The determination of 18 metals and metalloids was realized in 4 tissues of 62 Stenella coeruleoalba specimens stranded along the French Mediterranean coastline from 2010 to 2016. While most concentrations were comparable to mean worldwide levels, Hg levels were alarming (1190 μg g-1 dw, in average). The results were discussed together with previous measurements in the same area, from 2002 to 2009. The elements Ni and Pb (-81 % and -88 % in liver in 2010-16 compared to 2002-09), and Cd (-40 % in kidney in 2010-16 compared to 2002-09) as well as V (-79 % in liver in 2013-16 compared to 2010-12), showed promising decreasing trends, and the decrease of Zn and Cu levels below baseline values could indicate a global decreasing burden of metal contaminants. In contrary, Hg dramatically increased in dolphins since 2007 (+135 % in liver in 2010-16 compared to 2002-09), regardless of total length. On the other hand, Se levels increased only slightly since 2012, potentially not offering anymore an efficient protection against Hg, with mean Se-to-Hg molar ratios below unity in most tissues (0.26, 0.56, 1.81, and 0.57 in liver, kidney, lung and muscle, respectively).

The value of hair in forensic toxicology has already been widely demonstrated. It offers a much wider detection window than other matrices, and its segmental analysis allows the documentation of a single, occasional or regular consumption of a large number of molecules. To date, considerable efforts are being made to achieve very high sensitivity using increasingly effective techniques in the forensic analysis of hair (gas chromatography with electron ionization - mass spectrometry (GC-EI/MS); gas chromatography with chemical ionization - mass spectrometry (GC-CI/MS); gas chromatography-tandem mass spectrometry (MS/MS); high or ultra performance liquid chromatography - tandem mass spectrometry (HPLC-MS/MS and UPLC-MS/MS)). Since the early 2000s, work has been carried out to analyze hair using matrix-assisted laser desorption/ionization (MALDI) coupled with imaging mass spectrometry (IMS). Intact, cut or pulverized, human head hairs are analyzed in all their forms. With a simplified and rapid sample preparation protocol, MALDI-IMS appears to be an attractive option for the forensic interpretation of hair analysis. The high spatial resolution clearly competes with conventional methods and strand segmentation. This article provides a complete overview on MALDI techniques used and its applications to better understand the pre-analytical and the analytical parts in the hair analysis.

There are few cetacean tissue-specific polycyclic aromatic hydrocarbon (PAH) concentration studies in the Mediterranean, despite this region is among the most subjected to chemical contamination. PAH analyses were conducted in different tissues of striped dolphins (Stenella coeruleoalba, N = 64) and bottlenose dolphins (Tursiops truncatus, N = 9) stranded along the French Mediterranean coastline from 2010 to 2016. Comparable levels were measured in S. coeruleoalba and T. trucantus (1020 and 981 ng g-1 lipid weight in blubber, 228 and 238 ng g-1 dry weight in muscle, respectively). The results suggested a slight effect of maternal transfer. The greatest levels were recorded by urban and industrial centers, and decreasing temporal trends were observed in males muscle and kidney, but not in other tissues. As a conclusion, the elevated levels measured could represent a serious threat to dolphins populations in this region, particularly by urban and industrial centers.

The hair has the unique capacity of "trapping" psychoactive substances within it. Thus, punctual or repeated drugs exposure can be revealed during hair analysis. Matrix assisted laser desorption ionization (MALDI) of single hair offers many advantages over conventional techniques such as liquid chromatography-tandem mass spectrometry (LC-MSMS): low amount of sample, simplified sample preparation and high spatial resolution of MALDI images (∼100 μm). We present a method to characterize and localize cocaine and its metabolites, the benzoylecgonine and cocaethylene in a single hair from two chronic abusers of drugs using MALDI-QIT-TOF (Quadrupole Ion Trap-Time of Flight) mass spectrometry coupled to imaging. Few hair of two regular cocaine and alcohol users, called patients A and B were decontaminated in successive water and dichloromethane baths, then oriented and cut longitudinally using a home-made cutting device. Uniform layers of α-cyano-4-hydroxycinnamic acid (CHCA) matrix were sprayed over the hair samples using an automatic and thermo-regulated sprayer (TM-Sprayer™, HTXImaging). Acquisitions in MS/MS mode were performed according to a raster adjusted at 80 μm using a MALDI-QIT-TOF instrument (Axima Resonance, Shimadzu). MS/MS images of two hair per patients were reconstituted using the BioMap® imaging software and then processed using the Quantinetix® software. The MALDI-MS/MS images highlight, over the last four months preceding the hair collection, a decrease in cocaine quantity for patient A, while an increase is observed for the patient B. Consumption profiles are compared with those obtained by liquid chromatography-tandem mass spectrometry, considered as the gold standard and the results are well correlated with those of the reference method. A manual procedure of hair longitudinal section is introduced. The results obtained after MALDI analysis are exploited as images in MS/MS mode and demonstrates cocaine use in the four months prior to collection for both drug users. In addition, the consumption profiles are comparable with those obtained by LC-MS/MS, confirming that the MALDI imaging is a method which efficiently characterize and map cocaine and its metabolites in single hair.

