Objective To review the changes of gut microbiota after bariatric surgery and the related mechanisms of improving metabolism. Method Domestic and international literatures in recent ten years on the changes of gut microbiota in bariatric surgery and the mechanisms of improving metabolism were collated and summarized. Result The common bariatric procedures performed to date were vertical sleeve gastrectomy (VSG) and laparoscopic Roux-en-Y gastric bypass (RYGB). The changes of gut microbiota vary in different surgical procedures, which were related to the changes of diet habits, gastrointestinal anatomy, gastrointestinal hormone levels and metabolic complications. The gut microbiota might improve the body metabolism by regulating the levels of short chain fatty acids, branched chain amino acids and bacterial endotoxin in the intestinal lumen. Conclusions Significant changes are found in gut microbiota after bariatric surgery, which may be involved in the improvement of body metabolism by regulating the level of bacterial endotoxin and microbial metabolite. However, more in-depth mechanisms need to be further clarified.
Primary sarcopenia (PS) is an age-related degenerative disorder characterized by progressive loss of skeletal muscle mass and function. This review delineates three mechanisms whereby gut dysbiosis drives PS pathogenesis: decreased secondary bile acids inhibit farnesoid X receptor signaling, thereby attenuating muscle protein synthesis; disrupted short-chain fatty acid metabolism weakens free fatty acid receptor 2/adenosine monophosphate-activated protein kinase signaling, aggravating proteolysis and mitochondrial dysfunction; gut barrier impairment activates the endotoxin–Toll-like receptor 4-mediated inflammatory cascade, accelerating ubiquitin-proteasome system activation. Interventional evidence confirms that microbiota-targeted therapies (probiotics regulating bile acid metabolism and prebiotics enhancing short-chain fatty acid production) effectively improve muscle function. By synthesizing molecular evidence of the “gut-muscle axis”, this review offers theoretical references for developing PS prevention and treatment strategies.
Gut microbiota plays an important role in development of diabetes with frailty. Therefore, it is of great significance to study the structural and functional characteristics of gut microbiota in Chinese with frailty. Totally 30 middle-aged and the aged participants in communities with diabetes were enrolled in this study, and their feces were collected. At the same time, we developed a metagenome analysis to explore the different of the structural and functional characteristics between diabetes with frailty and diabetes without frailty. The results showed the alpha diversity of intestinal microbiota in diabetes with frailty was lower. Collinsella and Butyricimonas were more abundant in diabetes with frailty. The functional characteristics showed that histidine metabolism, Epstein-Barr virus infection, sulfur metabolism, and biosynthesis of type Ⅱ polyketide products were upregulated in diabetes with frailty. Otherwise, butanoate metabolism and phenylalanine metabolism were down-regulated in diabetes with frailty. This research provides theoretical basic for exploring the mechanism of the gut microbiota on the occurrence and development of diabetes with frailty, and provides a basic for prevention and intervention of it.
There is a bidirectional association between tumor-associated macrophage (TAM) and colorectal cancer. Small molecular substances metabolized by colorectal cancer affect the reprogramming of TAM, and TAM in turn regulates the biological behavior of colorectal cancer cells by secreting small molecular substances, and promotes the progression of colorectal cancer. In addition, gut microbiota metabolites are closely related to TAM reprogramming, and intestinal flora imbalance leads to gut barrier damage, favoring bacterial translocation and causing chronic tumorigenic inflammation. Studying the reprogramming mechanism affecting TAM and its relationship with the occurrence and development of colorectal cancer may provide new ideas for the study of immunotherapy in patients with colorectal cancer. This article reviews the research progress of TAM in patients with colorectal cancer, aims to provide a reference for clinical research.
Objective To assess any potential associations between lung cancer and gut microbiota. Methods Mendelian randomization (MR) analysis was carried out by utilizing summary data from genome-wide association studies (GWAS) of the gut microbiota and lung cancer. The gut microbiota served as an exposure. Instrumental ariables (IVs) were identified from the GWAS of 18340 participants. The GWAS study of lung cancer from Europe served as an outcome, including 29 266 lung cancer patients and 56450 controls. We used the inverse-variance weighted (IVW) method as the primary analysis. Sensitivity analysis was used to test the reliability of MR analysis results. Results IVW results showed that Genus Parabacteroides (OR=1.258, 95%CI 1.034 to 1.531, P=0.022) and Phylum Bacteroidetes (OR=1.192, 95%CI 1.001 to 1.419, P=0.048) had a positive causal association with lung cancer, and there was a negative causal association between family Bifidobacteriaceae (OR=0.845, 95%CI 0.721 to 0.989, P=0.037) and order Bifidobacteriales (OR=0.865, 95%CI 0.721 to 0.989, P=0.037) with lung cancer. Sensitivity analysis showed no evidence of reverse causality, pleiotropy, and heterogeneity. Conclusion This study demonstrates that Genus Parabacteroides and Phylum Bacteroidetes are related to an increased risk of lung cancer, family Bifidobacteriaceae and order Bifidobacteriales can reduce the risk of lung cancer. Our thorough investigations provide evidence in favor of a potential causal relationship between a number of gut microbiota-taxa and lung cancer. To demonstrate how gut microbiota influences the development of lung cancer, further research is necessary.
