Metabolic profiles revealed synergistically antidepressant effects of lilies and Rhizoma Anemarrhenae in a rat model of depression

Circulating metabolites and depression: a bidirectional Mendelian randomization

Background

Studies have shown an association between depression and circulating metabolites, but the causal relationship between them has not been elucidated. The purpose of this study was to elucidate the causal relationship between circulating metabolites and depression and to explore the role of circulating metabolites in depression.

Methods

In this study, the top single-nucleotide polymorphisms (SNPs) associated with circulating metabolites (n = 24,925) and depression (n = 322,580) were obtained based on the publicly available genome-wide association study using two-sample Mendelian randomization (MR). SNP estimates were summarized through inverse variance weighted, MR Egger, weighted median, MR pleiotropy residual sum and outlier, and "leave-one-out" methods.

Results

Apolipoprotein A-I (OR 0.990, 95% CI 981-0.999) and glutamine (OR 0.985, 95% CI 0.972-0.997) had protective causal effects on depression, whereas acetoacetate (OR 1.021, 95% CI 1.009-1.034), glycoproteins (OR 1.005, 95% CI 1.000-1.009), isoleucine (OR 1.013, 95% CI 1.002-1.024), and urea (OR 1.020, 95% CI 1.000-1.039) had an anti-protective effect on depression. Reversed MR showed no effect of depression on the seven circulating metabolites.

Conclusion

In this study, MR analysis showed that apolipoprotein A-I and glutamine had a protective effect on depression, and acetoacetate, glycoprotein, isoleucine, glucose, and urea may be risk factors for depression. Therefore, further research must be conducted to translate the findings into practice.

Zhi-Zi-Chi Decoction Reverses Depressive Behaviors in CUMS Rats by Reducing Oxidative Stress Injury Via Regulating GSH/GSSG Pathway

Depression is one of the main diseases that lead to disability and loss of ability to work. As a traditional Chinese medicine, Zhi-zi-chi decoction is utilized to regulate and improve depression. However, the research on the antidepressant mechanism and efficacy material basis of Zhi-zi-chi decoction has not been reported yet. Our previous research has found that Zhi-Zi-chi decoction can reduce glutamate-induced oxidative stress damage to PC 12 cells, which can exert a neuroprotective effect, and the antidepressant effect of Zhi-Zi-chi decoction was verified in CUMS rat models. In this study, the animal model of depression was established by chronic unpredictable mild stimulation combined with feeding alone. The brain metabolic profile of depressed rats was analyzed by the method of metabolomics based on ultra-performance liquid chromatography-quadrupole/time-of-flight mass. 26 differential metabolites and six metabolic pathways related to the antidepressant of Zhi-zi-chi decoction were screened and analyzed. The targeted metabolism of the glutathione metabolic pathway was analyzed. At the same time, the levels of reactive oxygen species, superoxide dismutase, glutathione reductase, glutathione peroxidase in the brain of depressed rats were measured. Combined with our previous study, the antioxidant effect of the glutathione pathway in the antidepressant effect of Zhi-zi-chi decoction was verified from the cellular and animal levels respectively. These results indicated that Zhi-zi-chi decoction exerted a potential antidepressive effect associated with reversing the imbalance of glutathione and oxidative stress in the brain of depressed rats.

Baihe Extracts Reduce the Activation and Apoptosis of Microglia in the Hippocampus of Mice with Depression-like Behaviors by Downregulating MYC

The purpose of our investigation is to identify the potential effects and key molecular targets of Baihe extracts in depression treatment. Network meta-analysis was applied for the synthesis of efficacy outcomes of fluoxetine and three traditional Chinese medicine Baihe prescriptions in depression. Depression-related target genes were screened using "GeneCards" database and "Comparative Toxicogenomics Database (CTD)". The major active components and targets of Baihe were screened using the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. The identified depression-related genes and the target genes of Baihe were intersected, an interaction network was constructed using the "String" database, and key target genes were determined based on their degree value. Functional enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) profiles was performed using the "ClusterProfiler" R package. A mouse model with depression-like behaviors was constructed to verify the putative roles of the in silico identified key genes. Microglia were isolated from the mouse hippocampus, and the effects of Baihe extract-containing serum on microglia activation and apoptosis by targeting the key genes were examined in vitro. The meta-analysis results revealed no obvious differences in depression treatment efficacy between fluoxetine and the three Baihe prescriptions, suggesting Baihe extracts as a safe and effective alternative treatment for depression. Using network pharmacology and bioinformatics analysis, Baihe extracts were found to modulate depression by regulating 15 key genes, with MYC as the key gene. Subsequent animal experiments demonstrated that Baihe extracts reduced depression-related behavior, microglial activation, and inflammatory mediator release in mice by inhibiting MYC. Serum containing Baihe extracts could inhibit the activation of microglia and the release of inflammatory mediators by downregulating MYC. In summary, Baihe extracts were found to diminish MYC expression to reduce microglial activation and inflammatory factor release, thereby exerting antidepressant effects.

