Microbiota from Alzheimer's patients induce deficits in cognition and hippocampal neurogenesis.

Alzheimer's disease is a complex neurodegenerative disorder leading to a decline in cognitive function and mental health. Recent research has positioned the gut microbiota as an important susceptibility factor in Alzheimer's disease by showing specific alterations in the gut microbiome composition of Alzheimer's patients and in rodent models. However, it is unknown whether gut microbiota alterations are causal in the manifestation of Alzheimer's symptoms. To understand the involvement of Alzheimer's patient gut microbiota in host physiology and behaviour, we transplanted faecal microbiota from Alzheimer's patients and age-matched healthy controls into microbiota-depleted young adult rats. We found impairments in behaviours reliant on adult hippocampal neurogenesis, an essential process for certain memory functions and mood, resulting from Alzheimer's patient transplants. Notably, the severity of impairments correlated with clinical cognitive scores in donor patients. Discrete changes in the rat caecal and hippocampal metabolome were also evident. As hippocampal neurogenesis cannot be measured in living humans but is modulated by the circulatory systemic environment, we assessed the impact of the Alzheimer's systemic environment on proxy neurogenesis readouts. Serum from Alzheimer's patients decreased neurogenesis in human cells in vitro and were associated with cognitive scores and key microbial genera. Our findings reveal for the first time, that Alzheimer's symptoms can be transferred to a healthy young organism via the gut microbiota, confirming a causal role of gut microbiota in Alzheimer's disease, and highlight hippocampal neurogenesis as a converging central cellular process regulating systemic circulatory and gut-mediated factors in Alzheimer's.

Glycerophospholipid and detoxification pathways associated with small for gestation age pathophysiology: discovery metabolomics analysis in the SCOPE cohort.

INTRODUCTION: Small for gestational age (SGA) may be associated with neonatal morbidity and mortality. Our understanding of the molecular pathways implicated is poor. OBJECTIVES: Our aim was to determine the metabolic pathways involved in the pathophysiology of SGA and examine their variation between maternal biofluid samples. METHODS: Plasma (Cork) and urine (Cork, Auckland) samples were collected at 20 weeks' gestation from nulliparous low-risk pregnant women participating in the SCOPE study. Women who delivered an SGA infant (birthweight < 10th percentile) were matched to controls (uncomplicated pregnancies). Metabolomics (urine) and lipidomics (plasma) analyses were performed using ultra performance liquid chromatography-mass spectrometry. Features were ranked based on FDR adjusted p-values from empirical Bayes analysis, and significant features putatively identified. RESULTS: Lipidomics plasma analysis revealed that 22 out of the 33 significantly altered lipids annotated were glycerophospholipids; all were detected in higher levels in SGA. Metabolomic analysis identified reduced expression of metabolites associated with detoxification (D-Glucuronic acid, Estriol-16-glucuronide), nutrient absorption and transport (Sulfolithocholic acid) pathways. CONCLUSIONS: This study suggests higher levels of glycerophospholipids, and lower levels of specific urine metabolites are implicated in the pathophysiology of SGA. Further research is needed to confirm these findings in independent samples.

Association between phospholipid metabolism in plasma and spontaneous preterm birth: a discovery lipidomic analysis in the cork pregnancy cohort.

INTRODUCTION: Preterm birth (PTB) is defined as birth occurring before 37 weeks' gestation, affects 5-9% of all pregnancies in developed countries, and is the leading cause of perinatal mortality. Spontaneous preterm birth (sPTB) accounts for 31-50% of all PTB, but the underlying pathophysiology is poorly understood. OBJECTIVE: This study aimed to decipher the lipidomics pathways involved in pathophysiology of sPTB. METHODS: Blood samples were taken from SCreening fOr Pregnancy Endpoints (SCOPE), an international study that recruited 5628 nulliparous women, with a singleton low-risk pregnancy. Our analysis focused on plasma from SCOPE in Cork. Discovery profiling of the samples was undertaken using liquid chromatography-mass spectrometry Lipidomics, and features significantly altered between sPTB (n = 16) and Control (n = 32) groups were identified using empirical Bayes testing, adjusting for multiple comparisons. RESULTS: Twenty-six lipids showed lower levels in plasma of sPTB compared to controls (adjusted p < 0.05), including 20 glycerophospholipids (12 phosphatidylcholines, 7 phosphatidylethanolamines, 1 phosphatidylinositol) and 6 sphingolipids (2 ceramides and 4 sphingomyelines). In addition, a diaglyceride, DG (34:4), was detected in higher levels in sPTB compared to controls. CONCLUSIONS: We report reduced levels of plasma phospholipids in sPTB. Phospholipid integrity is linked to biological membrane stability and inflammation, while storage and breakdown of lipids have previously been implicated in pregnancy complications. The contribution of phospholipids to sPTB as a cause or effect is still unclear; however, our results of differential plasma phospholipid expression represent another step in advancing our understanding of the aetiology of sPTB. Further work is needed to validate these findings in independent pregnancy cohorts.

