FST and diabetic kidney disease: In this issue, Bian et al. evaluated the therapeutic potential of follistatin, a natural activin A antagonist, in C57BLKS/JLepr (db/db) mice treated with angiotensin II via subcutaneous osmotic mini pumps (1000 g/kg per minute).9 This well-established preclinical model of type 2 diabetes mellitus and DKD recapitulates key features of the disease, including glomerular and tubular injury and albuminuria.