Inflamed brain: Targeting immune changes and inflammation for treatment of depression

Although there are a number of clinically effective treatments for depression, many patients exhibit treatment resistance. Recent clinical and preclinical studies reveal that peripheral and brain immune changes and inflammation are involved in the pathophysiology of depression. This 'Inflamed Brain' research provides critical clues for understanding of disease pathophysiology and many candidate molecules that are potentially useful for identifying novel drug targets for the treatment of depression. In this review, we will present clinical evidence on the role of inflammation in the pathophysiology of depression. We will also summarize current clinical trials which test drugs targeting inflammation for the treatment of patients with depression. Furthermore, we will briefly provide preclinical evidence demonstrating altered immune system function and inflammation in stress-induced animal models and will discuss the future potential of inflammation-related drug targets. Collectively, inflammatory signatures identified in clinical and preclinical studies may allow us to stratify depressive patients based on biotypes, contributing to the development of novel mechanism-based interventions that target specific patient populations.

Molecular mechanism of Epicedium treatment for depression based on network pharmacology and molecular docking technology

BACKGROUND

Increasing attention has been paid to the effect of Epimedium on the nervous system, particularly anti-depression function. In the present study, we applied network pharmacology to introduce a testable hypothesis on the multi-target mechanisms of Epicedium against depression.

METHODS

By reconstructing the network of protein-protein interaction and drug-component-target, we predicted the key protein targets of Epicedium for the treatment of depression. Then, through molecular docking, the interaction of the main active components of Epicedium and predicted candidate targets were verified.

RESULTS

Nineteen active compounds were selected from Epicedium. There were 200 targets associated with Epicedium and 537 targets related to depression. The key targets of Epicedium for treating depression were IL6, VEGFA, AKT1, and EGF. According to gene ontology functional enrichment analysis, 22 items of biological process (BP), 13 items of cell composition (CC) and 9 items of molecular function (MF) were obtained. A total of 56 signaling pathways (P < 0.05) were identified by Kyoto Encyclopedia of Genes and Genomes analysis, mainly involving depression-related pathways such as dopaminergic synapse, TNF signaling pathway, and prolactin signaling pathway. The results of molecular docking showed that the most important activity components, including luteoklin, quercetin and kaempferol, were well combined with the key targets.

CONCLUSIONS

Luteoklin, quercetin, kaempferol and other active compounds in Epicedium can regulate multiple signaling pathways and targets such as IL6, AKT1, and EGF, therefore playing therapeutic roles in depression.

Emerging application of metabolomics on Chinese herbal medicine for depressive disorder

Depressive disorder is a kind of emotional disorder that is mainly manifested with spontaneous and persistent low mood. Its etiology is complex and still not fully understood. Metabolomics, an important part of system biology characterized by its integrity and systematicness, analyzes endogenous metabolites of small molecules in vivo and examines the metabolic status of the organism. It is widely used in the field of disease research for its unique advantage in the disease molecular marker discovering Due to fewer adverse reactions and high safety, Chinese herbal medicine (CHM) has great advantages in the treatment of chronic diseases including depression. Metabolomics has been gradually applied to the efficacy evaluation of CHM in treatment of depression and the metabolomics analysis exhibits a systemic metabolic shift in amino acids (such as alanine, glutamic acid, valine, etc.), organic acids (lactic acid, citric acid, stearic acid, palmitic acid, etc.), and sugars, amines, etc. These differential metabolites are mainly involved in energy metabolism, amino acid metabolism, lipid metabolism, etc. In this review, we have exemplified the study of CHM in animals or clinics on the depression, and revealed that CHM treatment has significantly changed the metabolic disorders associated with depression, promoting metabolic network reorganization through restoring of key metabolites, and metabolic pathways, which may be the main mechanism basis of CHM's treatment on depression. Besides, we further envisioned the future application of metabolomics in the study of CHM treatment of depression.

