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Vyazovskiy, V.

Publications and source records attributed to Vyazovskiy, V..

2 recordsLinked to original sources

β2AR Agonists Sustain Thermogenesis and Leanness via Sympathofacilitation

Human thermogenesis depends on {beta}2-adrenoceptors ({beta}2AR) expressed in thermogenic adipocytes, which are activated by norepinephrine released from sympathetic neurons. Whether {beta}2AR also modulates thermogenesis via direct presynaptic action within sympathetic neurons has remained unclear. Here, we identify Adrb2 expression in human and rodent cervical sympathetic neurons. {beta}2AR agonism exerts neurotrophic effects and facilitates cholinergic responsiveness in mouse sympathetic neurons, indicating a sympathofacilitatory role. Selective deletion of {beta}2AR in sympathetic neurons leads to impaired nerve activity in brown adipose tissue, sympathetic neuropathy, worsened fasting-induced hypothermia, and progressive obesity in chow-fed mice--without changes in food intake. These findings uncover a presynaptic role for {beta}2AR in sustaining thermogenesis and regulating adiposity, suggesting sympathofacilitation as a therapeutic avenue for obesity. HighlightsO_LIHuman and mouse cervical sympathetic neurons express adrenoceptor beta 2 (Adrb2) C_LIO_LI{beta}2-adrenoceptor ({beta}2AR) activation is neurotrophic and facilitates sympathetic neuronal excitability C_LIO_LILoss of {beta}2AR in sympathetic neurons leads to neuropathy in brown adipose tissue and reduced sympathetic activity C_LIO_LIDeletion of {beta}2AR in sympathetic neurons exacerbates fasting-induced hypothermia and promotes obesity independently of food intake C_LI

physiology↗

Ablation of oligodendrogenesis in adult mice alters brain microstructure and activity independently of behavioural deficits

Oligodendrocytes continue to differentiate from their precursor cells even in adulthood, a process that can be modulated by neuronal activity and experience. Yet, our understanding of the functional role of adult oligodendrogenesis remains limited. Previous work has indicated that conditional ablation of oligodendrogenesis in adult mice can lead to learning and memory deficits in a range of behavioural tasks. Our results, reported here, have replicated a key finding that learning to run on a complex wheel with unevenly spaced rungs is disrupted by ablation of oligodendrogenesis. However, using ex vivo MRI (MTR and DTI), we also found that ablating oligodendrogenesis by itself alters brain microstructure, independent of behavioural experience. Furthermore, in vivo EEG recording in behaviourally naive mice with ablated oligodendrogenesis revealed altered brain activity in the form of increased EEG power density across a broad frequency range. Together, our data indicate that disrupting the formation of new oligodendrocytes directly alters brain microstructure and activity. This suggests a role for adult oligodendrogenesis in the maintenance of brain function and indicates that task-independent changes to brain structure and function might contribute to the learning and memory deficits associated with oligodendrogenesis ablation.

neuroscience↗