Peripheral blood cytokines as potential diagnostic biomarkers of suicidal ideation in patients with first-episode drug-naïve major depressive disorder

Factors associated with suicidal ideation in drug-naïve patients with major depressive disorder

BACKGROUND

Inflammation and immune activation may be involved in the pathological processes of depression, but its role in suicidal ideation (SI) in major depressive disorder (MDD) remains to be elucidated. The present study aims to examine the differences of inflammatory markers between MDD patients with and without SI, and to construct a predictive panel using multi index to distinguish SI in MDD patients.

METHODS

A total of 151 first-episode drug-naïve MDD patients were recruited for this study. SI was identified using the Chinese Version of Beck Scale for Suicide Ideation (BSI-CV). Based on the results of this scale, the subjects were divided into two groups: MDD with SI (n = 91) and MDD without SI (n = 60). Hamilton Depression Rating Scale-17 (HAMD-17) was used to assess depression symptoms. Plasma concentrations of interleukin-6 (IL-6), tumor necrosis factor (TNF-α), superoxide dismutase (CAT), and superoxide dismutase (SOD) have been measured.

RESULTS

Age (OR = 0.87, 95%CI 0.81-0.93, p < 0.001), HAMD retardation factor score (OR = 1.49, 95%CI 1.18-1.88, p < 0.001), and plasma IL-6 concentration (OR = 1.03, 95%CI 1.00-1.06, p = 0.041) were statistically significant on SI in MDD patients, we constructed a good predictive panel to distinguish SI in patients with MDD by combining age, marital status, HAMD retardation factor score, and plasma IL-6 concentration (AUC = 0.812, p < 0.001).

LIMITATIONS

The study was cross-sectional, making it impossible to determine directionality or causality.

CONCLUSIONS

Patients with younger age, single status, serious retardation symptom, and higher plasma IL-6 concentrations are more susceptible to experiencing SI in MDD.

Inflammatory chemokines in adolescents' suicide state with depressive disorders

Suicide has become one of the leading causes of death in adolescents and is a direct consequence in patients with depressive disorders. Recently, neuroinflammation has been shown to play a role in the development of depression. This study examined serum chemokine levels in adolescents with depressive disorders at different suicide stages to identify chemokines that discriminate between suicidal behaviors. This study enrolled 111 adolescent patients with depressive disorders who were further subdivided into three groups based on the presence of suicidal behavior or ideation: suicide attempt group (n = 45), suicidal ideation group (n = 44), and non-suicidal depression group (n = 22), along with 23 healthy controls. Eight inflammatory chemokines were detected using the mesoscale discovery method. Patients in the suicide attempters group had higher levels of IL8, MCP-1, Eotaxin, and Eotaxin-3 than those in the non-suicide depression group. Eotaxin-2 had the greatest effect on suicidal behaviors of all factors.

Inflammatory markers and suicidal behavior: A comprehensive review of emerging evidence

BACKGROUND

Suicidal behavior represents a significant public health challenge, and identifying biological markers associated with its risk is critical for prevention and intervention. Emerging evidence suggests a link between inflammation and suicidality, highlighting the role of inflammatory markers as potential biomarkers and therapeutic targets.

METHODS

We conducted a systematic search across four electronic databases, including PubMed, Web of Science, EMBASE, and PsycINFO, to identify studies examining the association between inflammatory markers (e.g., C-reactive protein, interleukin-6, tumor necrosis factor-alpha) and suicidal ideation or behavior.

RESULTS

31 studies met the inclusion criteria. Elevated levels of inflammatory markers were consistently associated with an increased risk of suicidal behavior across diverse populations. This relationship's mechanisms likely involve cytokine-mediated alterations in neurotransmitter systems, neuroplasticity, and stress response pathways. Though robust clinical trials are scarce, preliminary evidence suggests that anti-inflammatory interventions may reduce suicidality.

CONCLUSIONS

Inflammation appears to play a significant role in the pathophysiology of suicidal behavior, offering promising avenues for biomarker development and novel therapeutic strategies. Future research should prioritize longitudinal studies, standardized methodologies, and exploration of personalized anti-inflammatory treatments to better elucidate the inflammation-suicidality link and enhance clinical applicability.

