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Background: Disruption in normal development of the human prefrontal cortex (PFC) may lead to cognitive dysfunction that manifests in individuals with schizophrenia. We sought to identify genes associated with age that are implicated in schizophrenia. Methods: We generated genome-wide expression profiles for the PFCs of humans ranging in age from 1 month to 49 years using the Affymetrix HG-U133 plus 2.0 microarrays (54 675 transcripts). Based on the criteria of significance (false discovery rate [FDR]-adjusted q < 0.001 and [r.sup.2] > 0.6), we identified the genes associated with age in the PFC. We then performed functional annotation analyses of age-associated genes using the Gene Ontology and the Genetic Association Database (GAD). Results: We found robust age-dependent changes in gene expression in the PFCs of humans (2281 transcripts). The GAD analysis revealed that schizophrenia was an over-represented disease class, with 42 susceptibility genes included (p< 0.001, fold enrichment = 1.66, FDR = 1.5%). Among the 42 genes, glutamate receptor genes (GRIA1, GRIK1, GRIK2, GRIN2D, GRIP1, GRM5, GRM7and SLC1A6) were consistently downregulated across age. We confirmed microarray gene expression changes by the quantitative polymerase chain reaction experiment. Limitations: Although numerous genes undergo robust changes in expression during the PFC development, some of the changes may be confounded by known and unknown factors that are intrinsic to the postmortem brain studies. Conclusion: Multiple schizophrenia susceptibility genes undergo age-dependent expression changes in the human PFC, and any disruption in those genes during the critical period of development may predispose the individuals to schizophrenia., Introduction The human prefrontal cortex (PFC) continues to develop into adolescence and early adulthood and is one of the last cortical regions to mature structurally and functionally. (1) It is [...]

Although previous studies have reported an association between patient-reported somatic symptom severity and the development of posttraumatic stress disorder (PTSD) or major depressive disorder (MDD) in injured military service members (SMs), conclusions from other studies regarding the association between clinician-determined injury severity and PTSD or MDD remain unclear. The present study investigated whether somatic symptoms or injury severity predict the development of probable PTSD or MDD in wounded SMs medically evacuated from combat areas. Data including SM demographic characteristics, clinician-determined injury severity (i.e., Injury Severity Score [ISS] and Abbreviated Injury Scale [AIS] values), and self-report assessments of PTSD (PTSD Checklist-Civilian Version), MDD (Patient Health Questionnaire [PHQ]-9), and somatic symptoms (PHQ-15) were analyzed. A total of 2,217 SMs completed at least one self-assessment between 2003 and 2014, with 425 having completed assessments at each assessment period (AP), conducted 1-75 (AP1), 76-165 (AP2), and 166-255 (AP3) days postinjury. Between AP1 and AP3, the rates of probable PTSD and MDD increased from 3.0% to 11.7% and from 2.8% to 9.2%, respectively. Somatic symptom severity at AP1 predicted probable PTSD and MDD at all three APs, odds ratios (ORs) = 3.5-11.5; however, ISS values did not predict probable PTSD or MDD at any AP, ORs = 0.6-0.9. This suggests that the initial severity of self-reported somatic symptoms rather than clinician-determined injury severity predicts the development of probable PTSD and MDD in wounded SMs. [ABSTRACT FROM AUTHOR]

Early life stress presents an important risk factor for drug addiction and comorbid depression and anxiety through persistent effects on the mesolimbic dopamine pathways. Using an early life stress model for child neglect (a single 24 h episode of maternal deprivation, MD) in rats, recent published works from our lab show that MD induces dysfunction in the ventral tegmental area and its negative controller, the lateral habenula (LHb). MD‐induced potentiation of glutamatergic synaptic transmission onto LHb neurons shifts the coordination of excitation/inhibition (E/I) balance towards excitation, resulting in an increase in the overall spontaneous neuronal activity with elevation in bursting and tonic firing, and in the intrinsic excitability of LHb neurons in early adolescent male rats. Here, we explored how MD affects intravenous morphine self‐administration (MSA) acquisition and sucrose preference as well as glutamatergic synaptic function in LHb neurons of adult male rats self‐administering morphine. We found that MD‐induced increases in LHb neuronal and glutamatergic synaptic activity and E/I ratio persisted into adulthood. Moreover, MD significantly reduced morphine intake, triggered anhedonia‐like behaviour in the sucrose preference test and was associated with persistent glutamatergic potentiation 24 h after the last MSA session. MSA also altered the decay time kinetics of α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor (AMPAR) currents in LHb neurons of control rats during this time period. Our data highlight that early life stress‐induced glutamatergic plasticity in LHb may dampen the positive reinforcing and motivational properties of both natural rewards and opioids, and may contribute to the development of anhedonia and dysphoric states associated with opioids. [ABSTRACT FROM AUTHOR]

