Coagulation activation and fibrinolysis impairment are reduced in patients with anxiety and depression when medicated with serotonergic antidepressants

Impact of Drugs Used in Intensive Care on Routine Coagulation Testing

Coagulation testing is commonly used in the intensive care unit (ICU) to monitor and manage the hemostatic balance, assess bleeding risk, and guide anticoagulant therapy. Routine tests used for this purpose include prothrombin time, activated partial thromboplastin time, fibrinogen, and anti-Xa assays. Some of the drugs commonly used in critically ill patients may influence coagulation assays by interacting in vitro with reagents or in vivo with coagulation pathways, thus altering the coagulation cascade and the fibrinolytic pathway. While the pharmacological effects of drugs on coagulation are usually documented, to our knowledge, no comprehensive review article has been published to date. In this review, we have conducted a critical analysis of the literature to define: (1) the impact of hydroxocobalamin, intravenous lipid emulsion, and propofol on chromogenic assays; (2) the impact of PEGylated compounds, emicizumab, recombinant activated factor VII, antibiotics, and sugammadex on chronometric assays; (3) the challenges associated with bridging anticoagulation in the ICU as well as the effect of N-acetylcystein, serotonin reuptake inhibitors, and tramadol on the hemostasis system. For each drug, we specify the routine coagulation assay that is impacted, whether this is linked to an in vitro interference or an in vivo effect, and the potential consequences on patient management.

Pathophysiological Links Between Myocardial Infarction and Anxiety Disorder, Major Depressive Disorder, Bipolar Disorder and Schizophrenia

There is increasing evidence demonstrating that psychiatric conditions elevate the risk of developing accelerated atherosclerosis and early-onset cardiovascular disease (CVD), including myocardial infarction (MI). Several mechanisms contribute to this observation. The dysfunction of the autonomic nervous system and hyperactivity of the hypothalamic-pituitary-adrenal axis in these patients contribute to the development of MI. Additionally, patients with underlying psychiatric disorders often have abnormal levels of anti-inflammatory and pro-inflammatory cytokines, which can lead to early vascular damage and subsequent atherosclerosis. Elevated PAI-1 levels, reduced tPA activity, and the decreased brain-derived neurotrophic factor (BDNF), influenced by coagulation and inflammation, may contribute to depression and its link to MI. Oxidative stress, marked by increased reactive species and impaired antioxidant defenses, is associated with cellular damage and has been consistently implicated in schizophrenia and bipolar disorder, potentially contributing to myocardial infarction. Finally, molecular genetic studies have indicated that psychiatric disorders and myocardial infarction may share potential pleiotropic genes. The interplay between the psychiatric conditions and myocardial infarction underscores the importance of integrated care approaches to manage both mental and physical health.

The relevance of endoplasmic reticulum lumen and Anoctamin-8 for major depression: Results from a systems biology study

Major depressive disorder (MDD) is a highly prevalent and debilitating disorder, yet its pathophysiology has not been fully elucidated. The aim of this study is to identify novel potential proteins and biological processes associated with MDD through a systems biology approach. Original articles involving the measurement of proteins in the blood of patients diagnosed with MDD were selected. Data on the differentially expressed proteins (DEPs) in each article were extracted and imported into R, and the pathfindR package was used to identify the main gene ontology terms involved. Data from the STRING database were combined with the DEPs identified in the original studies to create expanded networks of protein-protein interactions (PPIs). An R script was developed to obtain the five most reliable connections from each DEP and to create the networks, which were visualized through Cytoscape software. Out of 510 articles found, eight that contained all the values necessary for the analysis were selected, including 1112 adult patients with MDD and 864 controls. A total of 240 DEPs were identified, with the most significant gene ontology term being "endoplasmic reticulum lumen" (46 DEPs, p-value = 5.5x10-13). An extended PPI network was obtained, where Anoctamin-8 was the most central protein. Using systems biology contributed to the interpretation of data obtained in proteomic studies on MDD and expanded the findings of these studies. The combined use of these methodologies can provide new insights into the pathophysiology of psychiatric disorders, identifying novel biomarkers to improve diagnostic, prognostic, and treatment strategies in MDD.

Effects of selective serotonin reuptake inhibitors on platelet functions: a literature review

PURPOSE OF REVIEW

Many epidemiological studies have evidenced an increased bleeding risk associated with selective serotonin reuptake inhibitors (SSRIs), yet the underlying mechanisms remain unclear. This review summarizes data on SSRIs' effects on platelet functions assessed with assays used in clinical practice and highlights the areas that deserve further investigation.

RECENT FINDINGS

Conflicting results of SSRI effects on platelet aggregation were observed irrespectively of the agonist used, the antidepressant drug or the study type. Alike, discrepant results were reported with flow-cytometry-based assays assessing either platelet surface glycoprotein levels, integrin activation, agonist-induced secretion of intraplatelet granule content or membrane anionic phospholipid exposure. Other tests may have detected a platelet function defect in SSRIs samples, however, results were largely inconsistent.