Suicide victims and alcohol-related consumption in Brazil: An observational study and a narrative review of the literature

Deaths due to external causes, mainly suicide, are a severe public health problem in Brazil. Evidence shows that the tendency to impulsive behavior is exacerbated after alcohol consumption. The relationship between alcohol and suicide is poorly described in the medical literature. The study aims to analyze the relationship between victims' blood alcohol levels and suicides in some municipalities in Greater São Paulo, Brazil. We reviewed the data from the medical records of 805 necropsies performed at the Medical Legal Institute of Sao Paulo in Franco da Rocha, Brazil, from 2001 to 2017. The manner of death was established based on the result of police inquiry. Deaths due to suicide (n=41) were selected for the study. Descriptive statistics and Student t-test was applied when appropriate. The variables studied were sex, age, suicide mechanism, and blood alcohol level (BAC). In all cases we could not determine how much time the deceased consumed alcohol before suicide. Of the individuals analyzed, 85.36% were male, and 14.64% were female. The most prevalent age range for males was between 18 and 23 (19.5%). For females, it was between 12 and 23 years (33.2%). Most suicides (48.78%) were due to hanging, followed by self-poisoning (22.08%) and firearms (17.1%). 38 victims (92.68%) presented a positive BAC, over 0.3 mg/dl. The higher levels were in the group of suicide by hanging (2.3 mg/ml). Thus, alcohol intoxication is common among suicide victims, and it can contribute to the fatal outcome as a risk factor. Further studies are necessary for a better comprehension of the effect of alcohol on suicide victims.

Changed ventral striatum structural covariance and grey matter volume in depression during a one-year follow-up

Empirical findings suggest reduced cortico-striatal structural connectivity in patients with major depressive disorder (MDD). However, the relationship between the abnormal structural covariance and one-year outcome of first-episode drug-naive patients has not been evaluated. This longitudinal study aimed to identify specific changes of ventral striatum-related brain structural covariance and grey matter volume in forty-two first-episode patients with major depression disorder compared with thirty-seven healthy controls at the baseline and the one-year follow-up conditions. At the baseline, patients showed decreased structural covariance between the left ventral striatum and the bilateral superior frontal gyrus (SFG), bilateral middle frontal gyrus (MFG), right supplementary motor area (SMA) and left precentral gyrus and increased grey matter volume at the left fusiform and left parahippocampus. At the one-year follow-up, patients showed decreased structural covariance between the left ventral striatum and the right SFG, right MFG, left precentral gyrus and left postcentral gyrus, and increased structural covariance between the right ventral striatum and the right amygdala, right hippocampus, right parahippocampus, right superior temporal pole, right insula and right olfactory bulb and decreased volume at the left SMA compared with controls. These findings suggest that specific ventral striatum connectivity changes contribute to the early brain development of the MDD.

Mental disorders after myocardial infarction: potential mediator role for chemokines in heart-brain interaction?

Acute myocardial infarction (MI) remains one of the leading causes of mortality and morbidity in the global communities. A prevailing topic that has attracted increasing attentions over the past few decades is the so-called heart-brain interaction, in particular following a major traumatic event such as MI. Increased prevalence of depression and other mental disorders has been recognized in cardiac patients after MI, coronary catheterization, or cardiothoracic surgeries. In this review, we focus on the potential pathogenic mechanisms and pre-clinical transcriptomic evidence for identifying potential mediators of post-MI depression. We first summarize the conventional mechanistic understanding that leads to the current clinical management of post-MI depression with the use of selective serotonin reuptake inhibitors (SSRIs) and cognitive behavior and exercise therapies. We further envisage a possible role played by certain chemokines, e.g., Chemokine (C-X-C motif) ligand 12 (CXCL12) and Chemokine (C-C motif) ligand 2 (CCL22), in serving as signaling molecules to connect the MI-induced heart damage to the pro-depressive changes in brain during the post-MI period. Future in-depth investigations into this chemokine hypothesis will be instrumental in developing new chemokine-targeted therapies for better management of the cardiac patients suffering from post-MI depression.

