News & Views in 2024

Astrocytes have important roles in disease and are difficult to modulate, owing to a paucity of known targets. Clayton et al. develop a screening platform to unbiasedly identify modulators of astrocyte reactivity. They discover that HDAC3 inhibitors regulate astrocyte transitions into their reactive phenotype in vitro and in vivo.

The Sehgal lab presents data showing that the non-cell autonomous pathway of glial lipid droplet formation occurs during sleep and helps to resolve neuronal reactive oxygen species (ROS). This promotes neuronal function after an active day. Hence, this pathway has an important physiological function beyond its previously described role in ROS-associated diseases, including Alzheimer’s disease.

Both caloric restriction and obesity affect autoimmune diseases. The activation of brainstem neurons in the ventrolateral medulla (VLM) with fasting suppresses experimental autoimmune diseases. Stimulation of VLM neurons alters T cell traffic by redistributing immune cells to bone marrow and reduces inflammatory cytokine production, thus providing therapy of experimental autoimmunity.

Muller et al. demonstrate that reward signals recorded from the frontal cortex of nonhuman primates exhibit a population-based scheme for learning probability distributions over reward values. This study provides evidence that neural signals outside of the midbrain reflect the principles of distributional reinforcement-learning theory.