In thermogenic brown adipose tissue, uncoupling protein 1 (UCP1) catalyzes the dissipation
of mitochondrial proton motive force as heat. In a cellular environment of high oxidative
capacity such as brown adipose tissue (BAT), mitochondrial uncoupling could also reduce
deleterious reactive oxygen species, but the specific involvement of UCP1 in this process is
disputed. By comparing brown adipose tissue mitochondria of wild type mice and UCP1-
ablated litter mates, we show that UCP1 potently reduces mitochondrial superoxide …