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Gallego-Landin, I.

Publications and source records attributed to Gallego-Landin, I..

4 recordsLinked to original sources

The FAAH inhibitor URB597 reduces cocaine seeking during conditioned punishment and withdrawal

The endocannabinoid system is prominently implicated in the control of cocaine reinforcement due to its relevant role in synaptic plasticity and neurotransmitter modulation in the mesocorticolimbic system. The inhibition of fatty acid amide hydrolase (FAAH), and the resulting increase in anandamide and other N-acylethanolamines, represents a promising strategy for reducing drug seeking. In the present study, we aimed to assess the effects of the FAAH inhibitor URB597 (1 mg/kg) on crucial features of cocaine addictive-like behaviour in mice. Therefore, we tested the effects of URB597 on acquisition of cocaine (0.6 mg/kg/inf) self-administration, compulsive-like cocaine intake and cue-induced drug-seeking behaviour during withdrawal. URB597 reduced cocaine intake under conditioned punishment while having no impact on acquisition. This result was associated to increased cannabinoid receptor 1 gene expression in the ventral striatum and medium spiny neurons activation in the nucleus accumbens shell. Moreover, URB597 reduced cue-induced drug-seeking behaviour during prolonged abstinence and prevented the withdrawal-induced increase in FAAH gene expression in the ventral striatum. In this case, URB597 decreased activation of medium spiny neurons in the nucleus accumbens core. Our findings evidence the prominent role of endocannabinoids in the development of cocaine addictive-like behaviours and support the potential of FAAH inhibition as a therapeutical target for the treatment of cocaine addiction.

neuroscience↗

PPAR-γ is a promising therapeutic target for memory deficits induced by early alcohol exposure.

BackgroundPatients diagnosed with fetal alcohol spectrum disorder (FASD) show persistent cognitive disabilities, including memory deficits. However, the neurobiological substrates of these deficits remain unclear. Here, we studied the participation of the expanded endocannabinoid system (ECS), which is known to be affected by alcohol in other life periods, and it is involved in memory impairments of neurodevelopmental disorders. MethodsC57BL/6 female mice were exposed to a time-limited access to either water or alcohol to model prenatal and lactation alcohol exposure (PLAE). The expanded ECS was analyzed in the prefrontal cortex and the hippocampus of the offspring at post-partum day (PD) 25 and 70. Then, memory performance was tested after the repeated administration (from PD25 to PD34) of: i) URB597, to increase N-acylethanolamines (NAEs), and GW9662, a peroxisome proliferator-activated receptor gamma (PPAR-{gamma}) antagonist; ii) pioglitazone, a PPAR-{gamma} agonist. Finally, we used a viral approach to upregulate astrocytic PPAR-{gamma} in the hippocampus to restore memory deficits. ResultsWe report that PLAE causes a hippocampal reduction of NAEs and PPAR-{gamma} at PD25. Moreover, URB597 suppresses PLAE-induced memory deficits through PPAR-{gamma}, since its effects are prevented by GW9662. Direct PPAR-{gamma} activation, using pioglitazone, also ameliorates memory impairments. Lastly, we demonstrate that the upregulation of PPAR-{gamma} in hippocampal astrocytes is sufficient to rescue PLAE-induced memory deficits. ConclusionOur data reveal a bidirectional link between memory deficits and expanded ECS alterations in the context of early alcohol exposure. Furthermore, we proved that PPAR-{gamma} in hippocampal astrocytes represents a specific therapeutic target for memory deficits in FASD.

neuroscience↗

A novel mouse model of postpartum depression and the neurobiological effects of fast-acting antidepressant treatments

postpartum depression (PPD) is a severe psychiatric disorder that affects up to 15% of mothers and impairs mother-infant bonding with devastating consequences on the child development and the mother health. Several studies indicate a possible dysregulation of glutamatergic and GABAergic signalling in the corticolimbic system, as well as a downregulation of the allopregnanolone levels in serum of PPD patients. Although brexanolone, an allopregnanolone-based treatment, has recently emerged as fundamental PPD treatment, there is scarce evidence on its neurobiological action mechanism. Moreover, ketamine appears to be a promising antidepressant treatment preventing PPD, nevertheless whether it might be a more effective than allopregnanolone for some patients remain unknown. Therefore, the present study is aimed to evaluate the depressive-like phenotype of postpartum females undergoing maternal separation with early weaning (MSEW) protocol, as well as to compare the effectiveness of ketamine and allopregnanolone treatments. MSEW dams show increased despair-like behaviour, anhedonia and disrupted maternal behaviour. Moreover, lower allopregnanolone serum levels, reduction of vesicular transporters for GABA (VGAT) and glutamate (VGLUT1) in the infralimbic cortex, as well as decreased hippocampal cellular proliferation are found in MSEW females. As for the antidepressant treatments, both drugs prevent despair-like behaviour, whereas only ketamine reverts anhedonia present in MSEW females. In addition, both treatments induce pro-neurogenic effects in the dorsal hippocampus but only allopregnanolone increases the VGAT and VGLUT1, without altering the excitatory/inhibitory ratio. Altogether, we propose a new mice model that recapitulates the core symptomatology and alterations in glutamatergic and GABAergic systems shown in PPD patients, which allows us to investigate the therapeutic mechanisms of allopregnanolone and ketamine.

neuroscience↗

Bmal1-knockout mice exhibit reduced cocaine-seeking behaviour and cognitive impairments

Brain and Muscle Arnt-like Protein 1 (BMAL1) is an essential component of the molecular clock underlying circadian rhythmicity. Recently, its function has also been associated with alterations in mood, and reward processing. We investigated the behavioural and neurobiological impact of Bmal1 gene deletion in mice, as well as how these alterations affect rewarding effects of cocaine. Additionally, key clock genes and components of the dopamine system were assessed in several brain areas. Our results evidence behavioural alterations in Bmal1-KO mice including changes in locomotor activity with impaired habituation to environments as well as short term memory and social recognition impairments. In addition, Bmal1-KO mice experienced reduced cocaine-induced sensitization and rewarding effects of cocaine as well as reduced cocaine-seeking behaviour. Furthermore, Bmal1 deletion influenced the expression of other clock-related genes in the mPFC and striatum as well as alterations in the expression of dopaminergic elements. Overall, the present article offers a novel and extensive characterization of Bmal1-KO animals. We suggest that reduced cocaines rewarding effects in these mutant mice might be related to Bmal1 role as an expression regulator of MAO and TH, two essential enzymes involved in dopamine metabolism.

neuroscience↗