Blood biomarker discovery in drug-free schizophrenia: the contributionof proteomics and multiplex immunoassays.

INTRODUCTION: Recent evidence supports an association between systemic abnormalities and the pathology of psychotic disorders which has led to the search for peripheral blood-based biomarkers. Areas covered: Here, we summarize blood biomarker findings in schizophrenia from the literature identified by two methods currently driving biomarker discovery in the human proteome; mass spectrometry and multiplex immunoassay. From a total of 14 studies in the serum or plasma of drug-free schizophrenia patients; 47 proteins were found to be significantly altered twice or more, in the same direction. Pathway analysis was performed on these proteins, and the resulting pathways discussed in relation to schizophrenia pathology. Future directions are also discussed, with particular emphasis on the potential for high-throughput validation techniques such as data-independent analysis for confirmation of biomarker candidates. Expert commentary: We present promising findings that point to a convergence of pathophysiological mechanisms in schizophrenia that involve the acute-phase response, glucocorticoid receptor signalling, coagulation, and lipid and glucose metabolism.

The 'middle-aging' brain.

Middle age has historically been an understudied period of life compared to older age, when cognitive and brain health decline are most pronounced, but the scope for intervention may be limited. However, recent research suggests that middle age could mark a shift in brain aging. We review emerging evidence on multiple levels of analysis indicating that midlife is a period defined by unique central and peripheral processes that shape future cognitive trajectories and brain health. Informed by recent developments in aging research and lifespan studies in humans and animal models, we highlight the utility of modeling non-linear changes in study samples with wide subject age ranges to distinguish life stage-specific processes from those acting linearly throughout the lifespan.

Exercise mitigates a gut microbiota-mediated reduction in adult hippocampal neurogenesis and associated behaviours in rats.

Lifestyle factors, especially exercise, impact the manifestation and progression of psychiatric and neurodegenerative disorders such as depression and Alzheimer's disease, mediated by changes in hippocampal neuroplasticity. The beneficial effects of exercise may be due to its promotion of adult hippocampal neurogenesis (AHN). Gut microbiota has also been showed to be altered in a variety of brain disorders, and disturbances of the microbiota have resulted in alterations in brain and behaviour. However, whether exercise can counteract the negative effects of altered gut microbiota on brain function remains under explored. To this end, chronic disruption of the gut microbiota was achieved using an antibiotic cocktail in rats that were sedentary or allowed voluntary access to running wheels. Sedentary rats with disrupted microbiota displayed impaired performance in hippocampal neurogenesis-dependent tasks: the modified spontaneous location recognition task and the novelty suppressed feeding test. Performance in the elevated plus maze was also impaired due to antibiotics treatment. These behaviours, and an antibiotics-induced reduction in AHN were attenuated by voluntary exercise. The effects were independent of changes in the hippocampal metabolome but were paralleled by caecal metabolomic changes. Taken together these data highlight the importance of the gut microbiota in AHN-dependent behaviours and demonstrate the power of lifestyle factors such as voluntary exercise to attenuate these changes.

Evaluation of hydrophilic interaction chromatography versus reversed-phase chromatography for fast aqueous species distribution analysis of Nickel(II)-Histidine complex species.

