Fermentability of Maitake polysaccharides processed by various hydrothermal conditions and fermented with probiotic (Lactobacillus)

Maitake polysaccharides, after hydrothermal processing, were fermented with Lactobacillus acidophilus CCFM202 (L.A.) and Lactobacillus plantarum CCFM6392 (L.P.). The degradation of molecular weight of polysaccharides by hydrothermal processing under acidic conditions was obviously enhanced, which turned part of the water-insoluble-polysaccharides (WIP) into water-soluble-polysaccharides (WSPs). The pH value of water-soluble-polysaccharides (WSPs) and water-insoluble-polysaccharides (WIPs) were intensely dropped (4- 5) after 24 h fermentation. The optical density (O.D.) was increased (1.4- 2.3) due to bacterial growth, and short-chain fatty acids also followed this trend. LA-WSP predominantly produced acetic acid, 3- 4 folds to lactic acid, while LP-WIP groups produced dominant butyric acid (15- 17 folds). Hydrothermal processing induced the growth of L.A. and L.P., where the highest abundance was 2.5 × 10⁴. From the Venn diagram, WSP-1 produced the most elevated metabolites (874). Therefore, experimental results show a significant impact on making WSPs fragments, whereas temperature and pH influence the WSPs degradation, withstand to higher fermentation efficacy.

Diterpene Ginkgolides Exert an Antidepressant Effect Through the NT3-TrkA and Ras-MAPK Pathways

Background

Depression is a highly prevalent mental illness that severely impacts the quality of life of affected individuals. Our recent studies demonstrated that diterpene ginkgolides (DG) have antidepressant effects in mice. However, the underlying molecular mechanisms remained much unclear.

Methods

In this study, we assessed the antidepressant effects of chronic DG therapy in rats by evaluating depression-related behaviors, we also examined potential side effects using biochemical indicators. Furthermore, we performed an in-depth molecular network analysis of gene–protein–metabolite interactions on the basis of metabolomics.

Results

Chronic DG treatment significantly ameliorated the depressive-like behavioral phenotype. Furthermore, the neurotrophin signaling-related NT3-TrkA and Ras-MAPK pathways may play an important role in the antidepressant effect of DG in the hippocampus.

Conclusion

These findings provide novel insight into the mechanisms underlying the antidepressant action of DG, and should help advance the development of new therapeutic strategies for depression.

Metabolomics in Psychiatric Disorders: What We Learn from Animal Models

Biomarkers are a recent research target within biological factors of psychiatric disorders. There is growing evidence for deriving biomarkers within psychiatric disorders in serum or urine samples in humans, however, few studies have investigated this differentiation in brain or cerebral fluid samples in psychiatric disorders. As brain samples from humans are only available at autopsy, animal models are commonly applied to determine the pathogenesis of psychiatric diseases and to test treatment strategies. The aim of this review is to summarize studies on biomarkers in animal models for psychiatric disorders. For depression, anxiety and addiction disorders studies, biomarkers in animal brains are available. Furthermore, several studies have investigated psychiatric medication, e.g., antipsychotics, antidepressants, or mood stabilizers, in animals. The most notable changes in biomarkers in depressed animal models were related to the glutamate-γ-aminobutyric acid-glutamine-cycle. In anxiety models, alterations in amino acid and energy metabolism (i.e., mitochondrial regulation) were observed. Addicted animals showed several biomarkers according to the induced drugs. In summary, animal models provide some direct insights into the cellular metabolites that are produced during psychiatric processes. In addition, the influence on biomarkers due to short- or long-term medication is a noticeable finding. Further studies should combine representative animal models and human studies on cerebral fluid to improve insight into mental disorders and advance the development of novel treatment strategies.

Dl-3-n-butylphthalide attenuates mouse behavioral deficits to chronic social defeat stress by regulating energy metabolism via AKT/CREB signaling pathway

Major depressive disorder (MDD) is a severe mental disorder associated with high rates of morbidity and mortality. Current first-line pharmacotherapies for MDD are based on enhancement of monoaminergic neurotransmission, but these antidepressants are still insufficient and produce significant side-effects. Consequently, the development of novel antidepressants and therapeutic targets is desired. Dl-3-n-butylphthalide (NBP) is a compound with proven efficacy in treating ischemic stroke, yet its therapeutic effects and mechanisms for depression remain unexplored. The aim of this study was to investigate the effect of NBP in a chronic social defeat stress model of depression and its underlying molecular mechanisms. Here, we examined depression-related behavior and performed a targeted metabolomics analysis. Real-time quantitative polymerase chain reaction and western blotting were used to examine key genes and proteins involved in energy metabolism and the AKT/cAMP response element-binding protein (CREB) signaling pathway. Our results reveal NBP attenuates stress-induced social deficits, anxiety-like behavior and despair behavior, and alters metabolite levels of glycolysis and tricarboxylic acid (TCA) cycle components. NBP affected gene expression of key enzymes of the TCA cycle, as well as protein expression of p-AKT and p-CREB. Our findings provide the first evidence showing that NBP can attenuate stress-induced behavioral deficits by modulating energy metabolism by regulating activation of the AKT/CREB signaling pathway.