Causal relationships between serum albumin, neuroticism and suicidal ideation in depressed patients: A Mendelian randomization study

Although serum albumin and neuroticism have revealed a strong association with suicidal ideation in individuals with depression, the causal relationship between them is uncertain. This study analyzed the causal association of serum albumin, neuroticism and suicidal ideation using large-scale GWAS data and Univariable Mendelian Randomization (UVMR) methods. The Multivariable MR (MVMR) analysis was used to explore the causal pathways. UVMR analysis revealed that genetically determined serum albumin is causally associated with neuroticism (β = -0.006 S.D.; 95 % CI: 0.009, -0.002; p = 0.003) and suicidal ideation (β = 0.009 S.D.; 95 % CI: 0.001, 0.016; p = 0.037); and that neuroticism mediates 100 % of the causal association between serum albumin and suicidal ideation in individuals with depression. These findings suggest genetic evidence for the causal effect of serum albumin on suicidal ideation in depressed patients and the significant mediation effect of neuroticism on this causal association. This study proves the protective role of serum albumin for neuroticism and the riskiness of personality traits for suicidal ideation in individuals with depression.

Serum indoleamine 2, 3-dioxygenase and tryptophan-2, 3-dioxygenase: potential biomarkers for the diagnosis of major depressive disorder

OBJECTIVE

The objective of this study was to observe the changes in the levels of indoleamine 2, 3-dioxygenase (IDO) and tryptophan-2, 3-dioxygenase (TDO) in patients with major depressive disorder (MDD) and investigate their potential role as novel biomarkers for diagnosing MDD.

METHODS

A total of 55 MDD patients and 55 healthy controls (HC) were enrolled in the study. The severity of MDD was assessed using the 24-item Hamilton Depression Rating Scale (HAMD-24) before and after treatment. The serum concentrations of IDO and TDO were measured at baseline and after treatment. The correlations between the serum levels of IDO and TDO and HAMD-24 scores were evaluated using Pearson's correlation test. Receiver operating characteristic (ROC) curve analysis was used to evaluate the area under the curve (AUC) of serum levels of IDO and TDO for discriminating MDD patients from HC.

RESULTS

The serum IDO and TDO concentrations were significantly higher in patients with MDD at baseline than in healthy controls, and decreased significantly after 2 weeks or 1 month of treatment. The levels of IDO and TDO were significantly positively correlated with HAMD-24 scores. Furthermore, the AUC values for IDO and TDO were 0.999 and 0.966, respectively.

CONCLUSION

The study suggests that serum IDO and TDO may serve as novel biomarkers for diagnosing MDD. These findings may lead to a better understanding of the pathogenesis of MDD and the development of new therapeutic targets.

The Relationship Between CYP46A1 Polymorphism and Suicide Risk: A Preliminary Investigation

Suicide is a global public health issue, with a particularly high incidence in individuals suffering from Major Depressive Disorder (MDD). The role of cholesterol in suicide risk remains controversial, prompting investigations into genetic markers that may be implicated. This study examines the association between CYP46A1 polymorphisms, specifically SNPs rs754203 and rs4900442, and suicide risk in a Mexican MDD patient cohort. Our study involved 188 unrelated suicide death victims, 126 MDD patients, and 144 non-suicidal controls. Genotypic and allelic frequencies were assessed using the Real Time-polymerase chain reaction method, and associations with suicide risk were evaluated using chi-square tests. The study revealed significant differences in allelic and genotypic frequencies in rs754203 SNP between suicide death and controls. The CYP46A1 rs754203 genotype G/G was significantly linked with suicide, and the G allele was associated with a higher risk of suicide (OR = 1.370, 95% CI = 1.002-1.873). However, we did not observe any significant differences in genotype distribution or allele frequencies of CYP46A1 rs4900442. Our study suggests that carriers of the CYP46A1 rs754203 G allele (A/G + G/G) may play a role in suicidal behavior, especially in males. Our findings support that the CYP46A1 gene may be involved in susceptibility to suicide, which has not been investigated previously. These results underscore the importance of further research in different populations to elucidate the genetic underpinnings of the role of CYP46A1 in suicide risk and to develop targeted interventions for at-risk populations.

Sex differences in serum trace elements and minerals levels in unmedicated patients with major depressive episode: The role of suicidal ideation

BACKGROUND

We aimed to examine the influence of gender on serum trace elements and minerals levels in depression, as well as the impact of suicidal ideation (SI) on these gender dimorphisms.

METHODS

A total of 260 unmedicated patients with a current major depressive episode were enrolled. The Beck Scale for Suicide Ideation was utilized to evaluate SI. The serum levels of copper, zinc, iron, calcium, phosphorus, and magnesium were quantified.

