In an innovative study, researchers at the UMH-CSIC Institute of Neuroscience have devised a non-invasive innovative approach to imaging the activation of microglia and astrocytes in the gray matter of the brain using MRI-weighted MRI. dissemination (dw-MRI), according to a press release from the institution published on Friday. The development may have applications in Alzheimer’s and other dementias, Parkinson’s and multiple sclerosis.
The first sign of this type of MRI
“This is the first time that it has been shown that the MRI signal can detect the activation of microglia and astrocytes, with specific footprints for each cell population. This strategy we have used reflects post-mortem validation morphological changes by quantitative immunohistochemistry, “said Dr. Silvia de Santis and Dra. Santiago Canals, both from the UMH-CSIC Institute of Neuroscience.
The previous gold standard for in vivo brain inflammation imaging was positron emission tomography (PET). However, this process was difficult to generalize and was associated with exposure to ionizing radiation.
Therefore, it was reserved for use in vulnerable populations and in longitudinal studies. On the other hand, diffusion-weighted MRI has the unique ability to imagine the microstructure of the brain in vivo in a non-invasive and high-resolution way by capturing the random movement of water molecules in the brain parenchyma to generate contrast in images of MRI.
A cohort of healthy humans in high resolution
The new approach was tested in a high-resolution cohort of healthy humans, “in which we performed a reproducibility analysis. The significant association with known microglia density patterns in the human brain supports the usefulness of the method for We believe that characterizing, using this technique, relevant aspects of tissue microstructure during inflammation, non-invasively and longitudinally, can have a huge impact on our understanding of the pathophysiology of many brain conditions and can transforming current diagnostic practice and treatment follow-up strategies for neurodegenerative diseases “. added Silvia de Santis.
In addition, the technique has been found to be sensitive and specific for detecting inflammation with and without neurodegeneration so that both conditions can be differentiated. It also discriminates between the inflammatory and demyelinating characteristics of multiple sclerosis.
To validate the model, the researchers used an established rat inflammation paradigm based on intracerebral lipopolysaccharide (LPS) administration, as well as an established demyelination paradigm, based on focal lysolecithin administration, to show that developed biomarkers do not reflect the model. tissue alterations that are frequently found in brain disorders.
The new method can revolutionize the treatment of neurodegenerative diseases. The study is published in the journal Science Advances.
Summary:
Although glia is increasingly involved in the pathophysiology of psychiatric and neurodegenerative disorders, the methods available for imaging these cells in vivo involve invasive procedures or positron emission tomography radiographs, which offer a resolution and low specificity. Here, we present a non-invasive diffusion-weighted magnetic resonance imaging (MRI) method for imaging changes in glia morphology. Using rat models of neuroinflammation, degeneration, and demyelination, we demonstrate that diffusion-weighted MRI carries a fingerprint of microglia and astrocyte activation and that population-specific signatures can be quantified noninvasively. The method is sensitive to changes in glia morphology and proliferation, providing a quantitative account of neuroinflammation, regardless of the existence of concomitant neuronal loss or demyelinating injury. We demonstrate the translational value of the approach by showing significant associations between MRI and histological markers of microglia in humans. This framework has the potential to transform basic and clinical research by clarifying the role of inflammation in health and disease.