MANF/EWSR1/ANXA6 pathway might as the bridge between hypolipidemia and major depressive disorder

Annexin A: Cell Death, Inflammation, and Translational Medicine

The annexin superfamily proteins, a family of calcium-dependent phospholipid-binding proteins, are involved in a variety of Ca²+-regulated membrane events. Annexin A, expressed in vertebrates, has been implicated in a variety of regulated cell death (RCD) pathways, including apoptosis, autophagy, pyroptosis, ferroptosis, and neutrophil extracellular trap-induced cell death (NETosis). Given that inflammation is a key driver of cell death, the roles of Annexin A in inflammation have been extensively studied. In this review, we discuss the regulatory roles of Annexin A in RCD and inflammation, the development of related targeted therapies in translational medicine, and the application of animal models to study these processes. We also analyze current challenges and discuss future directions for improved diagnostic and therapeutic strategies.

Landscapes of gut microbiome and blood metabolomic signatures in relapsing remitting multiple sclerosis

Although disturbances in the gut microbiome have been implicated in multiple sclerosis (MS), little is known about the changes and interactions between the gut microbiome and blood metabolome, and how these changes affect disease-modifying therapy (DMT) in preventing the progression of MS. In this study, the structure and composition of the gut microbiota were evaluated using 16S rRNA gene sequencing and an untargeted metabolomics approach was used to compare the serum metabolite profiles from patients with relapsing-remitting MS (RRMS) and healthy controls (HCs). Results indicated that RRMS was characterized by phase-dependent α-phylogenetic diversity and significant disturbances in serum glycerophospholipid metabolism. Notably, α-phylogenetic diversity was significantly decreased in RRMS patients during the chronic phase (CMS) compared with those in the acute phase (AMS). A distinctive combination of two elevated genera (Slackia, Lactobacillus) and five glycerophospholipid metabolism-associated metabolites (four increased: GPCho(22:5/20:3), PC(18:2(9Z,12Z)/16:0), PE(16:0/18:2(9Z,12Z)), PE(18:1(11Z)/18:2(9Z,12Z)); one decreased: PS(15:0/22:1(13Z))) in RRMS patients when comparing to HCs. Moreover, a biomarker panel consisting of four microbial genera (three decreased: Lysinibacillus, Parabacteroides, UBA1819; one increased: Lachnoanaerobaculum) and two glycerophospholipid metabolism-associated metabolites (one increased: PE(P-16:0/22:6); one decreased: CL(i-12:0/i-16:0/i-17:0/i-12:0)) effectively discriminated CMS patients from AMS patients, which indicate correlation with higher disability. Additionally, DMTs appeared to attenuate MS progression by reducing UBA1819 and upregulating CL(i-12:0/i-16:0/i-17:0/i-12:0). These findings expand our understanding of the microbiome and metabolome roles in RRMS and may contribute to identifying novel diagnostic biomarkers and promising therapeutic targets.

The immunological perspective of major depressive disorder: unveiling the interactions between central and peripheral immune mechanisms

Major depressive disorder is a prevalent mental disorder, yet its pathogenesis remains poorly understood. Accumulating evidence implicates dysregulated immune mechanisms as key contributors to depressive disorders. This review elucidates the complex interplay between peripheral and central immune components underlying depressive disorder pathology. Peripherally, systemic inflammation, gut immune dysregulation, and immune dysfunction in organs including gut, liver, spleen and adipose tissue influence brain function through neural and molecular pathways. Within the central nervous system, aberrant microglial and astrocytes activation, cytokine imbalances, and compromised blood-brain barrier integrity propagate neuroinflammation, disrupting neurotransmission, impairing neuroplasticity, and promoting neuronal injury. The crosstalk between peripheral and central immunity creates a vicious cycle exacerbating depressive neuropathology. Unraveling these multifaceted immune-mediated mechanisms provides insights into major depressive disorder's pathogenic basis and potential biomarkers and targets. Modulating both peripheral and central immune responses represent a promising multidimensional therapeutic strategy.

Retrospective evaluation of novel serum inflammatory biomarkers in first-episode psychiatric disorders: diagnostic potential and immune dysregulation

Background

This study assessed the diagnostic capabilities of eight inflammatory biomarkers in first-episode schizophrenia (SCZ), bipolar disorder (BD), and depression (D), examining their differential expression across these psychiatric disorders. The markers studied include neutrophils/lymphocyte ratio (NLR), aggregate index of systemic inflammation (AISI), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), lymphocytes/high-density lipoprotein (HDL) ratio (LHR), monocytes/HDL ratio (MHR), neutrophils/HDL ratio (NHR), and platelets/HDL ratio (PHR).

Methods

We conducted a retrospective observational study involving 335 individuals with SCZ, 68 with BD, 202 with D, and 282 healthy controls (C) to evaluate hematologic parameters from untreated patients and controls.

