Deficiency in the Essential Amino Acids l-Isoleucine, l-Leucine and l-Histidine and Clinical Measures as Predictors of Moderate Depression in Elderly Women: A Discriminant Analysis Study

Microbiota-mediated metabolic perturbations in the gut and brain of mice after microplastic exposure

Microplastics (MPs), emerging environmental toxicants, have drawn attention because of their wide distribution in the environment. Exposure to MPs induces gut microbiota dysbiosis, intestinal barrier dysfunction, metabolic perturbations, and neurotoxicity in different rodents. However, the relationship between MPs, gut microbiota, and the metabolome of the gut and brain in mice remains unclear. In this study, female C57BL/6 mice were orally gavaged with vehicle, 200 nm MP, and 800 nm MP three times per week for four weeks. Cecal contents were collected for gut microbiota analysis using 16S rRNA gene sequencing. Intestinal and brain tissues from mice were used to determine metabolic profiles using liquid chromatography-mass spectrometry (LC-MS). The results showed that MP altered microbiota composition, accompanied by metabolic perturbations in the mouse gut and brain. Specifically, Firmicutes and Bacteroidetes were suggested to be important phyla for MP exposure, partially dominating further metabolite alterations. Simultaneously, MP-induced metabolic profiles were associated with energy homeostasis and bile acid, nucleotide, and carnitine metabolic pathways. The results of the mediation analysis further revealed an MP-microbiota-metabolite relationship. Our results indicate that MPs can induce gut dysbiosis and disturb metabolic dysfunction in the mouse brain and/or intestine. Integrative omics approaches have the potential to monitor MP-induced molecular responses in various organs and systematically elucidate the complex mechanisms of human health effects.

Assessing the risk of prenatal depressive symptoms in Chinese women: an integrated evaluation of serum metabolome, multivitamin supplement intake, and clinical blood indicators

Background

Prenatal depressive symptoms (PDS) is a serious public health problem. This study aimed to develop an integrated panel and nomogram to assess at-risk populations by examining the association of PDS with the serum metabolome, multivitamin supplement intake, and clinical blood indicators.

Methods

This study comprised 221 pregnant women, categorized into PDS and non-PDS groups based on the Edinburgh postnatal depression scale. The participants were divided into training and test sets according to their enrollment time. We conducted logistic regression analysis to identify risk factors, and employed liquid chromatography/high resolution mass spectrometry-based serum metabolome analysis to identify metabolic biomarkers. Multiple factor analysis was used to combine risk factors, clinical blood indicators and key metabolites, and then a nomogram was developed to estimate the probability of PDS.

Results

We identified 36 important differential serum metabolites as PDS biomarkers, mainly involved in amino acid metabolism and lipid metabolism. Multivitamin intake works as a protective factor for PDS. The nomogram model, including multivitamin intake, HDL-C and three key metabolites (histidine, estrone and valylasparagine), exhibited an AUC of 0.855 in the training set and 0.774 in the test set, and the calibration curves showed good agreement, indicating that the model had good stability.

Conclusion

Our approach integrates multiple models to identify metabolic biomarkers for PDS, ensuring their robustness. Furthermore, the inclusion of dietary factors and clinical blood indicators allows for a comprehensive characterization of each participant. The analysis culminated in an intuitive nomogram based on multimodal data, displaying potential performance in initial PDS risk assessment.

Exploring the human gut microbiota targets in relation to the use of contemporary antidepressants

BACKGROUND

Antidepressants, specifically selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), are commonly prescribed for depression treatment. Animal studies have shown that antidepressants can influence gut microbiota composition and specific bacterial taxa. We aimed to investigate the association between antidepressant use and human gut microbiota composition and functional pathway.

METHODS

We collected information on antidepressant use, demographic, food patterns, and clinical characteristics through questionnaires and medical records. The gut microbiota profiles of 271 depressive patients were carried out through 16S rRNA gene sequencing. Patients were categorized based on different types of antidepressant use groups for gut microbiota comparisons. MaAsLin2 was performed to evaluate microbiota composition across groups. PICRUSt2 was used to predict microbiota functional pathways.

RESULTS

Patients taking SSRIs or SNRIs had a lower microbiota diversity. We found seven taxa abundances (Turicibacter, Barnesiella, Lachnospiraceae_ND3007_group, Romboutia, Akkermansia, Dialister, Romboutia and Fusicatenibacter) differed in patients with various types of antidepressants compared with those without antidepressant treatments (p < 0.05). Turicibacter inversely correlated with depression severity in SSRIs or SNRI users (r = -0.43, p < 0.05). Top identified pathways were related to compound fermentation and biosynthesis in microbiota function.

