Intestinal Flora and Disease Mutually Shape the Regional Immune System in the Intestinal Tract

Hemocyanin-derived antimicrobial peptide PvL1 defense against AHPND infection by regulating the hepatopancreatic microbiota of Penaeus vannamei

Antimicrobial peptides (AMPs) play a crucial role in maintaining the balance of host microbiota, serving as the first line of defense against pathogenic microorganisms. However, the potential mechanisms by which AMPs modulate microbial homeostasis are not fully understood. In this study, we showed that Vibrio parahaemolyticus (VPAHPND) infection could suppress the expression of hemocyanin and promote its degradation. PvL1, a hemocyanin-derived AMP, exhibited high antibacterial activity against AHPND infection. Then, it was observed that PvL1 could restore the dysbiosis in the hepatopancreas microbiota of AHPND shrimps. In addition, PvL1 could increase the survival of shrimp against VPAHPND infection by modulating the predominance of bacteria in the hepatopancreas microbiota. Taken together, these findings highlight the crucial role of hemocyanin-derived peptides in maintaining homeostasis in the hepatopancreas microbiota in response to AHPND disease.

Association of the gut microbiome with diabetic nephropathy and the mediated effect of metabolites: friend or enemy?

OBJECTIVE

The effects of gut microbiome and its metabolites on diabetic nephropathy (DN) have been inadequately elucidated. The aim of this study is to assess the causal effect of gut microbiome on DN and the mediated effect of metabolites by a two-step Mendelian randomization (MR).

METHODS

Datasets of gut microbiome, metabolites, and DN were acquired in genome-wide association studies and screened for single nucleotide polymorphisms according to the underlying assumptions of MR. Subsequently, inverse variance weighted was used as the primary method for MR analysis to assess the causal effect of gut microbiome on DN and the mediated effect of metabolites. Finally, MR-Egger intercept, Cochran's Q test, and leave-one-out sensitivity analysis were used to assess the horizontal pleiotropy, heterogeneity, and robustness of the results, respectively.

RESULTS

The MR analysis demonstrated that Parabacteroides merdae increased the genetic susceptibility to DN by reducing acetylcarnitine (C2) to propionylcarnitine (C3) ratio (mediated proportion 8.95%, mediated effect 0.024) and alpha-ketobutyrate to 3-methyl-2-oxovalerate ratio (mediated proportion 19.90%, mediated effect 0.053). MR Egger showed that these results lack horizontal pleiotropy (p ≥ 0.05). Cochran's Q and sensitivity analysis suggested these results had no heterogeneity (p ≥ 0.05) and were robust.

CONCLUSION

Our findings revealed the pathway by which Parabacteroides merdae increased the genetic susceptibility to DN by regulating acetylcarnitine (C2) to propionylcarnitine (C3) ratio and alpha-ketobutyrate to 3-methyl-2-oxovalerate ratio. It provides new genetic insights for understanding the pathogenesis of DN and related drug research.

Comparative Analysis of Metabolic Dysfunctions Associated with Pristine and Aged Polyethylene Microplastic Exposure via the Liver-Gut Axis in Mice

The accumulation of plastic waste in the environment has raised widespread concern about the impact of microplastics (MPs) on human and environmental health, particularly regarding aged MPs. This study investigated the effects of subchronic dietary intake on pristine and aged polyethylene microplastics (PE-MPs) in C57BL/6J mice. Results revealed that both pristine and aged PE-MPs, at doses of 0.01 and 1 mg/day, induced plasma metabolic changes primarily associated with lipid metabolism and digestive processes. These alterations were reflected in the expression changes of proteins involved in unsaturated fatty acid pathways in the liver as well as a reduction in beneficial gut microbiota. Key contributors in the toxicity of aged PE-MPs included ATP-binding cassette transporters, gut bacteria alterations (notably Lactobacillus, Akkermansia, Parasutterella, and Turicibacter), and significantly altered proteins related to fatty acid elongation, such as acyl-CoA thioesterase enzyme family and elongation of very long chain fatty acid protein 5. These disruptions exacerbated lipid metabolism disorders, potentially contributing to metabolic diseases. Additionally, decreased levels of glutathione S-transferase A proteins, along with reduced hepatic glutathione and increased reactive oxygen species in both the small intestine and liver, suggested that aged PE-MPs aggravated hepatic and intestinal damage through oxidative stress. These findings indicated that aged PE-MPs caused more severe hepatic dysfunction and gut microbiota disruption. This effect was likely mediated by the transfer of fatty acids and signaling molecules through the gut-liver axis, ultimately leading to hepatic lipid metabolism disorders and oxidative stress.

Buyang Huanwu Decoction stabilizes atherosclerotic vulnerable plaques by regulating intestinal flora, TLR4-NF-κB-NLRP3 inflammatory pathway and mitophagy

OBJECTIVE

This study explores the anti-atherosclerosis (AS) effects of Buyang Huanwu Decoction (BYHWD), focusing on its regulatory effects on the TLR4/NF-κB/NLRP3 inflammatory pathway, gut microbiota metabolites, and mitochondrial autophagy. Through the triple regulatory mechanisms of gut microbiota, the TLR4/NF-κB/NLRP3 inflammatory pathway, and mitochondrial autophagy, this study explores a novel strategy for stabilizing vulnerable AS plaques.

MATERIALS AND METHODS

The active components of Buyang Huanwu Decoction (BYHWD) were detected using LC-MS/MS. By feeding a high-fat diet (HFD) and adding 1.3 % choline chloride to the drinking water to induce ApoE-/- mice gut microbiota dysbiosis, an AS mouse model with vulnerable plaques was established. The treatment groups were administered low, medium, and high doses of BYHWD, as well as broad-spectrum antibiotics. The effects of BYHWD on the vulnerable plaque area in the aorta, collagen content, macrophage and α-SMA protein expression, levels of inflammatory cytokines, reactive oxygen species (ROS), LC3 and NLRP3 expression, gut microbiota composition and abundance, serum trimethylamine-N-oxide (TMAO) levels, and the total bile acid content in the liver, serum, and gallbladder, as well as mitochondrial autophagy, were evaluated applying hematoxylin-eosin (HE) staining, Oil Red O staining, Sirius Red staining, immunohistochemistry, ELISA, immunofluorescence, 16S rRNA sequencing, biochemical analysis, and LC-MS detection. Western blot for TLR4, MyD88, ASC, pro-caspase-1, caspase-1, NLRP3, p-NF-κB/NF-κB, GPR41, GPR43, CYP7A1, CYP27A1, FMO3, FXR, TGR5, NIX, BNIP3, FUNDC1, PINK1, and Parkin proteins expression level.

RESULTS

A total of 31 major active components were identified in Buyang Huanwu Decoction (BYHWD). BYHWD significantly reduced the vulnerable plaque area in the ApoE-/- mouse model of AS, decreased the expression of inflammatory cytokines, inhibited the protein expression of TLR4, MyD88, p-NF-κB/NF-κB, ASC, pro-caspase-1, NLRP3, FMO3, NIX, BNIP3, FUNDC1, and PINK1/Parkin in aortic tissues, downregulated ROS levels and mitochondrial autophagy activity, regulated gut microbiota abundance, reduced serum TMAO levels, and up-regulated the expression of gut microbiota-related proteins, including GPR41, GPR43, CYP7A1, CYP27A1, FXR, and TGR5.

CONCLUSION

BYHWD exerts anti-AS effects through the inhibition of the TLR4/NF-κB/NLRP3 inflammatory pathway, modulating the gut microbiota, and stabilizing mitochondrial autophagy. The in-depth investigation of this mechanism effectively expands the therapeutic potential of BYHWD in the prevention and treatment of cardiovascular diseases and provides new theoretical insights and therapeutic targets for AS-related research.

Lactucin alleviates liver fibrosis by regulating the TLR4-MyD88-MAPK/NF-κB signaling pathway through intestinal flora

ETHNOPHARMACOLOGICAL RELEVANCE

Cichorium glandulosum (CG) is a kind of traditional Chinese medicine, mainly produced in Xinjiang and Inner Mongolia, and its medicinal part is mainly the dried root of CG. CG is a commonly used medicine in Uygur medicine, which has good pharmacological effects. Lactucin (LC) in this study is the main sesquiterpene monomer compound obtained from the ethyl acetate extract of CG. The purity of LC obtained by our research group in the previous stage reached 98.1 %, which met the purity requirements of chemical control of traditional Chinese medicine. At present, the research on the pharmacological action of CG mainly focuses on the extract of CG, and there is little research on the monomer compounds and exact pharmacological action mechanism in CG.

AIM OF THE STUDY

The aim of this study is to investigate the mechanism of lactucin (LC) in alleviating liver fibrosis by regulating TLR4-related inflammatory pathway through intestinal flora-intestine-liver axis.

MATERIALS AND METHODS

Firstly, the content of LC was determined by HPLC. In vitro, hepatic fibrosis cell model was induced and cytotoxicity was detected by MTT assay. QRT-PCR and Western Blot were used to detect the effect of LC on the expression of proteins related to TLR4-MyD88-MAPK/NF-κB signaling pathway. In vivo, carbon tetrachloride and dextran sodium sulfate were used to induce liver fibrosis and enteritis in rats. Detection of liver fibrosis index, H&E staining, Sirius red staining, immunofluorescence and Western Blot were used to detect the degree and action pathway of liver fibrosis. 16S rRNA analysis and bile acid targeted metabolism were used to explore the role of intestinal flora in liver fibrosis.

