Platelet serotonin and plasma prolactin and cortisol in healthy, depressed and schizophrenic women

Cortisol in schizophrenia spectrum disorders: A comprehensive meta-analysis

Schizophrenia spectrum disorders (SSD) are characterized by alterations in cortisol levels across various parameters, including stress reactivity, hair cortisol, and baseline levels, which may be influenced by antipsychotic treatment. To provide a comprehensive overview of cortisol dysregulation in SSD, we conducted meta-analyses assessing (1) the effects of antipsychotic treatment in SSD patients, and additionally comparing cortisol in SSD patients versus healthy controls (HC) (2) following stress induction (metabolic, physiological, psychological stressors), (3) in hair and (4) baseline levels. Systematic literature searches in PubMed, Web of Science, and PsycINFO (November 2024) identified 121 studies (9049 SSD patients) for inclusion. Meta-analytic results revealed that antipsychotic treatment significantly reduced cortisol levels in SSD (k = 16, g = -0.480, 95 % CI [-0.818, -0.142], p = 0.005). Additionally, compared to HC, SSD was associated with reduced cortisol suppression following dexamethasone exposure (k = 9, g = 0.299, 95 % CI [0.091, 0.507], p = 0.005) and with elevated baseline cortisol levels in the morning (k = 71, g = 0.38, 95 % CI [0.210, 0.546], p < 0.001) and evening (k = 11, g = 0.368, 95 % CI [0.076, 0.661], p = 0.014). However, there were no significant group differences in afternoon baseline cortisol, hair cortisol or cortisol reactivity to stress (p > 0.05). These findings offer a detailed understanding of cortisol alterations in SSD and improve our understanding of HPA axis dysregulation in SSD.

Peripheral platelet count is a diagnostic marker for predicting the risk of rapid ejaculation: findings from a pilot study in rats

ABSTRACT

Parameters of peripheral blood cell have been shown as the potential predictors of erectile dysfunction (ED). To investigate the clinical significance of hematological parameters for predicting the risk of rapid ejaculation, we established a rat copulatory model on the basis of ejaculation distribution theory. Blood samples from different ejaculatory groups were collected for peripheral blood cell counts and serum serotonin (5-HT) tests. Meanwhile, the relationship between hematological parameters and ejaculatory behaviors was assessed. Final analysis included 11 rapid ejaculators, 10 normal ejaculators, and 10 sluggish ejaculators whose complete data were available. The platelet (PLT) count in rapid ejaculators was significantly lower than that in normal and sluggish ejaculators, whereas the platelet distribution width (PDW) and mean platelet volume (MPV) were significantly greater in rapid ejaculators. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis showed that the PLT was an independent protective factor for rapid ejaculation. Meanwhile, rapid ejaculators were found to have the lowest serum 5-HT compared to normal and sluggish ejaculators ( P < 0.001). Furthermore, there was a positive correlation between the PLT and serum 5-HT ( r = 0.662, P < 0.001), indicating that the PLT could indirectly reflect the serum 5-HT concentration. In addition, we assessed the association between the PLT and ejaculatory parameters. There was a negative correlation between ejaculation frequency (EF) and the PLT ( r = -0.595, P < 0.001), whereas there was a positive correlation between ejaculation latency (EL) and the PLT ( r = 0.740, P < 0.001). This study indicated that the PLT might be a useful and convenient diagnostic marker for predicting the risk of rapid ejaculation.

Nonlinear study of indolamines: A hidden property that might have possible implications in neurodegeneration

Indolamines (e.g., serotonin and melatonin) are tryptophan-derived class of neurotransmitters and neuromodulators that play crucial roles in mood regulation, sleep-wake cycles, and gastrointestinal functions. These biogenic amines exert their effects by binding to specific receptors in the central nervous system, influencing neuronal activity and signalling cascades. Indolamines are vital in maintaining homeostasis, and imbalances in their levels have been implicated in various neurological and psychiatric disorders. Hence, in the present study, we have investigated the nonlinear properties of indolamines under a continuous wave (CW) and pulsed laser excitation using the closed-aperture (CA) Z-scan technique. The CA Z-scan is a cost-effective and sensitive analytical tool for investigating nonlinear properties. It is observed that indolamines show negative refractive and positive absorptive nonlinearity under in vitro physiological conditions. The origin of nonlinearity is ascribed to the thermo-optical effect governed by the saturated atomic absorption and molecular orientation mechanisms under CW and pulsed laser excitation, respectively. The strength of nonlinearity is found to vary linearly with the concentration of indolamines. Overall, serotonin possesses stronger nonlinearity than melatonin. The maximum nonlinearity (refractive index (n2) & absorption coefficient (β)) for melatonin under CW and pulsed laser excitations are (-1.266 × 10-12 m2W-1 and -1.883 × 10-17 m2W-1) & (8.046 × 10-8 mW-1 and 1.516 × 10-13 mW-1), respectively. Meanwhile, the maximum n2 and β under pulsed laser excitation for serotonin are obtained as -3.195 × 10-17 m2W-1 and 6.149 × 10-12 mW-1, respectively. The outcome of the results may be utilized in understanding processes mediated by indolamines and designing therapeutic interventions.

The Mini-TRH Test

Thyrotropin-releasing hormone (TRH), at doses lower than those needed to stimulate prolactin secretion directly, can almost completely antagonize dopamine inhibition of prolactin release. In normal men, prolactin increases 15 min following an i. v. bolus of 12.5 µg TRH (the mini-TRH test), but not the maximal prolactin response to TRH or basal prolactin, positively correlated with prolactin response to haloperidol and negatively with 24-h urinary excretion of homovanillic acid (HVA). These results suggest that the mini-TRH test is a better estimate of dopamine inhibition of prolactin release than the maximal prolactin response or basal prolactin level. A recent neuroimaging study suggested that in schizophrenia, there is a widely distributed defect in extrastriatal dopamine release, but the patients were not in the most acute phase of psychosis. The evidence is reviewed that this defect extends to tuberoinfundibular dopamine (TIDA) and which symptoms are associated with the test. In patients with acute nonaffective psychosis, the mini-TRH test positively correlated with nonparanoid delusions and memory dysfunction, indicating decreased dopamine transmission in association with these symptoms. In patients with acute drug-naïve first-episode schizophrenia, the mini-TRH test negatively correlated with negative disorganization symptoms and with basal prolactin. The latter correlation suggests the contribution of factors related to maximal prolactin stimulation by TRH; therefore, an alternative dose of 6.25 μg TRH could be used for the mini-TRH test in first-episode patients, allowed by increased sensitivity of the present prolactin tests. Future studies are needed to investigate whether the mini-TRH test could help in finding the optimal antipsychotic medication.

Serum cortisol and insulin-like growth factor 1 levels in major depressive disorder and schizophrenia

The pathophysiology underlying major depressive disorder (MDD) and schizophrenia is related to endocrine system functions and includes changes in the blood levels of cortisol and insulin-like growth factor 1 (IGF-1). However, these hormones have not been investigated simultaneously in patients with MDD and schizophrenia. We investigated the differences in serum cortisol and IGF-1 levels among patients with MDD and schizophrenia and controls. We included 129 patients with MDD, 71 patients with schizophrenia, and 71 healthy volunteers. Blood tests were performed between 6:00 am and 11:00 am after fasting. Serum cortisol levels were significantly higher in patients with schizophrenia than in patients with MDD and controls. Serum cortisol levels were significantly higher in patients with MDD than in controls. Serum IGF-1 levels were higher in both patient groups than in controls, whereas there was no significant difference between patients with MDD and schizophrenia. Both cortisol and IGF-1 levels were positively correlated with the Hamilton Rating Scale for Depression score in patients with MDD, whereas cortisol level was positively correlated and IGF-1 level was negatively correlated with the Brief Psychiatric Rating Scale score in patients with schizophrenia. The differences in the level of these hormones suggest pathophysiological differences between these disorders.

