Timekeeping in the hindbrain: a multi-oscillatory circadian centre in the mouse dorsal vagal complex

• Published in: Communications biology Vol. 3; no. 1; p. 225
• Main Authors: Chrobok, Lukasz, Northeast, Rebecca C, Myung, Jihwan, Cunningham, Peter S, Petit, Cheryl, Piggins, Hugh D
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 08.05.2020; Nature Publishing Group UK
• Subjects: Area postrema; Biology; Blood-brain barrier; Brain stem; Circadian rhythms; Clock gene; Gene expression; Hindbrain; Membrane permeability; Metabolism; Oscillators; Solitary tract nucleus; Vagus nerve
• ISSN: 2399-3642; 2399-3642
• DOI: 10.1038/s42003-020-0960-y

Metabolic and cardiovascular processes controlled by the hindbrain exhibit 24 h rhythms, but the extent to which the hindbrain possesses endogenous circadian timekeeping is unresolved. Here we provide compelling evidence that genetic, neuronal, and vascular activities of the brainstem's dorsal vagal complex are subject to intrinsic circadian control with a crucial role for the connection between its components in regulating their rhythmic properties. Robust 24 h variation in clock gene expression in vivo and neuronal firing ex vivo were observed in the area postrema (AP) and nucleus of the solitary tract (NTS), together with enhanced nocturnal responsiveness to metabolic cues. Unexpectedly, we also find functional and molecular evidence for increased penetration of blood borne molecules into the NTS at night. Our findings reveal that the hindbrain houses a local network complex of neuronal and non-neuronal autonomous circadian oscillators, with clear implications for understanding local temporal control of physiology in the brainstem.