Gram-negative porins are the main entry for small hydrophilic molecules. We studied translocation of structurally related cephalosporins, ceftazidime (CAZ), cefotaxime (CTX) and cefepime (FEP). CAZ is highly active on E. coli producing OmpF (Outer membrane protein F) but less efficient on cells expressing OmpC (Outer membrane protein C), whereas FEP and CTX kill bacteria regardless of the porin expressed. This matches with the different capacity of CAZ and FEP to accumulate into bacterial cells as quantified by LC-MS/MS (Liquid Chromatography Tandem Mass Spectrometry). Furthermore, porin reconstitution into planar lipid bilayer and zero current assays suggest permeation of ≈1,000 molecules of CAZ per sec and per channel through OmpF versus ≈500 through OmpC. Here, the instant killing is directly correlated to internal drug concentration. We propose that the net negative charge of CAZ represents a key advantage for permeation through OmpF porins that are less cation-selective than OmpC. These data could explain the decreased susceptibility to some cephalosporins of enterobacteria that exclusively express OmpC porins.

Although banned for years, organochlorine pesticides and PCBs continue to affect aquatic life, dolphins being particularly exposed. The concentrations of 31 PCB congeners, and 15 banned pesticides or metabolites were measured in 5 tissues of 68 striped dolphins stranded in the Northwestern Mediterranean coast in 2010-16. The results were compared to historical data (1988-2009) and, even though there is a slow decreasing trend, the levels in the 2010-2016 samples were still elevated based on common cetacean toxicological thresholds. A transition period in 2007-08, probably caused by a morbillivirus epizootic amplified the stranding, espacially of highly contaminated specimens. From 2010, higher proportions in parent compounds towards metabolites were observed yet again. These changing patterns were likely reflect the exposure of dolphins to the remobilization of pollutants from contaminated soils and sediments, with a prominent role of rivers. This should lead to an even slower decline of these contaminants that could last for decades, requiring new efforts to reduce their dispersal to aquatic ecosystems.

Objectives. - Drugs exposure, whether it is punctual or repeated, can be revealed during the hair analysis. Matrix-assisted laser desorption/ionization (MALDI) of single hair offers many advantages over conventional techniques: simplified sample preparation, small amount of sample and high spatial resolution of images (similar to 100 mu m). The objective of this study is to develop a method to characterize and localize cocaine (COC), benzoylecgonine (BZE) and cocaethylene (CE) in a single hair using MALDI-QIT-TOF (Quadrupole Ion Trap-Time of Flight) mass spectrometry coupled to imaging. Methods. - Four hair of two regular cocaine and alcohol users (patients A and B) were decontaminated, oriented and cut longitudinally. The alpha-cyano-4-hydroxycinnamic acid (CHCA) matrix was sprayed over the sample using a thermo-regulated sprayer (TM-Sprayer (TM), HTXImaging). The MS/MS images were performed according to a raster at 80 mu m using a MALDI-QIT-TOF instrument (Axima Resonance, Shimadzu), then analyzed using the BioMap (R) imaging and Quantinetix (R) softwares. Results are compared with those obtained by liquid chromatography-tandem mass spectrometry (LC-MS/MS), considered as the gold standard [1]. Results and conclusion. - A procedure of hair longitudinal section is introduced. The results obtained after analysis are exploited as images. Analysis by MALDI-MS/MS demonstrates cocaine use in the four months prior to collection. In addition, the consumption profiles are comparable with those obtained by LC-MS/MS, confirming that the MALDI imaging is an efficient method to characterize and map cocaine and its metabolites in single hair. (C) 2019 Societe Francaise de Toxicologie Analytique. Published by Elsevier Masson SAS. All rights reserved.