Results

Significant differences in biomarker levels were found between patient groups and controls. Logistic regression analysis indicated that NHR and MHR (p < 0.001), as well as LHR and NLR (p < 0.01), were predictive factors for SCZ. MHR was a predictive factor for BD (p < 0.05). NHR (p < 0.01) and MHR (p < 0.001) were predictive factors for distinguishing between D and C. The area under the curve (AUC) value of the NHR + MHR + NLR composite index model for the SCZ group was 0.846 (p < 0.001). In the BD group, the AUC value for the MHR was 0.816 (p < 0.001). The D group's combined AUC value of NHR + MHR was 0.824 (p < 0.001).

Conclusion

This study highlights the diagnostic value of inflammatory biomarkers in distinguishing SCZ, BD, and D based on their differential expression.

Mesencephalic Astrocyte-Derived Neurotrophic Factor (MANF) Mitigates Neuroinflammation and Cognitive Impairment by Modulating Glial Activation in Sepsis-Associated Encephalopathy

Sepsis-associated encephalopathy (SAE) is a severe neurological complication of sepsis, characterized by cognitive impairment and increased mortality. Owing to the established neuroprotective and immunomodulatory effects of Mesencephalic Astrocyte-derived Neurotrophic Factor (MANF) in a plethora of neurological disorders, our study aimed to investigate the role of MANF in SAE and evaluate its potential as a therapeutic target. Employing a cecal ligation and puncture (CLP) mouse model of sepsis, we analyzed MANF expression in the hippocampus and cortex, and evaluated the influence of intranasally administered recombinant human MANF (rhMANF) on symptoms of SAE. Our results disclosed a substantial increase in MANF protein levels within the hippocampus and cortex of septic mice, primarily found in neurons. Post-CLP surgical administration of rhMANF led to numerous favorable outcomes. Specifically, rhMANF therapy mitigated sepsis-induced behavioral deviations and cognitive impairments, as gauged by SHIRPA scores and Morris water maze tests, and enhanced survival rates in septic mice. These enhancements were concomitant with alterations in neuroinflammation and synaptic integrity. The rhMANF treatment attenuated activation of microglia and astrocytes in the hippocampus and cortex, as evidenced by diminished Iba-1 and GFAP positive cells. It also curtailed the generation of pro-inflammatory cytokines TNF-α and IL-6, and obstructed the p38 MAPK inflammatory pathway. Moreover, rhMANF sustained the expression of synaptic proteins PSD95 and SYN, and conserved neuronal integrity, as demonstrated by Nissl staining. In conclusion, our study underscores the potential of MANF as an innovative therapeutic target for SAE, emphasizing its anti-inflammatory and neuroprotective capabilities.

Elevated SCN11A concentrations associated with lower serum lipid levels in patients with major depressive disorder

The pathogenesis of major depressive disorder (MDD) involves lipid metabolism. Our earlier research also revealed that MDD patients had much lower total cholesterol (TC) concentrations than healthy controls (HCs). However, it is still unclear why TC decreased in MDD. Here, based on the Ingenuity Knowledge Base's ingenuity pathway analysis, we found that sodium voltage-gated channel alpha subunit 11A (SCN11A) might serve as a link between low lipid levels and MDD. We analyzed the TC levels and used ELISA kits to measure the levels of SCN11A in the serum from 139 MDD patients, and 65 HCs to confirm this theory and explore the potential involvement of SCN11A in MDD. The findings revealed that TC levels were considerably lower and SCN11A levels were remarkably increased in MDD patients than those in HCs, while they were significantly reversed in drug-treatment MDD patients than in drug-naïve MDD patients. There was no significant difference in SCN11A levels among MDD patients who used single or multiple antidepressants, and selective serotonin reuptake inhibitors or other antidepressants. Pearson correlation analysis showed that the levels of TC and SCN11A were linked with the Hamilton Depression Rating Scales score. A substantial association was also found between TC and SCN11A. Moreover, a discriminative model made up of SCN11A was discovered, which produced an area under a curve of 0.9571 in the training set and 0.9357 in the testing set. Taken together, our findings indicated that SCN11A may serve as a link between low lipid levels and MDD, and showed promise as a candidate biomarker for MDD.

TCF4 and RBFOX1 as peripheral biomarkers for the differential diagnosis and treatment of major depressive disorder

BACKGROUND

Recent genome-wide association studies on major depressive disorder (MDD) have indicated the involvement of LRFN5 and OLFM4; however, the expression levels and roles of these molecules in MDD remain unclear. The present study aimed to determine the serum levels of TCF4 and RBFOX1 in patients with MDD and to investigate whether these molecules could be used as biomarkers for MDD diagnosis.

METHODS

The study included 99 drug-naïve MDD patients, 90 drug-treated MDD patients, and 81 healthy controls (HCs). Serum TCF4 and RBFOX1 levels were measured by ELISA. Pearson's correlation analysis was conducted to determine the association between TCF4/RBFOX1 and clinical variables. Linear support vector machine classifier was used to evaluate the diagnostic capabilities of TCF4 and RBFOX1.

