Inhibitory effects of salvianolic acid B on apoptosis of Schwann cells and its mechanism induced by intermittent high glucose

Life Sci. 2012 Jan 16;90(3-4):99-108. doi: 10.1016/j.lfs.2011.10.001. Epub 2011 Oct 20.

Abstract

Aims: To investigate protective effects of Salvianolic acid B (Sal B) on the intermittent high glucose (IHG)-induced oxidative stress, mitochondrial pathway activation and Schwann cell (SC) apoptosis in vitro.

Main methods: SCs were primarily cultured and exposed to the different conditions. Apoptosis was confirmed by the Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method and concentration of 8-hydroxy-2-deoxy Guanosine (8-OHdG) was detected by Elisa. Intracellular ROS generation and mitochondrial transmembrane potential (ΔΨm) were detected by flow cytometry analysis. Quantitative real-time reverse transcriptase PCR was performed to analyze the expression levels of Bax and BcL-2. Western blot was performed to analyze the expression levels of some important transcription factors and proteins.

Key findings: Treatment with Sal B inhibited the IHG-induced oxidative stress by reducing ROS production and 8-OHdG levels, mitochondrial depolarization and apoptosis in SCs in a dose-dependent manner. Furthermore, treatment with Sal B down-regulated the IHG-induced release of cytochrome c, AIF nuclear translocation and Bax expression, but mitigated the IHG-mediated down-regulation of BcL-2 expression in SCs. In addition, treatment with Sal B attenuated the IHG-induced activation of caspase-9 and caspase-3 and minimized the cleavage of PARP in SCs.

Significance: Our results indicated that IHG induced SC apoptosis in both caspase-dependent and caspase-independent pathways by activating the mitochondrial pathway. Sal B inhibited the IHG-induced oxidative stress, activation of the mitochondrial pathway and apoptosis in SCs.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Apoptosis / drug effects*
  • Apoptosis / physiology*
  • Benzofurans / pharmacology*
  • Cells, Cultured
  • Drugs, Chinese Herbal / pharmacology*
  • Glucose / administration & dosage*
  • Oxidative Stress / drug effects
  • Oxidative Stress / physiology
  • Rats
  • Rats, Sprague-Dawley
  • Schwann Cells / drug effects
  • Schwann Cells / metabolism*

Substances

  • Benzofurans
  • Drugs, Chinese Herbal
  • salvianolic acid B
  • Glucose