In glioblastomas, apoptosis inhibitor proteins (IAPs) are involved in apoptotic and non-apoptotic processes. Here we used GDC-0152, a small molecule IAP inhibitor, to explore how IAPs participate in glioblastoma stem-like cell maintenance and fate under both hypoxic and normoxic environments. In hypoxia, IAPs inhibition triggered stem-like cells apoptosis and decreased proliferation in four human glioblastoma cell lines, whereas in normoxia it induced a loss of stemness and differentiation. In addition, we characterized a 3D glioblastoma spheroid model. By using MALDI images we validated that GDC-0152 penetrates in the entire sphere. TOF-SIMS analyses revealed an oxygen gradient correlated with spatial cellular heterogeneity with proliferative and apoptotic cells located close to the hypoxic core and GFAP+ cells at the periphery. Notably, Serine-Threonine Kinases activation analysis revealed that oxygen level affects signaling pathways activated by GDC-0152. In hypoxia, IAPs inhibition activated ATR whereas in normoxia it activated NF-κB. Our data brings new mechanistic insights revealing the dual role of IAPs inhibitors like GDC-0152 that are relevant to their therapeutic application in tumors like glioblastomas.

Présenter une méthode originale de caractérisation de la cocaïne (COC) et de ses métabolites (BZE, EME, COCE) dans un prélèvement capillaire par imagerie MALDI-MS2 et comparer les résultats à ceux obtenus dans le même prélèvement par MALDI-MS2 après déposition sur une plaque microarrays for mass spectrometry (MAMS, MAMS-MALDI-MS2) et par LC-MS2. Une mèche de cheveux orientée, prélevée sur une patiente consommatrice régulière de COC et d’alcool, est décontaminée par un mélange H20/CH2Cl2. Une dizaine de cheveux sont laissés intacts pour l’imagerie, le reste de la mèche est segmentée (4 × 1 cm) puis broyée. Imagerie MALDI : les cheveux non segmentés sont coupés longitudinalement, fixés sur une lame en verre conductrice et recouverts par une matrice acide α-cyano-4-hydroxycinnamique (CHCA) puis analysés par imagerie MALDI QIT-TOF-MS2 (Axima Resonance, Shimadzu). Les spectres obtenus (pas d’acquisition : 80 μm) sont retraités par le logiciel BioMap® et l’intensité du signal/unité de surface (1 cm) calculée par le logiciel Quantinetix®. MAMS-MALDI-MS2 : 1 mg de cheveux sont mis à incuber 2 h en présence des étalons internes deutérés. Après évaporation et reprise par ACN/H20, 3 μL de solution sont déposés sur une plaque MAMS et analysés en MALDI-TOF-MS2 (5800 TOF/TOF, SCIEX). Enfin, 50 mg de chaque segment sont analysés en LC-MS2 (3200 QTRAP, SCIEX) [1]. La quantification relative de la COC et des métabolites sur les segments étudiés en imagerie MALDI montre des profils comparables à ceux obtenus avec les 2 autres méthodes (Fig. 1). La technologie MALDI-MS2 démontre un fort potentiel dans la caractérisation de la cocaïne et ses métabolites, que ce soit à partir d’un cheveu unique (imagerie MALDI), ou d’une très faible quantité de cheveux broyés (1 mg) en MALDI-MS2 couplé à la technologie MAMS.

