Fig. 1: Exosomes from cold-activated hepatocytes enhance BAT thermogenesis.

A HepExos were successfully delivered to the target BAT. Scale bar: 200 μm. B The in vivo experimental protocol involved the administration of cold-exposed exosomes via tail vein injection. C Body weight measurements of the mice in group (B) were recorded, with n = 5 mice per group. D Rectal temperature was assessed in mice from group (B) when exposed to a temperature of 4°C, with n = 5 mice per group. E The mass of fat and liver tissues was measured in mice from group (B), with n = 5 mice per group. F The oxygen consumption rate in BAT was determined using Clark electrodes, as described for group (B), across n = 5 independent experiments. G Gene expression in BAT was evaluated through quantitative PCR, as conducted in group (B), with n = 5 independent experiments. H UCP1 protein levels were quantified in immortalized brown adipocytes, primary BAT cells, and BAT tissue, with n = 3 independent experiments. I C57BL/6 J male mice underwent indirect calorimetry analysis under basal conditions, with n = 5 mice per group. J Hematoxylin and eosin staining was performed on BAT samples from mice in group (B). Scale bar: 0.2 mm for BAT, iWAT, and eWAT.