SUMMARY

Critical literature examination unveils very low certainty of evidence on potential SSRI effect on platelet functions. Findings are often inconsistent even when similar methods are used, most likely because of differences in study design, included patients (age, comorbid conditions), SSRIs' type and dose, uncontrolled confounding factors, and statistical analysis power. Further studies are needed to disentangle any intrinsic antiplatelet effect of SSRIs and the multiple confounding factors, mainly the depression control itself and the degree of platelet SERT inhibition.

From blood to brain: Exploring the role of fibrinogen in the pathophysiology of depression and other neurological disorders

Recent findings indicate that fibrinogen, a protein involved in blood clotting, plays a significant role in neuroinflammation and mood disorders. Elevated fibrinogen levels are consistently observed in individuals with depression, potentially contributing to microglial activation. This could impair fibrinolysis and contribute to a pro-inflammatory environment in the brain. This neuroinflammatory response can impair neuroplasticity, a key process for learning, memory, and mood regulation. Fibrinogen may also indirectly influence neurotransmitters like serotonin, which play a vital role in mood regulation. Furthermore, fibrinogen's interaction with astrocytes may trigger a cascade of events leading to demyelination, a process where the protective sheath around nerve fibers deteriorates. This can disrupt communication within the nervous system and contribute to depression symptoms. Intriguingly, targeting fibrinogen or related pathways holds promise for therapeutic interventions. For instance, modulating PAI-1 (Plasminogen activator inhibitor-1) activity or inhibiting fibrinogen's interaction with brain cells could be potential strategies. This review explores the multifaceted relationship between fibrinogen and neurological disorders with a focus on depression highlighting its potential as a therapeutic target. Further research is necessary to fully elucidate the mechanisms underlying this association and develop effective therapeutic strategies targeting the fibrinolytic system for mood disorders.

Disruption of Lipid Profile, Glucose Metabolism, and Leptin Levels following Citalopram Administration and High-Carbohydrate and High-Cholesterol Diet in Mice

INTRODUCTION

Depression therapy has been linked to negative effects on energy metabolism, which can be attributed to various factors, including an ongoing inflammatory process commonly seen in metabolic disorders. Unhealthy lifestyle choices of patients and the impact of antidepressants on body weight and lipid and glucose metabolism also contribute to these metabolic side effects. Although not as pronounced as other psychopharmaceuticals, the increasing use of antidepressants raises concerns about their potential impact on public health. The study aimed to evaluate the short- and long-term effects of the antidepressant citalopram and its long-term combination with a special diet on metabolic parameters in mice.

METHODS

Animals were randomly divided into 5 groups - control, control + special diet, citalopram (10 mg/kg for 35 days), citalopram + special diet (10 mg/kg for 35 days), and citalopram (10 mg/kg for 7 days). After a described time of administration, animals were anesthetized, blood and fat and liver tissues were collected. Biochemical parameters of lipid metabolism (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) and glucose were analyzed using spectrophotometry and relevant adipokines and cytokines were evaluated by ELISA.

RESULTS

After a week of application of citalopram, we observed dyslipidemia that persisted even at the end of the 5-week experiment. Furthermore, after 5 weeks of citalopram administration, we observed a significant decrease in body weight gain and decreased leptin levels. Changes in lipid metabolism, higher levels of adipokines leptin and PAI-1 were observed due to the special diet after 5 weeks.

CONCLUSIONS

Our research suggests that the effects of citalopram and a diet on the metabolism of mice can be significant, both in the short term (1 week) and in the long term (5 weeks).

Infectious Diseases Society of America Guidelines on the Treatment and Management of Patients With COVID-19 (September 2022)

There are many pharmacologic therapies that are being used or considered for treatment of coronavirus disease 2019 (COVID-19), with rapidly changing efficacy and safety evidence from trials. The objective was to develop evidence-based, rapid, living guidelines intended to support patients, clinicians, and other healthcare professionals in their decisions about treatment and management of patients with COVID-19. In March 2020, the Infectious Diseases Society of America (IDSA) formed a multidisciplinary guideline panel of infectious disease clinicians, pharmacists, and methodologists with varied areas of expertise to regularly review the evidence and make recommendations about the treatment and management of persons with COVID-19. The process used a living guideline approach and followed a rapid recommendation development checklist. The panel prioritized questions and outcomes. A systematic review of the peer-reviewed and grey literature was conducted at regular intervals. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the certainty of evidence and make recommendations. Based on the most recent search conducted on 31 May 2022, the IDSA guideline panel has made 32 recommendations for the treatment and management of the following groups/populations: pre- and postexposure prophylaxis, ambulatory with mild-to-moderate disease, and hospitalized with mild-to-moderate, severe but not critical, and critical disease. As these are living guidelines, the most recent recommendations can be found online at: https://idsociety.org/COVID19guidelines. At the inception of its work, the panel has expressed the overarching goal that patients be recruited into ongoing trials. Since then, many trials were conducted that provided much-needed evidence for COVID-19 therapies. There still remain many unanswered questions as the pandemic evolved, which we hope future trials can answer.

