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European Journal of Nuclear Medicine... Apr 2023Radioactive iodine (I) therapy is a conventional post-surgery treatment widely used for papillary thyroid carcinoma (PTC). Since I is orally administered, we hypothesize...
PURPOSE
Radioactive iodine (I) therapy is a conventional post-surgery treatment widely used for papillary thyroid carcinoma (PTC). Since I is orally administered, we hypothesize that it may affect gut microbiome. This study aims to investigate alterations of intestinal microbiome caused by I therapy in PTC patients and explore its association with response to I therapy.
METHODS
Fecal samples of 60 PTC patients pre- and post-I therapy were collected to characterize the I therapy-induced gut microbiota alterations using 16S rRNA gene sequencing. According to the inclusion criteria, sequence data of 40 out of the 60 patients, divided into excellent response (ER) group and non-excellent response (NER) group, were recruited to investigate the possible connection between gut microbiota and response to I therapy. Multivariate binary logistic regression was employed to construct a predictive model for response to I therapy.
RESULTS
Microbial richness, diversity, and composition were tremendously altered by I therapy. A significant decline of Firmicutes to Bacteroides (F/B) ratio was observed post-I therapy. I therapy also led to changes of gut microbiome-related metabolic pathways. Discrepancies in β diversity were found between ER and NER groups both pre- and post-I therapy. Furthermore, a predictive model for response to I therapy with a p value of 0.003 and an overall percentage correct of 80.0% was established, with three variables including lymph node metastasis, relative abundance of g_Bifidobacterium and g_Dorea. Among them, g_Dorea was identified to be an in independent predictor of response to I therapy (p = 0.04).
CONCLUSION
For the first time, the present study demonstrates the gut microbial dysbiosis caused by I therapy in post-surgery PTC patients and reveals a previously undefined role of gut microbiome as predictor for I ablation response. G_Dorea and g_Bifidobacterium may be potential targets for clinical intervention to improve response to I in post-operative PTC patients.
TRIAL REGISTRATION
ChiCTR2100048000. Registered 28 June 2021.
Topics: Humans; Gastrointestinal Microbiome; Iodine Radioisotopes; Thyroid Cancer, Papillary; RNA, Ribosomal, 16S; Thyroid Neoplasms
PubMed: 36512067
DOI: 10.1007/s00259-022-06072-5 -
Pathogens (Basel, Switzerland) Jul 2022is an anaerobic Gram-positive and spore-forming bacterium. The majority of strains produce two toxins, A and B, associated with the development of acute diarrhea... (Review)
Review
is an anaerobic Gram-positive and spore-forming bacterium. The majority of strains produce two toxins, A and B, associated with the development of acute diarrhea and/or colitis. In this review, two situations are distinguished: infection (CDI) and asymptomatic colonization (AC). The main objective of this review is to explore the available data related to the link between the gut microbiota and the development of CDI. The secondary aim is to provide more information on why some people colonized with toxigenic develop an infection while others show no signs of disease. Several factors, such as the use of antibiotics and proton pump inhibitors, hospitalization, and age, predispose individuals to colonization and/or infection. The gut microbiota of people with AC showed decreased abundances of , , , , , , and . The gut microbiota of people suffering from CDI showed reductions in the abundances of , , spp., spp., spp., spp., spp., spp., spp. and spp., in comparison with healthy people. Furthermore, increases in the abundances of and were associated with infection.
PubMed: 35890026
DOI: 10.3390/pathogens11070781 -
Ambio May 2023Mercury (Hg) is a chemical of health concern worldwide that is now being acted upon through the Minamata Convention. Operationalizing the Convention and tracking its... (Review)
Review
Mercury (Hg) is a chemical of health concern worldwide that is now being acted upon through the Minamata Convention. Operationalizing the Convention and tracking its effectiveness requires empathy of the diversity and variation of mercury exposure and risk in populations worldwide. As part of the health plenary for the 15th International Conference on Mercury as a Global Pollutant (ICMGP), this review paper details how scientific understandings have evolved over time, from tragic poisoning events in the mid-twentieth century to important epidemiological studies in the late-twentieth century in the Seychelles and Faroe Islands, the Arctic and Amazon. Entering the twenty-first century, studies on diverse source-exposure scenarios (e.g., ASGM, amalgams, contaminated sites, cosmetics, electronic waste) from across global regions have expanded understandings and exemplified the need to consider socio-environmental variables and local contexts when conducting health studies. We conclude with perspectives on next steps for mercury health research in the post-Minamata Convention era.
Topics: Humans; Arctic Regions; Denmark; Environmental Pollutants; Mercury; Environmental Exposure
PubMed: 36790578
DOI: 10.1007/s13280-023-01831-6 -
Nutrients Feb 2023Roux-en-Y Gastric bypass (RYGB) promotes improvement in type 2 diabetes (T2D) shortly after surgery, with metabolic mechanisms yet to be elucidated. This study aimed to...