The effect of some family characteristics on the relationship between mental symptoms and levels of serum serotonin and salivatory cortisol

Introduction: Psychological symptoms (PSs) are also seen in healthy individuals. The aim of this study is to examine some familial characteristics in the relationship between PSs and serum serotonin (5-HT) and salivary cortisol (sCTS) levels in healthy individuals. Materials and Method: A sociodemographic data form and a psychiatric symptom screening questionnaire (SCL-90-R) were given to 320 healthy individuals (156 males, 164 females) aged between 18-65 years and without any mental illness. Blood and saliva samples were duly taken and evaluated by ELISA method. The research protocol was approved by the Ankara Keçiören Training and Research Hospital Clinic Research Ethics Committee (study number KÖTRH-CREC_11.07.2012/103). Informed consent was obtained from the participants before participating in the study. Statistical analyzes were performed with the SPSS 15.0 program. Descriptive statistical data (number, percentage, mean, standard deviation, minimum and maximum), independent sample t test, One-way ANOVA test, Kruskal Wallis H test, Mann-Whitney U test, Pearson Correlation analysis were used in the analyzes. For statistical significance, p˂.05 was accepted as significant. Results: The highest PS levels of the participants were obsessive-compulsive symptoms (.92±.80), interpersonal sensitivity (.75±.55) and depressive symptoms (.72±.53), respectively. The general symptom index (GSI) was .61±.46. Psychotic (χ2(2)=7.021, p=.03) and phobic symptoms (χ2(2)=7.130, p=.03) in those living in a nuclear family, depression levels in those whose parents lived together (t=-2.114, p=.04) was lower. Somatization, anxiety, obsession, depression, interpersonal sensitivity, psychoticism, paranoid, thought, hostility and additional symptom levels were highest in illiterate parents. Phobic symptom levels were highest in those whose fathers were illiterate. In patients with a family history of psychiatric illness, somatization (t=2.108, p=.04), anxiety (t=2.103, p=.02), obsession (t=2.146, p=.03), depression (t=2.548, p=.01), anger-hostility (t=3.096, p=

Deficiency of the ywhaz gene, involved in neurodevelopmental disorders, alters brain activity and behaviour in zebrafish

Genetic variants in YWHAZ contribute to psychiatric disorders such as autism spectrum disorder and schizophrenia, and have been related to an impaired neurodevelopment in humans and mice. Here, we have used zebrafish to investigate the mechanisms by which YWHAZ contributes to neurodevelopmental disorders. We observed that ywhaz expression was pan-neuronal during developmental stages and restricted to Purkinje cells in the adult cerebellum, cells that are described to be reduced in number and size in autistic patients. We then performed whole-brain imaging in wild-type and ywhaz CRISPR/Cas9 knockout (KO) larvae and found altered neuronal activity and connectivity in the hindbrain. Adult ywhaz KO fish display decreased levels of monoamines in the hindbrain and freeze when exposed to novel stimuli, a phenotype that can be reversed with drugs that target monoamine neurotransmission. These findings suggest an important role for ywhaz in establishing neuronal connectivity during development and modulating both neurotransmission and behaviour in adults.

Serotonin 5-HT2A receptor polymorphisms are associated with irritability and aggression in conduct disorder

In childhood and adolescence, overt antisocial and aggressive manifestations are typically diagnosed as conduct disorder (CD). Given that the emerging research has pointed to the influence of 5-HT_2A receptors in the ontogeny of aggression, we aimed to analyze the association of its genetic polymorphisms with CD. The study included 228 male adolescent subjects (120 with and 108 without CD). CD was diagnosed according to Structured Clinical Interview for DSM-IV criteria, while evaluations of aggressive/dissociative behaviors were performed using psychometric questionnaires including the PCL-YV, OAS-M, KADS, and CBCL. Platelet 5-HT concentration was determined by spectrophotofluorometry. Genotyping of 5-HT_2A receptor polymorphisms rs2070040, rs9534511, rs4142900, rs9534512 was performed using TaqMan SNP Genotyping Assays. Subjective irritability, physical aggression toward others, and antisocial behavior were strongly associated with the G allele of rs2070040 and rs4142900, and the C allele of rs9534511 and rs9534512. A significantly increased platelet 5-HT concentration in CD subjects, compared to controls, was lost after the correction according to the smoking status. Our results indicate an association of the studied HTR2A polymorphisms and their haplotypes with irritability and impulsivity traits, which may contribute to the aggressive and antisocial behavior in male adolescents with CD.

Cortisol, Prolactin, and Breastmilk Volume; A Promising Pattern for Reducing Postpartum Depression

BACKGROUND: Research shows postnatal depression and shorter breastfeeding are consistently related, but their causal effect remains debatable. To reduce the impact of mental disorders in the perinatal period, lactation may give a significant neuroendocrine effect. AIM: This study aimed to examine hormonal patterns and estimated breastmilk volume of mothers with depression. MATERIALS AND METHODS: This study was conducted during the three-trimester to 6-week postnatal period. It involved 60 pregnant women from South Sulawesi, Indonesia. Analysis of variance with repeated measures was used to compare and review fluctuations and effect sizes of cortisol, prolactin, and breastmilk volume of mothers with depression symptoms. RESULTS: The mean cortisol levels rose in the 4th week and decreased in the 6th week in both groups. There was no substantial difference in the cortisol levels between these periods (p = 0.534; p = 0.553; and p = 0.660), but the prolactin levels continuously increased by 2 weeks and substantially progressed in the 4th and 6th weeks (p < 0.028, p < 0.009), respectively. There was no positive association between cortisol and prolactin levels (p = 0.384). The breastmilk volume was higher every week only in mothers without depression and it slightly decreased in other categories. This study emphasized the prolactin’s protective effect size on a stressful environment characterized by high cortisol; a significant rise in prolactin levels occurred in the 2nd and 4th weeks of postnatal, marking the higher lactation. CONCLUSIONS: Breastfeeding hormones may provide protection against postpartum depression in moms. It is critical to establish a history of prior trauma in nursing mothers in order to facilitate diagnosis and proper care.

Is there a relationship between morphological and functional platelet changes and depressive disorder?

BACKGROUND

Blood platelets, due to shared biochemical and functional properties with presynaptic serotonergic neurons, constituted, over the years, an attractive peripheral biomarker of neuronal activity. Therefore, the literature strongly focused on the investigation of eventual structural and functional platelet abnormalities in neuropsychiatric disorders, particularly in depressive disorder. Given their impact in biological psychiatry, the goal of the present paper was to review and critically analyze studies exploring platelet activity, functionality, and morpho-structure in subjects with depressive disorder.

METHODS

According to the PRISMA guidelines, we performed a systematic review through the PubMed database up to March 2020 with the search terms: (1) platelets in depression [Title/Abstract]"; (2) "(platelets[Title]) AND depressive disorder[Title/Abstract]"; (3) "(Platelet[Title]) AND major depressive disorder[Title]"; (4) (platelets[Title]) AND depressed[Title]"; (5) (platelets[Title]) AND depressive episode[Title]"; (6) (platelets[Title]) AND major depression[Title]"; (7) platelet activation in depression[All fields]"; and (8) platelet reactivity in depression[All fields]."

RESULTS

After a detailed screening analysis and the application of specific selection criteria, we included in our review a total of 106 for qualitative synthesis. The studies were classified into various subparagraphs according to platelet characteristics analyzed: serotonergic system (5-HT2A receptors, SERT activity, and 5-HT content), adrenergic system, MAO activity, biomarkers of activation, responsivity, morphological changes, and other molecular pathways.

CONCLUSIONS

Despite the large amount of the literature examined, nonunivocal and, occasionally, conflicting results emerged. However, the findings on structural and metabolic alterations, modifications in the expression of specific proteins, changes in the aggregability, or in the responsivity to different pro-activating stimuli, may be suggestive of potential platelet dysfunctions in depressed subjects, which would result in a kind of hyperreactive state. This condition could potentially lead to an increased cardiovascular risk. In line with this hypothesis, we speculated that antidepressant treatments would seem to reduce this hyperreactivity while representing a potential tool for reducing cardiovascular risk in depressed patients and, maybe, in other neuropsychiatric conditions. However, the problem of the specificity of platelet biomarkers is still at issue and would deserve to be deepened in future studies.

Relationship Between Gonadal Hormone Levels and Symptom Severity in Female Patients With Schizophrenia

OBJECTIVE

It is thought that sex-specific differences in schizophrenia may be associated with gonadal hormones, especially estrogen. This study aimed to investigate the relationship between follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin, estradiol, and progesterone serum levels and symptom severity during the menstrual cycle in female patients with schizophrenia.