Nickel (Ni) is a trace heavy metal of importance in biological and environmental systems, with well documented allergy and carcinogenic effects in humans. With Ni(II) as the dominant oxidation state, the elucidation of the coordination mechanisms and labile complex species responsible for its transportation, toxicity, allergy, and bioavailability is key to understanding its biological effects and location in living systems. Histidine (His) is an essential amino acid that contributes to protein structure and activity and in the coordination of Cu(II) and Ni(II) ions. The aqueous low molecular weight Ni(II)-Histidine complex consists primarily of two stepwise complex species Ni(II)(His)1 and Ni(II)(His)2 in the pH range of 4 to 12. Four chromatographic columns, including the superficially porous Poro-shell EC-C18, Halo RP-amide and Poro-shell bare silica-HILIC columns, alongside a Zic-cHILIC fully porous column, were evaluated for the fast separation of the individual Ni(II)-Histidine species. Of these the Zic-cHILIC exhibited high efficiency and selectivity to distinguish between the two stepwise species Ni(II)His1 and Ni(II)His2 as well as free Histidine, with a fast separation within 120 s at a flow rate of 1 ml/min. This HILIC method utilizing the Zic-cHILIC column was initially optimized for the simultaneous analysis of Ni(II)-His-species using UV detection with a mobile phase consisting of 70% ACN and sodium acetate buffer at wwpH 6. Furthermore, the aqueous metal complex species distribution analysis for the low molecular weight Ni(II)-histidine system was chromatographically determined at various metal-ligand ratios and as a function of pH. The identities of Ni(II)His1 and Ni(II)-His2 species were confirmed using HILIC electrospray ionization- mass spectrometry (HILIC-ESI-MS) at negative mode.

Image analysis tools and emerging algorithms for expression proteomics.

Since their origins in academic endeavours in the 1970s, computational analysis tools have matured into a number of established commercial packages that underpin research in expression proteomics. In this paper we describe the image analysis pipeline for the established 2-DE technique of protein separation, and by first covering signal analysis for MS, we also explain the current image analysis workflow for the emerging high-throughput 'shotgun' proteomics platform of LC coupled to MS (LC/MS). The bioinformatics challenges for both methods are illustrated and compared, whereas existing commercial and academic packages and their workflows are described from both a user's and a technical perspective. Attention is given to the importance of sound statistical treatment of the resultant quantifications in the search for differential expression. Despite wide availability of proteomics software, a number of challenges have yet to be overcome regarding algorithm accuracy, objectivity and automation, generally due to deterministic spot-centric approaches that discard information early in the pipeline, propagating errors. We review recent advances in signal and image analysis algorithms in 2-DE, MS, LC/MS and Imaging MS. Particular attention is given to wavelet techniques, automated image-based alignment and differential analysis in 2-DE, Bayesian peak mixture models, and functional mixed modelling in MS, and group-wise consensus alignment methods for LC/MS.

Anxiety, depression, and stress in response to the coronavirus disease-19 pandemic.

OBJECTIVE: The objective of the study was to determine the state of anxiety, depression, and stress present in the society during the development of the 2019 coronavirus pandemic. METHODS: Mixed methods study; a three-section questionnaire was developed which included sociodemographic, perceptions, emotions, and behaviors related to the 2019 coronavirus pandemic, and two emotional assessment psychometric tests. The proportions and confidence intervals of the variables were calculated and compared using the Chi-square test. RESULTS: More than 40% of the subjects presented some degree of anxiety and 41.3% depression; the proportion of stress was < 30%. Of the subjects who experienced anxiety, 18.6% also had moderate-to-very severe depression or stress. CONCLUSION: There are emotional indicators derived from the 2019 coronavirus pandemic in almost half of the study population. The identification and timely treatment of these states could lessen the psychological impact due to 2019 coronavirus.

OBJETIVO: Determinar el estado de ansiedad, depresión y estrés en la sociedad durante el desarrollo de la pandemia de COVID-19. MÉTODO: Estudio de métodos mixtos. Se desarrolló un cuestionario de tres secciones que incluía aspectos sociodemográficos, percepciones, emociones y comportamientos relacionados con la pandemia de COVID-19, y dos pruebas psicométricas de evaluación emocional. Las proporciones y los intervalos de confianza de las variables se calcularon y compararon mediante la prueba de ji al cuadrado. RESULTADOS: Más del 40% de los sujetos presentaron algún grado de ansiedad y el 41,3% de depresión; la proporción de estrés fue inferior al 30%. De los sujetos que experimentaron ansiedad, el 18.6% también tenía depresión o estrés moderado a muy intenso. CONCLUSIÓN: Existen indicadores emocionales derivados de la pandemia de COVID-19 en casi la mitad de la población del estudio. La identificación y el tratamiento oportuno de estos estados podrían disminuir el impacto psicológico debido al COVID-19.

Effect of L-Ergothioneine on the metabolic plasma profile of the RUPP rat model of pre-eclampsia.

