Invasion of phagocytic Galectin 3 expressing macrophages in the diabetic brain disrupts vascular repair.

The cellular events that dictate the repair of damaged vessels in the brain, especially in those with vascular risk factors such as diabetes, is poorly understood. Here, we dissected the role of resident microglia and infiltrative macrophages in determining the repair of ruptured cerebral microvessels. Using in vivo time-lapse imaging, gene expression analysis, and immunohistochemistry, we identified a unique population of phagocytic Galectin 3 (Gal3) expressing macrophages, distinct from resident microglia, which infiltrated and aggregated at the site of injury in diabetic mice and were associated with the elimination of microvessels.

Steady-State Free Ca in Astrocytes Is Decreased by Experience and Impacts Arteriole Tone.

Astrocytes can control basal synaptic strength and arteriole tone via their resting Ca activity. However, whether resting astrocyte Ca can adjust to a new steady-state level, with an impact on surrounding brain cells, remains unknown. Using two-photon Ca imaging in male rat acute brain slices of the somatosensory neocortex, we found that theta burst neural activity produced an unexpected long-lasting reduction in astrocyte free Ca in the soma and endfeet.