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The flavonoid quercetin induces apoptosis and inhibits migration through a MAPK-dependent mechanism in osteoblasts

Tae Wook Nam1, Chong Il Yoo, Hui Taek Kim

  • 1Department of Orthopedic Surgery, Pusan National University, Pusan, Korea.

Journal of Bone and Mineral Metabolism
|November 4, 2008
PubMed

Insights

Quercetin, a dietary flavonoid, induces apoptosis in osteoblastic cells via mitochondrial pathways involving ERK activation. It also inhibits cell migration through ERK and p38 activation, suggesting complex roles in bone repair.

Area of Science:

  • Biochemistry
  • Cell Biology
  • Pharmacology

Background:

  • Quercetin is a prominent dietary flavonoid found in plant-based foods.
  • Flavonoids are known for their diverse biological activities.
  • Osteoblastic cells are crucial for bone formation and maintenance.

Purpose of the Study:

  • To investigate the effects of quercetin on osteoblastic cell viability and migration.
  • To elucidate the molecular mechanisms underlying quercetin's actions on these cells.

Main Methods:

  • Osteoblastic cells and adipose tissue-derived stromal cells were treated with quercetin.
  • Cell viability assays, apoptosis markers (Bax, caspase-3), mitochondrial membrane potential, and Western blot analysis were performed.
  • Specific inhibitors for ERK, p38, and JNK pathways were used.
  • Cell migration assays were conducted.

Main Results:

  • Quercetin inhibited osteoblastic cell viability and induced apoptosis in a dose- and time-dependent manner.
  • Quercetin protected against H(2)O(2)-induced cell death but increased TNF-alpha-induced cell death.
  • Apoptosis involved mitochondrial pathway activation (Bax, mitochondrial membrane potential) and caspase-3 activation, mediated by ERK.
  • Quercetin inhibited cell migration via ERK and p38 pathway activation.

Conclusions:

  • Quercetin induces apoptosis in osteoblastic cells through a mitochondria-dependent mechanism involving ERK activation.
  • Quercetin inhibits osteoblastic cell migration by activating ERK and p38 pathways.
  • Quercetin exhibits dual effects, potentially protective and detrimental, in bone repair processes.

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