INTRODUCTION: Pre-eclampsia is a major cause of maternal and fetal mortality and morbidity worldwide. Its pathophysiology remains unclear, but mitochondrial dysfunction and oxidative stress have been implicated. L-Ergothioneine is a naturally occurring, water-soluble betaine, that has demonstrated antioxidant properties. Using the reduced uterine perfusion pressure (RUPP) rat model of pre-eclampsia, this study aimed to define the plasma metabolic profile following treatment with L-Ergothioneine. METHODS: The effect of L-Ergothioneine (ET) treatment was explored using in vivo treatment in rats: Sham control (SC, n = 5), RUPP control (RC, n = 5), Sham +ET (ST, n = 5), RUPP +ET (RT, n = 5). Differential expression of plasma metabolites were obtained using untargeted liquid chromatography coupled to mass spectrometry. Statistical analysis was performed on normalised data comparing RC to SC, RT to RC, and RT to ST. Metabolites significantly altered (FDR < 0.05) were identified through database search. RESULTS: We report significantly lower levels of L-palmitoylcarnitine in RC compared to SC, a fatty acyl substrate involved in beta-oxidation in the mitochondria. We report that a metabolite that has been associated with oxidative stress (Glutamylcysteine) was detected at significantly higher levels in RT vs RC and RT vs ST. Five metabolites associated with inflammation were significantly lower in RT vs RC and three metabolites in RT vs ST, demonstrating the anti-inflammatory effects of ET in the RUPP rat model of pre-eclampsia. CONCLUSIONS: L-Ergothioneine may help preserve mitochondrial function by increasing antioxidant levels, and reducing inflammatory responses associated with pre-eclampsia. This study shows the potential of L-Ergothioneine as a treatment for pre-eclampsia.

5th BSPR-EBI meeting, proteomics: from Technology to New Biology 8-10 July 2008, Wellcome Trust Conference Centre, Hinxton, Cambridge, UK.

This paper reports on the 5(th) joint British Society for Proteome Research (BSPR) and European Bioinformatics Institute (EBI) meeting which took place at the Wellcome Trust Conference Centre, Cambridge, UK, from the 8(th) to 10(th) July, 2008. As in previous years, the meeting attracted leading experts in the field who presented the latest cutting edge in proteomics. The meeting was entitled "Proteomics: From Technology to New Biology" taking into account the major transition proteomics has undergone in the past few years. In particular, the use of multiple reaction monitoring (MRM)-based targeted experiments for absolute quantification and validation of proteins was the hot topic of the meeting. Attended by some 250 delegates, the conference was extremely well organised and provided a great opportunity for discussion and initiation of new collaborations.

2-D DIGE analysis implicates cytoskeletal abnormalities in psychiatric disease.

The mechanisms underlying white matter changes in psychiatric disease are not known. We aimed to characterise the differential protein expression in deep white matter from the dorsolateral prefrontal cortex from 35 schizophrenia, 35 bipolar disorder, and 35 control subjects, from the Stanley Array Collection. We used 2-D DIGE to profile for protein expression changes in the brain. We found 70 protein spots to be significantly differentially expressed between disease and control subjects (ANCOVA, p<0.05), 46 of which were subsequently identified by LC-MS/MS. The proteins identified included novel disease candidates as well as proteins that have previously been reported as abnormal in schizophrenia, thus reinforcing their association with the disease. Furthermore, we confirmed the direction of change for three proteins using ELISA, namely neurofilament-light, amphiphysin II, and Rab-GDP-alpha, in a subset of the Stanley Array Collection. In addition, altered expression of neurofilament-light, amphiphysin II, and Rab-GDP-alpha was not observed in the cortex of mice chronically treated with haloperidol, making it less likely that these alterations are a consequence of neuroleptic medication. The data presented here strongly suggest disruption of the cytoskeleton and its associated signal transduction proteins in schizophrenia, and to a lesser extent in bipolar disorder.

Assessing the use of thermal treatment to preserve the intact proteomes of post-mortem heart and brain tissue.

