Gut Microbiota Mediates the Preventive Effects of Dietary Capsaicin Against Depression-Like Behavior Induced by Lipopolysaccharide in Mice

The protective effect of S-adenosylmethionine on chronic adolescent stress-induced depression-like behaviors by regulating gut microbiota

The efficacy and tolerability of current antidepressants for adolescent depression are inadequate. S-adenosylmethionine (SAMe), known for its effectiveness and minimal side effects in adult depression, remains unstudied in adolescents. This study explored the potential of SAMe to address depression-like behaviors in juvenile rats induced by chronic unpredictable mild stress (CUMS), with a focus on gut microbiome interactions. Adolescent male Wistar rats were subjected to a 4-week CUMS regimen and received daily intraperitoneal injections of 300 mg/kg SAMe. Behavioral assessments included the sucrose preference test, elevated plus maze test, open field test, and Y-maze test. Histopathological changes of the hippocampus and colon were observed by Nissl staining and hematoxylin and eosin staining, respectively. Gut microbiome composition was analyzed using Accurate 16S absolute quantification sequencing. The results showed that SAMe significantly improved behavioral outcomes, reduced histopathological damages in hippocampal neurons and colon tissues, and modulated the gut microbiota of depressed rats. It favorably altered the ratio of Bacteroidetes to Firmicutes, decreased the absolute abundance of Deferribacteres, and adjusted levels of key microbial genera associated with depression-like behaviors. These results suggested that SAMe could effectively counter depression-like behaviors in CUMS-exposed adolescent rats by mitigating hippocampal neuronal and colon damage and modulating the gut microbiota. This supports SAMe as a viable and tolerable treatment option for adolescent depression, highlighting the importance of the gut-brain axis in therapeutic strategies.

Microbiota-gut-brain axis: Natural antidepressants molecular mechanism

BACKGROUND

Major depressive disorder (MDD) is a severe mental health condition characterized by persistent depression, impaired cognition, and reduced activity. Increasing evidence suggests that gut microbiota (GM) imbalance is closely linked to the emergence and advancement of MDD, highlighting the potential significance of regulating the "Microbiota-Gut-Brain" (MGB) axis to impact the development of MDD. Natural products (NPs), characterized by broad biological activities, low toxicity, and multi-target characteristics, offer unique advantages in antidepressant treatment by regulating MGB axis.

PURPOSE

This review was aimed to explore the intricate relationship between the GM and the brain, as well as host responses, and investigated the mechanisms underlying the MGB axis in MDD development. It also explored the pharmacological mechanisms by which NPs modulate MGB axis to exert antidepressant effects and addressed current research limitations. Additionally, it proposed new strategies for future preclinical and clinical applications in the MDD domain.

METHODS

To study the effects and mechanism by which NPs exert antidepressant effects through mediating the MGB axis, data were collected from Web of Science, PubMed, ScienceDirect from initial establishment to March 2024. NPs were classified and summarized by their mechanisms of action.

RESULTS

NPs, such as flavonoids,alkaloids,polysaccharides,saponins, terpenoids, can treat MDD by regulating the MGB axis. Its mechanism includes balancing GM, regulating metabolites and neurotransmitters such as SCAFs, 5-HT, BDNF, inhibiting neuroinflammation, improving neural plasticity, and increasing neurogenesis.

CONCLUSIONS

NPs display good antidepressant effects, and have potential value for clinical application in the prevention and treatment of MDD by regulating the MGB axis. However, in-depth study of the mechanisms by which antidepressant medications affect MGB axis will also require considerable effort in clinical and preclinical research, which is essential for the development of effective antidepressant treatments.

Antidepressant effect of carvedilol on streptozotocin-induced diabetic peripheral neuropathy mice by altering gut microbiota

RATIONALE

Although diabetic peripheral neuropathic pain (DPNP) and depression have been recognized for many years, their co-morbidity relationship and effective treatment choices remain uncertain.

OBJECTIVES

To evaluate the antidepressant effect of carvedilol on streptozotocin-induced DPNP mice, and the relationship with gut microbiota.

METHODS

The hyperalgesia and depressive behaviors of mice with comorbidity of DPNP and depression were confirmed by pain threshold of the mechanical sensitivity test (MST), immobility time of the tail suspension test (TST) and the forced swimming test (FST). The anti-depressive effect and fecal gut microbiota composition were studied in DPNP mice treated with carvedilol (10 mg/kg/day), and the relationships between them were analyzed by Spearman's correlation.

RESULTS

Depression was successfully induced in DPNP mice. Carvedilol can reverse the decreased mechanical pain threshold and relieve the depressive behaviors of DPNP mice, while increasing the abundance of Prevotella, Ruminococcus, Helicobacter and Desulfovibrio, and decreasing the abundance of Akkermansia and Allobaculum.

CONCLUSIONS

Carvedilol can alleviate the mechanical hyperalgesia and alter gut microbiota to ameliorate the depression-like behaviors which induced by DPNP.

