Deficits in docosahexaenoic acid and associated elevations in the metabolism of arachidonic acid and saturated fatty acids in the postmortem orbitofrontal cortex of patients with bipolar disorder

Previous antemortem and postmortem tissue fatty acid composition studies have observed significant deficits in the omega-3 fatty acid docosahexaenoic acid (DHA, 22:6n-3) in red blood cell (RBC) and postmortem cortical membranes of patients with unipolar depression. In the present study, we determined the fatty acid composition of postmortem orbitofrontal cortex (OFC, Brodmann area 10) of patients with bipolar disorder (n=18) and age-matched normal controls (n=19) by gas chromatography. After correction for multiple comparisons, DHA (-24%), arachidonic acid (-14%), and stearic acid (C18:0) (-4.5%) compositions were significantly lower, and cis-vaccenic acid (18:1n-7) (+12.5%) composition significantly higher, in the OFC of bipolar patients relative to normal controls. Based on metabolite:precursor ratios, significant elevations in arachidonic acid, stearic acid, and palmitic acid conversion/metabolism were observed in the OFC of bipolar patients, and were inversely correlated with DHA composition. Deficits in OFC DHA and arachidonic acid composition, and elevations in arachidonic acid metabolism, were numerically (but not significantly) greater in drug-free bipolar patients relative to patients treated with mood-stabilizer or antipsychotic medications. OFC DHA and arachidonic acid deficits were greater in patients plus normal controls with high vs. low alcohol abuse severity. These results add to a growing body of evidence implicating omega-3 fatty acid deficiency as well as the OFC in the pathoaetiology of bipolar disorder.     

Platelet kinetics in patients with atherosclerosis

In 12 patients (8 males, 4 females; 59.4 +/- 6.2 years) with clinically manifest atherosclerosis (peripheral vascular disease stage II according to Fontaine and coronary heart disease) without any risk factor and 6 controls (4 males, 2 females; 58.5 +/- 7.06 years) autologous platelets were labelled using 100 microCi 111-In-oxine. In parallel, serum- and plasma-thromboxane (TX) B2 and conversion of exogenous radiolabelled arachidonic acid towards TXB2 were determined. No difference in labelling efficiency and recovery was noted. Platelet half-life was significantly (p less than 0.01) shortened in the atherosclerotics. Gamma-camera images were obtained during the first 64 minutes after reinjection as well as 2, 6, 18, 24 and daily up to 1 week after reinjection of autologous radiolabelled platelets. No difference between the patients suffering from atherosclerosis--having either visible atherosclerotic lesions or not--could be discovered. Serum-TXB2 was comparable, whereas plasma-TXB2 showed a trend towards an increase and the conversion from exogenous 14C-AA to 14C-TXB2 was increased in atherosclerosis.     

The dexamethasone suppression test in a group of research diagnostic criteria schizoaffective depressed men

A dexamethasone suppression test (DST) was performed on 8 schizoaffective depressed men. Cross-sectional comparisons were made with three groups: schizophrenics (n = 10), unipolar major depressives (n = 23) and healthy controls (n = 43). All were drug-free and similar in age and body weight. Evaluations utilized the Research Diagnostic Criteria (RDC) for diagnosis, and the Hamilton Rating Scale for Depression for depressive symptom rating. DST nonsuppression, defined as a blood cortisol level of greater than or equal to 5.0 micrograms/dl at 16.00 h postdexamethasone, was observed in 43.5% of the major depressive disorder patients. This was different from the other three groups: 12.5% in schizoaffective depressed, 10.0% in schizophrenics and 9.3% in healthy controls (p less than 0.01, p less than 0.01, and p less than 0.001 respectively). Although schizoaffective depressed patients were significantly different from major depressive disorder patients in their DST responses, both groups were similar in their total HRSD scores and different from the schizophrenics (p less than 0.01 for each). These results, together with others previously reported by us on the thyrotropin-releasing hormone challenge in the same diagnostic groups, may be taken to mean that schizoaffective disorder, depressed type, is biologically distinct from major depressive disorder but not schizophrenia. On the other hand, until further corroborated, they should probably be considered a reflection of the heterogeneity of the schizoaffective syndrome and the nonspecificity of the DST.     