Protein degradation that occurs in tissue during post-mortem interval or sample preparation is problematic in quantitative analyses as confounding variables may arise. Ideally, such artefacts should be prevented by preserving the native proteome during sample preparation. We assessed the efficacy of thermal treatment (TT) to preserve the intact proteome of mouse heart and brain tissue in comparison to standard snap-freezing with liquid nitrogen (LN). Tissue samples were collected, either snap frozen (LN), subjected to TT, or snap frozen followed by thermal treatment, and subsequently analysed by 2-DE. In heart tissue, following quantitative image analysis, we observed 77 proteins that were significantly altered across the three treatment groups (ANOVA, p<0.05). Principal component and clustering analyses revealed LN and TT to be equally beneficial. These findings were confirmed by MS identification of the significantly altered proteins. In brain tissue, 189 proteins were significantly differentially expressed across the three treatment groups (ANOVA, p<0.05). Brain tissue appeared to be more responsive to TT than heart and distinct clusters of differentially expressed proteins were observed across treatments. Overall, TT of brain tissue appears to have beneficial effects on protein stabilisation during sample preparation with preservation of high-molecular-weight proteins and reduction in protein fragmentation.

Comparative analysis of OFFGel, strong cation exchange with pH gradient, and RP at high pH for first-dimensional separation of peptides from a membrane-enriched protein fraction.

The analysis and quantitation of membrane proteins have proved challenging for proteomics. Although several approaches have been introduced to complement gel-based analysis of intact proteins, the literature is rather limited in comparing major emerging approaches. Peptide fractionation using IEF (OFFGel), strong cation exchange HPLC using a pH gradient (SCX-pG), and RP HPLC at high pH, have been shown to increase peptide and protein identification over classic MudPIT approaches. This article compares these three approaches for first-dimensional separation of peptides using a detergent phase (Triton X-114) enriched membrane fraction from mouse cortical brain tissue. Results indicate that RP at high pH (pH 10) was superior for the identification of more peptides and proteins in comparison to the OFFGel or the SCX-pG approaches. In addition, gene ontology analysis (GOMiner) revealed that RP at high pH (pH 10) successfully identified an increased number of proteins with "membrane" ontology, further confirming its suitability for membrane protein analysis, in comparison to SCX-pG and OFFGel techniques.

ApoE elevation is associated with the persistence of psychotic experiences from age 12 to age 18: Evidence from the ALSPAC birth cohort.

Apolipoproteins, which play important roles in lipid metabolism, innate immunity and synaptic signalling, have been implicated in first episode psychosis and schizophrenia. This is the first study to investigate plasma apolipoprotein expression in children with psychotic experiences that persist into adulthood. Here, using semi-targeted proteomic analysis we compared plasma apolipoprotein expression levels in age 12 subjects who reported psychotic experiences at both age 12 and age 18 (n = 37) with age-matched subjects who only experienced psychotic experiences (PEs) at age 12 (n = 38). Participants were recruited from the UK Avon Longitudinal Study of Parents and Children (ALSPAC) cohort who participated in psychiatric assessment interviews at ages 12 and 18. We identified apoE, a protein with significant regulatory activity on cholesterol metabolism in the brain, to be significantly up regulated (p < 0.003) in those with persistent psychotic experiences. We confirmed this finding in these samples using ELISA. Our findings indicate elevated plasma apoE in age 12 children who experience PEs is associated with persistence psychotic experiences.

Integrated Lipidomics and Proteomics Point to Early Blood-Based Changes in Childhood Preceding Later Development of Psychotic Experiences: Evidence From the Avon Longitudinal Study of Parents and Children.

BACKGROUND: The identification of early biomarkers of psychotic experiences (PEs) is of interest because early diagnosis and treatment of those at risk of future disorder is associated with improved outcomes. The current study investigated early lipidomic and coagulation pathway protein signatures of later PEs in subjects from the Avon Longitudinal Study of Parents and Children cohort. METHODS: Plasma of 115 children (12 years of age) who were first identified as experiencing PEs at 18 years of age (48 cases and 67 controls) were assessed through integrated and targeted lipidomics and semitargeted proteomics approaches. We assessed the lipids, lysophosphatidylcholines (n = 11) and phosphatidylcholines (n = 61), and the protein members of the coagulation pathway (n = 22) and integrated these data with complement pathway protein data already available on these subjects. RESULTS: Twelve phosphatidylcholines, four lysophosphatidylcholines, and the coagulation protein plasminogen were altered between the control and PEs groups after correction for multiple comparisons. Lipidomic and proteomic datasets were integrated into a multivariate network displaying a strong relationship between most lipids that were significantly associated with PEs and plasminogen. Finally, an unsupervised clustering approach identified four different clusters, with one of the clusters presenting the highest case-control ratio (p < .01) and associated with a higher concentration of smaller low-density lipoprotein cholesterol particles. CONCLUSIONS: Our findings indicate that the lipidome and proteome of subjects who report PEs at 18 years of age are already altered at 12 years of age, indicating that metabolic dysregulation may contribute to an early vulnerability to PEs and suggesting crosstalk between these lysophosphatidylcholines, phosphatidylcholines, and coagulation and complement proteins.