Pathophysiological mechanisms of post-myocardial infarction depression: a narrative review

Myocardial infarction (MI) can have significant physical and mental consequences. Depression is a prevalent psychiatric condition after MI which can reduce the quality of life and increase the mortality rates of patients. However, the connection between MI and depression has remained under-appreciated. This review examines the potential connection between depression and MI by overviewing the possible pathophysiologic mechanisms including dysregulation of the hypothalamic-pituitary-adrenal axis and autonomic nervous system, coagulation system dysfunction, inflammation, environmental factors, as well as, genetic factors. Furthermore, depression can be an adverse event of medications used for MI treatment including beta-blockers, statins, or anti-platelet agents. The need for early detection and management of depression in patients with MI is, therefore, crucial for improving their overall prognosis. Adherence to treatments and regular follow-up visits can ensure the best response to treatment.

The Fibrinolytic System in Peripartum Depression

The relationship between depression and reduced fibrinolytic activity reflects the role of tissue plasminogen activator and plasmin in brain remodeling underlying resilience, depression remission, and reward processing, rather than the dissolution of fibrin clots. Individuals who experience depression demonstrate hippocampal and prefrontal cortex atrophy, as well as impaired neuronal connectivity. Brain-derived neurotrophic factor (BDNF), synthesized as a precursor that is activated through cleavage by tissue plasminogen activator and plasmin, influences adult neurogenesis and neuronal plasticity in the hippocampus and prefrontal cortex. Depression is associated with decreased brain levels of BDNF, due to reduced activity of tissue plasminogen activator and plasmin. Tissue plasminogen activator and plasmin also mediate the release of dopamine, a neurotransmitter implicated in motivation and reward. Peripartum depression defines a depressive episode that occurs during pregnancy or in the first month after delivery, reinforcing the concept that postpartum depression may be a continuum of antenatal depression. This article describes the fibrinolytic status in the healthy brain, in stress and depression, emphasizing the links between biological markers of depression and defective fibrinolysis. It also discusses the association between hypofibrinolysis and risk factors for perinatal depression, including polycystic ovary syndrome, early miscarriage, preeclampsia, stressful life events, sedentariness, eating habits, gestational and type 2 diabetes, and antithyroid peroxidase antibodies. In addition, it reviews the evidence that antidepressant medications and interventions as diverse as placebo, psychotherapy, massage, video game playing, regular exercise, dietary modifications, omega 3 fatty acid supplementation, neurohormones, and cigarette smoking may reduce depression by restoring the fibrinolytic activity. Last, it suggests new directions for research.

Mechanisms affecting brain remodeling in depression: do all roads lead to impaired fibrinolysis?

Fibrinolysis occurs when plasminogen activators, such as tissue plasminogen activator (tPA), convert plasminogen to plasmin, which dissolves the fibrin clot. The proteolytic activity of tPA and plasmin is not restricted to fibrin degradation. In the extravascular space, these two proteases modify a variety of substrates other than fibrin, playing a crucial role in physiological and pathological tissue remodeling. In the brain, for example, tPA and plasmin mediate the conversion of brain-derived neurotrophic factor precursor (proBDNF) to mature brain-derived neurotrophic factor precursor (BDNF). Thus, the fibrinolytic system influences processes reported to be dysfunctional in depression, including neurogenesis, synaptic plasticity, and reward processing. The hypothesis that decreased fibrinolytic activity is an important element in the pathogenesis of depression is supported by the association between depression and increased levels of plasminogen activator inhibitor (PAI)-1, the main inhibitor of tPA. Also, various biochemical markers of depression induce PAI-1 synthesis, including hypercortisolism, hyperinsulinemia, hyperleptinemia, increased levels of cytokines, and hyperhomocysteinemia. Moreover, hypofibrinolysis provides a link between depression and emotional eating, binge eating, vegetarianism, and veganism. This paper discusses the role of reduced fibrinolytic activity in the bidirectional interplay between depression and its somatic manifestations and complications. It also reviews evidence that abnormal fibrinolysis links heterogeneous conditions associated with treatment-resistant depression. Understanding the role of hypofibrinolysis in depression may open new avenues for its treatment.

High Perceived Stress May Shorten Activated Partial Thromboplastin Time and Lead to Worse Clinical Outcomes in Patients With Coronary Heart Disease

Objective: To determine the association of perceived stress with coagulation function and their predictive values for clinical outcomes. Methods: This prospective cohort study derived from a cross-sectional study for investigating the psychological status of inpatients with suspicious coronary heart disease (CHD). In this study, the 10-item Perceived Stress Scale (PSS-10) as an optional questionnaire was used to assess the severity of perceived stress. Coagulation function tests, such as activated partial thromboplastin time (APTT), prothrombin time (PT), and fibrinogen were measured within 1 h after admission. Furthermore, 241 patients with CHD out of 705 consecutive inpatients were included in the analyses and followed with a median of 26 months for the clinical outcomes. Results: The patients in high perceived stress status (PSS-10 score > 16) were with shorter APTT (36.71 vs. 38.45 s, p = 0.009). Shortened APTT ( ≤ 35.0 s) correlated with higher PSS-10 score (14.67 vs. 11.22, p = 0.003). The association of APTT with depression or anxiety was not found. Multiple linear models adjusting for PT estimated that every single point increase in PSS-10 was relevant to approximately 0.13 s decrease in APTT (p = 0.001) regardless of the type of CHD. APTT (every 5 s increase: hazard ratio (HR) 0.68 [0.47-0.99], p = 0.041) and perceived stress (every 5 points increase: HR 1.31 [1.09-1.58], p = 0.005) could predict the cardiovascular outcomes. However, both predictive values would decrease when they were simultaneously adjusted. After adjusting for the physical clinical features, the associated of perceived stress on cardiac (HR 1.25 [1.04-1.51], p = 0.020) and composite clinical outcomes (HR 1.24 [1.05-1.47], p = 0.011) persisted. Conclusions: For the patients with CHD, perceived stress strongly correlates with APTT. The activation of the intrinsic coagulation pathway is one of the mechanisms that high perceived stress causes cardiovascular events. This hints at an important role of the interaction of mental stress and coagulation function on cardiovascular prognosis. More attention needs to be paid to the patients with CHD with high perceived stress.

