Glutathione reductase (GR), an essential antioxidant enzyme against oxidative stress, has become an attractive drug target for the development of anticancer and antimalarial drugs. In this regard, we evaluated the naturally occurring isothiocyanates as promising GR inhibitors and elucidated the mechanism of action. It was found that benzyl isothiocyanate (BITC) and phenethyl isothiocyanate (PEITC) inhibited yeast GR (yGR) and human GR (hGR) in a time- and concentration-dependent manner. The K_i and k_inact of BITC against yGR were determined to be 259.87 µM and 0.0266 min⁻¹, respectively. The GR inhibition occurred only in the presence of NADPH and persisted after extensive dialysis. The tandem mass spectrometric analysis revealed that Cys⁶¹ rather than Cys⁶⁶ at the active site of yGR was mono-benzyl thiocarbamoylated by BITC. Inhibition of intracellular GR by BITC and PEITC in cultured cancer cells was also observed. BITC and PEITC were evaluated as competitive and irreversible inhibitors of GR.

谷胱甘肽还原酶（GR）是一种抗氧化应激的重要抗氧化酶，已成为开发抗癌和抗疟疾药物的有吸引力的药物靶标。在这方面，我们评估了天然存在的异硫氰酸酯作为有前途的GR抑制剂，并阐明了其作用机理。已发现异硫氰酸苄酯（BITC）和异硫氰酸苯乙酯（PEITC）以时间和浓度依赖性方式抑制酵母GR（yGR）和人GR（hGR）。的ķ_我 和ķ _INACT BITC的针对YGR被确定为259.87μM和0.0266分钟^-1， 分别。GR抑制仅在NADPH存在下发生，并在广泛透析后持续存在。串联质谱分析显示，yGR活性位点的Cys ⁶¹而不是Cys ⁶⁶是BITC的单苄基硫代氨基甲酰化。还观察到BITC和PEITC在培养的癌细胞中抑制细胞内GR。BITC和PEITC被认为是GR的竞争性和不可逆抑制剂。