Neuroprotective activity of honokiol and magnolol in cerebellar granule cell damage

Eur J Pharmacol. 2006 May 10;537(1-3):64-9. doi: 10.1016/j.ejphar.2006.03.035. Epub 2006 Mar 24.


The aim of the present study was to investigate the neuroprotective effects of honokiol and magnolol, two major bioactive constituents of the bark of Magnolia officinalis, against neuron toxicity induced by glucose deprivation, excitatory amino acids and hydrogen peroxide (H(2)O(2)) in cultured rat cerebellar granule cells. Cell membrane damage was measured with a lactate dehydrogenase (LDH) release assay and 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was used to assess mitochondrial activity, reflecting cell survival. Results showed that honokiol and magnolol alone did not affect mitochondrial function and cell damage, but significantly reversed glucose deprivation-induced mitochondrial dysfunction and cell damage. The glutamate receptor blocker MK-801 and antioxidant vitamin E also provided protection against this damage. Furthermore, honokiol was more potent than magnolol in protecting against glutamate-, N-methyl-D-aspartate (NMDA)- and H(2)O(2)-induced mitochondrial dysfunction. These results demonstrated that the neuroprotective effects of honokiol and magnolol may be related to their anti-oxidative actions and antagonism of excitotoxicity induced by excitatory amino acids, suggesting that both compounds may be potential therapeutic agents for neurodegenerative diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / pharmacology*
  • Biphenyl Compounds / pharmacology*
  • Cells, Cultured
  • Cerebellum / cytology
  • Cerebellum / metabolism
  • Dizocilpine Maleate / pharmacology
  • Excitatory Amino Acid Antagonists / pharmacology
  • Glucose / deficiency
  • Glutamic Acid / pharmacology
  • Hydrogen Peroxide / pharmacology
  • L-Lactate Dehydrogenase / metabolism
  • Lignans / pharmacology*
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • N-Methylaspartate / antagonists & inhibitors
  • N-Methylaspartate / pharmacology
  • Neurons / drug effects*
  • Neurons / metabolism
  • Neuroprotective Agents / pharmacology*
  • Oxidative Stress / drug effects
  • Rats
  • Rats, Sprague-Dawley
  • Vitamin E / pharmacology


  • Antioxidants
  • Biphenyl Compounds
  • Excitatory Amino Acid Antagonists
  • Lignans
  • Neuroprotective Agents
  • magnolol
  • honokiol
  • Vitamin E
  • Glutamic Acid
  • N-Methylaspartate
  • Dizocilpine Maleate
  • Hydrogen Peroxide
  • L-Lactate Dehydrogenase
  • Glucose