Home › Analytical Chem › MALDI Imaging Mass Spectrometry of Neuropeptides in Parkinson's Disease
Analytical Chem JoVE (Open Access) Citable · DOI

MALDI Imaging Mass Spectrometry of Neuropeptides in Parkinson's Disease

DOI: 10.3791/3445-v
What you'll learn
  • ✓ Prepare and mount brain tissue sections for MALDI imaging mass spectrometry
  • ✓ Apply matrix and acquire neuropeptide mass spectrometry data from rat brain regions
  • ✓ Process and visualize spatial neuropeptide distribution changes in Parkinson's disease models
  • ✓ Validate MALDI-detected neuropeptides using complementary analytical techniques
Protocol

Dopamine replacement pharmacotherapy using L-DOPA is the most commonly used symptomatic treatment of Parkinson’s disease, but is accompanied by side effects including involuntary abnormal movements, termed dyskinesia 1. Here, a protocol for MALDI imaging mass spectrometry is presented that detects changes in rat brain neuropeptide levels related to dyskinesia.

Difficulty
advanced
Total time
~3–4 days (tissue preparation, matrix application, MS acquisition, and data processing per sample)
Model organism
Rat (Parkinsonian model with L-DOPA-induced dyskinesia)
Biosafety
BSL-1

Steps

1
Prepare and mount brain tissue sections

Harvest brain tissue, section using cryostat or microtome, and mount on conductive MALDI target plates. Ensure sections are thin and uniformly adhered for optimal imaging.

▶ 02:02
2
Apply MALDI matrix to tissue sections

Deposit uniform matrix coating (typically α-cyano-4-hydroxycinnamic acid or other neuropeptide-compatible matrix) onto mounted tissue using spray or sublimation methods to enable ionization.

▶ 03:40
3
Acquire and process MALDI mass spectrometry data

Perform raster scanning of tissue sections using MALDI-TOF or MALDI-Orbitrap instrumentation, collect mass spectra across regions of interest, and process data to generate spatial neuropeptide distribution maps.

▶ 05:24
4
Validate detected neuropeptides by complementary analysis

Confirm MALDI-detected neuropeptide identities using liquid chromatography-mass spectrometry (LC-MS), immunohistochemistry, or tandem MS fragmentation analysis.

▶ 12:29
5
Interpret neuropeptide distribution patterns in disease

Compare spatial neuropeptide maps between control and L-DOPA-treated dyskinetic rat brains to identify alterations in specific brain regions associated with motor dysfunction.

▶ 14:18
💬 Comments coming soon