RESULTS

In vitro, LC can significantly inhibit the mRNA levels of TLR4 and related inflammatory factors, inhibit the expression of TLR4-MyD88-MAPK/NF-κB pathway protein, and reduce the level of intracellular reactive oxygen species, with the same effect as TLR4 inhibitors. In vivo, experimental results show that LC can reduce the degree of liver fibrosis and colitis, significantly reduce the levels of MDA and MPO in colon tissue, increase the level of SOD, reduce the activities of HYP, AKP, AST, ALT, TBA and γ-GT in serum, and increase the level of Alb. LC can also inhibit the expression of TLR4-MyD88-MAPK/NF-κB pathway, and inhibit the expression of TLR4 protein in liver and increase the expression of ZO-1 protein in colon. In addition, LC can regulate the flora composition of liver fibrosis and improve bile acid metabolism.

CONCLUSION

This study found that LC can alleviate liver fibrosis, and suggested that the beneficial effect of LC on liver fibrosis may be achieved by regulating TLR4-MyD88-MAPK pathway and improving intestinal flora through intestinal liver axis. At the same time, it is revealed that LC is the main component of CG for treating liver fibrosis, which lays a theoretical foundation for the research and development of new drugs and clinical research of CG in the later period.

Link between gut damage and neurotoxicity with gender differences in zebrafish: Dibutyl phthalate-driven microbiota dysbiosis as a possible major cause

Among plasticizers, dibutyl phthalate (DBP) is widely used in in industry, posing significant health risks to aquatic organisms. In this study, adult male and female zebrafish were exposed to 0 and 30 μg/L DBP for 15 days. Behavioral monitoring, immunofluorescence, protein immunoblotting, and high-throughput sequencing were used to investigate the critical role of the gut microbiome in DBP-induced dysfunction of the zebrafish gut-brain axis. The results showed pronounced, sex-specific toxic effects of acute DBP exposure in adult zebrafish, with males experiencing more severe neurological damage, while females exhibited greater intestinal damage. DBP exposure caused marked anxiety behaviors in males and significant weight loss in females. Males showed reduced neuronal expression, while females exhibited increased intestinal permeability and lower levels of the tight junction protein (ZO-1). The Firmicutes/Bacteroidota (F/B) ratio decreased, indicating severe gut microbiota dysbiosis. Changes in the gut and fecal microbiota composition, along with PICRUSt2 functional predictions, suggest that female zebrafish experienced more severe metabolic disturbances than males. Analysis of key gene expression in the brain-derived neurotrophic factor (bdnf) pathway revealed that changes in the abundance of tryptophan-metabolizing bacteria in the gut may explain the sex-specific effects of DBP on neurotransmitter serotonin levels in the brain, which influence the gut-brain axis in zebrafish. This study contributes to the understanding of toxic effects of DBP on aquatic organisms and provides strong evidence for assessing its environmental risks.

T helper cell 17/regulatory T cell balance regulates ulcerative colitis and the therapeutic role of natural plant components: a review

Ulcerative colitis (UC) is a chronic relapsing inflammatory disease characterized by progressive mucosal damage. The incidence rate of UC is rising rapidly, which makes the burden of medical resources aggravated. In UC, due to various pathogenic factors such as mucosal immune system disorders, gene mutations and environmental factors disrupting the mucosal barrier function, the midgut pathogenic bacteria and exogenous antigens translocate into the lamina propria, thereby aggravating the inflammatory response and further damages the mucosal barrier. During the progression of UC, Th17 populations that cause inflammation generally increase, while Tregs that suppress Th17 activity decrease. Among them, Th17 mediates immune response, Treg mediates immunosuppression, and the coordinated balance of the two plays a key role in the inflammation and immune process of UC. Natural plant components can regulate biological processes such as immune inflammation from multiple levels of proinflammatory cytokines and signaling pathways. These characteristics have unique advantages and broad prospects in the treatment of UC. In immunomodulation, there is substantial clinical and experimental evidence for the modulatory role of natural plant products in restoring balance between Th17/Treg disturbances in UC. This review summarizes the previous studies on the regulation of Th17/Treg balance in UC by natural plant active ingredients, extracts, and traditional Chinese medicine prescriptions, and provides new evidence for the development and design of lead compounds and natural new drugs for the regulation of Th17/Treg balance in the future, and then provides ideas and evidence for future clinical intervention in the treatment of UC immune disorders and clinical trials.

Changes in Intestinal flora is associated with chronic diseases

BACKGROUND

The intestinal flora (IF) has been linked to risks of non-communicable diseases, especially various cancers, stroke, and Alzheimer’s disease. However, many uncertainties of these associations during different stages of growth, development, and aging still exist. Therefore, further in-depth explorations are warranted.

AIM

To explore the associations of the human IF with disease risks during different stages of growth, development, and aging to achieve more accurate and convincing conclusions.

METHODS

Cohort, cross-sectional, case-control, and Mendelian randomization studies published in the PubMed and Web of Science databases until December 31, 2023 were systematically reviewed to clarify the associations of the IF at the genus level with the risks of various non-communicable diseases, which were grouped in accordance with the 10^th revision of the International Classification of Diseases.

RESULTS

In total, 57 studies were included to quantitatively examine the influence of the IF on the risks of 30 non-communicable diseases during different stages of growth, development, and aging. Population studies and Mendelian randomization studies confirmed positive associations of the abundances of Bifidobacterium and Ruminococcus with multiple sclerosis.

CONCLUSION

These findings contribute to a deeper understanding of the roles of the IF and provide novel evidence for effective strategies for the prevention and treatment of non-communicable diseases. In the future, it will be necessary to explore a greater variety of research techniques to uncover the specific mechanisms by which gut microbiota trigger diseases and conduct in-depth studies on the temporal relationship between microbiota alterations and diseases, so as to clarify the causal relationship more accurately.

The association between the gut microbiome and antituberculosis drug-induced liver injury

Background

This study aimed to explore the distinct characteristics of the gut microbiota in tuberculosis (TB) patients who experienced liver injury following anti-TB treatment compared with those who did not.

Method

We employed a nested case-control study design, recruiting newly diagnosed pulmonary TB patients at Tangshan Infectious Disease Hospital. Participants were categorized into the Antituberculosis Drug-Induced Liver Injury (ADLI) group and the Non-ADLI group based on the occurrence of liver injury after treatment. Both groups received identical anti-TB regimens. Stool samples were collected from patients who developed liver injury within 2-3 weeks of starting treatment, alongside matched controls during the same timeframe. The samples underwent 16S rDNA sequencing, and clinical data and blood samples were also collected for further analysis. At the same time, we constructed mouse models to explore the effects of different anti-tuberculosis drugs on gut microbiota.

Results

Following anti-TB treatment, we observed a decrease in microbial diversity and significant structural changes in the gut microbiota of TB patients (P < 0.05). At T1, the Non_ADLI_T1 group presented relatively high levels of Phascolarctobacterium, Anaerofustis and Mailhella. In contrast, the ADLI_ T1 group presented elevated levels of Bacteroides, Veillonella, Clavibacter, Corynebacterium, Anaerococcus, Gardnerella, Peptostreptococcus and Lautropia. At T2, the ADLI_T2 group presented increased levels of Enterococcus, Faecalibacterium, unclassified_f__Burkholderiaceae, Cardiobacterium, Ruminococcus_gnavus_group and Tyzzerella_4 than did the Non_ADLI_T2 group. Additionally, the ADLI_T2 group presented decreased levels of Prevotella_9, Akkermansia, Erysipelotrichaceae_UCG-003, Rubrobacter and norank_f__Desulfovibrionaceae than did the Non_ADLI_T2 group. In animal experiments, similar changes to those in the human population were observed in the mouse model compared to the control group. Any single anti-tuberculosis drug or two-drug combination or three-drug combination can cause dysbiosis of the mouse gut microbiota. The signature genera between groups are different and related to the type of anti-tuberculosis drug.

Conclusion

Anti-tuberculosis treatment induces dysbiosis in the gut microbiota of TB patients. Notably, there are significant differences in microbiota characteristics between TB patients with and without liver injury at both onset and during treatment. There are some differences in the characteristics of bacterial flora in liver injury caused by different drugs.

Advancements in the investigation of gut microbiota-based strategies for stroke prevention and treatment

Stroke represents a predominant cause of mortality and disability on a global scale, impacting millions annually and exerting a considerable strain on healthcare systems. The incidence of stroke exhibits regional variability, with ischemic stroke accounting for the majority of occurrences. Post-stroke complications, such as cognitive impairment, motor dysfunction, and recurrent stroke, profoundly affect patients' quality of life. Recent advancements have elucidated the microbiota-gut-brain axis (MGBA), underscoring the complex interplay between gut health and brain function. Dysbiosis, characterized by an imbalance in gut microbiota, is significantly linked to an elevated risk of stroke and unfavorable outcomes. The MGBA plays a crucial role in modulating immune function, neurotransmitter levels, and metabolic byproducts, which may intensify neuroinflammation and impair cerebral health. This review elucidates the role of MGBA in stroke pathophysiology and explores potential gut-targeted therapeutic strategies to reduce stroke risk and promote recovery, including probiotics, prebiotics, pharmacological interventions, and dietary modifications. However, the current prevention and treatment strategies based on intestinal flora still face many problems, such as the large difference of individual intestinal flora, the stability of efficacy, and the long-term safety need to be considered. Further research needs to be strengthened to promote its better application in clinical practice.

