Changes in oral microbiota after the initiation of chemotherapy in patients with hematopoietic tumors

Abstract Background Recently, the gut microbiota has been shown to play an important role in the response and resistance to chemotherapy. Although there is much knowledge about chemotherapy-induced changes in the gut microbiota, chemotherapy-associated changes in the oral microbiota remain unclear. Herein, we aimed to evaluate the changes in oral microbiota associated with the initiation of chemotherapy in patients with malignant hematopoietic tumors. Methods Oral samples were collected before and 8–20 days after the start of chemotherapy from 50 patients with malignant hematopoietic tumors who were starting chemotherapy for the first time. The 16S ribosomal RNA gene sequencing of bacterial DNA extracted from oral samples was performed to compare the oral microbiota before and after the initiation of chemotherapy. Results The richness or evenness of diversity in the ‘after start of chemotherapy’ group decreased significantly, compared with the ‘before start of chemotherapy’ group (alpha-diversity; observed operational taxonomic units (OTUs) index, p < 0.001; and Shannon’s index, p < 0.001). The overall salivary microbiota structure between the pre- and post-chemotherapy groups differed significantly (beta-diversity; unweighted UniFrac distances, p = 0.001; and weighted UniFrac distances, p = 0.003). Linear discriminant analysis effect size analysis demonstrated an increased abundance of species of certain genera, such as Staphylococcus, and decreased abundance of species of some genera, such as Streptococcus and Neisseria, in the ‘after-chemotherapy’ group, compared with those in the ‘before-chemotherapy’ group. The amounts and trends of change in the oral microbiota before and after the start of chemotherapy differed among the subjects. Of the 25 bacterial genera whose prevalence changed significantly before and after the start of chemotherapy, the proportion of oral commensals such as Streptococcus and Neisseria decreased in many subjects. In contrast, Staphylococcus and Pseudomonas were detected only in a few subjects, but their relative abundance increased significantly after the start of chemotherapy. Conclusions The oral microbiota of patients with hematopoietic tumors changed markedly after the initiation of chemotherapy. Our findings are expected to aid the elucidation of the pathogenesis of oral mucositis, which is an adverse event of chemotherapy, and the development of treatment methods for this condition.

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Effects of Helicobacter pylori Infection on the Oral Microbiota of Reflux Esophagitis Patients

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.732613 ◽

2021 ◽

Vol 11 ◽

Author(s):

Tian Liang ◽

Fang Liu ◽

Lijun Liu ◽

Zhiying Zhang ◽

Wenxue Dong ◽

...

Keyword(s):

Helicobacter Pylori ◽

Reflux Esophagitis ◽

Beta Diversity ◽

High Throughput Sequencing ◽

Alpha Diversity ◽

Vital Role ◽

Size Analysis ◽

Oral Microbiota ◽

Linear Discriminant ◽

Microbial Network

The human oral microbiota plays a vital role in maintaining metabolic homeostasis. To explore the relationship between Helicobacter pylori (Hp) and reflux esophagitis, we collected 86 saliva samples from reflux esophagitis patients (RE group) and 106 saliva samples from healthy people (C group) for a high-throughput sequencing comparison. No difference in alpha diversity was detected between the RE and the C groups, but beta diversity of the RE group was higher than the C group. Bacteroidetes was more abundant in the RE group, whereas Firmicutes was more abundant in the C group. The linear discriminant analysis effect size analysis demonstrated that the biomarkers of the RE group were Prevotella, Veillonella, Leptotrichia, and Actinomyces, and the biomarkers of the C group were Lautropia, Gemella, Rothia, and Streptococcus. The oral microbial network structure of the C group was more complex than that of the RE group. Second, to explore the effect of Hp on the oral microbiota of RE patients, we performed the 14C-urea breath test on 45 of the 86 RE patients. We compared the oral microbiota of 33 Hp-infected reflux esophagitis patients (REHpp group) and 12 non-Hp-infected reflux esophagitis patients (REHpn group). No difference in alpha diversity was observed between the REHpn and REHpp groups, and beta diversity of the REHpp group was significantly lower than that of the REHpn group. The biomarkers in the REHpp group were Veillonella, Haemophilus, Selenomonas, Megasphaera, Oribacterium, Butyrivibrio, and Campylobacter; and the biomarker in the REHpn group was Stomatobaculum. Megasphaera was positively correlated with Veillonella in the microbial network of the REHpp group. The main finding of this study is that RE disturbs the human oral microbiota, such as increased beta diversity. Hp infection may inhibit this disorderly trend.