METHODS

Serum samples were taken in the follicular and periovulatory phases from 32 female patients with schizophrenia; and FSH, LH, prolactin, estradiol, and progesterone levels were performed. Simultaneously, the patients were administered positive and negative symptom scale (PANSS), Calgary depression scale for schizophrenia (CDSS), and Hamilton anxiety rating scale (HAM-A).

RESULTS

PANSS (z = -2.52, P < .001), HAM-A (z = -3.60, P < .001), and CDSS (z = -2.52, P = .012) scores were lower in the periovulatory phase than in the follicular phase. Negative correlations between FSH and PANSS positive symptom subscale (r = -0.393, P = .035), and between prolactin and PANSS total score (r = -0.406, P = .029) were detected.

CONCLUSION

Hypoestrogenism should be studied more in patients with schizophrenia. Studies with large samples evaluating FSH, LH, prolactin, and progesterone together with estrogen are needed to be able to safely use gonadal hormones, which may be related to schizophrenia symptom severity, especially in patients who do not respond adequately to treatment.

The association between prolactin concentration and aggression in female patients with schizophrenia

OBJECTIVES

This study assessed the association between serum prolactin (PRL) concentration and aggression in female patients with schizophrenia.

METHODS

Female patients with schizophrenia (N = 120) were diagnosed using SCID-5 based on the DSM-5 criteria. They were sampled at the University Psychiatric Hospital Vrapce during the period from March 2017 to March 2019. Aggression was evaluated using the Positive and Negative Syndrome Scale (PANSS), and Overt Aggression Scale (OAS). Patients were subdivided into aggressive and non-aggressive groups. PRL was determined in serum using electrochemiluminescence (ECLIA) method.

RESULTS

Aggressive patients with schizophrenia had significantly (p < 0.0001) increased PRL concentration compared to non-aggressive patients. Higher PRL concentration was significantly (p < 0.0001) associated with pronounced aggressive symptoms determined by the OAS scores. When patients were subdivided into those who were treated with risperidone, haloperidol, paliperidone, amisulpride, and a group that was not treated with these antipsychotics, aggressive patients in both groups had significantly higher PRL concentrations than non-aggressive patients. Higher antipsychotic dose was related to increased PRL concentration (p = 0.004).

CONCLUSIONS

Our findings suggest that higher PRL is significantly associated with aggression, irrespective of the antipsychotic medication, in female patients with schizophrenia.

Studying the Contribution of Serotonin to Neurodevelopmental Disorders. Can This Fly?

Serotonin is a biogenic amine that acts as neurotransmitter in different brain regions and is involved in complex behaviors, such as aggression or mood regulation. Thus, this amine is found in defined circuits and activates specific receptors in different target regions. Serotonin actions depend on extracellular levels of this amine, which are regulated by its synthetic enzymes and the plasma membrane transporter, SERT. Serotonin acts also as a neurotrophic signal in ontogeny and in the mature brain, controlling cell proliferation, differentiation, neurogenesis, and neural plasticity. Interestingly, early alterations in serotonergic signaling have been linked to a diversity of neurodevelopmental disorders, including autism spectrum disorder (ASD), attention deficit/hyperactivity disorder (ADHD), or mental illnesses like schizophrenia or depression. It has been proposed that given the complex and numerous actions of serotonin, animal models could better serve to study the complexity of serotonin actions, while providing insights on how hindering serotonergic signaling could contribute to brain disorders. In this mini-review, it will be examined what the general properties of serotonin acting as a neurotransmitter in animals are, and furthermore, whether it is possible that Drosophila could be used to study the contribution of this amine to neurodevelopmental and mental disorders.

Elevated Platelet Parameter in First-Episode Schizophrenia Patients: A Cross-Sectional Study

Serotonin (5-HT) and inflammation are 2 major hypotheses in schizophrenia (SZ) pathogenesis, both of which involve platelets. However, the association between platelet and SZ has not been well studied. The aim of this study was to evaluate changes of platelet count (PLT), mean platelet volume (MPV), platelet-large cell ratio (P-LCR), platelet distribution width (PDW), and plateletcrit (PCT) in patients with first-episode schizophrenia (FES). Meanwhile, 3 inflammation markers, including neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and monocyte-lymphocyte ratio (MLR), were evaluated. Complete blood count of 106 FES patients, 82 first-episode depression (FED) patients, and 120 healthy controls (HCs) were compared. In addition, PLR, NLR, and MLR were calculated and compared among 3 groups. Our data suggested that PLT, MPV, P-LCR, PDW, PCT, NLR, PLR, and MLR in FES patients were significantly increased than those in the HCs (P < 0.01 or P < 0.05, respectively). PLT, PCT, PLR, and MLR in FED patients were significantly higher than those in the HCs (P < 0.01). However, no significant difference in MPV, P-LCR, and NLR was identified between FED patients and HCs (P > 0.05). Moreover, MPV, P-LCR, PDW, NLR, and MLR in FES patients were significantly higher than those in FED patients (P < 0.01 or P < 0.05, respectively). The elevation of PLT, MPV, P-LCR, PDW, PCT, NLR, PLR, and MLR in FES patients supported 5-HT and inflammation hypotheses in SZ pathogenesis. Further, our data suggested that increasing levels of MPV, P-LCR, PDW, NLR, and MLR might help to distinguish FES from FED. Clinical Trials.gov ID: 2018JJ2580.

Impact of Acute and Chronic Stress on Thrombosis in Healthy Individuals and Cardiovascular Disease Patients

Psychological stress induces different alterations in the organism in order to maintain homeostasis, including changes in hematopoiesis and hemostasis. In particular, stress-induced hyper activation of the autonomic nervous system and hypothalamic–pituitary–adrenal axis can trigger cellular and molecular alterations in platelets, coagulation factors, endothelial function, redox balance, and sterile inflammatory response. For this reason, mental stress is reported to enhance the risk of cardiovascular disease (CVD). However, contrasting results are often found in the literature considering differences in the response to acute or chronic stress and the health condition of the population analyzed. Since thrombosis is the most common underlying pathology of CVDs, the comprehension of the mechanisms at the basis of the association between stress and this pathology is highly valuable. The aim of this work is to give a comprehensive review of the studies focused on the role of acute and chronic stress in both healthy individuals and CVD patients, focusing on the cellular and molecular mechanisms underlying the relationship between stress and thrombosis.

Stress Enhances Proinflammatory Platelet Activity: the Impact of Acute and Chronic Mental Stress

The role of platelets in hemostasis and thrombosis has long been recognized, recently their contribution to immunological and inflammatory processes is emerging. Platelets could be the missing link between cardiovascular disease, chronic stress and depressive symptoms. Both physical and mental stressors cause platelet activation reflected by changes in platelet bioactivity and aggregation. Here we evaluate the proinflammatory platelet response to acute and chronic mental stress. In a prospective study design an acute mental stress test was administered to 55 healthy male participants once without and once in the presence of chronic mental stress. Blood was collected prior to and at three time points following an acute mental stress test (0, 30, 60 min). Platelet proinflammatory activation markers, were assessed using FACS analysis and aggregability was measured in response to ADP or epinephrine using PFA-100. A linear mixed model was used for analysis. Chronic mental stress lead to a significant increase in state anxiety (p < 0.001), depressive symptoms (p = 0.045) and perceived stress (p = 0.001). The factor “chronic mental stress” was significantly associated with increased numbers of CD63+ platelets (p = 0.009). The factor “acute mental stress” was associated with alterations in CD62P+ platelets (p < 0.001), CD63+ platelets (p = 0.011), PAC-1+ platelets (p < 0.001) as well as platelet leucocyte aggregates (p = 0.019). The recovery of CD62P function following the acute mental stress exposure was significantly impaired by chronic stress (p = 0.023). Aggregation was affected by chronic and acute mental stress. In conclusion, mental stress is linked to an increased and prolonged proinflammatory platelet bioactivity. This proinflammatory and immunomodulatory stimuli could help to explain the link between mental and somatic disorders.

Platelet Serotonin Concentration Is Associated with Illness Duration in Schizophrenia and Chronological Age in Depression

OBJECTIVE

Impaired serotonergic neurotransmission has been implicated in the pathogenesis of depression and schizophrenia. Blood platelets have been used for years as a peripheral model of neuronal serotonin dynamics. The objective was to investigate platelet count and serotonin concentration in patients with depression and schizophrenia, in an attempt to ascertain their clinical usefulness.

METHODS

953 participants were included in the study, 329 patients with depression, 339 patients with schizophrenia and 285 healthy controls. ELISA was used to assess platelet serotonin concentrations.

