Cytokine changes in the pathophysiology of poststroke depression

Gut microbiota is necessary for pair-housing to protect against post-stroke depression in mice

The goal of this study is to investigate the role of microbiota-gut-brain axis involved in the protective effect of pair-housing on post-stroke depression (PSD). PSD model was induced by occluding the middle cerebral artery (MCAO) plus restraint stress for four weeks. At three days after MCAO, the mice were restrained 2 h per day. For pair-housing (PH), each mouse was pair housed with a healthy isosexual cohabitor for four weeks. While in the other PH group, their drinking water was replaced with antibiotic water. On day 35 to day 40, anxiety- and depression-like behaviors (sucrose consumption, open field test, forced swim test, and tail-suspension test) were conducted. Results showed pair-housed mice had better performance on anxiety- and depression-like behaviors than the PSD mice, and the richness and diversity of intestinal flora were also improved. However, drinking antibiotic water reversed the effects of pair-housing. Furthermore, pair-housing had an obvious improvement in gut barrier disorder and inflammation caused by PSD. Particularly, they showed significant decreases in CD8 lymphocytes and mRNA levels of pro-inflammatory cytokines (TNF-a, IL-1β and IL-6), while IL-10 mRNA was upregulated. In addition, pair-housing significantly reduced activated microglia and increased Nissl's body in the hippocampus of PSD mice. However, all these improvements were worse in the pair-housed mice administrated with antibiotic water. We conclude that pair-housing significantly improves PSD in association with enhanced functions of microbiota-gut-brain axis, and homeostasis of gut microbiota is indispensable for the protective effect of pair-housing on PSD.

Biosensors for psychiatric biomarkers in mental health monitoring

Psychiatric disorders are associated with serve disturbances in cognition, emotional control, and/or behavior regulation, yet few routine clinical tools are available for the real-time evaluation and early-stage diagnosis of mental health. Abnormal levels of relevant biomarkers may imply biological, neurological, and developmental dysfunctions of psychiatric patients. Exploring biosensors that can provide rapid, in-situ, and real-time monitoring of psychiatric biomarkers is therefore vital for prevention, diagnosis, treatment, and prognosis of mental disorders. Recently, psychiatric biosensors with high sensitivity, selectivity, and reproducibility have been widely developed, which are mainly based on electrochemical and optical sensing technologies. This review presented psychiatric disorders with high morbidity, disability, and mortality, followed by describing pathophysiology in a biomarker-implying manner. The latest biosensors developed for the detection of representative psychiatric biomarkers (e.g., cortisol, dopamine, and serotonin) were comprehensively summarized and compared in their sensitivities, sensing technologies, applicable biological platforms, and integrative readouts. These well-developed biosensors are promising for facilitating the clinical utility and commercialization of point-of-care diagnostics. It is anticipated that mental healthcare could be gradually improved in multiple perspectives, ranging from innovations in psychiatric biosensors in terms of biometric elements, transducing principles, and flexible readouts, to the construction of 'Big-Data' networks utilized for sharing intractable psychiatric indicators and cases.

Circulating interleukins concentrations and post-stroke depression: A systematic review and meta-analysis

Interleukins may play a role in supporting the diagnosis of post-stroke depression (PSD). Here, eight databases were employed to search for studies on circulating interleukins concentrations in patients with PSD. A total of 45 studies exploring circulating interleukins in PSD and stroke patients without depression (NPSD) were included in the retrieval database, including IL-1(5), IL-1β (10), IL-2(6), IL-6(35), IL-10(7), IL-17(5), IL-18(6). Then, the RevMan 5.4 software was used for meta-analysis. The results of the meta-analysis showed that the PSD patients have higher concentrations of IL-1, IL-4, IL-6, and lower concentrations of IL-10 than NPSD patients. Additionally, the circulating IL-1, IL-6, and IL-18 concentrations in PSD patients were significantly higher than those in NPSD patients in the acute phase; the circulating IL-6 and IL-17 concentrations in PSD patients were significantly higher than those in NPSD patients at discharge; the PSD patients have lower concentrations sin IL-2 but higher concentrations in IL-6 and IL-17 than NPSD patients at the 3rd and 6th month. Our research provides evidence that circulating interleukins may have clinical utility as a biomarker for identifying 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.

Neuroinflammation and Post-Stroke Depression: Focus on the Microglia and Astrocytes

Post-stroke depression (PSD), a frequent and disabling complication of stroke, has a strong impact on almost thirty percent of stroke survivors. The pathogenesis of PSD is not completely clear so far. Neuroinflammation following stroke is one of underlying mechanisms that involves in the pathophysiology of PSD and plays an important function in the development of depression and is regarded as a sign of depression. During the neuroinflammation after ischemic stroke onset, both astrocytes and microglia undergo a series of morphological and functional changes and play pro-inflammatory or anti-inflammatory effect in the pathological process of stroke. Importantly, astrocytes and microglia exert dual roles in the pathological process of PSD due to the phenotypic transformation. We summarize the latest evidence of neuroinflammation involving in PSD in this review, focus on the phenotypic transformation of microglia and astrocytes following ischemic stroke and reveal the dual roles of both microglia and astrocytes in the PSD via modulating the neuroinflammation.

The predictive role of early inflammation and oxidative stress and the dynamics of cytokines networks in post-stroke depression

BACKGROUNDS

Chronic inflammation and oxidative stress play an important role in the pathogenesis of PSD. The main purposes of this study were to examine the dynamic changes of cytokines networks in PSD and the predictive role of early inflammation and oxidative stress for 2-week PSD.

METHODS

Patients with ischemic stroke were recruited on day 3, and those with Hamilton Depression Rating Scale 24-Item (HAMD-24) ≥8 were classified as ischemic stroke patients with depressive symptoms and others as ischemic stroke patients without depressive symptoms. Subjects were then followed up at 2 weeks and 3 months, with those meeting diagnostic criteria for depressive symptoms on the HAMD ≥8 and the Statistical Manual of Mental Disorders-V (DSM-V) as the PSD group, and the others as the non-PSD group.

RESULTS

At 3 days, IFN-γ, IL-12(p70), IL-12(p40), IL-2, IL-28A/IFNλ2, and IL-19 were elevated in ischemic stroke patients with depressive symptoms. At 2 weeks, IL-12(p40), IL-19, IL-22, IFN-β and MMP-1 all were increased in PSD patients. At 3 months, IL-2, IFN-β and sCD163 increased in PSD group. Longitudinally, the inflammatory response decreased significantly in PSD group from 2 weeks to 3 months of follow-up, while it gradually decreased in non-PSD group from 3 days to 3 months of follow-up. SOD was positively related to IL-12(p70), IFN-γ and IL-20. Plasma IFN-γ at 3 days may be a potential predictive biomarker for 2-week PSD.

CONCLUSIONS

Peripheral inflammation and oxidative stress are involved in the pathogenesis of PSD, providing new insights for its diagnosis and treatment.

