Fig 3.

ActRIIB inhibition increases lipid but not mitochondrial density. (A) Lipid droplet size was analyzed on hematoxylin-eosin-stained sections from interscapular BAT using automated detection and quantification software (n = 5/group). *, P < 0.05. (B) Mitochondrial DNA was quantified after DNA extraction by amplifying the mitochondrial gene cytochrome b by TaqMan quantitative PCR and normalizing to the levels of two probes detecting genomic DNA. (C) Interscapular brown adipose tissue from control and ActRIIB Ab-treated mice (20 mg/kg/week) was imaged by electron microscopy (C). L, lipid droplet; e, erythrocyte; N, nucleus, m, mitochondrion. Bars, 0.5 μm.