Capsaicin Modulates Hepatic and Intestinal Inflammation and Oxidative Stress by Regulating the Colon Microbiota

We aimed to investigate the role of capsaicin (CAP) in modulating lipopolysaccharide (LPS)-induced hepatic and intestinal inflammation, oxidative stress, and its colonic microflora in mice. Thirty healthy male Kunming mice with similar body weights were randomly assigned to three groups: the control group (CON), the LPS group, and the CAP group, with ten mice in each group. The CON and the LPS groups received a daily dose of normal saline, respectively, while the CAP group received an equivalent dose of CAP. On the 28th day of the experiment, the LPS and the CAP groups were intraperitoneally injected with LPS, while the CON group was injected with an equal volume of normal saline. The results lead to the following conclusions. Compared to the LPS group, CAP improved the loss of hepatic lobular structure and significantly increased the duodenal villus length and ratio of villus length to crypt depth. CAP increased hepatic and colon interleukin-10 (IL-10) and decreased IL-6, IL-1β, and tumor necrosis factor (TNF-α) levels. CAP also increased hepatic catalase (CAT), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) expression, and decreased malondialdehyde (MDA) levels. CAP significantly increased the relative abundances of Mucispirillum, Helicobacter, Prevotellaceae-UCG-001, Colidextribacter, unclassified-f-Oscillospiraceae, and Odoribacter, some of which were closely related to hepatic and colonic immune and oxidative markers. CAP also decreased the overall content of short-chain fatty acids, except for propionic acid. Overall, CAP can regulate the colon microbiota and exert anti-inflammatory and antioxidant effects. Whether CAP exerts its anti-inflammatory and antioxidant effects by modulating the colonic microflora, mainly Mucispirillum spp. and Helicobacter spp., requires further investigation.

Multiple effects of spicy flavors on neurological diseases through the intervention of TRPV1: a critical review

The spicy properties of foods are contributed by various spicy flavor substances (SFs) such as capsaicin, piperine, and allicin. Beyond their distinctive sensory characteristics, SFs also influence health conditions and numerous studies have associated spicy flavors with disease treatment. In this review, we enumerate different types of SFs and describe their role in food processing, with a specific emphasis on critically examining their influence on human wellness. Particularly, detailed insights into the mechanisms through which SFs enhance physiological balance and alleviate neurological diseases are provided, and a systematic analysis of the significance of transient receptor potential vanilloid type-1 (TRPV1) in regulating metabolism and nervous system homeostasis is presented. Moreover, enhancing the accessibility and utilization of SFs can potentially amplify the physiological effects. This review aims to provide compelling evidence for the integration of food flavor and human health.

Deciphering Microbiome, Transcriptome, and Metabolic Interactions in the Presence of Probiotic Lactobacillus acidophilus against Salmonella Typhimurium in a Murine Model

Salmonella enterica serovar Typhimurium (S. Typhimurium), a foodborne pathogen that poses significant public health risks to humans and animals, presents a formidable challenge due to its antibiotic resistance. This study explores the potential of Lactobacillus acidophilus (L. acidophilus 1.3251) probiotics as an alternative strategy to combat antibiotic resistance associated with S. Typhimurium infection. In this investigation, twenty-four BALB/c mice were assigned to four groups: a non-infected, non-treated group (CNG); an infected, non-treated group (CPG); a group fed with L. acidophilus but not infected (LAG); and a group fed with L. acidophilus and challenged with Salmonella (LAST). The results revealed a reduction in Salmonella levels in the feces of mice, along with restored weight and improved overall health in the LAST compared to the CPG. The feeding of L. acidophilus was found to downregulate pro-inflammatory cytokine mRNA induced by Salmonella while upregulating anti-inflammatory cytokines. Additionally, it influenced the expression of mRNA transcript, encoding tight junction protein, oxidative stress-induced enzymes, and apoptosis-related mRNA expression. Furthermore, the LEfSe analysis demonstrated a significant shift in the abundance of critical commensal genera in the LAST, essential for maintaining gut homeostasis, metabolic reactions, anti-inflammatory responses, and butyrate production. Transcriptomic analysis revealed 2173 upregulated and 506 downregulated differentially expressed genes (DEGs) in the LAST vs. the CPG. Functional analysis of these DEGs highlighted their involvement in immunity, metabolism, and cellular development. Kyoto Encyclopedia of Genes and Genome (KEGG) pathway analysis indicated their role in tumor necrosis factor (TNF), mitogen-activated protein kinase (MAPK), chemokine, Forkhead box O (FOXO), and transforming growth factor (TGF-β) signaling pathway. Moreover, the fecal metabolomic analysis identified 929 differential metabolites, with enrichment observed in valine, leucine, isoleucine, taurine, glycine, and other metabolites. These findings suggest that supplementation with L. acidophilus promotes the growth of beneficial commensal genera while mitigating Salmonella-induced intestinal disruption by modulating immunity, gut homeostasis, gut barrier integrity, and metabolism.

Neuroprotective effects of probiotics on anxiety- and depression-like disorders in stressed mice by modulating tryptophan metabolism and the gut microbiota

Anxiety- and depression-like behaviors are commonly observed clinical features of depression and many other mental disorders. Recent evidence has revealed the crucial role of the microbiota-gut-brain axis in the bidirectional communication between the gastrointestinal tract and the central nervous system. Supplementation with psychobiotics may provide a novel approach for the adjunctive treatment of mental disorders by regulating the intestinal microecology. We isolated and identified a novel probiotic, Lactiplantibacillus plantarum D-9 (D-9), from traditional Chinese fermented foods in our previous work, which exhibited a high yield of gamma-aminobutyric acid (GABA). Herein, it was proved that the oral administration of D-9 could alleviate the depression- and anxiety-like behaviors of Chronic Unpredicted Mild Stress (CUMS) mice, and show non-toxicity or side-effects in the mice. Physiological and biochemical analyses demonstrated that D-9 regulated tryptophan metabolism, the HPA-axis and inflammation in CUMS mice. Moreover, D-9 modulated the structure and composition of the gut microbiota, leading to an increase in the relative abundance of Ligilactobacillus murinus and Lactobacillus johnsonii, and a decrease in the levels of Kineothrix alysoides and Helicobacter bilis compared to those in CUMS mice. Our work demonstrates that D-9 alleviated anxiety- and depression-like disorders in CUMS mice by modulating tryptophan metabolism and the gut microbiota. These findings provide an innovative strategy for the intervention and treatment of depressive disorders.

