Evolution of microglial activation in ischaemic core and peri-infarct regions after stroke: a PET study with the TSPO molecular imaging biomarker [((11))C]vinpocetine.

Abstract

Although there is increasing evidence for microglial activation after an ischaemic stroke in the infarct core and the peri-infarct region, the "evolution" of the process in stroke patients is poorly known. Using PET and [((11))C]vinpocetine, we measured the regional changes of TSPO in the brain of nine ischaemic stroke patients up to 14weeks after the insult. Already a week after stroke there was an increased radioligand uptake, indicating the up-regulation of TSPO and the presence of activated microglia, in both the ischaemic core and the peri-infarct zone. This increased activation showed a steady decrease with post stroke time. The proportion between %SUV values in the peri-infarct zone and the ischaemic core increased with time. There were no time-dependent TSPO activity changes in other regions, not affected directly by the stroke. The present observations demonstrate that increased regional microglia activation, as a consequence of stroke, can be visualised with PET, using the TSPO molecular imaging biomarker [((11))C]vinpocetine. The evolution of this microglial activation shows a time dependent decrease the gradient of which is different between the peri-infarct zone and the ischaemic core. The findings indicate an increased microglial activation in the peri-stroke region for several weeks after the insult.

• Authors: Balázs Gulyás, Miklós Tóth, Martin Schain, Anu Airaksinen, Adám Vas, Konstantinos Kostulas, Per Lindström, Jan Hillert, Christer Halldin
• Journal: Journal of the neurological sciences (J Neurol Sci) Vol. 320 Issue 1-2 Pg. 110-7 (Sep 15 2012) ISSN: 1878-5883 [Electronic] Netherlands
• PMID: 22841414 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 Elsevier B.V. All rights reserved.

Chemical References

• Biomarkers
• Carbon Radioisotopes
• Receptors, GABA
• TSPO protein, human
• Vinca Alkaloids
• vinpocetine

Topics

• Adult
• Aged
• Biomarkers (metabolism)
• Brain Ischemia (complications, diagnostic imaging, metabolism, pathology)
• Carbon Radioisotopes
• Functional Neuroimaging (methods, statistics & numerical data)
• Humans
• Infarction (complications, diagnostic imaging, metabolism, pathology)
• Magnetic Resonance Imaging (methods, statistics & numerical data)
• Male
• Microglia (diagnostic imaging, metabolism)
• Middle Aged
• Molecular Imaging (methods, statistics & numerical data)
• Organ Size
• Positron-Emission Tomography (methods, statistics & numerical data)
• Radioligand Assay (methods, statistics & numerical data)
• Receptors, GABA (metabolism)
• Stroke (complications, diagnostic imaging, metabolism, pathology)
• Time Factors
• Up-Regulation
• Vinca Alkaloids