Démontrer le potentiel du MALDI couplé à la spectrométrie de masse (MS, MS2 et MS3) et à l’imagerie pour distinguer dans le cheveu trois isomères de la série JWH (JWH-007, JWH-019 et JWH-122) divergeant uniquement par la position d’un groupe méthyl. Les solutions standard de JWH-007, JWH-019 et JWH-122 ont été analysées en MS, MS2 et MS3 par MALDI QIT-TOF (Axima Resonance, Shimadzu) et en MS et MS2 par MALDI-7090™ TOF-TOF (Shimadzu) dans un domaine de masse compris entre 50 et 500 Da. Les ions fragments ont été obtenus selon des processus de fragmentation de basse énergie pour le QIT-TOF et de haute énergie pour le TOF-TOF. Dans un deuxième temps, deux cheveux non segmentés ont été incubés 12 h dans une solution contenant les 3 standards, puis fixés sur une lame de verre conductrice sur laquelle a ensuite été déposée la matrice acide α-cyano-4-hydroxycinnamique (CHCA). Les cheveux ont été analysés selon les mêmes procédures que les standards. Ces analyses ont été complétées par imagerie MALDI avec le QIT-TOF. Les spectres, obtenus avec un pas d’acquisition de 80 μm, ont été retraités par le logiciel BioMap® pour fournir une cartographie des ions d’intérêt. Les spectres de masse des solutions standard obtenus à partir du MALDI QIT-TOF et du MALDI-TOF-TOF montrent un ion précurseur commun (m/z 356,2) sans qu’il soit possible de distinguer les 3 isomères. En MS2, les deux techniques ont permis d’obtenir les ions fils caractéristiques du JWH-122 (m/z 169,1 et 214,1), mais pas ceux des deux autres isomères d’intérêt, la fragmentation du JWH-007 et du JWH-019 menant à deux spectres identiques (pics majoritaires : m/z 155,1 et 228,1). Seule la fragmentation en MS3 par QIT-TOF du JWH-007 et du JWH-019 permet d’identifier un ion fragment unique à m/z 158,1 pour le JWH-007, et quatre ions m/z à 144,1 (pic principal), 116,1, 130,1, et 158,1 pour le JWH-019. L’analyse des cheveux selon les mêmes procédures a donné des résultats comparables. L’imagerie obtenue par le QIT-TOF sur les deux cheveux permet de suivre l’intensité du signal des ions fils le long du cheveu et de distinguer les 3 cannabinoïdes de synthèse (Annexe A). Avec une préparation simple et rapide, une résolution spatiale élevée et une fragmentation MS3, le couplage imagerie MALDI-MS ouvre de nouvelles perspectives pour caractériser dans les milieux biologiques des molécules de structure chimique très voisine. L’application à des cas réels constitue l’étape suivante de ce travail.

Because of inhomogeneous matrix-assisted laser desorption/ionization (MALDI) matrix crystallization and laser shot-to-shot variability, quantitation is not generally performed by MALDI mass spectrometry. Here we introduce a high-throughput MALDI method using an innovative high-density microarray for mass spectrometry (MAMS) technology, which allows semiquantitative measurement of cocaine and its metabolites, benzoylecgonine, cocaethylene, and ecgonine methyl ester. A MAMS slide containing lanes of hydrophilic spots and an automated slider to drag a sample droplet over several small spots can accomplish automatic sample aliquoting and lead to homogeneous crystallization of the matrix-analyte mixture and, thus, to a reproducible signal (average RSD 6%). Four hair samples of self-reported drug users were analyzed in parallel by MALDI-MS/MS and by a validated LC-MS/MS method. The consumption profiles as well as the metabolite-parent drug ratios obtained correlated well, confirming the effectiveness of the MALDI-MS/MS method to establish a calendar of consumption in only 1 mg of hair. The analysis time for 10 hair samples is below 40 min, with 12 replicates per sample. Since only 3 μL of a 20 μL extract is analyzed, complementary assays are possible, such as the detection of additional drugs. The semiquantitative MALDI method worked well with only a small amount of hair and gave results in less than 4 min per sample, including replicates. This was made possible by the use of MAMS slides for sample preparation, which thus present significant advantages over traditional methods in cases where results are required urgently or if samples are scarce.

New designer drugs, as synthetic cannabinoids (SCs), continuously appear on the market and are booming due to their cannabis-like effect. New generation of smokable SCs, structurally dissimilar from D9-tetrahydrocannabinol (THC), have isomers with distinguishable pharmacokinetic parameters and therefore different in vivo effects. The isoforms are misidentified using conventional techniques such as gas or liquid chromatography coupled to mass spectrometry - or tandem mass - spectrometry. The aim of this study was to differentiate three positional isomers (JWH-007, JWH-019 and JWH-122) in single human hair samples, which store numerous substances revealing a way of life and consumption style. Matrix-assisted laser desorption/ionization (MALDI) combined with imaging is an innovative and powerful tool used since few years, especially in forensic research. Herein, we propose an innovative method to monitor the drugs of abuse consumption through direct mapping of the compounds with a high spatial distribution in human hair samples, by state-of-art imaging MALDI-MSn. Three positional SC isomers (JWH-007, JWH-019 and JWH-122) were analysed using high and low fragmentation energy and the resulting MS/MS and even MS3 spectra differentiated the SCs. The MALDI-MS/MS and MS3 imaging was performed on hair soaked in a mixture of the three SCs as well as on hair from self-reported SC user, proving the potential of the technique for a forensic use. Keeping in mind that spatial distribution of organics from whole hair remains a challenge, the described methodology is a very promising analytical tool to probe the consumption of complex drugs and obtain correlation with its origin. (C) 2018 Elsevier B.V. All rights reserved.