RESULTS

There were no statistically significant differences among groups regarding age, total platelet count and serotonin concentration. Linear regression analyses revealed inverse correlations between platelet serotonin concentration and age of patients with depression and healthy individuals, as well as between platelet serotonin concentration and illness duration in patients with schizophrenia. In other words, longer illness duration in patients with schizophrenia, and higher age in patients with depression and healthy individuals was associated with lower platelet serotonin concentrations.

CONCLUSION

Platelet count and serotonin concentration did not prove to be of diagnostic value in differentiating patients and healthy individuals. However, illness duration in patients with schizophrenia may be associated with reduced concentrations of platelet serotonin.

Edaravone reduces depression severity in patients with symptomatic intracranial stenosis and is associated with the serum expression of sex hormones

OBJECTIVE

To investigate the effect of edaravone on depression relief in symptomatic patients with intracranial stenosis and its relationship with the expression of sex hormones.

METHODS

We recruited 112 patients with symptomatic intracranial arterial stenosis from Renmin Hospital, Wuhan University, between October 2014 and October 2017. All patients were divided into the traditional or experimental (traditional treatment + intravenous infusion of edaravone 30 mg twice a day for 14 days) treatment groups. The general clinical data were collected, and neurological functional recovery using the Modified Rankin Scale (mRS) and National Institute of Health stroke scale (NIHSS) scores were recorded. Symptom Checklist 90 (SCL-90) was used to assess the general psychological changes of the patient, followed by the 24 Hamilton Depression Scale (HAMD) to examine the incidence of post-stroke depression (PSD). This divided the patients into the mild, moderate, and severe depression groups. Next, we measured the serum protein expression of the sex hormones estradiol (E2), testosterone (T), follicle stimulating hormone (FSH), prolactin (PRL), and luteinizing hormone (LH).

RESULTS

The mRS and NIHSS scores were significantly lower in the experimental group than in the control group (P < .05). There was no significant difference in SCL90 score before intervention (P > .05); the scores were significantly lower in the experimental group after intervention (P < .05). There was a significant difference in SCL-90 and HAMD scores between groups before treatment (P < .05), with significantly lower scores in the experimental group post-treatment (P < .05). The incidence of depression was significantly reduced in the experimental group post-treatment. Furthermore, the expression of E2 and FSH was significantly higher (P < .01) and lower (P < .001), respectively, in women than in men in the experimental group post-treatment. Interestingly, the expression of T was significantly lower in men in the experimental group post-treatment (P < .001).

CONCLUSION

Edaravone significantly improved the clinical efficacy of stent implantation in intracranial artery stenosis treatment by alleviating depression and reducing the incidence of PSD.

Transcriptional changes in the stress pathway are related to symptoms in schizophrenia and to mood in schizoaffective disorder

Altered levels of stress-signalling transcripts have been identified in post-mortem brains of people with schizophrenia, and since stress effects may be expressed throughout the body, there should be similar changes in peripheral cells. However, the extent to which these markers are altered in peripheral white blood cells of people with schizophrenia is not known. Furthermore, how peripheral cortisol and stress-related mRNA are associated with negative symptom severity and emotional states in people with schizophrenia versus schizoaffective disorder has not been determined. Whole blood samples were collected from 86 patients with either schizophrenia or schizoaffective disorder (56 people with schizophrenia and 30 people with schizoaffective disorder), and 77 healthy controls. Total RNA was isolated, cDNA was synthesized, and stress-signalling mRNA levels (for NR3C1, FKBP5, FKBP4, PTGES3 and BAG1) were determined. Stress and symptom severity scores were measured by the Depression, Anxiety and Stress Scale, and the Positive and Negative Syndrome Scale, respectively. We found increased FKBP5 mRNA, Z(156) = 2.5, p = 0.01, decreased FKBP4 mRNA, t(155) = 3.5, p ≤ 0.001, and decreased PTGES3 mRNA, t(153) = 3.0, p ≤ 0.01, in schizophrenia and schizoaffective disorder cohorts combined compared to healthy controls. Stress-related peripheral mRNA levels were differentially correlated with negative emotional states and symptom severity in schizoaffective disorder (β's = -0.45-0.56, p's = 0.05-0.001) and schizophrenia (β's = -0.34-0.38, p's = 0.04-0.03), respectively. Therefore, molecules of the stress-signalling pathway appear to differentially contribute to clinical features of schizophrenia versus schizoaffective disorder.

Involvement of prolactin in newborn infant irritability following maternal perinatal anxiety symptoms

BACKGROUND

Newborn irritability could be an unique and special status and/or adverse neurobehavioral outcomes which was independent of serious disease. To determine whether maternal perinatal anxiety symptoms was associated with newborn irritability, and whether the alteration of serum prolactin in newborns were involved in newborn irritability.

METHODS

205 pregnant women were recruited: normal group (n = 100), and anxiety group (n = 105), which was randomly divided to Newborn Behavioral Observations (NBO)+anxiety group(n = 65) and control+anxiety group(n = 40). Newborn Irritability was assessed by Neonatal Behavioral Assessment Scale(NBAS). Serum prolactin, cortisol and 5-HT in mothers and infants were measured.

RESULTS

1. The scores of irritability items in the newborns of anxiety group were higher than that of the normal group (p < 0.05). 2. Lower serum PRL, 5-HT and higher serum cortisol were found in the newborns of anxiety group compared with that of the control group both postpartum 2d and 15 (p < 0.05). 3. The level of serum PRL in newborn infants were significantly and negatively correlated to the scores of irritability items (p < 0.05). 4. After 7 rounds of NBO interventions, the anxiety scores of mothers and the scores of irritability items of newborns in the NBO intervention group were all lower than those of the control group (p < 0.05) .

LIMITATIONS

In future experiments, we should explore the effect of PRL in the breast milk on newborn infant serum PRL.

CONCLUSIONS

Prolactin could be a potential mediator in newborn irritability following maternal perinatal anxiety symptoms.

Evaluation of peripheral serotonin content and α2-adrenergic receptor function as potential markers for life-long recurrent depressive disorder by using methodological improvements

OBJECTIVE

We aimed to evaluate the role and the relations between peripheral platelet serotonin content, blood plasma serotonin concentration and the function of platelet α₂-adrenergic receptors (α₂-AR) as potential state or trait biomarkers for recurrent depressive disorder (RDD).

METHODS

26 drug-free patients with life-long RDD and 31 healthy controls were included in the study. Several methodological improvements in blood collection and platelet isolation were implemented following the present standards in Haematology and Light transmission aggregometry.

RESULTS

Our results have shown lower platelet serotonin content, higher plasma serotonin concentration and desensitization of platelet α₂-AR in patients with RDD. The variables were found heterogeneous and mainly influenced by the clinical characteristics of the current episode. High amplitude of the α₂-AR correlated with severe anxious symptoms and high platelet serotonin content (as well as low plasma serotonin levels) were associated with psychotic symptoms.

CONCLUSIONS

The evaluated peripheral markers reflect only state (but not trait) abnormalities in patients with current severe episode of RDD. The observed peripheral α₂-AR and serotonin abnormalities are mutually not related and they are probably triggered by different mechanisms.

Review of serum prolactin levels as an antipsychotic-response biomarker

Antipsychotics acting as antagonists at dopamine D2 receptors concentrated in the striatum are the cornerstone of effective treatment of psychosis. Substantial progress in treating persons with schizophrenia could be achieved by the identification of biomarkers which reliably determine the lowest efficacious dose of antipsychotics. Prolactin levels have been considered a promising treatment-response biomarker due to dopamine’s regulation of serum prolactin levels through D2 receptors in the hypothalamic-pituitary pathway. Prolactin secretion in response antipsychotic administration is associated with the antipsychotics affinity for D2 receptors. This review assesses the available literature on the use of serum prolactin levels as an antipsychotic-response biomarker. Articles were identified through PubMed as well as the reference lists of full text articles available online. Relevant publications were summarized briefly to define the limitations and utility of serum prolactin levels as a tool for improving antipsychotic dosing. Serum prolactin levels in combination with prolactin-inducing potencies for each antipsychotic may help identify the lowest effective dose of antipsychotic medications. , In addition to the fact that prolactin secretion is dependent on serum antipsychotic levels and not brain levels, recent findings show that prolactin release is independent of the β-arrestin-2 pathway and GSK3β regulation, one branch of the pathway that has been implicated in antipsychotic efficacy. Therefore, serum prolactin is an indirect biomarker for treatment response. Further investigations are warranted to characterize prolactin-antipsychotic dose-response curves and systematically test the utility of measuring prolactin levels in patients to identify a person’s lowest efficacious dose.