Integrating network pharmacology with molecular docking to rationalize the ethnomedicinal use of Alchornea laxiflora (Benth.) Pax & K. Hoffm. for efficient treatment of depression

Background: Alchornea laxiflora (Benth.) Pax & K. Hoffm. (A. laxiflora) has been indicated in traditional medicine to treat depression. However, scientific rationalization is still lacking. Hence, this study aimed to investigate the antidepressant potential of A. laxiflora using network pharmacology and molecular docking analysis. Materials and methods: The active compounds and potential targets of A. laxiflora and depression-related targets were retrieved from public databases, such as PubMed, PubChem, DisGeNET, GeneCards, OMIM, SwissTargetprediction, BindingDB, STRING, and DAVID. Essential bioactive compounds, potential targets, and signaling pathways were predicted using in silico analysis, including BA-TAR, PPI, BA-TAR-PATH network construction, and GO and KEGG pathway enrichment analysis. Later on, with molecular docking analysis, the interaction of essential bioactive compounds of A. laxiflora and predicted core targets of depression were verified. Results: The network pharmacology approach identified 15 active compounds, a total of 219 compound-related targets, and 14,574 depression-related targets with 200 intersecting targets between them. SRC, EGFR, PIK3R1, AKT1, and MAPK1 were the core targets, whereas 3-acetyloleanolic acid and 3-acetylursolic acid were the most active compounds of A. laxiflora with anti-depressant potential. GO functional enrichment analysis revealed 129 GO terms, including 82 biological processes, 14 cellular components, and 34 molecular function terms. KEGG pathway enrichment analysis yielded significantly enriched 108 signaling pathways. Out of them, PI3K-Akt and MAPK signaling pathways might have a key role in treating depression. Molecular docking analysis results exhibited that core targets of depression, such as SRC, EGFR, PIK3R1, AKT1, and MAPK1, bind stably with the analyzed bioactive compounds of A. laxiflora. Conclusion: The present study elucidates the bioactive compounds, potential targets, and pertinent mechanism of action of A. laxiflora in treating depression. A. laxiflora might exert an antidepressant effect by regulating PI3K-Akt and MAPK signaling pathways. However, further investigations are required to validate.

UHPLC-qTOF-MS-Based Nontargeted Metabolomics to Characterize the Effects of Capsaicin on Plasma and Skin Metabolic Profiles of C57BL/6 Mice-An In vivo Experimental Study

Background

Capsaicin is the main compound found in chili pepper and has complex pharmacologic effects. This study aimed to elucidate the mechanism of the effect of capsaicin on physiological processes by analyzing changes in metabolites and metabolic pathways.

Methods

Female C57BL/6 mice were divided into two groups(n = 10/group) and fed with capsaicin-soybean oil solution(group T) or soybean oil(group C) for 6 weeks. Ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC-qTOF-MS) based metabolomics was undertaken to assess plasma and skin metabolic profile changes and identify differential metabolites through multivariate analysis.

Results

According to the OPLS-DA score plots, the plasma and skin metabolic profiles in the group T and group C were significantly separated. In plasma, 38 significant differential metabolites were identified. KEGG pathway enrichment analysis revealed that the most significant plasma metabolic pathways included pyruvate metabolism and ABC transporters. In skin, seven significant differential metabolites were found. Four metabolic pathways with p values < 0.05 were detected, including sphingolipid metabolism, sphingolipid signaling pathway, apoptosis, and necroptosis.

Conclusion

These findings will provide metabolomic insights to assess the physiological functions of capsaicin and contribute to a better understanding of the potential effects of a capsaicin-rich diet on health.

Alzheimer, Parkinson, dementia, and phytochemicals: insight review

Alzheimer's, Parkinson's, and dementia are the leading neurodegenerative diseases that threaten the world with the aging population. Although the pathophysiology of each disease is unique, the steps to be taken to prevent diseases are similar. One of the changes that a person can make alone is to gain the habit of an antioxidant-rich diet. Phytochemicals known for their antioxidant properties have been reported to prevent neurodegenerative diseases in various studies. Phytochemicals with similar chemical structures are grouped. Accordingly, there are two main groups of phytochemicals, flavonoid and non-flavonoid. Various in vitro and in vivo studies on phytochemicals have proven neuroprotective effects by increasing cognitive function with their anti-inflammatory and antioxidant mechanisms. The purpose of this review is to summarize the in vitro and in vivo studies on phytochemicals with neuroprotective effects and to provide insight.