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The Salivary Microbiome: Analysis of by Pyrosequencing and the Relationship with Helicobacter pylori Infection

10.1101/505115 ◽

2018 ◽

Cited By ~ 1

Author(s):

Yingjie Ji ◽

Xiao Liang ◽

Hong Lu

Keyword(s):

Helicobacter Pylori ◽

Oral Cavity ◽

Bacterial Diversity ◽

Alpha Diversity ◽

Oral Microbiota ◽

Operational Taxonomic Units ◽

Hypervariable Regions ◽

Salivary Microbiota ◽

Before And After ◽

H Pylori

Backgrounds: There have been reports of Helicobacter pylori (H. pylori) in the oral cavity and it has been suggested that the oral cavity may be a reservoir for H. pylori reflux from the stomach. Objectives: High-throughput pyrosequencing was used to assess the structure and composition of oral microbiota communities in individuals with or without confirmed H. pylori infection. Methods: Saliva samples were obtained from 34 H. pylori infected and 24 H. pylori uninfected subjects. Bacterial genomic DNA was extracted and examined by pyrosequencing by amplification of the 16S rDNA V3-V4 hypervariable regions followed by bioinformatics analysis. Saliva sampling was repeated from 22 of the 34 H. pylori infected subjects 2 months after H. pylori eradication. Results: High-quality sequences (2,812,659) clustered into 95,812 operational taxonomic units (OTUs; 97% identity), representing 440 independent species belonging to 138 genera, 68 families, 36 orders, 21 classes, and 11 phyla. Species richness (alpha diversity) of H. pylori infected subjects was similar to that of uninfected subjects. Eradication treatment decreased saliva bacterial diversity. Beta diversity analysis showed that the salivary microbial community structure differed between H. pylori infected and uninfected subjects both before and after H. pylori eradication. Conclusions: Salivary microbiota diversity was similar in H. pylori infected and uninfected individuals. Antibiotic therapy was associated with a decline in salivary bacterial diversity. Both H. pylori infection and its eradication caused the oral microbiota alterations in community and structure. The present of H. pylori in oral cavity was not related with its infection status in stomach.

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Modulation of Saliva Microbiota through Prebiotic Intervention in HIV-Infected Individuals

Nutrients ◽

10.3390/nu11061346 ◽

2019 ◽

Vol 11 (6) ◽

pp. 1346 ◽

Cited By ~ 1

Author(s):

Nuria Jiménez-Hernández ◽

Sergio Serrano-Villar ◽

Alba Domingo ◽

Xavier Pons ◽

Alejandro Artacho ◽

...

Keyword(s):