Cortisol in schizophrenia: No association with tobacco smoking, clinical symptoms or antipsychotic medication

Cigarette smoking is associated with higher cortisol levels in healthy subjects. In schizophrenia this relationship is not clear. There are divergent results on the association between cortisol with smoking, clinical symptoms and medication in schizophrenia. This study evaluated this association in 196 Caucasian inpatients with schizophrenia (51.30±26.68years old), subdivided into 123 smokers and 73 non-smokers. Basal salivary cortisol levels were measured twice, at 08.00 and 09.00AM, 90-120min after awakening. The effect of smoking on cortisol was evaluated according to current smoking status, the number of cigarettes/day and the nicotine addiction intensity. The influence of clinical symptoms and/or antipsychotic medication on cortisol was determined using the Positive and Negative Syndrome Scale (PANSS), and chlorpromazine equivalent doses. Non-smokers were older, received lower doses of antipsychotics, had higher PANSS scores, and had longer duration of illness than smokers. Salivary cortisol was similar in schizophrenic patients subdivided according to the smoking status, the number of cigarettes/day and nicotine addiction intensity. No significant correlation was found between salivary cortisol and PANSS scores, chlorpromazine equivalent doses, age of onset or the duration of illness. The findings revealed no association between salivary cortisol and smoking, nicotine addiction intensity, or clinical symptoms. Our preliminary data showed no correlation between salivary cortisol and chlorpromazine equivalent doses and/or antipsychotic medication. Our findings suggest that smoking does not affect the cortisol response in schizophrenic patients as it has been shown in healthy individuals. Future studies should investigate a possible desensitization of the stress system to smoking.

Theranostic Biomarkers for Schizophrenia

Schizophrenia is a highly heritable, chronic, severe, disabling neurodevelopmental brain disorder with a heterogeneous genetic and neurobiological background, which is still poorly understood. To allow better diagnostic procedures and therapeutic strategies in schizophrenia patients, use of easy accessible biomarkers is suggested. The most frequently used biomarkers in schizophrenia are those associated with the neuroimmune and neuroendocrine system, metabolism, different neurotransmitter systems and neurotrophic factors. However, there are still no validated and reliable biomarkers in clinical use for schizophrenia. This review will address potential biomarkers in schizophrenia. It will discuss biomarkers in schizophrenia and propose the use of specific blood-based panels that will include a set of markers associated with immune processes, metabolic disorders, and neuroendocrine/neurotrophin/neurotransmitter alterations. The combination of different markers, or complex multi-marker panels, might help in the discrimination of patients with different underlying pathologies and in the better classification of the more homogenous groups. Therefore, the development of the diagnostic, prognostic and theranostic biomarkers is an urgent and an unmet need in psychiatry, with the aim of improving diagnosis, therapy monitoring, prediction of treatment outcome and focus on the personal medicine approach in order to improve the quality of life in patients with schizophrenia and decrease health costs worldwide.

Platelet serotonin concentration and depressive symptoms in patients with schizophrenia

Depressive symptoms seem to be frequent in schizophrenia, but so far they have received less attention than other symptom domains. Impaired serotonergic neurotransmission has been implicated in the pathogenesis of depression and schizophrenia. The objectives of this study were to investigate platelet serotonin concentrations in schizophrenic patients with and without depressive symptoms, and to investigate the association between platelet serotonin concentrations and symptoms of schizophrenia, mostly depressive symptoms. A total of 364 patients were included in the study, 237 of which had significant depressive symptoms. Significant depressive symptoms were defined by the cut-off score of 7 or more on Calgary Depression Rating Scale (CDSS). Platelet serotonin concentrations were assessed by the enzyme-linked immunosorbent assay (ELISA). Prevalence of depression in patients with schizophrenia was 65.1%. Schizophrenic patients with depressive symptoms showed lower platelet serotonin concentrations (mean±SD; 490.6±401.2) compared to schizophrenic patients without depressive symptoms (mean±SD; 660.9±471.5). An inverse correlation was established between platelet serotonin concentration and depressive symptoms, with more severe symptoms being associated with lower platelet serotonin concentrations. Depressive symptoms in schizophrenic patients may be associated with reduced concentrations of platelet serotonin.

The association between autism and schizophrenia spectrum disorders: A review of eight alternate models of co-occurrence

Although now believed to be two distinct disorders, autism spectrum disorders (ASD) and schizophrenia spectrum disorders (SSD) share multiple phenotypic similarities and risk factors, and have been reported to co-occur at elevated rates. In this narrative review, we give a brief overview of the phenomenological, genetic, environmental, and imaging evidence for the overlap between ASD and SSD, highlighting similarities and areas of distinction. We examine eight possible alternate models of explanation for the association and comorbidity between the disorders, and set out a research agenda to test these models. Understanding how and why these disorders co-occur has important implications for diagnosis, treatment, and prognosis, as well as for developing fundamental aetiological models of the disorders.

Plasma and platelet clusterin ratio is altered in Alzheimer's disease patients with distinct neuropsychiatric symptoms: findings from a pilot study

BACKGROUND

Clusterin protein in plasma has been found to differentiate between people with and without cognitive changes. However, these findings are not conclusive, despite the clusterin gene variations repeatedly being linked to increased risk for dementia, in particular Alzheimer's disease (AD).

METHOD

We analysed the level of clusterin in platelet and plasma in 25 subjects with a clinical diagnosis of AD and 26 subjects with no cognitive impairment.

RESULTS

In the current study, we report that the levels of both plasma and platelet clusterin are similar between AD and cognitively intact individuals. Clusterin plasma and platelet levels, as well as the plasma/platelet clusterin ratio, were not affected by age, gender, cognitive impairment and/or overt behavioural symptomatology, including presence of hallucinations and delusions, as well as depression. However, the plasma/platelet clusterin ratio was positively associated in with the Neuropsychiatric Inventory measures of agitation, apathy, irritability and motor aberrant behaviour in AD subjects.

CONCLUSION

Previous inconsistencies in reported blood clusterin levels may be a result of underlying non-cognitive symptoms in people with AD. Our findings need now to be replicated in larger group of dementia subjects.

Cortisol, platelet serotonin content, and platelet activity in patients with major depression and type 2 diabetes: an exploratory investigation

OBJECTIVE

Hypothalamic-pituitary-adrenal system dysfunction, serotonergic system alterations, and enhanced platelet activity may contribute to the increased cardiac risk in depression. This exploratory study examined associations between cortisol parameters, platelet serotonin (5-HT) content, and platelet activity markers in patients with newly diagnosed major depression (MD) and/or Type 2 diabetes (T2DM) compared with healthy controls.

METHODS

We compared cortisol awakening response (CAR), diurnal decrease in salivary cortisol concentrations (slope), platelet 5-HT, and platelet markers (CD40, CD40 ligand [CD40L], soluble CD40L, CD62P, β-thromboglobulin, and platelet factor-4) in 22 T2DM patients, 20 MD patients, 18 T2DM patients with MD, and 24 healthy controls.

RESULTS

Platelet markers were elevated in MD (F(6,60) = 11.14, p < .001) and T2DM (F(6,60) = 13.07, p < .001). Subgroups did not differ in 5-HT or cortisol slope, whereas T2DM patients without depression had significantly lower CAR than did healthy controls (F(1,61) = 7.46, p = .008). In healthy controls, cortisol slope correlated with platelet activity for CD40 (r = -0.43, p = .048) and 5-HT was correlated with CD40L (r = 0.53, p = .007). In patients with both T2DM and MD, 5-HT and CD62P were correlated (r = 0.52, p = .033).

CONCLUSIONS

Increased platelet activity in T2DM and MD may play a role in the association between diabetes, depression, and coronary artery disease. The present data suggest that group differences in cortisol or 5-HT as well as group-specific associations of cortisol or 5-HT with platelet markers might be of limited importance in the shared pathways of T2DM and depression in the pathophysiology of coronary artery disease.

System responses to chronic cold stress probed via1H NMR spectroscopy in plasma and urine matrices

The metabolic pathways in plasma and urine revealed the biochemical changes under chronic cold stress from a systematic and holistic view.

