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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Morphine promotes apoptosis via TLR2, and this is negatively regulated by beta-arrestin 2

Yi Li1, Xiuli Sun, Yi Zhang

  • 1Department of Neurology, The Second Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.

Biochemical and Biophysical Research Communications
|December 17, 2008
PubMed

Insights

Morphine induces apoptosis via Toll-like receptor 2 (TLR2) signaling. Beta-arrestin 2 acts as a negative regulator, mitigating this morphine-induced cell death pathway.

Area of Science:

  • Immunology
  • Cell Biology
  • Pharmacology

Background:

  • Morphine is known to induce apoptosis, but the molecular mechanisms are unclear.
  • Toll-like receptor 2 (TLR2) influences cell survival and death.
  • Beta-arrestin 2 may regulate innate immune responses mediated by TLRs.

Purpose of the Study:

  • To investigate the roles of TLR2, MyD88, and beta-arrestin 2 in morphine-induced apoptosis.
  • To elucidate the signaling pathway involved in morphine-induced cell death.

Main Methods:

  • Overexpression of TLR2 in HEK293 cells.
  • Inhibition of MyD88 using dominant-negative MyD88.
  • Overexpression of beta-arrestin 2.
  • Assessment of morphine-induced apoptosis.

Main Results:

  • Overexpressing TLR2 significantly increased morphine-induced apoptosis in HEK293 cells.
  • Inhibiting MyD88 or overexpressing beta-arrestin 2 attenuated morphine-induced apoptosis in TLR2-overexpressing cells.

Conclusions:

  • Toll-like receptor 2 (TLR2) signaling mediates morphine-induced apoptosis.
  • Beta-arrestin 2 functions as a negative regulator in this TLR2-mediated apoptotic pathway.

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