CONCLUSION

Antidepressant usage, especially SSRIs and SNRIs, associates with changes in gut microbiota composition and specific taxa. Given our study's preliminary cross-sectional nature, further research is warranted to comprehend the relationship between antidepressant use, treatment response, and gut microbiota, aiming to enhance therapeutic interventions in the future.

Metabolome subtyping reveals multi-omics characteristics and biological heterogeneity in major psychiatric disorders

Growing evidence suggests that major psychiatric disorders (MPDs) share common etiologies and pathological processes. However, the diagnosis is currently based on descriptive symptoms, which ignores the underlying pathogenesis and hinders the development of clinical treatments. This highlights the urgency of characterizing molecular biomarkers and establishing objective diagnoses of MPDs. Here, we collected untargeted metabolomics, proteomics and DNA methylation data of 327 patients with MPDs, 131 individuals with genetic high risk and 146 healthy controls to explore the multi-omics characteristics of MPDs. First, differential metabolites (DMs) were identified and we classified MPD patients into 3 subtypes based on DMs. The subtypes showed distinct metabolomics, proteomics and DNA methylation signatures. Specifically, one subtype showed dysregulation of complement and coagulation proteins, while the DNA methylation showed abnormalities in chemical synapses and autophagy. Integrative analysis in metabolic pathways identified the important roles of the citrate cycle, sphingolipid metabolism and amino acid metabolism. Finally, we constructed prediction models based on the metabolites and proteomics that successfully captured the risks of MPD patients. Our study established molecular subtypes of MPDs and elucidated their biological heterogeneity through a multi-omics investigation. These results facilitate the understanding of pathological mechanisms and promote the diagnosis and prevention of MPDs.

Imbalance of multiple neurotransmitter pathways leading to depression-like behavior and cognitive dysfunction in the triple transgenic mouse model of Alzheimer disease

Depression is among the most frequent psychiatric comorbid conditions in Alzheimer disease (AD). However, pharmacotherapy for depressive disorders in AD is still a big challenge, and the data on the efffcacy of current antidepressants used clinically for depressive symptoms in patients with AD remain inconclusive. Here we investigated the mechanism of the interactions between depression and AD, which we believe would aid in the development of pharmacological therapeutics for the comorbidity of depression and AD. Female APP/PS1/Tau triple transgenic (3×Tg-AD) mice at 24 months of age and age- and sex-matched wild-type (WT) mice were used. The shuttle-box passive avoidance test (PAT) were implemented to assess the abilities of learning and memory, and the open field test (OFT) and the tail suspension test (TST) were used to assess depression-like behavior. High-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was used to detect the level of neurotransmitters related to depression in the hippocampus of mice. The data was identified by orthogonal projections to latent structures discriminant analysis (OPLS-DA). Most neurotransmitters exert their effects by binding to the corresponding receptor, so the expression of relative receptors in the hippocampus of mice was detected using Western blot. Compared to WT mice, 3×Tg-AD mice displayed significant cognitive impairment in the PAT and depression-like behavior in the OFT and TST. They also showed significant decreases in the levels of L-tyrosine, norepinephrine, vanillylmandelic acid, 5-hydroxytryptamine, and acetylcholine, in contrast to significant increases in 5-hydroxyindoleacetic acid, L-histidine, L-glutamine, and L-arginine in the hippocampus. Moreover, the expression of the alpha 1a adrenergic receptor (ADRA1A), serotonin 1 A receptor (5HT1A), and γ-aminobutyric acid A receptor subunit alpha-2 (GABRA2) was significantly downregulated in the hippocampus of 3×Tg-AD mice, while histamine H3 receptor (H3R) expression was significantly upregulated. In addition, the ratio of phosphorylated cAMP-response element-binding protein (pCREB) and CREB was significantly decreased in the hippocampus of 3×Tg-AD mice than WT mice. We demonstrated in the present study that aged female 3×Tg-AD mice showed depression-like behavior accompanied with cognitive dysfunction. The complex and diverse mechanism appears not only relevant to the imbalance of multiple neurotransmitter pathways, including the transmitters and receptors of the monoaminergic, GABAergic, histaminergic, and cholinergic systems, but also related to the changes in L-arginine and CREB signaling molecules.

Effect of Probiotic Yogurt Supplementation(Bifidobacterium animalis ssp. lactis BB-12) on Gut Microbiota of Female Taekwondo Athletes and Its Relationship with Exercise-Related Psychological Fatigue

OBJECTIVE

The gut microbiota plays a critical role in regulating human health and athletic performance. Probiotic supplementation has been shown to modulate gut microbiota composition and improve exercise performance. This study aimed to investigate the effect of probiotic yogurt supplementation on gut microbiota and its relationship with exercise-related psychological fatigue in female taekwondo athletes.