Hippocampal metabolic alteration in rat exhibited susceptibility to prenatal stress

BACKGROUND

Numerous studies have shown that prenatal stress (PS) can cause emotional and behavioral abnormalities including depression and depressive-like behaviors in offspring. However, the mechanism underlying the pathophysiology of depression remains largely unknown. In recent years, small metabolic molecules have played an increasingly important role in explaining the pathogenesis of depression. Thus, we detected hippocampal metabolic alteration in rat of depression caused by PS.

METHODS

To explore the potential molecular markers and pathways that link the metabolic to the pathogenesis of depression, we monitored changes in hippocampus metabolites during the development of depressive-like behaviors in rats exposed to PS via UHPLC-Q-TOF/MS approach. Sucrose preference test (SPT) was used to screen out the susceptibility rats exposed to PS, open field test (OFT), forced swimming test (FST) and tail suspension test (TST) were used to verify the validity of animal model of depression.

RESULTS

A total of 38 differential metabolites were detected in the susceptibility rats exposed to PS compared with that in controls. Most of these differential metabolites were related to Retrograde endocannabinoid signaling, Central carbon metabolism in cancer, Arginine biosynthesis, Choline metabolism in cancer, ABC transporters, Alanine, aspartate and glutamate metabolism pathways. In addition, the results of Spearman correlation analysis indicated that L-aspartate, N-Acetylaspartylglutamate, choline and betaine aldehyde were most associated with depressive-like behaviors.

CONCLUSION

This study demonstrates that hippocampal metabolites in the Alanine, aspartate and glutamate metabolism pathways may play a crucial role in the depressive-like behaviors.

Absence of gut microbiota affects lipid metabolism in the prefrontal cortex of mice

Objectives: Lipid metabolism is closely associated with many important biological functions. Here, we conducted this study to explore the effects of gut microbiota on the lipid metabolism in the prefrontal cortex of mice. Methods: Germ-free (GF) mice, specific pathogen-free (SPF) and colonized GF (CGF) mice were used in this study. The open field test (OFT), forced swimming test (FST) and novelty suppressed feeding test (NSFT) were conducted to assess the changes in general behavioral activity. The liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) was used to obtain the lipid metabolites. Both one-way analysis of variance (one-way ANOVA) and orthogonal partial least-squares discriminant analysis (OPLS-DA) were used to obtain the key differential lipid metabolites. Results: The behavioral tests showed that compared to SPF mice, GF mice had more center distance, more center time, less immobility time and less latency to familiar food. Meanwhile, 142 key differential lipid metabolites between SPF mice and GF mice were identified. These lipid metabolites mainly belonged to glycerophospholipids, glycerolipids, sphingolipids, and saccharolipids. The gut microbiota colonization did not reverse these changed behavioral phenotypes, but could restore 25 key differential lipid metabolites. Discussion: These results showed that the absence of gut microbiota could influence host behaviors and lipid metabolism. Our findings could provide original and valuable data for future studies to further investigate the microbiota-gut-brain axis.

Urinary biomarker panel for diagnosing patients with depression and anxiety disorders

Available data indicate that patients with depression and anxiety disorders are likely to be at greater risk for suicide. Therefore, it is important to correctly diagnose patients with depression and anxiety disorders. However, there are still no empirical laboratory methods to objectively diagnose these patients. In this study, the multiple metabolomics platforms were used to profile the urine samples from 32 healthy controls and 32 patients with depression and anxiety disorders for identifying differential metabolites and potential biomarkers. Then, 16 healthy controls and 16 patients with depression and anxiety disorders were used to independently validate the diagnostic performance of the identified biomarkers. Finally, a panel consisting of four biomarkers-N-methylnicotinamide, aminomalonic acid, azelaic acid and hippuric acid-was identified. This panel was capable of distinguishing patients with depression and anxiety disorders from healthy controls with an area under the receiver operating characteristic curve of 0.977 in the training set and 0.934 in the testing set. Meanwhile, we found that these identified differential metabolites were mainly involved in three metabolic pathways and five molecular and cellular functions. Our results could lay the groundwork for future developing a urine-based diagnostic method for patients with depression and anxiety disorders.