Investigating the Potential Mechanisms and Therapeutic Targets of Inflammatory Cytokines in Post-stroke Depression

Post-stroke depression (PSD) affects approximately one-third of stroke survivors, severely impacting general recovery and quality of life. Despite extensive studies, the exact mechanisms underlying PSD remain elusive. However, emerging evidence implicates proinflammatory cytokines, including interleukin-1β, interleukin-6, tumor necrosis factor-alpha, and interleukin-18, play critical roles in PSD development. These cytokines contribute to PSD through various mechanisms, including hypothalamic-pituitary-adrenal (HPA) axis dysfunction, neurotransmitter alterations, neurotrophic factor changes, gut microbiota imbalances, and genetic predispositions. This review is aimed at exploring the role of cytokines in stroke and PSD while identifying their potential as specific therapeutic targets for managing PSD. A more profound understanding of the mechanisms regulating inflammatory cytokine expression and anti-inflammatory cytokines like interleukin-10 in PSD may facilitate the development of innovative interventions to improve outcomes for stroke survivors experiencing depression.

Time-dependent dual effect of microglia in ischemic stroke

Stroke, the third leading cause of death and disability worldwide, is classified into ischemic or hemorrhagic, in which approximately 85% of strokes are ischemic. Ischemic stroke occurs as a result of arterial occlusion due to embolus or thrombus, with ischemia in the perfusion territory supplied by the occluded artery. The traditional concept that ischemic stroke is solely a vascular occlusion disorder has been expanded to include the dynamic interaction between microglia, astrocytes, neurons, vascular cells, and matrix components forming the "neurovascular unit." Acute ischemic stroke triggers a wide spectrum of neurovascular disturbances, glial activation, and secondary neuroinflammation that promotes further injury, ultimately resulting in neuronal death. Microglia, as the resident macrophages in the central nervous system, is one of the first responders to ischemic injury and plays a significant role in post-ischemic neuroinflammation. In this review, we reviewed the mechanisms of microglia in multiple stages of post-ischemic neuroinflammation development, including acute, sub-acute and chronic phases of stroke. A comprehensive understanding of the dynamic variation and the time-dependent role of microglia in post-stroke neuroinflammation could aid in the search for more effective therapeutics and diagnostic strategies for ischemic stroke.

Physio-psycho-social interaction mechanism in dyadic health of young and middle-aged stroke survivors and their spousal caregivers: a longitudinal observational study protocol

INTRODUCTION

In recent years, stroke has become more common among young people. Stroke not only has a profound impact on patients' health but also incurs stress and health threats to their caregivers, especially spousal caregivers. Moreover, the health of stroke survivors and their caregivers is interdependent. To our knowledge, no study has explored dyadic health of young and middle-aged stroke survivors and their spousal caregivers from physiological, psychological and social perspectives. Therefore, this proposed study aims to explore the mechanism of how physiological, psychological and social factors affect dyadic health of young and middle-aged stroke survivors and their spousal caregivers. The findings of this study will provide implications for developing interventions to improve dyadic health of this growing population.

METHODS AND ANALYSES

We will collect data from 57 dyads of young and middle-aged stroke survivors and their spousal caregivers during hospitalisation and at 1, 3, 6, 9 and 12 months after discharge. Questionnaires will be used to collect participants' demographic information, stress, depression, anxiety, benefit finding, social support, mutuality and quality of life. The following physiological reactions will be collected at baseline, including interleukin 6, tumour necrosis factor-alpha and salivary cortisol.

ETHICS AND DISSEMINATION

The study was approved by the ethics review committee of life sciences of Zhengzhou University (No. ZZUIRB2020-53). Prior to being enrolled in the study, participants will be given full and detailed information about the possible risks involved, the informed consent process, confidentiality, the study procedure and secure data storage. Participants will be guaranteed that they can withdraw from the study at any time without providing a reason or leading to any consequences. Both oral and written informed consent will be obtained from all participants. The findings of this proposed study will be disseminated through peer-reviewed journals and academic conferences.

Elevated red blood cell distribution width levels predict depression after intracerebral hemorrhage: A 3-month follow-up study

Objectives

Inflammation vitally impacts the progression of depression resulting from intracerebral hemorrhage (ICH), while red blood cell distribution width (RDW) marks inflammatory-related diseases. The present study aimed at evaluating how RDW affects depression after ICH.

Methods

From prospective analyses of patients admitted to our department between January 2017 and September 2022, ICH patients with complete medical records were evaluated. The 17-item Hamilton Depression (HAMD-17) scale was used for measuring the depressive symptoms at 3 months after ICH. Diagnosis of post-ICH depression was conducted for patients based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V) criteria.

Results

A total of 438 patients were enrolled in the study, out of which 93 (21.23%) patients had PSD at the 3-month follow-up. Accordingly, patients with depression had higher RDW levels (13.70 [IQR: 13.56–13.89] vs.13.45 [IQR: 12.64–13.75], p &lt; 0.001) at admission compared with those without depression. In multivariate analyses, RDW was used for independently predicting the depression after ICH at 3 months (OR: 2.832 [95% CI: 1.748–4.587], p &lt; 0.001). After adjusting the underlying confounding factors, the odds ratio (OR) of depression after ICH was 4.225 (95% CI: 1.686–10.586, p = 0.002) for the highest tertile of RDW relative to the lowest tertile. With an AUC of 0.703 (95% CI: 0.649–0.757), RDW demonstrated a significantly better discriminatory ability relative to CRP and WBC. RDW as an indicator for predicting depression after ICH had an optimal cutoff value of 13.68, and the sensitivity and specificity were 63.4% and 64.6%, respectively.

Conclusions

Elevated RDW level predicted post-ICH depression at 3 months, confirming RDW as an effective inflammatory marker for predicting depression after ICH.

The role of indoleamine 2,3-dioxygenase 1 in early-onset post-stroke depression

Background

The immune-inflammatory response has been widely considered to be involved in the pathogenesis of post-stroke depression (PSD), but there is ambiguity about the mechanism underlying such association.

Methods

According to Diagnostic and Statistical Manual of Mental Disorders (5th edition), depressive symptoms were assessed at 2 weeks after stroke onset. 15 single nucleotide polymorphisms (SNPs) in genes of indoleamine 2,3-dioxygenase (IDO, including IDO1 and IDO2) and its inducers (including pro-inflammatory cytokines interferon [IFN]-γ, tumor necrosis factor [TNF]-α, interleukin [IL]-1β, IL-2 and IL-6) were genotyped using SNPscan™ technology, and serum IDO1 levels were detected by double-antibody sandwich enzyme-linked immune-sorbent assay.

