Neurons that regulate mouse torpor.
Level 5 - mechanism / opinion, no new human data
Preclinical animal study with no human data (CEBM level 5).
PubMed 32528180 · doi:10.1038/s41586-020-2387-5
What was done
Researchers investigated the neural mechanisms initiating and regulating fasting-induced torpor in mice. They examined medial and lateral preoptic hypothalamic neurons activated during prior torpor bouts to test whether artificial restimulation could trigger torpor in non-calorically restricted mice. They further characterized a specific population of glutamatergic Adcyap1-positive neurons through activity monitoring and targeted neuronal inhibition to determine their necessity in natural torpor entry, maintenance, and arousal.
What was found
The abstract reports no numerical sample sizes or quantitative metrics, other than describing baseline mouse torpor as characterized by body temperature reaching as low as 20 °C. Reactivation of previously torpor-active preoptic neurons successfully triggered key features of torpor in fed mice. Activity of glutamatergic Adcyap1-positive preoptic neurons determined the timing of natural torpor entry and exit, and their inhibition disrupted natural torpor entry, maintenance, and arousal.
Why it matters
The study identifies a specific hypothalamic neuronal subpopulation acting as a core regulator of mammalian torpor. These findings provide genetic access to study and manipulate hypothermic and hypometabolic states in mammals.
Limits
The study was conducted exclusively in mice; relevance to non-torpid mammals or humans is unestablished. The abstract does not disclose sample sizes, specific quantitative metabolic/temperature parameters during manipulation, or long-term safety and off-target effects of neural manipulation.
Cited by
- supports Stimulating preoptic neurons in mice to lower their core body temperature by approximately 3°C significantly slowed epigenetic aging across multiple organs.