Morning cortisol levels in schizophrenia and bipolar disorder: a meta-analysis

Increased peripheral levels of morning cortisol have been reported in people with schizophrenia (SZ) and bipolar disorder (BD), but findings are inconsistent and few studies have conducted direct comparisons of these disorders. We undertook a meta-analysis of studies examining single measures of morning cortisol (before 10 a.m.) levels in SZ or BD, compared to controls, and to each other; we also sought to examine likely moderators of any observed effects by clinical and demographic variables. Included studies were obtained via systematic searches conducted using Medline, BIOSIS Previews and Embase databases, as well as hand searching. The decision to include or exclude studies, data extraction and quality assessment was completed in duplicate by LG, SM and AS. The initial search revealed 1459 records. Subsequently, 914 were excluded on reading the abstract because they did not meet one or more of the inclusion criteria; of the remaining 545 studies screened in full, included studies were 44 comparing SZ with controls, 19 comparing BD with controls, and 7 studies directly comparing schizophrenia with bipolar disorder. Meta-analysis of SZ (N=2613, g=0.387, p=0.001) and BD (N=704, g=0.269, p=0.004) revealed moderate quality evidence of increased morning cortisol levels in each group compared to controls, but no difference between the two disorders (N=392, g=0.038, p=0.738). Subgroup analyses revealed greater effect sizes for schizophrenia samples with an established diagnosis (as opposed to 'first-episode'), those that were free of medication, and those sampled in an inpatient setting (perhaps reflecting an acute illness phase). In BD, greater morning cortisol levels were found in outpatient and non-manic participants (as opposed to those in a manic state), relative to controls. Neither age nor sex affected cortisol levels in any group. However, earlier greater increases in SZ morning cortisol were evident in samples taken before 8 a.m. (relative to those taken after 8 a.m.). Multiple meta-regression showed that medication status was significantly associated with morning cortisol levels in SZ, when the effects of assay method, sampling time and illness stage were held constant. Heightened levels of morning cortisol in SZ and BD suggest long-term pathology of the hypothalamic-pituitary-adrenal (HPA) axis that may reflect a shared process of illness development in line with current stress-vulnerability models.

Avaliação do funcionamento do eixo HPA em deprimidos por meio de medidas basais: revisão sistemática da literatura e análise das metodologias utilizadas

Objetivo Realizar revisão sistemática da literatura para conhecer a atividade do eixo hipotálamo-pituitária-adrenal (HPA) em deprimidos considerando-se as medidas basais dos hormônios e analisar criticamente as metodologias utilizadas. Métodos Foi realizada busca de artigos nas bases de dados PubMed e SciELO. Na primeira base de dados, introduziram-se as palavras-chave “depressive disorder” e “HPA axis”, e na segunda utilizaram-se os termos “depression” ou “depressão” e “HHA” ou “HPA axis”. Optou-se por pesquisa realizada em humanos adultos, em inglês e português, do ano 2000 até 2011. Resultados Dos 27 artigos selecionados, obtiveram-se como resposta do eixo HPA tanto hiperatividade como atividade desregulada, hipoatividade ou não alteração. Tais resultados dependem das variáveis e dos hormônios estudados, do fluido coletado – plasma, urina, saliva, líquido cefalorraquidiano – do horário de coleta, do número de coletas, da análise estatística utilizada, do subtipo de doença depressiva, entre outros. Conclusão: Os resultados não apresentam consenso em relação à atividade do eixo HPA. Considerando as variáveis estudadas, o eixo HPA, na maioria das vezes, apresenta-se disfuncional na presença da depressão.

Stress, schizophrenia and bipolar disorder

The role of stress in precipitating psychotic episodes in schizophrenia and bipolar disorder has long been acknowledged. However, the neurobiological mechanism/s of this association have remained elusive. Current neurodevelopmental models of psychosis implicate early dysfunction in biological systems regulating hypothalamic-pituitary-adrenal axis and immune function, with long-term effects on the development of the brain networks responsible for higher order cognitive processes and stress reactivity in later life. There is also increasing evidence of childhood trauma in psychosis, and its impact on the development of brain systems regulating stress. These findings are emerging in the context of a new era of epigenetic methods facilitating the study of environmental effects on gene expression. The evidence is thus converging: exposure to stress at critical periods in life may be an important factor in the development of the brain dysfunction that represents psychosis vulnerability, rather than merely interacting with an independent 'biological vulnerability' to manifest in psychosis.

Prolactin and psychopathology in schizophrenia: a literature review and reappraisal

Secretion of the anterior pituitary hormone prolactin can be significantly increased by antipsychotic drugs, leading to a range of adverse effects in patients with schizophrenia. However, there is evidence from a variety of studies that prolactin may also be related to symptom profile and treatment response in these patients, and recent work has identified variations in prolactin secretion even in drug-free patients. In this paper, a selective review of all relevant studies pertaining to prolactin and schizophrenia, including challenge and provocation studies, is presented. The implications of this work are discussed critically. A tentative model, which synthesizes these findings and argues for a significant role for prolactin in the development of schizophrenia, is outlined.

Allostatic load as a tool for monitoring physiological dysregulations and comorbidities in patients with severe mental illnesses

Severe mental illnesses like schizophrenia and bipolar disorder are disabling, chronic conditions that are often accompanied by medical comorbidities. In this theoretical article, we review the allostatic load model representing the "wear and tear" that chronic stress exacts on the brain and body. We propose an innovative way of monitoring physical and psychiatric comorbidities by integrating the allostatic load model into clinical practice. By interpreting peripheral biomarkers differently, medical professionals can calculate a simple, count-based, allostatic load index known to predict diverse stress-related pathologies. In addition to screening for comorbidities, allostatic load indices can be used to monitor the effects of pharmacological and psychosocial interventions. This framework can also be used to generate a dialogue between patient and practitioner to promote preventive and proactive approaches to health care.

Changes in the maternal hypothalamic-pituitary-adrenal axis in pregnancy and postpartum: influences on maternal and fetal outcomes

Overexposure of the developing fetus to glucocorticoids is hypothesised to be one of the key mechanisms linking early life development with later life disease. The maternal hypothalamic-pituitary-adrenal (HPA) axis undergoes dramatic changes during pregnancy and postpartum. Although cortisol levels rise threefold by the third trimester, the fetus is partially protected from high cortisol by activity of the enzyme 11β-hydroxysteroid dehydrogenase type 2 (HSD11B2). Maternal HPA axis activity and activity of HSD11B2 may be modified by maternal stress and disease allowing greater transfer of glucocorticoids from mother to fetus. Here we review emerging data from human studies linking dysregulation of the maternal HPA axis to outcomes in both the mother and her offspring. For the offspring, greater glucocorticoid exposure is associated with lower birth weight and shorter gestation at delivery. In addition, evidence supports longer term consequences for the offspring including re-setting of the HPA axis and susceptibility to neurodevelopmental problems and cardiometabolic disease. For the mother, the changes in the HPA axis, particularly in the postpartum period, may increase vulnerability to mood disturbances. Further understanding of the changes in the HPA axis during pregnancy and the impact of these changes may ultimately allow early identification of those most at risk of future disease.

Redox dysregulation in the pathophysiology of schizophrenia and bipolar disorder: insights from animal models

SIGNIFICANCE

Schizophrenia (SZ) and bipolar disorder (BD) are classified as two distinct diseases. However, accumulating evidence shows that both disorders share genetic, pathological, and epidemiological characteristics. Based on genetic and functional findings, redox dysregulation due to an imbalance between pro-oxidants and antioxidant defense mechanisms has been proposed as a risk factor contributing to their pathophysiology.

RECENT ADVANCES

Altered antioxidant systems and signs of increased oxidative stress are observed in peripheral tissues and brains of SZ and BD patients, including abnormal prefrontal levels of glutathione (GSH), the major cellular redox regulator and antioxidant. Here we review experimental data from rodent models demonstrating that permanent as well as transient GSH deficit results in behavioral, morphological, electrophysiological, and neurochemical alterations analogous to pathologies observed in patients. Mice with GSH deficit display increased stress reactivity, altered social behavior, impaired prepulse inhibition, and exaggerated locomotor responses to psychostimulant injection. These behavioral changes are accompanied by N-methyl-D-aspartate receptor hypofunction, elevated glutamate levels, impairment of parvalbumin GABA interneurons, abnormal neuronal synchronization, altered dopamine neurotransmission, and deficient myelination.

