Alternatively Spliced Genes as Biomarkers for Schizophrenia, Bipolar Disorder and Psychosis: A Blood-Based Spliceome-Profiling Exploratory Study.

OBJECTIVE: Transcriptomic biomarkers of psychiatric diseases obtained from a query of peripheral tissues that are clinically accessible (e.g., blood cells instead of post-mortem brain tissue) have substantial practical appeal to discern the molecular subtypes of common complex diseases such as major psychosis. To this end, spliceome-profiling is a new methodological approach that has considerable conceptual relevance for discovery and clinical translation of novel biomarkers for psychiatric illnesses. Advances in microarray technology now allow for improved sensitivity in measuring the transcriptome while simultaneously querying the "exome" (all exons) and "spliceome" (all alternatively spliced variants). The present study aimed to evaluate the feasibility of spliceome-profiling to discern transcriptomic biomarkers of psychosis. METHODS: We measured exome and spliceome expression in peripheral blood mononuclear cells from 13 schizophrenia patients, nine bipolar disorder patients, and eight healthy control subjects. Each diagnostic group was compared to each other, and the combined group of bipolar disorder and schizophrenia patients was also compared to the control group. Furthermore, we compared subjects with a history of psychosis to subjects without such history. RESULTS: After applying Bonferroni corrections for the 21,866 full-length gene transcripts analyzed, we found significant interactions between diagnostic group and exon identity, consistent with group differences in rates or types of alternative splicing. Relative to the control group, 18 genes in the bipolar disorder group, eight genes in the schizophrenia group, and 15 genes in the combined bipolar disorder and schizophrenia group appeared differentially spliced. Importantly, thirty-three genes showed differential splicing patterns between the bipolar disorder and schizophrenia groups. More frequent exon inclusion and/or over-expression was observed in psychosis. Finally, these observations are reconciled with an analysis of the ontologies, the pathways and the protein domains significantly over-represented among the alternatively spliced genes, several of which support prior discoveries. CONCLUSIONS: To our knowledge, this is the first blood-based spliceome-profiling study of schizophrenia and bipolar disorder to be reported. The battery of alternatively spliced genes and exons identified in this discovery-oriented exploratory study, if replicated, may have potential utility to discern the molecular subtypes of psychosis. Spliceome-profiling, as a new methodological approach in transcriptomics, warrants further work to evaluate its utility in personalized medicine. Potentially, this approach could also permit the future development of tissue-sampling methodologies in a form that is more acceptable to patients and thereby allow monitoring of dynamic and time-dependent plasticity in disease severity and response to therapeutic interventions in clinical psychiatry.

Candidate genes, pathways and mechanisms for bipolar (manic-depressive) and related disorders: an expanded convergent functional genomics approach.

Identifying genes for bipolar mood disorders through classic genetics has proven difficult. Here, we present a comprehensive convergent approach that translationally integrates brain gene expression data from a relevant pharmacogenomic mouse model (involving treatments with a stimulant--methamphetamine, and a mood stabilizer--valproate), with human data (linkage loci from human genetic studies, changes in postmortem brains from patients), as a bayesian strategy of crossvalidating findings. Topping the list of candidate genes, we have DARPP-32 (dopamine- and cAMP-regulated phosphoprotein of 32 kDa) located at 17q12, PENK (preproenkephalin) located at 8q12.1, and TAC1 (tachykinin 1, substance P) located at 7q21.3. These data suggest that more primitive molecular mechanisms involved in pleasure and pain may have been recruited by evolution to play a role in higher mental functions such as mood. The analysis also revealed other high-probability candidates genes (neurogenesis, neurotrophic, neurotransmitter, signal transduction, circadian, synaptic, and myelin related), pathways and mechanisms of likely importance in pathophysiology.

Relationship of gender and age at onset of schizophrenia to severity of dyskinesia.

The authors examined severity of dyskinesia in 119 men and 44 women, comparing by gender those with late-onset schizophrenia (LOS) versus early-onset schizophrenia (EOS). Women with LOS and men with EOS had more severe dyskinesia than men with LOS and women with EOS. Many factors, including the length of neuroleptic treatment, alcohol and smoking history, and menopausal status, may contribute to the severity of dyskinesia in older patients with schizophrenia.

Hormone replacement therapy in postmenopausal women with schizophrenia: positive effect on negative symptoms?