Alpha2-antiplasmin deficiency affects depression and anxiety-like behavior and apoptosis induced by stress in mice

OBJECTIVES

Depression is a psychiatric disorder that affects about 10% of the world's population and is accompanied by anxiety. Depression and anxiety are often caused by various stresses. However, the etiology of depression and anxiety remains unknown. It has been reported that alpha2-antiplasmin (α2AP) not only inhibits plasmin but also has various functions such as cytokine production and cell growth. This study aimed to determine the roles of α2AP on the stress-induced depression and anxiety.

METHODS

We investigated the mild repeated restraint stress-induced depressive and anxiety-like behavior in the α2AP^+/+ and α2AP^-/- mice using the social interaction test (SIT), sucrose preference test (SPT), and elevated plus maze (EPM).

RESULTS

The stresses such as the mild repeated restraint stress suppressed α2AP expression in the hippocampus of mice, and the treatment of fluoxetine (selective serotonin reuptake inhibitor [SSRI]) recovered the stress-caused α2AP suppression. We also showed that α2AP deficiency promoted the mild restraint stress-stimulated depression-like behavior such as social withdrawal and apathy and apoptosis in mice. In contrast, α2AP deficiency attenuated the mild restraint stress induced the anxiety-like behavior in mice.

CONCLUSIONS

α2AP affects the pathogenesis of depression and anxiety induced by stress.

Fluvoxamine: A Review of Its Mechanism of Action and Its Role in COVID-19

Fluvoxamine is a well-tolerated, widely available, inexpensive selective serotonin reuptake inhibitor that has been shown in a small, double-blind, placebo-controlled, randomized study to prevent clinical deterioration of patients with mild coronavirus disease 2019 (COVID-19). Fluvoxamine is also an agonist for the sigma-1 receptor, through which it controls inflammation. We review here a body of literature that shows important mechanisms of action of fluvoxamine and other SSRIs that could play a role in COVID-19 treatment. These effects include: reduction in platelet aggregation, decreased mast cell degranulation, interference with endolysosomal viral trafficking, regulation of inositol-requiring enzyme 1α-driven inflammation and increased melatonin levels, which collectively have a direct antiviral effect, regulate coagulopathy or mitigate cytokine storm, which are known hallmarks of severe COVID-19.

Antidepressants: bleeding or thrombosis?

The contribution of depression to the pathogenesis of cardiovascular disease includes autonomic disturbances, endothelial dysfunction, inflammation, smoking, sedentary lifestyle, carbohydrate craving, and impaired fibrinolysis. There is evidence that serotonergic antidepressants (selective serotonin reuptake inhibitors and serotonin and noradrenaline reuptake inhibitors) restore the fibrinolytic profile. Contrary to common belief, such antidepressants do not affect platelet aggregation induced by adenosine diphosphate or adrenaline but reduce platelet adhesion to collagen. Since platelet collagen receptor glycoprotein VI binds to fibrin, it is possible that fibrinolytic properties of serotonergic antidepressants could impair platelet adhesion to collagen. The profibrinolytic and antiplatelet properties of serotonergic antidepressants help explain the increased risk of gastrointestinal, intracranial, and surgical bleeding in patients using these medications. Studies evaluating the impact of antidepressants on thrombotic and cardiovascular risk have yielded contradictory results. Corroborating the hypothesis that serotonergic antidepressants have profibrinolytic and antiplatelet properties, some authors showed that these medications prevent both cardiovascular and thromboembolic events. Others showed an increased risk of ischemic stroke, cardiac events and thromboembolic disease. Silent brain infarction may present in some elders with depressive symptoms, so it is presumed that antidepressants are prescribed for subclinical stroke patients. Another explanation for the increased risk of cardiovascular and thromboembolic events reported by some authors in individuals taking antidepressants includes antidepressant side effects such as sedation and weight gain and depression comorbidities such as anxiety, obesity and hyperhomocysteinemia. In conclusion, we suggest that serotonergic antidepressants be considered weak anticoagulants. We also suggest that depressed patients with comorbidities increasing the risk of cardiovascular and thromboembolic disease be recommended to follow a balanced diet and engage in physical activity, such as daily walking.

