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Ablation of microglia does not alter circadian rhythm of locomotor activity.

ABSTRACT: Microglia, as macrophages in the brain, are responsible for immune responses and synaptic remodeling. Although the function of microglia is regulated by circadian rhythms, it is still unclear whether microglia are involved in the generation and light entrainment of circadian rhythms of behavior. Here, we report that microglial depletion does not alter behavioral circadian rhythms. We depleted ~ 95% of microglia in the mouse brain by PLX3397, a CSF1R inhibitor, and analyzed the effect on the spontaneous behaviors of mice. We found that neither the free-running period under constant darkness nor light entrainment under jet-lag circumstances were influenced by the ablation of microglia. Our results demonstrate that the circadian rhythms of locomotor activity, an important output of the circadian clock in the brain, are likely a phenomenon not produced by microglia.

SUBMITTER: Matsui F

PROVIDER: S-EPMC10080745 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Ablation of microglia does not alter circadian rhythm of locomotor activity.

Matsui Futaba F Yamaguchi Sho T ST Kobayashi Riho R Ito Shiho S Nagashima Sakimi S Zhou Zhiwen Z Norimoto Hiroaki H

Molecular brain 20230407 1

Microglia, as macrophages in the brain, are responsible for immune responses and synaptic remodeling. Although the function of microglia is regulated by circadian rhythms, it is still unclear whether microglia are involved in the generation and light entrainment of circadian rhythms of behavior. Here, we report that microglial depletion does not alter behavioral circadian rhythms. We depleted ~ 95% of microglia in the mouse brain by PLX3397, a CSF1R inhibitor, and analyzed the effect on the spon ...[more]

PMID: 37029416

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Effects of lithium on locomotor activity and circadian rhythm of honey bees.

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