Hiv Infection ◽

Alpha Diversity ◽

Rrna Gene ◽

Oral Microbiota ◽

Microbiota Composition ◽

Hiv Status ◽

T Helper ◽

Immunodeficiency Virus ◽

Salivary Microbiota ◽

Rrna Gene Sequencing

Human immunodeficiency virus (HIV) infection is characterized by an early depletion of the mucosal associated T helper (CD4+) cells that impair the host immunity and impact the oral and gut microbiomes. Although, the HIV-associated gut microbiota was studied in depth, few works addressed the dysbiosis of oral microbiota in HIV infection and, to our knowledge, no studies on intervention with prebiotics were performed. We studied the effect of a six-week-long prebiotic administration on the salivary microbiota in HIV patients and healthy subjects. Also, the co-occurrence of saliva microorganisms in the fecal bacteria community was explored. We assessed salivary and feces microbiota composition using deep 16S ribosomal RNA (rRNA) gene sequencing with Illumina methodology. At baseline, the different groups shared the same most abundant genera, but the HIV status had an impact on the saliva microbiota composition and diversity parameters. After the intervention with prebiotics, we found a drastic decrease in alpha diversity parameters, as well as a change of beta diversity, without a clear directionality toward a healthy microbiota. Interestingly, we found a differential response to the prebiotics, depending on the initial microbiota. On the basis of 100% identity clustering, we detected saliva sequences in the feces datasets, suggesting a drag of microorganisms from the upper to the lower gastrointestinal tract.

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Pulmonary and intestinal microbiota dynamics during Gram-negative pneumonia-derived sepsis

Intensive Care Medicine Experimental ◽

10.1186/s40635-021-00398-4 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Nora S. Wolff ◽

Max C. Jacobs ◽

W. Joost Wiersinga ◽

Floor Hugenholtz

Keyword(s):

Gut Microbiota ◽

Pulmonary Inflammation ◽

Alpha Diversity ◽

Severe Pneumonia ◽

Fecal Microbiota ◽

Protective Role ◽

Oral Microbiota ◽

Post Inoculation ◽

Systemic Spread ◽

Pathogen Burden

Abstract Background The gut microbiome plays a protective role in the host defense against pneumonia. The composition of the lung microbiota has been shown to be predictive of clinical outcome in critically ill patients. However, the dynamics of the lung and gut microbiota composition over time during severe pneumonia remains ill defined. We used a mouse model of pneumonia-derived sepsis caused by Klebsiella pneumoniae in order to follow the pathogen burden as well as the composition of the lung, tongue and fecal microbiota from local infection towards systemic spread. Results Already at 6 h post-inoculation with K. pneumoniae, marked changes in the lung microbiota were seen. The alpha diversity of the lung microbiota did not change throughout the infection, whereas the beta diversity did. A shift between the prominent lung microbiota members of Streptococcus and Klebsiella was seen from 12 h onwards and was most pronounced at 18 h post-inoculation (PI) which was also reflected in the release of pro-inflammatory cytokines indicating severe pulmonary inflammation. Around 18 h PI, K. pneumoniae bacteremia was observed together with a systemic inflammatory response. The composition of the tongue microbiota was not affected during infection, even at 18–30 h PI when K. pneumoniae had become the dominant bacterium in the lung. Moreover, we observed differences in the gut microbiota during pulmonary infection. The gut microbiota contributed to the lung microbiota at 12 h PI, however, this decreased at a later stage of the infection. Conclusions At 18 h PI, K. pneumoniae was the dominant member in the lung microbiota. The lung microbiota profiles were significantly explained by the lung K. pneumoniae bacterial counts and Klebsiella and Streptococcus were correlating with the measured cytokine levels in the lung and/or blood. The oral microbiota in mice, however, was not influenced by the severity of murine pneumonia, whereas the gut microbiota was affected. This study is of significance for future studies investigating the role of the lung microbiota during pneumonia and sepsis.

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Association between changes in salivary microbiota with glucose levels during pregnancy – findings from a pilot study

10.21203/rs.3.rs-119072/v1 ◽

2020 ◽

Author(s):

Xin Zhang ◽

Pei Wang ◽

Liangkun Ma ◽

Rongjun Guo ◽

Yongjing Zhang ◽

...

