Inflammation and depression: why poststroke depression may be the norm and not the exception

Peripheral inflammation and trajectories of depressive symptomology after ischemic stroke: A prospective cohort study

BACKGROUND

Understanding the association of peripheral inflammation and post-stroke depressive symptomology (PSDS) might provide further insights into the complex etiological mechanism of organic depression. However, studies focusing on the longitudinal patterns of PSDS were limited and it remained unclear whether peripheral inflammation influences the occurrence and development of PSDS.

METHODS

A total of 427 prospectively enrolled and followed ischemic stroke patients were included in the analytical sample. Depressive symptomology was assessed on four occasions during 1 year after ischemic stroke. Peripheral inflammatory proteins on admission and repeated measures of peripheral immune markers in three stages were collected. Latent class growth analysis (LCGA) was employed to delineate group-based trajectories of peripheral immune markers and PSDS. Multinomial regression was performed to investigate the association of peripheral inflammation with PSDS trajectories.

RESULTS

Four distinct trajectories of PSDS were identified: stable-low (n = 237, 55.5 %), high-remitting (n = 120, 28.1 %), late-onset (n = 44, 10.3 %), and high-persistent (n = 26, 6.1 %) PSDS trajectories. The elevation of peripheral fibrinogen on admission increased the risk of high-persistent PSDS in patients with early high PSDS. Additionally, chronic elevation of innate immune levels might not only increase the risk of high-persistent PSDS in patients with early high PSDS but also increase the risk of late-onset PSDS in patients without early high PSDS. The elevation of adaptive immune levels in the convalescence of ischemic stroke may contribute to the remission of early high PSDS.

CONCLUSIONS

Peripheral immunity could influence the development of PSDS, and this influence might have temporal heterogeneity. These results might provide vital clues for the inflammation hypothesis of PSD.

Impact of Baduanjin exercise combined with rational emotive behavior therapy on sleep and mood in patients with poststroke depression: A randomized controlled trial

BACKGROUND

Poststroke depression (PSD) is one of the most common stroke complications. It not only leads to a decline in patients' quality of life but also increases the mortality of patients. In this study, the method of combining Chinese traditional exercise Baduanjin with psychotherapy was used to intervene in patients with PSD and to explore the improvement of sleep, mood, and serum levels of brain-derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT), and interleukin-6 (IL-6) levels in patients with PSD by combined treatment.

METHODS

A total of 100 patients with PSD who met the inclusion criteria were randomly assigned to Baduanjin group (n = 50) or control group (n = 50). The control group received treatment with escitalopram oxalate and rational emotive behavior therapy, while the experimental group received Baduanjin training in addition to the treatment given to the control group. Changes in sleep efficiency, sleep total time, sleep latency, arousal index, Hamilton Anxiety Rating Scale, Hamilton Depression Scale score, serum BDNF, 5-HT, IL-6 levels, and Modified Barthel Index were measured at baseline, 4 weeks and 8 weeks after intervention, and the results were compared between the 2 groups.

RESULTS

Significantly improvements in the sleep efficiency, sleep total time, serum 5-HT, BDNF levels, and Modified Barthel Index score were detected at week 4 in the Baduanjin group than in the control group (P < .05). Additionally, the sleep latency, arousal index, Hamilton Anxiety Rating Scale, Hamilton Depression Scale scores and IL-6 levels in the Baduanjin group were lower than those in the control group (P < .05). After 8 weeks of treatment, the above indexes in the Baduanjin group were further improved compared with the control group (P < .05), and the above indexes of the 2 groups were significantly improved compared with the baseline (P < .001).

CONCLUSION

Baduanjin exercise combined with rational emotive behavior therapy effectively improves the mood and sleep status of patients with PSD; It increases the serum levels of 5-HT and BDNF while reducing the level of serum proinflammatory factor IL-6; additionally, the intervention alleviates the degree of neurological impairment, upgrades the ability of daily living, and improves the quality of life.

Exploring the bi-directional relationship and shared genes between depression and stroke via NHANES and bioinformatic analysis

Background: Stroke and depression are the two most common causes of disability worldwide. Growing evidence suggests a bi-directional relationship between stroke and depression, whereas the molecular mechanisms underlying stroke and depression are not well understood. The objectives of this study were to identify hub genes and biological pathways related to the pathogenesis of ischemic stroke (IS) and major depressive disorder (MDD) and to evaluate the infiltration of immune cells in both disorders. Methods: Participants from the United States National Health and Nutritional Examination Survey (NHANES) 2005-2018 were included to evaluate the association between stroke and MDD. Two differentially expressed genes (DEGs) sets extracted from GSE98793 and GSE16561 datasets were intersected to generate common DEGs, which were further screened out in cytoHubba to identify hub genes. GO, KEGG, Metascape, GeneMANIA, NetworkAnalyst, and DGIdb were used for functional enrichment, pathway analysis, regulatory network analysis, and candidate drugs analysis. ssGSEA algorithm was used to analyze the immune infiltration. Results: Among the 29706 participants from NHANES 2005-2018, stroke was significantly associated with MDD (OR = 2.79,95% CI:2.26-3.43, p < 0.0001). A total of 41 common upregulated genes and eight common downregulated genes were finally identified between IS and MDD. Enrichment analysis revealed that the shared genes were mainly involved in immune response and immune-related pathways. A protein-protein interaction (PPI) was constructed, from which ten (CD163, AEG1, IRAK3, S100A12, HP, PGLYRP1, CEACAM8, MPO, LCN2, and DEFA4) were screened. In addition, gene-miRNAs, transcription factor-gene interactions, and protein-drug interactions coregulatory networks with hub genes were also identified. Finally, we observed that the innate immunity was activated while acquired immunity was suppressed in both disorders. Conclusion: We successfully identified the ten hub shared genes linking the IS and MDD and constructed the regulatory networks for them that could serve as novel targeted therapy for the comorbidities.

C-Reactive Protein and Specific Depression Symptoms Among Older Adults: An Exploratory Investigation of Multi-Plane Networks Using Cross-Sectional Data From NHANES (2017-2020)

INTRODUCTION

Studies investigating the association between C-reactive protein (CRP) and depression among older adults have yielded inconsistent results. We suspect that this may be due to varying associations between CRP and particular depression symptom criteria, and we addressed this challenge using network analysis.

METHODS

We used cross-sectional data from prepandemic National Health and Nutrition Examination Survey questionnaires (2017-2020) and included a sample of 1698 adults aged 65 years or older. Depression symptoms were assessed using the Patient Health Questionnaire-9. Unregularized Mixed Graphical Models were estimated using the R package mgm before and after adjusting for relevant sociodemographic, clinical, and lifestyle covariates.

RESULTS

In the model with no covariates, the only symptom criterion associated with CRP was "appetite problems." This association remained robust after controlling for all covariates. Although not associated with CRP, other criteria such as "fatigue" and "concentration difficulty" showed associations with important covariates for older adults such as white blood cell count or hemoglobin, respectively.

DISCUSSION

The CRP-related variability in the depression symptom network that we have demonstrated may help explain the reported inconsistencies. The present study stands as exploratory, and future research should focus on applying longitudinal designs and including several other inflammatory proteins and covariates that were not measured in the current network model.

Kinematic Studies of the Go/No-Go Task as a Dynamic Sensorimotor Inhibition Task for Assessment of Motor and Executive Function in Stroke Patients: An Exploratory Study in a Neurotypical Sample

Inhibition of reaching and grasping actions as an element of cognitive control and executive function is a vital component of sensorimotor behaviour that is often impaired in patients who have lost sensorimotor function following a stroke. To date, there are few kinematic studies detailing the fine spatial and temporal upper limb movements associated with the millisecond temporal trajectory of correct and incorrect responses to visually driven Go/No-Go reaching and grasping tasks. Therefore, we aimed to refine the behavioural measurement of correct and incorrect inhibitory motor responses in a Go/No-Go task for future quantification and personalized rehabilitation in older populations and those with acquired motor disorders, such as stroke. An exploratory study mapping the kinematic profiles of hand movements in neurotypical participants utilizing such a task was conducted using high-speed biological motion capture cameras, revealing both within and between subject differences in a sample of healthy participants. These kinematic profiles and differences are discussed in the context of better assessment of sensorimotor function impairment in stroke survivors.