BACKGROUND: Some studies of premenopausal women suggest that the severity of psychopathology associated with schizophrenia may be related to levels of estrogen. METHODS: We examined psychopathology in community-dwelling postmenopausal women with schizophrenia who had received (n = 24) versus had never received (n = 28) hormone replacement therapy. RESULTS: Users of hormone replacement therapy and nonusers did not differ significantly with respect to age, ethnicity, education, age of onset, duration of schizophrenia, global cognitive functioning, or neuroleptic-induced movement disorders. The hormone replacement therapy users received lower average daily doses of antipsychotic medication; they had similar levels of positive symptoms but significantly less severe negative symptoms compared with hormone replacement therapy nonusers, independent of differences in antipsychotic dosage. CONCLUSIONS: Our results suggest that the use of hormone replacement therapy in conjunction with antipsychotic medication in postmenopausal women with schizophrenia may help reduce negative, but not positive, symptoms.

The role of psychiatrists in primary care of patients with severe mental illness.

OBJECTIVE: This study sought to identify health conditions for which a primary care psychiatrist would be an appropriate treatment provider in an integrated model of health care delivery for persons with serious mental illness. A primary care psychiatrist is a psychiatrist with primary care training who is supervised by an on-site internist. METHODS: Rating methods for health conditions were adapted from those jointly developed by Rand and the University of California, Los Angeles. A consensus panel of 14 hospital administrators, internists, psychiatrists, and nursing service representatives from three southern California Veterans Affairs health care systems was convened. Eleven physician-panelists, including five psychiatrist, five internists, and a medical specialist, rated whether a general psychiatrist, a primary care psychiatrist, an internist, or a medical specialist could reasonably provide evaluation, treatment, or preventive care for uncomplicated instances of each of 344 physical health conditions or procedures. RESULTS: A primary care psychiatrist, with supervision by an internist, was rated as an appropriate treatment provider for most of the 344 conditions. The conditions included many of those cited by patients as the most common reasons for ambulatory care visits. Panelists identified some intrusive elements of primary care, such as a pelvic examination, as potentially injurious to the psychiatrist-patient relationship and inappropriate for performance by psychiatrists. CONCLUSIONS: This study took the first essential step in evaluating the integration of primary care into the psychiatric setting. Further research is needed to determine whether use of primary care psychiatrists will increase access to primary care by persons with serious mental illness and improve outcomes.

Neuroleptic-induced striatal damage in rats: a study of antioxidant treatment using accelerometric and immunocytochemical methods.

RATIONALE: Investigators have postulated that neuroleptic medications may affect the motor system through the creation of free radicals. Also, structural brain changes related to oxidative damage may disrupt normal striatal function. OBJECTIVE: The goals of this study were to examine whether an antioxidant diet reduced the abnormal movements caused by long-term neuroleptic exposure and to examine structural effects within specific striatal regions in rats. METHODS: Rats were given a basal diet or a diet high in antioxidants for 4 months, and treated with 10 mg/kg fluphenazine decanoate or sesame seed oil IM every 2 weeks. At baseline and after treatment, head movements were quantified by accelerometry, and immunocytochemically stained cholinergic neurons in the ventrolateral, mediodorsal, and ventromedial regions of the striatum were quantified. RESULTS: Rats treated with fluphenazine had significantly lower neuron densities than those that did not receive antioxidants. Rats exposed to a diet consisting of antioxidants had significantly higher neuron densities than those that did not receive antioxidants in each of the three regions tested. Rats treated with fluphenazine had a greater increase in the number of accelerometric peaks recorded per minute compared with untreated animals. The increase in the number of accelerometric peaks recorded per minute was lower for animals exposed to antioxidant diets compared with unexposed animals. Lastly, there was a significant correlation between the accelerometric peak change score and cholinergic neuron density in all three regions. CONCLUSIONS: Our results suggest that long-term neuroleptic treatment is associated with an increase in head movements and a reduction in ChAT-stained striatal cholinergic neurons and that these abnormalities are reduced by antioxidants.

Gender-related clinical differences in older patients with schizophrenia.