Background Amyloidosis suffers from a lack of accurate diagnosis tools. It results from a wrong folding of specific proteins and their identification is essential for proper medical care. Today most patients cases are identified thanks to immunohistochemistry analysis after surgery or biopsy on the defective tissues. The aim of our study is to show that diagnosis and typing of TTR amyloidosis can be immediately and rapidly achieved on formaline fixed and paraffin embedded biopsy samples using MALDI spectrometry, and also on salivary samples.

Many assays are available for the detection of protein carbonyls (PCs). Currently, the measurement of PC groups after their derivatization with 2,4-dinitrophenol hydrazine (DNPH) is widely used for measuring protein oxidation in biological samples. However, this method includes several washing steps. In this context, we have developed a rapid, sensitive, and accurate fluorimetric method adapted to 96-well microplates for the convenient assessment of protein carbonyl level in biological samples. The method reported here is based on the reaction of carbonyl content in proteins with 7-hydrazino-4-nitrobenzo-2,1,3-oxadiazole (NBDH) to form highly fluorescent derivatives via hydrazone formation. PCs were determined using the DNPH and NBDH assays in fully reduced bovine serum albumin (BSA) and plasma and liver homogenates obtained from healthy control rats up the addition of various amounts of HOCl-oxidized BSA (OxBSA). Using the NBDH assay, PC concentrations as low as 0.2nmol/mg were detected with precision as low as 5%. Matrix-assisted laser desorption/ionization time-of-flight (MALDI–TOF) mass spectroscopy was used to successfully identify the formation of the NBDH adducts after derivatization with standard oxidized peptides. Finally, the two methods were further used for PC determination in plasma and liver samples from diabetic and normal rats, showing that the NBDH assay can be reliably used in biological experiments.

Glioblastoma multiforme is one of the most common intracranial tumors encountered in adults. This tumor of very poor prognosis is associated with a median survival rate of approximately 14 months. One of the major issues to better understand the biology of these tumors and to optimize the therapy is to obtain the molecular structure of glioblastoma. MALDI molecular imaging enables location of molecules in tissues without labeling. However, molecular identification in situ is not an easy task. In this paper, we used MALDI imaging coupled to in‐source decay to characterize markers of this pathology. We provided MALDI molecular images up to 30 μm spatial resolution of mouse brain tissue sections. MALDI images showed the heterogeneity of the glioblastoma. In the various zones and at various development stages of the tumor, using our top‐down strategy, we identified several proteins. These proteins play key roles in tumorigenesis. Particular attention was given to the necrotic area with characterization of hemorrhage, one of the most important poor prognosis factors in glioblastoma.

Monitoring bioactive oxidized phospholipids (OxPLs), such as 1-palmitoyl-2-(5'-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC) and 1-palmitoyl-2-(9'-oxononanoyl)-sn-glycero-3-phosphocholine (PONPC), is of major interest as they play a crucial role in a variety of age related diseases, e.g., in the development and progression of atherosclerosis. Since they are in low abundance in samples like oxidized low-density lipoproteins (OxLDL) and human plasma, respectively, their analysis as risk biomarkers requires the combination of an efficient selective sample preparation with highly sensitive detection methods, such as liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). In this study, a nanoparticle-based strategy for successful trapping and enrichment of aldehyde-containing oxidized phospholipids is presented. The concept involves a derivatization step with a bifunctional reagent containing both a hydrazide group for hydrazone formation with carbonyl-containing PLs and a thiol moiety for subsequent trapping on GNPs. After washing, the trapped analytes are quantitatively released from the nanoparticles' surface by transimination with hydroxylamine. The released oxime-derivatives of the carbonylated-OxPLs are subsequently analyzed by LC-ESI-MS/MS in the selected reaction monitoring scan mode. Several parameters of this workflow were optimized. With the optimized nanoparticle-based extraction and enrichment step, very clean extracts of these biomarkers can be obtained and the detection limits can be significantly decreased from 2.76 and 2.65 nM for PONPC and POVPC, respectively, to 0.17 and 0.44 nM. The applicability of this nanoparticle-based sample preparation concept was demonstrated by successful extraction of oxidized phospholipids from biological samples, such as human plasma, MDA-modified LDL and Cu2+-oxidized LDL.

