Trimethylamine N-oxide and kidney diseases: what do we know? / N-óxido de trimetilamina e doenças renais: o que sabemos?

Abstract In the human gut, there is a metabolically active microbiome whose metabolic products reach various organs and are used in the physiological activities of the body. When dysbiosis of intestinal microbial homeostasis occurs, pathogenic metabolites may increase and one of them is trimethyl amine-N-oxide (TMAO). TMAO is thought to have a role in the pathogenesis of insulin resistance, diabetes, hyperlipidemia, atherosclerotic heart diseases, and cerebrovascular events. TMAO level is also associated with renal inflammation, fibrosis, acute kidney injury, diabetic kidney disease, and chronic kidney disease. In this review, the effect of TMAO on various kidney diseases is discussed.

Resumo No intestino humano, existe um microbioma metabolicamente ativo cujos produtos metabólicos alcançam diversos órgãos e são utilizados nas atividades fisiológicas do corpo. Quando ocorre disbiose da homeostase microbiana intestinal, os metabólitos patogênicos podem aumentar, e um deles é o N-óxido de trimetilamina (TMAO). Acredita-se que o TMAO tenha um papel na patogênese da resistência à insulina, diabetes, hiperlipidemia, doenças cardíacas ateroscleróticas e eventos cerebrovasculares. O nível de TMAO também está associado à inflamação renal, fibrose, lesão renal aguda, doença renal diabética e doença renal crônica. Nesta revisão, discute-se o efeito do TMAO em diversas doenças renais.

The combination of berberine and cinnamon polyphenol can improve glucose metabolism in T2DM rats through Bas-TGR5-GLP-1 / 药学学报

Berberine (BBR) is the main pharmacological active ingredient of Coptidis, which has hypoglycemic effect, but its clinical application is limited due to its poor oral bioavailability. Polyphenols, derived from cinnamon, are beneficial for type 2 diabetes mellitus (T2DM). The combination of both may have an additive effect. The aim of this study was to investigate the hypoglycemic effect and mechanism of combined medication in diabetic rats. The modeling rats were randomly divided into 5 groups (berberine group, cinnamon group, combined group, metformin group, diabetic control group) and normal control group. The animal experiments were approved by the Animal Ethics Committee (approval number: HMUIRB2022003). The subjects were given orally, and the control group was given equal volume solvent and body weight was measured weekly. Thirty days after administration, oral glucose tolerance test and insulin sensitivity test were performed, and fasting blood glucose (FBG), glycated serum protein (GSP), and serum insulin (INS) levels were detected; high-throughput sequencing technology was used to detect intestinal microbiota structure; real-time quantitative PCR (RT-qPCR) and Western blot were used to detect G protein-coupled receptor 5 (TGR5) and glucagon-like peptide-1 (GLP-1) expression levels. The results showed that, compared with the diabetic control group, the levels of FBG (P < 0.01) and GSP (P < 0.01) in the combined group were lower, and the insulin resistance was improved, which was better than that in the berberine group. Combined treatment increased the relative abundance of Bacteroides, Prevotella and Lactobacillus, reversed the decrease in Lactobacillus in the berberine alone induction group, and the combination of the two could promote the expression of TGR5 and GLP-1. In summary, the combined application of cinnamon and berberine can regulate glucose metabolism better than the application of berberine alone. Berberine combined with cinnamon can improve the function of pancreatic islet β cells in diabetes mellitus type 2 rats by changing the intestinal microbiota, increasing the expression of TGR5 and GLP-1 proteins, and thereby better regulating glucose metabolism.

Mechanism of Flavonoids in Patriniae Herba in Affecting Occurrence and Development of Colorectal Cancer / 中国实验方剂学杂志

Colorectal cancer is a common malignant tumor in the digestive system， ranking third in incidence and second in the cause of death worldwide. In recent years， the incidence of colorectal cancer is on the rise， and the age of patients with colorectal cancer tends to be younger， with a heavy cancer burden. It is of great significance to prevent the occurrence， development， recurrence， and metastasis of colorectal cancer to reduce the incidence and mortality of colorectal cancer. Patriniae Herba has the effects of clearing heat， removing toxins， eliminating carbuncle， and discharging pus and shows good therapeutic efficacy on inflammatory bowel disease， digestive tract tumors， pelvic inflammation， gynecological tumor， and so on. Patriniae Herba is often used in the clinical treatment of colorectal cancer， but its mechanism of action is not clear. Modern studies have found that Patriniae Herba contains triterpenoids， saponins， iridoids， flavonoids， and other chemical components， with antioxidant， anti-tumor， anti-bacterial， and other pharmacological effects. The main anti-tumor components of Patriniae Herba are flavonoids. The analysis of network pharmacology and the spectrum-effect relationship has suggested that quercetin， luteolin， apigenin， isoorientin， and isovitexin play a major role in inhibiting the occurrence and development of colorectal cancer. In vivo and in vitro studies have shown that flavonoids in Patriniae Herba can play an anti-tumor role in various ways， such as preventing precancerous lesions of colorectal cancer， inhibiting the growth and proliferation of cancer cells， blocking cancer cell cycle， promoting cancer cell apoptosis， and reversing drug resistance of colorectal cancer. The oral availability of flavonoids is low. The gut is the main metabolic site of flavonoids in the body， its metabolic pathway is closely related to gut microbiota. This paper reviewed the anti-tumor mechanism of flavonoids and their influence on gut microbiota to provide a reference for further research on the mechanism of Patriniae Herba against colorectal cancer and its clinical application.

