Dataset Information

GABA interneurons mediate the rapid antidepressant-like effects of scopolamine.

ABSTRACT: Major depressive disorder (MDD) is a recurring psychiatric illness that causes substantial health and socioeconomic burdens. Clinical reports have revealed that scopolamine, a nonselective muscarinic acetylcholine receptor antagonist, produces rapid antidepressant effects in individuals with MDD. Preclinical models suggest that these rapid antidepressant effects can be recapitulated with blockade of M1-type muscarinic acetylcholine receptors (M1-AChR); however, the cellular mechanisms underlying activity-dependent synaptic and behavioral responses to scopolamine have not been determined. Here, we demonstrate that the antidepressant-like effects of scopolamine are mediated by GABA interneurons in the medial prefrontal cortex (mPFC). Both GABAergic (GAD67+) interneurons and glutamatergic (CaMKII+) interneurons in the mPFC expressed M1-AChR. In mice, viral-mediated knockdown of M1-AChR specifically in GABAergic neurons, but not glutamatergic neurons, in the mPFC attenuated the antidepressant-like effects of scopolamine. Immunohistology and electrophysiology showed that somatostatin (SST) interneurons in the mPFC express M1-AChR at higher levels than parvalbumin interneurons. Moreover, knockdown of M1-AChR in SST interneurons in the mPFC demonstrated that M1-AChR expression in these neurons is required for the rapid antidepressant-like effects of scopolamine. These data indicate that SST interneurons in the mPFC are a promising pharmacological target for developing rapid-acting antidepressant therapies.

SUBMITTER: Wohleb ES

PROVIDER: S-EPMC4922686 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

GABA interneurons mediate the rapid antidepressant-like effects of scopolamine.

Wohleb Eric S ES Wu Min M Gerhard Danielle M DM Taylor Seth R SR Picciotto Marina R MR Alreja Meenakshi M Duman Ronald S RS

The Journal of clinical investigation 20160606 7

Major depressive disorder (MDD) is a recurring psychiatric illness that causes substantial health and socioeconomic burdens. Clinical reports have revealed that scopolamine, a nonselective muscarinic acetylcholine receptor antagonist, produces rapid antidepressant effects in individuals with MDD. Preclinical models suggest that these rapid antidepressant effects can be recapitulated with blockade of M1-type muscarinic acetylcholine receptors (M1-AChR); however, the cellular mechanisms underlying ...[more]

PMID: 27270172

Similar Datasets

Project description:BACKGROUND:Brain-derived neurotrophic factor (BDNF) plays a key role in the pathophysiology and treatment of depression. Recent clinical studies demonstrate that scopolamine, a nonselective muscarinic acetylcholine receptor antagonist, produces rapid antidepressant effects in patients with depression. Rodent studies demonstrate that scopolamine increases glutamate transmission and synaptogenesis in the medial prefrontal cortex (mPFC). Here we tested the hypothesis that activity-dependent BDNF release within the mPFC is necessary for the antidepressant actions of scopolamine. METHODS:Behavioral effects of scopolamine were assessed in BDNF Val/Met knock-in mice, in which BDNF processing and release are impaired. In addition, intra-mPFC infusion of a BDNF-neutralizing antibody was performed to test the necessity of BDNF release in driving scopolamine-induced behavioral responses. Further in vivo and in vitro experiments were performed to delineate BDNF-dependent mechanisms underlying the effects of scopolamine. RESULTS:We found that BDNF Met/Met mice have attenuated responses to scopolamine and that anti-BDNF antibody infusions into the mPFC prevented the antidepressant-like behavioral effects of scopolamine. In vitro experiments show that scopolamine rapidly stimulates BDNF release and tropomyosin receptor kinase B-extracellular signal-regulated kinase signaling. Moreover, these effects require alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor activation and are blocked by neuronal silencing. Importantly, pretreatment with verapamil prevented scopolamine-induced behavioral responses and BDNF-tropomyosin receptor kinase B signaling, suggesting that these effects are dependent on activation of voltage-dependent calcium channels. CONCLUSIONS:The results identify an essential role for activity-dependent BDNF release in the rapid antidepressant effects of scopolamine. Attenuation of responses in BDNF Met mice indicates that patients with the Met allele may be less responsive to scopolamine.

Project description:Although regulation of energy metabolism has been linked with multiple disorders, its role in depression and responsiveness to antidepressants is less-known. We found that an epigenetic and energetic agent, acetyl-L-carnitine (LAC, oral administration), rapidly rescued the depressive- and central and systemic metabolic-like phenotype of LAC-deficient Flinders Sensitive Line (FSL) rats. After acute stress during LAC treatment, a subset of FSL continued to respond to LAC (rFSL), whereas the other subset did not respond (nrFSL). RNAseq for the ventral dentate-gyrus (vDG), a mood-regulatory region, identified metabolic factors as key markers predisposing to depression (insulin receptors Insr, glucose transporters Glut-4 and Glut-12, the regulator of appetite Cartpt) and to LAC responsiveness (leptin receptors Lepr, metabotropic glutamate receptors-2 mGlu2, neuropeptide-Y NPY, and mineralocorticoid receptors MR). Furthermore, we found that stress-induced treatment-resistance in nrFSL shows a new gene profile, including the metabolic regulator factors Elovl7 and Cyb5r2 and the synaptic regulator NPAS4. Finally, while improving central energy regulation and exerting rapid antidepressant-like effects, LAC corrected a systemic hyperinsulinemia and hyperglycemia.tance in rFSL and failed to do that in nrFSL. These findings establish CNS energy regulation as factor to be considered for the development of better therapeutics. Agents, like LAC, which regulate metabolic factors and reduce glutamate overflow, could rapidly ameliorate depression and could also be considered for treatment of insulin-resistance in depressed subjects. The approach here serves as a model for identifying markers and underlying mechanisms of predisposition to diseases and treatment responsiveness that may be useful in translation to human behavior and psychopathology. Ventral dentate gyrus RNA from 3 biological replicates per group (vehicle-FRL, vehicle-FSL, LAC-treated not-responder FSL, LAC-treated responder FSL, all males) was used for library prep (TruSeq Stranded Total RNA with Ribo-Zero Human/Mouse/Rat) and sequenced on Illumina HiSeq2500 at the Genomic Core facility at The Rockefeller University. Each sample was provided with a unique adapter and all samples were put in the same pool and run in multiple lanes to control for lane effects with a sequencing depth of about 30M (100bp, single).

Dataset Information

GABA interneurons mediate the rapid antidepressant-like effects of scopolamine.

Publications

GABA interneurons mediate the rapid antidepressant-like effects of scopolamine.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets