Lipid imaging by gold cluster time-of-flight secondary ion mass spectrometry: application to Duchenne muscular dystrophy

David Touboul,Alain Brunelle,Frédéric Halgand,Sabine De La Porte,Olivier Laprévote

doi:10.1194/jlr.m500058-jlr200

Abstract

Imaging with time-of-flight secondary ion mass spectrometry (TOF-SIMS) has expanded very rapidly with the development of gold cluster ion sources (Au(3+)). It is now possible to acquire ion density maps (ion images) on a tissue section without any treatment and with a lateral resolution of few micrometers. In this article, we have taken advantage of this technique to study the degeneration/regeneration process in muscles of a Duchenne muscular dystrophy model mouse. Specific distribution of different lipid classes (fatty acids, triglycerides, phospholipids, tocopherol, coenzyme Q9, and cholesterol) allows us to distinguish three different regions on a mouse leg section: one is destroyed, another is degenerating (oxidative stress and deregulation of the phosphoinositol cycle), and the last one is stable. TOF-SIMS imaging shows the ability to localize directly on a tissue section a great number of lipid compounds that reflect the state of the cellular metabolism.

Highlights

Imaging with time-of-flight secondary ion mass spectrometry (TOF-SIMS) has expanded very rapidly with the development of gold cluster ion sources (Au3؉)
The first one is based on matrix-assisted laser desorption ionization (MALDI) [1, 2] coupled with a timeof-flight (TOF) technique, which leads to the acquisition of images in a mass range from 500 to a few tens of thousands daltons with a spatial resolution of ‫ف‬50 ␮m [3, 4], and the second one is based on TOF secondary ion mass spectrometry (SIMS), which leads to the acquisition of images with masses of Ͻ1,000 Da with a spatial resolution of 1 ␮m or less [5,6,7]
One of the origins of oxidative stress is the increase of the nitric oxide (NO·) level that is provided by nitric oxide synthase (NOS)

Summary

Introduction

Imaging with time-of-flight secondary ion mass spectrometry (TOF-SIMS) has expanded very rapidly with the development of gold cluster ion sources (Au3؉). The first one is based on matrix-assisted laser desorption ionization (MALDI) [1, 2] coupled with a timeof-flight (TOF) technique, which leads to the acquisition of images in a mass range from 500 to a few tens of thousands daltons with a spatial resolution of ‫ف‬50 ␮m [3, 4], and the second one is based on TOF secondary ion mass spectrometry (SIMS), which leads to the acquisition of images with masses of Ͻ1,000 Da with a spatial resolution of 1 ␮m or less [5,6,7] In both cases, tissue sections having a thickness of 10–20 ␮m are cut using a cryostat at Ϫ20ЊC and transferred to target plates (stainless steel or glass). This variation was linked to a cellular fusion process and indicated a regeneration in a destructured area of the muscle [17]

Results

Discussion

Conclusion