Western diet associated with increased post-stroke depressive symptoms

The present study examines the association of diet with depressive symptoms among stroke survivors from a community cohort of older adults. Depression is common after stroke. A healthy diet has previously been associated with fewer depressive symptoms in older individuals, but it is unknown if this effect is also seen in stroke survivors. Eighty-six participants from the Memory and Aging Project with a history of stroke at their study baseline enrolment, complete dietary data and two or more assessments for depression were included in this observational prospective cohort analysis. Depressive symptoms were assessed annually with a 10-item version of the Center for Epidemiologic Studies Depression scale. Diet was assessed using a validated food-frequency questionnaire administered at baseline. Diet scores were based on analysis of participants' reported intakes of 144 food items. A generalised estimating equation (GEE) model was applied to examine the association of diet score with depressive symptoms. The study participants had a mean age of 82 ± 7⋅17 years and 14⋅42 ± 2⋅61 years of education, and 82⋅56 % were female. Western diet score was positively associated with depressive symptoms over time (diet score tertile 3 v. tertile 1: β = 0⋅22, se = 0⋅09, P = 0⋅02; P for trend = 0⋅022). Interaction with sex suggested a stronger effect in females. A Western diet was associated with more post-stroke depressive symptoms, suggesting nutrition is important not only for reducing cerebrovascular risk, but for protecting post-stoke mental health as well.

Natural Products for the Treatment of Post-stroke Depression

Post-stroke depression (PSD) is the most frequent and important neuropsychiatric consequence of stroke. It is strongly associated with exacerbated deterioration of functional recovery, physical and cognitive recoveries, and quality of life. However, its mechanism is remarkably complicated, including the neurotransmitters hypothesis (which consists of a monoaminergic hypothesis and glutamate-mediated excitotoxicity hypothesis), inflammation hypothesis, dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, and neurotrophic hypothesis and neuroplasticity. So far, the underlying pathogenesis of PSD has not been clearly defined yet. At present, selective serotonin reuptake inhibitors (SSRIs) have been used as the first-line drugs to treat patients with PSD. Additionally, more than SSRIs, a majority of the current antidepressants complied with multiple side effects, which limits their clinical application. Currently, a wide variety of studies revealed the therapeutic potential of natural products in the management of several diseases, especially PSD, with minor side effects. Accordingly, in our present review, we aim to summarize the therapeutic targets of these compounds and their potential role in-clinic therapy for patients with PSD.

Repetitive xenon treatment improves post-stroke sensorimotor and neuropsychiatric dysfunction

Stroke is a life-changing event as stroke survivors experience changes in personality, emotions and mood. We investigated the effect of xenon gas encapsulated in liposomes on stroke-generated sensorimotor impairments, and anxiety- and depression-like phenotypes. Ischemic stroke was created by the intraluminal middle cerebral artery occlusion (MCAO) for 6 h followed by reperfusion in rats. Xenon-liposome (6 mg/kg, intravenous) treatment was given multiple times starting at 2 h post-ischemia through 6 h (5X), and once-daily for next 3 days. Rats underwent ischemic injury displayed sensorimotor deficits in the adhesive removal, vibrissae-evoked forelimb placement and rotarod tests. These animals also made lesser entries and spent less time on open arms of the elevated-plus maze and swam more in passive mode in the forced swimming test, indicating anxiety- and depression-like behaviors at 28- and 35-days post-injury, respectively. Repeated intravenous treatment with xenon-liposomes ameliorated these behavioral aberrations (p < 0.05). Gut microbiome analysis (16S ribosomal-RNA gene sequencing) showed a decrease in the Clostridium clusters XI, XIVa, XVIII and Lactobacillus bacterium, and increase of the Prevotella in the xenon-liposome group. No microbiota communities were majorly affected across the treatments. Moreover, xenon treatment group showed augmented plasma levels of IL-6 cytokines (∼5 fold) on day-35 post-ischemia, while no change was noticed in the IL-1β, IL-4, IL-10, IL-13 and MCP-1 levels. Our data highlights the safety, behavioral recovery and reversal of post-stroke brain injury following xenon-liposome treatment in an extended ischemic model. These results show the potential for this treatment strategy to be translated to patients with stroke.

Vision and Visuomotor Performance Following Acute Ischemic Stroke

Background

As measurable sensory and motor deficits are key to the diagnosis of stroke, we investigated the value of objective tablet based vision and visuomotor capacity assessment in acute mild-moderate ischemic stroke (AIS) patients.

Methods

Sixty AIS patients (65 ± 14 years, 33 males) without pre-existing visual/neurological disorders and acuity better than 6/12 were tested at their bedside during the first week post-stroke and were compared to 40 controls (64 ± 11 years, 15 males). Visual field sensitivity, quantified as mean deviation (dB) and visual acuity (with and without luminance noise), were tested on MRFn (Melbourne Rapid Field-Neural) iPad application. Visuomotor capacity was assessed with the Lee-Ryan Eye-Hand Coordination (EHC) iPad application using a capacitive stylus for iPad held in the preferred hand.Time to trace 3 shapes and displacement errors (deviations of >3.5 mm from the shape) were recorded. Diagnostic capacity was considered with Receiver Operating Characteristics. Vision test outcomes were correlated with National Institutes of Health Stroke Scale (NIHSS) score at the admission.

Results

Of the 60 AIS patients, 58 grasped the iPad stylus in their preferred right hand even though 31 had left hemisphere lesions. Forty-one patients (68%) with better than 6/12 visual acuity (19 right, 19 left hemisphere and 3 multi-territorial lesions) returned significantly abnormal visual fields. The stroke group took significantly longer (AIS: 93.4 ± 60.1 s; Controls: 33.1 ± 11.5 s, p < 0.01) to complete EHC tracing and made larger displacements (AIS: 16,388 ± 36,367 mm; Controls: 2,620 ± 1,359 mm, p < 0.01) although both control and stroke groups made similar numbers of errors. EHC time was not significantly different between participants with R (n = 26, 84.3 ± 55.3 s) and L (n = 31, 101.3 ± 64.7 s) hemisphere lesions. NIHSS scores and EHC measures showed low correlations (Spearman R: −0.15, L: 0.17). ROC analysis of EHC and vision tests found high diagnostic specificity and sensitivity for a fail at EHC time, or visual field, or Acuity-in-noise (sensivity: 93%, specificity: 83%) that shows little relationship to NIHSS scores.

Conclusions

EHC time and vision test outcomes provide an easy and rapid bedside measure that complements existing clinical assessments in AIS. The low correlation between visual function, NIHSS scores and lesion site offers an expanded clinical view of changes following stroke.

Acute Routine Leukocyte and Neutrophil Counts Are Predictive of Poststroke Recovery at 3 and 12 Months Poststroke: An Exploratory Study

Background and Aims. White blood cell (WBC) and neutrophil counts (NC) are common markers of inflammation and neurological stroke damage and could be expected to predict poststroke outcomes. Objective. The aim of this study was to explore the prognostic value of early poststroke WBC and NC to predict cognition, mood, and disability outcomes at 3 and 12 months poststroke. Methods. Routine clinical analyses WBC and NC were collected at 3 time points in the first 4 days of hospitalization from 156 acute stroke patients. Correlations using hierarchical or ordinal regressions were explored between acute WBC and NC and functional recovery, depression, and cognition at 3 and 12 months poststroke, after covarying for age and baseline stroke severity. Results. We found significant increases in NC between <12 hours and 24 to 48 hours time points (P = .05). Hierarchical regressions, covaried for age and baseline stroke severity, found that 24 to 48 hours WBC (P = .05) and NC (P = .04) significantly predicted 3-month cognition scores. Similarly, 24 to 48 hours WBC (P = .05) and NC (P = .02) predicted cognition scores at 12 months. Increases in WBC and NC were predictive of increased cognition scores at both 3 and 12 months (positive recovery) though there were no significant associations between WBC and NC and disability or depression scores. Conclusions. Routine acute stroke clinical laboratory tests such as WBC and NC taken between 24 and 48 hours poststroke are predictive of cognition poststroke. It is interpreted that higher rapid immunological activation in the acute phase is an indicator for the trajectory of positive stroke recovery.