Modulating effects of mycotoxin and oxidized oil on intestinal microbiota in broiler chickens

Climatic change and increased use of alternative sources of feed ingredients could influence poultry production. Mycotoxin and oxidized oil are two contaminations that may occur in chicken feed as a result of climate change and use of alternative feed ingredients, and these factors may have differential and potentially additive effects on birds' intestinal microbiota. The study objective was to determine the main effects of corn, oil quality, and their interaction on ileal content, ileal scrapings, cecal content, and whole cecum (content and tissue) microbiota in broiler chickens. Broiler chickens were raised for 21 days post-hatch and fed diet made with regular or mycotoxin-contaminated corn (7,959 ppb of deoxynivalenol, 2.1 ppm of aflatoxin, 23,200 ppb of fumonisin, and 1,403 ppb of zearalenone), and regular or oxidized (148 meq/kg) oil. Bacterial genomic DNA was extracted and sequenced targeting the variable (V3-V4) region of the 16S gene. The bioinformatic and statistical analysis of the microbiota data showed mycotoxin and mycotoxin by oxidized oil interaction increased the richness and evenness in the ileal content and only evenness in the cecal content. Mycotoxin and mycotoxin by oxidized oil interaction also increased beta diversity based on the variability in microbial community in the ileal content while increasing the abundance of bacterial taxa, including Streptomyces and Escherichia-Shigella, and predicted pathways related to RNA and DNA synthesis (Mycothiol and pyrimidine deoxyribonucleotides synthesis) and redox regulation (ergothioneine biosynthesis) in ileal content and pathways related to glycol metabolism and degradation and amino acids degradation were increased in the cecal content. Streptomyces has been associated with mycotoxin detoxication, and its increase could reduce the negative effects of mycotoxins contrary to Escherichia-Shigella, which has been negatively correlated with weight gain in chickens. These results show that mycotoxin alone and its combination with oxidized oil affect bacterial diversity and abundance mostly in the ileum content and predicted metabolic pathways across intestinal sections.

Exploring the pathogenesis of RA through the gut-articular axis-dysbiosis a potential factor

Rheumatoid arthritis (RA) is a chronic autoimmune disease with a complex etiology. It has been suggested that the pathogenesis of RA begins in the mucosa and then transitions to the joints when many factors interact, including microbial dysbiosis, inflammatory responses, and immune abnormalities at the mucosal site. Data from RA animals and patients suggest there are changes in the mucosal microflora before the onset of RA, and that dysbiosis of the mucosal ecology continues to play a role in the development of arthritis. Microbial dysbiosis of the mucosa reduces the normal barrier function of the intestinal tract, promotes inflammatory reactions in the mucosal areas of the intestines, and then activates the intestinal immune cells abnormally to produce a large number of auto-reactive antibodies that exacerbate arthritis. Current findings do not clarify whether dysbiosis is only a potential trigger for the development of RA. If it is possible to intervene in such microbial changes before the onset of RA, could the clinical symptoms of arthritis be prevented or reduced? Finding new ways to regulate gut flora composition to maintain gut barrier function is an ongoing challenge for the prevention and treatment of RA.

Short-chain fatty acids mediate gut microbiota-brain communication and protect the blood-brain barrier integrity

The human gut, with a complex community of microbes, is essential for maintaining overall health. This gut microbiota engages in two-way communication with the central nervous system, collectively known as the gut microbiota-brain axis. Alterations in gut microbiota have been associated with various neurological disorders, and disruptions to the blood-brain barrier (BBB) may be crucial, though the exact mechanisms remain unknown. In the current study, we investigated the impacts of short-chain fatty acids (SCFAs) on the integrity of the BBB, which was compromised by orally administered antibiotics in rhesus monkeys and C57BL/6n mice. Our results showed that SCFA supplementation notably enhanced BBB integrity in rhesus monkeys with gut dysbiosis. Similar outcomes were observed in mice with gut dysbiosis, accompanied by decreased cortical claudin-5 mRNA levels. In particular, propionate, but not acetate or butyrate, could reverse the antibiotic-induced BBB permeability increase in mice. Additionally, in vitro studies demonstrated that propionate boosted the expression of tight junction proteins in brain endothelial cells. These results suggest that the propionate can maintain BBB integrity through a free fatty acid receptor 2-dependent mechanism. This study offers new insights into the gut-brain axis and underscores potential therapeutic targets for interventions based on gut microbiota.

The Therapeutic Potential of Gut-Microbiota-Derived Metabolite 4-Phenylbutyric Acid in Escherichia coli-Induced Colitis

Pathogenic Escherichia coli (E. coli) is a widely distributed pathogen that can cause varying degrees of zoonotic diseases, and infected animals often experience intestinal inflammation accompanied by diarrhea and dysbiosis. Previously, for the first time, we isolated Escherichia coli primarily of type B2 from a large-scale dairy farm in Yunnan, China. The 16s rRNA sequencing showed significant differences in the gut microbiota of calves infected with B2 E. coli, with higher abundance of harmful bacteria and lower abundance of beneficial bacteria compared with healthy calves. The metabolomics indicated that the concentrations of oxoadipic acid, 16-oxopalmitate, oerillyl alcohol, palmitoleic acid, and 4-phenylbutyrate (4-PBA) were significantly higher in the healthy group than in the infected group. The mouse model was established to assess the regulatory effect of 4-PBA on E. coli-induced colitis. Both oral administration of 4-PBA and fecal microbiota transplantation (FMT) had strong resistance to E. coli infection, improved survival rate and body weight, reduced intestinal tissue damage, decreased the levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), and restrained TLR4/MyD88/NF-κB pathway. Our study demonstrated that 4-PBA could relieve E. coli-induced colitis by improving gut microbiota structure and inhibiting the expression of pro-inflammatory cytokines through the TLR4/MyD88/NF-κB pathway. The present finding reveals the therapeutic potential of the gut-microbiota-derived metabolite 4-PBA for the treatment of colitis caused by E. coli.

Effects of oral supplementation of probiotics on body weight and visceral fat in obese patients: a meta-analysis and systematic review

Obesity can mediate the occurrence of many cardiovascular metabolic diseases, such as coronary heart disease and diabetes, which will lead to a significant increase in all-cause mortality in obese people. Visceral fat refers to the excessive accumulation of adipose tissue in abdominal organs, which can lead to impaired normal function of organs. In recent years, it has been reported that probiotics can reduce obesity and visceral fat content, and some studies have put forward the opposite conclusion. In order to guide the practice of nutrition, we use Meta-analysis method to analyze these conclusions. The authors searched randomized controlled trials on the effects of oral probiotics on body weight and visceral fat content in obese people published before January 2024 in several public databases, such as PubMed, Web of Science, EMBASE, Cochrane Library and CNKI. The primary outcome was body weight, and the secondary outcomes included BMI, waist circumference, visceral fat content, and low-density lipoprotein levels. This trial has been registered in PROSPERO (CRD42024521353). A total of 8 randomized controlled trials involving 412 patients were included in this meta-analysis. Meta-analysis showed that the weight loss of the experimental group taking probiotics was significantly higher than that of the control group (P < 0.00001). The reduction of waist circumference in the experimental group taking probiotics was significantly different from that in the control group (P = 0.01). The decrease of visceral fat content in the experimental group taking probiotics was significantly different from that in the control group (P < 0.00001). There was no significant difference in BMI and LDL-C levels between the experimental group and the control group. Oral probiotics can reduce weight loss, waist circumference and visceral fat content in obese patients, which may be a potential nutritional treatment for obese patients in the future. However, whether oral probiotics can reduce BMI and LDL-C levels in obese patients needs to be included in more RCTs and further discussed in the future.

Dexmedetomidine Protects the Brain: Exploring the α2AR/FAK Pathway in Post-Stroke Intestinal Barrier Repair

INTRODUCTION

Globally, ischemic stroke is a major cause of mortality and disability, posing a significant challenge in clinical practice and public health. Recent studies have reported that stroke leads to the impairment of the intestinal barrier and the migration of intestinal bacteria to multiple organs. This process exacerbates neurological damage by further impairing intestinal barrier function and leading to bacterial translocation. Dexmedetomidine (Dex), an α2-adrenoceptor (α2AR) agonist, has proven anti-cerebral ischemic effects, yet its effects in post-stroke intestinal dysfunction remain unclear. This study aimed to determine whether Dex mitigates intestinal dysfunction and brain injury following cerebral ischemia-reperfusion.

METHODS

A C57BL/6J mouse model of middle cerebral artery occlusion (MCAO) was used for in vivo experiments, while lipopolysaccharide (LPS)-induced Caco-2 monolayers served as an in vitro model of intestinal barrier dysfunction. Neuronal apoptosis was evaluated using neuronal nuclei (NeuN) and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) double labeling. Reverse transcription-quantitative PCR (RT-qPCR) was performed to measure pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6. Intestinal permeability was assessed using histological score, serum fluorescein isothiocyanate (FITC)-dextran fluorescence, and endotoxin levels. The expression levels of epithelial cadherin (E-cadherin), zonula occludens-1 (ZO-1), and occludin were analyzed by western blot and immunofluorescence. Statistical analyses included analysis of variance with Tukey's post-hoc test.