RESULTS

Within the non-SI (NSI) group, females exhibited higher levels of copper (p = 0.001) and phosphorus (p = 0.008), and lower levels of zinc (p = 0.022) and calcium (p = 0.008) compared to males. Conversely, no discernible gender disparities were observed in the SI group (all p > 0.05). Also, no group differences in these trace elements/minerals were observed between the SI and NSI groups (all p > 0.05). Notably, serum iron levels exhibited a significant group-by-sex interaction effect (p = 0.024). Further analysis revealed that iron levels were higher in the SI group than in the NSI group among females (p = 0.048), but lower in females than in males within the NSI group (p < 0.001). Moreover, a positive association between the fourth quantile of serum iron and SI was detected in females (odds ratio [OR] = 2.88, 95 % confidence interval [CI]: 1.08-8.11).

CONCLUSIONS

Gender effects on serum trace element/mineral levels were different in depressed patients with and without SI. Female patients were susceptible to SI when serum iron was at the upper end of normal.

Cytokine profile in first-episode drug-naïve major depressive disorder patients with or without anxiety

OBJECTIVE

It is known that cytokines play a role in both depression and anxiety. This study aimed to compare the levels of multiple cytokines in patients with first-episode drug-naive major depressive disorder (MDD) with or without anxiety and analyze the correlation between the level of depression or anxiety and the serum cytokine levels.

METHODS

The study involved 55 patients with first-episode drug-naive MDD. To assess anxiety symptoms, the 14-item HAMA was used. MDD patients were divided into two groups: 23 MDD patients without anxiety and 32 MDD patients with anxiety. The measurement of 37 cytokines was conducted. Serum cytokine levels between patients with MDD without anxiety and anxiety were compared. In multiple linear regression models, the relationship between the group and abnormal cytokines was explored. The receiver operating characteristic (ROC) curve analysis was performed to estimate diagnostic performance of serum cytokines in discriminating MDD patients with anxiety from MDD patients without anxiety. A correlation was evaluated between the scores of HAMD or HAMA and the serum cytokine levels.

RESULTS

In MDD patients with anxiety, IL-17 C and CCL17 levels were significantly lower than in MDD patients without anxiety (all P < 0.05). Multiple measurements were corrected with Benjamini-Hochberger corrections, but none of these differences persisted (all P > 0.05). The results of multiple linear regression models revealed that after controlling for other independent variables, group was not a significant independent predictor of serum IL-17 C or CCL17 (all P > 0.05). The AUC values of IL-17 C and CCL17 were 0.643 and 0.637, respectively, in discriminating MDD patients with anxiety from MDD patients without anxiety. The results of partial correlation analyses showed the scores of HAMD were negatively correlated with the IL-17 C (r = -0.314, P = 0.021) levels with sex as a covariate.

CONCLUSIONS

The findings suggest that there is a potential absence of disparity in the levels of circulating cytokines among individuals diagnosed with first-episode drug-naïve MDD, regardless of the presence or absence of comorbid anxiety.

Potential Inflammatory Biomarkers for Major Depressive Disorder Related to Suicidal Behaviors: A Systematic Review

Major depressive disorder (MDD) is a highly prevalent psychiatric condition affecting an estimated 280 million individuals globally. Despite the occurrence of suicidal behaviors across various psychiatric conditions, MDD is distinctly associated with the highest risk of suicide attempts and death within this population. In this study, we focused on MDD to identify potential inflammatory biomarkers associated with suicidal risk, given the relationship between depressive states and suicidal ideation. Articles published before June 2023 were searched in PubMed, Embase, Web of Science, and the Cochrane Library to identify all relevant studies reporting blood inflammatory biomarkers in patients with MDD with suicide-related behaviors. Of 571 articles, 24 were included in this study. Overall, 43 significant biomarkers associated with MDD and suicide-related behaviors were identified. Our study provided compelling evidence of significant alterations in peripheral inflammatory factors in MDD patients with suicide-related behaviors, demonstrating the potential roles of interleukin (IL)-1β, IL-6, C-reactive protein, C-C motif chemokine ligand 2, and tumor necrosis factor-α as biomarkers. These findings underscore the intricate relationship between the inflammatory processes of these biomarkers and their interactions in MDD with suicidal risk.