Connotation of Traditional Chinese Medicine in Treatment of Chronic Obstructive Pulmonary Disease by Regulating Gut Microbiota Based on "Lung and Large Intestine Being Interior-exterior Related" / 中国实验方剂学杂志

Chronic obstructive pulmonary disease （COPD） is a heterogeneous lung condition characterized by persistent and often progressive airflow obstruction， including airway abnormalities （e.g.， bronchitis and bronchiolitis） and chronic respiratory symptoms （e.g.， dyspnea， cough， and expectoration）. It is one of the leading causes of death worldwide. According to the theory of traditional Chinese medicine （TCM）， the lung and large intestine are interior-exterior related. Therefore， COPD can be treated from both the lung and intestine by the methods of tonifying and invigorating lung， spleen， and kidney， dispelling phlegm， and expelling stasis. Gut microbiota plays a key role in human immunity， nerve， and metabolism and may act on COPD by affecting the structures and functions of lung and intestine tissue and regulating lung inflammation and immunity. TCM can restore the balance of gut microbiota， which is conducive to the recovery from COPD. For example， the treatment method of tonifying lung and invigorating kidney can regulate gut microbiota， alleviate pulmonary and intestinal injuries， and improve lung immunity. The treatment methods of dispelling phlegm and expelling stasis can regulate gut microbiota and reduce pulmonary inflammation. According to the TCM theory of lung and large intestine being interior-exterior related， this review elaborates on the connotation of TCM in the treatment of COPD by regulating gut microbiota， aiming to provide new ideas for the clinical treatment of COPD via gut microbiota.

A Deep Insight into the Correlation Between Gut Dysbiosis and Alzheimer’s Amyloidopathy

Recent research has shown a strong correlation between gut dysbiosis and Alzheimer’s disease (AD). The purpose of this review is to investigate the relationship between gut dysbiosis, immune system activation, and the onset of AD and to examine current breakthroughs in microbiota-targeted AD therapeutics. A review of scientific literature was conducted to assess the correlation between gut dysbiosis and AD and the various factors associated. Gut dysbiosis produces an increase in harmful substances, such as bacterial amyloids, which makes the gut barrier and blood-brain barrier more permeable. This leads to the stimulation of immunological responses and an increase in cytokines such as interleukin-1? (IL-1?). As a result, gut dysbiosis accelerates the progression of AD. The review highlights the connection between gut dysbiosis and AD and the potential for microbiota-targeted therapies in AD treatment.

Potential relationship between Tourette syndrome and gut microbiome

Abstract Objective: In this article, the author aims to discuss and review the relationship between gut microbiota and Tourette syndrome, and whether the change in gut microbiota can affect the severity of Tourette syndrome. Sources: Literature from PubMed, Google Scholar, and China National Knowledge Infrastructure was mainly reviewed. Both original studies and review articles were discussed. The articles were required to be published as of May 2022. Summary of the findings: Current studies on the gut microbiome have found that the gut microbiome and brain seem to interact. It is named the brain-gut-axis. The relationship between the brain-gut axis and neurological and psychiatric disorders has been a topic of intense interest. Tourette syndrome is a chronic neurological disease that seriously affects the quality of life of children, and there appears to be an increase in Ruminococcaceae and Bacteroides in the gut of patients with Tourette syndrome. After clinical observation and animal experiments, there appear to be particular gut microbiota changes in Tourette syndrome. It provides a new possible idea for the treatment of Tourette syndrome. Probiotics and fecal microbial transplantation have been tried to treat Tourette syndrome, especially Tourette syndrome which is not sensitive to drugs, and some results have been achieved. Conclusions: The relationship between gut microbiota and Tourette syndrome and how to alleviate Tourette syndrome by improving gut microbiota are new topics, more in-depth and larger sample size research is still needed.