RESULTS

Dex treatment significantly reduced cerebral infarct volume (p < 0.001) and improved neurological scores compared to MCAO controls. Neuronal apoptosis was significantly inhibited (p < 0.01), as evidenced by reduced TUNEL-positive cells in Dex-treatment MCAO mice. TNF-α, IL-1β and IL-6 were markedly downregulated (p < 0.05). While MCAO increased intestinal permeability (elevated serum FITC-dextran and endotoxin levels, p < 0.01), Dex treatment restored barrier integrity. Dex upregulated E-cadherin expression significantly (p < 0.05) but did not restore the decreased levels of ZO-1 and occludin following MCAO. Dex promoted intestinal permeability repair and alleviated brain injury via the α2AR/focal adhesion kinase (FAK) pathway in MCAO mice. Similarly, Dex mitigated LPS-induced barrier dysfunction in Caco-2 monolayers by restoring FAK expression and improving intestinal barrier integrity.

CONCLUSIONS

Dex alleviates post-stroke intestinal barrier dysfunction and mitigates brain injury, possibly through activating the α2AR/FAK pathway. These findings underscore a potential therapeutic strategy for addressing secondary complications of ischemic stroke and improving patient outcomes.

The Occurrence and Meta-Analysis of Investigations on Intestinal Parasitic Infections Among Captive Wild Mammals in Mainland China

This study investigated the infection rates of intestinal parasites in captive wild animals from 2000 to 2024 and analyzed the associated risk factors using a meta-analysis. We retrieved 29 studies, with a total of 8421 captive wild mammals, published between 2000 and 2024. We used the DerSimonian-Laird model and calculated infection rate estimates with the variance stabilizing double arcsine transformation. The results revealed that the overall prevalence of gastrointestinal parasitic infections in captive wild mammals in mainland China was found to be 53.9%. The highest infection rate was observed for nematodes at 45.1%. Seasonal subgroup analysis revealed the highest incidence in summer at 61.8% and 61.6% in winter. In the class order Mammalia, the highest infection rate was found in the Primates at 66.5% and similarly high values were determined in several other orders like Artiodactyla (59%), Rodentia (57.1%), Carnivora (53.3%) and extremely low in Proboscidea (19.9%). The highest overall infection rate was recorded in summer. The infection rate of gastrointestinal parasites in captive wild mammals in mainland China is notably high. Additionally, parasitic infection rates in captive animals were found to be lower in economically developed regions of mainland China.

Integrative multi-omics analysis of radionuclide-induced intestinal injury reveals the radioprotective role of L-citrulline through histone H3-mediated Cxcl3

BACKGROUND

The widespread application of nuclear technology has markedly heightened the risk of extensive, uncontrolled exposure to radiation. Nevertheless, in contrast to external irradiation, the biological impacts and countermeasures against internal irradiation from radionuclides remain inadequately characterized.

METHODS

Mice were administered yttrium-90 (Y90) carbon microspheres via gavage at different dosages (0-5.0 mCi) to establish a radionuclides exposure model. A multi-omics analysis was employed to access alterations in gut microbiota, fecal and colonic metabolites profiles, and intestinal mRNA expression post-irradiation. The function of significant metabolite was validated at both cellular levels and organismal levels. Additionally, ChIP-Seq and RNA-Seq techniques were utilized to investigate the molecular mechanism underlying the actions of key metabolite.

RESULTS

Exposure to Y90 resulted in intestinal damage and hematological impairment. Multi-omics analysis revealed significant alternations of gut microbiota, fecal metabolites, colonic metabolites, and intestinal mRNA expression following internal radiation exposure. Notably, L-citrulline was identified as a metabolite with changes observed in both fecal and colonic tissues, demonstrating radioprotective properties in vitro and in vivo. Mechanistically, L-citrulline facilitated the citrullination of histone H3 at the 17th site (H3Cit17), and multiple mRNAs including C-X-C motif chemokine ligand 3 (Cxcl3), were transcriptionally regulated by H3Cit17 post L-citrulline treatment. Furthermore, Cxcl3 conferred protective effects for intestinal epithelial cells against ionizing radiation.

CONCLUSIONS

The research offers critical perspectives on the intestinal and gut microbiota's reaction to radionuclides exposure. It underscores the promise of L-citrulline as a radioprotective compound, which may have substantial ramifications for the formulation of strategies to mitigate radiation exposure.

To explore pharmacodynamic substances and mechanism of Xuanfei Baidu Decoction on LPS-induced ALI / ARDS by pharmacochemistry and metabolomics

ETHNOPHARMACOLOGICAL RELEVANCE

Xuanfei Baidu Decoction (XFBD) is made up of five classic prescriptions, which is composed of 13 traditional Chinese medicines, which have the effects of dispersing lung and resolving dampness, clearing heat and evil, purging lung and detoxification. It is used for epidemic diseases caused by damp toxin obstructing lung. In this paper, the endogenous and exogenous metabolites of ALI/ARDS rats after oral administration of XFBD were studied and the material basis and metabolic pathway of XFBD in relieving ALI/ARDS were explained.

MATERIALS AND METHODS

In this study, UPLC-Q-TOF/MS qualitative analysis method was established, and plasma-urine-feces pharmacochemistry was used to identify metabolites in plasma, urine and feces after oral administration of XFBD in rats. RT-PCR and immunohistochemistry were used to study the expression of CYP protein in XFBD and monomeric compounds. In addition, the functional mechanism of XFBD in ALI/ARDS rats was elucidated by non-targeted metabolomics.

RESULTS

A total of 77 prototype components and 389 metabolites in plasma, urine and feces were identified by exogenous components, mainly including oxidation, reduction, hydrolysis, glucuronidation, sulfation and other reactions. The results of RT-PCR and immunohistochemistry showed that the activity of CYP was inhibited under the pathological state of ALI/ARDS. At the same time, XFBD and its monomeric compounds can change the metabolic process of drugs in vivo by inducing or inhibiting the activity of CYPs. The metabolic process of drugs in vivo is the result of the combined action of different CYPs. In addition, a total of 33 differential metabolites were identified in plasma, 45 in urine and 14 in feces, which were mainly related to the synthesis and degradation of ketone bodies, phenylalanine metabolism, tyrosine metabolism, histidine metabolism, butyric acid metabolism and other metabolic pathways.

CONCLUSIONS

This study conducted a relatively scientific and systematic analysis of XFBD. A UPLC-Q-TOF/MS qualitative analysis method was established to identify 77 prototype components and 389 metabolites in plasma, urine and feces of rats after oral administration of XFBD.An ARDS rat model was established to analyze the pharmacokinetic differences of XFBD in normal and ARDS model rats and its regulation effect on CYPs.Non-targeted metabolomics was used to identify the pattern recognition of ARDS pathological model, the diagnosis of disease and the intervention effect of XFBD on ARDS. Preliminary discussion was conducted to provide a theoretical basis for clinical rational drug use.

Gut microbiota and their metabolites in the immune response of rheumatoid arthritis: Therapeutic potential and future directions

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by persistent joint inflammation, damage, and loss of function. In recent years, the role of gut microbiota and its metabolites in immune regulation has attracted increasing attention. The gut microbiota influences the host immune system's homeostasis through various mechanisms, regulating the differentiation, function, and immune tolerance of immune cells. Dysbiosis of the gut microbiota in RA patients is closely associated with abnormal activation of immune cells and excessive secretion of inflammatory cytokines. Metabolites produced by the gut microbiota, such as short-chain fatty acids (SCFAs), tryptophan metabolites, bile acids, and amino acid metabolites, play a critical role in immune responses, regulating the functions of immune cells like T cells, B cells, and macrophages, and inhibiting the release of pro-inflammatory cytokines. Restoring the balance of the gut microbiota and optimizing the production of metabolic products may become a new strategy for RA treatment. This review discusses the role of gut microbiota and its metabolites in the immune response of RA, exploring how they influence the immunopathological process of RA through the regulation of immune cells and key immune factors. It also provides a theoretical basis for future therapeutic strategies based on gut microbiota modulation.

The characteristics of intestinal microflora in infants with rotavirus enteritis, changes in microflora before and after treatment and their clinical values

Rotavirus (RV) is a leading pathogen causing diarrhea in children. In this study, a total of 51 fecal samples from children with RV enteritis, 29 post-treatment fecal samples, and 38 fecal samples from age-matched healthy controls were collected. Microbial DNA was isolated from the samples followed by high throughput Illumina sequencing targeting 16 S rRNA gene. Compared to the healthy group, the RV-infected group exhibited reduced microbial diversity. Both groups shared Firmicutes as the dominant phylum. Additionally, the abundance of Proteobacteria increased significantly in the RV-infected group. At the genus level, among the top 50 most abundant genera, 34 showed significant differences, with these differential genera correlating with certain clinical indicators such as dehydration levels and C-reactive protein (CRP). Notably, there were no significant differences in the microbiota before and after treatment in RV-infected children. Only 8.82% (3/34) of the differential genera in the post-treatment group showed a recovery trend towards the healthy state. This study enhances the understanding of how RV infection alters the gut microbiota structure in children and provides a scientific basis for improving clinical diagnosis and treatment strategies.