Higher levels of C-reactive protein in the acute phase of stroke indicate an increased risk for post-stroke depression: A systematic review and meta-analysis

BACKGROUND

Investigations have revealed the association between inflammation and post-stroke depression (PSD). However, whether the C-reactive protein (CRP) level, a biomarker of inflammation, would affect the development of PSD is still controversial.

METHODS

A systematic search of databases was performed for eligible studies. Standardized Mean Difference (SMD) with 95 % Confidence Interval (CI) was used to assess the association between the CRP level in the acute phase of stroke and the risk of PSD.

RESULTS

13 cohort studies that involved 3536 participants were included. Combined results showed that compared with non-PSD patients, the CRP level of PSD patients was significantly higher on admission (SMD = 0.19, 95 % CI: 0.12-0.27). A subgroup analysis by classifying the assessment time of depression showed obvious differences of the CRP levels between the PSD patients who were diagnosed more than 1 month after stroke and the non-PSD (1-3 months: SMD = 0.16, 95 % CI: 0.06-0.25; >3months: SMD = 0.34, 95 % CI: 0.18-0.51).

CONCLUSION

A higher level of CRP in the acute phase of stroke suggests an increased risk for PSD.

CDDO-Im exerts antidepressant-like effects via the Nrf2/ARE pathway in a rat model of post-stroke depression

Increasing evidence suggests that oxidative damage and neuroinflammation play a critical role in the pathogenesis of post-stroke depression (PSD). These pathologic processes are tightly regulated by the NF-E2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway. The synthetic triterpenoid, 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im), is a potent Nrf2 activator. This study investigated whether CDDO-Im exhibited antidepressant-like activity and elucidated its protective mechanisms in a rat model of PSD, which was produced by middle cerebral artery occlusion (MCAO) followed by 28 days of chronic unpredictable mild stress (CUMS) in conjunction with solitary housing. The results demonstrated that CDDO-Im treatment markedly improved the depressive-like behaviors and reduced neuronal cell loss in the hippocampus, through decreasing the malondialdehyde (MDA) content (indicative of lipid peroxidation), superoxide dismutase (SOD), NF-kB activation, interleukin-6 (IL-6) and interleukin-1b (IL-1β) in PSD rats. CDDO-Im treatment alleviated the oxidative stress and inflammatory response in PSD rats by promoting Nrf2 nuclear import and increasing the protein levels of Nrf2 downstream target genes, including heme oxygenase-1(HOMX1) and, quinone oxidoreductase-1(NQO1).These findings suggested that CDDO-Im treatment exhibited antidepressant-like effects and protected PSD rats from oxidative and inflammatory injury via the Nrf2/ARE pathway. Therefore, CDDO-Im treatment is worthy of further study.

Susceptibility of Women to Cardiovascular Disease and the Prevention Potential of Mind-Body Intervention by Changes in Neural Circuits and Cardiovascular Physiology

Women have been reported to be more vulnerable to the development, prognosis and mortality of cardiovascular diseases, yet the understanding of the underlying mechanisms and strategies to overcome them are still relatively undeveloped. Studies show that women's brains are more sensitive to factors affecting mental health such as depression and stress than men's brains. In women, poor mental health increases the risk of cardiovascular disease, and conversely, cardiovascular disease increases the incidence of mental illness such as depression. In connection with mental health and cardiovascular health, the presence of gender differences in brain activation, cortisol secretion, autonomic nervous system, vascular health and inflammatory response has been observed. This connection suggests that strategies to manage women's mental health can contribute to preventing cardiovascular disease. Mind-body interventions, such as meditation, yoga and qigong are forms of exercise that strive to actively manage both mind and body. They can provide beneficial effects on stress reduction and mental health. They are also seen as structurally and functionally changing the brain, as well as affecting cortisol secretion, blood pressure, heart rate variability, immune reactions and reducing menopausal symptoms, thus positively affecting women's cardiovascular health. In this review, we investigate the link between mental health, brain activation, HPA axis, autonomic nervous system, blood pressure and immune system associated with cardiovascular health in women and discuss the effects of mind-body intervention in modulating these factors.

Psychobiological mechanisms underlying the mood benefits of meditation: A narrative review

Psychological stressors can lead to distress and result in autonomic arousal and activation of a stress response. Ongoing or persistent stress can disrupt the stress response feedback mechanisms and result in elevated cortisol and pro-inflammatory cytokines which can cause damage to brain regions involved in the regulation of mood and emotion. We propose that the magnitude of the stress response experienced in response to psychological stressors depends on a number of modifiable psychological processes including an individual’s level of self-compassion, dispositional mindfulness, tendency to ruminate and attentional bias. We further propose that the stress response elected by psychological stressors can be meditated by influencing these modifiable psychological processes, and that meditation practices can decrease stress and improve mood by decreasing stress reactivity on a psychological, physiological and neurobiological level. We explore this in a narrative review.

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Meditation decreases blood pressure, heart rate, cortisol and cytokine levels.

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Meditation increases self-compassion, dispositional mindfulness and meta-cognition.

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Meditation improves attention and memory.

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Meditation results in brain changes in regions related to emotion regulation.

Understanding Why Post-Stroke Depression May Be the Norm Rather Than the Exception: The Anatomical and Neuroinflammatory Correlates of Post-Stroke Depression

Ischemic Stroke precedes depression. Post-stroke depression (PSD) is a major driver for poor recovery, negative quality of life, poor rehabilitation outcomes and poor functional ability. In this systematic review, we analysed the inflammatory basis of post-stroke depression, which involves bioenergetic failure, deranged iron homeostasis (calcium influx, Na influx, potassium efflux etc), excitotoxicity, acidotoxicity, disruption of the blood brain barrier, cytokine-mediated cytotoxicity, reactive oxygen mediated toxicity, activation of cyclooxygenase pathway and generation of toxic products. This process subsequently results in cell death, maladapted, persistent neuro-inflammation and deranged neuronal networks in mood-related brain regions. Furthermore, an in-depth review likewise reveals that anatomic structures related to post-stroke depression may be localized to complex circuitries involving the cortical and subcortical regions.

Gadd45b is a novel mediator of depression-like behaviors and neuroinflammation after cerebral ischemia

BACKGROUND

Poststroke depression (PSD) is an important consequence after stroke, with a negative impact on stroke outcome. Recent evidence points to a modulatory role of Growth arrest and DNA-damage-inducible protein 45 beta (Gadd45b) in depression. Herein, we evaluated the antidepressant efficacy and mechanism underlying the potent therapeutic effects of Gadd45b after cerebral ischemia.

METHODS

Adult male Sprague-Dawley rats were subjected to cerebral ischemia by permanent middle cerebral artery occlusion (MCAO). The sucrose preference test (SPT), forced swim test (FST), and tail suspension test (TST) were performed after completing MCAO to study the antidepressant-like effects. The expression of brain-derived neurotrophic factor (BDNF) and neuroinflammation were determined in the hippocampus.

RESULTS

We showed that Gadd45b knockdown induced depression-like behaviors after cerebral ischemia, including increased immobility time in the FST and TST and reduced sucrose preference. Gadd45b knockdown enhanced the expression of pro-inflammatory cytokines IL-6 and TNF-α, accompanying with decreased protein levels of BDNF in the hippocampus. Moreover, the levels of phosphorylated ERK and CREB, which have been implicated in events downstream of BDNF signaling, were also decreased after cerebral ischemia.

CONCLUSION

Hence, the results showed that Gadd45b is a promising drug candidate for treating PSD and possibly other nervous system diseases associated with neuroinflammation. Gadd45b may have therapeutic potential for PSD through BDNF-ERK-CREB pathway and neuroinflammation.

Influence of inflammatory status in the acute phase of stroke on post-stroke depression

BACKGROUND

Thirty percent of stroke patients will suffer from post-stroke depression (PSD). Recent data suggest that inflammation accounts for a substantial amount of depression. Our primary objective was to assess the association between standard inflammation biomarkers in the acute phase of stroke and PSD at three months. The secondary objective was to elaborate a predictive model of PSD from clinical, biological and radiological data.

