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Okadaic acid induces apoptosis through the PKR, NF-κB and caspase pathway in human osteoblastic osteosarcoma MG63

Ling Chen1

  • 1Department of Histology and Oral Histology, Institute of Health Biosciences, University of Tokushima Graduate School, Kuramoto, Tokushima 770-8504, Japan. chenling982@163.com

Toxicology in Vitro : an International Journal Published in Association with BIBRA
|October 4, 2011
PubMed

Insights

Okadaic acid induces cell death in MG63 cells by triggering apoptosis. This process involves the protein kinase R (PKR), nuclear factor-kappa B (NF-κB), and caspase pathways, revealing key mechanisms of toxicity.

Area of Science:

  • Biochemistry
  • Cell Biology
  • Toxicology

Background:

  • Okadaic acid (OA) is a major diarrheic shellfish poisoning toxin.
  • OA is a potent inhibitor of protein phosphatase 1 and 2A.
  • Mechanisms of OA-induced cell death remain unclear.

Purpose of the Study:

  • Investigate OA's effects on MG63 cell apoptosis.
  • Characterize apoptotic morphological changes and DNA fragmentation.
  • Examine the roles of PKR, NF-κB, and caspase in OA-induced apoptosis.

Main Methods:

  • MG63 cells were treated with OA.
  • Apoptotic morphological changes and DNA fragmentation were analyzed.
  • Inhibitors of PKR, NF-κB (PDTC), caspase-3, and caspase-8 were used to block apoptosis.

Main Results:

  • OA induced cytotoxicity and apoptosis in MG63 cells (IC50 = 75 nM).
  • A functional PKR pathway was essential for OA-induced apoptosis.
  • Blocking NF-κB, caspase-3, or caspase-8 significantly reduced OA-induced apoptosis.

Conclusions:

  • OA induces apoptosis in MG63 cells.
  • The PKR, NF-κB, and caspase pathways are crucial mediators of OA-induced apoptosis.

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