腫瘍死滅因子 (TNF) は,リバース電子輸送によって結核における病原性ミトコンドリアROSを誘発する
Francisco J Roca1, Laura J Whitworth1,2, Hiran A Prag3
1Molecular Immunity Unit, Cambridge Institute of Therapeutic Immunology and Infectious Diseases, Department of Medicine, University of Cambridge, Cambridge CB2 0AW, UK.
まとめ
過剰な腫瘍死因 (TNF) は,ミトコンドリアの活性酸素種 (mROS) を増加させ,結核の感受性を誘発する. コンプレックスI阻害剤であるメトホルミンは,mROSとマクロファージの死滅を阻害し,結核の治療の可能性を示唆する.
科学分野:
- 免疫学
- 細胞生物学
- 生物化学
背景:
- 結核 (TB) は世界的な健康問題です.
- 腫瘍死因 (TNF) は結核において2つの役割を果たし,耐性因子と感受性の媒介者として作用する.
- 過剰なTNFは病原性マクロファージの死滅を引き起こし,結核を悪化させる可能性があります.
研究 の 目的:
- Mycobacterium tuberculosisに感染したマクロファージにおけるTNF誘発によるミトコンドリアの活性酸素種 (mROS) 生成のメカニズムを解明する.
- 結核におけるメトホルミンの潜在的治療作用を調査する.
主な方法:
- ゼブラフィッシュとヒトのマクロファージモデルを使用しました
- mROS生成におけるミトコンドリア複合体Iによる逆電子伝送 (RET) の役割を調査した.
- TNFとメトホルミンの細胞のグルタミン吸収,サクシネート濃度,およびmROS産生への影響を評価した.
主要な成果:
- 感染したマクロファージの過剰なTNFは,複合体IでRET経由でmROSを増加させる.
- TNF誘発によるグルタミン吸収は,複合体IでRETと超酸化物生成を誘発するサクシネートを上昇させます.
- コンプレックスI阻害剤であるメトフォーミンは,TNF誘発のmROSとマクロファージの死滅を,ゼブラフィッシュとヒトの両方の細胞で取り消した.
結論:
- TNF誘発のmROS生成は,ミトコンドリア複合体Iにおけるサクシネート誘発のRETによって媒介される.
- メトフォーミンはこの経路を効果的に阻害し,病原性マクロファージの死滅を防ぐ.
- メトフォーミンは結核に対する宿主指向の治療法として有望である.
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