A doença de Alzheimer e sua relação com o eixo microbiota-intestino-cérebro / Alzheimer's disease and its relationship with the microbiota-gut-brain axis

ABSTRACT Background: Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease, characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. Several pathways enable bidirectional communication between the central nervous system (CNS), the intestine and its microbiota, constituting the microbiota-gut-brain axis. Objective: Review the pathophysiology of AD, relate it to the microbiota-gut-brain axis and discuss the possibility of using probiotics in the treatment and/or prevention of this disease. Methods: Search of articles from the PubMed database published in the last 5 years (2017 to 2022) structure the narrative review. Results: The composition of the gut microbiota influences the CNS, resulting in changes in host behavior and may be related to the development of neurodegenerative diseases. Some metabolites produced by the intestinal microbiota, such as trimethylamine N-oxide (TMAO), may be involved in the pathogenesis of AD, while other compounds produced by the microbiota during the fermentation of food in the intestine, such as D-glutamate and fatty acids short chain, are beneficial in cognitive function. The consumption of live microorganisms beneficial to health, known as probiotics, has been tested in laboratory animals and humans to evaluate the effect on AD. Conclusion: Although there are few clinical trials evaluating the effect of probiotic consumption in humans with AD, the results to date indicate a beneficial contribution of the use of probiotics in this disease.

RESUMO Contexto: A doença de Alzheimer (DA) é uma doença neurodegenerativa progressiva e irreversível, caracterizada pelo acúmulo de placas amiloides e emaranhados neurofibrilares no cérebro. Diversas vias possibilitam uma comunicação bidirecional entre o sistema nervoso central (SNC), o intestino e sua microbiota, constituindo o eixo microbiota-intestino-cérebro. Objetivo Revisar a fisiopatogenia da DA, relacioná-la com o eixo microbiota-intestino-cérebro e discutir sobre a possibilidade do uso de probióticos no tratamento e/ou prevenção desta doença. Métodos: Busca de artigos da base de dados PubMed publicados nos últimos 5 anos (2017 a 2022) para estruturar a revisão narrativa. Resultados A composição da microbiota intestinal influencia o SNC, resultando em modificações no comportamento do hospedeiro e pode estar relacionada com o desenvolvimento de doenças neurodegenerativas. Alguns metabólitos produzidos pela microbiota intestinal, como o N-óxido de trimetilamina (TMAO), podem estar envolvidos na patogênese da DA, enquanto, outros compostos produzidos pela microbiota durante a fermentação de alimentos no intestino, como o D-glutamato e os ácidos graxos de cadeia curta, são profícuos na função cognitiva. O consumo de microrganismos vivos benéficos à saúde, os probióticos, tem sido testado em animais de laboratório e humanos para avaliação do efeito na DA. Conclusão Embora haja poucos ensaios clínicos que avaliem o efeito do consumo de probióticos em humanos com DA, os resultados até o momento indicam uma contribuição benéfica do uso de probióticos nesta doença.

Assessing multiple factors affecting the gut microbiome structure of very preterm infants

The composition and diversity of the gut microbiota are essential for the health and development of the immune system of infants. However, there is limited information on factors that influence the gut microbiota of very preterm infants. In this study, we analyzed factors that affect the gut microbiota of very preterm infants. The stool samples from 64 very preterm infants with a gestational age less than 32 weeks were collected for 16S rRNA gene sequencing. The infants were divided according to the delivery mode, antibiotic use during pregnancy, and feeding methods. The abundance of Proteobacteria was high in both cesarean (92.7%) and spontaneous (55.5%) delivery groups and then shifted to Firmicutes after the first week of birth. In addition, Proteobacteria was also the dominant phylum of infant gut microbiome for mothers with antibiotic use, with more than 50% after the first week of birth. In comparison, the dominant phylum for mothers without antibiotic use was Firmicutes. Proteobacteria level was also high in breastfeeding and mixed-feeding groups, consisting of more than 90% of the community. By contrast, Proteobacteria was the dominant phylum at the first week of birth but then shifted to Firmicutes for the formula-fed group. The alterations of gut microbiota in infants can affect their health condition during growth. This study confirmed that the different feeding types, delivery modes, and use of antibiotics during pregnancy can significantly affect the composition of the gut microbiota of very preterm infants.

