38.
Structure-activity relationship of schisandrins in
enhancing liver mitochondrial glutathione status in CCl4-poisoned mice.
Department of Biochemistry, Hong Kong University of Science & Technology, Clear Water Bay, China.
AIM: To explore whether the methylenedioxy group and cyclooctadiene
ring of the dibenzocyclooctadiene skeleton of schisandrins (Sch) play a role in
the liver mitochondrial glutathione status enhancing activity. METHOD: The
effects of three dibenzocyclooctadiene derivatives, Sch A, Sch B, Sch
C, and a synthetic intermediate of Sch C, (dimethyl biphenyl dicarboxylate,
DBD) on carbon tetrachloride (CCl4)-hepatotoxicity
and liver mitochondrial glutathione status were examined in mice. RESULTS: Pretreating mice with intragastric
Sch B, Sch C, or DBD
1.mmol.kg-1.d-1 for 3 d protected against CCl4-hepatotoxicity. The hepatoprotection afforded by Sch
B or Sch C pretreatment was associated with increases
in liver mitochondrial reduced glutathione (mtGSH)
level and glutathione reductase (mtGRD)
activity, an indication of enhanced mitochondrial glutathione status. In
contrast, the hepatoprotective action of DBD was not
accompanied by any detectable changes in mtGSH level
and mtGRD activity. CONCLUSION: Both the methylenedioxy group and the cyclooctadiene
ring of the dibenzocyclooctadiene molecule are
important structural determinants in the enhancement of liver mitochondrial
glutathione status.