STK11 and gestational diabetes: Therefore, the upstream kinases that phosphorylate the activation site of AMPK at Thr172, including liver kinase B 1 (LKB1) (Sakamoto et al., 2006), calcium–calmodulin-dependent kinase kinase-β (CaMKKβ) (Woods et al., 2005) and transforming growth factor-β-activated protein kinase-1 (TAK1), should be further investigated to determine the mechanism through which AMPK signaling is inhibited in placentas from GDM pregnancies.