BACKGROUND: Gender differences in the clinical presentation of young patients with schizophrenia have been well-documented, yet few studies have investigated gender-related clinical differences in older patients. Furthermore, the symptoms of late-onset schizophrenia have been described, but the interaction between gender and age at onset has not been examined. METHOD: In an older (46-85 years of age) outpatient sample, we assessed clinical characteristics of women and men with early-onset schizophrenia (N = 90) and late-onset schizophrenia (N = 34). Subjects did not differ with respect to age, education, ethnicity, severity of depression, daily neuroleptic dosage, subtype of schizophrenia, total score on the Mini-Mental State Examination, or severity of overall psychopathology. Diagnosis was made using the Structured Clinical Interview for the DSM-III-R or DSM-IV. RESULTS: A significantly greater proportion of women had late-onset schizophrenia (41% vs. 20%), and women overall had more severe positive psychotic symptoms. Although there was no overall gender difference in severity of negative psychotic symptoms, women with late onset had significantly less severe negative symptoms than men with early onset, men with late onset, and women with early onset. Furthermore, age at onset of schizophrenia was inversely correlated with severity of negative symptoms for women, but not for men. These results indicate that women overall may develop more severe positive symptoms than men, and that when women develop schizophrenia after age 45, they may suffer less severe negative symptoms than men or than women with earlier onset. Our results suggest that some of the clinical differences between late-onset and early-onset schizophrenia may relate to gender effects, and that there may be inherent differences in the clinical presentation of schizophrenia that are related to gender and gender by age at onset interactions. CONCLUSION: These differences may reflect the influence of sex hormones and menopause on the clinical presentation of schizophrenia or the possible existence of an "estrogen-related" form of schizophrenia in women with late-onset schizophrenia.

Comparison of outcomes of acute care in short-term residential treatment and psychiatric hospital settings.

OBJECTIVE: The study compared the demographic and diagnostic characteristics of clients and the outcomes of treatment in five short-term acute residential treatment programs and two acute hospital-based psychiatric programs. METHODS: A total of 368 clients in the short-term acute residential treatment programs and 186 clients in the psychiatric hospital programs participated in an observational study. The study used a repeated-measures design and assessed participants on multiple standardized measures of symptoms and functioning at admission, discharge, and four-month follow-up. Comparisons between the two groups were conducted separately by diagnostic category. Measures included the Brief Symptom Inventory, the Behavior and Symptom Identification Scale-32, the Medical Outcomes Short-Form-36, and the Client Satisfaction Questionnaire-8. RESULTS: The two types of programs admit persons with similar levels of acute distress who have comparable levels of improvement at discharge and an equivalent degree of short-term stability of treatment gains. Costs of treatment episodes were considerably lower for the short-term residential programs, and client satisfaction with the two types of programs was comparable. CONCLUSIONS: Short-term acute residential treatment is a less costly yet similarly effective alternative to psychiatric hospitalization for many voluntary adult patients.

Conventional vs. newer antipsychotics in elderly patients.

Elderly patients with schizophrenia and dementia patients with agitation are frequently candidates for antipsychotic treatment. Conventional neuroleptics have relatively little effect on negative symptoms and may cause considerable side effects, especially in elderly patients. The authors have found a 29% cumulative annual incidence of tardive dyskinesia (TD) in middle-aged and elderly outpatients treated with relatively low doses of conventional neuroleptics Newer antipsychotics are less likely to cause extrapyramidal symptoms and may be associated with a lower risk of TD. They are generally effective for both positive and negative symptoms and may also improve some aspects of cognition, but these drugs have their own side effects. Dosing requirements for elderly patients tend to be much lower than those for younger adults.

Adverse neurobiological effects of long-term use of neuroleptics: human and animal studies.

Neuroleptics have revolutionized the treatment of schizophrenia and other psychoses since the early 1950s. Several adverse neurobiological effects are, however, associated with the long-term use of these agents. This article will review human and animal studies of these adverse effects, and also present some new data. Tardive dyskinesia (TD) is the most widely studied potentially persistent movement disorder resulting from long-term neuroleptic treatment, and several risk factors for TD development have been identified. Although drug-induced parkinsonism (DIP) usually disappears after the offending agent is withdrawn, a small portion of patients may have persistent parkinsonism. It is however, unclear if this is an aging-related effect. Persistent cognitive impairment associated with long-term use of typical neuroleptics has not been well documented. Atypical antipsychotics may produce improvement in cognitive performance in patients with chronic schizophrenia. MRI changes that are secondary to neuroleptics are possible, but have not yet been studied adequately. There is one unconfirmed report of neurofibrillary tangles associated with long-term neuroleptic use. A number of investigators have reported vacuous chewing movements, and neuropathologic changes following prolonged administration of neuroleptics in animals. We discuss the implications of the various reported adverse effects of long-term use of neuroleptics.

Scaling of movement velocity: a measure of neuromotor retardation in individuals with psychopathology.

