鎘是環境中常見的污染物質，透過ROS的產生使細胞遭受氧化逆境進而導致細胞死亡。Metallothionein (MT)與glutathione (GSH) 是解除細胞內鎘毒性的主要生物分子。鎘會與thioredoxin (Trx)的活性中心結合，抑制Trx活性進而影響細胞死亡路徑。為了要探討鎘如何影響MT基因、GSH與Trx三者之間的相互關係，我們將HEK293細胞處理鎘，發現γ-glutamylcysteine synthetase (γ-GCS )表現量降低並且伴隨細胞內GSH消耗。鎘誘導MT基因大量表現，造成Trx 1蛋白質表現量減少，並且促使Trx 1氧化。接著我們利用N-acetylcysteine (NAC)與DL-buthionine-[S,R]-sulfoximine (BSO)來改變細胞內GSH含量，並在鎘的共同處理下觀察MT基因與Trx 1的變化。由實驗結果發現NAC可以恢復鎘處理造成的GSH消耗，降低MT基因的誘導與Trx 1的氧化，BSO則進一步導致Trx 1完全氧化。隨後將質體送入HEK293細胞中表現Trx 1或利用RNAi技術knockdown Trx 1表現，探討MT基因與GSH的相互關係。細胞內GSH含量不受Trx 1蛋白質表現而影響，驗證GSH與Trx是獨立的兩個系統。Knockdown Trx 1並與鎘共同處理之下，發現MT基因受到誘導的程度降低，可能是間接影響其他蛋白質活性，進而改變MTF-1調控MT基因的表現，其明確機制需更多的研究來加以證實。

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