Parabrachial neurons orchestrate cold-induced homeostatic responses

Area of Science:

• Neuroscience
• Physiology
• Thermoregulation

Background:

• Thermoregulation is vital for survival, but central processing of cold sensation and adaptive responses are not fully understood.
• The brain's role in integrating peripheral cold signals to orchestrate diverse physiological and behavioral adaptations requires further elucidation.

Purpose of the Study:

• To identify and characterize brain neurons that receive and process peripheral cold sensory information.
• To investigate the role of these identified neurons in coordinating various cold-adaptive responses and maintaining thermal homeostasis.

Main Methods:

• Utilized activity-dependent genetic labeling in mice to identify cold-activated neurons in the parabrachial nucleus (PB).
• Performed neuronal silencing and activation experiments to assess functional roles.
• Conducted molecular profiling to identify specific markers for these neurons.

Main Results:

• Identified cold-activated neurons in the parabrachial nucleus (PB^Cold neurons) as primary recipients of cold sensory input.
• PB^Cold neurons show sustained activation by cold stimuli, encoding environmental cooling.
• Silencing PB^Cold neurons disrupts autonomic, somatic, behavioral, metabolic, and affective cold responses, impairing survival in severe cold.
• Activation of PB^Cold neurons promotes warmth-seeking, increases food intake, and boosts energy expenditure.

Conclusions:

• PB^Cold neurons represent a critical central hub for coordinating diverse cold-responsive adaptations.
• These findings advance the understanding of neural mechanisms governing thermal homeostasis and survival in cold environments.