Results

Fifty-nine patients (31.72%) were diagnosed with depression at 2 weeks after stroke onset (early-onset PSD). The IDO1 rs9657182 T/T genotype was independently associated with early-onset PSD (adjusted odds ratio [OR] = 3.008, 95% confidence interval [CI] 1.157-7.822, p = 0.024) and the frequency of rs9657182 T allele was significantly higher in patients with PSD than that in patients with non-PSD (χ2 = 4.355, p = 0.037), but these results did not reach the Bonferroni significance threshold (p > 0.003). Serum IDO1 levels were also independently linked to early-onset PSD (adjusted OR = 1.071, 95% CI 1.002-1.145, p = 0.044) and patients with PSD had higher serum IDO1 levels than patients with non-PSD in the presence of the rs9657182 T allele but not homozygous C allele (t = -2.046, p = 0.043). Stroke patients with the TNF-α rs361525 G/G genotype had higher serum IDO1 levels compared to those with the G/A genotype (Z = -2.451, p = 0.014).

Conclusions

Our findings provided evidence that IDO1 gene polymorphisms and protein levels were involved in the development of early-onset PSD and TNF-α polymorphism was associated with IDO1 levels, supporting that IDO1 which underlie strongly regulation by cytokines may be a specific pathway for the involvement of immune-inflammatory mechanism in the pathophysiology of PSD.

The potential risk factors of early-onset post-stroke depression from immuno-inflammatory perspective

Background

Mounting evidence strongly uncovered that peripheral immuno-inflammatory response induced by acute stroke is associated with the appearance of post-stroke depression (PSD), but the mechanism remains unclear.

Methods

103 stroke patients were assessed at 2 weeks after onset using Diagnostic and Statistical Manual of Mental Disorders, 5th edition and then divided into PSD and non-PSD groups. Polymorphisms of inflammatory molecules (interleukin [IL]-1β, IL-6, IL-10, IL-18, tumor necrosis factor-α [TNF-α], interferon-γ [IFN-γ] and C-reactive protein [CRP]), complete blood count parameters, splenic attenuation (SA) and splenic volume (SV) on unenhanced chest computed tomography, demographic and other clinical characteristics were obtained. Binary logistic regression model was used to analyze the associations between inflammation-related factors and the occurrence of PSD at 2 weeks after stroke.

Results

49 patients were diagnosed with PSD at 2 weeks after onset (early-onset PSD). The C/T genotypes of CRP rs2794520 and rs1205 were less in PSD group than non-PSD group (both adjusted odds ratio = 3.364; 95%CI: 1.039-10.898; p = 0.043). For CRP rs3091244, the frequency of G allele was higher (80.61% vs. 13.89%) while the frequency of A allele was lower (6.12% vs. 71.30%) in PSD patients than non-PSD patients (χ² = 104.380; p<0.001). SA of PSD patients was lower than that of non-PSD patients in the presence of CRP rs2794520 C/T genotype and rs1205 C/T genotype (both t = 2.122; p = 0.039). Peripheral monocyte count was less in PSD group than non-PSD group (adjusted odds ratio = 0.057; 95%CI: 0.005-0.686; p = 0.024).

Conclusions

CRP polymorphisms, SA based on CRP genotype, and peripheral monocytes are associated with the risk of early-onset PSD, suggesting peripheral immuno-inflammatory activities elicited by stroke in its aetiology.

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.

Blood biomarkers of post-stroke depression after minor stroke at three months in males and females

BACKGROUND

Post-stroke depression (PSD) is one of the most common neuropsychiatric complications after stroke. Studies on the underlying mechanisms and biological markers of sex differences in PSD are of great significance, but there are still few such studies. Therefore, the main objective of this study was to investigate the association of biomarkers with PSD at 3 months after minor stroke in men and women.

METHODS

This was a prospective multicenter cohort study that enrolled 530 patients with minor stroke (males, 415; females, 115). Demographic information and blood samples of patients were collected within 24 h of admission, and followed up at 3 months after stroke onset. PSD was defined as a depressive disorder due to another medical condition with depressive features, major depressive-like episode, or mixed-mood features according to the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-V). Univariate analysis was performed using the chi-square test, Mann-Whitney U test, or t-test. Partial least-squares discriminant analysis (PLS-DA) was used to distinguish between patients with and without PSD. Factors with variable importance for projection (VIP) > 1.0 were classified as the most important factors in the model segregation.

RESULTS

The PLS-DA model mainly included component 1 and component 2 for males and females. For males, the model could explain 13% and 16.9% of the variables, respectively, and 29.9% of the variables in total; the most meaningful predictors were exercise habit and fibrinogen level. For females, the model could explain 15.7% and 10.5% of the variables, respectively, and 26.2% of the variables in total; the most meaningful predictors in the model were brain-derived neurotrophic factor (BDNF), magnesium and free T3. Fibrinogen was positively correlated with the Hamilton Depression Scale-17 items (HAMD-17) score. BDNF, magnesium, and free T3 levels were negatively correlated with the HAMD-17 score.

CONCLUSIONS

This was a prospective cohort study. The most important markers found to be affecting PSD at 3 months were fibrinogen in males, and free T3, magnesium, and BDNF in females.

TRIAL REGISTRATION

ChiCTR-ROC-17013993 .

Alleviative effects of foraging exercise on depressive-like behaviors in chronic mild stress-induced ischemic rat model

BACKGROUND

Poststroke depression (PSD) is a common complication that seriously affects the functional recovery and prognosis of an individual. As some patients with PSD fail to respond to drug therapy, it is urgent to find a viable alternative treatment.

METHODS

An active exercise program known as foraging exercise (FE), using food as bait, was designed. First, focal ischemia and chronic unpredictable mild stress (CUMS) were used to establish a PSD model in rats. FE was then performed for 4 weeks. Body weight and behavioral assessments were conducted at the end of the 4^th and 8^th weeks.

RESULTS

After 8 weeks, the results revealed that, compared with the PSD group, the behavioral scores of the rats in the PSD/FE group were significantly improved, the expression of Iba-1 in the affected frontal lobe and striatum was decreased, and serum levels of IL-6 and the IL-6/IL-10 ratio were downregulated. However, the ratio of residual brain volume in rats that had experienced CUMS was significantly less than that in the stroke group.

CONCLUSION

FE can alleviate the behavioral scores of PSD rats, and its mechanism may be related to a modulation of the immune-inflammation response of microglia. Furthermore, chronic, persistent stress may increase the volume of cerebral infarction after stroke.

Systemic low-grade inflammation and depressive symptomology at chronic phase of ischemic stroke: The chain mediating role of fibrinogen and neutrophil counts

BACKGROUND

Post-stroke depression (PSD) is the most common psychological consequence of stroke. Increased inflammatory markers resulting from ischemic stroke may played an important role in the pathogenesis of depressive symptomology. The present study was conducted to further elucidate the relationship between stroke severity, systemic low-grade inflammation and chronic phase post-stroke depressive symptomology (CP-PSDS).

METHODS

A total of 897 stroke patients were consecutively recruited in this multicenter prospective cohort study and followed up for 1 year. The analytical sample consisted of 436 patients with ischemic stroke (23.4% female, median age = 57 years) from this cohort. Serum concentrations of inflammatory markers were measured in all 436 patients with ischemic stroke, from fasting morning venous blood samples on admission. Stroke severity was evaluated using the National Institutes of Health Stroke Scale (NIHSS) on admission and post-stroke depressive symptomology (PSDS) was evaluated by 17-item Hamilton Rating Scale for Depression (HRSD).