Detection of platelet desensitization in pregnancy-induced hypertension is dependent on the agonist used

The aggregation of platelets from women with pregnancy-induced hypertension (P.I.H.), or with normal pregnancies, in response to arachidonic acid, ADP, collagen or platelet activating factor (PAF) was examined. No differences in platelet aggregation between the normotensive and hypertensive women were detected when arachidonic acid or collagen were used to stimulate in vitro platelet aggregation. Higher concentrations of ADP and PAF were required to aggregate platelets from women with P.I.H. compared with platelets from normotensive controls. Platelets from women with normotensive pregnancies (n = 80) aggregated maximally in response to 20 nM PAF without exception. Reversible aggregation by platelets from women with P.I.H. (n = 25) was observed at the same concentration of PAF; again, this was found in all subjects tested. These results indicate that PAF at a concentration of 20 nM can clearly demonstrate differences in aggregation of platelets from women with normotensive pregnancy and women with P.I.H.     

The heritability of schizophrenia and schizoaffective disorder. A family study

Ninety-one consecutively admitted patients with schizophrenia (n = 21), schizoaffective depression (n = 43), or psychotic depression (n = 27) entered a blind family study along with 36 never-ill controls. Though schizophrenia spectrum disorders clustered within families, they were not significantly more prevalent in the families of schizophrenic probands. In contrast, morbid risks for affective disorder clearly separated the families of psychotically depressed probands from the families of both schizophrenics and controls. Family study data for schizoaffective probands indicated links to both affective disorder and schizophrenia and suggested, as well, that a small number of patients with schizoaffective disorder may carry a genetic liability to both conditions.     

Membrane fluidity and thromboxane synthesis in platelets from patients with severe atherosclerosis

Platelets play an important role in the development of atherosclerosis. The arachidonic acid, whose oxygenated metabolites are potent regulators of the platelet-vessel wall interactions, is released from membrane phospholipids by the phospholipase (s) system (s). These membrane-linked phenomena are strongly modulated by the membrane physical properties. The present study was carried out to investigate the relationship between membrane fluidity and arachidonic acid metabolism in platelets from atherosclerotic patients. Twenty-one patients with peripheral vascular disease and twelve controls were studied. Platelets from patients showed an increase in membrane fluidity and enhanced thrombin-stimulated thromboxane synthesis. No alterations were found, however, in total phospholipid fatty acid composition. A significant decrease in the cholesterol/phospholipid ratio could account for the alterations in the membrane physical properties described in the platelets from patients.     

Platelet arachidonic acid metabolism in severe cerebrovascular disease

The ability of platelets to synthetise thromboxane B₂ and hydroxylated fatty acids from arachidonic acid was studied simultaneously with arachidonic acid-induced aggregation in 42 patients suffering from severe cerebral atherosclerosis and also in 34 healthy controls. Additionally, phospholipase-A₂-induced aggregation was performed as a probe for arachidonic acid located at the platelet surface. All the assays were performed with washed platelets, eliminating a possible influence of plasma. Platelets from patients were found responsive to significantly lower concentrations of arachidonic acid whereas thromboxane and hydroxylated fatty acid biosynthesis did not differ from controls. In the experimental conditions used, 75% of the control platelets underwent aggregation with phospholipase A₂ plus sphingomyelinase C, in comparison to only 50% for the patients, indicating the necessity for further analysis of the platelet membrane lipids in atherosclerosis.     

Differential labeling of platelet alpha 2 adrenoceptors by 3H dihydroergocryptine and 3H yohimbine in patients with myeloproliferative disorders

Platelet alpha adrenoceptor status was examined using the radioligands 3H-yohimbine (3H-YOH) and 3H-dihydroergocryptine (3H-DHE) in 14 patients with myeloproliferative disorder (MPD) and 10 normal controls. Platelets from normal controls and MPD patients sensitive to adrenaline induced aggregation exhibited approximately 50% more binding sites identified by 3H-DHE than 3H-YOH, whereas MPD platelets insensitive to adrenaline showed selective loss of these 'extra' 3H-DHE sites. In functional studies after 30 minutes preincubation with the unlabelled antagonists, DHE was more potent than YOH at inhibiting adrenaline induced aggregation in normal platelets. In addition, the affinity constant for DHE was virtually identical in binding and functional experiments, whereas for YOH the affinity constant for binding was approximately 10 fold more potent than that for aggregation. These results suggest that the alpha adrenoceptor binding site on human platelets labelled by 3H-DHE may be of more functional relevance than that labelled by 3H-YOH alone.     

Cognitive impairments in schizophrenia and schizoaffective disorder: relationship with clinical characteristics

The present study aimed to compare population-based familial samples of patients with schizophrenia (n = 218) and schizoaffective disorder (n = 62) and a healthy control group (n = 123). Patients with schizoaffective disorder outperformed patients with schizophrenia in verbal ability, processing speed, visual working memory, and verbal memory. When compared with controls, patients with schizoaffective disorder also had a generalized cognitive impairment. Adjusting for clinical characteristics removed significant differences between the patient groups. Irrespective of the diagnosis, patients with the most severe negative symptoms and highest dose of antipsychotics had the most severe cognitive impairments, whereas mood symptoms were not related to cognitive performance. In conclusion, people with schizoaffective disorder have severe cognitive impairments, but the impairments are milder than in schizophrenia. Mood symptoms may not explain the difference between the diagnostic groups in cognitive functions, but the difference may be related to differences in the severity of negative symptoms.     