Role of tissue plasminogen activator and plasminogen activator inhibitor as potential biomarkers in psychosis

The identification of biological markers for psychosis has an impact on its diagnosis, prognosis, and likelihood of treatment response. Tissue plasminogen activator (tPA) is involved in important functions such as synaptic plasticity, long-term potentiation and neurogenesis. Plasminogen activator inhibitor (PAI-1) is the most important inhibitor of tPA. Preliminary studies have shown that schizophrenia patients have lower tPA and higher PAI-1 levels than the general population. The association of tPA and PAI-1 abnormalities with psychotic spectrum disorders, however, remains elusive. Our primary objective was to assess the plasma levels of tPA and PAI-1 in patients experiencing acute psychotic episodes as compared to those in healthy controls. In this prospective case-control study, we collected peripheral blood samples from psychiatric inpatients and healthy age, gender and race-matched subjects and determined plasma levels of tPA and PAI-1 by enzyme-linked immune-absorbent assays. Plasma levels of PAI-1 in patients with schizoaffective disorder were significantly lower as compared to those in control subjects (P = 0.03). tPA was lower in cases as compared to controls although it did not reach statistical significance. Asian patients and controls had lower PAI-1 levels. Further, Asian patients with schizoaffective disorder had significantly lower PAI-1 level compared to Asian patients with schizophrenia. Our results indicate that patients with schizoaffective disorder have lower PAI-1 levels than those with schizophrenia, affective psychosis, and healthy controls. Further studies are warranted to explore the potential of PAI-1 as a biomarker for diagnosing schizoaffective disorder.

Neuro-Immune Hemostasis: Homeostasis and Diseases in the Central Nervous System

Coagulation and the immune system interact in several physiological and pathological conditions, including tissue repair, host defense, and homeostatic maintenance. This network plays a key role in diseases of the central nervous system (CNS) by involving several cells (CNS resident cells, platelets, endothelium, and leukocytes) and molecular pathways (protease activity, complement factors, platelet granule content). Endothelial damage prompts platelet activation and the coagulation cascade as the first physiological step to support the rescue of damaged tissues, a flawed rescuing system ultimately producing neuroinflammation. Leukocytes, platelets, and endothelial cells are sensitive to the damage and indeed can release or respond to chemokines and cytokines (platelet factor 4, CXCL4, TNF, interleukins), and growth factors (including platelet-derived growth factor, vascular endothelial growth factor, and brain-derived neurotrophic factor) with platelet activation, change in capillary permeability, migration or differentiation of leukocytes. Thrombin, plasmin, activated complement factors and matrix metalloproteinase-1 (MMP-1), furthermore, activate intracellular transduction through complement or protease-activated receptors. Impairment of the neuro-immune hemostasis network induces acute or chronic CNS pathologies related to the neurovascular unit, either directly or by the systemic activation of its main steps. Neurons, glial cells (astrocytes and microglia) and the extracellular matrix play a crucial function in a “tetrapartite” synaptic model. Taking into account the neurovascular unit, in this review we thoroughly analyzed the influence of neuro-immune hemostasis on these five elements acting as a functional unit (“pentapartite” synapse) in the adaptive and maladaptive plasticity and discuss the relevance of these events in inflammatory, cerebrovascular, Alzheimer, neoplastic and psychiatric diseases. Finally, based on the solid reviewed data, we hypothesize a model of neuro-immune hemostatic network based on protein–protein interactions. In addition, we propose that, to better understand and favor the maintenance of adaptive plasticity, it would be useful to construct predictive molecular models, able to enlighten the regulating logic of the complex molecular network, which belongs to different cellular domains. A modeling approach would help to define how nodes of the network interact with basic cellular functions, such as mitochondrial metabolism, autophagy or apoptosis. It is expected that dynamic systems biology models might help to elucidate the fine structure of molecular events generated by blood coagulation and neuro-immune responses in several CNS diseases, thereby opening the way to more effective treatments.

Procoagulant reactivity to laboratory acute mental stress in Africans and Caucasians, and its relation to depressive symptoms: The SABPA Study

The risk of cardiovascular disease is dramatically increasing in Africans (black). The prothrombotic stress response contributes to atherothrombotic disease and is modulated by depressive symptoms. We examined coagulation reactivity to acute mental stress and its relation to psychological well-being in Africans relative to Caucasians (white). A total of 102 African and 165 Caucasian school teachers underwent the Stroop Color-Word Conflict test. Circulating levels of von Willebrand factor (VWF) antigen, fibrinogen, and D-dimer were measured before and after the Stroop. Cardiovascular reactivity measures were also obtained. All participants completed the Patient Health Questionnaire-9 and the General Health Questionnaire-28 for the assessment of depressive symptoms and total psychological distress, respectively. After controlling for covariates, resting levels of VWF, fibrinogen, and D-dimer were higher in Africans than in Caucasians (all p-values ≤0.006). Depressive symptoms and psychological distress were not significantly associated with resting coagulation measures. Stress reactivity in VWF (p<0.001) and fibrinogen (p=0.016), but not in D-dimer (p=0.27), were decreased in Africans relative to Caucasians with Africans showing greater reactivity of total peripheral resistance (p=0.017). Depressive symptoms, but not general psychological distress, were associated with greater VWF increase (p=0.029) and greater fibrinogen decrease (p=0.030) in Africans relative to Caucasians. In conclusion, Africans showed greater hypercoagulability at rest but diminished procoagulant reactivity to acute mental stress when compared with Caucasians. Ethnic differences in the vascular adrenergic stress response might partially explain this finding. Depressive symptoms were associated with exaggerated VWF reactivity in Africans relative to Caucasians. The clinical implications of these findings for Africans need further study.

