Suppression of food restriction-evoked hyperactivity in activity-based anorexia animal model through glutamate transporters GLT-1 at excitatory synapses in the hippocampus.

Autor: Bilash OM; The Neuroscience Institute, NYU Langone Medical Center, New York, NY, USA.; Center for Neural Science, New York University, New York, NY, USA., Actor-Engel HS; Center for Neural Science, New York University, New York, NY, USA., Sherpa AD; Center for Neural Science, New York University, New York, NY, USA., Chen YW; Center for Neural Science, New York University, New York, NY, USA., Aoki C; The Neuroscience Institute, NYU Langone Medical Center, New York, NY, USA.; Center for Neural Science, New York University, New York, NY, USA.
Jazyk: angličtina
Zdroj: Synapse (New York, N.Y.) [Synapse] 2021 Jul; Vol. 75 (7), pp. e22197. Date of Electronic Publication: 2021 Mar 16.
DOI: 10.1002/syn.22197
Abstrakt: Severe voluntary food restriction is the defining symptom of anorexia nervosa (AN), but anxiety and excessive exercise are maladaptive symptoms that contribute significantly to the severity of AN and which individuals with AN have difficulty suppressing. We hypothesized that the excitability of hippocampal pyramidal neurons, known to contribute to anxiety, leads to the maladaptive behavior of excessive exercise. Conversely, since glutamate transporter GLT-1 dampens the excitability of hippocampal pyramidal neurons through the uptake of ambient glutamate and suppression of the GluN2B-subunit containing NMDA receptors (GluN2B-NMDARs), GLT-1 may contribute toward dampening excessive exercise. This hypothesis was tested using the mouse model of AN, called activity-based anorexia (ABA), whereby food restriction evokes the maladaptive behavior of excessive wheel running (food restriction-evoked running, FRER). We tested whether individual differences in ABA vulnerability of mice, quantified based on FRER, correlated with individual differences in the levels of GLT-1 at excitatory synapses of the hippocampus. Electron microscopic immunocytochemistry (EM-ICC) was used to quantify GLT-1 levels at the excitatory synapses of the hippocampus. The FRER seen in individual mice varied more than 10-fold, and Pearson correlation analyses revealed a strong negative correlation (p = .02) between FRER and GLT-1 levels at the axon terminals of excitatory synapses and at the surrounding astrocytic plasma membranes. Moreover, synaptic levels of GluN2B-NMDARs correlated strongly with GLT-1 levels at perisynaptic astrocytic plasma membranes. There is at present no accepted pharmacotherapy for AN, and little is known about the etiology of this deadly illness. Current findings suggest that drugs increasing GLT-1 expression may reduce AN severity through the reduction of GluN2B-NMDAR activity.
(© 2021 Wiley Periodicals, Inc.)
Databáze: MEDLINE
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