The study of motor slowness based on observational methods has limitations. Whether motor retardation has a psychomotor or neuromotor basis is unclear because psychiatric and motor symptoms overlap. Observational methods lack the precision necessary to distinguish cognitive from motor processes. For the present study, we used an objective measure of neuromotor dysfunction to quantify the extent to which an individual programs movement velocity in anticipation of increasing target distance. Persons with Parkinson's disease (PD) or functional psychosis were studied with a group of healthy comparison subjects. Results indicated that the slope of the linear function relating velocity to distance was abnormal in the PD group and in approximately half of the psychosis group. Analyses revealed the measure to have high specificity and sensitivity. Weak correlations between velocity scaling and psychopathology support the neuromotor basis of the measure. We conclude that this measure of velocity scaling is relatively uninfluenced by cognitive factors that may underlie psychomotor retardation.

Minor physical anomalies in older patients with late-onset schizophrenia, early-onset schizophrenia, depression, and Alzheimer's disease.

The authors assessed five groups of older subjects (age > 45) for evidence of minor physical anomalies. The groups were patients with early-onset schizophrenia (onset at age < 45; n = 15), late-onset schizophrenia (onset at age > 45; n = 8), Alzheimer's disease (AD; n = 11), and unipolar depression (n = 11), and normal comparison (NC) subjects (n = 15). Patients with late- and early-onset schizophrenia, and unipolar depression were found to have significantly more anomalies than NC subjects. Patients with AD did not have significantly more anomalies than NC subjects, although the patients with AD were significantly older than the NC subjects. The authors discuss implications of these findings on the pathophysiology of schizophrenia.

An association between increased serum-soluble interleukin-2 receptors and a disturbance in muscle force in schizophrenic patients.

1. Serum-soluble interleukin-2 receptors (SIL-2Rs), a sign of immune activation, are increased in approximately 30% of schizophrenic subjects. 2. In a recent publication the authors found that SIL-2Rs were particularly elevated in schizophrenic subjects with tardive dyskinesia (TD). 3. This paper investigates the relationship between muscle force instability and SIL-2Rs in 32 schizophrenic patients, 10 of whom were neuroleptic-naive. 4. The authors hypothesized that there would be a positive correlation between increased levels of SIL-2Rs and muscle force instability. 5. Serum SIL-2Rs and muscle force instability were positively correlated (r = 0.54, p < .001) in the schizophrenic patients, and this correlation held even for the subset of neuroleptic-naive patients (r = .73, df 8, p = .016). 6. These findings suggest that there is an important correlation between immune activation and muscle force instability in schizophrenic patients.

Reliability of an instrumental assessment of tardive dyskinesia: results from VA Cooperative Study #394.

Nine VA Medical Centers are participating in a 2-year double-blind placebo controlled study of antioxidant treatment for tardive dyskinesia (TD) conducted by the Department of Veteran Affairs Cooperative Studies Program. One of the principal outcome measures of this study is the score derived from the instrumental assessment of upper extremity dyskinesia. Dyskinetic hand movements are quantified by assessing the variability associated with steady-state isometric force generated by the patient. In the present report, we describe the training procedures and results of a multi-center reliability assessment of this procedure. Data from nine study centers comprising 45 individual patients with six trials each (three from left hand and three from right hand) were reanalyzed by an independent investigator and the results were subjected to reliability assessment. For the statistic of interest (average coefficient of variation over trials 2 and 3 for each hand, then take the larger of these two values), we found very high intraclass correlation coefficients for reliability over all patients across sites (ICC = 0.995). We also calculated the reliability of the measures across trials within patient for each combination of hand (right, left, dominant), rater group (site, control), and trials set (all three, trials 2 and 3). For a given hand and trial set, the reliability of the site raters was similar to that of the control. This study demonstrates that instrumental measures for the assessment of dyskinesia are reliable and can be implemented in multi-center studies with minimal training.

Protein phosphorylation changes ligand-binding efficiency of cytochrome P450c17 (CYP17) and accelerates its proteolytic degradation: putative relevance for hormonal regulation of CYP17 activity.