METHODS

We performed a retrospective analysis of a single-centre cohort of stroke patients with a three-month follow-up. Serum levels of C-reactive protein (CRP), fibrinogen, leukocyte count and neutrophil to lymphocyte ratio (NLR) were tested at admission and at peak. Mood was assessed at three months using the depression sub-scale of the Hospital Anxiety and Depression Scale (HADS). Association between inflammation biomarkers and HADS was evaluated with multi-linear regression adjusted on clinical and radiological parameters. Logistic predictive models of PSD at three months, with and without inflammation biomarkers, were compared.

RESULTS

Three hundred and forty-eight patients were included, of whom 20.06% developed PSD. Baseline and peak values of all inflammatory markers were associated with the severity of PSD at three months. Area under the curve for the receiver operating characteristic curve of PSD prediction was 0.746 (CI 95% 0.592-0.803) with selected inflammation biomarkers and 0.744 (CI 95% 0.587-0.799) without.

CONCLUSION

Most inflammation biomarkers are weakly associated with PSD, adding negligible value to predictive models. While they suggest the implication of inflammation in PSD pathogenesis, they are useless for the prediction of PSD, underscoring the need for more specific biomarkers.

Carotid artery stenosis and inflammatory biomarkers: the role of inflammation-induced immunological responses affecting the vascular systems

The death, disability and economic cost of stroke are enormous. Indeed, among the 16 million people worldwide who suffer a stroke' annually, nearly six million die, and another five million are left permanently disabled making prevention of stroke one of the most important priorities in healthcare. Currently carotid artery stenosis (CS) or narrowing of the common carotid artery (CCA) or internal carotid artery (ICA) due to atherosclerotic plaque, accounts for 20-30% of all ischemic strokes. Atherosclerosis is now regarded as a chronic inflammatory disease in response to vascular compromise especially from hypertension. This has long been known to lead to inflammation and atherosclerotic plaque formation in the blood vessels. This mini-review aims to highlight the role of inflammation and neuro-immunological processes in carotid artery disease. Various cellular elements of inflammation and advanced imaging techniques have been identified as potential markers of plaque progression. Therapies related to decreasing and modulating immune-responsive inflammation in the carotid vessels have been shown to translate into decreased occurrence of acute neurologic events and improvement of clinical outcomes.

Meditation and Endocrine Health and Wellbeing

Meditation is a popular practice for reducing stress and improving mental health and wellbeing. Its effects are mediated largely by the endocrine system, including the hypothalamic-pituitary-adrenal axis, the hypothalamic-pituitary-thyroid axis, and the renin-angiotensin-aldosterone system, and energy homeostasis. The limited evidence available indicates that changes associated with endocrine function following meditation correspond with improvements in mental health. However, this field of study is hampered by a lack of consensus as to definition and types of meditation and the mixed quality of reported studies. Moreover, the exact mechanisms by which meditation operates remain unclear and more robust studies are required to explore this by delineating the target populations, forms, dosages, and modes of delivery of meditation, comparison groups, and health experiences and outcomes used.

Role of vinpocetine in ischemic stroke and poststroke outcomes: A critical review

Vinpocetine (VPN) is a synthetic ethyl-ester derivative of the alkaloid apovincamine from Vinca minor leaves. VPN is a selective inhibitor of phosphodiesterase type 1 (PDE1) that has potential neurological effects through inhibition of voltage-gated sodium channel and reduction of neuronal calcium influx. VPN has noteworthy antioxidant, anti-inflammatory, and anti-apoptotic effects with inhibitory effect on glial and astrocyte cells during and following ischemic stroke (IS). VPN is effective as adjuvant therapy in the management of epilepsy; it reduces seizure frequency by 50% in a dose of 2 mg/kg/day. VPN improves psychomotor performances through modulation of brain monoamine pathway mainly on dopamine and serotonin, which play an integral role in attenuation of depressive symptoms. VPN recover cognitive functions and spatial memory through inhibition of hippocampal and cortical PDE1 with augmentation of cyclic adenosin monophosphate and cyclic guanosin monophosphate ratio, enhancement of cholinergic neurotransmission, and inhibition of neuronal inflammatory mediators. Therefore, VPN is an effective agent in the management of IS and plays an integral role in the prevention and attenuation of poststroke epilepsy, depression, and cognitive deficit through direct cAMP/cGMP-dependent pathway or indirectly through anti-inflammatory and antioxidant effects.

Blood glutamate scavenging as a novel glutamate-based therapeutic approach for post-stroke depression

Post-stroke depression (PSD) is a major complication of stroke that significantly impacts functional recovery and quality of life. While the exact mechanism of PSD is unknown, recent attention has focused on the association of the glutamatergic system in its etiology and treatment. Minimizing secondary brain damage and neuropsychiatric consequences associated with excess glutamate concentrations is a vital part of stroke management. The blood glutamate scavengers, oxaloacetate and pyruvate, degrade glutamate in the blood to its inactive metabolite, 2-ketoglutarate, by the coenzymes glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT), respectively. This reduction in blood glutamate concentrations leads to a subsequent shift of glutamate down its concentration gradient from the blood to the brain, thereby decreasing brain glutamate levels. Although there are not yet any human trials that support blood glutamate scavengers for clinical use, there is increasing evidence from animal research of their efficacy as a promising new therapeutic approach for PSD. In this review, we present recent evidence in the literature of the potential therapeutic benefits of blood glutamate scavengers for reducing PSD and other related neuropsychiatric conditions. The evidence reviewed here should be useful in guiding future clinical trials.

Minocycline treatment prevents depression and anxiety-like behaviors and promotes neuroprotection after experimental ischemic stroke

Depression and anxiety have been reported as the major neuropsychiatric consequences following stroke. Minocycline, a neuroprotective drug has minimized depressive symptoms in patients with major depressive disorders and anxiety-like symptoms. In addition, minocycline demonstrated efficacy and seemed a promising neuroprotective agent in acute stroke patients. The present studied evaluated the effects of minocycline treatment on the depression and anxiety-like behaviors, brain damage and expression of inflammatory and neuroprotective mediators after transient global cerebral ischemia in C57BL/6 mice. Brain ischemia was induced by bilateral occlusion of the common carotids (BCCAo) for 25 min and subsequent reperfusion. Sham and BCCAo animals received minocycline at a dose of 30 mg/kg by intraperitoneal injection during 14 days. The locomotor activity, depression and anxiety-like behaviors were assessed by open field, forced swim and elevated plus maze tests, respectively. Then, the brains were removed and processed to evaluate brain damage by histological and morphometric analysis, hippocampal neurodegeneration using Fluoro-Jade C histochemistry, microglial activity using iba-1 immunohistochemistry, brain levels of TNF, IFN-γ, IL-6, IL-10, IL-12p70 and CCL2 by CBA, CX3CL1 and BDNF by ELISA assays. The animals developed depression and anxiety-like behaviors post-stroke and minocycline treatment prevented those neurobehavioral changes. Moreover, minocycline-treated BCCAo animals showed less intense brain damage in the cerebral cortex, brainstem and cerebellum as well as significantly reduced hippocampal neurodegeneration. BCCAo groups exhibited up-regulation of some cytokines at day 14 after ischemia and brain levels of CX3CL1 and BDNF remained unaltered. Our data indicate that the depression and anxiety-like behavioral improvements promoted by minocycline treatment might be related to its neuroprotective effect after brain ischemia in mice.

[Correlations between parameters of central hemodynamics and cytokine profile in chronic kidney disease in combination with cerebrovascular diseases]

AIM

To study the relationship between central hemodynamics and arterial stiffness indicators with cystatin C, tumor necrosis factor-alpha (TNF-alpha) and interleukin-(IL)-10 in patients with chronic kidney disease (CKD) in combination with cerebrovascular diseases (CEV).

MATERIAL AND METHODS

One hundred and twenty patients, aged from 19 to 81 years, with signs of chronic renal dysfunction, including 73 with CKD (1st group) and 47 with CKD in combination with CEH (group 2), were examined. 'AngioScan' (Russia) was used to study indices of arterial rigidity. Blood plasma concentrations of TNF-alpha, IL-10 and cystatin C were determined by the enzyme immunoassay.