CRITICAL ISSUES

Treatment with the GSH precursor and antioxidant N-acetylcysteine normalizes some of those deficits in mice, but also improves SZ and BD symptoms when given as adjunct to antipsychotic medication.

FUTURE DIRECTIONS

These data demonstrate the usefulness of GSH-deficient rodent models to identify the mechanisms by which a redox imbalance could contribute to the development of SZ and BD pathophysiologies, and to develop novel therapeutic approaches based on antioxidant and redox regulator compounds.

Platelets and depression in cardiovascular disease: A brief review of the current literature

Major depression is an independent risk factor for cardiovascular mortality and morbidity. The exact mechanisms linking depression and increased cardiovascular risk remain poorly understood. Several mechanisms have been proposed including increased platelet reactivity. This review focuses on the current literature that examines the platelet hypothesis of depression. To date studies show increased serotonin response, increased platelet serotonin receptor density, decreased serotonin transporter binding, and decreased platelet serotonin levels in individuals with depression. However other studies have shown no change in serotonin uptake. In addition to platelet serotonin specific pathways, other platelet pathways that have shown significant changes in depressed individuals include blunting of the platelet adenosine response, increased platelet thrombin response, increased glycoprotein Ib expression, increased P-selectin, β thromboglobulin, and platelet factor four, as well as decreased platelet brain derived neurotrophic factor. However there are other studies that show conflicting evidence of increased platelet activation as measured by integrin receptor α_2bβ₃. Other conflicting data include α adrenergic density and platelet response to augmented serotonin. The direction of future research in platelet functional changes in depression and coronary artery disease should continue to focus on serotonin specific pathways with emphasis on potential mechanisms of specific pathway changes.

Platelets: A possible glance into brain biological processes in schizophrenia

Schizophrenia is a severe mental disorder, characterized by behavioral, emotional and cognitive disturbances, which commonly follows a chronic course. Diagnostic accuracy, management plans, treatment evaluation and prognosis are dependent on relatively subjective assessments. Despite extensive research and improvement in imaging technology, as well as modern genetic and molecular methodologies, the biological basis of this disease is still unclear. Therefore, there is a need for objective and valid biological markers. Platelets have often been used as a model in neurobiological research. The accessibility of platelets and their similarities with neurons turns them into an attractive candidate to search for biological markers for diagnosis and for unraveling pathophysiological processes relevant to the etiology of brain disorders, including schizophrenia. The present review addresses the main changes in platelet physiology observed in schizophrenia and its response to antipsychotic medication. We summarize numerous studies demonstrating impaired metabolism, uptake and receptor kinetics of schizophrenia-relevant neurotransmitters, abnormalities in membrane derived phospholipids and polyunsaturated fatty acids, as well as dysfunctions in the mitochondria. These changes fit with the various hypotheses raised for the etiology of schizophrenia, including the dopamine-glutamate hypothesis, the autoimmune hypothesis, the polyunsaturated fatty acid hypothesis and the impaired energy metabolism hypothesis. Despite extensive research in platelets, no conclusive reliable biomarker has been identified yet. This review suggests that the clinical heterogeneity and the biological complexity of schizophrenia lead to the inevitable conclusion that biomarkers will be identified only for subgroups characterized according to the different diagnostic criteria. Moreover, any biomarker would have to be an array of interrelated factors or even a set of several such arrays.

Life stressors and 5-HTTLPR interaction in relation to midpregnancy depressive symptoms among African-American women

OBJECTIVE

In earlier analyses of nonHispanic White women we found a stronger relation between abuse history and midpregnancy elevated depressive symptoms in women with the serotonin transporter (5-HTTLPR) S/S genotype. Here, we focus on African-American women (N=698). Our inquiry is motivated by racial differences in depression diagnosis/treatment, stressors, and frequency of major 5-HTTLPR alleles (S, LA, LG).

MATERIALS AND METHODS

Stressful life events (lifetime) and depressive symptoms (current) were ascertained at 15-27 weeks gestation. A Center for Epidemiological Studies Depression Score of more than or equal to 18 was considered 'elevated'. Life events were scored together and separated into six subconstructs. 5-HTTLPR genotypes were grouped as follows: (i) L and S alleles, (ii) S-LG equivalence ('triallelic to biallelic'), and (iii) LA/LA, all others, S/S ('high/intermediate/low'). Odds ratios (OR) for 'elevated' depressive symptoms-life events (total and subconstructs) relations were calculated for each genotype grouping.

RESULTS

The prevalence of 'elevated' depressive symptoms did not vary by genotype. The relation between stressful life events and 'elevated' depressive symptoms was stronger in S/S compared with LA/LA genotype (interaction P=0.11). Of the six subconstructs, only abuse showed a statistically significant gene-environment interaction. The OR for the abuse-'elevated' depressive symptoms association was greater for S/S vs. LA/LA genotype (interaction P=0.03) and in the 'triallelic to biallelic' grouping (interaction P=0.04). In the 'high/intermediate/low' grouping, 'low' (S/S) had a higher OR (5.5) than both 'intermediate' and 'high' (ORs≤2.3) (interaction P=0.10).

CONCLUSIONS

These results show the importance of examining racial groups, specific stressful events, and different 5-HTTLPR genotype groupings when exploring gene-environment interactions in depression.

Daily cortisol, stress reactivity and psychotic experiences in individuals at above average genetic risk for psychosis

BACKGROUND

Hypothalamic-pituitary-adrenocortical (HPA) axis abnormalities have been found in patients with a psychotic disorder and first-degree relatives of patients with a psychotic disorder react with subtle increases in non-clinical psychotic experiences and negative emotions in the face of everyday stress. The current study investigated whether HPA axis functioning is altered in individuals at above average genetic risk for psychotic disorder, examining diurnal cortisol profiles, cortisol reactivity to daily stressors and the association between HPA axis activity and subclinical psychotic experiences.

METHOD

Participants included siblings of patients with a psychotic disorder (n=60) and a healthy comparison group (n=63). The Experience Sampling Method (a structured diary technique) was employed to assess stress, psychotic experiences, negative affect and salivary cortisol repeatedly in the flow of daily life.

RESULTS

Multi-level analyses revealed higher diurnal cortisol levels and heightened cortisol reactivity to negative daily events in siblings compared with controls. Diurnal cortisol slope did not differ between the two groups, but momentary increases in psychotic experiences and negative affect were associated with increased cortisol in the sibling group.

CONCLUSIONS

Findings support altered HPA axis activity in individuals at above average genetic risk for psychotic disorder, as evidenced by higher diurnal cortisol levels and increased cortisol reactivity to daily stress. Results also suggest a dynamic association between cortisol secretion and the intensity of psychotic-like experiences and negative emotions in daily life, although the direction of this association remains to be elucidated.

Abnormal plasma monoamine metabolism in schizophrenia and its correlation with clinical responses to risperidone treatment

Abnormalities in plasma monoamine metabolism reflect partly the illness of schizophrenia and sometimes the symptoms. Such studies have been repeatedly reported but have rarely taken both metabolites and parent amines or inter-amine activity ratios into account. In this study, the monoamines, their metabolites, turnovers and between-metabolite ratios in plasma were measured longitudinally in 32 schizophrenic patients treated with risperidone for 6 weeks, to examine possible biochemical alterations in schizophrenia, and to examine the association between treatment responses and psychopathology assessed according to the Positive and Negative Syndrome Scale (PANSS). The results showed lower level of plasma 3,4-dihydroxyphenylacetic acid (DOPAC) in relapsed versus first-episode schizophrenic patients, higher norepinephrine (NE) turnover rate (TR) in undifferentiated in comparison to paranoid schizophrenic patients and relatively higher metabolic activity of dopamine (DA) to serotonin (5-HT) in first-episode versus relapsed schizophrenic patients. Risperidone treatment induced a decrement of plasma DA levels and increments of plasma DOPAC and DA TR in the total group of schizophrenic patients. The turnover rate of 5-HT was was reduced in undifferentiated and relapsed subgroups of schizophrenic patients. The linkages between 5-HT TR, DA/NE relative activity and clinical symptomatology were also identified. These findings are consistent with an involvement of these systems in the pathogenesis of schizophrenia as well as in the responses to treatment, and the usefulness of certain biochemical indices as markers for subgrouping.