Roux-en-Y Gastric bypass (RYGB) promotes improvement in type 2 diabetes (T2D) shortly after surgery, with metabolic mechanisms yet to be elucidated. This study aimed to investigate the relationship between food intake, tryptophan metabolism, and gut microbiota on the glycemic control of obese T2D women after RYGB surgery. Twenty T2D women who underwent RYGB were evaluated before and three months after surgery. Food intake data were obtained by a seven-day food record and a food frequency questionnaire. Tryptophan metabolites were determined by untargeted metabolomic analysis, and the gut microbiota was determined by 16S rRNA sequencing. The glycemic outcomes were fasting blood glucose, HbA1C, HOMA-IR, and HOMA-beta. Linear regression models were applied to assess the associations between the changes in food intake, tryptophan metabolism, and gut microbiota on glycemic control after RYGB. All variables changed after RYGB ( < 0.05), except for tryptophan intake. Jointly, the variation in red meat intake, plasma indole-3-acetate, and was associated with postoperative HOMA-IR {R 0.80, R adj 0.74; < 0.01}. Red meat intake decreased three months after bariatric surgery while indole-3-acetate and increased in the same period. These combined variables were associated with better insulin resistance in T2D women after RYGB.
Topics: Humans; Female; Gastric Bypass; Insulin Resistance; Diabetes Mellitus, Type 2; RNA, Ribosomal, 16S; Tryptophan; Red Meat; Acetates; Indoles; Blood Glucose; Insulin; Obesity, Morbid
PubMed: 36904185
DOI: 10.3390/nu15051185 -
Biomolecules Aug 2021Manganese (Mn) is an essential metal, which at high exposures causes neurotoxic effects and neurodegeneration. The neurotoxic effects of Mn are mediated by... (Review)
Review
Manganese (Mn) is an essential metal, which at high exposures causes neurotoxic effects and neurodegeneration. The neurotoxic effects of Mn are mediated by neuroinflammation, oxidative and endoplasmic reticulum stress, mitochondrial dysfunction, and other mechanisms. Recent findings have demonstrated the potential impact of Mn overexposure on gut microbiota dysbiosis, which is known to contribute to neurodegeneration via secretion of neuroactive and proinflammatory metabolites. Therefore, in this review, we discuss the existing data on the impact of Mn exposure on gut microbiota biodiversity, bacterial metabolite production, and gut wall permeability regulating systemic levels. Recent data have demonstrated that Mn exposure may affect gut microbiota biodiversity by altering the abundance of Shiegella, Ruminococcus, Dorea, Fusicatenibacter, Roseburia, Parabacteroides, Bacteroidetes, Firmicutes, Ruminococcaceae, Streptococcaceae, and other bacterial phyla. A Mn-induced increase in Bacteroidetes abundance and a reduced Firmicutes/Bacteroidetes ratio may increase lipopolysaccharide levels. Moreover, in addition to increased systemic lipopolysaccharide (LPS) levels, Mn is capable of potentiating LPS neurotoxicity. Due to the high metabolic activity of intestinal microflora, Mn-induced perturbations in gut microbiota result in a significant alteration in the gut metabolome that has the potential to at least partially mediate the biological effects of Mn overexposure. At the same time, a recent study demonstrated that healthy microbiome transplantation alleviates Mn-induced neurotoxicity, which is indicative of the significant role of gut microflora in the cascade of Mn-mediated neurotoxicity. High doses of Mn may cause enterocyte toxicity and affect gut wall integrity through disruption of tight junctions. The resulting increase in gut wall permeability further promotes increased translocation of LPS and neuroactive bacterial metabolites to the systemic blood flow, ultimately gaining access to the brain and leading to neuroinflammation and neurotransmitter imbalance. Therefore, the existing data lead us to hypothesize that gut microbiota should be considered as a potential target of Mn toxicity, although more detailed studies are required to characterize the interplay between Mn exposure and the gut, as well as its role in the pathogenesis of neurodegeneration and other diseases.