RESULTS

There is a significant increase (p<0.05) in the systolic, diastolic, central levels of arterial pressure, augmentation index, the index of increase at a pulse rate of 75 per min, the age index, the age of the vascular system and cystatin C content in the patients with CKD in combination with CEV compared to the patients with CKD without accompanying CEH. In the group of patients with CKD in combination with CEV, a correlation was found between the level of TNF-alpha and arterial stiffness index on one side (r=0.318; p<0.05) and the augmentation index on the other (r=0.299; p<0.05).

CONCLUSION

The results confirm the fact that there is a significant increase in the level of plasma cystatin C and a decrease in GFR in patients with CKD in combination with CEV. Correlations were found between the level of TNF-alpha, augmentation index and deterioration of parameters of central hemodynamics and arterial stiffness in CKD in combination with CEH.

Shared genetic risk factors for depression and stroke

BACKGROUND

The comorbidity of major depressive disorder (MDD) and stroke are common in clinic. There is a growing body of evidence suggesting a bi-directional relationship between stroke and depression. However, the mechanisms underlying the relationship between MDD and stroke are poorly investigated. Considering that both MDD and stroke can be heritable and are influenced by multiple risk genes, shared genetic risk factors between MDD and stroke may exist.

OBJECTIVE

The objective is to review the existing evidence for common genetic risk factors for both MDD and stroke and to outline the possible pathophysiological mechanisms mediating this association.

METHODS

A systematic review and meta-analysis was performed. Gene association studies regarding stroke and depression were searched in the database PubMed, CNKI, and Chinese Biomedical Literature Database before December 2018. Statistical analysis was performed using the software Revman 5.3.

RESULTS

Genetic polymorphisms of 4 genes, methylenetetrahydrofolate reductase (MTHFR) and apolipoprotein E (ApoE) have been demonstrated to associate with the increased risk for both MDD and stroke, while the association between identified polymorphisms in angiotensin converting enzyme (ACE) and serum paraoxonase (PON1) with depression is still under debate, for the existing studies are insufficient in sample size. These results suggest the possible pathophysiological mechanisms that are common to these two disorders, including immune-inflammatory imbalance, increased oxidative and nitrative stress, dysregulation of lipoprotein and lipid metabolism, and changes of cerebrovascular morphology and function. Other associated genes with few or conflicting results have also been included, and a few studies have investigated the effects of the described polymorphisms on MDD and stroke comorbidity, such as post stroke depression.

CONCLUSION

These findings suggest that shared genetic pathways may contribute to the comorbidity of MDD and stroke. Studies to evaluate the shared genetic variations between MDD and stroke may provide insights into the molecular mechanisms that trigger disease progression.

A cross-sectional study to assess the association between major depression and inflammatory markers in patients with acute ischemic stroke

BACKGROUND

Increased interest in the relationship between affective disorder and long-term health consequences has generated recent examinations of depression and stroke. Observations suggest that depressive disorder is associated with abnormal physiological and immunological responses and a resultant increase in inflammatory markers. Given the high prevalence of stroke and associated costs for the community, it is important to understand the mechanisms that may impact on the outcome to achieve the best possible prognosis.

AIMS

The view that inflammatory factors contribute to depression is predicated on findings that circulating cytokines and other inflammatory factors are increased in depressed patients. Therefore, it has been hypothesized that inflammation could be one of the mechanisms by which depression increases risk for ischemic stroke. Our aim was to determine whether there is any relationship between major depression and tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), IL-18, brain-derived neurotrophic factor (BDNF), and neuron-specific enolase (NSE) in patients with acute ischemic stroke (AIS).

STUDY DESIGN

This was as a cross-sectional design.

MATERIALS AND METHODS

This study has a cross-sectional design, and it was conducted in Necmettin Erbakan University, the Meram Faculty of Medicine in Konya, Turkey, between 2014 and 2015. Fifty-three AIS patients admitted to the hospital within the first 24 h after stroke onset were recruited. Major depression was ascertained by means of the structured clinical interview for the diagnostic and statistical manual of mental disorders, Fourth Edition/Clinical Version. The enzyme-linked immunosorbent assay was used to measure the serum levels of TNF-α, IL-1 β, IL-18, BDNF, and NSE at admission.

RESULTS

A total of 53 patients with a mean age of 65.9 years were recruited. Of these patients, 17 (32.1%) had major depression. Depressive and nondepressive patients had similar demographical and clinical features. There was no significant statistical difference between depressive and nondepressive patients with AIS with respect to levels of TNF-α, IL-1 β, IL-18, BDNF, and NSE.

CONCLUSION

This study suggests that in patients who have experienced AIS, there is no significant relationship between major depression and basal proinflammatory cytokines (TNF-α, IL-1 β, IL-18), BDNF, and NSE.

Effect of Inflammation on the Process of Stroke Rehabilitation and Poststroke Depression

A considerable body of evidence has shown that inflammation plays an important role in the process of stroke rehabilitation and development of poststroke depression (PSD). However, the specific molecular and cellular mechanisms involved remain unclear. In this review, we summarize how neuroinflammation affects stroke rehabilitation and PSD. We mainly focus on the immune/inflammatory response, involving astrocytes, microglia, monocyte-derived macrophages, cytokines (tumor necrosis factor alpha, interleukin 1), and microRNAs (microRNA-124, microRNA 133b). This review provides new insights into the effect of inflammation on the process of stroke rehabilitation and PSD and potentially offer new therapeutic targets of stroke and PSD.

Poststroke Depression Biomarkers: A Narrative Review

Poststroke depression (PSD) is the most prevalent psychiatric disorder after stroke, which is independently correlated with negative clinical outcome. The identification of specific biomarkers could help to increase the sensitivity of PSD diagnosis and elucidate its pathophysiological mechanisms. The aim of current study was to review and summarize literature exploring potential biomarkers for PSD diagnosis. The PubMed database was searched for papers published in English from October 1977 to December 2017, 90 of which met inclusion criteria for clinical studies related to PSD biomarkers. PSD biomarkers were subdivided into neuroimaging, molecular, and neurophysiological. Some of them could be recommended to support PSD diagnosing. According to the data, lesions affecting the frontal-subcortical circles of mood regulation (prefrontal cortex, basal nuclei, and thalamus) predominantly in the left hemisphere can be considered as neuroimaging markers and predictors for PSD for at least 1 year after stroke. Additional pontine and lobar cerebral microbleeds in acute stroke patients, as well as severe microvascular lesions of the brain, increase the likelihood of PSD. The following molecular candidates can help to differentiate PSD patients from non-depressed stroke subjects: decreased serum BDNF concentrations; increased early markers of inflammation (high-sensitivity C-reactive protein, ferritin, neopterin, and glutamate), serum pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-18, IFN-γ), as well as pro-inflammatory/anti-inflammatory ratios (TNF-α/IL-10, IL-1β/IL-10, IL-6/IL-10, IL-18/IL-10, IFN-γ/IL-10); lowered complement expression; decreased serum vitamin D levels; hypercortisolemia and blunted cortisol awakening response; S/S 5-HTTLPR, STin2 9/12, and 12/12 genotypes of the serotonin transporter gene SLC6A4, 5-HTR2a 1438 A/A, and BDNF met/met genotypes; higher SLC6A4 promoter and BDNF promoter methylation status. Neurophysiological markers of PSD, that reflect a violation of perception and cognitive processing, are the elongation of the latency of N200, P300, and N400, as well as the decrease in the P300 and N400 amplitude of the event-related potentials. The selected panel of biomarkers may be useful for paraclinical underpinning of PSD diagnosis, clarifying various aspects of its multifactorial pathogenesis, optimizing therapeutic interventions, and assessing treatment effectiveness.

Neuroinflammation and neurotoxicity contribute to neuroprogression in neurological and psychiatric disorders

The immune system and inflammatory processes contribute to brain-related pathologies in most, if not all, neurological and psychiatric disorders. Stress is a key factor in inducing immune system dysregulation in conjunction with genetic, epigenetic and environmental factors. Activation of the immune response can alter neurotransmission leading, among others, to serotonin deficiency, and increased production of neurotoxic substances contributing to disease progression. The concept of neuroprogression is gaining acceptance among clinicians and researches as it seeks to explain the mechanism(s) responsible for disease chronicity, recurrence and treatment resistance. Therefore, measurement of neuroinflammatory biomarkers along with assessment of neurotoxic metabolites, oxidative stress and neuroplasticity impairment, will ultimately be useful tools to predict and possibly prevent the development and progression of neuropsychiatric disorders as well as to identify the most efficacious treatments.