Therapeutic Potential of Capsaicin in Various Neurodegenerative Diseases with Special Focus on Nrf2 Signaling

Neurodegenerative disease is mainly characterized by the accumulation of misfolded proteins, contributing to mitochondrial impairments, increased production of proinflammatory cytokines and reactive oxygen species, and neuroinflammation resulting in synaptic loss and neuronal loss. These pathophysiological factors are a serious concern in the treatment of neurodegenerative diseases. Based on the symptoms of various neurodegenerative diseases, different treatments are available, but they have serious side effects and fail in clinical trials, too. Therefore, treatments for neurodegenerative diseases are still a challenge at present. Thus, it is important to study an alternative option. Capsaicin is a naturally occurring alkaloid found in capsicum. Besides the TRPV1 receptor activator in nociception, capsaicin showed a protective effect in brain-related disorders. Capsaicin also reduces the aggregation of misfolded proteins, improves mitochondrial function, and decreases ROS generation. Its antioxidant role is due to increased expression of an nrf2-mediated signaling pathway. Nrf2 is a nuclear erythroid 2-related factor, a transcription factor, which has a crucial role in maintaining the normal function of mitochondria and the cellular defense system against oxidative stress. Intriguingly, Nrf2 mediated pathway improved the upregulation of antioxidant genes and inhibition of microglial-induced inflammation, improved mitochondrial resilience and functions, leading to decreased ROS in neurodegenerative conditions, suggesting that Nrf2 activation could be a better therapeutic approach to target pathophysiology of neurodegenerative disease. Therefore, the present review has evaluated the potential role of capsaicin as a pharmacological agent for the treatment and management of various neurodegenerative diseases via the Nrf2-mediated signaling pathway.

Preparation and Evaluation of Curcumin Derivatives Nanoemulsion Based on Turmeric Extract and Its Antidepressant Effect

Purpose

The early stage of this study verified that a turmeric extract (TUR) including 59% curcumin (CU), 22% demethoxycurcumin (DMC), and 18% bisdemethoxycurcumin (BDMC), could enhance the stability of CU and had greater antidepressant potential in vitro. The objective of the study was to develop a nano-delivery system containing TUR (TUR-NE) to improve the pharmacokinetic behavior of TUR and enhance its antidepressant effect.

Methods

The antidepressant potential of TUR was explored using ABTS, oxidative stress-induced cell injury, and a high-throughput screening model. TUR-NE was fabricated, optimized and characterized. The pharmacokinetic behaviors of TUR-NE were evaluated following oral administration to normal rats. The antidepressant effect of TUR-NE was assessed within chronic unpredictable mild stress model (CUMS) mice. The behavioral and biochemical indexes of mice were conducted.

Results

The results depicted that TUR had 3.18 and 1.62 times higher antioxidant capacity than ascorbic acid and CU, respectively. The inhibition effect of TUR on ASP+ transport was significantly enhanced compared with fluoxetine and CU. TUR-NE displayed a particle size of 116.0 ± 0.31 nm, polydispersity index value of 0.121 ± 0.007, an encapsulation rate of 98.45%, and good release and stability in cold storage. The results of pharmacokinetics indicated the AUC(0-t) of TUR-NE was 8.436 and 4.495 times higher than that of CU and TUR, while the Cmax was 9.012 and 5.452 times higher than that of CU and TUR, respectively. The pharmacodynamic study confirmed that the superior antidepressant effect of TUR-NE by significantly improving the depressant-like behaviors and elevating the content of 5-hydroxytryptamine in plasma and brain in CUMS mice. TUR-NE showed good safety with repeated administration.

Conclusion

TUR-NE, which had small and uniform particle size, enhanced the bioavailability and antidepressant effect of TUR. It could be a promising novel oral preparation against depression.

Are We Ready to Recommend Capsaicin for Disorders Other Than Neuropathic Pain?

Capsaicin, a lipophilic, volatile compound, is responsible for the pungent properties of chili peppers. In recent years, a significant increase in investigations into its properties has allowed the production of new formulations and the development of tools with biotechnological, diagnostic, and potential therapeutic applications. Most of these studies show beneficial effects, improving antioxidant and anti-inflammatory status, inducing thermogenesis, and reducing white adipose tissue. Other mechanisms, including reducing food intake and improving intestinal dysbiosis, are also described. In this way, the possible clinical application of such compound is expanding every year. This opinion article aims to provide a synthesis of recent findings regarding the mechanisms by which capsaicin participates in the control of non-communicable diseases such as obesity, diabetes, and dyslipidemia.

Cerebral endothelial cell-derived extracellular vesicles regulate microglial polarization and promote autophagy via delivery of miR-672-5p

The interaction between cerebral endothelial cells (CEC) and brain parenchymal cells is critical to maintain neurovascular homeostasis, whereas extracellular vesicles (EVs) are essential to mediate the cell-cell communication. Previous researches demonstrated that CEC-derived EVs (CEC-EVs) confer neuroprotective actions. However, the molecular mechanisms remain unknown. In this study, we isolated EVs from CEC and assessed their immune-regulatory actions in microglial cells and mice following lipopolysaccharide (LPS) exposure. We found that CEC-EVs treatment significantly ameliorated LPS-induced inflammatory activation, shifting microglial polarization from pro-inflammatory phenotype to anti-inflammatory phenotype. Meanwhile, microglial cells can effectively internalize CEC-EVs and this process was further enhanced by immune activation. Next, the miRNA microarray analysis revealed that CEC-EVs increased expression of miR-672-5p, which was demonstrated to be the cargo of CEC-EVs. TGFβ-activated kinase 1 (TAK1)-binding proteins 2 (TAB2) was identified to be the target of miR-672-5p. Through inhibiting TAB2, miR-672-5p derived from CEC-EVs suppressed TAK1-TAB signaling and thereby mitigating the downstream NF-κB activation. Furthermore, we found that by delivering miR-672-5p, CEC-EVs promoted autophagy and hence stimulating autophagic degradation of NLRP3 inflammasome. Our work firstly revealed the neuroimmune-modulating actions of CEC-EVs and further demonstrated that miR-672-5p secreted from CEC-EVs inhibits microglial pro-inflammatory polarization and facilitates autophagic process via targeting TAB2.

