性筋萎縮症（サルコペニア）および骨粗鬆症は種々の要因によって起こるが，テストステロン（T）の欠乏もその一因であり，LOH症候群の重要な病態と認識されている。内因性Tの低下により筋蛋白分解系が亢進し，筋蛋白同化が障害され，Tはこれらの機序を代償する。一方，TはARを介して，直接，骨組織に働くと同時に，各種サイトカインや成長因子を介して間接的に働き，骨形成と骨吸収を調節している。Tの骨作用にはエストロゲンへの転換を介した効果も含まれる。事実，Tの投与は性腺機能低下症におけるサルコペニアや骨粗鬆症の改善につながることが知られている。一方，T投与は，前立腺刺激作用を伴うため，Tの有益作用のみを保持した選択的アンドロゲン受容体修飾剤（SARM）も開発されている。現段階では臨床研究の範疇であるが，健常高齢男性や癌に伴うカヘキシア患者において，SARMの筋量増加，筋力向上に対する有効性が報告されている。

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