Neuro-Coagulopathy: Blood Coagulation Factors in Central Nervous System Diseases

Blood coagulation factors and other proteins, with modulatory effects or modulated by the coagulation cascade have been reported to affect the pathophysiology of the central nervous system (CNS). The protease-activated receptors (PARs) pathway can be considered the central hub of this regulatory network, mainly through thrombin or activated protein C (aPC). These proteins, in fact, showed peculiar properties, being able to interfere with synaptic homeostasis other than coagulation itself. These specific functions modulate neuronal networks, acting both on resident (neurons, astrocytes, and microglia) as well as circulating immune system cells and the extracellular matrix. The pleiotropy of these effects is produced through different receptors, expressed in various cell types, in a dose- and time-dependent pattern. We reviewed how these pathways may be involved in neurodegenerative diseases (amyotrophic lateral sclerosis, Alzheimer's and Parkinson's diseases), multiple sclerosis, ischemic stroke and post-ischemic epilepsy, CNS cancer, addiction, and mental health. These data open up a new path for the potential therapeutic use of the agonist/antagonist of these proteins in the management of several central nervous system diseases.

Role of tissue-type plasminogen activator and plasminogen activator inhibitor-1 in psychological stress and depression

Major depressive disorder is a common illness worldwide, but the pathogenesis of the disorder remains incompletely understood. The tissue-type plasminogen activator-plasminogen proteolytic cascade is highly expressed in the brain regions involved in mood regulation and neuroplasticity. Accumulating evidence from animal and human studies suggests that tissue-type plasminogen activator and its chief inhibitor, plasminogen activator inhibitor-1, are related to stress reaction and depression. Furthermore, the neurotrophic hypothesis of depression postulates that compromised neurotrophin brain-derived neurotrophic factor (BDNF) function is directly involved in the pathophysiology of depression. In the brain, the proteolytic cleavage of proBDNF, a BDNF precursor, to mature BDNF through plasmin represents one mechanism that can change the direction of BDNF action. We also discuss the implications of tissue-type plasminogen activator and plasminogen activator inhibitor-1 alterations as biomarkers for major depressive disorder. Using drugs that increase tissue-type plasminogen activator or decrease plasminogen activator inhibitor-1 levels may open new avenues to develop conceptually novel therapeutic strategies for depression treatment.

Molecular analysis of the mouse brain exposed to chronic mild stress: The influence of hepatocyte nuclear factor 4α on physiological homeostasis

Major depressive disorder (MDD) is a prevalent disorder that causes considerable disability in social functioning and is a risk factor for physical diseases. Recent clinical reports have demonstrated a marked association between MDD and physiological dyshomeostasis induced by metabolic disorders, including diabetes, hormone abnormalities and autoimmune diseases. The authors of the present study have previously analyzed comparative gene expression profiles in the prefrontal cortex (PFC) of a chronic mild stress (CMS) animal model of MDD. Hepatocyte nuclear factor 4α (Hnf4α) was identified as a central regulator that exerted significant influence on genes associated with physiological homeostasis. The aim of the present study was to investigate: i) the molecular mechanism of the depressive state in the PFC, and ii) the involvement of genes extracted from the comparative gene expression profiles, particularly those applicable to MDD in clinical practice. Core analysis of the previous PFC microarray results was performed using Ingenuity Pathway Analysis (IPA). Subsequently, IPA was used to search for molecules that are regulated by Hnf4α, and exist in the PFC and serum. From the core analysis, 5 genes that are associated with cell death and are expressed in the cortex were selected. Four of the extracted genes, insulin‑like growth factor 1, transthyretin, serpin family A member 3 and plasminogen, were markedly affected by Hnf4α. S100 calcium‑binding protein A9 (S100a9) and α2-HS-glycoprotein (Ahsg) were also chosen as they exist in serum and are also affected by Hnf4α. A significant group difference in the expression of these two genes was detected in the PFC, thalamus and hippocampus. The protein levels of AHSG and S100A9 in the PFC and hippocampus of the CMS group increased significantly when compared with the control group. These findings support the close association of Hnf4α (through genes such as S100a9 and Ahsg) with the development of various diseases induced by deregulation of physiological homeostasis during the progression of MDD.

The Extrinsic Coagulation Pathway: a Biomarker for Suicidal Behavior in Major Depressive Disorder

Although an association between major depressive disorder (MDD) and suicide exists, most depressed patients never attempt suicide. An improved understanding of the factors contributing to suicidal risk in MDD can provide direction for suicide predictor development. In MDD suicide attempters (MDD-SA), MDD non-attempters (MDD-NA), and healthy controls (HC) (n = 12 each group), complementary plasma proteomics identified 45 differential proteins mapped to coagulation and inflammation, 25 of which underwent Western blotting. In another cohort including antidepressant-treated patients (n = 49 each group), seven additional extrinsic pathway proteins were selected for ELISA. Two inflammatory proteins and eight coagulatory proteins demonstrated alterations in MDD-SA relative to MDD-NA and HC. Applying a relative mass-action ratio, MDD-SA subjects displayed a higher relative prothrombinase activity than MDD-NA subjects, while healthy controls displayed higher relative prothrombinase activity than both MDD-SA and MDD-NA subjects. Consistent with our human findings, we found that heparin treatment significantly increased forced swimming test (FST) immobility time in rodents. MDD, independent of suicidality, is associated with a proinflammatory state accompanied by a hypothrombotic state. Suicidal behavior in MDD is associated with a more pronounced proinflammatory and prothrombotic phenotype accompanied by extrinsic pathway activation, revealing an extrinsic pathway biomarker that can be applied in predicting and monitoring suicidal risk.