RESULTS

In the fully adjusted models, we observed that 1) NIHSS (Model 2: β = 0.200, 95%CI, 0.057 ∼ 0.332), fibrinogen (Model 2: β = 0.828, 95%CI, 0.269 ∼ 1.435), white blood cell counts (WBC, model 2: β = 0.354, 95%CI, 0.122 ∼ 0.577) and neutrophil counts (Model 2: β = 0.401, 95%CI, 0.126 ∼ 0.655) can independently predict the CP-PSDS after ischemic stroke onset; 2) fibrinogen (Indirect effect = 0.027, 95%CI, 0.007 ∼ 0.063, 13.4% mediated), WBC (Indirect effect = 0.024, 95%CI, 0.005 ∼ 0.058, 11.8% mediated) and neutrophil counts (Indirect effect = 0.030, 95%CI, 0.006 ∼ 0.069, 14.8% mediated) could partially mediate the association between stroke severity and CP-PSDS, and 3) stroke severity might cause CP-PSDS partly through the chain-mediating role of both fibrinogen and neutrophil counts (chain mediated effect = 0.003, 95%CI, 0.000 ∼ 0.011, p = 0.025, 1.6% mediated).

CONCLUSIONS

Findings revealed that fibrinogen, WBC and neutrophil counts may be independent predictors of CP-PSDS and partial mediators of the relationship between stroke severity and CP-PSDS among patients with ischemic stroke. In addition, the chain mediating effect of fibrinogen and neutrophil counts might play an important role in the occurrence of CP-PSDS. However, no inflammatory markers were associated with CP-PSDS in females.

Neuroinflammation as a Key Driver of Secondary Neurodegeneration Following Stroke?

Ischaemic stroke involves the rapid onset of focal neurological dysfunction, most commonly due to an arterial blockage in a specific region of the brain. Stroke is a leading cause of death and common cause of disability, with over 17 million people worldwide suffering from a stroke each year. It is now well-documented that neuroinflammation and immune mediators play a key role in acute and long-term neuronal tissue damage and healing, not only in the infarct core but also in distal regions. Importantly, in these distal regions, termed sites of secondary neurodegeneration (SND), spikes in neuroinflammation may be seen sometime after the initial stroke onset, but prior to the presence of the neuronal tissue damage within these regions. However, it is key to acknowledge that, despite the mounting information describing neuroinflammation following ischaemic stroke, the exact mechanisms whereby inflammatory cells and their mediators drive stroke-induced neuroinflammation are still not fully understood. As a result, current anti-inflammatory treatments have failed to show efficacy in clinical trials. In this review we discuss the complexities of post-stroke neuroinflammation, specifically how it affects neuronal tissue and post-stroke outcome acutely, chronically, and in sites of SND. We then discuss current and previously assessed anti-inflammatory therapies, with a particular focus on how failed anti-inflammatories may be repurposed to target SND-associated neuroinflammation.

The Feasibility of Tai Chi Exercise as a Beneficial Mind-Body Intervention in a Group of Community-Dwelling Stroke Survivors with Symptoms of Depression

Depression is prevalent among one-third to two-thirds of acute and chronic stroke survivors. Despite the availability of pharmacotherapies and/or psychotherapies, depression persists, even for 5–10 years after stroke, reflecting limited treatment responses and/or adherence to this conventional care. Mind-body interventions are commonly used among adults to ameliorate depressive symptoms. Thus, the feasibility of Tai Chi, alongside conventional care, to manage poststroke depression was investigated using a single-group pre-post intervention design. Recruitment and retention, intervention adherence, safety, acceptability, and fidelity were assessed. Symptoms of depression, anxiety, and stress were assessed using standardized questionnaires, objective sleep was assessed via a research-grade triaxial accelerometer, and blood samples were taken to measure oxidative stress, inflammatory markers, and a neurotrophic growth factor using commercially available kits per manufacturer's protocol. Pre-post intervention changes were assessed using paired t-tests. We enrolled stroke survivors (N = 11, mean age = 69.7 ± 9.3) reporting depression symptoms. After the intervention, we observed significant reductions in symptoms of depression (−5.3 ± 5.9, p=0.01), anxiety (−2.2 ± 2.4, p=0.01), and stress (−4.6 ± 4.8, p=0.01), along with better sleep efficiency (+1.8 ± 1.8, p=0.01), less wakefulness after sleep onset (−9.3 ± 11.6, p=0.04), and less time awake (−9.3 ± 11.6, p=0.04). There was a 36% decrease in oxidative stress (p=0.02), though no significant changes in the other biomarkers were found (all p values >0.05). Tai Chi exercise is a feasible intervention that can be used alongside conventional care to manage poststroke depression, aid in reducing symptoms of anxiety and stress, and improve sleep.

Interleukin-10 level is associated with post-stroke depression in acute ischaemic stroke patients

BACKGROUND

Interleukin-10 (IL-10) is a pathophysiological factor in acute ischaemic stroke (AIS) and is relevant to mood disorders after stroke. We evaluated the predictive value of IL-10 in patients with post-stroke depression (PSD).

METHODS

A total of 350 stroke patients were recruited at baseline, and 151 AIS patients were screened and completed a 1-month follow-up. Serum IL-10 levels were measured within 24 h of admission. We used the 17-item Hamilton Depression Scale (HAMD-17) to evaluate depression symptoms; PSD was defined as an HAMD score ≥ 7.

RESULTS

Fifty-one (33.8%) patients showed a more serious stroke degree, larger infarction volume, and poorer daily life activities and prognosis (P < 0.05) and were diagnosed with PSD at the 1-month follow-up. Their IL-10 level decreased significantly compared to the non-PSD group (P < 0.001). After adjusting for confounders, IL-10 could be used as an independent predictor for PSD with an adjusted odds ratio (OR) of 0.615 (95% CI 0.410-0.923, P = 0.019). In addition, the optimal cut-off value of IL-10 was 0.615 pg/mL based on an area under the receiver operating characteristic curve of 0.692 (95% CI 0.604-0.781, P < 0.001), demonstrating that IL-10 could predict the occurrence of PSD. Moreover, IL-10 was an indicator of stroke severity, living ability, and functional outcomes (P < 0.05).

LIMITATIONS

IL-10 was only measured upon admission; dynamic changes need to be further monitored. This was also a single-centre study with a relatively small sample.

CONCLUSIONS

Lower IL-10 levels may be used to predict PSD.

Happiness: A Novel Outcome Measure in Stroke?

