Selenium helps the body clock protect mice from chemotherapy toxicity by increasing the core clock protein BMAL1

L-methyl-selenocysteine up-regulates BMAL1 expression in both cultured cells and mice.

• Selenium compounds may reduce toxicity associated with anti-cancer treatments in certain models.
• The circadian clock influences sensitivity to chemotherapy toxicity.
• L-methyl-selenocysteine acts as a positive regulator of the core clock protein BMAL1.
• Selenium's mechanism involves interference with TIEG1, which represses BMAL1 expression.
• Selenium does not protect BMAL1-deficient mice from chemotherapy toxicity but does protect Clock mutant mice with normal BMAL1.
• These findings suggest that selenium may enhance tissue protection through up-regulation of BMAL1.

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