Structurally diverse diterpenoids from Isodon oresbius and their bioactivity

Bioorg Chem. 2022 Jul:124:105811. doi: 10.1016/j.bioorg.2022.105811. Epub 2022 Apr 16.

Abstract

Twelve new diterpenoids, isoresbins A-L (1-12), together with twenty-eight known ones, were isolated from the aerial parts of Isodon oresbius. Their diverse structures included 6,7-seco-ent-kaurane, 7,20-epoxy-ent-kaurane, 6,7:8,15-diseco-ent-kaurane, and abietanes skeletons, which were elucidated by spectroscopic data interpretation, single-crystal X-ray diffraction, and quantum chemical calculation. Isoresbins A (1) and B (2) possessed a new rearranged 15(8 → 11)-abeo-6,7-seco-ent-kaurane skeleton. 1 and 5 promoted lysosomal function, which was evaluated by LysoTracker Red staining and DQ-ovalbumin dequenching assay. 1 showed cytotoxicity against six human tumor cell lines with IC50 values in 2.07-4.04 μM range. Moreover, 1 induced damage of mitochondrial membrane potential, G2/M cell cycle arrest and apoptosis in SW480 cells.

Keywords: Apoptosis; Cytotoxicity; Diterpenoids; Isodon oresbius; Lysosomal activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Phytogenic* / chemistry
  • Antineoplastic Agents, Phytogenic* / pharmacology
  • Diterpenes* / pharmacology
  • Diterpenes, Kaurane* / chemistry
  • Diterpenes, Kaurane* / pharmacology
  • Drug Screening Assays, Antitumor
  • Humans
  • Isodon* / chemistry
  • Molecular Structure

Substances

  • Antineoplastic Agents, Phytogenic
  • Diterpenes
  • Diterpenes, Kaurane