The impact of adult neurogenesis on affective functions: of mice and men.

In most mammals, new neurons are not only produced during embryogenesis but also after birth. Soon after adult neurogenesis was discovered, the influence of recruiting new neurons on cognitive functions, especially on memory, was documented. Likewise, the late process of neuronal production also contributes to affective functions, but this outcome was recognized with more difficulty.

Inhibition of the replication of SARS-CoV-2 in human cells by the FDA-approved drug chlorpromazine.

Introduction: Urgent action is needed to fight the ongoing coronavirus disease 2019 (COVID-19) pandemic by reducing the number of infected cases, contagiousness and severity. Chlorpromazine (CPZ), an antipsychotic from the phenothiazine group, is known to inhibit clathrin-mediated endocytosis and has antiviral activity against severe acute respiratory syndrome coronavirus-1 (SARS-CoV-1) and Middle East respiratory syndrome coronavirus. The aim of this in-vitro study was to test CPZ against SARS-CoV-2 in monkey and human cells.

The next psychoactive drugs: From imipramine to ketamine.

Since the 1950s, the therapeutic arsenal against depression has grown considerably. From the discovery of mono-amine oxidase inhibitors (MAOIs) to the antidepressant effect of ketamine, several pharmacological breakthroughs made the history of psychiatry. These discoveries oriented the research about the pathophysiology of depression, which is one of the most disabling diseases worldwide affecting 10 to 20% of general population.

Microglial production of quinolinic acid as a target and a biomarker of the antidepressant effect of ketamine.

Major depressive disorder is a complex multifactorial condition with a so far poorly characterized underlying pathophysiology. Consequently, the available treatments are far from satisfactory as it is estimated that up to 30% of patients are resistant to conventional treatment. Recent comprehensive evidence has been accumulated which suggests that inflammation may be implied in the etiology of this disease.

The association of β-arrestin2 polymorphisms with response to antidepressant treatment in depressed patients.

The study of genetic polymorphisms involved in antidepressants (AD) response is essential to provide a personalized medicine approach in the field of depression. β-arrestin 2 (ARRB2) is a candidate gene in the pharmacogenetics of AD as it is involved in the signaling cascade downstream of numerous neurotransmitter receptors. We investigated the association between five ARRB2 single nucleotide polymorphisms (SNPs): rs1045280, rs2036657, rs4790694, rs3786047 and rs452246, and response to AD treatment in a sample of 569 patients with a major depressive episode treated for 6months.

No impact of eight NTRK2 genetic polymorphisms on 6-month antidepressant efficacy in depressed patients.

Aim: NTRK2 is the main receptor of the brain derived neurotrophic factor, which is involved in antidepressant efficacy. We assessed the impact of eight NTRK2 SNPs pertaining to response and remission after antidepressant treatment in depressed patients.

Patients & Methods: In a naturalistic study, 569 patients with a major depressive episode requiring a new antidepressant treatment were genotyped for eight NTRK2 SNPs (rs1187352, rs1439050, rs1778933 rs2289656, rs2289657, rs2289658, rs3824519, rs56142442) and prospectively assessed for response and remission after 6 months of treatment.

Mother's Emotional and Posttraumatic Reactions after a Preterm Birth: The Mother-Infant Interaction Is at Stake 12 Months after Birth.

Objectives: Very preterm infants are known to be at risk of developmental disabilities and behavioural disorders. This condition is supposed to alter mother-infant interactions. Here we hypothesize that the parental coping with the very preterm birth may greatly influence mother-infant interactions.

Brain-derived neurotrophic factor Val66Met polymorphism and 6-month antidepressant remission in depressed Caucasian patients.

Background: Whether the Brain Derived Neurotrophic Factor (BDNF) Val66Met polymorphism can predict antidepressant drug efficacy in depressed patients remains unclear, suggesting that it may depend on antidepressant classes. We assessed the impact of Val66Met polymorphism on antidepressant response and remission depending on antidepressant classes.

Methods: In a 6-month prospective, real-world setting, treatment study, 345 Caucasian depressed patients requiring a new or different drug treatment with a selective serotonin reuptake inhibitor (SSRI), a serotonin and noradrenalin reuptake inhibitor (SNRI) or a tricyclic antidepressant (TCA), were genotyped and assessed for response and remission.

Converging translational evidence for the involvement of the serotonin 2A receptor gene in major depressive disorder.

An association between serotonin 2A receptor (5-HT2AR), encoded by HTR2A gene, and major depressive disorder (MDD) has been suggested. Here, we combined preclinical and ecological clinical approaches to explore the impact of impaired 5-HT2AR-mediated transmission on MDD or anxio-depressive-like phenotype in mice. Htr2a knock-out mice (Htr2a(-/-)) and wild-type mice were compared for the ability of chronic corticosterone to elicit some anxio-depressive-like phenotype in three behavioral paradigms (elevated plus maze, tail suspension test and splash test).

Preparation and delivery of 4-hydroxy-tamoxifen for clonal and polyclonal labeling of cells of the surface ectoderm, skin, and hair follicle.

To study the cell behavior during morphogenesis of mouse surface ectoderm, skin, and hair follicles, we (1-3) have developed a new method to temporally induce clones that is based on a tamoxifen-dependent Cre recombinase. The classical protocol consisting in dissolving 4-hydroxy-tamoxifen or tamoxifen in corn oil to perform intraperitoneal (ip) injections (4) is not optimal to control the pharmacokinetic parameters of the induction as it leads to experimental variability in terms of timing and level of induction. We have developed a new protocol that consists in solubilizing 4-OHT or tamoxifen in an aqueous solvent using Cremophor(®) EL (5).

Large-scale clonal analysis reveals unexpected complexity in surface ectoderm morphogenesis.

Background: Understanding the series of morphogenetic processes that underlie the making of embryo structures is a highly topical issue in developmental biology, essential for interpreting the massive molecular data currently available. In mouse embryo, long-term in vivo analysis of cell behaviours and movements is difficult because of the development in utero and the impossibility of long-term culture.

Methodology/principal Findings: We improved and combined two genetic methods of clonal analysis that together make practicable large-scale production of labelled clones.

Methods in clonal analysis and applications.

During development, embryonic cells display a large variety of behaviors that lead to the formation of embryonic structures that are frequently transient. Simultaneously, cells progress towards a specific fate. The current challenge for embryologists is to resolve how these two distinct aspects of development co-exist.

Synchronised cycling gene oscillations in presomitic mesoderm cells require cell-cell contact.

Segmentation of the vertebrate body axis is initiated early in development with the sequential formation of somites. Somitogenesis is temporally regulated by a molecular oscillator, the segmentation clock, which acts within presomitic mesoderm (PSM) cells to drive periodic expression of the cyclic genes. We have investigated the kinetics of the progression of cycling gene expression along the PSM.