Abstract Background Although much progress has been made on antipsychotic drug development, precise mechanisms behind the action of typical and atypical antipsychotics are poorly understood. Methods We performed genome-wide expression profiling to study effects of typical antipsychotics and atypical antipsychotics in the postmortem liver of schizophrenia patients using microarrays (Affymetrix U133 plus2.0). We classified the subjects into typical antipsychotics (n = 24) or atypical antipsychotics (n = 26) based on their medication history, and compared gene expression profiles with unaffected controls (n = 34). We further analyzed individual antipsychotic effects on gene expression by sub-classifying the subjects into four major antipsychotic groups including haloperidol, phenothiazines, olanzapine and risperidone. Results Typical antipsychotics affected genes associated with nuclear protein, stress responses and phosphorylation, whereas atypical antipsychotics affected genes associated with golgi/endoplasmic reticulum and cytoplasm transport. Comparison between typical antipsychotics and atypical antipsychotics further identified genes associated with lipid metabolism and mitochondrial function. Analyses on individual antipsychotics revealed a set of genes (151 transcripts, FDR adjusted p < 0.05) that are differentially regulated by four antipsychotics, particularly by phenothiazines, in the liver of schizophrenia patients. Conclusion Typical antipsychotics and atypical antipsychotics affect different genes and biological function in the liver. Typical antipsychotic phenothiazines exert robust effects on gene expression in the liver that may lead to liver toxicity. The genes found in the current study may benefit antipsychotic drug development with better therapeutic and side effect profiles.

Background: Previous studies suggested that opiate withdrawal may increase anxiety and disrupt brain-derived neurotrophic factor function, but the effects of i.v. morphine self-administration on these measures remain unclear. Methods: Adult male Sprague-Dawley rats were implanted with a catheter in the jugular vein. After 1 week of recovery, the animals were allowed to self-administer either i.v. morphine (0.5 mg/kg per infusion, 4 h/d) or saline in the operant conditioning chambers. The acoustic startle reflex and prepulse inhibition were measured at a baseline and on self-administration days 1, 3, 5, and 7 (1- and 3-hour withdrawal). Blood samples were collected on self-administration days 3, 5, and 7 from separate cohorts of animals, and the levels of brain-derived neurotrophic factor and corticosterone were assayed using the enzymelinked immunosorbent assay method. Results: Compared with the saline group, the morphine self-administration group showed hyper-locomotor activity and reduced defecation during the self-administration. The morphine self-administration increased acoustic startle reflex at 1-hour but not 3-hour withdrawal from morphine and disrupted prepulse inhibition at 3-hour but not 1-hour withdrawal. The blood brain-derived neurotrophic factor levels were decreased in the morphine self-administration group at selfadministration days 3 and 5, while the corticosterone levels remained unchanged throughout the study. Conclusions: The current findings suggest that spontaneous withdrawal from i.v. morphine self-administration may have transient effects on acoustic startle, sensorimotor gating, and peripheral brain-derived neurotrophic factor levels, and these changes may contribute to the adverse effects of opiate withdrawal. [ABSTRACT FROM AUTHOR]

Although certain drugs of abuse are known to disrupt brain glucose metabolism ( BGluM), the effects of opiates on BGluM are not well characterized. Moreover, preclinical positron emission tomography ( PET) studies anesthetize animals during the scan, which limits clinical applications. We investigated the effects of (i) isoflurane anesthesia and (ii) intravenous morphine self-administration ( MSA) on BGluM in rats. Jugular vein cannulated adult male Sprague-Dawley rats self-administered either saline ( SSA) or morphine (0.5 mg/kg/infusion, 4 h/day for 12 days). All animals were scanned twice with [18F]-fluoro-deoxy-glucose ( FDG)- PET/ CT at a baseline and at 2-day withdrawal from self-administration. After the IV injection of FDG, one batch of animals ( n = 14) was anesthetized with isoflurane and the other batch ( n = 16) was kept awake during the FDG uptake (45 min). After FDG uptake, all animals were anesthetized in order to perform a PET/ CT scan (30 min). Isoflurane anesthesia, as compared to the awake condition, reduced BGluM in the olfactory, cortex, thalamus, and basal ganglia, while increasing BGluM in the midbrain, hypothalamus, hippocampus, and cerebellum. Morphine self-administered animals exhibited withdrawal signs (piloerection and increased defecation), drug seeking, and locomotor stimulation to morphine (0.5 mg/kg) during the 2 day withdrawal. The BGluM in the striatum was increased in the MSA group as compared to the SSA group; this effect was observed only in the isoflurane anesthesia, not the awake condition. These findings suggest that the choice of the FDG uptake condition may be important in preclinical PET studies and increased BGluM in the striatum may be associated with opiate seeking in withdrawal. [ABSTRACT FROM AUTHOR]

Peterson's (2021) commentary on our recently published manuscript (Soumoff et al., 2021) suggests that our findings are an example of visible, physical injuries of war facilitating communication with others, which, in turn, fosters recovery from invisible war wounds. We agree that in the proper context, the retelling of one's traumatic story can be important for recovery from and, perhaps, even the prevention of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD). Participants in our study cohort differed frommost others who experienced combat trauma in that while they were hospitalized, they experienced nearly daily visits from a behavioral health provider to address traumatic stress-related symptoms. It is likely that individuals who sustained more severe physical injury (i.e., higher Injury Severity Score [ISS] ratings) had longer hospital stays, received more support, and had more opportunities to retell their stories than those with less severe injuries, leading to decreases in PTSD andMDDsymptoms. To note support of this supposition, in Table 5 of Soumoff et al. (2021), although not significant, the adjusted odds ratios (aORs) for PTSD and MDD were below 1 for service members with high (i.e., above 16) ISS ratings. The physical injury-related hospitalizations participants in our sample experienced fostered activities described by Peterson (2021) that likely contributed to the prevention and resolution of PTSD and MDD symptoms, benefits not received by most individuals who suffer only invisible wounds of war. [ABSTRACT FROM AUTHOR]