25-Hydroxycholesterol-Induced Oxiapoptophagy in L929 Mouse Fibroblast Cell Line

Molecules. 2021 Dec 29;27(1):199. doi: 10.3390/molecules27010199.


25-hydroxycholesterol (25-HC) is an oxysterol synthesized from cholesterol by cholesterol-25-hydroxylase during cholesterol metabolism. The aim of this study was to verify whether 25-HC induces oxiapoptophagy in fibroblasts. 25-HC not only decreased the survival of L929 cells, but also increased the number of cells with condensed chromatin and altered morphology. Fluorescence-activated cell sorting results showed that there was a dose-dependent increase in the apoptotic populations of L929 cells upon treatment with 25-HC. 25-HC-induced apoptotic cell death was mediated by the death receptor-dependent extrinsic and mitochondria-dependent intrinsic apoptosis pathway, through the cascade activation of caspases including caspase-8, -9, and -3 in L929 cells. There was an increase in the levels of reactive oxygen species and inflammatory mediators such as inducible nitric oxide synthase, cyclooxygenase-2, nitric oxide, and prostaglandin E2 in L929 cells treated with 25-HC. Moreover, 25-HC caused an increase in the expression of beclin-1 and microtubule-associated protein 1A/1B-light chain 3, an autophagy biomarker, in L929 cells. There was a significant decrease in the phosphorylation of protein kinase B (Akt) in L929 cells treated with 25-HC. Taken together, 25-HC induced oxiapoptophagy through the modulation of Akt and p53 cellular signaling pathways in L929 cells.

Keywords: 25-hydroxycholesterol; apoptosis; oxiapoptophagy; oxidative stress; oxysterol.

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Autophagy / drug effects*
  • Cell Death / drug effects
  • Cell Line
  • Cell Survival / drug effects
  • Fibroblasts / drug effects*
  • Fibroblasts / metabolism*
  • Hydroxycholesterols / chemistry
  • Hydroxycholesterols / pharmacology*
  • Inflammation Mediators / metabolism
  • Mice
  • Mitochondria
  • Molecular Structure
  • Oxidative Stress / drug effects*
  • Reactive Oxygen Species / metabolism


  • Hydroxycholesterols
  • Inflammation Mediators
  • Reactive Oxygen Species
  • 25-hydroxycholesterol