Assessment of Phytochemicals and Herbal Formula for the Treatment of Depression through Metabolomics

Depression is a widespread and persistent psychiatric disease. Due to various side effects and no curative treatments of conventional antidepressant drugs, botanical medicines have attracted considerable attention as a complementary and alternative approach. The pathogenesis of depression is quite complicated and unclear. Metabolomics is a promising new technique for the discovery of novel biomarkers for exploring the potential mechanisms of diverse diseases and assessing the therapeutic effects of drugs. In this article, we systematically reviewed the study of botanical medicine for the treatment of depression using metabolomics over a period from 2010 to 2019. Additionally, we summarized the potential biomarkers and metabolic pathways associated with herbal medicine treatment for depression. Through a comprehensive evaluation of herbal medicine as novel antidepressants and understanding of their pharmacomechanisms, a new perspective on expanding the application of botanical medicines for the treatment of depression is provided.

Serum Metabolic Profiling Reveals the Antidepressive Effects of the Total Iridoids of Valeriana jatamansi Jones on Chronic Unpredictable Mild Stress Mice

Background

Depression is a long-term complex psychiatric disorder, and its etiology remains largely unknown. Valeriana jatamansi Jones ex Roxb (V. jatamansi) is used in the clinic for the treatment of depression, but there are insufficient reports of its antidepressive mechanisms and a poor understanding of its endogenous substance-related metabolism. The objective of this study was to identify biomarkers related to depression in serum samples and evaluate the antidepressive effects of the iridoid-rich fraction of V. jatamansi (IRFV) in a chronic unpredictable mild stress (CUMS) mouse model.

Methods

Here, CUMS was used to establish a mouse model of depression. Behavioral and biochemical indicators were investigated to evaluate the pharmacodynamic effects. A comprehensive serum metabolomics study by nuclear magnetic resonance (NMR) approach was applied to investigate the pharmacological mechanism of IRFV in CUMS mouse. Subsequently, we used multivariate statistical analysis to identify metabolic markers, such as principal component analysis (PCA) and orthogonal projection to latent structure with discriminant analysis (OPLS-DA), to distinguish between the CUMS mouse and the control group.

Results

After IRFV treatment, the immobility time, sucrose preference, and monoamine neurotransmitter were improved. PCA scores showed clear differences in metabolism between the CUMS group and control group. The PLS-DA or OPLS-DA model exhibited 26 metabolites as biomarkers to distinguish between the CUMS mice and the control mouse. Moreover, IRFV could significantly return 21 metabolites to normal levels.

Conclusion

The results confirmed that IRFV exerted an antidepressive effect by regulating multiple metabolic pathways, including the tricarboxylic acid cycle, the synthesis of neurotransmitters, and amino acid metabolism. These findings provide insights into the antidepressive mechanisms of IRFV.

Optimization of food deprivation and sucrose preference test in SD rat model undergoing chronic unpredictable mild stress

BACKGROUND

The chronic unpredictable mild stress (CUMS) model has long been considered the best model for exploring the pathophysiological mechanisms underlying depression. However, there are no widely recognised standards for strategies for modeling and for behavioral testing. The present study aimed to optimize the protocols for food deprivation and the sucrose preference test (SPT) for the CUMS model.

METHODS

We first evaluated the effects of different long periods of food deprivation on the body weight of Sprague Dawley (SD) rats by testing food deprivation for 24 hours (8:00-8:00+), food deprivation for 12 hours during the daytime (8:00-20:00) and food deprivation for 12 hours at night (20:00-8:00+). Next, we established a SD rat CUMS model with 15 different stimulations, and used body weight measurement, SPT, forced swim test (FST), open field test (OFT) and Morris water maze (MWM) test to verify the success of the modeling. In the SPT, consumption of sucrose and pure water within 1 and 12 hours was measured.

RESULTS

Twelve hours of food deprivation during the daytime (8:00-20:00) had no effect on body weight, while 12 hours of food deprivation at night (20:00-8:00+) and 24 hours of food deprivation (8:00-8:00+) significantly reduced the mean body weight of the SD rats. When SPT was used to verify the successful establishment of the CUMS rat model, sucrose consumption measured within 12 hours was less variable than that measured within 1 hour.

CONCLUSIONS

Twelve hours of food deprivation in the daytime (8:00-20:00) may be considered a mild stimulus for the establishment of a CUMS rat model. Measuring sucrose consumption over 12 hours is recommended for SPT.

