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Updated: Jun 22, 2026

Mechanism of Regulation of Adipocyte Numbers in Adult Organisms Through Differentiation and Apoptosis Homeostasis
08:34

Mechanism of Regulation of Adipocyte Numbers in Adult Organisms Through Differentiation and Apoptosis Homeostasis

Published on: June 3, 2016

Polymethoxyflavones activate Ca2+-dependent apoptotic targets in adipocytes

Igor N Sergeev1, Shiming Li, Chi-Tang Ho

  • 1Department of Nutrition, Food Science, South Dakota State University, Brookings, South Dakota 57007, USA. igor.sergeev@sdstate.edu

Journal of Agricultural and Food Chemistry
|June 16, 2009
PubMed

Insights

Polymethoxyflavones (PMFs) trigger apoptosis in fat cells by increasing intracellular calcium, activating calpain and caspase-12. This discovery offers a new strategy for obesity treatment and long-lasting weight management.

Area of Science:

  • Biochemistry
  • Cell Biology
  • Metabolic Disorders

Background:

  • Apoptosis (programmed cell death) of adipocytes is a promising strategy for obesity treatment.
  • Polymethoxyflavones (PMFs) have shown apoptosis-inducing effects in cancer cells via calcium signaling.
  • Intracellular calcium (Ca2+) plays a key role in apoptosis induction.

Purpose of the Study:

  • To investigate the effect of PMFs on apoptosis in mature mouse 3T3-L1 adipocytes.
  • To elucidate the molecular mechanisms underlying PMF-induced adipocyte apoptosis, focusing on calcium signaling pathways.

Main Methods:

  • Treatment of 3T3-L1 adipocytes with varying concentrations and durations of PMFs.
  • Measurement of intracellular Ca2+ levels.
  • Assay of calpain and caspase-12 activity.
  • Assessment of apoptosis induction.

Main Results:

  • PMFs induced apoptosis in 3T3-L1 adipocytes in a concentration- and time-dependent manner.
  • PMF treatment led to a sustained increase in intracellular Ca2+ levels.
  • This increase in Ca2+ was associated with the activation of mu-calpain and caspase-12.
  • Hydroxylated PMFs exhibited significantly higher apoptosis-inducing activity compared to nonhydroxylated forms.

Conclusions:

  • PMFs induce adipocyte apoptosis through the activation of Ca2+-dependent calpain and caspase-12.
  • These findings support the potential of PMFs as therapeutic agents for obesity prevention and treatment by targeting fat cell reduction.

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