Near-Infrared-II Imaging Revealed Hypothermia Regulates Neuroinflammation Following Brain Injury by Increasing the Glymphatic Influx

Abstract

Advanced in vivo imaging techniques have facilitated the comprehensive visual exploration of animal biological processes, leading to groundbreaking discoveries such as the glymphatic system. However, current limitations of macroscopic imaging techniques impede the precise investigation of physiological parameters regulating this specialized lymphatic transport system. While NIR-II fluorescence imaging has demonstrated advantages in peripheral lymphatic imaging, there are few reports regarding its utilization in the glymphatic system. To address this, a noninvasive transcranial macroscopic NIR-II fluorescence imaging model is developed using a cyanine dye-protein coupled nanoprobe. NIR-II imaging with high temporal and spatial resolution reveals that hypothermia can increase the glymphatic influx by reducing the flow rate of cerebrospinal fluid. In addition, respiratory rate, respiratory amplitude, and heart rate all play a role in regulating the glymphatic influx. Thus, targeting the glymphatic influx may alter the trajectory of immune inflammation following brain injury, providing therapeutic prospects for treating brain injury with mild hypothermia.

Coupling Nanoscale Precision with Multiscale Imaging: A Multifunctional Near-Infrared Dye for the Brain

“…The development of fluorescent dyes targeting live cells has attracted extensive attention, such as membrane potentials and kinase activities. − Recently, NIR fluorescent molecules have been widely used in antibacterial research, cancer therapy, and biological detection and imaging. − NIR fluorescent molecules have enabled organelle-specific imaging and live imaging of cancer cells, zebrafish, and tumor-bearing mice. − Researchers reported a water-soluble plasma membrane (PM)-specific probe for PM imaging with excellent PM specificity and ultrafast staining capability . Another study reported a NIR aggregation-induced emission dye (AIE) for myelin imaging from nerve to brain tissues .…”