How do probiotics alleviate constipation? A narrative review of mechanisms

Constipation is a common gastrointestinal condition, which may occur at any age and affects countless people. The search for new treatments for constipation is ongoing as current drug treatments fail to provide fully satisfactory results. In recent years, probiotics have attracted much attention because of their demonstrated therapeutic efficacy and fewer side effects than pharmaceutical products. Many studies attempted to answer the question of how probiotics can alleviate constipation. It has been shown that different probiotic strains can alleviate constipation by different mechanisms. The mechanisms on probiotics in relieving constipation were associated with various aspects, including regulation of the gut microbiota composition, the level of short-chain fatty acids, aquaporin expression levels, neurotransmitters and hormone levels, inflammation, the intestinal environmental metabolic status, neurotrophic factor levels and the body's antioxidant levels. This paper summarizes the perception of the mechanisms on probiotics in relieving constipation and provides some suggestions on new research directions.

Exploring Mechanism of Electroacupuncture in Modulating Neuroinflammation Based on Intestinal Flora and Its Metabolites

Neuroinflammatory responses play an important role in the pathogenesis of various diseases, particularly those affecting the central nervous system. Inhibition of neuroinflammation is a crucial therapeutic strategy for the management of central nervous system disorders. The intestinal microbial-gut-brain axis serves as a key regulatory pathway that modulates neuroinflammatory processes. Intestinal flora metabolites such as short-chain fatty acids, indoles and their derivatives, lipopolysaccharides, trimethylamine oxide, and secondary bile acids exert direct or indirect effects on neuroinflammation. Studies have shown that electroacupuncture (EA) modulates the composition of the intestinal microbiota and its metabolites, while also suppressing neuroinflammation by targeting the TLR4/NF- κ B, NLRP3/caspase-1, and microglial cell M2-type transformation pathways. This review discusses the mechanisms by which EA regulates neuroinflammation via intestinal microbiota and its metabolites, providing information and a foundation for further investigation of the precise therapeutic mechanisms of EA in neurological disorders.

Gut Microbiota and Metabolite Profiles Associated With Functional Constipation Severity

Functional constipation (FC) is a common digestive disorder that affects patients' quality of life and is closely associated with intestinal tumors. This study used a cross-sectional design to assess the changes of intestinal flora and metabolites in different severities of FC patients through 16S rRNA sequencing and metabolomics analysis. Results showed that patients with severe FC had significantly higher clinical and anxiety scores compared to those in the mild and moderate groups. The species richness of intestinal microorganisms in the severe FC group was also significantly higher, and obvious differences in the flora composition existed. Specifically, the Bacteroidota was more abundant in the severe FC group, which was a characteristic feature distinguishing severe FC. Metabolomic analyses also revealed metabolite differences among patients with mild-to-moderate and severe FC, with the severe FC group showing increased enrichment in L-isoleucine biosynthesis and glycolysis metabolic pathways. The short-chain fatty acid-targeted metabolome suggested that a decrease in butyric acid might be related to worsening constipation. This study suggests that specific flora and metabolic pathways could serve as potential diagnostic and therapeutic targets, thereby contributing to the development of new diagnostic and therapeutic approaches to improve the quality of life and therapeutic outcomes for FC patients.

Mouse gut blueprint: regionality and resilience

Mayassi and colleagues utilized spatial transcriptomics to create a comprehensive blueprint of the mouse gut, exploring its adaptability and resilience under perturbed conditions. Their work highlights the adaptive capabilities of the murine gut's regionalized structure, providing insights into how it functions in a coordinated manner and how it responds to external challenges.

Yanghe decoction inhibits inflammation-induced lung metastasis of colorectal cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Positive deficiency and cancer toxicity are the main pathogenesis of colorectal cancer (CRC) lung metastasis. Yanghe decoction (YHD), a traditional Chinese medicine, has the effects of warming yang, tonifying blood, dispersing cold and clearing stagnation, adopting a treatment method that combines supporting the right and dispelling the wrong, which has remarkable efficacy in anti-tumor.Although, its precise mechanism of inhibiting the metastasis of colorectal cancer to the lung is still poorly understood.

AIM OF THE STUDY

This study aimed to elucidate the antitumor properties of YHD within the context of colorectal cancer lung metastasis.

MATERIALS AND METHODS

Ultrahigh-performance liquid chromatography coupled with mass spectrometry (UHPLC-MS) was utilized to analyze the chemical composition of YHD. The anticancer activity of YHD was evaluated in a CRC lung metastasis mouse model by quantifying pulmonary metastatic nodules. The effects of YHD on CRC cell proliferation, apoptosis, cell cycle progression, and invasion were assessed using CCK-8 assays, flow cytometry, and Transwell assays. YHD-mediated immune modulation in tumor-bearing mice was evaluated by analyzing antitumor immunity, immunosuppressive cells, and cytokines in peripheral blood and tumor tissue. Gut microbiota analysis was conducted to determine the impact of YHD on the gut microbiota in mice.

RESULTS

Our analysis identified 1801 chemical markers in YHD. CFA exacerbated lung metastasis in CRC, whereas oral administration of YHD significantly mitigated this effect, as evidenced by the reduced number of metastatic lung nodules in CRC tumor-bearing mice. In vitro experiments demonstrated that YHD inhibits CRC cell proliferation, induces apoptosis, and suppresses invasion. In the lung tissues of mice with CRC metastasis treated with CFA, there was a significant reduction in NK cells and IL-21, along with an increase in M2 macrophages and IL-6. Following YHD treatment, there was a notable increase in NK cells and IL-21, accompanied by a decrease in M2 macrophages and IL-6 in lung tissues. YHD administration was also associated with an increase in beneficial bacterial species such as Bacillus and a decrease in deleterious bacterial species such as Oscillibacter.

CONCLUSION

Our findings demonstrate that YHD inhibits lung metastasis in CRC by suppressing CRC cell proliferation and invasion, in addition to modulating the tumor microenvironment to favor antitumor immunity. These results provide a scientific basis for the clinical application of YHD in the treatment of CRC patients.

Modulation of Intestinal Flora: a Novel Immunotherapeutic Approach for Enhancing Thyroid Cancer Treatment

Over the past 3 years, there has been a growing interest in clinical research regarding the potential involvement of intestinal flora in thyroid cancer (TC). This review delves into the intricate connection between intestinal flora and TC, focusing on the particular intestinal flora that is directly linked to the disease and identifying which may be able to predict potential microbial markers of TC. In order to shed light on the inflammatory pathways connected to the onset of TC, we investigated the impact of intestinal flora on immune modulation and the connection between chronic inflammation when investigating the role of intestinal flora in the pathogenesis of TC. Furthermore, the potential role of intestinal flora metabolites in the regulation of thyroid function was clarified by exploring the effects of short-chain fatty acids and lipopolysaccharide on thyroid hormone synthesis and metabolism. Based on these findings, we further explore the effects of probiotics, prebiotics, postbiotics, vitamins, and trace elements.

Gene prediction of immune cells association between gut microbiota and colorectal cancer: a Mendelian randomization study

Background

An increasing number of studies have revealed that gut microbiota influences the development and progression of Colorectal cancer (CRC). However, whether a causal relationship exists between the two remains unclear, and the role of immune cells in this context is not well understood.

Objective

To elucidate the causal relationship between gut microbiota and CRC and to explore the potential mediating role of circulating immune cells.

Materials and methods

To analyze the causal relationship between gut microbiota and CRC, we employed a univariable Mendelian randomization (UVMR) approach. Subsequently, a two-step multivariable Mendelian randomization (MVMR) to assess the potential mediating role of circulating immune cells. Primarily, applied the Inverse-Variance Weighted method to evaluate the causal relationship between exposure and outcome. To ensure the robustness of the results linking gut microbiota and CRC, we validated the findings using Robust Inverse-Variance Weighted, Penalized Inverse-Variance Weighted, and Penalized Robust Inverse-Variance Weighted methods. Additionally, we employed MR-Egger Intercept to mitigate the influence of horizontal pleiotropy. MR-PRESSO was used to detect and correct outliers by excluding anomalous instrumental variables. Finally, we supplemented our analysis with methods such as Bayesian Weighted Mendelian Randomization (BWMR), Maximum-Likelihood, Lasso, Debiased Inverse Variance Weighted, and Contamination Mixture to establish a robust and compelling causal relationship.

Results

After accounting for reverse causality, horizontal pleiotropy, and various methodological corrections, Bifidobacterium kashiwanohense, GCA-900066755 sp900066755, Geminocystis, and Saccharofermentanaceae exhibited strong and robust causal effects on CRC. Specifically, CD40 on monocytes (2.82%) and CD45 on CD33+HLA-DR+CD14- cells (12.87%) mediated the causal relationship between Bifidobacterium kashiwanohense and CRC risk. Furthermore, CD45 on CD33-HLA-DR+ (3.94%) mediated the causal relationship between GCA-900066755 sp900066755 and CRC risk. Additionally, terminally differentiated CD4+T cells (11.55%) mediated the causal relationship between Geminocystis and CRC risk. Lastly, CD40 on monocytes (2.35%), central memory CD4+T cells (5.76%), and CD28 on CD28+CD45RA+CD8+T cells (5.00%) mediated the causal relationship between Saccharofermentanaceae and CRC risk.