Structural mechanism of a dual-functional enzyme DgpA/B/C as both a C-glycoside cleaving enzyme and an O- to C-glycoside isomerase

The C-glycosidic bond that connects the sugar moiety with aglycone is difficult to be broken or made due to its inert nature. The knowledge of C-glycoside breakdown and synthesis is very limited. Recently, the enzyme DgpA/B/C cascade from a human intestinal bacterium PUE was identified to specifically cleave the C-glycosidic bond of puerarin (daidzein-8-C-glucoside). Here we investigated how puerarin is recognized and oxidized by DgpA based on crystal structures of DgpA with or without substrate and biochemical characterization. More strikingly, we found that apart from being a C-glycoside cleaving enzyme, DgpA/B/C is capable of efficiently converting O- to C-glycoside showing the activity as a structure isomerase. A possible mechanistic model was proposed dependently of the simulated complex structure of DgpB/C with 3″-oxo-daidzin and structure-based mutagenesis. Our findings not only shed light on understanding the enzyme-mediated C-glycosidic bond breakage and formation, but also may help to facilitate stereospecific C-glycoside synthesis in pharmaceutical industry.

Isolation of a foodborne Bacillus cereus strain and its effect on intestinal mucosal immunity-associated factors and gut microbial community in mice / 生物工程学报

Bacillus cereus is a common foodborne pathogen. Accidently eating food contaminated by B. cereus will cause vomiting or diarrhea, and even death in severe cases. In the present study, a B. cereus strain was isolated from spoiled rice by streak culture. The pathogenicity and drug resistance of the isolated strain were analyzed by drug sensitivity test and PCR amplification of virulence-associated gene respectively. Cultures of the purified strain were injected intraperitoneally into mice to examine their effects on intestinal immunity-associated factors and gut microbial communities, to provide references for the pathogenic mechanism and medication guidance of these spoilage microorganisms. The results showed that the isolated B. cereus strain was sensitive to norfloxacin, nitrofurantoin, tetracycline, minocycline, ciprofloxacin, spectinomycin, clindamycin, erythrocin, clarithromycin, chloramphenicol, levofloxacin, and vancomycin, but resistant to bactrim, oxacillin and penicillin G. The strain carries seven virulence-associated genes including hblA, hblC, hblD, nheA, nheB, nheC and entFM, which are involved in diarrhea-causing toxins production. After infecting mice, the isolated B. cereus strain was found to cause diarrhea in mice, and the expression levels of immunoglobulins and inflammatory factors in the intestinal mucosae of the challenged mice were significantly up-regulated. Gut microbiome analysis showed that the composition of gut microbial community in mice changed after infection with B. cereus. The abundance of the uncultured_bacterium_f_Muribaculaceae in Bacteroidetes, which is a marker of body health, was significantly decreased. On the other hand, the abundance of uncultured_bacterium_f_Enterobacteriaceae, which is an opportunistic pathogen in Proteobacteria and a marker of dysbacteriosis, was significantly increased and was significantly positively correlated with the concentrations of IgM and IgG. These results showed that the pathogenic B. cereus carrying diarrhea type virulence-associated gene can activate the immune system by altering the composition of gut microbiota upon infection.

Gut dysbiosis, inflammation and type 2 diabetes in mice using synthetic gut microbiota from diabetic humans / Disbiose intestinal, inflamação e diabetes tipo 2 em camundongos usando microbiota intestinal sintética de humanos diabéticos

Abstract The study was aimed to assess impact of high fat diet (HFD) and synthetic human gut microbiota (GM) combined with HFD and chow diet (CD) in inducing type-2 diabetes (T2D) using mice model. To our knowledge, this is the first study using selected human GM transplantation via culture based method coupled dietary modulation in mice for in vivo establishment of inflammation leading to T2D and gut dysbiosis. Twenty bacteria (T2D1-T2D20) from stool samples of confirmed T2D subjects were found to be morphologically different and subjected to purification on different media both aerobically and anerobically, which revealed seven bacteria more common among 20 isolates on the basis of biochemical characterization. On the basis of 16S rRNA gene sequencing, these seven isolates were identified as Bacteroides stercoris (MT152636), Lactobacillus acidophilus (MT152637), Lactobacillus salivarius (MT152638), Ruminococcus bromii (MT152639), Klebsiella aerogenes (MT152640), Bacteroides fragilis (MT152909), Clostridium botulinum (MT152910). The seven isolates were subsequently used as synthetic gut microbiome (GM) for their role in inducing T2D in mice. Inbred strains of albino mice were divided into four groups and were fed with CD, HFD, GM+HFD and GM+CD. Mice receiving HFD and GM+modified diet (CD/HFD) showed highly significant (P<0.05) increase in weight and blood glucose concentration as well as elevated level of inflammatory cytokines (TNF-α, IL-6, and MCP-1) compared to mice receiving CD only. The 16S rRNA gene sequencing of 11 fecal bacteria obtained from three randomly selected animals from each group revealed gut dysbiosis in animals receiving GM. Bacterial strains including Bacteroides gallinarum (MT152630), Ruminococcus bromii (MT152631), Lactobacillus acidophilus (MT152632), Parabacteroides gordonii (MT152633), Prevotella copri (MT152634) and Lactobacillus gasseri (MT152635) were isolated from mice treated with GM+modified diet (HFD/CD) compared to strains Akkermansia muciniphila (MT152625), Bacteriodes sp. (MT152626), Bacteroides faecis (MT152627), Bacteroides vulgatus (MT152628), Lactobacillus plantarum (MT152629) which were isolated from mice receiving CD/HFD. In conclusion, these findings suggest that constitution of GM and diet plays significant role in inflammation leading to onset or/and possibly progression of T2D. .