In this narrated review, we draw attention to the use of happiness as a novel outcome measure in clinical research studies regarding patients with stroke. Commonly used outcome measures in clinical trials in stroke rehabilitation include the modified Rankin Score (mRS), Functional Impairment Measures (FIM), Barthel Index and quality of life (QoL). Despite being a part of QoL, happiness is arguably a significant construct on its own. While QoL assesses perceptions of various extrinsic aspects of life, happiness may be used as a measure of subjective enjoyment of life after an illness. We review the literature discussing the use of happiness as a formal outcome measure in stroke care and subacute and long-term stroke rehabilitation. Ultimately we recommend the wider use of happiness as an outcome measure where appropriate in these settings.

Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use:

https://youtu.be/iJY-DFLp2WU

The Association Between Systemic Inflammatory Markers and Post-Stroke Depression: A Prospective Stroke Cohort

Objective

Inflammation plays an important role in stroke. Many inflammatory markers in peripheral blood are proved to be associated with stroke severity or prognosis. But few comprehensive models or scales to evaluate the post-stroke depression (PSD) have been reported. In this study, we aimed to compare the level of systemic inflammation markers between PSD and non-PSD patients and explore the association of these inflammatory markers with PSD.

Methods

Totally, 432 ischemic stroke patients were consecutively enrolled in the study and received 1 month follow-up. We used the 17-Hamilton Rating Scale to measure depressive symptoms at 1 month after stroke. With the Hamilton Depression Scale score of >7, patients were diagnosed with PSD. Systemic immune-inflammation index (SII), neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR) and derived neutrophil-to-lymphocyte ratio (dNLR) were calculated from the admission blood work.

Results

Finally, 129 patients (30.5%) were diagnosed with PSD at 1 month. PSD patients showed significantly higher levels of SII (501.27 (345.43-782.58) vs 429.60 (315.64-570.98), P=0.001), NLR (2.36 (1.77-3.82) vs 2.17 (1.56-2.80), P=0.010), dNLR (1.67 (1.30-2.51) vs 1.54 (1.16-1.99), P=0.009), PLR (124.65 (95.25-155.15) vs 109.22 (92.38-142.03), P=0.015), especially SII at admission as compared to non-PSD patients. In the logistic analysis, SII value (>547.30) was independently associated with the occurrence of PSD (OR=2.181, 95% CI=1.274-3.732, p =0.004), better than dNLR (OR=1.833, 95% CI=1.071-3.137, p =0.027), PLR (OR= 1.822, 95% CI=1.063-3.122, p =0.029) and NLR (OR =1.728, 95% CI=1.009-2.958, p =0.046).

Conclusion

Increased SII, PLR, dNLR, NLR, particularly SII at admission, are significantly correlated with PSD and may add some prognostic clues to find early discovery of PSD.

Association of Lymphocyte-to-Monocyte Ratio with Poststroke Depression in Patients with Acute Ischemic Stroke

Background

Poststroke depression (PSD) is a common neuropsychiatric disorder after stroke. The neuroinflammatory response exerts a vital effect in the development of PSD. Lymphocyte-to-monocyte ratio (LMR), a systemic inflammation biomarker, is associated with poor prognosis of acute ischemic stroke (AIS). The purpose of this study was to determine the association between LMR and PSD at 3 months.

Material/Methods

AIS patients (507) were included in this study. Patients were categorized into 3 tertiles and each tertile contains 169 patients: tertile1 (>4.85), tertile 2 (2.96 to 4.85), and tertile 3 (<2.96), based on LMR values and the numbers of patients. PSD was diagnosed with a 17-item Hamilton Depression Scale score of 8 or higher.

Results

Patients (141; 27.8%) were diagnosed with PSD at 3-month follow-up. Patients in the PSD group presented with more severe stroke and lower LMR values (P<0.001). Decreased LMRs were independently associated with occurrence of PSD (middle tertile: odds ratio [OR] 1.823, P=0.037; lowest tertile: OR 3.024, P<0.001). A significant association of a lower LMR value with PSD severity was found (middle tertile: OR 1.883, P=0.031; lowest tertile: OR 2.633, P=0.001). The receiver operating characteristic curve indicates that the optimal threshold of LMR as a predictor for PSD was 3.14, which yielded a sensitivity of 72.4% and a specificity of 68.1%.

Conclusions

Decreased LMR is independently associated with PSD and increased PSD severity.

Toll-like receptor 4-mediated cytokine synthesis and post-stroke depressive symptoms

Altered cytokine synthesis thought to contribute to the pathophysiology of post-stroke depression (PSD). Toll-like receptor 4 (TLR4) is a master regulator of innate immunity. The aim of this study was to explore the putative association between TLR4-mediated cytokine synthesis and subsequent symptoms of PSD. In total, 262 patients with ischemic stroke and without a history of PSD were included. Depressive symptoms were assessed using the Patient Health Questionnaire-9 in 170 patients on Day 8 and in 146 at 3 months after stroke. Blood samples taken on Day 3 after stroke were stimulated ex vivo with lipopolysaccharide (LPS). Ex vivo synthesized cytokines (TNFα, IP-10, IL-1β, IL-6, IL-8, IL-10, and IL-12p70) and circulating cytokines (TNFα, IL-6, sIL-6R, and IL-1ra) were measured using the enzyme-linked immunoassay or cytometric method. RNA sequencing was used to determine the gene expression profile of LPS-induced cytokines and chemokines. LPS-induced cytokine synthesis and the gene expression of TLR4-dependent cytokines and chemokines did not differ between patients with and without greater depressive symptoms. The plasma level of IL-6, but not TNFα, sIL-6R, and IL-1ra, was higher in patients who developed depressive symptoms at 3 months after stroke (median: 4.7 vs 3.4 pg/mL, P = 0.06). Plasma IL-6 predicted the severity of depressive symptoms at 3 months after stroke (β = 0.42, P = 0.03). In conclusion, TLR4-dependent cytokine synthesis was not associated with greater post-stroke depressive symptoms in this study. Circulating IL-6 might be associated with depressive symptoms occurring at 3 months after stroke.

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.

Diabetes, stroke, and neuroresilience: looking beyond hyperglycemia

Ischemic stroke is a leading cause of morbidity and mortality among type 2 diabetic patients. Preclinical and translational studies have identified critical pathophysiological mediators of stroke risk, recurrence, and poor outcome in diabetic patients, including endothelial dysfunction and inflammation. Most clinical trials of diabetes and stroke have focused on treating hyperglycemia alone. Pioglitazone has shown promise in secondary stroke prevention for insulin-resistant patients; however, its use is not yet widespread. Additional research into clinical therapies directed at diabetic pathophysiological processes to prevent stroke and improve outcome for diabetic stroke survivors is necessary. Resilience is the process of active adaptation to a stressor. In patients with diabetes, stroke recovery is impaired by insulin resistance, endothelial dysfunction, and inflammation, which impair key neuroresilience pathways maintaining cerebrovascular integrity, resolving poststroke inflammation, stimulating neural plasticity, and preventing neurodegeneration. Our review summarizes the underpinnings of stroke risk in diabetes, the clinical consequences of stroke in diabetic patients, and proposes hypotheses and new avenues of research for therapeutics to stimulate neuroresilience pathways and improve stroke outcome in diabetic patients.