Two novel mechanisms of protein kinase function in the complex gonadotropic regulation of the bifunctional cytochrome P450c17 (CYP17), the rate-limiting enzyme of androgen synthesis within the smooth endoplasmic reticulum of gonadal endocrine cells, are reported. In microsomal membranes from rat testes, the maximal type I optical difference spectrum induced by the physiological CYP17 substrate, progesterone, as a measure of spin state transition due to hydrophobic ligand-protein interaction is enhanced by 24% within 15 minutes in the presence of MgATP; the dissociation constant decreases from 71 to 43 nM. Testicular cytosol does not modify this effect which is completely abolished by the protein kinase inhibitor, bisindolylmaleimide, and which does not occur with ketoconazole as ligand. Furthermore, CYP17 degradation by cytosolic protease(s) is 2.5-fold accelerated by ATP; this action is completely reversed by the protein kinase inhibitors bisindolylmaleimide (half-maximal protective concentration 2.04 microM) and KT5720 (99 nM). The former compound also prevents human choriogonadotropin-induced testicular CYP17 inactivation in situ. It is concluded that protein kinase A-catalyzed target phosphorylation integrates the known biphasic steroidogenic response upon hormonal stimulation by initial improvement of substrate accommodation followed by counter-regulatory promotion of CYP17 proteolysis.

Gender, estrogen, and schizophrenia.

Most of the evidence to support an association between estrogen and psychosis is indirect and comes from clinical studies of gender differences in schizophrenia and from studies of fluctuating levels of psychopathology in different phases of the menstrual cycle. Our data, as well as those of other investigators, suggest a significantly later age at onset of schizophrenia in women than in men. There is somewhat more direct evidence from animal studies indicating that estrogen modulates dopamine systems in a manner similar to neuroleptics, although there are some inconsistencies in the literature. Few studies have examined the effects of estrogen administration in conjunction with neuroleptics on psychotic symptoms. We present a case report of a postmenopausal women with schizophrenia who had an improvement in positive symptoms with estrogen replacement therapy. Long-term double-blind treatment studies are needed to investigate the effects of estrogen on psychotic symptoms in women with schizophrenia.

Lateralized hemispheric dysfunction in the major psychotic disorders: historical perspectives and findings from a study of motor asymmetry in older patients.

Differences in functioning between the two cerebral hemispheres have been reported for more than a century. In recent decades, issues related to lateralized dysfunction have been raised in psychiatric illnesses such as schizophrenia and bipolar disorder. In particular, evidence suggests that schizophrenia may be particularly associated with left hemisphere dysfunction and bipolar disorder with right hemisphere dysfunction. We discuss these issues, along with a conceptual framework for integrating hypotheses about the relationship between the major psychotic illnesses based on a two-dimensional continuum. We also present new findings from our study of motor asymmetry in older patients with psychosis that support this framework. Our results indicate that schizophrenia may be associated with left hemisphere pathology to a greater extent than right, whereas the reverse may occur in bipolar disorder.

Instrumental motor predictors of neuroleptic-induced parkinsonism in newly medicated schizophrenia patients.

Previous studies suggest that many untreated schizophrenia patients exhibit motor disturbances. On the basis of these findings, the authors hypothesized that preexisting extrapyramidal movement disorders may increase the risk of developing neuroleptic-induced parkinsonism (NIP). Thirty-five newly medicated psychotic patients underwent pretreatment clinical and instrumental motor and psychiatric assessments. Posttreatment ratings of parkinsonism were conducted at monthly intervals for the first 3 months and every 3 months thereafter. Thirteen patients (37%) developed NIP. Advanced age and pretreatment extrapyramidal disturbances predicted NIP. Life-table survival curves indicated that patients with pretreatment instrumental rigidity developed clinically significant NIP earlier than those without rigidity. These findings suggest that pretreatment motor dysfunction may be a risk factor for drug-induced parkinsonism, especially among older patients.

Ligand dependence of cytochrome P450c17 protection against proteolytic inactivation: structural, methodological and functional implications.

Rate constants for the subtilisin-catalyzed proteolytic inactivation of cytochrome P450c17 (CYP17), the endoplasmic reticulum membrane-bound limiting enzyme of gonadal androgen synthesis, have been determined in the absence and presence of various CYP17 ligands and correlated with fractional enzyme saturation (Y). Extrapolation to Y = 1 reveals 15.1-, 4.0- and 7.4-fold enzyme stabilization with progesterone (substrate-type ligand), testosterone (product-type ligand) and ketoconazole (imidazole-type inhibitory ligand), respectively. Structural features of ligand accommodation can therefore be monitored by the susceptibility of target enzymes to proteolysis. It is further proposed that specific protection of a membrane protein by ligand binding during proteolytic digestion may assist in the purification of that protein. Evidence is finally presented that the gonadotropin-induced rapid CYP17 down-regulation is not promoted by an elevation of steroid hormone levels.