Topics: Animals; Gastrointestinal Microbiome; Humans; Immunity; Manganese; Metabolome; Nerve Degeneration; Neurotoxins
PubMed: 34572505
DOI: 10.3390/biom11091292 -
Indian Journal of Gastroenterology :... Feb 2024Inflammatory bowel diseases (IBD) are chronic inflammatory gut disorders, majorly classified as ulcerative colitis and Crohn's disease. The complex, multifactorial... (Review)
Review
Inflammatory bowel diseases (IBD) are chronic inflammatory gut disorders, majorly classified as ulcerative colitis and Crohn's disease. The complex, multifactorial etiopathogenesis of IBD involves genetic predisposition, environmental cues, aberrant mucosal immune response and a disturbed gut microbiota. Epidemiological trends, studies in gnotobiotic mice models and genome-wide association studies, identifying genes involved in microbial handling, together mount evidence in support of the gut microbiota playing a pivotal role in IBD pathogenesis. Both Crohn's disease and ulcerative colitis are characterized by severe dysbiosis of the gut microbiome, marked by an expansion of detrimental taxa and concomitant depletion of beneficial members. IBD is characterized by reduction in abundances of bacterial genera involved in production of short-chain fatty acids, bio-transformations of bile acids and synthesis of indole-based tryptophan compounds such as Faecalibacterium, Ruminococcus, Coprococcus, Dorea, Parabacteroides, Eubacterium, Oscillibacter and Prevotella and elevation in members of phyla Proteobacteria and Actinobacteria. This imbalance not only results in exaggerated immune signaling towards the microbial antigens, but also results in an altered metabolomic milieu that triggers additional inflammatory cascades. The present review provides insights into the bacterial dysbiosis observed across different intestinal sites and their metabolomic imprints participating in IBD.
Topics: Animals; Mice; Colitis, Ulcerative; Crohn Disease; Dysbiosis; Genome-Wide Association Study; Inflammatory Bowel Diseases; Bacteria
PubMed: 38374283
DOI: 10.1007/s12664-024-01541-1 -
Diabetes Dec 2023Prediabetes is a metabolic condition associated with gut microbiome composition, although mechanisms remain elusive. We searched for fecal metabolites, a readout of gut...
UNLABELLED
Prediabetes is a metabolic condition associated with gut microbiome composition, although mechanisms remain elusive. We searched for fecal metabolites, a readout of gut microbiome function, associated with impaired fasting glucose (IFG) in 142 individuals with IFG and 1,105 healthy individuals from the UK Adult Twin Registry (TwinsUK). We used the Cooperative Health Research in the Region of Augsburg (KORA) cohort (318 IFG individuals, 689 healthy individuals) to replicate our findings. We linearly combined eight IFG-positively associated metabolites (1-methylxantine, nicotinate, glucuronate, uridine, cholesterol, serine, caffeine, and protoporphyrin IX) into an IFG-metabolite score, which was significantly associated with higher odds ratios (ORs) for IFG (TwinsUK: OR 3.9 [95% CI 3.02-5.02], P < 0.0001, KORA: OR 1.3 [95% CI 1.16-1.52], P < 0.0001) and incident type 2 diabetes (T2D; TwinsUK: hazard ratio 4 [95% CI 1.97-8], P = 0.0002). Although these are host-produced metabolites, we found that the gut microbiome is strongly associated with their fecal levels (area under the curve >70%). Abundances of Faecalibacillus intestinalis, Dorea formicigenerans, Ruminococcus torques, and Dorea sp. AF24-7LB were positively associated with IFG, and such associations were partially mediated by 1-methylxanthine and nicotinate (variance accounted for mean 14.4% [SD 5.1], P < 0.05). Our results suggest that the gut microbiome is linked to prediabetes not only via the production of microbial metabolites but also by affecting intestinal absorption/excretion of host-produced metabolites and xenobiotics, which are correlated with the risk of IFG. Fecal metabolites enable modeling of another mechanism of gut microbiome effect on prediabetes and T2D onset.
ARTICLE HIGHLIGHTS
Prediabetes is a metabolic condition associated with gut microbiome composition, although mechanisms remain elusive. We investigated whether there is a fecal metabolite signature of impaired fasting glucose (IFG) and the possible underlying mechanisms of action. We identified a fecal metabolite signature of IFG associated with prevalent IFG in two independent cohorts and incident type 2 diabetes in a subanalysis. Although the signature consists of metabolites of nonmicrobial origin, it is strongly correlated with gut microbiome composition. Fecal metabolites enable modeling of another mechanism of gut microbiome effect on prediabetes by affecting intestinal absorption or excretion of host compounds and xenobiotics.
Topics: Adult; Humans; Prediabetic State; Diabetes Mellitus, Type 2; Niacin; Fasting; Glucose; Blood Glucose
PubMed: 37699401
DOI: 10.2337/db23-0170 -
The Journal of Nutrition Jan 2023Animal and small-cohort human studies have shown that tea consumption affects the gut microbiome, but evidence from large cohort studies is lacking.
BACKGROUND
Animal and small-cohort human studies have shown that tea consumption affects the gut microbiome, but evidence from large cohort studies is lacking.
OBJECTIVES
We examined associations between tea consumption and gut microbiome composition among older Chinese adults.
METHODS
The study included 1179 men and 1078 women from the Shanghai Men's and Women's Health Studies, who reported tea drinking status, type, amount, and duration at baseline and follow-up surveys (1996-2017) and were free of cancer, cardiovascular disease, and diabetes at stool collection (2015-2018). Fecal microbiome was profiled using 16S rRNA sequencing. Associations of tea variables with microbiome diversity and taxa abundance were evaluated using linear or negative binomial hurdle models after adjusting for sociodemographics, lifestyle, and hypertension status.