Post-stroke depression: Chaos to exposition

Cerebral ischemia contributes to significant disabilities worldwide, impairing cognitive function and motor coordination in affected individuals. Stroke has severe neuropsychological outcomes, the major one being a stroke. Stroke survivors begin to show symptoms of depression within a few months of the incidence that overtime progresses to become a long-term ailment. As the pathophysiology for the progression of the disease is multifactorial and complex, it limits the understanding of the disease mechanism completely. Meta-analyses and randomized clinical trials have shown that intervening early with tricyclic antidepressants and selective serotonin receptor inhibitors can be effective. However, these pharmacotherapies possess several limitations that have given rise to newer approaches such as brain stimulation, psychotherapy and rehabilitation therapy, which in today's time are gaining attention for their beneficial results in post-stroke depression (PSD). The present review highlights numerous factors like lesion location, inflammatory mediators and genetic abnormalities that play a crucial role in the development of depression in stroke patients. Further, we have also discussed various mechanisms involved in post-stroke depression (PSD) and strategies for early detection and diagnosis using biomarkers that may revolutionize treatment for the affected population. Towards the end, along with the preclinical scenario, we have also discussed the various treatment approaches like pharmacotherapy, traditional medicines, psychotherapy, electrical stimulation and microRNAs being utilized for effectively managing PSD.

Neuroinflammation and microglia/macrophage phenotype modulate the molecular background of post-stroke depression: A literature review

Increasing evidence hints to the central role of neuroinflammation in the development of post-stroke depression. Danger signals released in the acute phase of ischemia trigger microglial activation, along with the infiltration of neutrophils and macrophages. The increased secretion of proinflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor α (TNFα) provokes neuronal degeneration and apoptosis, whereas IL-6, interferon γ (IFNγ), and TNFα induce aberrant tryptophane degradation with the accumulation of the end-product quinolinic acid in resident glial cells. This promotes glutamate excitotoxicity via hyperexcitation of N-methyl-D-aspartate receptors and antagonizes 5-hydroxy-tryptamine, reducing synaptic plasticity and neuronal survival, thus favoring depression. In the post-stroke period, CX3CL1 and the CD200-CD200R interaction mediates the activation of glial cells, whereas CCL-2 attracts infiltrating macrophages. CD206 positive cells grant the removal of excessive danger signals; the high number of regulatory T cells, IL-4, IL-10, transforming growth factor β (TGFβ), and intracellular signaling via cAMP response element-binding protein (CREB) support the M2 type differentiation. In favorable conditions, these cells may exert efficient clearance, mediate tissue repair, and might be essential players in the downregulation of molecular pathways that promote post-stroke depression.

Immune responses to stroke: mechanisms, modulation, and therapeutic potential

Stroke is the second leading cause of death worldwide and a leading cause of disability. Most strokes are caused by occlusion of a major cerebral artery, and substantial advances have been made in elucidating how ischemia damages the brain. In particular, increasing evidence points to a double-edged role of the immune system in stroke pathophysiology. In the acute phase, innate immune cells invade brain and meninges and contribute to ischemic damage, but may also be protective. At the same time, danger signals released into the circulation by damaged brain cells lead to activation of systemic immunity, followed by profound immunodepression that promotes life-threatening infections. In the chronic phase, antigen presentation initiates an adaptive immune response targeted to the brain, which may underlie neuropsychiatric sequelae, a considerable cause of poststroke morbidity. Here, we briefly review these pathogenic processes and assess the potential therapeutic value of targeting immunity in human stroke.

Elevated neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios predict post-stroke depression with acute ischemic stroke

Post-stroke depression (PSD) is the most prevalent psychiatric complication of acute ischemic stroke. The neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) are indicators of inflammation and are associated with stroke and depression. Therefore, the purpose of the present study was to examine the relationship between NLR/PLR and PSD. Retrospective analysis was carried out in 376 patients with first-ever acute ischemic stroke in the First Affiliated Yijishan Hospital of Wannan Medical College between March 2015 and September 2017. Patients were divided into PSD (n=104; 27.7%) and non-PSD (n=272; 72.3%) groups according to the Diagnostic and Statistical Manual of Mental Disorders-IV criteria at 6 months after stroke. Clinical data were collected retrospectively. NLR and PLR were acquired retrospectively from the routine blood tests performed at admission. A total of 120 healthy volunteers from the physical examination center in the First Affiliated Yijishan Hospital of Wannan Medical College were recruited as controls. Using logistic regression analysis, NLR (≥4.02) and PLR (≥203.74) were independently associated with PSD. NLR, odds ratio (OR) 3.926, 95% confidence intervals (CI, 2.365-7.947), P<0.001; PLR, OR 3.853, 95% CI (2.214-6.632), P=0.002. The ability of the combined index [area under the receiver operating characteristic curve, 0.701; 95% CI (0.622-0.780); P<0.001] to diagnose PSD was greater than that of either ratio alone. Higher NLRs and PLRs (≥4^th quartile) were associated with PSD with a 5.79-fold (P<0.001) increase compared with lower levels of both. Higher NLRs and PLRs were found to be associated with depression 6 months after stroke, and the combined index was more meaningful than either alone in the early clinical detection of PSD.

Severe Periodontitis Is Associated with Early-Onset Poststroke Depression Status

BACKGROUND

Poststroke depression (PSD) is one of the most common complications after ischemic stroke, and periodontitis is associated with depression. However, whether severe periodontitis is associated with early-onset PSD status remains unknown. In this study, we aimed to investigate whether there is an association between severe periodontitis and PSD status in acute ischemic stroke patients.

MATERIAL AND METHODS

We recruited 202 acute ischemic stroke patients within 7 days after stroke onset. Pocket depth and clinical attachment loss were assessed by oral examination to define the severe periodontitis. On the basis of diagnosis of PSD status according to DSM-5 criteria and a 24-item Hamilton Depression Rating Scale score greater than or equal to 8 within 2 weeks after stroke onset, we stratified patients into PSD status or non-PSD status groups and identified the independent predictors for the development of PSD status in multivariate logistic analysis.

RESULTS

77 (38.1%) patients were diagnosed as early-onset PSD status. PSD status group showed more severe periodontitis, lower income, lower Barthel Index (BI) score and Montreal Cognitive Assessment score, higher National Institutes of Health Stroke Scale score and modified Rankin scale (mRS) score compared with non-PSD status group. Multivariate logistic regression showed that severe periodontitis (odds ratio 2.401) and NIHSS score (>4, odds ratio 2.130) were independent predictors for early-onset PSD status.

CONCLUSIONS

Severe periodontitis is found to be an important independent predictor of early-onset PSD status in patients with acute ischemic stroke, in addition to the well-known prognostic factors such as nonminor stroke assessed by NIHSS greater than 4.

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.

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.