Resumo O estudo teve como objetivo avaliar o impacto da dieta rica em gordura (HFD) e da microbiota intestinal humana sintética (GM) combinada com HFD e dieta alimentar (CD) na indução de diabetes tipo 2 (T2D) usando modelo de camundongos. Para nosso conhecimento, este é o primeiro estudo usando transplante de GM humano selecionado através do método baseado em cultura acoplada à modulação dietética em camundongos para o estabelecimento in vivo de inflamação que leva a T2D e disbiose intestinal. Vinte bactérias (T2D1-T2D20) de amostras de fezes de indivíduos T2D confirmados verificaram ser morfologicamente diferentes e foram submetidas à purificação em meios diferentes aerobicamente e anaerobicamente, o que revelou sete bactérias mais comuns entre 20 isolados com base na caracterização bioquímica. Com base no sequenciamento do gene 16S rRNA, esses sete isolados foram identificados como Bacteroides stercoris (MT152636), Lactobacillus acidophilus (MT152637), Lactobacillus salivarius (MT152638), Ruminococcus bromii (MT152639), Klebsiella aerogenides (MT152640), Bacteroides fragilis (MT152909), Clostridium botulinum (MT152910). Esses sete isolados foram, posteriormente, usados ​​como microbioma intestinal sintético (GM) por seu papel na indução de T2D em camundongos. Linhagens consanguíneas de camundongos albinos foram divididas em quatro grupos e foram alimentadas com CD, HFD, GM + HFD e GM + CD. Camundongos que receberam a dieta modificada com HFD e GM + (CD / HFD) mostraram um aumento altamente significativo (P < 0,05) no peso e na concentração de glicose no sangue, bem como um nível elevado de citocinas inflamatórias (TNF-α, IL-6 e MCP-1) em comparação com os ratos que receberam apenas CD. O sequenciamento do gene 16S rRNA de 11 bactérias fecais obtidas de três animais selecionados aleatoriamente de cada grupo revelou disbiose intestinal em animais que receberam GM. Cepas bacterianas, incluindo Bacteroides gallinarum (MT152630), Ruminococcus bromii (MT152631), Lactobacillus acidophilus (MT152632), Parabacteroides gordonii (MT152633), Prevotella copri (MT152634) e Lactobacillus Gasseri (MT152635D), foram tratadas com dieta modificada / CD) em comparação com as linhagens Akkermansia muciniphila (MT152625), Bacteriodes sp. (MT152626), Bacteroides faecis (MT152627), Bacteroides vulgatus (MT152628), Lactobacillus plantarum (MT152629), que foram isoladas de camundongos recebendo CD / HFD. Em conclusão, esses resultados sugerem que a constituição de GM e dieta desempenham papel significativo na inflamação levando ao início ou/e possivelmente à progressão de T2D.

Study on the relationship between intestinal flora analysis and CD4 +T lymphocyte subsets in patients with systemic lupus erythematosus / 中华风湿病学杂志