Low platelet apachidonic acid in young patients with brain infarction

Fatty acid patterns of plasma and platelet lipids, platelet aggregation and thromboxane A₂(TxA₂) production were studied in young patients (n = 12) with brain infarction and in healthy controls (n = 13). Platelet arachidonic acid content was significantly reduced in the stroke patients, but in vitro platelet aggregation was similar in the two groups. A low dose of acetosalicylic acid (ASA) (100 mg) suppressed thromboxane production and normalized the platelet arachidonic acid values. The low arachidonic acid in platelets is probably due to its increased consumption, indicating platelet activation in vivo.     

Clozapine for treatment-refractory schizophrenia, schizoaffective disorder, and psychotic bipolar disorder: a 24-month naturalistic study

BACKGROUND: The aim of this study was to evaluate the 24-month response to clozapine in patients with schizophrenia, schizoaffective disorder, or psychotic bipolar disorder. METHOD: Ninety-one psychotic patients with a principal DSM-III-R diagnosis of schizophrenia (N = 31), schizoaffective disorder (N = 26), or bipolar disorder with psychotic features (N = 34) were treated naturalistically with clozapine at flexible dosages over a 24-month period. Improvement was assessed by the 18-item Brief Psychiatric Rating Scale and the Clinical Global Impressions-Severity of Illness scale. RESULTS: All patients showed significant improvement 24 months from intake (p < .001). Such an improvement was significantly greater among patients with schizoaffective disorder or bipolar disorder than in patients with schizophrenia (p < .05). The presence of suicidal ideation at intake predicted greater improvement at endpoint. CONCLUSION: Clozapine appears to be effective and relatively well tolerated in acute and long-term treatment of patients with psychotic bipolar disorder or schizoaffective disorder who have not responded to conventional pharmacotherapies.     

The effect of plasma on platelet function in hypercholesterolemic rabbits and the changes in fatty acid composition of the plasma

Rabbits were fed with 1% cholesterol-containing standard diet for 1 to 3 months. The arachidonic acid (AA)-induced aggregation of the platelet-rich plasma (PRP) of the control rabbits was accelerated by substitution of hypercholesterolemic plasma. The incorporation of C-AA into thromboxane B₂ in platelets was increased approximately 1.6 times with PRP and 1.2 times with the washed platelet suspension (WPS) in hypercholesterolemic rabbits as compared with those of the control. Analysis of the fatty acid compositions of phospholipids and total lipids of hypercholesterolemic rabbits revealed an increase in AA of platelets and plasma, and a decrease in docosahexaenoic acid (DHA) in plasma. The AA/DHA ratio of plasma increased dependently on the period of feeding with the high cholesterol diet, and the increase in the ratio was parallel with the acceleration of platelet aggregation by AA in PRP.     

Increased thromboxane A2 generation and altered membrane fatty acid composition in platelets from patients with active angina pectoris

Lipid composition of platelet membranes and thromboxane A2 (TxA2) generation by platelets were investigated in eighty-seven anginal patients (forty-two with resting angina in active phase and forty-five with effort stable angina or rest angina in inactive phase) and in forty-five clinically healthy subjects of similar age. All subjects were on the same dietary regimen and the adherence to diet was checked by analysis of red blood cell lipids. Platelets from active angina patients produced more TxA2 than platelets from both inactive patients and controls (p less than 0.001). Moreover patients with active angina had higher arachidonic acid (AA, p less than 0.001) and lower eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) levels in phosphatidylcholine (PC, p less than 0.001), than inactive patients and controls. AA and EPA changes in membrane PC significantly correlated with TxA2 production (p less than 0.001) but not with coronary pathoanatomy. Plasma lipids, content of cholesterol, total phospholipids (and their saturated and unsaturated fatty acids) and the different phospholipid fractions in platelet membrane were not different in the three groups. Present results indicate that in platelets from anginal patients phospholipid fatty acid composition is at least in part independent of plasma composition and that in active angina there are modifications leading to increased TxA2 formation and possibly contributing to the occurrence of ischemic attacks.     

Measurement of the zeta potential of human platelets by the use of laser-light scattering.

