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Updated: Jun 4, 2026

Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes
15:43

Assessment of Mitochondrial Functions and Cell Viability in Renal Cells Overexpressing Protein Kinase C Isozymes

Published on: January 7, 2013

Adenosine activates AMPK to phosphorylate Bcl-XL responsible for mitochondrial damage and DIABLO release in HuH-7

Donqin Yang1, Takahiro Yaguchi, Takashi Nakano

  • 1Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, Nishinomiya, Japan.

Cellular Physiology and Biochemistry : International Journal of Experimental Cellular Physiology, Biochemistry, and Pharmacology
|February 18, 2011
PubMed
Abstract

Insights

Adenosine triggers apoptosis in liver cancer cells by activating AMP-activated protein kinase (AMPK), disrupting mitochondrial function, and activating caspase-3. This research clarifies the AMPK signaling pathway in cancer cell death.

Area of Science:

  • Cell Biology
  • Molecular Oncology
  • Biochemistry

Background:

  • AMP-activated protein kinase (AMPK) is increasingly recognized for its role in inducing apoptosis across various cancer types.
  • Understanding the specific signaling mechanisms by which AMPK influences cancer cell death is crucial for therapeutic development.

Purpose of the Study:

  • To elucidate the role of AMP-activated protein kinase (AMPK) signaling in adenosine-induced apoptosis of HuH-7 liver cancer cells.
  • To investigate the molecular events downstream of AMPK activation, including mitochondrial integrity and caspase activation.

Main Methods:

  • HuH-7 cells were treated with adenosine or AICAR (an AMPK activator).
  • Assays included cell viability, AMPK activity, mitochondrial membrane potential, Bcl-X(L) phosphorylation, DIABLO release, and caspase-3 activity.
  • Genetic manipulation involved transfecting cells with plasmids for DIABLO-GFP, mutant Bcl-X(L), dominant-negative AMPKα2, and siRNAs for AMPKα1/α2.

Main Results:

  • Adenosine and AICAR induced apoptosis in HuH-7 cells, with no synergistic effect observed upon co-treatment.
  • Adenosine activated AMPK, leading to Bcl-X(L) phosphorylation and disruption of mitochondrial membrane potential.
  • These effects were significantly inhibited by AMPK knockdown, dominant-negative AMPKα2 expression, or mutant Bcl-X(L).
  • AICAR promoted DIABLO release and caspase-3 activation, which were attenuated by mutant Bcl-X(L).

Conclusions:

  • Adenosine activates AMPK, which subsequently phosphorylates Bcl-X(L), leading to mitochondrial membrane potential disruption.
  • This mitochondrial disruption facilitates DIABLO release, a key event in the activation of caspase-3 and subsequent apoptosis induction in HuH-7 cells.

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