Keyword(s):

Information Processing ◽

Pregnant Women ◽

Early Stage ◽

Fasting Blood Glucose ◽

Alpha Diversity ◽

Oral Microbiota ◽

Microbial Composition ◽

Health Maintenance ◽

Maternal Characteristics ◽

Salivary Microbiota

Abstract Background : Microbial shifts that correspond to host variations during pregnancy are vital in health maintenance. Significant changes have been reported in the oral microbiota of pregnant women when compared with nonpregnant women, but little is known about the dynamic shifts in oral microbiota during the pregnancy course. Methods : In this study, changes in salivary microbiota in 81 healthy pregnant women throughout the early stage (G1: 9-14 weeks), middle stage (G2: 21-28 weeks), and late stage (G3: 31-38 weeks) were investigated with 16S rRNA sequencing techniques. Correlations between salivary microbiota and maternal characteristics, including fasting blood glucose (FBG) levels, were evaluated. Results : Alpha diversity indexes were stable throughout pregnancy, but significant changes were found in beta diversity measured by weighted and unweighted UniFrac distances. Fourteen dominant trimester-specific taxa were identified using the LEfSe method, including Bacteroidetes in G1, Proteobacteria in G2 and Firmicutes in G3 at the phylum level. Tax4Fun prediction analysis revealed significant changes in Genetic Information Processing, Environmental Information Processing, Unclassified and Human Diseases in G2 and in Metabolism in G3 when compared to G1. Significant correlations were found between FBG levels and microbial composition, and these correlations were independent of gestational diabetes mellitus (GDM) status. Conclusion : Within the limitations of this study, the dynamic changes in salivary microbiota during pregnancy were characterized, and beyond pregnancy, FBG was also involved in shaping the salivary microbiota.

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Dietary Correlates of Oral and Gut Microbiota in the Water Monitor Lizard, Varanus salvator (Laurenti, 1768)

Frontiers in Microbiology ◽

10.3389/fmicb.2021.771527 ◽

2022 ◽

Vol 12 ◽

Author(s):

Yu Du ◽

Jun-Qiong Chen ◽

Qian Liu ◽

Jian-Chao Fu ◽

Chi-Xian Lin ◽

...

Keyword(s):

Gut Microbiota ◽

Water Environment ◽

Alpha Diversity ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Oral Microbiota ◽

Monitor Lizard ◽

Varanus Salvator ◽

In The Wild ◽

Monitor Lizards

Numerous studies have demonstrated that food shapes the structure and composition of the host’s oral and gut microbiota. The disorder of oral and gut microbiota may trigger various host diseases. Here, we collected oral and gut samples from wild water monitor lizards (Varanus salvator) and their captive conspecifics fed with bullfrogs, eggs, and depilated chicken, aiming to examine dietary correlates of oral and gut microbiota. We used the 16S rRNA gene sequencing technology to analyze the composition of the microbiota. Proteobacteria and Bacteroidota were the dominant phyla in the oral microbiota, and so were in the gut microbiota. The alpha diversity of microbiota was significantly higher in the gut than in the oral cavity, and the alpha diversity of oral microbiota was higher in captive lizards than in wild conspecifics. Comparing the relative abundance of oral and gut bacteria and their gene functions, differences among different animal groups presumably resulted from human contact in artificial breeding environments and complex food processing. Differences in gene function might be related to the absolute number and/or the taxonomic abundance of oral and gut microorganisms in the wild and the water environment. This study provides not only basic information about the oral and gut microbiota of captive and wild water monitor lizards, but also an inference that feeding on frogs and aquatic products and reducing human exposure help water monitor lizards maintain a microbiota similar to that in the wild environment.

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The gut mycobiota of rural and urban individuals is shaped by geography

10.21203/rs.3.rs-19519/v2 ◽

2020 ◽

Author(s):

Mubanga Kabwe ◽

Surendra Vikram ◽

Khodani Mulaudzi ◽

Janet Jansson ◽

Thulani Makhalyane

Keyword(s):

