A novel SPECT-based approach reveals early mechanisms of central and peripheral inflammation after cerebral ischemia

J Cereb Blood Flow Metab. 2015 Dec;35(12):1921-9. doi: 10.1038/jcbfm.2015.174. Epub 2015 Jul 29.

Abstract

Inflammation that develops in the brain and peripheral organs after stroke contributes profoundly to poor outcome of patients. However, mechanisms through which inflammation impacts on brain injury and overall outcome are improperly understood, in part because the earliest inflammatory events after brain injury are not revealed by current imaging tools. Here, we show that single-photon emission computed tomography (NanoSPECT/CT Plus) allows visualization of blood brain barrier (BBB) injury after experimental stroke well before changes can be detected with magnetic resonance imaging (MRI). Early 99mTc-DTPA (diethylene triamine pentaacetic acid) signal changes predict infarct development and systemic inflammation preceding experimental stroke leads to very early perfusion deficits and increased BBB injury within 2 hours after the onset of ischemia. Acute brain injury also leads to peripheral inflammation and immunosuppression, which contribute to poor outcome of stroke patients. The SPECT imaging revealed early (within 2 hours) changes in perfusion, barrier function and inflammation in the lungs and the gut after experimental stroke, with good predictive value for the development of histopathologic changes at later time points. Collectively, visualization of early inflammatory changes after stroke could open new translational research avenues to elucidate the interactions between central and peripheral inflammation and to evaluate in vivo 'multi-system' effects of putative anti-inflammatory treatments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood-Brain Barrier / diagnostic imaging
  • Blood-Brain Barrier / pathology
  • Brain Ischemia / diagnostic imaging*
  • Brain Ischemia / pathology
  • Gastrointestinal Tract / pathology
  • Image Processing, Computer-Assisted
  • Immunosuppression Therapy
  • Infarction, Middle Cerebral Artery / diagnostic imaging
  • Infarction, Middle Cerebral Artery / pathology
  • Inflammation / diagnostic imaging*
  • Inflammation / pathology
  • Lung / pathology
  • Magnetic Resonance Imaging
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Nervous System Diseases / etiology
  • Nervous System Diseases / psychology
  • Radiopharmaceuticals
  • Stroke / diagnostic imaging
  • Stroke / pathology
  • Technetium Tc 99m Pentetate
  • Tomography, Emission-Computed, Single-Photon / methods*

Substances

  • Radiopharmaceuticals
  • Technetium Tc 99m Pentetate