High platelet-to-lymphocyte ratio are associated with post-stroke depression

BACKGROUND

Post-stroke depression (PSD) is the most common psychological consequence among stroke patients, and inflammatory cytokines have cited as risk factors in PSD. We aimed to evaluate the predictive value of stratification of PLR (platelet-to-lymphocyte ratio), an inflammatory marker, in PSD patients.

METHODS

A total of 363 acute ischemic stroke (AIS) patients were screened in the study and received 1-month follow-up. All of the patients were categorized into equal tertiles according to the number of patients and the distribution of PLR. PSD status was evaluated by 17-item Hamilton Depression Rating Scale at 1 month after stroke RESULTS: The optimal cut-off points of PLR were: (T1) 42.15-99.60, (T2) 99.72-127.92, (T3) 127.93-259.84. A total of 77 patients (21.2%) were diagnosed with PSD at 1-month follow-up. Significant differences were found between the PSD and non-PSD groups in PLR tertiles of patients (P < 0.001). After adjustment for conventional confounding factors, the odds ratio of PSD was 5.154 (95% CI, 1.933-13.739) for the highest tertile of PLR compared with the lowest tertile. In multiple-adjusted spline regression, continuously PLR showed linear relation with PSD risk after 95 (P < 0.001 for linearity).

LIMITATIONS

We excluded patients with severe aphasia or serious conditions. In addition, the PLR was recorded only at admission, which limited us explore the correlation of the change of PLR over time with PSD CONCLUSIONS: Increased PLR at admission is a significant and independent biomarker to predict the development of PSD, and stratified PLR could strengthen the predictive power for PSD patients.

Post-stroke depression and cognitive impairment: Study design and preliminary findings in a Brazilian prospective stroke cohort (EMMA study)

BACKGROUND

Post-stroke depression (PSD) and cognitive impairment (PCI) are common conditions. This study aims to describe the protocol and preliminary findings of an investigation into factors associated with PSD and PCI 1-3 months after stroke (subacute phase) in survivors from the Study of Stroke Mortality and Morbidity (EMMA study).

METHODS

Stroke patients underwent to clinical and neurological evaluations on admission to hospital. Cerebral magnetic resonance and biomarkers (serotonin, BDNF, IL-6 and IL-18) were carried out in the subacute phase. DSM-IV major depression for the diagnosis of PSD, cognitive functioning for the diagnosis of PCI and functional disability were also recorded at same time.

RESULTS

Of the 103 eligible patients, 85.4% had ischemic stroke and 73.7% had first-ever stroke. In the subacute phase, 27.2% had PCI and 13.6% had current PSD (5.8% with 'first episode' and 7.8% with 'recurrent' depression). PCI was associated with low education (0-7 years of formal education: 75%) and ageing (median age: 70; interquartile range: 59-75 y-old). Left-sided stroke was more frequently associated with increased PCI than right-sided stroke (71.4% vs. 28.4%, p = 0.005). PSD was neither associated with stroke laterality nor tentorial area. Overall, biomarkers levels were not alterated in patients with PSD and PCI.

LIMITATIONS

Findings are based on small sample and less disabled stroke participants, e.g. those without aphasia and deafness.

CONCLUSIONS

Findings reinforce the need of early recognition and rehabilitation of PCI and PSD, mainly among those less educated and with left-sided stroke. PSD might occur through a pathophysiological pathway other than classical depression.

The association between neutrophil-to-lymphocyte ratio and post-stroke depression

BACKGROUND

Post-stroke depression (PSD) is the most common complication occurring among stroke survivors. It has been shown that increased neutrophil-to-lymphocyte ratio (NLR) is associated with depression. We explored the relationship between NLR and PSD.

METHODS

In total, 299 ischemic stroke patients were consecutively enrolled in the study and received 1 month follow-up. The 17-Hamilton Rating Scale was used to measure depressive symptoms at 1 month after stroke. With the Hamilton Depression Scale score of >7, parents were given the DSM-IV criteria for diagnosis of PSD. NLR was computered from the admission blood work. Meanwhile, the control group consisted of 180 healthy volunteers was also recruited.

RESULTS

Seventy-eight patients (26.1%) were diagnosed with PSD at 1 month. PSD patients showed significantly higher levels of NLRs at admission as compared to non-PSD patients as well as normal controls (P < .001). In the logistic analysis, taking NLR values (<3.701) a reference and PSD presence as a dependent variable, NLR values (≥3.70 l) were independently associated with the development of PSD (OR 4.038, 95% CI 2.174-7.500, p < .001).

CONCLUSIONS

Increased NLRs at admission are found to be correlated with PSD and may add prognostic information for the early discovery of 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.

Exosomes in Acquired Neurological Disorders: New Insights into Pathophysiology and Treatment

Exosomes are endogenous nanovesicles that play critical roles in intercellular signaling by conveying functional genetic information and proteins between cells. Exosomes readily cross the blood-brain barrier and have promise as therapeutic delivery vehicles that have the potential to specifically deliver molecules to the central nervous system (CNS). This unique feature also makes exosomes attractive as biomarkers in diagnostics, prognostics, and therapeutics in the context of multiple significant public health conditions, including acquired neurological disorders. The purpose of this review is to summarize the state of the science surrounding the relevance of extracellular vesicles (EVs), particularly exosomes, to acquire neurological disorders, specifically traumatic brain injury (TBI), spinal cord injury (SCI), and ischemic stroke. In total, ten research articles were identified that examined exosomes in the context of TBI, SCI, or stroke; these manuscripts were reviewed and synthesized to further understand the current role of exosomes in the context of acquired neurological disorders. Of the ten published studies, four focused exclusively on TBI, one on both TBI and SCI, and five on ischemic stroke; notably, eight of the ten studies were limited to pre-clinical samples. The present review is the first to discuss the current body of knowledge surrounding the role of exosomes in the pathophysiology, diagnosis, and prognosis, as well as promising therapeutic strategies in TBI, SCI, and stroke research.

Relationship between serum vitamin D levels and inflammatory markers in acute stroke patients

Introduction

Low serum vitamin D levels are associated with the development of poststroke depression (PSD). Inflammatory markers play an important role in pathophysiology of PSD. The relationship between vitamin D levels and inflammatory markers has been discussed in nonstroke individuals. The purposes of this study were to explore the relationship between vitamin D levels and inflammatory markers in acute stroke patients and examine the effect of vitamin D and inflammatory markers on PSD.

Methods

A total of 152 acute stroke patients were recruited. Serum levels of 25-hydroxyvitamin D and inflammatory markers were measured by standardized laboratory methods. Depression symptoms were assessed with the 17-item Hamilton Depression Scale (HAMD-17). Patients with the HAMD-17 scores ≥7 were identified to have depression symptoms.