Objective:To explore the characteristics of intestinal microbiota in patients with systemic lupus erythematosus (SLE), and further explore the relationship between microbiota and CD4 +T lymphocyte subsets and disease activity. Methods:Fecal samples were collected from 96 patients with SLE, and 96 sex- and age-matched healthy controls (HCs). The gut microbiota were investigated via 16s rRNA sequencing. Flow cytometry was used to detect peripheral CD4 +T lymphocyte subsets of Th1, Th2, Th17 and Treg cells. Indicators of disease activity such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement C3 and C4, Systemic lupus erythematosus disease activity index(SLEDAI) for each patient were recorded. Differential abundance analysis was carried out using the edgeR algorithm. The Wilcoxon rank-sum test was used to compare alpha diversity indices, bacterial abundances, and the F/B ratio between groups. R (version 4.0.1) was used for comparative statistics, and Pearson′s correlation analysis was used to assess the correlations between the relative abundances of bacterial genera and serum levels of ESR, CRP, C3 and C4 in the samples. Results:The alpha estimators of richness (ACE and Chao 1) were significantly reduced in SLE feces samples compared with those of HCs ( P<0.01). Bacterial diversity estimators, including the Shannon ( P<0.01) and Simpson′s ( P<0.01) indices, were also significantly lower in SLE. Significant differences in gut microbiota composition between SLE and HCs were found using the edgeR algorithm. Compared with HC, 24 species of bacteria were significantly different in SLE patients at the genus level ( P<0.05). Moreover, there was a significant positive correlation between CRP and Coprococcus ( r=0.30, P=0.014), C4 and Corynebacterium ( r=0.31, P=0.013) and Faecalibacterium( r=0.25, P=0.048), Hemoglobin and Morganella( r=0.41, P=0.001), as well as SLIDA and Corynebacterium( r=0.25, P=0.047). In terms of lymphocyte subsets, there was significant positive correlation between B cells, Treg cells and Eubacterium eligens group, as well as CD8 +T, CD4 +T, NK cells and Corynebacterium. In additional, Th1 was positively correlated with Shigella Escherichia coli ( r=0.52, P=0.008), and Th2 was positively correlated with Dielma ( r=0.51, P<0.001). Conclusion:The abundance and diversity of intestinal flora in SLE patients were significantly reduced, and the differentially expressed bacteria were closely related to the CD4 +T lymphocyte subsets and disease activity indicators of patients.

Alterations of gut microbiota composition and cogni-tive behavior in APP/PS1/tau triple-transgenic mouse model of Alzheimer's disease / 中国药理学与毒理学杂志

OBJECTIVE Alzheimer's disease(AD)is a progressive neurological disease.Given the important role of gut microbiota composition in AD pathology,the observed perturbation in the microbiota composition and diversity may serve as the mechanisms underlying age-dependent APP/PS1/tau triple-transgenic mouse(3×Tg-AD)mice amyloid deposition and memory deficits.Here-in,we intended to investigate the gut microbiota and as-sessed its relationship with the triggering and develop-ment of cognitive impairment of AD.METHODS This study involves the comparative assessment of spatial learning,amyloid β-protein(Aβ)accumulation,and fecal microbiota alterations in 3×Tg-AD mice from three age groups:AD asymptomatic stage(3 m),presymptomatic stage(6 m),and the symptomatic stage of AD(9 m).RE-SULTS We demonstrate that spatial memory deficits,brain Aβ accumulation,and weight gain in 3×Tg-AD mice gradually appear after 6 months of age.However,the total gut bacterial counts underwent changes from 3 to 6 months of age and were further altered at 9 months of age.Importantly,changes in gut bacteria abundance of Desulfobacterota and Actinobacteriota phylain 6-month-old mice preceded apparent spatial memory deficits.CONCLUSION Changes in the gut microbial community are one of the mechanisms of early AD pathology.

Research progress of sepsis-associated acute kidney injury based on Gut-Kidney axis / 中华危重病急救医学

Sepsis-associated acute kidney injury (SA-AKI), as a common renal dysfunction in sepsis, has become one of the major diseases threatening human health with increasing morbidity and mortality. Based on the theory of "gut-kidney axis", the intestine and kidney have a two-way synergistic relationship in sepsis. Intestinal flora imbalance, endogenous metabolite imbalance, and impaired endothelial barrier integrity are involved in renal injury, and the increase of renal inflammatory mediators interferes with the composition of intestinal microorganisms. Therefore, understanding the intestinal-renal crosstalk mechanism of SA-AKI will help to provide a potential basis for new treatment strategies for SA-AKI.

Regulatory effects of umbilical cord mesenchymal stem cells and their conditioned medium on gut microbiota of septic mice / 中华危重病急救医学