Conclusion

Our mediation MR analysis provides genetic evidence suggesting that circulating immune cells may mediate the causal relationship between gut microbiota and CRC. The identified associations and mediation effects offer new insights into potential therapeutic avenues for CRC.

Mechanistic study of the effect of a high-salt diet on the intestinal barrier

Despite the established link between chronic high salt diet (HSD) and an increase in gut inflammation, the effect of HSD on the integrity of the intestinal barrier remains understudied. The present study aims to investigate the impact of HSD on the intestinal barrier in rats, encompassing its mechanical, mucous, and immune components. Expression levels of intestinal tight junction proteins and mucin-2 (MUC2) in SD rats were analyzed using immunofluorescence. The expression area of goblet cell mucopolysaccharides was assessed through PAS staining. Additionally, serum D-lactic acid, SIgA, β-defensin, and colonic tissue cytokines were measured using ELISA. Rats fed with HSD exhibited decreased expression of tight junction proteins, particularly Occludin, resulting in impairment of the intestinal epithelial barrier and an elevated serum D-lactic acid level. Furthermore, a notable reduction in the expression of goblet cell mucopolysaccharides, along with lower β-defensin and MUC2 levels, was observed. Notably, the SIgA and immune-related cytokines were significantly reduced in the HSD group. HSD disrupts the intestinal barrier in rats, leading to increased permeability and the entry of inflammatory factors into the bloodstream. This finding suggests that HSD may contribute to the pathogenesis of various diseases.

Impact of microplastics on the human digestive system: From basic to clinical

As a new type of pollutant, the harm caused by microplastics (MPs) to organisms has been the research focus. Recently, the proportion of MPs ingested through the digestive tract has gradually increased with the popularity of fast-food products, such as takeout. The damage to the digestive system has attracted increasing attention. We reviewed the literature regarding toxicity of MPs and observed that they have different effects on multiple organs of the digestive system. The mechanism may be related to the toxic effects of MPs themselves, interactions with various substances in the biological body, and participation in various signaling pathways to induce adverse reactions as a carrier of toxins to increase the time and amount of body absorption. Based on the toxicity mechanism of MPs, we propose specific suggestions to provide a theoretical reference for the government and relevant departments.

Causal Association Between Skin Microbiota and Malignant Melanoma: Genetic Insights From Mendelian Randomization

Background

Malignant melanoma (MM) is an extremely aggressive type of skin cancer that represents a major risk to human health. Earlier observational research has indicated that skin microbiota could play a role in the development and advancement of MM. Nevertheless, the causal link between skin microbiota and MM is still unclear.

Methods

Utilizing data from genome-wide association studies (GWAS) conducted on a European cohort, we applied Mendelian randomization (MR) to evaluate the causal link between skin microbiota and MM. The analysis involved various MR methodologies, including inverse variance weighting (IVW), MR-Egger regression, weighted median, weighted mode and simple mode. Furthermore, we performed sensitivity analysis employing the intercept test of MR-Egger, the Cochran's Q test, the MR-PRESSO approach, and a leave-one-out method.

Results

By conducting MR analysis on the KORA FF4 cohort, we identified several skin microbiotas (ASV003 [Staphylococcus (unc).], ASV016 [Enhydrobacter (unc).], and ASV021 [Micrococcus (unc).]) related with an elevated risk of MM. Conversely, genus: Finegoldia and class: Alphaproteobacteria were shown to inhibit the occurrence of MM. Additionally, MR analysis of the PopGen cohort revealed that ASV021 [Micrococcus (unc).] and family: Moraxellaceae were identified as possible risk factors for MM.

Conclusion

Our research offers new insights into the connection between skin microbiota and MM, indicating that skin microbiota might affect the onset and advancement of MM. Therefore, focusing on skin microbiota could be a valuable strategy for the prevention, identification, and management of MM.

The gut microbiome, immune modulation, and cognitive decline: insights on the gut-brain axis

The gut microbiome has emerged as a pivotal area of research due to its significant influence on the immune system and cognitive functions. Cognitive disorders, including dementia and Parkinson's disease, represent substantial global health challenges. This review explores the relationship between gut microbiota, immune modulation, and cognitive decline, with a particular focus on the gut-brain axis. Research indicates that gut bacteria produce metabolites, including short-chain fatty acids (SCFAs), which affect mucosal immunity, antigen presentation, and immune responses, thereby influencing cognitive functions. A noteworthy correlation has been identified between imbalances in the gut microbiome and cognitive impairments, suggesting novel pathways for the treatment of cognitive disorders. Additionally, factors such as diet, environment, and pharmaceuticals play a role in shaping the composition of the gut microbiome, subsequently impacting both immune and cognitive health. This article aims to clarify the complex interactions among gut microbiota, immune regulation, and cognitive disorders, evaluating their potential as therapeutic targets. The goal is to promote microbiome-based treatments and lay the groundwork for future research in this field.

Updated review of research on the role of the gut microbiota and microbiota-derived metabolites in acute pancreatitis progression and inflammation-targeted therapy

Acute pancreatitis (AP) is characterized by autodigestion of the pancreas, and some patients may rapidly progress to systemic inflammation, pancreatic necrosis, and multi-organ failure. Numerous studies have detailed the bidirectional communication networks between the pancreas and the intestinal microbiota, as well as its metabolites. Such crosstalk affects the progression of AP and recovery through intestinal barrier disruption. Furthermore, advances in experimental research and clinical studies have indicated that gut microorganisms exhibit distinct alterations in response to different levels of severity and etiologies of AP. This information has greatly expanded our knowledge of the role of the gut microflora and microbial metabolites in the pathology of disease and has reinforced the basis of therapeutic approaches that target candidate intestinal microbiota. In this review, we aim to provide an overview of the composition and diversity of the gut microbial community, to highlight the candidate bacteria and microbiota-derived metabolites responsible for AP, and to elucidate their interactions with and regulation of immune-relevant receptors in intestinal epithelial cells (IECs) in the host. Future research should focus on identifying and characterizing AP-associated bacterial strains, elucidating their distinct pathogenic mechanisms across different etiologies and stages of AP, and leveraging these insights to develop preventive and therapeutic strategies.

Human milk oligosaccharides: bridging the gap in intestinal microbiota between mothers and infants

Breast milk is an essential source of infant nutrition. It is also a vital determinant of the structure and function of the infant intestinal microbial community, and it connects the mother and infant intestinal microbiota. Human milk oligosaccharides (HMOs) are a critical component in breast milk. HMOs can reach the baby's colon entirely from milk and become a fermentable substrate for some intestinal microorganisms. HMOs can enhance intestinal mucosal barrier function and affect the intestinal function of the host through immune function, which has a therapeutic effect on specific infant intestinal diseases, such as necrotizing enterocolitis. In addition, changes in infant intestinal microbiota can reflect the maternal intestinal microbiota. HMOs are a link between the maternal intestinal microbiota and infant intestinal microbiota. HMOs affect the intestinal microbiota of infants and are related to the maternal milk microbiota. Through breastfeeding, maternal microbiota and HMOs jointly affect infant intestinal bacteria. Therefore, HMOs positively influence the establishment and balance of the infant microbial community, which is vital to ensure infant intestinal function. Therefore, HMOs can be used as a supplement and alternative therapy for infant intestinal diseases.

Growth Characteristics of Sheep-Derived Bacteroides fragilis and Preliminary Research on Effects in Mice and Lambs

With the growing demand for sheep, the sheep farming industry has developed rapidly. However, lamb diarrhea, a disease with high mortality rates, significantly hampers the industry's growth. Traditional antibiotic treatments often disrupt the Intestinal microbiota, induce antibiotic resistance, and cause adverse side effects, highlighting the urgent need to develop alternative therapies. Bacteroides fragilis, a candidate next-generation probiotic, has been closely associated with intestinal health. This study investigated the growth characteristics and probiotic effects of a sheep-derived Bacteroides fragilis isolate, focusing on its efficacy in alleviating lamb diarrhea and infectious intestinal diseases. The experiments demonstrated that the Bacteroides fragilis isolate grows well under mildly acidic conditions (pH 6-8), exhibits some tolerance to bile salts, and has survival rates of 38.89% and 92.22% in simulated gastric and intestinal fluids, respectively, indicating its potential as a probiotic. In a mouse model, Bacteroides fragilis intervention significantly alleviated colonic inflammation caused by Enterohemorrhagic Escherichia coli infection, enhanced tight junction protein expression, mitigated oxidative stress, and improved intestinal barrier function, with high-dose interventions showing superior effects. In lamb trials, Bacteroides fragilis intervention stopped diarrhea in four out of five lambs, partially restored intestinal microbiota diversity, and reduced the abundance of potential pathogens such as Aerococcus suis and Corynebacterium camporealensis. Therefore, Bacteroides fragilis exhibited remarkable effects in regulating intestinal homeostasis, alleviating inflammation, and promoting recovery from diarrhea.

