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Updated: Aug 29, 2026

Optimized Protocol for the Extraction of Proteins from the Human Mitral Valve
09:13

Optimized Protocol for the Extraction of Proteins from the Human Mitral Valve

Published on: June 14, 2017

Fibrillin and other matrix proteins in mitral valve prolapse syndrome

Joseph F Nasuti1, Paul J Zhang, Michael D Feldman

  • 1Hospital of University of Pennsylvania, Philadelphia, PA, USA.

The Annals of Thoracic Surgery
|February 5, 2004
PubMed
Abstract

Insights

Abnormalities in fibrillin and other matrix proteins likely cause myxomatous degeneration in mitral valve prolapse syndrome (MVPS). This study found distinct extracellular matrix protein distribution differences in MVPS leaflets compared to normal and rheumatic heart disease valves.

Area of Science:

  • Cardiovascular Biology
  • Extracellular Matrix Research
  • Molecular Pathology

Background:

  • Myxomatous degeneration in Marfan syndrome is linked to fibrillin gene mutations.
  • The molecular cause of myxomatous degeneration in mitral valve prolapse syndrome (MVPS) remains unclear.
  • This study investigates extracellular matrix protein distribution in isolated MVPS.

Purpose of the Study:

  • To examine the distribution of fibrillin and other extracellular matrix proteins in mitral valve leaflets from patients with isolated MVPS.
  • To compare these distributions with those in normal mitral valves and valves affected by rheumatic heart disease (RHD).

Main Methods:

  • Immunohistochemical analysis of mitral valve leaflets from 7 MVPS patients, 5 RHD patients, and 5 normal controls.
  • Characterization of fibrillin, elastin, collagen I, and collagen III distribution.

Main Results:

  • Normal valves show a laminar pattern of fibrillin, elastin, and collagens.
  • MVPS leaflets with myxoid degeneration exhibit diffuse, weaker, and nonlaminar staining for fibrillin and other matrix proteins.
  • RHD valves show localized disruption of extracellular proteins, preserving overall architecture, unlike the diffuse changes in MVPS.

Conclusions:

  • Abnormalities in fibrillin and other extracellular matrix proteins play a primary role in myxoid degeneration of mitral valve leaflets in MVPS.
  • These findings highlight a distinct molecular basis for MVPS compared to other valvular diseases.

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