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Current concepts of the mechanisms of menstruation: a normal process of tissue destruction

L A Salamonsen1

  • 1Prince Henry's Institute of Medical Research, PO Box 5152, Clayton, Victoria 3168, Australia.

Trends in Endocrinology and Metabolism: TEM
|April 15, 2008
PubMed

Insights

Menstruation results from matrix metalloproteinases (MMPs) in the endometrium, triggered by inflammation. Immune cells like macrophages and mast cells drive MMP production, leading to tissue breakdown and bleeding.

Area of Science:

  • Reproductive Biology
  • Immunology
  • Biochemistry

Background:

  • Menstruation involves complex endometrial tissue breakdown.
  • Matrix metalloproteinases (MMPs) are implicated in this process.
  • Inflammation is a key factor preceding menstruation.

Purpose of the Study:

  • To elucidate the role of MMPs in endometrial breakdown during menstruation.
  • To investigate the link between immune cells and MMP activation in the endometrium.
  • To understand the inflammatory triggers of menstruation.

Main Methods:

  • Localization of MMPs in perimenstrual endometrium.
  • Analysis of immune cell infiltration (mast cells, eosinophils, neutrophils, macrophages).
  • Assessment of MMP activity and endometrial matrix degradation.

Main Results:

  • MMPs are present in the perimenstrual endometrium.
  • Immune cells are closely associated with local MMP production and activation.
  • Degradation of interstitial matrix and basement membranes by MMPs contributes to menstruation.

Conclusions:

  • Menstruation is driven by MMPs activated by endometrial inflammation.
  • Immune cells play a critical role in regulating MMPs during the menstrual cycle.
  • MMP-mediated tissue degradation leads to endometrial bleeding.

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