Diversiform Etiologies for Post-stroke Depression

After the onset of stroke, many patients suffer from emotional behavior changes. Approximately, one-third of stroke survivors are affected by post-stroke depression (PSD), making it a serious social and public health problem. Post-stroke depression (PSD) has an important impact on the course, recovery, and prognosis of stroke. The pathogenesis of PSD is very complex, involving many factors such as biological mechanism and social psychological mechanisms. This article provides a brief review of the hot issues related to etiologies of PSD.

Mindfulness mediates the physiological markers of stress: Systematic review and meta-analysis

Meditation is a popular form of stress management, argued to mediate stress reactivity. However, many studies in this field commonly fail to include an active control group. Given the frequency with which people are selecting meditation as a form of self-management, it is important to validate if the practice is effective in mediating stress-reactivity using well-controlled studies. Thus, we aimed to conduct a meta-analysis investigating the neurobiological effects of meditation, including focused attention, open monitoring and automatic self-transcending subtypes, compared to an active control, on markers of stress. In the current meta-analysis and systematic review, we included randomised controlled trials comparing meditation interventions compared to an active control on physiological markers of stress. Studied outcomes include cortisol, blood pressure, heart-rate, lipids and peripheral cytokine expression. Forty-five studies were included. All meditation subtypes reduced systolic blood pressure. Focused attention meditations also reduced cortisol and open monitoring meditations also reduced heart rate. When all meditation forms were analysed together, meditation reduced cortisol, C - reactive protein, blood pressure, heart rate, triglycerides and tumour necrosis factor-alpha. Overall, meditation practice leads to decreased physiological markers of stress in a range of populations.

Diabetes mellitus is associated with late-onset post-stroke depression

OBJECTIVE

To explore the associated factors of late-onset post-stroke depression (PSD).

METHODS

A total of 251 patients with acute ischemic stroke were recruited. The evaluation of depression was performed 2 weeks after ischemia. 206 patients showing no depression in 2 weeks were followed up. They were divided into late-onset PSD group and non-depressed group by clinical interview with Hamilton depression scale score 3 months after stroke. On the first day following hospitalization, the clinical data including age, gender, educational level and vascular risk factors were recorded. The severity, etiological subtype and location of stroke were evaluated. The inflammatory mediators, glucose and lipid levels were recorded on the day of admission. The association between clinical factors and late-onset PSD was explored by logistic regression analysis. The ROC analysis was performed to evaluate the predicting power of the clinical factors.

RESULTS

187 of 206 patients completed the assessment 3 months after stroke. 19 (10.16%) patients were diagnosed as late onset PSD. Diabetes mellitus was an independent risk factor for late-onset PSD (OR 2.675, p = 0.047). ROC analysis demonstrated that glucose and HbA1C could predict late-onset PSD with specificity of 84.4%.

LIMITATIONS

The sample of our study was small. The results should be further confirmed in a larger cohort of patients with acute ischemic stroke.

CONCLUSIONS

The acute ischemic stroke patients with diabetes mellitus were more tendered to suffer late-onset PSD.

Inflammation and the Silent Sequelae of Stroke

Depression and fatigue are common after stroke and negatively impact the quality of life of stroke survivors. The biological bases of these symptoms are unknown, but an abundance of data point to a role for inflammation. This review highlights evidence supporting the contribution of inflammation to poststroke depression and poststroke fatigue. Potential treatments for poststroke depression and poststroke fatigue are explored, with a special emphasis on those that modulate the immune response.

Effects of IL1B single nucleotide polymorphisms on depressive and anxiety symptoms are determined by severity and type of life stress

Interleukin-1β is one of the main mediators in the cross-talk between the immune system and the central nervous system. Higher interleukin-1β levels are found in mood spectrum disorders, and the stress-induced expression rate of the interleukin-1β gene (IL1B) is altered by polymorphisms in the region. Therefore we examined the effects of rs16944 and rs1143643 single nucleotide polymorphisms (SNPs) within the IL1B gene on depressive and anxiety symptoms, as measured by the Brief Symptom Inventory, in a Hungarian population sample of 1053 persons. Distal and proximal environmental stress factors were also included in our analysis, namely childhood adversity and recent negative life-events. We found that rs16944 minor (A) allele specifically interacted with childhood adversity increasing depressive and anxiety symptoms, while rs1143643's minor (A) allele showed protective effect against depressive symptoms after recent life stress. The genetic main effects of the two SNPs were not significant in the main analysis, but the interaction effects remained significant after correction for multiple testing. In addition, the effect of rs16944 A allele was reversed in a subsample with low-exposure to life stress, suggesting a protective effect against depressive symptoms, in the post hoc analysis. In summary, both of the two IL1B SNPs showed specific environmental stressor-dependent effects on mood disorder symptoms. We also demonstrated that the presence of exposure to childhood adversity changed the direction of the rs16944 effect on depression phenotype. Therefore our results suggest that it is advisable to include environmental factors in genetic association studies when examining the effect of the IL1B gene.

Microglial dysfunction connects depression and Alzheimer's disease

Alzheimer's disease (AD) and major depressive disorder (MDD) are highly prevalent neuropsychiatric conditions with intriguing epidemiological overlaps. Depressed patients are at increased risk of developing late-onset AD, and around one in four AD patients are co-diagnosed with MDD. Microglia are the main cellular effectors of innate immunity in the brain, and their activation is central to neuroinflammation - a ubiquitous process in brain pathology, thought to be a causal factor of both AD and MDD. Microglia serve several physiological functions, including roles in synaptic plasticity and neurogenesis, which may be disrupted in neuroinflammation. Following early work on the 'sickness behavior' of humans and other animals, microglia-derived inflammatory cytokines have been shown to produce depressive-like symptoms when administered exogenously or released in response to infection. MDD patients consistently show increased circulating levels of pro-inflammatory cytokines, and anti-inflammatory drugs show promise for treating depression. Activated microglia are abundant in the AD brain, and concentrate around senile plaques, hallmark lesions composed of aggregated amyloid-β peptide (Aβ). The Aβ burden in affected brains is regulated largely by microglial clearance, and the complex activation state of microglia may be crucial for AD progression. Intriguingly, recent reports have linked soluble Aβ oligomers, toxins that accumulate in AD brains and are thought to cause memory impairment, to increased brain cytokine production and depressive-like behavior in mice. Here, we review recent findings supporting the inflammatory hypotheses of AD and MDD, focusing on microglia as a common player and therapeutic target linking these devastating disorders.

A Pathway Proteomic Profile of Ischemic Stroke Survivors Reveals Innate Immune Dysfunction in Association with Mild Symptoms of Depression - A Pilot Study

Depression after stroke is a common occurrence, raising questions as to whether depression could be a long-term biological and immunological sequela of stroke. Early explanations for post-stroke depression (PSD) focused on the neuropsychological/psychosocial effects of stroke on mobility and quality of life. However, recent investigations have revealed imbalances of inflammatory cytokine levels in association with PSD, though to date, there is only one published proteomic pathway analysis testing this hypothesis. Thus, we examined the serum proteome of stroke patients (n = 44, mean age = 63.62 years) and correlated these with the Montgomery–Åsberg Depression Rating Scale (MADRS) scores at 3 months post-stroke. Overall, the patients presented with mild depression symptoms on the MADRS, M = 6.40 (SD = 7.42). A discovery approach utilizing label-free relative quantification was employed utilizing an LC-ESI–MS/MS coupled to a LTQ-Orbitrap Elite (Thermo-Scientific). Identified peptides were analyzed using the gene set enrichment approach on several different genomic databases that all indicated significant downregulation of the complement and coagulation systems with increasing MADRS scores. Complement and coagulation systems are traditionally thought to play a key role in the innate immune system and are established precursors to the adaptive immune system through pro-inflammatory cytokine signaling. Both systems are known to be globally affected after ischemic or hemorrhagic stroke. Thus, our results suggest that lowered complement expression in the periphery in conjunction with depressive symptoms post-stroke may be a biomarker for incomplete recovery of brain metabolic needs, homeostasis, and inflammation following ischemic stroke damage. Further proteomic investigations are now required to construct the temporal profile, leading from acute lesion damage to manifestation of depressive symptoms. Overall, the findings provide support for the involvement of inflammatory and immune mechanisms in PSD symptoms and further demonstrate the value and feasibility of the proteomic approach in stroke research.

