Alpha Lipoic Acid Modulated High Glucose-Induced Rat Mesangial Cell Dysfunction via mTOR/p70S6K/4E-BP1 Pathway

Figure 4

Concentration-dependent LA regulated expressions of AMPK, AKT, mTOR, 4E-BP1, and p70S6K in high glucose-treated mesangial cells. MCs were preincubated for 1 h with high glucose (30 mmol/L) and then stimulated with various concentrations (0.1–1.0 mmol/L) of LA for 24 h, respectively. The relative quantitation of AMPKα mRNA was expressed as the ratio of AMPKα/β-actin (a), which in normal glucose cells was set to 1. Phosphorylation of AMPKα (b), AKT (c), mTOR (d), 4E-BP1 (e), and p70S6K (f) was determined by immunoblot analysis. β-Actin was used as a control to ensure equal protein loading. Representative blots (top) and densitometric analyses (bottom) are shown. Values are given as mean ± SD from three independent experiments; was considered statistically significant. Note: ^* versus NG; ^# versus HG. Abbreviations: NG, normal glucose (5 mM); Man (5 mM glucose + 25 mM mannitol); HG, high glucose (30 mM).