Disrupted daily rhythms may reduce nerve insulation by increasing Bmal1, leading to anxiety and depression-like behaviors

Circadian misalignment (CM) in mice led to a reduction in mature oligodendrocytes and the development of anxiety and depression-like behaviors.

• Long-term variable photoperiod (L-VP) caused phase delay and decreased amplitude in activity/rest rhythms of wild-type mice.
• Mice exposed to CM exhibited increased signs of anxiety and depression over time.
• A reduction in the number of mature oligodendrocytes was observed in the medial prefrontal cortex and hippocampal CA1 regions of CM mice.
• Restoration of a normal photoperiod did not reverse mood impairment or oligodendrocyte reduction.
• CM mice showed upregulation of the Bmal1 gene at night, which is linked to the expression of genes important for oligodendrocyte maturation.
• Inhibition of the AKT/mTOR signaling pathway was noted in CM mice, which is associated with oligodendrocyte differentiation.

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