As a heterogeneous disease characterized by changes in cardiac structure or function, cardiomyopathy has a significant impact on the quality of life of patients. And the gut microbiota, as the “second genome”, can regulate cardiac function through the “gut-heart axis”, providing a new perspective for the prevention and treatment of cardiomyopathy. This article summarizes the types and quantitative characteristics of gut microbiota in patients with cardiomyopathy. From the perspective of direct effects and indirect effects of metabolites such as short chain fatty acids, trimethylamine oxide, and bile acids, the mechanisms by which gut microbiota affects cardiomyopathy are explained. And the therapeutic effects of various gut microbiota regulation methods, such as dietary regulation, traditional Chinese medicine regulation, probiotics and prebiotics regulation on cardiomyopathy are explored, in order to provide reference for scientific regulation of gut microbiota in the prevention and treatment of cardiomyopathy.
Objective To analyze the causal relationship between gut microbiota and childhood asthma based on Mendelian randomization (MR). Methods The human gut microbiota dataset was downloaded from the MiBioGen database, and 196 known bacterial groups (9 phyla, 16 classes, 20 orders, 32 families, and 119 genera) were retained as exposure factors. Single nucleotide polymorphisms (SNPs) that were strongly correlated with exposure factors and independent of each other were selected as effective instrumental variables. A childhood asthma dataset with 3 025 patients and 135 449 controls was downloaded from the genome-wide association studies database as the outcome variable. Two-sample MR analysis was performed using inverse variance weighted, weighted median, MR-Egger, weighted model and simple model methods, respectively. The causal association between gut microbiota and childhood asthma was evaluated by odds ratio (OR). Sensitivity analysis was performed by leave-one-out method. Horizontal pleiotropy was tested by MR-Egger intercept test and MR-PRESSO global test, and Cochran’s Q test was used for heterogeneity. Results A total of 15 out of 196 gut microbiota groups were found to have a causal association (P<0.05) with the risk of childhood asthma, with a total of 181 SNPs included in the analysis. Inverse variance weighted analysis showed that Mollicutes [OR=1.42, 95% confidence interval (CI) (1.10, 1.83), P=0.007], Escherichia-Shigella [OR=1.39, 95%CI (1.02, 1.90), P=0.036], Oxalobacter [OR=1.30, 95%CI (1.10, 1.54), P=0.002], Ruminococcaceae UCG-009 [OR=1.34, 95%CI (1.09, 1.64), P=0.006] and Tenericutes [OR=1.42, 95%CI (1.10, 1.83), P=0.007] were significantly positively correlated with childhood asthma. Actinobacteria [OR=0.76, 95%CI (0.58, 0.99), P=0.042], Bifidobacteriaceae [OR=0.76, 95%CI (0.58, 0.98), P=0.035], Eubacterium nodatum group [OR=0.81, 95%CI (0.70, 0.94), P=0.007], Bifidobacterales [OR=0.76, 95%CI (0.58, 0.98), P=0.035] and Actinobacteria [OR=0.74, 95%CI (0.56, 0.99), P=0.040] were negatively correlated with childhood asthma. In addition, the results of leave-one-out sensitivity analysis were stable, MR-Egger intercept test and MR-PRESSO global test showed no horizontal pleiotropy, and Cochran’s Q test showed no heterogeneity. Conclusions There is a causal relationship between gut microbiota and childhood asthma. Mollicutes, Escherichia-Shigella, Oxalobacter, Ruminococcaceae UCG-009 and Tenericutes may increase the risk of childhood asthma. Actinobacteria, Bifidobacteriaceae, Eubacterium nodatum group, Bifidobacterales and Actinobacteria can reduce the risk of childhood asthma.
Objective To analyze the causal relationship between gut microbiota and tic disorder based on Mendelian randomization (MR). Methods A total of 196 known microbiota (9 phyla, 16 classes, 20 orders, 32 families, and 119 genera) in the human intestinal microbiota dataset downloaded from the MiBioGen database were selected as the exposure factors, and the dataset of tic disorder (finn-b-KRA_PSY_TIC) containing 172 patients and 218620 controls was downloaded from the genome-wide association study database as the outcome variable. Inverse variance weighted was used as the main analysis method, and the causal relationship between gut microbiota and tic disorder was evaluated using odds ratio (OR) and its 95% confidence interval (CI). Horizontal pleiotropy was tested by MR-Egger intercept and MR-PRESSO global test, heterogeneity was assessed by Cochran’s Q test, and sensitivity analysis was performed by leave-one-out method. Results Inverse variance weighted results showed that the Family Rhodospirillaceae [OR=0.398, 95%CI (0.191, 0.831), P=0.014], Order Rhodospirillales [OR=0.349, 95%CI (0.164, 0.743), P=0.006], and Parasutterella [OR=0.392, 95%CI (0.171, 0.898), P=0.027] had negative causal relationships with tic disorder. The Genus Lachnospira [OR=8.784, 95%CI (1.160, 66.496), P=0.035] and Candidatus Soleaferrea [OR=2.572, 95%CI (1.161, 5.695), P=0.020] had positive causal relationships with tic disorder. In addition, MR-Egger intercept and MR-PRESSO global test showed no horizontal pleiotropy, Cochran’s Q test showed no heterogeneity, and leave-one-out sensitivity analysis showed the results were stable. Conclusions A causal relationship exists between gut microbiota and tic disorder. The Family Rhodospirillaceae, Order Rhodospirillales, and Parasutterella are associated with a decreased risk of tic disorder, while the Genus Lachnospira and Candidatus Soleaverea can increase the risk of tic disorder.