A transdisciplinary perspective of chronic stress in relation to psychopathology throughout life span development

The allostatic load (AL) model represents an interdisciplinary approach to comprehensively conceptualize and quantify chronic stress in relation to pathologies throughout the life cycle. This article first reviews the AL model, followed by interactions among early adversity, genetics, environmental toxins, as well as distinctions among sex, gender, and sex hormones as integral antecedents of AL. We next explore perspectives on severe mental illness, dementia, and caregiving as unique human models of AL that merit future investigations in the field of developmental psychopathology. A complimenting transdisciplinary perspective is applied throughout, whereby we argue that the AL model goes beyond traditional stress–disease theories toward the advancement of person-centered research and practice that promote not only physical health but also mental health.

Thrombocyte serotonin and serum cholesterol concentration in suicidal and non-suicidal depressed patients

INTRODUCTION

Numerous studies have confirmed the connection of reduced serum cholesterol and thrombocyte serotonin concentration with suicidal behavior in psychiatric patients. The purpose of such studies was to determine the link among cholesterol and serotonin concentration, comparing depressed patients with and without attempted suicide with phenotypically healthy control group.

MATERIALS AND METHODS

The examinees' groups consisted of 55 depressed patients with suicide attempt and 77 depressed patients with no suicide attempt. In accordance to ICD-10, the above patients were separated in two subgroups; F32.2 and F33.2. Phenotypically healthy control group was presented by the group of healthy blood donors. The fasting serum cholesterol concentration was established using standard enzymatic method, while the thrombocyte serotonin concentration was determined by the enzymatic immune-chemical method (ELISA).

RESULTS

The ANOVA test (N=228, F(ratio)=8.26, p<0.001) found significant difference of cholesterol concentration between groups, with lowest concentration in depressed patients with attempted suicide (SNK post hoc test, p<0.05). Upon gender stratification, the significance remained for the female patients (ANOVA, N=125, F(ratio)=6.06, p=0.003). The serum cholesterol was shown to be statistically lower in the group of depressed patients with attempted suicide, diagnoses F32.2 (p=0.031) and F33.2 (p=0.011), compared to the group of depressed patients without attempted suicides. The thrombocyte serotonin was found to be significantly different in all examined groups, with the lowest thrombocyte serotonin in the group of depressed patients with no suicide attempt (SNK post hoc test, p<0.05, N=187, F(ratio)=37.69, p<0.001). The same significance was found for the group of female (ANOVA, N=103, F(ratio)=11.81, p<0.001) and the group of male patients (ANOVA, N=84, F(ratio)=30.40, p<0.001). The thrombocyte serotonin was significantly lower in the group of depressed patients with no suicide attempt (F32.2), compared to the same diagnosis in the group of depressed patients with suicide attempt (MW-test, p=0.018).

CONCLUSION

In the group of depressed patients with attempted suicide, statistically significant lower serum cholesterol values have been confirmed. In the group of depressed patients with no suicide attempt, statistically significant lower values of thrombocyte serotonin have been confirmed, presumably as the response to the psychopharmacological therapy.

Suicide attempt, smoking, comorbid depression, and platelet serotonin in alcohol dependence

The risk of suicide in patients with alcoholism increases if alcoholism is related to comorbid depression. Both alcoholism and suicidal behavior are associated with reduced serotonin (5-hydroxytryptamine [5-HT]) function. Because suicide is enormous public health problem worldwide, to prevent suicide attempts, it is important to find peripheral marker of suicidal behavior. The aim of this study was to assess whether platelet 5-HT concentration is altered in alcoholic patients with or without suicide attempt. Platelet 5-HT concentration was evaluated in 397 male and 108 female ethnically homogenous medication-free patients with alcoholism, subdivided according to smoking status, comorbid depression, and a history of suicide attempt and in 450 male and 139 female healthy control (nonsuicidal) subjects. Suicide attempt was assessed by two measures: according to the score 4 on the item 3 from the Hamilton Rating Scale for Depression and according to the Structured Clinical Interview regarding suicidal attempt during lifetime. Both male and female patients with alcoholism who were nonsmokers had significantly lower platelet 5-HT concentration than the corresponding healthy subjects. Multifactor analyses of variance revealed the significant effects of alcoholism and smoking, but the lack of significant effects of suicide attempt, sex, or comorbid depression, and no interactions between variables, on platelet 5-HT concentration. Platelet 5-HT concentration did not differ significantly between suicidal patients compared with nonsuicidal patients with alcoholism. Because the results from the present study showed similar platelet 5-HT values between patients with or without a history of suicide attempt, our data did not support the hypothesis that platelet 5-HT concentration might be used as a peripheral marker of the pronounced suicidal behavior in alcoholism.

Cortisol rapidly disrupts prepulse inhibition in healthy men

Stress is known to affect sensorimotor gating (measured with prepulse inhibition of startle, or PPI), possibly improving perception of threat signals at the expense of other input during states of arousal. Stress also induces a variety of autonomic nervous system and endocrine responses, such as an activation of the hypothalamic-pituitary-adrenal axis. The latter will result in the release of the stress hormone cortisol which is known to exert rapid and sustained action on several CNS processes. Since previous studies have not clarified whether and which stress response components may mediate effects on sensorimotor gating, this study asked whether a link may exist between cortisol and sensorimotor gating. We tested whether cortisol may affect PPI by assessing PPI before, during, and after non-stressful, covert 1mg IV cortisol infusions in 27 healthy men in a single-blind and placebo-controlled within-subject design. Cortisol induced a rapid reduction of PPI, with its maximum at 20 min after administration, and PPI returned to baseline after another 20 min. Startle magnitude in the absence of a prepulse was not affected. This rapid effect of the IV cortisol infusions is probably mediated by a non-genomic mechanism. We conclude that stress effects on sensorimotor gating may be mediated by glucocorticoids. The disruption of sensorimotor gating by the stress hormone cortisol may serve the processing of intense and potentially dangerous startling stimuli.

A randomised controlled study of risperidone and olanzapine for schizophrenic patients with neuroleptic-induced acute dystonia or parkinsonism

The objective of this study was to compare the effects of risperidone and olanzapine in schizophrenic patients with intolerant extrapyramidal side effects (EPS) on first generation antipsychotics. We conducted an 8-week, rater-blinded, flexible dose study. Seventy patients with schizophrenia, who met the DSM-IV research criteria of having neuroleptic-induced acute dystonia or parkinsonism, were randomly assigned to risperidone or olanzapine group. The primary outcome was a comparison of the incidence of concomitant anticholinergic drugs usage between the groups to manage their acute dystonia and parkinsonism. The average doses of risperidone and olanzapine from baseline to study end point were 1.8-3.5 mg/day and 7.7-11.7 mg/day, respectively. There were no significant differences in demographic data, severity of EPS or psychotic symptoms between the groups at baseline assessment. Patients taking risperidone had significantly higher incidence of using anticholinergic drugs to manage acute dystonia or parkinsonism overall during the study (OR = 5.17, 95%CI = 1.49-17.88, P = 0.013). There was no significant between-group difference in the changing of rating scales of EPS and psychotic symptoms. The results of our study favour olanzapine as a better choice in schizophrenic patients with intolerant EPS. Double-blinded, fixed dose and different ethnical study for EPS-intolerant schizophrenic patients is needed to confirm the results of our study.

A systematic review of hypothalamic-pituitary-adrenal axis function in schizophrenia: implications for mortality

There is convincing evidence that environmental stress plays a significant role in modifying both mental and physical health. The biological mechanisms linking stress to ill health are not fully understood, but significant evidence points to a central role of the stress axes; the hypothalamic- pituitary-adrenal (HPA) axis and the sympathetic nervous system. Together these two systems link the brain and the body and are crucial in maintaining homeostasis as well as improving an organism's survival chances in the face of environmental challenge. There is evidence of altered HPA axis function in people with a range of mental disorders, and this may in part explain the poor physical health of people with psychotic, mood and anxiety disorders. This paper systematically reviews HPA axis function in people with schizophrenia and relates this to the pattern of physical health seen in this disease. In summary, the evidence suggests people with schizophrenia can experience both hyper- and hypo-function of the HPA axis. It is likely that this contributes to the pattern of poor physical health and premature mortality suffered by people with schizophrenia, in particular the high rates of cardiovascular and metabolic disturbance.