METHODS

Twenty female taekwondo athletes were randomly assigned to either a dietary intervention group (DK) or a control group (CK). The athletes' exercise-related psychological fatigue was measured using the Athlete Burnout Questionnaire (ABQ) before and after an 8-week intervention. High-throughput sequencing was used to profile the gut microbiota, and functional prediction of the microbial community was performed. The effect of the dietary intervention on the athletes' exercise-related psychological fatigue clearance rate and its relationship with the gut microbiota were explored.

RESULTS

(1) The probiotic supplementation of Bifidobacterium animalis ssp. lactis BB-12 for 8 weeks significantly increased the ABQ scores of the DK group compared to the CK group (p < 0.05). (2) The abundances of Bifidobacterium, Bacteroides, Lachnospiraceae, family _Lactobacillaceae, and genus _Lactobacillus were significantly higher in the DK group than in the CK group after probiotic supplementation, while Escherichia coli was significantly lower in the DK group than in the CK group. (3) The ABQa scores were positively correlated with Proteus; ABQb scores were positively correlated with Streptococcus and Enterococcus; and ABQc scores were positively correlated with Klebsiella, Bacteroides, and Streptomyces. (4) The DK group had significantly higher levels of L-arginine biosynthesis I (via L-ornithine), fatty acid biosynthesis and oxidation, and L-isoleucine biosynthesis III pathways compared to the CK group. Tyrosine degradation I (via 2,3-dihydroxyphenylpropionate) was significantly lower in the DK group than in the CK group.

CONCLUSIONS

Probiotic yogurt supplementation of Bifidobacterium animalis ssp. lactis can promote the clearance of exercise-related psychological fatigue in female taekwondo athletes by upregulating beneficial gut microbiota, inhibiting harmful gut microbiota, and regulating relevant metabolic pathways.

Alteration of the gut microbiome and correlated metabolism in a rat model of long-term depression

Objective

This study aims to investigate the composition and function of the gut microbiome in long-term depression using an 8-week chronic unpredictable mild stress (CUMS) rat model.

Materials and methods

Animals were sacrificed after either 4 weeks or 8 weeks under CUMS to mimic long-term depression in humans. The gut microbiome was analyzed to identify potential depression-related gut microbes, and the fecal metabolome was analyzed to detect their functional metabolites. The correlations between altered gut microbes and metabolites in the long-term depression rats were explored. The crucial metabolic pathways related to long-term depression were uncovered through enrichment analysis based on these gut microbes and metabolites.

Results

The microbial composition of long-term depression (8-week CUMS) showed decreased species richness indices and different profiles compared with the control group and the 4-week CUMS group, characterized by disturbance of Alistipes indistinctus, Bacteroides ovatus, and Alistipes senegalensis at the species level. Additionally, long-term depression was associated with disturbances in fecal metabolomics. D-pinitol was the only increased metabolite in the 8-week CUMS group among the top 10 differential metabolites, while the top 3 decreased metabolites in the long-term depression rats included indoxyl sulfate, trimethylaminen-oxide, and 3 alpha,7 alpha-dihydroxy-12-oxocholanoic acid. The disordered fecal metabolomics in the long-term depression rats mainly involved the biosynthesis of pantothenate, CoA, valine, leucine and isoleucine.

Conclusion

Our findings suggest that the gut microbiome may participate in the long-term development of depression, and the mechanism may be related to the regulation of gut metabolism.

Free amino acids identification and process optimization in greengage wine fermentation and flavor formation

Greengage wine with low alcohol content is increasing in popularity owing to its fruity taste and rich nutrition. The key to wine aroma and taste is flavor substances like free amino acids (FAAs), volatile fatty acids, higher alcohols, and esters. Amino acid (AA) metabolisms in yeast are an important source of these secondary compounds, which vary with the fermentation conditions. This study explored and optimized the impact of different parameters (carbon source, inoculum, pH, temperature) on FAA contents and dynamics in greengage wine. The results demonstrated that total and essential amino acid (EAA) content rose with a higher proportion of glucose, less yeast inoculation, higher temperature, and higher initial pH. With the results obtained it was concluded that the condition of 22.4°C, pH 4.5, and 3% inoculation was optimum for a 14.9-fold increase of EAAs in fermented greengage wine. In the long run, the research will aid in the development of the greengage brewing industry.

Differences in peripheral and central metabolites and gut microbiome of laying hens with different feather-pecking phenotypes

Background

Feather pecking (FP) is a maladaptive behavior in laying hens that is associated with numerous physiological traits, including those involving the central neurotransmitter system and the immune system, which have been identified in many species as being regulated by the gut microbiota via the "microbiota-gut-brain" (MGB) axis. Yet, it is unknown whether and how gut microbiota influences FP by regulating multiple central neurotransmission systems and immune system.