Role of Akkermansia muciniphila in insulin resistance

Insulin resistance (IR) is a pathogenic factor in numerous metabolic diseases. The gut microbiota plays a crucial role in maintaining the function of the intestinal barrier and overall human health, thereby influencing IR. Dysbiosis of the gut microbiota can contribute to the development of IR. Therefore, it is essential to maintain a balanced and diverse gut microbiota for optimal health. Akkermansia muciniphila, a widely present microorganism in the human intestine, has been shown to regulate gastrointestinal mucosal barrier integrity, reduce endotoxin penetration, decrease systemic inflammation levels, and improve insulin sensitivity. Reduced abundance of A. muciniphila is associated with an increased risk of IR and other metabolic diseases, highlighting its correlation with IR. Understanding the role and regulatory mechanism of A. muciniphila is crucial for comprehending IR pathogenesis and developing novel strategies for preventing and treating related metabolic disorders. Individual variations may exist in both the gut microbiota composition and its impact on IR among different individuals. Further investigation into individual differences between A. muciniphila and IR will facilitate advancements in personalized medicine by promoting tailored interventions based on the gut microbiota composition, which is a potential future direction that would optimize insulin sensitivity while preventing metabolic disease occurrence. In this review, we describe the physiological characteristics of A. muciniphila, emphasize its roles in underlying mechanisms contributing to IR pathology, and summarize how alterations in its abundance affect IR development, thereby providing valuable insights for further research on A. muciniphila, as well as new drug development targeting diabetes.

Oral bacteriophage therapy effectively prevent and control of Clostridium perfringens type c infections in newborn piglets

Clostridium perfringens (C. perfringens) type C exhibits strong pathogenicity, often leading to swine dysentery, severely affecting the economic efficiency of the pig farming industry. Bacteriophages as bacterial viruses have many natural advantages and are potent candidates for controlling bacterial infections. In this study, a lytic C. perfringens phage designed as vB_CpeP_15N3 was isolated with the host C. perfringens type C CVCC1155, and its potential for therapy was determined in vitro and in vivo. Despite the narrow host range, phage vB_CpeP_15N3 exhibited a large burst size of 102 PFU/cell following a short latent period of 10 min. In addition, phage vB_CpeP_15N3 remained stable at temperatures ranging from 4 to 50°C and pH levels from 5 to 9 and had a strong antibacterial effect in vitro. Through whole-genome analysis, phage vB_CpeP_15N3 belongs to the family Guelinviridae, genus Brucesealvirus with no genes related to lysogeny and bacterial virulence or resistance. We further demonstrated that phage vB_CpeP_15N3 by oral administration for preventive purposes could significantly alleviate clinical symptoms and jejunal lesions of newborn piglets through the reduced colonization of C. perfringens type C in the jejunum and the level of CPB toxin in the content of jejunum in the newborn piglet model of CVCC1155 infection. In addition, phage vB_CpeP_15N3 by oral administration for preventive purposes could improve the diversity and abundance of the jejunum microbiota in newborn piglets. Moreover, the prevention by phage vB_CpeP_15N3 obtained more effective therapeutic results than phage and gentamicin treatments. Taken together, these findings suggested that phage vB_CpeP_15N3 is a promising alternative of antibiotics for preventing and controlling C. perfringens type C infection of newborn piglets.

Research Progress in the Relationship between Intestinal Flora and Diabetes Mellitus

Diabetes mellitus is a common chronic metabolic disease characterized by a high incidence and disability rate. Intestinal flora refers to the microbial community that lives in the intestines and plays a crucial role in maintaining intestinal health and the human immune system. In recent years, an increasing body of research has revealed a close relationship between intestinal flora and diabetes. The pathophysiological mechanisms between them have also been constantly uncovered, and the regulation of intestinal flora has shown promising efficacy in the adjuvant treatment of diabetes. This study mainly summarized the characteristics and mechanisms of intestinal flora in patients with diabetes in recent years, as well as the methods of regulating intestinal flora to prevent and treat diabetes, and prospected the future research direction. This will offer a theoretical basis for the clinical adjuvant treatment of diabetes with intestinal flora and the development of new drugs.

The Impact of Mycobacterium avium subsp. paratuberculosis on Intestinal Microbial Community Composition and Diversity in Small-Tail Han Sheep

Paratuberculosis (PTB), primarily caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic infection that affects ruminants and is difficult to prevent, diagnose, and treat. Investigating how MAP infections affect the gut microbiota in sheep can aid in the prevention and treatment of ovine PTB. This study examined fecal samples from eight small-tail Han sheep (STHS) at various stages of infection and from three different field areas. All samples underwent DNA extraction and 16S rRNA sequencing. Among all samples, the phyla p. Firmicutes and p. Bacteroidota exhibited the highest relative abundance. The dominant genera in groups M1-M6 were UCG-005, Christensenellaceae_R-7_group, Rikenellaceae_RC9_gut_group, Akkermansia, UCG-005, and Bacteroides, whereas those in groups A-C were Christensenellaceae_R-7_group, Escherichia-Shigella, and Acinetobacter, respectively. The microbial community structure varied significantly among groups M1-M6. Specifically, 56 microbiota consortia with different taxonomic levels, including the order Clostridiales, were significantly enriched in groups M1-M6, whereas 96 microbiota consortia at different taxonomic levels, including the family Oscillospiraceae, were significantly enriched in groups A-C. To the best of our knowledge, this is the first study to report that MAP infection alters the intestinal microbiota of STHS. Changes in p. Firmicutes abundance can serve as a potential biomarker to distinguish MAP infection and determine the infection stage for its early diagnosis. Our study provides a theoretical basis for the treatment of PTB by regulating the intestinal microbiota, including p. Firmicutes.

Vanillin Has Potent Antibacterial, Antioxidant, and Anti-Inflammatory Activities In Vitro and in Mouse Colitis Induced by Multidrug-Resistant Escherichia coli

A large number of cases of infectious colitis caused by multidrug-resistant (MDR) bacteria, such as Escherichia coli, can result in colon damage and severe inflammation. Vanilla, a widely utilized flavor and fragrance compound, is extensively used in various food. However, the effect of vanilla on MDR E. coli-induced infectious colitis has received less attention. In this study, the antibacterial activity of vanillin against MDR E. coli and other bacteria was determined by the microtiter broth dilution method. The antioxidant and anti-inflammatory capacity of vanillin was assessed in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and MDR E. coli-induced mouse colitis. The results demonstrated that vanillin exhibited potent antibacterial activity against various strains of MDR E. coli, Salmonella, and Staphylococcus aureus, with a minimal inhibitory concentration (MIC) of 1.25-2.5 mg/mL and a minimum bactericidal concentration (MBC) of 5-10 mg/mL; it effectively inhibited cell division in E. coli. Vanillin also displayed remarkable antioxidant activity by suppressing the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and reactive oxygen species (ROS) in LPS-stimulated RAW 264.7 cell; it significantly reduced the production of inflammatory mediators including nitroxide (NO), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and interleukin 1β (IL-1β), while increasing interleukin 10 (IL-10). In an MDR E. coli-induced mouse colitis model, vanillin effectively inhibited inflammation by suppressing inflammatory cytokines, mitogen-activated protein kinase (MAPK), and nuclear factor κ-B (NF-κB) cell signaling pathway activation; it ameliorated changes in intestinal microflora characterized by decreased Firmicutes richness alongside increased Bacteroides richness, rebalancing the dysbiosis caused by E. coli. These findings highlight the potential pharmacological applicability of vanillin as a promising bioactive molecule for treating infectious colitis.

Effects of different milk powders on the growth and intestinal flora in weaned rats: Comparison of special formula milk powder with ordinary milk powder

The objective of this investigation was to examine the effects of distinct dosages of infant formula and diverse formula constituents on the growth and development of weaned rats. Fifty specific pathogen-free (SPF) male Sprague-Dawley (SD) rats aged 3 weeks were divided into the basic diet group, 20% ordinary milk powder group, 20% special formula milk powder group, 30% ordinary milk powder group, and 30% special formula milk powder group randomly. After 28 days of feeding, compared with the basic diet group, the body mass and brain/body weight of rats in the 30% ordinary and special formula milk powder groups were decreased. At the Genus level, Bacteroides in the group supplemented with 20% special formula milk powder was significantly lower than that in the basic diet group, and Parabacteroides was significantly lower than that in the 20% ordinary milk powder group. Lactobacillus was significantly higher than those in the basic diet group and the 20% ordinary milk powder group, and Blautia was significantly higher than those in the basic diet group and the 20% and 30% ordinary milk powder groups, and UBA1819 was significantly higher than those in the other groups. The abundance of Parasutterella in the basic diet group was significantly higher than those in the groups supplemented with 20% ordinary milk powder, 20% special formula milk powder, and 30% ordinary milk powder. This study found that different doses and different formula components of infant milk powder could affect body mass and intestinal flora in Sprague-Dawley (SD) rats, and the addition of low-dose (20%) special formula infant milk powder can increase the beneficial bacteria in the intestinal flora of rats and may reduce the pathogenic bacteria.