The Role of Gut Microbiota in Anxiety, Depression, and Other Mental Disorders as Well as the Protective Effects of Dietary Components

The number of individuals experiencing mental disorders (e.g., anxiety and depression) has significantly risen in recent years. Therefore, it is essential to seek prevention and treatment strategies for mental disorders. Several gut microbiota, especially Firmicutes and Bacteroidetes, are demonstrated to affect mental health through microbiota-gut-brain axis, and the gut microbiota dysbiosis can be related to mental disorders, such as anxiety, depression, and other mental disorders. On the other hand, dietary components, including probiotics (e.g., Lactobacillus and Bifidobacterium), prebiotics (e.g., dietary fiber and alpha-lactalbumin), synbiotics, postbiotics (e.g., short-chain fatty acids), dairy products, spices (e.g., Zanthoxylum bungeanum, curcumin, and capsaicin), fruits, vegetables, medicinal herbs, and so on, could exert protective effects against mental disorders by enhancing beneficial gut microbiota while suppressing harmful ones. In this paper, the mental disorder-associated gut microbiota are summarized. In addition, the protective effects of dietary components on mental health through targeting the gut microbiota are discussed. This paper can be helpful to develop some dietary natural products into pharmaceuticals and functional foods to prevent and treat mental disorders.

The influence of antibiotic treatment on the behavior and gut microbiome of adult rats neonatally insulted with lipopolysaccharide

The present study investigated whether neonatal exposure to the proinflammatory endotoxin lipopolysaccharide (LPS) followed by an antibiotic (ATB)-induced dysbiosis in early adulthood could induce neurodevelopmental disorders-like behavioral changes in adult male rats. Combining these two stressors resulted in decreased weight gain, but no significant behavioral abnormalities were observed. LPS treatment resulted in adult rats' hypoactivity and induced anxiety-like behavior in the social recognition paradigm, but these behavioral changes were not exacerbated by ATB-induced gut dysbiosis. ATB treatment seriously disrupted the gut bacterial community, but dysbiosis did not affect locomotor activity, social recognition, and acoustic reactivity in adult rats. Fecal bacterial community analyses showed no differences between the LPS challenge exposed/unexposed rats, while the effect of ATB administration was decisive regardless of prior LPS exposure. ATB treatment resulted in significantly decreased bacterial diversity, suppression of Clostridiales and Bacteroidales, and increases in Lactobacillales, Enterobacteriales, and Burkholderiales. The persistent effect of LPS on some aspects of behavior suggests a long-term effect of early toxin exposure that was not observed in ATB-treated animals. However, an anti-inflammatory protective effect of ATB cannot be assumed because of the increased abundance of pro-inflammatory, potentially pathogenic bacteria (Proteus, Suttrella) and the elimination of the bacterial families Ruminococcaceae and Lachnospiraceae, which are generally considered beneficial for gut health.

The synergic effects and mechanism of KGM-DMY complex in the prevention of obesity and enhancement of fatigue resistance in mice

Dietary fibers (DFs) are normally consumed together with polyphenols. Further, both of them are two kinds of popular functional ingredients. However, studies have shown that the soluble DFs and polyphenols are antagonistic to their bioactivity due to the potential loss of the physical properties that drive their benefits. In this study, konjac glucomannan (KGM), dihydromyricetin (DMY), and KGM-DMY complex were fed to mice on normal chow diet (NCD) and high fat diet (HFD). The body fat content, serum lipid metabolites and time to exhaustion in swimming were compared. It was found that KGM-DMY had synergistic effects on the reduction of serum triglyceride, total glycerol content in HFD-fed mice, and extension of time to exhaustion in swimming in NCD-fed mice. The underlying mechanism was explored by antioxidant enzyme activity measurement, energy production quantification, and gut microbiota 16S rDNA profiling. KGM-DMY synergistically reduced the lactate dehydrogenase activity, malondialdehyde production, and alanine aminotransferase activities after swimming. Moreover, superoxide dismutase activities, glutathione peroxidase activities, glycogen and adenosine triphosphate contents were synergistically enhanced by KGM-DMY complex. In addition, according to gut microbiota gene expression analyses, KGM-DMY enhanced the ratio of Bacteroidota/Firmicutes and the abundance of Oscillospiraceae and Romboutsia. The abundance of Desulfobacterota was also reduced. To our knowledge, this was the first experiment that indicated that the complex of polyphenols and DF have synergistic effects in obesity prevention and fatigue resistance. The study provided a perspective for the formulation of obese preventive nutritional supplement in the food industry.

Lactiplantibacillus plantarum N-1 improves autism-like behavior and gut microbiota in mouse

Introduction

The gut-brain axis has been widely recognized in autism spectrum disorder (ASD), and probiotics are considered to potentially benefit the rescuing of autism-like behaviors. As a probiotic strain, Lactiplantibacillus plantarumN-1(LPN-1) was utilized to investigate its effects on gut microbiota and autism-like behaviors in ASD mice constructed by maternal immune activation (MIA).

