叔丁基对苯二酚上调Nrf2调控的基因表达并减轻环磷酰胺导致的小鼠血液毒性

血液毒性（或称骨髓抑制）是癌症化疗最常见的剂量限制毒副作用,而转录因子Nrf2控制着包括骨髓在内的许多组织对化学刺激的敏感性。本文研究了叔丁基对苯二酚（tBHQ）对小鼠外周血细胞中Nrf2调控的基因表达和环磷酰胺（CTX）导致的血液毒性的影响。CTX处理导致了小鼠外周血有核细胞的凋亡和白细胞减少,伴随着骨髓造血细胞的动员。tBHQ处理则可以在体外和体内激活RAW264.7小鼠巨噬细胞和外周血细胞中Nrf2信号和下游基因如血红素氧化酶1和谷胺酸半胱氨酸连接酶催化亚基等的表达同时,tBHQ预处理可以减轻CTX导致的小鼠外周血有核细胞的凋亡和白细胞减少,说明Nrf2可能在减轻CTX血液毒性中发挥作用。本文的研究有助于加深对化疗所致血液毒性的了解,并提示Nrf2可能作为减轻化疗毒副作用的化疗保护剂的药物靶标。

Upregulation of Nrf2-regulated gene expression by tBHQ alleviates cyclophosphamide-induced hematotoxicity in mice

Hematological toxicity （bone marrow suppression） is the most common dose-limiting adverse effect of chemotherapies. The nuclear factor erythroid 2-related factor 2 （Nrf2） is a pivotal coordinator of cellular defensive responses against chemical insults in many tissues including bone marrow. In the present study, the effects of tert-butylhydroquinone （tBHQ） on the expression of Nrf2-regulated genes in peripheral blood cells and cyclophosphamide （CTX）-induced hematotoxicity in mice were investigated. CTX induced apoptosis of peripheral blood nucleated cells and leukopenia in mice, accompanied by mobilization of bone marrow hematopoietic cells, tBHQ treatment induced the expression of Nrf2-regulated genes such as heine oxygenase 1 （HO1） and glutamate-cysteine ligase catalytic subtmit （GCLC） in RAW264.7 mouse macrophage cells and peripheral blood cells both in vitro and in vivo. Interestingly, pretreatment with tBHQ alleviated CTX-induced mouse peripheral blood cell apoptosis and leukopenia in vivo, indicating possible involvement of Nrf2 in the protection against CTX-induced hematotoxicity. This study provides new information on the chemotherapy-induced hematotoxicity, and suggests Nrf2 could serve as a target for the development of chemoprotectants against hematotoxicity.