An instrument was developed to detect the shift in scattering of laser light that occurs when particles in suspension move in a chamber with an electrical load. The instrument measures the zeta potential of particles. We applied the instrument to study human blood cells. Platelet-rich plasma was used because of the stability of the suspension, without the sedimentation or autoaggregation that is often seen with red or white blood cells. The reproducibility of the measurements was satisfactory when there were enough platelets in the suspension. Platelets from healthy controls (n = 136) had a potential of -14.20 +/- 1.64 mV at the detection angle of 17.1 degrees. Platelets from patients with essential thrombocytosis (n = 16) or polycythemia vera (n = 8) had higher potentials than the healthy controls.     

Hyperresponsiveness of platelets in ischemic stroke

Platelet activation and aggregation are critical in the pathogenesis of acute ischemic cerebrovascular diseases. The aim of our study was to characterize platelet function in patients with acute ischemic stroke or transient ischemic attack (TIA), and to evaluate the effect of platelet activation on clinical outcome. One hundred thirty-eight consecutive patients with TIA (n = 74) or stroke (n = 64) were enrolled in this study. Platelet aggregation in response to ADP, epinephrine, arachidonic acid, or collagen, and expression of platelet activation receptors (CD62P, CD63, LIBS-1 and PAC-1) in the acute phase and at three months follow-up were evaluated. Platelets derived from stroke patients were more hyperaggregable in response to agonists in the acute phase compared to TIA patients (p[ADP] = 0.002, p[arachidonic acid] = 0.047, p[epinephrine] = 0.020). Platelet activation was enhanced in the acute phase irrespective of the severity of the disease (stroke or TIA) and returned to baseline levels three months later. Persistent elevated platelet activation at three months follow-up (PAC-1) was associated with increased incidence of recurrent stroke (median, [interquartile range] 3.4, [3.0-5.2] versus 2.9, [2.3-4.0], p = 0.048). In conclusion, platelets are hyperactive in acute stroke compared with TIA. A more intensified dual antiplatelet therapy may be of benefit for stroke patients.     

Differential working memory impairment in bipolar disorder and schizophrenia: effects of lifetime history of psychosis

BACKGROUND: Although bipolar disorder and schizophrenia have long been viewed as distinct illnesses, there is growing evidence that these two complex diseases share some common genes, which may manifest as overlapping neuropsychological impairments. Although working memory dysfunction has been proposed to be central to the pathophysiology of schizophrenia, it has received less attention in studies of bipolar disorder. METHOD: We applied measures of working memory to patients with schizophrenia (n = 15), patients with schizoaffective disorder (n = 15), patients with psychotic (n = 11) and non-psychotic (n = 15) bipolar disorder, and demographically matched healthy subjects (n = 32), in order to determine the extent to which these groups show common or unique impairments. RESULTS: While patients with bipolar disorder (with and without psychotic features) and those with schizophrenia/schizoaffective disorder were impaired on backward digit span, only patients with a lifetime history of psychotic features, regardless of diagnosis, were impaired on spatial delayed response task. CONCLUSIONS: Backward digit span performance is comparable in bipolar disorder and schizophrenia, and may be an appropriate endophenotypic marker that cuts across diagnostic categories. In contrast, spatial working memory performance clearly distinguishes non-psychotic bipolar disorder patients from patients with functional psychosis.     

Gating of a novel brain potential is associated with perceptual anomalies in bipolar disorder

Patterson JV, Sandman CA, Jin Y, Kemp AS, Potkin SG, Bunney WE Jr. Gating of a novel brain potential is associated with perceptual anomalies in bipolar disorder.
Bipolar Disord 2013: 00: 000–000. © 2013 John Wiley & Sons A/S.Published by Blackwell Publishing Ltd. Objectives: Our laboratory recently identified the P85 gating ratio as a candidate biomarker for bipolar disorder. In order to evaluate the phenomenological significance of P85 gating, the current study examined reports of perceptual anomalies and their relationship to the P50 and P85 physiological measures of sensory gating. Methods: Reports of perceptual anomalies on the Structured Clinical Interview to Assess Perceptual Anomalies were compared in patients meeting DSM‐IV criteria for paranoid schizophrenia (n = 66), schizoaffective disorder (n = 45), or bipolar I disorder (n = 42), and controls (n = 56), as well as their relationship with P85 and P50 gating. Results: The bipolar disorder group reported significantly more auditory, visual, and total anomalies than both the schizophrenia and control groups. The schizophrenia group also had more anomalies than the control group. Comparison of psychiatric subgroups revealed that the bipolar depressed, bipolar disorder with psychosis, and schizoaffective bipolar type groups reported the most anomalies compared to the other patient groups (bipolar disorder without psychosis, schizoaffective, bipolar manic). The total perceptual anomalies score and the P85 ratio significantly differentiated the bipolar disorder, schizoaffective, and paranoid schizophrenia groups from each other. Conclusions: These findings provide evidence of the phenomenological significance of P85. The results also yield further support not only for the P85 ratio, but also for increased reports of perceptual anomalies as possible markers for bipolar disorder.     

