TRPA1 deficiency alters brown adipose tissue proteome and thermogenic gene expression during cold exposure in mice.

TRPA1 channels function as cold sensors and have been implicated in energy metabolism. We investigated the impact of TRPA1 on thermoregulation. Trpa1 -/- mice exhibited body weight loss and increased food intake when transitioning from 30°C to mild cold (14 days at 22°C), indicating increased energy metabolism in response to cold. Trpa1 -/- mice exhibited elevated oxygen consumption, while their core temperature remained unaffected. The BAT proteome in WT mice after 14 days at 22°C showed increased proteins related to glucose utilization and reduced proteins related to lipolysis, whereas Trpa1 -/- mice revealed increased PRDM16 and proteins associated with peroxisomal/mitochondrial β-oxidation. Transcripts of Cidea, Ucp1, Cpt1a, and Lcad were higher in Trpa1 -/- mice at 22°C compared to 30°C, relative to WT mice, with Prdm16 expression uniquely increased in Trpa1 -/- mice. Thermographic images revealed higher interscapular surface temperature in Trpa1 -/- mice exposed to 22°C. These data suggest that the TRPA1 channel reduces metabolic stress and contributes to thermogenic regulation in mice.