Clinical predictor and circulating microRNA profile expression in patients with early onset post-stroke depression

OBJECTIVE

We aim to explore the clinical factors and blood biomarker for predicting the early-onset post-stroke depression (PSD).

METHODS

251 acute ischemic stroke patients were divided into PSD group and non-PSD group by Hamilton depression scale in 2 weeks after stroke. The clinical data, the severity, etiology and location of stroke were recorded. The analysis of inflammatory mediator, glycose and lipid metabolism was performed on the day of admission. The association between clinical factors and early onset PSD was studied by logistic regression analysis. In addition, the differentially expressed miRNAs in plasma between the two groups were screened by gene chip and the bio-information was further investigated by GO and KEEG analysis.

RESULTS

Among 251 patients, 45 (17.93%) were diagnosed as early onset PSD. NIHSS score (>3) and carotid stenosis were independent relative factors with early-onset PSD (OR 3.479 and 2.617, p=0.000 and 0.009, respectively). Moreover, lower LDL trended toward association with early onset PSD in minor stroke subgroup (p=0.084). MiRNA profile demonstrated 25 differential expressed circulating miRNAs with FC≥2 and P≤0.05 between the two groups. The target genes of these miRNAs were enriched in pathways of cancer and MAPK signaling.

LIMITATIONS

The sample of the study was small. The results should be further confirmed in large cohort patients.

CONCLUSIONS

Early onset PSD was more likely in patients with severe neurological deficits and carotid artery stenosis, also note the possible association between lower LDL and depression in minor stroke. Blood miRNAs may be served as a potential biomarker for PSD diagnosis.

Ischemic, traumatic and neurodegenerative brain inflammatory changes

This review serves to link the role of the immune system in the neuropathology of acute ischemic stroke, traumatic brain injury and neurodegenerative disease. The blood–brain barrier delineates the CNS from the peripheral immune system. However, the blood–cerebrospinal fluid barrier acts as a gate between the periphery and the brain, permitting immune activity crosstalk and modulation. In acute ischemic stroke, traumatic brain injury and other neurodegenerative diseases, the blood–brain barrier is compromised and an influx of inflammatory cells and plasma proteins occurs, resulting in edema, demyelination, cell dysfunction and death, and neurobehavioral changes. The role of the complement system, key cytokines, microglia and other neuroglia in brain degenerative pathology will be discussed.

Depression--a common disorder across a broad spectrum of neurological conditions: a cross-sectional nationally representative survey

OBJECTIVE

To estimate the prevalence of depression across a range of neurological conditions in a nationally representative sample.

METHODS

The data source was the Survey of Living with Neurological Conditions in Canada (SLNCC), which accrued its sample by selecting participants from the Canadian Community Health Survey. The point prevalence of depression was estimated by assessment of depressive symptoms with the Patient Health Questionnaire, Brief (Patient Health Questionnaire, 9-item).

RESULTS

A total of n=4408 participated in the SLNCC. The highest point prevalence of depression (>30%) was seen in those with traumatic brain injury and brain/spinal cord tumors. Depression was also highly prevalent (18-28%) in those with (listed from highest to lowest) Alzheimer's disease/dementia, dystonia, multiple sclerosis, Parkinson's disease, stroke, migraine, epilepsy and spina bifida. The odds ratios for depression, with the referent group being the general population, were significant (from highest to lowest) for migraine, traumatic brain injury, stroke, dystonia and epilepsy.

CONCLUSIONS

All neurological conditions included in this study are associated with an elevated prevalence of depression in community populations. The conditions with the highest prevalence are traumatic brain injury and brain/spinal cord tumors.

A systematic review of randomised control trials on the effects of yoga on stress measures and mood

Stress related disorders such as depression and anxiety are leading sources of disability worldwide, and current treatment methods such as conventional antidepressant medications are not beneficial for all individuals. There is evidence that yoga has mood-enhancing properties possibly related to its inhibitory effects on physiological stress and inflammation, which are frequently associated with affective disorders. However the biological mechanisms via which yoga exerts its therapeutic mood-modulating effects are largely unknown. This systematic review investigates the effects of yoga on sympathetic nervous system and hypothalamic pituitary adrenal axis regulation measures. It focuses on studies collecting physiological parameters such as blood pressure, heart rate, cortisol, peripheral cytokine expression and/or structural and functional brain measures in regions involved in stress and mood regulation. Overall the 25 randomised control studies discussed provide preliminary evidence to suggest that yoga practice leads to better regulation of the sympathetic nervous system and hypothalamic-pituitary-adrenal system, as well as a decrease in depressive and anxious symptoms in a range of populations. Further research is warranted to confirm these preliminary findings and facilitate implementation in clinical settings.

Neurological disorders, depression and inflammation: is there a common link?

To understand the origin of co-morbidity between neurological disorders and depressive illness, a multifactorial model is in order. Diverse approaches have been undertaken to elucidate the co-morbidity. Of these, the concept that inflammatory processes contribute to brain-related pathologies has been gaining traction. Inflammatory processes have been identified in most, if not all, neurological conditions. Similarly, major depressive disorder has been associated with a chronic proinflammatory status. Activation of the immune response can alter neurotransmission leading, among others, to serotonin deficiency, and increased production of neurotoxic substances contributing to primary disease progression. Therefore, inflammatory factors might serve as biomarkers to predict and ultimately prevent the development and progression of neuropsychiatric disorders as well as to identify the most efficacious treatments.

Stroke and depression: A bidirectional link

A number of studies have assessed the influence of depression on the risk of cardiovascular disease. A growing literature indicates a link between depression and cerebrovascular events, although the direction of this association remains unclear. Numerous data have emerged suggesting an association between depressive symptoms and subsequent risk of stroke, thus leading to the hypothesis that a direct causality between depression and stroke exists. Notwithstanding, how depression may act as a risk factor for stroke is still unclear. Depression might be linked to stroke via neuroendocrine and inflammation effects, through correlation with major comorbidities such as hypertension and diabetes or by intervention of lifestyle behavioral mediators. Finally, antidepressant medications have recently drawn attention for a possible association with increased risk of stroke, although such findings remain uncertain. Depression has been also established as an important consequence after stroke, exerting a significant adverse impact on the course of motor recovery, social functioning and, overall, on quality of life. Post stroke depression occurs in nearly one third of stroke cases, but the exact mechanism leading to depression after stroke is still incompletely understood. In this article, we will review contemporary epidemiologic studies, discuss potential mechanisms and specific aspects of the complex relation between depression and stroke.

The neurobiological pathogenesis of poststroke depression

Poststroke depression (PSD) is an important consequence after stroke, with negative impact on stroke outcome. The pathogenesis of PSD is complicated, with some special neurobiological mechanism, which mainly involves neuroanatomical, neuron, and biochemical factors and neurogenesis which interact in complex ways. Abundant studies suggested that large lesions in critical areas such as left frontal lobe and basal ganglia or accumulation of silent cerebral lesions might interrupt the pathways of monoamines or relevant pathways of mood control, thus leading to depression. Activation of immune system after stroke produces more cytokines which increase glutamate excitotoxicity, results in more cell deaths of critical areas and enlargement of infarctions, and, together with hypercortisolism induced by stress or inflammation after stroke which could decrease intracellular serotonin transporters, might be the key biochemical change of PSD. The interaction among cytokines, glucocorticoid, and neurotrophin results in the decrease of hippocampal neurogenesis which has been proved to be important for mood control and pharmaceutical effect of selective serotonin reuptake inhibitors and might be another promising pathway to understand the pathogenesis of PSD. In order to reduce the prevalence of PSD and improve the outcome of stroke, more relevant studies are still required to clarify the pathogenesis of PSD.