ObjectiveTo investigate the causal relationship between gut microbiota and cholelithiasis using a two-sample Mendelian randomization method. MethodsThe genome-wide association studies (GWAS) data of gut microbiota from the MiBioGen study and the GWAS data of cholelithiasis from the FinnGen Biobank were utilized. Genetic variants significantly associated with the relative abundance of gut microbiota were identified as instrumental variables (IVs) based on a specified threshold. The inverse variance weighted (IVW) method was employed as the primary analytical approach, with results assessed based on the odds ratio (OR) and 95% confidence interval (CI). The robustness and reliability of the findings were ensured through quality control measures, including sensitivity analysis, assessment of heterogeneity, and evaluation for horizontal gene pleiotropy. ResultsClostridiumsensustricto1 [OR=1.160, 95%CI (1.023, 1.314), P=0.020], Coprococcus3 [OR=1.136, 95%CI (1.014, 1.272), P=0.028] and Peptococcus [OR=1.074, 95%CI (1.023, 1.128) , P=0.004] increased the risk of cholelithiasis. Bacilli [OR=0.897, 95%CI (0.818, 0.984), P=0.022], Family Ⅹ ⅢAD3011group [OR=0.908, 95%CI (0.830, 0.992), P=0.033] and Lactobacillales [OR=0.884, 95%CI (0.802, 0.974), P=0.013] were protective factors for cholelithiasis. ConclusionThe study has identified 6 kinds of specific gut microbiota that are causally linked to the development of cholelithiasis, providing new ideas for the diagnosis and treatment of cholelithiasis.
ObjectiveTo investigate the heterogeneity of gut microbiota between patients with solitary pulmonary nodules (SPN) and multiple pulmonary nodules (MPN), and to explore the intrinsic relationship between Traditional Chinese Medicine (TCM) constitution types and the intestinal microecology. MethodsA prospective study was conducted on 280 patients with pulmonary nodules enrolled between April 2022 and December 2024 from Hospital of Chengdu University of Traditional Chinese Medicine, Sichuan Cancer Hospital, Chengdu Integrated Traditional Chinese Medicine & Western Medicine Hospital. Among them, 118 (42.1%) were male and 162 (57.9%) were female, with a median age of 50 (42, 57) years. Based on imaging findings, patients were divided into a SPN group (n=65) and an MPN group (n=215). TCM constitution types were identified using a Constitution in Chinese Medicine Questionnaire. Fecal samples were collected for 16S rRNA sequencing. Bioinformatics analysis was employed to analyze inter-group differences in microbial community structure. The correlation between TCM constitutions and gut microbiota was examined using Procrustes analysis and Spearman correlation analysis. ResultsThe distribution of TCM constitution types between the two groups showed a statistically significant difference (P<0.05). The SPN group was predominantly characterized by the Qi-depression constitution, while the MPN group was more commonly associated with Yang-deficiency and Phlegm-dampness constitutions. Microbiota analysis revealed that the gut microbiota health index was significantly higher in the SPN group than in the MPN group (P<0.05), whereas the microbiota dysbiosis index showed the opposite pattern. Taxonomic analysis identified higher abundances of Ruminococcus_torques_group, Haemophilus, and Fusobacterium in the SPN group. The abundance of Leuconostoc was significantly increased in the MPN group. Procrustes analysis and Spearman correlation analysis indicated that in the SPN group, the Qi-depression constitution was positively correlated with Ruminococcus_torques_group and Bacteroides. In the MPN group, the Yang-deficiency constitution was negatively correlated with Faecalibacterium, while no statistically significant correlations were found between specific bacterial genera and the Phlegm-dampness or Qi-deficiency constitutions. ConclusionSPN and MPN exhibit significant heterogeneity in TCM constitutional tendencies and microecological characteristics. The abundance of specific bacterial genera may serve as potential biomarkers for distinguishing between SPN and MPN. The interaction between TCM constitutions and specific gut microbiota provides a theoretical basis for the precise TCM syndrome differentiation and microecological intervention in pulmonary nodules.