Objective:To investigate and compare the regulatory effects of umbilical cord mesenchymal stem cells (MSC) and their conditioned medium (MSC-CM) on gut microbiota of septic mice.Methods:Twenty-eight six-to-eight-week-old female C57BL/6J mice were randomly divided into sham operation group (Sham group), sepsis model group (CLP group), sepsis+MSC treatment group (CLP+MSC group) and sepsis+MSC-CM treatment group (CLP+MSC-CM group), with seven mice in each group. The septic mouse model was established by cecal ligation and puncture (CLP). In Sham group, CLP were not performed, and other operations were the same as CLP group. Mice in the CLP+MSC group and CLP+MSC-CM group received 0.2 mL 1×10 6 MSC or 0.2 mL concentrated MSC-CM via intraperitoneal injection 6 hours after CLP, respectively. Sham group and CLP group were given 0.2 mL sterile phosphate buffer saline (PBS) via intraperitoneal injection. Histopathological changes were evaluated by hematoxylin-eosin (HE) staining and colon length. Levels of inflammatory factors in serum were detected by enzyme-linked immunosorbent assay (ELISA). Phenotype of peritoneal macrophages was analyzed by flow cytometry, and the gut microbiota was analyzed via 16S rRNA sequencing. Results:Compared with Sham group, significant inflammatory injury in lung and colon was observed, and shorter colon was detected in CLP group (cm: 6.00±0.26 vs. 7.11±0.09), the level of inflammatory cytokine interleukin-1β (IL-1β) in serum was significantly increased (ng/L: 432.70±17.68 vs. 353.70±17.01), the proportion of F4/80 + peritoneal macrophages was increased [(68.25±3.41)% vs. (50.84±4.98)%], while the ratio of F4/80 +CD206 + anti-inflammatory peritoneal macrophages was decreased [(45.25±6.75)% vs. (66.66±3.36)%]. The α diversity sobs index of gut microbiota was downregulated significantly (118.50±23.25 vs. 255.70±6.87), the structure of species composition was altered, and the relative abundance of functional gut microbiota related to transcription, secondary metabolites biosynthesis, transport and catabolism, carbohydrate transport and metabolism, and signal transduction were decreased significantly in CLP group (all P < 0.05). Compared with CLP group, upon MSC or MSC-CM treatment, the pathological injury in lung and colon was alleviated to varying extent, the length of colon was increased (cm: 6.53±0.27, 6.87±0.18 vs. 6.00±0.26), the level of IL-1β in serum was downregulated (ng/L: 382.10±16.93, 343.20±23.61 vs. 432.70±17.68), the ratio of F4/80 + peritoneal macrophages was decreased [(47.65±3.93)%, (48.68±2.51)% vs. (68.25±3.41)%], the ratio of F4/80 +CD206 + anti-inflammatory peritoneal macrophages was increased [(52.73±5.02)%, (66.38±4.73)% vs. (45.25±6.75)%], and the α diversity sobs index of gut microbiota was increased (182.50±16.35, 214.00±31.18 vs. 118.50±23.25), and the effects of MSC-CM were more significant (all P < 0.05). At the same time, species composition of gut microbiota was rebuilt, and a tendency of increase in relative abundance of functional gut microbiota was observed upon MSC and MSC-CM treatment. Conclusion:Both MSC and MSC-CM could alleviate inflammatory injury in tissues, and showed regulatory effects on gut microbiota in septic mouse model, moreover, MSC-CM exhibited superior advantages over MSC.

The correlation between intestinal flora and glucose metabolism during pregnancy and the research progress on the application of probiotics / 中华临床营养杂志

Gut microbiota is the microbial community that resides on the surface of human intestinal mucosa. During normal pregnancy, the composition of gut microbiota may change dynamically with the progress of pregnancy. Gestational diabetes mellitus (GDM) is a common complication of pregnancy, which can affect maternal and neonatal intestinal flora, and affect the long-term glucose metabolism of mothers and infants through exacerbating insulin resistance and promoting inflammatory response. Adjustment of dietary structure and application of probiotics may regulate intestinal microbiota and improve maternal and neonatal glucose metabolism in GDM. Here we reviewed the correlation between intestinal flora and glucose metabolism during pregnancy, and discussed the effects of diet and probiotics on gut microbiota.

Radix Paeoniae Alba attenuates Radix Bupleuri-induced hepatotoxicity by modulating gut microbiota to alleviate the inhibition of saikosaponins on glutathione synthetase / 药物分析学报

Radix Bupleuri(RB)is commonly used to treat depression,but it can also lead to hepatotoxicity after long-term use.In many anti-depression prescriptions,RB is often used in combination with Radix Paeoniae Alba(RPA)as an herb pair.However,whether RPA can alleviate RB-induced hepatotoxicity remain unclear.In this work,the results confirmed that RB had a dose-dependent antidepressant effect,but the optimal antidepressant dose caused hepatotoxicity.Notably,RPA effectively reversed RB-induced hepatotoxicity.Afterward,the mechanism of RB-induced hepatotoxicity was confirmed.The results showed that saiko-saponin A and saikosaponin D could inhibit GSH synthase(GSS)activity in the liver,and further cause liver injury through oxidative stress and nuclear factor kappa B(NF-KB)/NOD-like receptor thermal protein domain associated protein 3(NLRP3)pathway.Furthermore,the mechanisms by which RPA attenuates RB-induced hepatotoxicity were investigated.The results demonstrated that RPA increased the abundance of intestinal bacteria with glycosidase activity,thereby promoting the conversion of saikosaponins to sai-kogenins in vivo.Different from saikosaponin A and saikosaponin D,which are directly combined with GSS as an inhibitor,their deglycosylation conversion products saikogenin F and saikogenin G exhibited no GSS binding activity.Based on this,RPA can alleviate the inhibitory effect of saikosaponins on GSS activity to reshape the liver redox balance and further reverse the RB-induced liver inflammatory response by the NF-κB/NLRP3 pathway.In conclusion,the present study suggests that promoting the conversion of saikosa-ponins by modulating gut microbiota to attenuate the inhibition of GSS is the potential mechanism by which RPA prevents RB-induced hepatotoxicity.

