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Willoughby, D.

Publications and source records attributed to Willoughby, D..

2 recordsLinked to original sources

Dopamine Activates Astrocytes in Prefrontal Cortex via α1-Adrenergic Receptors

The prefrontal cortex (PFC) is a hub for cognitive control, and dopamine profoundly influences its functions. In other brain regions, astrocytes sense diverse neurotransmitters and neuromodulators and, in turn, orchestrate regulation of neuroactive substances. However, basic physiology of PFC astrocytes, including which neuromodulatory signals they respond to and how they contribute to PFC function, is lacking. Here, we characterize divergent signaling signatures in astrocytes of PFC and primary sensory cortex in mice, which are linked to differential responsivity to locomotion. We find that PFC astrocytes express receptors for dopamine, but are unresponsive through the Gs/Gi-cAMP pathway. Instead, fast calcium signals in PFC astrocytes are time-locked to dopamine release, and are mediated by 1-adrenergic receptors both ex vivo and in vivo. Further, we describe dopamine-triggered regulation of extracellular ATP at PFC astrocyte territories. Thus, we identify astrocytes as active players in dopaminergic signaling in PFC, contributing to PFC function though neuromodulator receptor crosstalk. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=195 SRC="FIGDIR/small/500710v1_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@e71858org.highwire.dtl.DTLVardef@1ef506forg.highwire.dtl.DTLVardef@89e4edorg.highwire.dtl.DTLVardef@11483e1_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Exercise conditioned plasma dampens inflammation via clusterin and boosts memory

Physical exercise seems universally beneficial to human and animal health, slowing cognitive aging and neurodegeneration. Cognitive benefits are tied to increased plasticity and reduced inflammation within the hippocampus, yet little is known about the factors and mechanisms mediating these effects. We discovered \"runner\" plasma, collected from voluntarily running mice, infused into sedentary mice recapitulates the cellular and functional benefits of exercise on the brain. Importantly, runner plasma reduces baseline neuroinflammatory gene expression and prominently suppresses experimentally induced brain inflammation. Plasma proteomic analysis shows a striking increase in complement cascade inhibitors including clusterin, which is necessary for the anti-inflammatory effects of runner plasma. Cognitively impaired patients participating in structured exercise for 6 months showed higher plasma clusterin levels, which correlated positively with improvements in endurance and aerobic capacity. These findings demonstrate the existence of anti-inflammatory \"exercise factors\" that are transferrable, benefit the brain, and are present in humans engaging in exercise.

neuroscience↗