Prenatal stress-induced increases in hippocampal von Willebrand factor expression are prevented by concurrent prenatal escitalopram

Prenatal stress has been linked to deficits in neurological function including deficient social behavior, alterations in learning and memory, impaired stress regulation, and susceptibility to adult disease. In addition, prenatal environment is known to alter cardiovascular health; however, limited information is available regarding the cerebrovascular consequences of prenatal stress exposure. Vascular disturbances late in life may lead to cerebral hypoperfusion which is linked to a variety of neurodegenerative and psychiatric diseases. The known impact of cerebrovascular compromise on neuronal function and behavior highlights the importance of characterizing the impact of stress on not just neurons and glia, but also cerebrovasculature. Von Willebrand factor has previously been shown to be impacted by prenatal stress and is predictive of cerebrovascular health. Here we assess the impact of prenatal stress on von Willebrand factor and related angiogenic factors. Furthermore, we assess the potential protective effects of concurrent anti-depressant treatment during in utero stress exposure on the assessed cerebrovascular endpoints. Prenatal stress augmented expression of von Willebrand factor which was prevented by concurrent in utero escitalopram treatment. The functional implications of this increase in von Willebrand factor remain elusive, but the presented data demonstrate that although prenatal stress did not independently impact total vascularization, exposure to chronic stress in adulthood decreased blood vessel length. In addition, the current study demonstrates that production of reactive oxygen species in the hippocampus is decreased by prenatal exposure to escitalopram. Collectively, these findings demonstrate that the prenatal experience can cause complex changes in adult cerebral vascular structure and function.

Are the changes in the peripheral brain-derived neurotrophic factor levels due to platelet activation?

Brain-derived neurotrophic factor (BDNF) plays an important role in central nervous system development, neurogenesis and neuronal plasticity. BDNF is also expressed in several non-neuronal tissues, and it could play an important role in other processes, such as cancer, angiogenesis, etc. Platelets are the major source of peripheral BDNF. However, platelets also contain high amounts of serotonin; they express specific surface receptors during activation, and a multitude of pro-inflammatory and immunomodulatory bioactive compounds are secreted from the granules. Until recently, there was insufficient knowledge regarding the relationship between BDNF and platelets. Recent studies showed that BDNF is present in two distinct pools in platelets, in α-granules and in the cytoplasm, and only the BDNF in the granules is secreted following stimulation, representing 30% of the total BDNF in platelets. BDNF has an important role in the pathophysiology of depression. Low levels of serum BDNF have been described in patients with major depressive disorder, and BDNF levels increased with chronic antidepressant treatment. Interestingly, there is an association between depression and platelet function. This review analyzed studies that evaluated the relationship between BDNF and platelet activation and the effect of treatments on both parameters. Only a few studies consider this possible confounding factor, and it could be very important in diseases such as depression, which show changes in both parameters.

Serotonin reuptake inhibitors and post-gastrostomy bleeding: reevaluating the link

Introduction

Serotonin reuptake inhibitors (SRIs) are one of the most commonly prescribed classes of medications with a relatively safe side-effect profile. However, SRIs are being increasingly reported to be associated with bleeding complications in patients undergoing invasive procedures resulting from inhibition of serotonin reuptake by platelets and impaired platelet aggregation. The aim of our study was to determine whether there is an increased risk of post-percutaneous endoscopic gastrostomy (PEG) bleeding in patients exposed to SRIs after controlling for other mediations known to increase the risk of bleeding and major comorbidities.

Methods

This was a single-center cohort study that included who underwent PEG tube placement by standard pull-guidewire technique from July 2006 to June 2014. Patients were categorized into groups based on the medications (SRIs, aspirin, non-steroidal anti-inflammatory drugs, and anticoagulants) administered during the index hospitalization. The incidence of post-PEG bleeding was noted in two distinct post-procedure periods: within 48 hours, and between 48 hours and 14 days.

Results

A total of 637 PEG tube placements were done on 570 patients during the study period. There were 107 patients (18.8%) with major bleeding within 48 hours of PEG and 79 patients (13.9%) with major bleeding between 48 hours and 14 days. There was no significant increase in the post-PEG bleeding in patients taking a combination of an SRI along with aspirin or non-steroidal anti-inflammatory drugs. Patients on subcutaneous heparin for prophylaxis against thromboembolic events were more likely to have oozing at the PEG site requiring blood transfusion.

Conclusion

We did not notice an increase in post-PEG bleeding in patients on SRIs. However, in view of the limitation that our study is retrospective and that there are no known significant side effects of withdrawal of SRIs for a short duration, withholding SRIs could be a safe clinical option in patients undergoing PEG tube placement.