1st Irish proteomics workshop April 17th 2008, University College Dublin, Conway Institute, Dublin, Ireland.

The workshop assembled an excellent collection of speakers from across Ireland and beyond who presented many interesting and diverse topical issues. Various proteomic applications were discussed throughout the day ranging from 2-DE and 2-D DIGE, to GeLC-MS/MS, high density Protein and Antibody Arrays, with a particular focus on the importance of quantitative mass spectrometry in proteomics.

Blood-Based Protein Changes in Childhood Are Associated With Increased Risk for Later Psychotic Disorder: Evidence From a Nested Case-Control Study of the ALSPAC Longitudinal Birth Cohort.

The identification of early biological changes associated with the psychotic disorder (PD) is important as it may provide clues to the underlying pathophysiological mechanisms. We undertook the first proteomic profiling of blood plasma samples of children who later develop a PD. Participants were recruited from the UK Avon Longitudinal Study of Parents and Children (ALSPAC) cohort who also participated in psychiatric assessment interviews at age 18. Protein expression levels at age 11 were compared between individuals who developed PD at age 18 (n = 37) with population-based age-matched controls (n = 38). Sixty out of 181 plasma proteins profiled were found to be differentially expressed (P < .05) in children with an outcome of the PD. Thirty-four of these proteins were found to be differentially expressed following correction for multiple comparisons. Pathway analysis implicated the complement and coagulation cascade. A second, targeted proteomic approach was used to verify these findings in age 11 plasma from subjects who reported psychotic experiences at age 18 (n = 40) in comparison to age-matched controls (n = 66). Our findings indicate that the complement and coagulation system is dysregulated in the blood during childhood before the development of the PD.

Dataset of mouse hippocampus profiled by LC-MS/MS for label-free quantitation.

This dataset reports on the analysis of mouse hippocampus by LC-MS/MS, from mice fed a diet that was either deficient in n-3 FA (n-3 Def) or sufficient in n-3 FA (n-3 Adq). Label free quantitative (LFQ) analysis of the mass spectrometry data identified 1008 quantifiable proteins, 115 of which were found to be differentially expressed between the two dietary groups (n=8 per group). This data article refers to the research article "Omega-3 fatty acid deficiency disrupts endocytosis, neuritogenesis, and mitochondrial protein pathways in the mouse hippocampus" (English et al., 2013 [1]), in which a more comprehensive interpretation and analysis of the data is given.

Omega-3 fatty acid deficiency disrupts endocytosis, neuritogenesis, and mitochondrial protein pathways in the mouse hippocampus.

Omega-3 fatty acid (n-3 FA) deficiency is an environmental risk factor for schizophrenia, yet characterization of the consequences of deficiency at the protein level in the brain is limited. We aimed to identify the protein pathways disrupted as a consequence of chronic n-3 deficiency in the hippocampus of mice. Fatty acid analysis of the hippocampus following chronic dietary deficiency revealed a 3-fold decrease (p < 0.001) in n-3 FA levels. Label free LC-MS/MS analysis identified and profiled 1008 proteins, of which 114 were observed to be differentially expressed between n-3 deficient and control groups (n = 8 per group). The cellular processes that were most implicated were neuritogenesis, endocytosis, and exocytosis, while specific protein pathways that were most significantly dysregulated were mitochondrial dysfunction and clathrin mediated endocytosis (CME). In order to characterize whether these processes and pathways are ones influenced by antipsychotic medication, we used LC-MS/MS to test the differential expression of these 114 proteins in the hippocampus of mice chronically treated with the antipsychotic agent haloperidol. We observed 23 of the 114 proteins to be differentially expressed, 17 of which were altered in the opposite direction to that observed following n-3 deficiency. Overall, our findings point to disturbed synaptic function, neuritogenesis, and mitochondrial function as a consequence of dietary deficiency in n-3 FA. This study greatly aids our understanding of the molecular mechanism by which n-3 deficiency impairs normal brain function, and provides clues as to how n-3 FA exert their therapeutic effect in early psychosis.