Omega-3 supplementation improves cognition and modifies brain activation in young adults

OBJECTIVE

The current study aimed to investigate the effects of eicosapentaenoic acid (EPA)-rich and docosahexaenoic acid (DHA)-rich supplementations on cognitive performance and functional brain activation.

DESIGN

A double-blind, counterbalanced, crossover design, with a 30-day washout period between two supplementation periods (EPA-rich and DHA-rich) was employed. Functional magnetic resonance imaging scans were obtained during performance of Stroop and Spatial Working Memory tasks prior to supplementation and after each 30-day supplementation period.

RESULTS

Both supplementations resulted in reduced ratio of arachidonic acid to EPA levels. Following the EPA-rich supplementation, there was a reduction in functional activation in the left anterior cingulate cortex and an increase in activation in the right precentral gyrus coupled with a reduction in reaction times on the colour-word Stroop task. By contrast, the DHA-rich supplementation led to a significant increase in functional activation in the right precentral gyrus during the Stroop and Spatial Working Memory tasks, but there was no change in behavioural performance.

CONCLUSIONS

By extending the theory of neural efficiency to the within-subject neurocognitive effects of supplementation, we concluded that following the EPA-rich supplementation, participants' brains worked 'less hard' and achieved a better cognitive performance than prior to supplementation. Conversely, the increase in functional activation and lack of improvement in time or accuracy of cognitive performance following DHA-rich supplementation may indicate that DHA-rich supplementation is less effective than EPA-rich supplementation in enhancing neurocognitive functioning after a 30-day supplementation period in the same group of individuals.

STroke imAging pRevention and Treatment (START): A Longitudinal Stroke Cohort Study: Clinical Trials Protocol

Rationale

Stroke and poststroke depression are common and have a profound and ongoing impact on an individual's quality of life. However, reliable biological correlates of poststroke depression and functional outcome have not been well established in humans.

Aims

Our aim is to identify biological factors, molecular and imaging, associated with poststroke depression and recovery that may be used to guide more targeted interventions.

Design

In a longitudinal cohort study of 200 stroke survivors, the START – STroke imAging pRevention and Treatment cohort, we will examine the relationship between gene expression, regulator proteins, depression, and functional outcome. Stroke survivors will be investigated at baseline, 24 h, three-days, three-months, and 12 months poststroke for blood-based biological associates and at days 3–7, three-months, and 12 months for depression and functional outcomes. A sub-group ( n = 100), the PrePARE: Prediction and Prevention to Achieve optimal Recovery Endpoints after stroke cohort, will also be investigated for functional and structural changes in putative depression-related brain networks and for additional cognition and activity participation outcomes. Stroke severity, diet, and lifestyle factors that may influence depression will be monitored. The impact of depression on stroke outcomes and participation in previous life activities will be quantified.

Study Outcomes

Clinical significance lies in the identification of biological factors associated with functional outcome to guide prevention and inform personalized and targeted treatments. Evidence of associations between depression, gene expression and regulator proteins, functional and structural brain changes, lifestyle and functional outcome will provide new insights for mechanism-based models of poststroke depression.

Initiation of statin therapy after acute myocardial infarction is not associated with worsening depressive symptoms: insights from the Prospective Registry Evaluating Outcomes After Myocardial Infarctions: Events and Recovery (PREMIER) and Translational Research Investigating Underlying Disparities in Acute Myocardial Infarction Patients' Health Status (TRIUMPH) registries

BACKGROUND

Whereas statins are considered the cornerstone of prevention after acute myocardial infarction (AMI), concerns about worsening depression in association with their use have been raised.

METHODS

Using data from 2 prospective AMI registries (PREMIER and TRIUMPH), we examined the change in depressive symptoms from baseline and at 1, 6 and 12 months among statin-naïve patients who were and were not discharged on a statin. Depressive symptoms were assessed with the 8-item Patient Health Questionnaire (PHQ-8). Within-group change in PHQ-8 scores from baseline to each follow-up period was assessed using paired t tests. A repeated-measures propensity-matched analysis examined whether changes in PHQ-8 scores from baseline were different between statin-treated and statin-untreated patients.

RESULTS

Of 3,675 patients not previously treated with statins, 3,050 (83%) were discharged on a statin and 625 (17%) were not. Scores of PHQ-8 in the statin group decreased from baseline by a mean (± SD) of 0.9 (± 5.1), 1.2 (± 5), and 1.1 (± 5.1) at 1, 6, and 12 months, respectively. Corresponding changes in the nonstatin group were 0.9 (± 5.2), 1.3 (± 5.1), and 1.5 (± 5.8), respectively (P < .0001 for all comparisons). After propensity matching, 451 patients not discharged on statins with 1,240 patients discharged on statins, the mean change in PHQ-8 scores between baseline and the 3 follow-up time points was not significantly different between groups (mean between-group difference at 1 month: -0.13, 95% CI [-0.69 to 0.43], P = .65; at 6 months: -0.07, 95% CI [-0.66 to 0.52], P = .82; and at 12 months: -0.05, 95% CI [-0.67 to 0.58], P = .88).

CONCLUSIONS

Initiation of statins after AMI was not associated with worsening depression.

CRP, IL-6 and depression: a systematic review and meta-analysis of longitudinal studies

BACKGROUND

Inflammatory markers are raised in cross-sectional studies of depressed patients and may represent an important mediating factor for behaviour, neural plasticity and brain structure.

METHODS

We undertook a systematic review of longitudinal studies, investigating whether raised inflammatory markers indicate an increased risk of subsequent depressive symptoms. We searched three databases (1970-2012) for longitudinal studies with repeat data on CRP or IL-6 levels and subsequent depressive symptoms. We calculated effect sizes using a mixed-effects model, with separate meta-analyses for inflammatory markers and age groups.

RESULTS

We identified eight papers for CRP (14,832 participants) and three for IL-6 (3695 participants). There was a significant association between increased CRP and depressive symptoms (weighted-mean effect size 'unadjusted r'=0.069, p<0.0005; 'adjusted r'=0.046, p<0.0005), with moderate heterogeneity between studies (Q=11.21, p=0.08, I(2)=46.5). For IL-6 the weighted-mean effect size was smaller ('unadjusted r'=0.045, p-value=0.007; 'adjusted r'=0.097, p-value=0.06).

LIMITATIONS

The meta-analysis was based on a relatively small number of studies (particularly for IL-6) and only two inflammatory markers. There was moderate heterogeneity between studies and some evidence of publication bias.

CONCLUSIONS

Raised inflammatory markers have a small but significant association with the subsequent development of depressive symptoms. This is a robust effect which remains significant after adjustment for age and a wide range of factors associated with risk for depression. Our results support the hypothesis that there is a causal pathway from inflammation to depression.

The role of inflammatory cytokines on the aetiopathogenesis of depression

OBJECTIVE

The primary focus of this review is to provide an overview of the role of inflammation in the development of depression. The article will describe how inflammatory cytokines contribute to depression via action on three major pathways in the brain: the neuroendocrine; neurotransmitter depletion; and neuroprogression pathways.

METHODS

An online literature search was carried out in July 2012. Original articles and reviews were selected if they discussed the role of inflammation on the development of depression.

RESULTS

There is a large body of current research on the role of inflammatory cytokines on the development of depression. Cytokines have been found to interact with different pathways in the brain, and may contribute to the development of depression. Cytokines cause hypercortisolaemia by dysregulation of the hypothalamic-pituitary-adrenal axis directly by activating it and indirectly by modifying glucocorticoid receptor sensitivity to cortisol leading to cortisol hypersecretion. Cytokines deplete central synaptic serotonin levels by reducing its synthesis and increasing its reuptake. They may also deplete neurotrophic factors which are believed to play a neuroprotective role against depression. Cytokines activate cellular cascades that cause excitotoxicity and apoptosis and inhibit neurogenesis in the hippocampus.

CONCLUSION

There is a growing body of correlative studies that suggest inflammatory cytokines may be a central factor that can affect multiple neuronal pathways and have an additive effect on the development of depression. However, the fact that not all people with inflammatory conditions suffer from depression suggests that depression is not purely a result of elevated inflammatory cytokines. Depression may be a result of a complex pathology that remains an area of growing interest and importance.