RESULTS
Mean age at stool collection was 67.2 ± 9.0 y in men and 69.6 ± 8.5 y in women. Tea drinking was not associated with microbiome ɑ-diversity in men or women; however, all tea variables were associated with β-diversity in men (P < 0.001). Significant associations with taxa abundance were also observed mostly in men. Current tea drinking, mainly green tea drinking, was associated with increase in orders Synergistales and RF39 in men (β = 0.30 to 0.42, all P ≤ 0.10) but not in women (P = 0.01). Also, increase in families Coriobacteriaceae, Odoribacteraceae, genera Collinsella, Odoribacter, and species Collinsella aerofaciens, Coprococcus catus, and Dorea formicigenerans were observed among men who drank >3.3 cups (781 mL)/d compared to that of nondrinkers (all P <0.10). The increased Coprococcus catus related to tea drinking was more evident among men without hypertension and inversely associated with the prevalence of hypertension (OR: 0.90; 95% CI: 0.84, 0.97; P = 0.03).
CONCLUSIONS
Tea consumption may affect gut microbiome β-diversity and abundance of some bacteria, which may contribute to reduced hypertension risk in Chinese men. Future studies should examine the sex-specific tea-gut microbiome associations and how certain bacteria may mediate the health benefits of tea.
Topics: Male; Humans; Adult; Female; Middle Aged; Aged; Gastrointestinal Microbiome; East Asian People; RNA, Ribosomal, 16S; Prospective Studies; China; Tea; Hypertension
PubMed: 36913464
DOI: 10.1016/j.tjnut.2022.12.002 -
Microorganisms Jul 2023A cross-sectional study involving 224 healthy Japanese adult females explored the relationship between ramen intake, gut microbiota diversity, and blood biochemistry....
A cross-sectional study involving 224 healthy Japanese adult females explored the relationship between ramen intake, gut microbiota diversity, and blood biochemistry. Using a stepwise regression model, ramen intake was inversely associated with gut microbiome alpha diversity after adjusting for related factors, including diets, Age, BMI, and stool habits (β = -0.018; r = -0.15 for Shannon index). The intake group of ramen was inversely associated with dietary nutrients and dietary fiber compared with the no-intake group of ramen. Sugar intake, as a short-chain fatty acid (SCFA)-producing gut microbiota, and γ-glutamyl transferase as a liver function marker were directly associated with ramen intake after adjustment for related factors including diets, gut microbiota, and blood chemistry using a stepwise logistic regression model, whereas is inconsistently less abundant in the ramen group. In conclusion, the increased ramen was associated with decreased gut bacterial diversity accompanying a perturbation of through the dietary nutrients, gut microbiota, and blood chemistry, while the methodological limitations existed in a cross-sectional study. People with frequent ramen eating habits need to take measures to consume various nutrients to maintain and improve their health, and dietary management can be applied to the dietary feature in ramen consumption.
PubMed: 37630452
DOI: 10.3390/microorganisms11081892 -
Oncoimmunology 2022The microbiome is now regarded as one of the hallmarks of cancer and several strategies to modify the gut microbiota to improve immune checkpoint inhibitor (ICI)...
The microbiome is now regarded as one of the hallmarks of cancer and several strategies to modify the gut microbiota to improve immune checkpoint inhibitor (ICI) activity are being evaluated in clinical trials. Preliminary data regarding the upper gastro-intestinal microbiota indicated that seropositivity was associated with a negative prognosis in patients amenable to ICI. In 97 patients with advanced melanoma treated with ICI, we assessed the impact of on outcomes and microbiome composition. We performed serology and profiled the fecal microbiome with metagenomics sequencing. Among the 97 patients, 22% were positive (Pos). Pos patients had a significantly shorter overall survival () compared to negative (Neg) patients. In addition, objective response rate and progression-free survival were decreased in Pos patients. Metagenomics sequencing did not reveal any difference in diversity indexes between the groups. At the taxa level, , and were increased in the Pos group, while and were over-represented in the Neg group. In a second independent cohort of patients with NSCLC, diversity indexes were similar in both groups and was increased in Neg patients. Our results demonstrated that the negative impact of on outcomes seem to be independent from the fecal microbiome composition. These findings warrant further validation and development of therapeutic strategies to eradicate in immuno-oncology arena.
Topics: Carcinoma, Non-Small-Cell Lung; Helicobacter Infections; Helicobacter pylori; Humans; Immune Checkpoint Inhibitors; Lung Neoplasms; Melanoma; Syndrome
PubMed: 35832043
DOI: 10.1080/2162402X.2022.2096535