Fig. 4

Glucose modulates cell growth and lactose synthesis via AKT1 activation. Nonspecific scrambled siRNA (Scr) was used as a negative control in all experiments. a Relative AKT1 mRNA levels in siRNA-transfected dairy cow mammary epithelial cells. The mRNA levels were measured by qPCR and normalized to β-ACTIN mRNA. b, c Western blot analysis (b) and quantification (c) of AKT1 in siRNA-transfected dairy cow mammary epithelial cells. The protein levels were normalized to β-ACTIN. d, e, f The effect of glucose concentration on lactose synthesis (d), cell viability (e), and proliferation (f) in dairy cow mammary epithelial cells when cells were transiently transfected with AKT1 siRNA. siRNA-transfected dairy cow mammary epithelial cells were cultured in DMEM with glucose at concentrations ranging from 0 to 20 mM for 24 h. The effect of glucose concentration on lactose content, cell viability, and proliferation were examined. Data are shown as the mean ± SEM from 3 independent replicates. *P < 0.05; **P < 0.01