Gut Microbiota ◽

South African ◽

Geographic Location ◽

Size Analysis ◽

Human Gut ◽

Linear Discriminant ◽

Knowledge Deficit ◽

Rural And Urban ◽

Its Gene ◽

Species Specific

Abstract Background Understanding the structure and drivers of gut microbiota remains a major ecological endeavour. Recent studies have shown that several factors including diet, lifestyle and geography may substantially shape the human gut microbiota. However, most of these studies have focused on the more abundant bacterial component and comparatively less is known regarding fungi in the human gut. This knowledge deficit is especially true for rural and urban African populations. Therefore, we assessed the structure and drivers of rural and urban gut mycobiota. Results Our participants (n=100) were balanced by geography and sex. The mycobiota of these geographically separated cohorts was characterized using amplicon analysis of the Internal Transcribed Spacer (ITS) gene. We further assessed biomarker species specific to rural and urban cohorts. In addition to phyla which have been shown to be ubiquitous constituents of gut microbiota, Pichia were key constituents of the mycobiota. We found that geographic location was a major driver of gut mycobiota. Other factors such as smoking where also determined gut mycobiota albeit to a lower extent, as explained by the small proportion of total variation. Linear discriminant and the linear discriminant analysis effect size analysis revealed several distinct urban and rural biomarkers. Conclusions Together, our analysis reveals distinct community structure in urban and rural South African individuals. Geography was shown to be a key driver of rural and urban gut mycobiota.

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The gut microbiota of rural and urban individuals is shaped by geography and lifestyle

10.21203/rs.3.rs-19519/v1 ◽

2020 ◽

Author(s):

Mubanga Kabwe ◽

Surendra Vikram ◽

Khodani Mulaudzi ◽

Janet Jansson ◽

Thulani Makhalyane

Keyword(s):

Gut Microbiota ◽

Smoking Status ◽

Geographic Location ◽

Size Analysis ◽

Human Gut ◽

Related Factors ◽

Linear Discriminant ◽

Knowledge Deficit ◽

Rural And Urban ◽

Species Specific

Abstract Background Understanding the structure and drivers of gut microbiota remains a major ecological endeavour. Recent studies have shown that several factors including diet, lifestyle and geography may substantially shape the human gut microbiota. However, most of these studies have focused on the more abundant bacterial component and comparatively less is known regarding fungi in the human gut. This knowledge deficit is especially true for rural and urban African populations. Therefore, we assessed the structure and drivers of rural and urban gut mycobiota. Results Our participants (n=100) were balanced by geography and sex. The mycobiota of these geographically separated cohorts was characterized using amplicon analysis of the Internal Transcribed Spacer (ITS) gene. We further assessed biomarker species specific to rural and urban cohorts. In addition to phyla which have been shown to be ubiquitous constituents of gut microbiota, Pichia were key constituents of the mycobiota. We found that several factors including geographic location and lifestyle factors such as the smoking status were major drivers of gut mycobiota. Linear discriminant and the linear discriminant analysis effect size analysis revealed several distinct urban and rural biomarkers. Conclusions Together, our analysis reveals distinct community structure in urban and rural South African individuals. Geography and lifestyle related factors were shown to be key drivers of rural and urban gut microbiota.

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The gut microbiota of rural and urban individuals is shaped by geography and lifestyle

10.1101/2020.03.19.999656 ◽

2020 ◽

Author(s):

Mubanga Hellen Kabwe ◽

Surendra Vikram ◽

Khodani Mulaudzi ◽

Janet K. Jansson ◽

Thulani P. Makhalanyane

Keyword(s):