Exploring pathogenic mechanism and nutritional treatment strategies for hepatic encephalopathy based on the gut-liver axis theory

Hepatic encephalopathy (HE) is a common and serious complication of chronic liver disease patients with complex pathogenesis and limited treatment methods. At present, the treatment strategy mainly focuses on prevention and nutritional support, but there exists certain contradiction between the metabolic needs of HE patients and nutritional treatment. In particular, the balance of ammonia intake and tissue metabolism needs has become the key to controlling the onset of HE and avoiding the vicious cycle. The gut-liver axis theory reveals the two-way interaction between the intestinal microbiota and the liver, providing a new perspective for the prevention and treatment of HE. This paper comprehensively analyses the signal transduction and related biomarkers of the microbiota in the intestinal-liver circulation, and discusses the regulation of the intestinal microbiota, the enhancement of intestinal barrier function, and the optimisation of the absorption and metabolism of nutrients, in order to reduce the occurrence of HE and provide a new treatment direction for the clinical management of HE.

Seasonal Changes and Age-Related Effects on the Intestinal Microbiota of Captive Chinese Monals (Lophophorus lhuysii)

The Chinese monal (Lophophorus lhuysii) is a large-sized and vulnerable (VU in IUCN) bird from southwestern China. This study applied 16S rRNA high-throughput sequencing to comprehensively examine the gut microbiota of captive Chinese monals (located in Baoxing, Sichuan, China) across varying seasons and life stages. Dominant bacterial phyla identified included Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria. Significant seasonal and age-associated shifts were observed within specific bacterial groups, particularly marked by seasonal fluctuations in beta diversity. Moreover, linear discriminant analysis effect size (LEfSe) and functional predictions highlighted distinct winter signatures, indicating possible functional shifts in energy metabolism and disease resistance. In mid-aged adults, an expansion of Gamma-Proteobacteria suggested an elevated susceptibility of the gut microbiota of Chinese monals to chronic disorders and microbial imbalance. Putative pathogenic bacteria exhibited increased abundance in spring and summer, likely driven by temperature, host physiological cycles, interspecies interactions, and competition. These findings imply that the diversity, and structure of the gut microbiota in captive Chinese monals are strongly influenced by seasonal and age-related factors. The insights provided here are essential for improving breeding strategies and preventing gastrointestinal diseases in captivity.

Mechanism of Insomnia After Stroke Based on Intestinal Flora

Stroke has emerged as the second leading cause of mortality. Insomnia after stroke is a highly prevalent complication of stroke with a complex mechanism, impacting daily activities and hindering neurological function rehabilitation while also increasing the risk of stroke recurrence. With the development of molecular biology, intestinal flora has garnered considerable interest in the past few years because of its significant implications for human physiology and pathology. Numerous studies have emphasized the crucial function of intestinal flora in the pathological changes associated with insomnia after stroke. It can influence sleep patterns following a stroke by modulating various pathways, including the hypothalamic-pituitary-adrenal (HPA) axis, immune responses, and neural mechanisms. Disruption of intestinal flora can adversely affect post-stroke sleep quality, while sleep after stroke can also lead to intestinal flora imbalance. Based on the intestinal flora, this paper explores the involvement of hypothalamic-pituitary-adrenal axis (HPA axis), immune pathway and neural pathway in insomnia after stroke, aiming to offer insights for the prevention, treatment, and research of post-stroke insomnia.

Association between gut microbiota and acute upper respiratory tract infection: a Mendelian randomization study

Targeting specific gut microbiota (GM) species to prevent and treat acute upper respiratory tract infection (AURTI) has attracted researchers' attention, but the relationship between the two is unclear. Based on the summary data from genome-wide association studies (GWAS) on GM and five types of AURTIs (acute nasopharyngitis (common cold), acute pharyngitis, acute sinusitis, acute upper respiratory infections, and acute upper respiratory infections of multiple and unspecified sites), we performed two-sample bidirectional Mendelian randomization (MR) to assess the causal relationship. Through inverse variance weighting (IVW) method, we found that 33 potential microbial taxa can influence the occurrence of AURTI. Sensitivity analysis showed no potential horizontal pleiotropy and heterogeneity bias. We further employed multivariable Mendelian randomization to investigate the impact of potential interference factors on the significant associations previously identified, considering aspects such as comorbidities associated with AURTI, seasonal variations, pathogen specificity, and history of antibiotic allergies. Ultimately, 11 microbial taxa remained significantly associated. This study provides robust evidence for a causal relationship between GM and five types of AURTIs, thereby offering a foundation for the development of microbiota-targeted therapies and related probiotic interventions aimed at AURTI.

The Interaction Between Nutraceuticals and Gut Microbiota: a Novel Therapeutic Approach to Prevent and Treatment Parkinson's Disease

Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by the progressive loss of dopaminergic neurons, leading to motor and non-motor symptoms. Emerging research has shed light on the role of gut microbiota in the pathogenesis and progression of PD. Nutraceuticals such as curcumin, berberine, phytoestrogens, polyphenols (e.g., resveratrol, EGCG, and fisetin), dietary fibers have been shown to influence gut microbiota composition and function, restoring microbial balance and enhancing the gut-brain axis. The mechanisms underlying these benefits involve microbial metabolite production, restoration of gut barrier integrity, and modulation of neuroinflammatory pathways. Additionally, probiotics and prebiotics have shown potential in promoting gut health, influencing the gut microbiome, and alleviating PD symptoms. They can enhance the gut's antioxidant capacity of the gut, reduce inflammation, and maintain immune homeostasis, contributing to a neuroprotective environment. This paper provides an overview of the current state of knowledge regarding the potential of nutraceuticals and gut microbiota modulation in the prevention and management of Parkinson's disease, emphasizing the need for further research and clinical trials to validate their effectiveness and safety. The findings suggest that a multifaceted approach involving nutraceuticals and gut microbiota may open new avenues for addressing the challenges of PD and improving the quality of life for affected individuals.

Gut microbiota, allergic rhinitis, vasomotor rhinitis, Mendelian randomization, causal association

OBJECTIVE

Continuous research on the structure and function of intestinal microecology has confirmed the association between gut microbiota and the occurrence, development, and outcome of allergic diseases. Here, we explored the genetic causality between gut microbiota and rhinitis.

METHODS

We conducted a two-sample Mendelian Randomization (MR) study to investigate the genetic causal relationship between gut microbiota and allergic rhinitis and vasomotor rhinitis. Genetic variations in the human gut microbiota were obtained from the summary statistics of the MiBioGen study. Genome-wide summary statistics of rhinitis were obtained from the FinnGen consortium. The causal effect between gut microbiota and rhinitis was assessed using the inverse variance weighted, MR-Egger regression, and weighted median methods. In addition, sensitivity analyses were conducted using different methods, including maximum likelihood, simple mode, and weighted model methods.

RESULTS

The IVW approach revealed a causal association of the genus Ruminococcus gauvreauii group with an increased risk of allergic rhinitis (IVW Odds Ratio [OR = 1.26] [1.04, 1.53], p-value = 0.01645). In addition, the genus Fusicatenibacter (IVW OR = 1.20 [1.02, 1.41], p-value = 0.02868) was causally associated with an increased risk of vasomotor rhinitis.

CONCLUSION

Gut microbiota belonging to different genera exert different effects on allergic rhinitis and vasomotor rhinitis, including reducing the risk of rhinitis, and increasing the risk of rhinitis. New insights into the mechanisms of underlying gut microbiota-associated rhinitis are provided.

LEVEL OF EVIDENCE

Level 5.

The Role of the Trace Element Selenium in Inflammatory Bowel Disease

One set of chronic gastrointestinal disorders called inflammatory bowel disease (IBD) is defined by persistent, non-specific inflammation. Abdominal pain, hematochezia, diarrhea, and other symptoms are among its clinical signs. Currently, managing and treating IBD remains a significant challenge. Patients with IBD frequently have deficits in trace elements. Selenium (Se) is one of the necessary trace elements for normal organismal function. It has several regulatory effects, including anti-oxidation, anti-inflammatory, and defensive properties, via inducing the synthesis of selenoproteins. Patients with IBD have been shown to have lower Se levels in epidemiologic research studies. Several experimental models of IBD suggest that Se or selenoproteins play a key role in microinflammation. We discuss the relationship between Se and IBD in this review, with an emphasis on a summary of potential mechanisms of action and applications of Se in IBD.

Long-chain polyunsaturated fatty acids influence colorectal cancer progression via the interactions between the intestinal microflora and the macrophages

The metabolism of long-chain polyunsaturated fatty acids (LCPUFAs) is closely associated with the risk and progression of colorectal cancer (CRC). This paper aims to investigate the role of LCPUFA in the crosstalk between intestinal microflora and macrophages, as well as the effects of these three parties on the progression of CRC. The metabolism and function of LCPUFA play important roles in regulating the composition of the human gut microflora and participating in the regulation of inflammation, ultimately affecting macrophage function and polarization, which is crucial in the tumor microenvironment. The effects of LCPUFA on cellular interactions between the two species can ultimately influence the progression of CRC. In this review, we explore the molecular mechanisms and clinical applications of LCPUFA in the interactions between intestinal microflora and intestinal macrophages, as well as its significance for CRC progression. Furthermore, we reveal the role of LCPUFA in the construction of the CRC microenvironment and explore the key nodes of the interactions between intestinal flora and intestinal macrophages in the environment. It provides potential targets for the metabolic diagnosis and treatment of CRC.

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.