Methods

Adult offspring of MIA mice were given LPN-1 at the dosage of 2  ×  109  CFU/g for 4  weeks before subject to the behavior and gut microbiota evaluation.

Results

The behavioral tests showed that LPN-1 intervention was able to rescue autism-like behaviors in mice, including anxiety and depression. In which the LPN-1 treatment group increased the time spent interacting with strangers in the three-chamber test, their activity time and distance in the central area increased in the open field test, and their immobility time decreased when hanging their tails. Moreover, the supplementation of LPN-1 reversed the intestinal flora structure of ASD mice by enhancing the relative abundance of the pivotal microorganisms of Allobaculum and Oscillospira, while reducing those harmful ones like Sutterella at the genus level.

Discussion

These results suggested that LPN-1 supplementation may improve autism-like behaviors, possibly via regulating the gut microbiota.

Dissecting the molecular mechanisms underlying the antidepressant activities of herbal medicines through the comprehensive review of the recent literatures

Depression is clinically defined as a mood disorder with persistent feeling of sadness, despair, fatigue, and loss of interest. The pathophysiology of depression is tightly regulated by the biosynthesis, transport and signaling of neurotransmitters [e.g., serotonin, norepinephrine, dopamine, or γ-aminobutyric acid (GABA)] in the central nervous system. The existing antidepressant drugs mainly target the dysfunctions of various neurotransmitters, while the efficacy of antidepressant therapeutics is undermined by different adverse side-effects. The present review aimed to dissect the molecular mechanisms underlying the antidepressant activities of herbal medicines toward the development of effective and safe antidepressant drugs. Our strategy involved comprehensive review and network pharmacology analysis for the active compounds and associated target proteins. As results, 45 different antidepressant herbal medicines were identified from various in vivo and in vitro studies. The antidepressant mechanisms might involve multiple signaling pathways that regulate neurotransmitters, neurogenesis, anti-inflammation, antioxidation, endocrine, and microbiota. Importantly, herbal medicines could modulate broader spectrum of the cellular pathways and processes to attenuate depression and avoid the side-effects of synthetic antidepressant drugs. The present review not only recognized the antidepressant potential of herbal medicines but also provided molecular insights for the development of novel antidepressant drugs.

Qiliqiangxin Modulates the Gut Microbiota and NLRP3 Inflammasome to Protect Against Ventricular Remodeling in Heart Failure

Aims: Pathological left ventricular (LV) remodeling induced by multiple causes often triggers fatal cardiac dysfunction, heart failure (HF), and even cardiac death. This study is aimed to investigate whether qiliqiangxin (QL) could improve LV remodeling and protect against HF via modulating gut microbiota and inhibiting nod-like receptor pyrin domain 3 (NLRP3) inflammasome activation.

Methods: Rats were respectively treated with QL (100 mg/kg/day) or valsartan (1.6 mg/kg/day) by oral gavage after transverse aortic constriction or sham surgery for 13 weeks. Cardiac functions and myocardial fibrosis were assessed. In addition, gut microbial composition was assessed by 16S rDNA sequencing. Furthermore, rats’ hearts were harvested for histopathological and molecular analyses including immunohistochemistry, immunofluorescence, terminal-deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphated nick end labeling, and Western blot.

Key findings: QL treatment preserved cardiac functions including LV ejection fractions and fractional shortening and markedly improved the LV remodeling. Moreover, HF was related to the gut microbial community reorganization like a reduction in Lactobacillus, while QL reversed it. Additionally, the protein expression levels like IL-1β, TNF-α, NF-κB, and NLRP3 were decreased in the QL treatment group compared to the model one.

Conclusion: QL ameliorates ventricular remodeling to some extent in rats with HF by modulating the gut microbiota and NLRP3 inflammasome, which indicates the potential therapeutic effects of QL on those who suffer from HF.

Effect of dendrobium mixture in alleviating diabetic cognitive impairment associated with regulating gut microbiota

Dendrobium mixture (DM) is a patent Chinese herbal formulation consisting of Dendrobii Caulis, Astragali Radix, Rehmanniae Radix as the main ingredients. DM has been shown to alleviate diabetic related symptoms attributed to its anti-hyperglycaemic and anti-inflammatory activities. However, the effect on diabetic induced cognitive dysfunction has not been investigated. This study aims to investigate the effect of DM in improving diabetic cognitive impairment and associated mechanisms. Our study confirmed the anti-hyperglycaemic effect of DM and showed its capacity to restore the cognitive and memory function in high fat/high glucose and streptozotocin-induced diabetic rats. The neuroprotective effect was manifested as improved learning and memory behaviours, restored blood-brain barrier tight junction, and enhanced expressions of neuronal survival related biomarkers. DM protected the colon tight junction, and effectively lowered the circulated proinflammatory mediators including tumour necrosis factor-α, interleukin-6 and lipopolysaccharides. In the gut microbiota, DM corrected the increase in the abundance of Firmicutes, the increase in the ratio of Firmicutes/Bacteroidetes, and the decrease in the abundance of Bacteroidetes in diabetic rats. It also reversed the abundance of Lactobacillus, Ruminococcus and Allobaculum genera. Short chain fatty acids, isobutyric acid and ethylmethylacetic acid, were negatively and significantly correlated to Ruminococcus and Allobaculum. Isovaleric acid was positively and significantly correlated with Lactobacillus, which all contributing to the improvement in glucose level, systemic inflammation and cognitive function in diabetic rats. Our results demonstrated the potential of DM as a promising therapeutic agent in treating diabetic cognitive impairment and the underlying mechanism may be associated with regulating gut microbiota.

