Ischemic Stroke Causes Disruptions in the Carnitine Shuttle System

Area of Science:

• Neuroscience
• Metabolomics
• Biochemistry

Background:

• Ischemic stroke causes cellular energy imbalance due to glucose deprivation.
• Acylcarnitines are crucial for fatty acid transport into mitochondria for energy production via beta-oxidation.
• Traditional bulk analysis lacks spatial resolution for metabolite distribution in tissues.

Purpose of the Study:

• To investigate the spatial distribution and quantification of acylcarnitines in stroke-affected brain tissue.
• To understand the impact of ischemia on energy metabolism and the carnitine shuttle system.
• To utilize quantitative mass spectrometry imaging for unbiased molecular analysis.

Main Methods:

• Pneumatically assisted nanospray desorption electrospray ionization mass spectrometry imaging (PA nano-DESI MSI) was employed.
• Internal standards were used for quantitative imaging and accurate annotation of acylcarnitines.
• Fragmentation patterns were analyzed to identify endogenous acylcarnitines.

Main Results:

• Significant accumulation of long-chain acylcarnitines was observed in the ischemic brain tissue of the middle cerebral artery occlusion (MCAO) model.
• Disruptions in the carnitine shuttle system were demonstrated, affecting mitochondrial beta-oxidation.
• Quantitative imaging revealed regional differences in metabolite concentrations.

Conclusions:

• Quantitative monitoring of metabolite distributions is vital for understanding cellular compensation mechanisms after stroke.
• Ischemia-induced alterations in acylcarnitine metabolism impact energy production pathways.
• PA nano-DESI MSI provides valuable insights into the spatial biochemistry of stroke.