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

Figure 5

LY294002 prevented the phosphorylation of AKT, mTOR, p70S6K, and 4E-BP1 induced by 0.25 mM LA in high glucose-cultured MCs. Cells were preincubated with high glucose medium for 1 h and then stimulated with different concentrations of LY294002 in the presence of 0.25 mM LA for an additional 24 h. The phosphorylation of AKT ((a) panel (A)), mTOR ((a) panel (B)), 4E-BP1 ((a) panel (C)), and p70S6K ((a) panel (D)) was determined by immunoblot analysis. STO-609 reversed the phosphorylation of AMPK, mTOR, p70S6K, and 4E-BP1 induced by 1.0 mM LA in high glucose-treated MCs. Cells were preincubated with high glucose medium for 1 h and then stimulated with various concentrations of STO-609 in the presence of 1.0 mM LA for 24 h. The phosphorylation of AMPK ((b) panel (A)), mTOR ((b) panel (B)), 4E-BP1 ((b) panel (C)), and p70S6K ((b) panel (D)) in cells was determined by immunoblot analysis. β-Actin was used as a control to ensure equal protein loading. Representative blots (left) and densitometric analyses (right) are shown. Values are given as mean ± SD; 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).

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