Results

Serum vitamin D levels were negatively correlated with serum levels of interleukin-6 and high-sensitivity C-reactive protein (hsCRP) (r = -.244, p = .002; r = -.231, p = .004). Multiple regression analysis showed that interleukin-6 and hsCRP levels were associated with vitamin D levels (B = -0.355, p = .003; B = -2.085, p = .006), whereas age, height, weight, leukocyte count, neutrophil ratio, and lymphocyte rate could be omitted without changing the results. In multivariate analyses, the serum levels of vitamin D and interleukin-6 were associated with the development of PSD after adjusted possible variables (OR = 0.976, 95% CI: 0.958-0.994, p = .009; OR = 1.029, 95% CI: 1.003-1.055, p = .027).

Conclusions

Serum vitamin D levels are inversely associated with the levels of interleukin-6 and hsCRP, suggesting a potential anti-inflammatory role for vitamin D in stroke individuals.

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.

Associations of Tumor Necrosis Factor-α and Interleukin-1β Levels and Polymorphisms with Post-Stroke Depression

OBJECTIVE

Proinflammatory cytokines have been implicated in the pathophysiology of post-stroke depression (PSD), and their production levels are influenced by the transcriptional activity of genetic polymorphisms. The present study aimed to investigate the roles of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the serum on the risk of PSD while taking into account the TNF-α -850C/T and -308G/A polymorphisms and the IL-1β -511C/T and +3953C/T polymorphisms.

METHODS

A total of 286 patients were evaluated at 2 weeks post stroke and 222 (78%) of these patients were followed up 1 year later. Depressive (major or minor) disorders were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria during both examinations; evaluations of cytokine concentrations and polymorphisms and demographic and clinical covariates were performed at 2 weeks. The effects of TNF-α and IL-1β concentrations and genotypes on PSD status were investigated using multivariate logistic regression models.

RESULTS

Higher TNF-α levels were associated with PSD at 2 weeks in the presence of the -850T allele with a significant interaction term; higher IL-1β levels were associated with PSD at 2 weeks in the presence of the -511T allele with a borderline significant interaction term and with any +3953C/T polymorphism without a significant interaction term. No associations were found with PSD at 1 year.

CONCLUSIONS

These findings indicate the important roles that TNF-α and IL-1β serum levels play regarding the risk of PSD, particularly during the acute phase of stroke and in patients with genetic susceptibility.

Predictors of early-onset post-ischemic stroke depression: a cross-sectional study

BACKGROUND

Post-stroke depression (PSD) seriously affects the rehabilitation of nerve function and quality of life. However, the pathogenesis of PSD is still not clear. This study aimed to investigate the demographic, clinical, and biochemical factors in patients with PSD.

METHODS

Patients with an acute ischemic stroke, who met the inclusion criteria at Shanghai Tenth People's Hospital from April 2016 to September 2016, were recruited for this study. The stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS), and the mental state was assessed using Mini-Mental State Examination (MMSE), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) at 1 week of admission. The patients were divided into PSD and non-PSD groups. The demographic and clinical characteristics, as well as the biochemical factors, were compared between the two groups. A logistic regression analysis was performed to identify the risk factors for depression following stroke.

RESULTS

A total of 83 patients with acute ischemic stroke were recruited. Of these, 36 (43.4%) developed depression. The multivariate logistic regression analysis indicated that high NIHSS [odds ratio (OR): 1.84, 95% confidence interval (CI): 1.09-3.12, P = 0.023] and high HAMD scores (OR: 2.38, 95% CI: 1.61-3.50, P < 0.001) were independent risk predictors for PSD and so were lower dopamine level (OR: 0.64, 95% CI: 0.45-0.91, P = 0.014), lower 5-hydroxytryptamine level (OR: 0.99, 95% CI: 0.98-1.00, P = 0.046), higher tumor necrosis factor-α level (OR: 1.05, 95% CI: 1.00-1.09, P = 0.044), and lower nerve growth factor level (OR: 0.06, 95% CI: 0.01-0.67, P = 0.022).

CONCLUSIONS

The identification of higher NIHSS scores, higher HAMD scores, lower dopamine level, lower 5-hydroxytryptamine level, higher tumor necrosis factor-α level, and lower nerve growth factor level might be useful for clinicians in recognizing and treating depression in patients after a stroke.

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.

Effects of interleukin-6, interleukin-18, and statin use, evaluated at acute stroke, on post-stroke depression during 1-year follow-up

Proinflammatory cytokines are associated with the development of post-stroke depression (PSD). Statins are thought to possess anti-inflammatory properties but their interactions with cytokines regarding the risk of PSD have yet to be investigated. Thus, the present study aimed to determine whether interleukin (IL)-6 and IL-18 were associated with the development of depression at 2 weeks and 1year after stroke using a longitudinal post-stroke cohort. Furthermore, this study examined the potential interactions between statin use and cytokines on PSD. For this study, 286 patients were evaluated 2 weeks after stroke and 222 patients were followed-up 1year later. Depression was diagnosed using criteria from the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) and then categorized into no PSD or any PSD, which included diagnoses of both major and minor depression. The effects of IL-6 and IL-18 on PSD as well as their interaction with a statin at both examination time-points were investigated using a multivariate logistic regression model. Higher IL-6 and IL-18 levels were independently associated with depressive disorders within 2 weeks and at 1year after stroke. When stratified by statin use, these significant associations were more evident in patients who did not use a statin. Furthermore, there was a significant interaction between statin use and IL-6 on the presence of a depressive disorder at 1year. The present findings support the cytokine hypothesis of PSD and indicate that the preventive effects of statin use against PSD may be mediated by its interactions with IL-6.

Association between inflammatory cytokines and the risk of post-stroke depression, and the effect of depression on outcomes of patients with ischemic stroke in a 2-year prospective study

The association between inflammatory cytokines and the risk of post-stroke depression (PSD) remains unclear. The aim of the present study was to investigate this association and the effect of PSD on the outcomes of ischemic stroke patients. A total of 355 patients who had experienced ischemic stroke participated in inflammatory cytokine detection by ELISA, in addition to depression, quality of life (QOL) and body performance testing. Cox regression was used to evaluate the associations between PSD risk, inflammatory cytokines and the outcomes of patients. Measurement data was evaluated using Student's t test, and counted data was measured by χ² test. The incidence of PSD during the 2-year follow-up was 23.1%. The risk of PSD elevated with increased interleukin (IL)-6 expression levels [hazard ratio (HR)=3.18; 95% confidence interval (CI), 1.37-7.36] following the adjustment of confounders. However, no significant associations were identified between PSD and other inflammatory cytokines. QOL and body performance in the depressed group were significantly worse compared with those in the non-depressed group. The risk of stroke recurrence in patients with depression increased two-fold compared with patients without depression (HR=2.020; 95% CI, 1.123-3.635; P_trend=0.019). No significant associations between PSD and the risk of mortality (HR=1.497; 95% CI, 0.547-4.098) were observed. In conclusion, depression is prevalent in patients following ischemic stroke. IL-6 is positively associated with the risk of PSD, and may predict its development in patients following ischemic stroke. PSD correlates with outcomes of patients, and the effective management of PSD may improve the prognosis of patients.

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.