Beneficial Effects of Capsaicin in Disorders of the Central Nervous System

Capsaicin is a natural compound found in chili peppers and is used in the diet of many countries. The important mechanism of action of capsaicin is its influence on TRPV1 channels in nociceptive sensory neurons. Furthermore, the beneficial effects of capsaicin in cardiovascular and oncological disorders have been described. Many recent publications show the positive effects of capsaicin in animal models of brain disorders. In Alzheimer’s disease, capsaicin reduces neurodegeneration and memory impairment. The beneficial effects of capsaicin in Parkinson’s disease and depression have also been described. It has been found that capsaicin reduces the area of infarction and improves neurological outcomes in animal models of stroke. However, both proepileptic and antiepileptic effects of capsaicin in animal models of epilepsy have been proposed. These contradictory results may be caused by the fact that capsaicin influences not only TRPV1 channels but also different molecular targets such as voltage-gated sodium channels. Human studies show that capsaicin may be helpful in treating stroke complications such as dysphagia. Additionally, this compound exerts pain-relieving effects in migraine and cluster headaches. The purpose of this review is to discuss the mechanisms of the beneficial effects of capsaicin in disorders of the central nervous system.

Chronic lead exposure induces fatty liver disease associated with the variations of gut microbiota

BACKGROUND

Lead (Pb) has been suggested as an endocrine-disrupting chemical. However, few studies have investigated the association between chronic Pb exposure and fatty liver disease.

OBJECTIVES

We aimed to investigate the association of chronic Pb exposure with fatty liver disease and whether the variations of the gut microbiota involve in the mechanism of the fatty liver disease induced by chronic Pb exposure.

METHODS

We conducted a cross-sectional study of 3066 rural participants in East China. Blood lead level (BLL) was detected, and abdominal ultrasonography was used to diagnose hepatic steatosis. Both the definition of non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) were used. Wistar rats were randomly divided into two groups and each group was exposed to 0 or 0.05% w/v Pb through drinking water for 28 weeks. The relevant parameters of hepatic lipid metabolism and gut microbiota were analyzed.

RESULTS

In humans, after adjusting for potential confounders, the odds of having NAFLD and MAFLD were significantly increased by 54% and 52% in the participants in the fourth BLL quartile (OR 1.54, 95% CI 1.24, 1.91 and OR 1.52, 95% CI 1.22, 1.89). In the rats, chronic Pb exposure induced the increased visceral fat, hepatic steatosis, and dysbiosis of the gut microbiota, including the decrease of richness, diversity, evenness and phylogenetic diversity of the gut microbiota and the significant alternations of the gut microbiota composition, particularly, the decrease of the relative abundance of Coprococcus and Oscillospira at the genus level.

CONCLUSIONS

Chronic Pb exposure could induce fatty liver disease, which may be associated with the variations of the gut microbiota.

Intracerebroventricular injection of sclerostin reduced social hierarchy and impaired neuronal dendritic complexity in mice

An increasing number of studies have demonstrated extensive functional links between bone and the brain. As a novel endocrine organ, bone has received increasing attention for its upregulatory functions in the brain. Sclerostin, a novel bone-derived endocrine molecule, secreted by osteocytes, can inhibit the bone morphogenetic protein (BMP) and wingless/integrated (Wnt) signaling pathways to regulate bone formation, but its effects on the central nervous system and neurosocial behaviors are unknown. This study investigated the effects of intracerebroventricular sclerostin injection on social-emotional behaviors in adult mice. The results showed that acute elevation of sclerostin levels in the brain could induce anxiety-like behaviors and reduce the social hierarchy of mice while reducing the dendritic complexity of pyramidal neurons in the mouse hippocampus. These data suggested that sclerostin may regulate social-emotional behaviors, providing new evidence for the existence of a bone-brain axis, new insights into the regulation of social behaviors by bone-derived endocrine molecules, and a new direction for the study of individual emotional behavior regulation.

Immune Response Is Key to Genetic Mechanisms of SARS-CoV-2 Infection With Psychiatric Disorders Based on Differential Gene Expression Pattern Analysis

Existing evidence demonstrates that coronavirus disease 2019 (COVID-19) leads to psychiatric illness, despite its main clinical manifestations affecting the respiratory system. People with mental disorders are more susceptible to COVID-19 than individuals without coexisting mental health disorders, with significantly higher rates of severe illness and mortality in this population. The incidence of new psychiatric diagnoses after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is also remarkably high. SARS-CoV-2 has been reported to use angiotensin-converting enzyme-2 (ACE2) as a receptor for infecting susceptible cells and is expressed in various tissues, including brain tissue. Thus, there is an urgent need to investigate the mechanism linking psychiatric disorders to COVID-19. Using a data set of peripheral blood cells from patients with COVID-19, we compared this to data sets of whole blood collected from patients with psychiatric disorders and used bioinformatics and systems biology approaches to identify genetic links. We found a large number of overlapping immune-related genes between patients infected with SARS-CoV-2 and differentially expressed genes of bipolar disorder (BD), schizophrenia (SZ), and late-onset major depressive disorder (LOD). Many pathways closely related to inflammatory responses, such as MAPK, PPAR, and TGF-β signaling pathways, were observed by enrichment analysis of common differentially expressed genes (DEGs). We also performed a comprehensive analysis of protein-protein interaction network and gene regulation networks. Chemical-protein interaction networks and drug prediction were used to screen potential pharmacologic therapies. We hope that by elucidating the relationship between the pathogenetic processes and genetic mechanisms of infection with SARS-CoV-2 with psychiatric disorders, it will lead to innovative strategies for future research and treatment of psychiatric disorders linked to COVID-19.