Gut Microbiota ◽

Smoking Status ◽

Geographic Location ◽

Lifestyle Factors ◽

Size Analysis ◽

Human Gut ◽

Related Factors ◽

Linear Discriminant ◽

Rural And Urban ◽

Species Specific

AbstractUnderstanding the structure and drivers of gut microbiota remains a major ecological endeavour. Recent studies have shown that several factors including diet, lifestyle and geography may substantially shape the human gut microbiota. However, most of these studies have focused on the more abundant bacterial component and comparatively less is known regarding fungi in the human gut. This knowledge deficit is especially true for rural and urban African populations. Therefore, we assessed the structure and drivers of rural and urban gut mycobiota. Our participants (n=100) were balanced by geography and sex. The mycobiota of these geographically separated cohorts was characterized using amplicon analysis of the Internal Transcribed Spacer (ITS) gene. We further assessed biomarker species specific to rural and urban cohorts. In addition to phyla which have been shown to be ubiquitous constituents of gut microbiota, Pichia were key constituents of the mycobiota. We found that several factors including geographic location and lifestyle factors such as the smoking status were major drivers of gut mycobiota. Linear discriminant and the linear discriminant analysis effect size analysis revealed several distinct urban and rural biomarkers. Together, our analysis reveals distinct community structure in urban and rural South African individuals. Geography and lifestyle related factors were shown to be key drivers of rural and urban gut microbiota.ImportanceThe past decade has revealed substantial insights regarding the ecological patterns of gut microbiomes. These studies have shown clear differences between the microbiomes of individuals living in urban and rural locations. Yet, in contrast to bacteria we know substantially less regarding the fungal gut microbiota (mycobiome). Here we provide the first insights regarding the mycobiome of individuals from urban and rural locations. We show that these communities are geographically structured. Further we show that lifestyle factors, such as diet and smoking, are strong drivers explaining community variability.

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Ramadan Fasting Leads to Shifts in Human Gut Microbiota Structured by Dietary Composition

Frontiers in Microbiology ◽

10.3389/fmicb.2021.642999 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ikram Ali ◽

Ke Liu ◽

Danfeng Long ◽

Shah Faisal ◽

Mian Gul Hilal ◽

...

Keyword(s):

Gut Microbiota ◽

Ethnic Groups ◽

Alpha Diversity ◽

Rrna Gene ◽

Dietary Composition ◽

Human Gut ◽

Ramadan Fasting ◽

Human Gut Microbiota ◽

Before And After ◽

Chinese Group

The structure and diversity of human gut microbiota are directly related to diet, though less is known about the influences of ethnicity and diet-related behaviors, such as fasting (intermittent caloric restriction). In this study, we investigated whether fasting for Ramadan altered the microbiota in Chinese and Pakistani individuals. Using high-throughput 16S rRNA gene sequencing and self-reported dietary intake surveys, we determined that both the microbiota and dietary composition were significantly different with little overlap between ethnic groups. Principal Coordinate Analyses (PCoA) comparison of samples collected from both groups before and after fasting showed partial separation of microbiota related to fasting in the Pakistani group, but not in the Chinese group. Measurement of alpha diversity showed that Ramadan fasting significantly altered the coverage and ACE indices among Chinese subjects, but otherwise incurred no changes among either group. Specifically, Prevotella and Faecalibacterium drove predominance of Bacteroidetes and Firmicutes in the Pakistani group, while Bacteroides (phylum Bacteroidetes) were the most prevalent among Chinese participants both before and after fasting. We observed significant enrichment of some specific taxa and depletion of others in individuals of both populations, suggesting that fasting could affect beta diversity. Notably, Dorea, Klebsiella, and Faecalibacterium were more abundant in the Chinese group after fasting, while Sutterella, Parabacteroides, and Alistipes were significantly enriched after fasting in the Pakistani group. Evaluation of the combined groups showed that genera Coprococcus, Clostridium_XlV, and Lachnospiracea were all significantly decreased after fasting. Analysis of food intake and macronutrient energy sources showed that fat-derived energy was positively associated with Oscillibacter and Prevotella, but negatively associated with Bacteroides. In addition, the consumption of sweets was significantly positively correlated with the prevalence of Akkermansia. Our study indicated that diet was the most significant influence on microbiota, and correlated with ethnic groups, while fasting led to enrichment of specific bacterial taxa in some individuals. Given the dearth of understanding about the impacts of fasting on microbiota, our results provide valuable inroads for future study aimed at novel, personalized, behavior-based treatments targeting specific gut microbes for prevention or treatment of digestive disorders.

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