biostudies-literatureNeri DU.S. Department of Health & Human Services | NIH | National Institute on Aging (U.S. National Institute on Aging)U.S. Department of Health & Human Services | NIH | National Institute of Diabetes and Digestive and Kidney Diseases (National Institute of Diabetes & Digestive & Kidney Diseases)U.S. Department of Health & Human Services | NIH | NIH Office of the Director (OD)313-326https://www.ebi.ac.uk/biostudies/studies/S-EPMC12945688biostudies-literatureUnknown8(2)Brown adipose tissue (BAT) contributes to thermoregulation and glucose metabolism, but how these functions are coordinated remains unclear. While thermogenesis in the activated BAT typically coincides with increased blood flow and glucose uptake^1-5, several pathophysiological and nutritional states dissociate these processes^6,7, suggesting they are governed by distinct sympathetic circuits. Here we identify subpopulations of sympathetic neurons in the stellate ganglion that mediate distinct functions of intrascapular BAT (iBAT) in mice. Two main types of sympathetic neurons project to iBAT: those that innervate the organ parenchyma and those that innervate the large blood vessels feeding the depot^8-12. Here we develop a toolkit to parse the functions of theNature metabolismDistinct sympathetic projections to brown fat regulate thermogenesis and glucose tolerance.PMC12945688S10OD034377R01DK125094OT2OD023853R56DK140355P01AG032959P30DK063608Lee SNair GMBozec DHeeren JHeine MWorthmann ANeri DThaker VVZeltser LMLafond AJGradinaru VFohn AMCastro E Souza LLopatinsky NRChen XRamos-Lobo AMfalseDistinct sympathetic projections to brown fat regulate thermogenesis and glucose tolerance.Brown adipose tissue (BAT) contributes to thermoregulation and glucose metabolism, but how these functions are coordinated remains unclear. While thermogenesis in the activated BAT typically coincides with increased blood flow and glucose uptake^1-5, several pathophysiological and nutritional states dissociate these processes^6,7, suggesting they are governed by distinct sympathetic circuits. Here we identify subpopulations of sympathetic neurons in the stellate ganglion that mediate distinct functions of intrascapular BAT (iBAT) in mice. Two main types of sympathetic neurons project to iBAT: those that innervate the organ parenchyma and those that innervate the large blood vessels feeding the depot^8-12. Here we develop a toolkit to parse the functions of the2026-01-01T00:00:00Z2026 Feb2026-07-16T22:18:15.085Z2026-07-11T03:11:48.08ZS-EPMC129456884155944510.1038/s42255-025-01429-0