Oscillospira - a candidate for the next-generation probiotics

Oscillospira is a class of organism that often appears in high-throughput sequencing data but has not been purely cultured and is widely present in the animal and human intestines. There is a strong association between variation in Oscillospira abundance and obesity, leanness, and human health. In addition, a growing body of studies has shown that Oscillospira is also implicated in other diseases, such as gallstones and chronic constipation, and has shown some correlation with the positive or negative changes in its course. Sequencing data combined with metabolic profiling indicate that Oscillospira is likely to be a genus capable of producing short-chain fatty acids (SCFAs) such as butyrate, which is an important reference indicator for screening "next-generation probiotics ". Considering the positive effects of Oscillospira in some specific diseases, such as obesity-related metabolic diseases, it has already been characterized as one of the next-generation probiotic candidates and therefore has great potential for development and application in the future food, health care, and biopharmaceutical products.

High-frequency repetitive transcranial magnetic stimulation alleviates the cognitive side effects of electroconvulsive therapy in major depression

OBJECTIVE

The retrospective study aimed to explore the difference in mood outcomes and cognitive function between high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) over dorsolateral prefrontal cortex (DLPFC) and electroconvulsive therapy in major depression disorder (MDD) patients and to examine the improvement of HF-rTMS on cognitive impairment evoked by electroconvulsive therapy (ECT).

MATERIALS AND METHODS

A total of 116 participants with MDD, who completed a 4-week follow-up assessment, were enrolled. The cohort consisted of 26 cases classed as control, 46 participants administrated with HF-rTMS (HF-rTMS group), 22 patients treated with ECT (ECT group), and 23 cases treated with HF-rTMS and ECT at the course of hospitalization (HF-rTMS + ECT group). Medication was kept constant as well in all participants. The 17-item Hamilton Depression Rating Scale for Depression (HAMD-17) and 14-item Hamilton Anxiety Rating Scale (HAMA-14) were used to assess depression and anxiety, respectively. Montreal Cognitive Assessment (MoCA) was to elevate cognitive function.

RESULTS

No statistical significance was found for baseline in sociodemographic, characteristics of depression, anxiety and cognition, and psychopharmaceutic dosages among control, HF-rTMS, ECT, and HF-rTMS + ECT groups (p > 0.05). Compared with baseline level, total scores of HAMD-17 and HAMA-14 significantly decreased at the end of 4 weeks after treatment (p < 0.001). Furthermore, the decline in scores of HAMD-17 and its sleep disorder and retardation factors from baseline to post-treatment was greater in HF-rTMS, ECT, and HF-rTMS + ECT group than in control (p < 0.05), and there was a significant difference between control and HF-rTMS group in the decline of psychological factor of HAMA-14 (p < 0.01). ECT treatment evoked total score of MoCA to decrease significantly at the end of 4-week after intervention (p < 0.001), and the decline in scores of MoCA and its delayed recall and language performances from baseline to post-treatment was greater in ECT than control, HF-rTMS, and HF-rTMS + ECT (p < 0.05).

CONCLUSION

High-frequency repetitive transcranial magnetic stimulation improved psychological anxiety and ameliorated the cognition impairment evoked by ECT though it had the same anti-depressant efficacy as ECT.

Baicalin ameliorates chronic unpredictable mild stress-induced depression through the BDNF/ERK/CREB signaling pathway

Brain-derived neurotrophic factor (BDNF) can activate the extracellular regulated protein kinase (ERK)/cAMP response element binding protein (CREB) cascade revealing an important role in antidepressant effects. Here, we studied the neuroprotective effect of baicalin (BA) in mice with chronic unpredictable mild stress (CUMS)-induced via a BDNF/ERK/CREB signaling pathway. Depression was induced via six weeks of CUMS in male ICR mice, and drug therapy was given simultaneously for the last three weeks. Cognitive dysfunctions were then evaluated via sucrose preference test (SPT), open field test (OFT), Morris water maze test (MWM), tail suspension test (TST), and novelty suppressed feeding test (NSF). Western blot and real-time PCR were then used to detect the relative expression of ERK, CREB, p-ERK, and p-CREB. Integrated optical density (IOD) tests of p-ERK and p-CREB were then evaluated via immunofluorescence. The behavior results showed that the cognitive dysfunctions increased in the CUMS group versus the control (CON) group (p < 0.01). There were decreases in fluoxetine (FLU) and BA groups (p < 0.05, p < 0.01). The protein ratios of p-ERK/ERK, p-CREB/CREB and ERK mRNA, and CREB mRNA expression decreased in the CUMS group (p < 0.01) and markedly increased in the FLU and BA groups (p < 0.05, p < 0.01). The IOD value of the p-ERK and p-CREB in the CUMS group was decreased versus the CON group (p < 0.01), and these changes were improved via BA and FLU treatment (p < 0.05, p < 0.01). This study indicated that BA can improve cognitive functions and has antidepressant effects in mice, which may be associated with activation of the BDNF/ERK/CREB signaling pathway in the hippocampus.