Obstetric complications in schizophrenia, schizoaffective disorder and normal comparison subjects

Previous studies have indicated that obstetric complications (OCs) may be risk factors for schizophrenia, but findings are inconsistent, and data about other diagnostic groups are relatively scarce. We compared the obstetric histories of subjects with schizophrenia, major affective disorder and normal controls. Our subjects included 61 schizophrenia, 26 schizoaffective, 28 major affective disorder patients and 21 normal controls. OCs were rated on the McNeil–Sjöström Scale using data from mothers reports and for a subsample from hospital and birth certificate records. The frequency of OCs did not differ statistically between diagnostic groups at any stage or for the three stages combined. OCs of at least level 4 were found in 69% of schizophrenia patients, 62% of schizoaffective patients, 68% of major affective disorder patients and 71% of the normal comparison group. OCs of at least level 5 were found in 23% of schizophrenia patients, 23% of schizoaffective patients, 21% of the major affective disorder patients and 14% of the normal comparison group. Our findings indicate that the etiologic significance of OCs may not be specific to schizophrenia.     

Erythrocyte sodium pump activity in bipolar affective disorder and other psychiatric disorders

Erythrocyte ouabain-inhibitable sodium pump activity, a measure of NaK-ATPase activity, was studied in 6 diagnostic groups of psychiatric subjects: bipolar affective disorder, unipolar depressive disorder, neurotic depression, chronic alcohol abuse, schizoaffective disorder, and schizophrenia, and in sex- and age-matched normal controls. In the bipolar manic-depressive group, which was restricted to lithium-free subjects, values for sodium pump activity were significantly lower than in the controls (-11.4%, n = 53, p less than 0.001); subgrouping of the bipolar group by sex or age showed a significantly lower sodium pump activity in each of the groups. In the unipolar depressive group, values for sodium pump activity were significantly higher than in the controls (+13.7%, n = 12, p less than 0.01). The difference in direction of changed sodium pump activity between the bipolar and the unipolar groups was also observed in the values for subgroups of subjects in the two categories who were in a depressed state at the time the blood sample was taken. In the chronic alcohol abuse group, values for sodium pump activity were significantly higher than those for the control group (+13.5%, n = 20, p less than 0.05). In the neurotic depression (n = 24), schizoaffective (n = 12), and schizophrenia (n = 35) groups, there were no significant differences in sodium pump activity between the group of psychiatric subjects and their matched controls. These observations indicate that there is a trait-dependent deficiency of NaK-ATPase activity in bipolar affective disorder.     

The effect of aspirin on the size of the hemostatic plug

The prolongation of the bleeding time by aspirin is presumably due to interfering with platelet function. Direct quantitative studies evaluating the effects of aspirin on the platelet component of the hemostatic plug have not been described. We measured blood loss from a standard ear injury in rabbits after treatment with either 5 mg or 200 mg/kg of aspirin (ASA) or sodium salicylate (SA), and related this observation to the number of platelets incorporated into the hemostatic plug. The high dose of aspirin was chosen since this dose inhibits PGI2 biosynthesis. Both doses of aspirin but not salicylate caused a significant increase on blood loss from the treated ear compared to the control (ASA 5 mg/kg, 0.012 +/- 0.009 ml, (m +/- SE), n = 44, p = 0.03; ASA 200 mg/kg, 0.02 +/- 0.007 ml, n = 17, p less than 0.05). Both doses of aspirin also caused a significant increase in the number of platelets incorporated into the hemostatic plug when compared to the SA treated animals (ASA 5 mg/kg, 3.52 +/- 0.34 X 10(6) platelets per incision, (m +/- SE), n = 59; SA 5 mg/kg, 1.9 +/- 0.15 X 10(6) platelets per incision, n = 54, p less than 0.001; ASA 200 mg/kg, 3.19 +/- 0.54 X 10(6) platelets per incision, n = 22; SA 200 mg/kg, 1.5 +/- 0.26 X 10(6) platelets per incision, n = 23, p less than 0.001). This study suggests that following aspirin administration hemostasis is achieved by the incorporation of a greater number of platelets into the platelet plug.(ABSTRACT TRUNCATED AT 250 WORDS)