Brown adipose tissue is specialized for non-shivering thermogenesis—burning calories to produce heat. Its best-characterized mechanism relies on uncoupling protein-1 (UCP1) in mitochondria, which allows cells to “burn fuel without work.” Yet scientists have long observed that mice lacking UCP1 can still stay warm and resist weight gain, implying that alternative heat-generating systems exist.
Finding those systems has become a priority as obesity and type 2 diabetes continue to rise worldwide. If physicians could safely raise a patient’s baseline energy expenditure, it might complement traditional weight-loss approaches focused on calorie intake and exercise.
Peroxisomes and ACOX2 take the stage
A study published in Nature now identifies one of those alternative systems. The team,