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TGF-β1 regulates pannexin1 channels and evokes apoptotic response in osteoblasts

Wenjing Liu1

  • 1Yan'an Medical College of Yan'an University, Yan'an, China.

Archives of Oral Biology
|June 25, 2025
PubMed
Abstract

Insights

High concentrations of transforming growth factor-beta 1 (TGF-β1) increase pannexin1 expression and channel activity in osteoblasts. This process, mediated by the ERK signaling pathway, leads to osteoblast apoptosis.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Extracellular ATP influences cell-cell interactions.
  • Transforming growth factor-beta 1 (TGF-β1) is known to stimulate ATP release via pannexin1 channels.
  • The precise role of TGF-β1 in regulating pannexin1 channels and osteoblast apoptosis requires elucidation.

Purpose of the Study:

  • To investigate the role of TGF-β1 in modulating pannexin1 channels and osteoblast apoptosis.
  • To clarify the signaling pathways involved in TGF-β1-induced pannexin1 regulation.

Main Methods:

  • Immunofluorescence labeling and western blot analysis to detect pannexin1 expression.
  • Dye uptake assays to measure pannexin1 channel activity.
  • MEK inhibitor (U0126) to block ERK signaling.
  • Flow cytometry to assess osteoblast apoptosis rates.

Main Results:

  • TGF-β1 significantly increased pannexin1 expression in primary osteoblasts and MC3T3 cells.
  • TGF-β1 enhanced osteoblast dye uptake through pannexin1 channels.
  • Inhibition of the ERK signaling pathway abrogated TGF-β1's effect on pannexin1.
  • Pannexin1 expression was elevated in osteoblasts undergoing apoptosis induced by high TGF-β1 concentrations.

Conclusions:

  • High concentrations of TGF-β1 up-regulate pannexin1 expression and activate its channels in osteoblasts.
  • The ERK signaling pathway is a key mediator of TGF-β1's regulation of pannexin1.
  • This TGF-β1-pannexin1-ERK axis ultimately induces osteoblast apoptosis.
Keywords:
ApoptosisERKOsteoblastsPannexin1TGF-β1

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