Effects of Platycodins Folium on Depression in Mice Based on a UPLC-Q/TOF-MS Serum Assay and Hippocampus Metabolomics

Major depressive disorder (MDD), also known as depression, is a state characterized by low mood and aversion to activity. Platycodins Folium (PF) is the dried leaf of Platycodon grandiflorum, with anti-inflammatory and antioxidative activities. Our previous research suggested that PF was rich in flavonoids, phenols, organic acids, triterpenoid saponins, coumarins and terpenoids. This study aimed to investigate the antidepressant effect of PF using lipopolysaccharide (LPS)-induced depressive mice. Several behavior tests (sucrose preference test (SPT), forced swimming test (FST) and tail suspension test (TST)) and biochemical parameters (IL-6, TNF-α and SOD levels) were used to evaluate the antidepressive effect of PF on LPS-induced depression model. Furthermore, a UPLC-Q/TOF-MS-based metabolomics approach was applied to explore the latent mechanism of PF in attenuating depression. As a result, a total of 21 and 11 metabolites that potentially contribute to MDD progress and PF treatment were identified in serum and hippocampus, respectively. The analysis of metabolic pathways revealed that lipid metabolism, amino acid metabolism, energy metabolism, arachidonic acid metabolism, glutathione metabolism and inositol phosphate metabolism were disturbed in a model of mice undergoing MDD and PF treatment. These results help us to understand the pathogenesis of depression in depth, and to discover targets for clinical diagnosis and treatment. They also provide the possibility of developing PF into an anti-depressantive agent.

Metabolism, pharmacokinetics, and hepatic disposition of xanthones and saponins on Zhimu treatments for exploratively interpreting the discrepancy between the herbal safety and timosaponin A3-induced hepatotoxicity

Timosaponin A3, a saponin in Zhimu, elicited hepatotoxicity via oxidative stress. However, the clinical medication of Zhimu has been historically regarded as safe, probably associated with the antioxidants it contains. However, the related information on the in vivo levels of timosaponin A3 and antioxidants remained unclear on Zhimu treatments. Therefore, a combination of the in vitro metabolism, including microbiota-mediated and liver-mediated metabolism, and in vivo pharmacokinetics and hepatic disposition, was conducted for three xanthones (neomangiferin, mangiferin, and norathyriol) and three saponins (timosaponin B2, timosaponin B3, and timosaponin A3) on Zhimu treatments. Consequently, following oral administration of Zhimu decoction to rats, those saponins and xanthones were all observed in the plasma with severe liver first-pass effect, where mangiferin was of the maximum exposure. Despite the ignorable content in the herb, timosaponin A3 elicited sizable hepatic exposure as the microbiota-mediated metabolite of saponins in Zhimu. The similar phenomenon also occurred to norathyriol, the microbiota-mediated metabolite of xanthones. However, the major prototypes in Zhimu were of limited hepatic exposure. We deduced the hepatic collection of norathyriol, maximum circulating levels of mangiferin, and timosaponin B2 and mangiferin interaction may directly or indirectly contribute to the whole anti-oxidation of Zhimu, and then resisted the timosaponin A3-induced hepatotoxicity. Thus, our study exploratively interpreted the discrepancy between herbal safety and timosaponin A3-induced hepatotoxicity. However, given the considerable levels and slow eliminated rate of timosaponin A3 in the liver, more attention should be paid to the safety on the continuous clinical medication of Zhimu in the future.

Metabolic analysis of the antidepressive effects of Yangxinshi Tablet in a vascular depression model in mice

In recent years, vascular depression has become the focus of international attention. Yangxinshi Tablet (YXST) is usually used in cthe linic for the treatment of arrhythmia and heart failure, but we found that it also has antidepressive effects. The objective of the study was to identify biomarkers related to vascular depression in hippocampus and explore the antidepressive effects of YXST on the mouse model. Untargeted metabolomics based on UHPLC-Q-TOF/MS was applied to identify significantly differential biomarkers between the model group and control group. Unsupervised principal component analysis (PCA) was used to scan the tendency of groups and partial least squares-discriminant analysis (PLS-DA) to distinguish between the vascular depressive mice and the sham. PCA stores showed clear differences in metabolism between the vascular depressive mice and sham groups. The PLS-DA model exhibited 38 metabolites as the biomarkers to distinguish the vascular depressive mice and the sham. Further, YXST significantly regulated 22 metabolites to normal levels. The results suggested that YXST has a comprehensive antidepressive effect on vascular depression via regulation of multiple metabolic pathways including amino acid, the tricarboxylic acid cycle and phosphoglyceride metabolisms. These findings provide insight into the pathophysiological mechanism underlying vascular depression and the mechanism of YXST.