RESULTS

Serum TCF4 and RBFOX1 levels were substantially higher in MDD patients than in HCs and significantly lower in drug-treated MDD patients than in drug-naïve MDD patients. Moreover, serum TCF4 and RBFOX1 levels were associated with the Hamilton Depression Scale score, duration of illness, serum lipids levels, and hepatic function. Thus, both these molecules showed potential as biomarkers for MDD. TCF4 and RBFOX1 combination exhibited a higher diagnostic performance, with the mean area under the curve values of 0.9861 and 0.9936 in the training and testing sets, respectively.

LIMITATIONS

Small sample size and investigation of only the peripheral nervous system.

CONCLUSIONS

TCF4 and RBFOX1 may be involved in the pathogenesis of MDD, and their combination may serve as a diagnostic biomarker panel for MDD.

Serum levels of interleukin-33 and mesencephalic astrocyte derived neurotrophic factors in patients with major depressive disorder: a cross-sectional comparative design

BACKGROUND

Major depressive disorder (MDD) is a debilitating health condition that has significant morbidity and mortality rates. Depression can be caused due to social, biological, environmental, psychological, and genetic factors. A few biological processes have been proposed as the pathophysiological pathways of depression. Neurotrophic factors and inflammatory cytokines have been linked to depression. Thus, we aimed to investigate the serum interleukin-33 (IL-33) and mesencephalic astrocyte-derived neurotrophic factor (MANF) in MDD patients and corresponding healthy controls (HCs).

METHOD

This study involved the inclusion of 129 MDD patients and 125 HCs matched by sex and age. A psychiatrist evaluated the study participants following DSM-5 criteria. The severity of the illness was assessed utilizing the Hamilton Depression Rating Scale (Ham-D). The serum concentrations of IL-33 and MANF were measured using enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

The mean serum levels of IL-33 were decreased (159.12 ± 6.07 pg/ml vs. 180.60 ± 8.64 pg/ml, p = 0.042), and the MANF levels were increased (5.40 ± 0.19 ng/ml vs. 4.46 ± 0.21 ng/ml, p = 0.001) in MDD patients when compared to HCs.

CONCLUSIONS

The current study proposes that lower IL-33 and higher MANF serum levels are associated with MDD progression and depression severity. These biomarkers could be used as risk assessment tools for MDD. We recommend more investigation, including a significant population, to determine the precise function of IL-33 and MANF in depression.

CDNF and MANF in the brain dopamine system and their potential as treatment for Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by gradual loss of midbrain dopamine neurons, leading to impaired motor function. Preclinical studies have indicated cerebral dopamine neurotrophic factor (CDNF) and mesencephalic astrocyte-derived neurotrophic factor (MANF) to be potential therapeutic molecules for the treatment of PD. CDNF was proven to be safe and well tolerated when tested in Phase I-II clinical trials in PD patients. Neuroprotective and neurorestorative effects of CDNF and MANF were demonstrated in animal models of PD, where they promoted the survival of dopamine neurons and improved motor function. However, biological roles of endogenous CDNF and MANF proteins in the midbrain dopamine system have been less clear. In addition to extracellular trophic activities, CDNF/MANF proteins function intracellularly in the endoplasmic reticulum (ER), where they modulate protein homeostasis and protect cells against ER stress by regulating the unfolded protein response (UPR). Here, our aim is to give an overview of the biology of endogenous CDNF and MANF in the brain dopamine system. We will discuss recent studies on CDNF and MANF knockout animal models, and effects of CDNF and MANF in preclinical models of PD. To elucidate possible roles of CDNF and MANF in human biology, we will review CDNF and MANF tissue expression patterns and regulation of CDNF/MANF levels in human diseases. Finally, we will discuss novel findings related to the molecular mechanism of CDNF and MANF action in ER stress, UPR, and inflammation, all of which are mechanisms potentially involved in the pathophysiology of PD.

LRFN5 and OLFM4 as novel potential biomarkers for major depressive disorder: a pilot study

Evidences have shown that both LRFN5 and OLFM4 can regulate neural development and synaptic function. Recent genome-wide association studies on major depressive disorder (MDD) have implicated LRFN5 and OLFM4, but their expressions and roles in MDD are still completely unclear. Here, we examined serum concentrations of LRFN5 and OLFM4 in 99 drug-naive MDD patients, 90 drug-treatment MDD patients, and 81 healthy controls (HCs) using ELISA methods. The results showed that both LRFN5 and OLFM4 levels were considerably higher in MDD patients compared to HCs, and were significantly lower in drug-treatment MDD patients than in drug-naive MDD patients. However, there were no significant differences between MDD patients who received a single antidepressant and a combination of antidepressants. Pearson correlation analysis showed that they were associated with the clinical data, including Hamilton Depression Scale score, age, duration of illness, fasting blood glucose, serum lipids, and hepatic, renal, or thyroid function. Moreover, these two molecules both yielded fairly excellent diagnostic performance in diagnosing MDD. In addition, a combination of LRFN5 and OLFM4 demonstrated a better diagnostic effectiveness, with an area under curve of 0.974 in the training set and 0.975 in the testing set. Taken together, our data suggest that LRFN5 and OLFM4 may be implicated in the pathophysiology of MDD and the combination of LRFN5 and OLFM4 may offer a diagnostic biomarker panel for MDD.