Gut microbiome characteristics in patients with type 2 diabetes mellitus of Dongxiang Group in Gansu province / 中国医师进修杂志

Objective:To investigate the region-specific characteristics of the gut microbiota and evaluate the association of speci?c gut microbes with type 2 diabetes mellitus (T2DM) from the Dongxiang Group in Gansu province, Northwest China.Methods:Fifty-three participants who was born in Dongxiang Autonomous County (Gansu Province) from April 2020 to January 2021 were enrolled, including 25 patients with T2DM recruited from the outpatient departments of internal medicine at The People′s Hospital of Dongxiang County(T2DM group) and 28 healthy controls recruited from the health screening center (HC group). Gut microbiome composition was analyzed using a 16S ribosomal RNA gene-based sequencing protocol.Results:A total of 936 operational taxonomic units (OTU) were obtained in the two groups. Of note, the HC and T2DM groups had 633 OTU in common. The alpha and beta diversity were different between the two groups ( P<0.05). Shannon index was significantly higher than that in the HC group, and Simpson index was significantly lower than that in the HC group, displacement multivariate analysis of variance was used to compare β diversity between the two groups, and the difference was statistically significant ( P<0.05). At the Phylum level, firmicutes and actinomycetes in T2DM group were significantly higher than those in the HC group (37.97% vs. 22.89%, 5.09% vs. 2.08%), and the differences were statistically significant ( P<0.05). The abundance of Bacteroidetes was significantly decreased (68.00% in T2DM group and 49.75% in HC group), and the difference was statistically significant ( P<0.05). At the genus level, there were 20 genera statistically significant differences between the two groups. The abundance of Bifidobacterium, Escherichia, Shigella, and Tyzzerella_4 levels were significantly increased in the T2DM group, but Prevotella_9, Erysipelotrichaceae_UCG-003, and Roseburia levels were significantly decreased in the T2DM group compared to those in the HC group. Conclusions:There is a significant difference in the gut microbiota between patients with T2DM and healthy individuals of the Dongxiang group in Northwest China. So as to preliminary exploration the intestinal flora characteristics of T2DM in the Dongxiang group.The findings of this study provide a theoretical basis for the prevention and control of T2DM in Dongxiang group in the future.

Research progress on the relationship between gut microbiota and male infertility / 现代泌尿外科杂志

With the decline in male fertility in recent years, infertility has become an urgent global problem to be solved. Existing evidence shows that gut microbiota has an important impact on male reproductive health, and gut microbiota disorder can affect spermatogenesis by inducing inflammation, metabolic disorder and endocrine disruption. This paper systematically reviews the relevant research progress in this field, focusing on the impact of gut microbiota disorder on male reproductive ability from the aspects of gut microbiota and spermatogenesis, gut microbiota and sex hormone metabolism, effects of fecal microbiota transplantation and dietary regulation on male reproductive function, and discusses the future research directions of gut micro-biota and male infertility.

Relationship between gut microbiota and substance addiction and its research progress / 西安交通大学学报(医学版)

Microbiota is the entire collection of microorganisms in a specific niche, such as the human gut. It impacts almost all organ systems and is related to disease resistance and susceptibility of the host. The microbiome refers to all of the genetic material within a microbiota. Microbiota is studied by means of sequencing specific genes or metagenomes; analyzing the species and their abundance and function; and determining the structure, diversity, evolutionary relationships, biological and medical significance, and their interactions with the environment of the microbiota. Human gut microbiota refers to that living in the human intestinal tract, including bacteria, fungi and viruses (bacteriophages). Current studies show that gut microbiota is closely related to human health, and its influence scope is far beyond the digestive system, but also involves the immune system, cardiovascular system, nervous system and other aspects. Substance addiction, a chronic recurrent brain disease, is characterized by persistent craving for addictive substances and forced drug use, which can cause changes in gut microbiota. We intend to discuss the relationship of gut microbiota with alcohol, cocaine, opioids, methamphetamine and other addictive substances, indicating that intervention in gut microbiota, which affects the structure and function of the brain, may become a new way to treat substance addiction.