Methods

This study was measured the prevalence of severe FP (SFP) in the commercial layer farm. The chicken flock with the highest frequency of SFP were selected for FP phenotype identification. Nontargeted metabolomics was performed to investigated the differences in the peripheral and central metabolites and 16S rDNA sequencing was performed to investigated the differences in gut microbiome of laying hens with different FP phenotypes. Correlation analysis was performed to determine the potential mechanism by which the disturbed gut microbiota may modulate host physiology and behavior.

Results

The results showed that pullets (12 weeks of age) showed significantly higher SFP frequencies than chicks (6 weeks of age) and adults (22 weeks of age; p < 0.05). Compared to neutrals (N), peckers (P) exhibited the stress-induced immunosuppression with the increased plasma levels of corticosterone and norepinephrine, and the decreased plasma levels of IgA, IL-1, IL-6 and tumor necrosis factor α (p < 0.05). In the cecum, the relative abundances of Bacteroides and Gemmiger were higher in the P group, while Roseburia, Ruminococcus2, Anaerostipes, Lachnospiracea_incertae_sedis and Methanobrevibacter were more enriched in the N group. Moreover, increased plasma levels of L-tryptophan, beta-tyrosine and L-histidine were found in the P group (p < 0.05). Notably, in the P group, hippocampal levels of L-tryptophan, xanthurenic acid, L-histidine and histamine were improved and showed a positive association with L-glutamic acid levels. Plasma levels of L-tryptophan, beta-tyrosine and L-histidine were both positively correlated with Bacteroides abundance but negatively correlated with Methanobrevibacter abundance.

Conclusion

Overall, these findings suggest that the development of FP may be affected by the gut microbiota, which regulates the central glutamatergic nerve system by altering the metabolism of tryptophan, histidine and tyrosine.

Late-life depression: Epidemiology, phenotype, pathogenesis and treatment before and during the COVID-19 pandemic

Late-life depression (LLD) is one of the most common mental disorders among the older adults. Population aging, social stress, and the COVID-19 pandemic have significantly affected the emotional health of older adults, resulting in a worldwide prevalence of LLD. The clinical phenotypes between LLD and adult depression differ in terms of symptoms, comorbid physical diseases, and coexisting cognitive impairments. Many pathological factors such as the imbalance of neurotransmitters, a decrease in neurotrophic factors, an increase in β-amyloid production, dysregulation of the hypothalamic-pituitary-adrenal axis, and changes in the gut microbiota, are allegedly associated with the onset of LLD. However, the exact pathogenic mechanism underlying LLD remains unclear. Traditional selective serotonin reuptake inhibitor therapy results in poor responsiveness and side effects during LLD treatment. Neuromodulation therapies and complementary and integrative therapies have been proven safe and effective for the treatment of LLD. Importantly, during the COVID-19 pandemic, modern digital health intervention technologies, including socially assistive robots and app-based interventions, have proven to be advantageous in providing personal services to patients with LLD.

The PROVIT Study-Effects of Multispecies Probiotic Add-on Treatment on Metabolomics in Major Depressive Disorder-A Randomized, Placebo-Controlled Trial

The gut–brain axis plays a role in major depressive disorder (MDD). Gut-bacterial metabolites are suspected to reduce low-grade inflammation and influence brain function. Nevertheless, randomized, placebo-controlled probiotic intervention studies investigating metabolomic changes in patients with MDD are scarce. The PROVIT study (registered at clinicaltrials.com NCT03300440) aims to close this scientific gap. PROVIT was conducted as a randomized, single-center, double-blind, placebo-controlled multispecies probiotic intervention study in individuals with MDD (n = 57). In addition to clinical assessments, metabolomics analyses (1H Nuclear Magnetic Resonance Spectroscopy) of stool and serum, and microbiome analyses (16S rRNA sequencing) were performed. After 4 weeks of probiotic add-on therapy, no significant changes in serum samples were observed, whereas the probiotic groups’ (n = 28) stool metabolome shifted towards significantly higher concentrations of butyrate, alanine, valine, isoleucine, sarcosine, methylamine, and lysine. Gallic acid was significantly decreased in the probiotic group. In contrast, and as expected, no significant changes resulted in the stool metabolome of the placebo group. Strong correlations between bacterial species and significantly altered stool metabolites were obtained. In summary, the treatment with multispecies probiotics affects the stool metabolomic profile in patients with MDD, which sets the foundation for further elucidation of the mechanistic impact of probiotics on depression.