Hepatocyte nuclear factor 4 alpha is a key factor related to depression and physiological homeostasis in the mouse brain

Major depressive disorder (MDD) is a common psychiatric disorder that involves marked disabilities in global functioning, anorexia, and severe medical comorbidities. MDD is associated with not only psychological and sociocultural problems, but also pervasive physical dysfunctions such as metabolic, neurobiological and immunological abnormalities. Nevertheless, the mechanisms underlying the interactions between these factors have yet to be determined in detail. The aim of the present study was to identify the molecular mechanisms responsible for the interactions between MDD and dysregulation of physiological homeostasis, including immunological function as well as lipid metabolism, coagulation, and hormonal activity in the brain. We generated depression-like behavior in mice using chronic mild stress (CMS) as a model of depression. We compared the gene expression profiles in the prefrontal cortex (PFC) of CMS and control mice using microarrays. We subsequently categorized genes using two web-based bioinformatics applications: Ingenuity Pathway Analysis and The Database for Annotation, Visualization, and Integrated Discovery. We then confirmed significant group-differences by analyzing mRNA and protein expression levels not only in the PFC, but also in the thalamus and hippocampus. These web tools revealed that hepatocyte nuclear factor 4 alpha (Hnf4a) may exert direct effects on various genes specifically associated with amine synthesis, such as genes involved in serotonin metabolism and related immunological functions. Moreover, these genes may influence lipid metabolism, coagulation, and hormonal activity. We also confirmed the significant effects of Hnf4a on both mRNA and protein expression levels in the brain. These results suggest that Hnf4a may have a critical influence on physiological homeostasis under depressive states, and may be associated with the mechanisms responsible for the interactions between MDD and the dysregulation of physiological homeostasis in humans.

Coagulation and mental disorders

The neurovascular unit is a key player in brain development, homeostasis, and pathology. Mental stress affects coagulation, while severe mental illnesses, such as recurrent depression and schizophrenia, are associated with an increased thrombotic risk and cardiovascular morbidity. Evidence indicates that the hemostatic system is involved to some extent in the pathogenesis, morbidity, and prognosis of a wide variety of psychiatric disorders. The current review focuses on emerging data linking coagulation and some psychiatric disorders.

Elevated plasma fibrinogen, psychological distress, antidepressant use, and hospitalization with depression: two large population-based studies

OBJECTIVES

Low-grade systemic inflammation may contribute to the development of depression. We tested the hypothesis that elevated plasma levels of the inflammatory marker fibrinogen are associated with psychological distress, use of antidepressant medication, and with hospitalization with depression in the general population.

METHODS

We examined 73,367 20-100 year old men and women from two large population-based studies, the Copenhagen General Population Study and the Copenhagen City Heart Study. We measured plasma fibrinogen and recorded symptoms of psychological distress, use of antidepressant medication, and hospitalization with depression in both cross-sectional and prospective studies.

RESULTS

In cross-sectional analyses, a stepwise increase in fibrinogen percentile categories was associated with a stepwise increase in risk of psychological distress, use of antidepressant medication, and hospitalization with depression (p-trend 2×10(-11) to 5×10(-95)). Furthermore, when different classes of antidepressant medication were examined, a stepwise increase in fibrinogen percentile categories was associated with a stepwise increase in risk of use of Selective Serotonin Reuptake Inhibitors and Tricyclic Antidepressants (p-trend 7×10(-18) and 6×10(-7), respectively). In prospective analyses, stepwise increasing fibrinogen percentile categories also associated with stepwise increasing risk of hospitalization with depression (p-trend=7×10(-6)): age and gender adjusted hazard ratios were 1.13 (95% confidence interval 0.70-1.83) for the 25.1-50th percentiles, 1.53 (0.97-2.42) for the 50.1-75th percentiles, 1.82 (1.11-2.97) for the 75.1-90th percentiles, 2.10 (1.12-3.95) for the 90.1-95th percentiles, and 3.23 (1.79-5.85) for the >95th percentiles, versus the 0-25th percentiles.

CONCLUSION

Elevated levels of fibrinogen were associated with psychological distress, use of antidepressant medication, and with hospitalization with depression in 73,367 individuals from the general population, in cross-sectional studies and in prospective studies for hospitalization with depression.

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.

Can activation of coagulation and impairment of fibrinolysis in patients with anxiety and depression be reversed after improvement of psychiatric symptoms? Results of a pilot study

Anxiety and depression are associated with an activation of coagulation and impairment of fibrinolysis. This study addresses the question whether these findings are reversed after psychotherapy and improvement of psychiatric symptoms. Three factors of coagulation and fibrinolysis as well as level of anxiety and depression were reassessed in 12 patients 1 to 3 years after intensive inpatient psychotherapy. The patients showed a substantial improvement of their severe anxiety disorder and comorbid depressive disorder. Simultaneously, we found a significant decrease in factor VII and plasminogen activator inhibitor. We conclude that reduction of severe anxiety and depression may be associated with a reversal of the procoagulant effect (activation of coagulation and impairment of fibrinolysis) of these psychological states. Because of the small sample size of this pilot study, further research is needed.