Bevacizumab induces normalization of abnormal blood vessels, making them less leaky. By binding to vascular endothelial growth factor, it indirectly attacks the vascular tumor mass. The optimal delivery of targeted therapies including monoclonal antibodies or anti-angiogenesis drugs to the target tissue highly depends on the blood-brain barrier permeability. It is therefore critical to investigate how drugs effectively reach the tumor. In situ investigation of drug distribution could provide a better understanding of pharmacological agent action and optimize chemotherapies for solid tumors. We developed an imaging method coupled to protein identification using matrix-assisted laser desorption/ionization mass spectrometry. This approach monitored bevacizumab distribution within the brain structures, and especially within the tumor, without any labeling.

Background Mutations of MAGEL2 have been reported in patients presenting with autism, and loss of MAGEL2 is also associated with Prader-Willi syndrome, a neurodevelopmental genetic disorder. This study aimed to determine the behavioral phenotype of Magel2-deficient adult mice, to characterize the central oxytocin (OT) system of these mutant mice, and to test the curative effect of a peripheral OT treatment just after birth. Methods We assessed the social and cognitive behavior of Magel2-deficient mice, analyzed the OT system of mutant mice treated or not by a postnatal administration of OT, and determined the effect of this treatment on the brain. Results Magel2 inactivation induces a deficit in social recognition and social interaction and a reduced learning ability in adult male mice. In these mice, we reveal anatomical and functional modifications of the OT system and show that these defects change from birth to adulthood. Daily administration of OT in the first postnatal week was sufficient to prevent deficits in social behavior and learning abilities in adult mutant male mice. We show that this OT treatment partly restores a normal OT system. Thus, we report that an alteration of the OT system around birth has long-term consequences on behavior and on cognition. Importantly, an acute OT treatment of Magel2-deficient pups has a curative effect. Conclusions Our study reveals that OT plays a crucial role in setting social behaviors during a period just after birth. An early OT treatment in this critical period could be a novel therapeutic approach for the treatment of neurodevelopmental disorders such as Prader-Willi syndrome and autism.

The melanoma cell adhesion molecule (CD146) contains a circulating proteolytic variant (sCD146), which is involved in inflammation and angiogenesis. Its circulating level is modulated in different pathologies, but its intracellular transduction pathways are still largely unknown. Using peptide pulldown and mass spectrometry, we identified angiomotin as a sCD146-associated protein in endothelial progenitor cells (EPC). Interaction between angiomotin and sCD146 was confirmed by enzyme-linked immunosorbent assay (ELISA), homogeneous time-resolved fluorescence, and binding of sCD146 on both immobilized recombinant angiomotin and angiomotin-transfected cells. Silencing angiomotin in EPC inhibited sCD146 angiogenic effects, i.e. EPC migration, proliferation, and capacity to form capillary-like structures in Matrigel. In addition, sCD146 effects were inhibited by the angiomotin inhibitor angiostatin and competition with recombinant angiomotin. Finally, binding of sCD146 on angiomotin triggered the activation of several transduction pathways that were identified by antibody array. These results delineate a novel signaling pathway where sCD146 binds to angiomotin to stimulate a proangiogenic response. This result is important to find novel target cells of sCD146 and for the development of therapeutic strategies based on EPC in the treatment of ischemic diseases.

Altered development of the human cerebral cortex can cause severe malformations with often intractable focal epileptic seizures and may participate in common pathologies, notably epilepsy. This raises important conceptual and therapeutic issues. Two missense mutations in the sushi repeat-containing protein SRPX2 had been previously identified in epileptic disorders with or without structural developmental alteration of the speech cortex. In the present study, we aimed to decipher the precise developmental role of SRPX2, to have a better knowledge on the consequences of its mutations, and to start addressing therapeutic issues through the design of an appropriate animal model. Using an in utero Srpx2 silencing approach, we show that SRPX2 influences neuronal migration in the developing rat cerebral cortex. Wild-type, but not the mutant human SRPX2 proteins, rescued the neuronal migration phenotype caused by Srpx2 silencing in utero, and increased alpha-tubulin acetylation. Following in utero Srpx2 silencing, spontaneous epileptiform activity was recorded post-natally. The neuronal migration defects and the post-natal epileptic consequences were prevented early in embryos by maternal administration of tubulin deacetylase inhibitor tubacin. Hence epileptiform manifestations of developmental origin could be prevented in utero, using a transient and drug-based therapeutic protocol.