Effects of Proton Pump Inhibitors on the Gastrointestinal Microbiota in Gastroesophageal Reflux Disease

Unlocking the secrets of the human gut microbiota: Comprehensive review on its role in different diseases

The human gut microbiota, a complex and diverse community of microorganisms, plays a crucial role in maintaining overall health by influencing various physiological processes, including digestion, immune function, and disease susceptibility. The balance between beneficial and harmful bacteria is essential for health, with dysbiosis - disruption of this balance - linked to numerous conditions such as metabolic disorders, autoimmune diseases, and cancers. This review highlights key genera such as Enterococcus, Ruminococcus, Bacteroides, Bifidobacterium, Escherichia coli, Akkermansia muciniphila, Firmicutes (including Clostridium and Lactobacillus), and Roseburia due to their well-established roles in immune regulation and metabolic processes, but other bacteria, including Clostridioides difficile, Salmonella, Helicobacter pylori, and Fusobacterium nucleatum, are also implicated in dysbiosis and various diseases. Pathogenic bacteria, including Escherichia coli and Bacteroides fragilis, contribute to inflammation and cancer progression by disrupting immune responses and damaging tissues. The potential for microbiota-based therapies, such as probiotics, prebiotics, fecal microbiota transplantation, and dietary interventions, to improve health outcomes is examined. Future research directions in the integration of multi-omics, the impact of diet and lifestyle on microbiota composition, and advancing microbiota engineering techniques are also discussed. Understanding the gut microbiota's role in health and disease is essential for formulating personalized, efficacious treatments and preventive strategies, thereby enhancing health outcomes and progressing microbiome research.

Correlation Between Gastroesophageal Reflux Disease and Small Intestinal Bacterial Overgrowth: Analysis of Intestinal Microbiome and Metabolic Characteristics

Background

Our study examines the relationship between gastroesophageal reflux disease (GERD) and small intestinal bacterial overgrowth (SIBO), focusing on the potential impact of acid-suppressive drugs. We also explore changes in gut microbiota and metabolism in patients with both conditions.

Methods

This study included patients from the Department of Gastroenterology, Beijing Shijitan Hospital, between February 2021 and November 2023. All patients underwent assessments including questionnaires, hydrogen and methane breath tests, and gastroscopy. GERD was diagnosed using the GERD-Q scale and gastroscopy, while SIBO was diagnosed via breath tests. We analyzed the correlation between GERD and SIBO, identified risk factors for SIBO, and examined the gut microbiota using 16S rRNA sequencing to explore the relationship between GERD and SIBO.

Results

The retrospective study included 394 patients.148 with GERD and 287 with positive SIBO results. Among these, 270 had a positive methane (CH4) breath test and 97 had a positive hydrogen (H2) breath test. GERD was more common in patients with positive SIBO (P = 0.007), and the link between CH4 breath tests and GERD was stronger than that with H2 breath tests (P = 0.020). Logistic regression showed GERD is an independent risk factor for SIBO. Short-term, low-dose acid-suppressive drugs did not affect SIBO development. 16S rRNA sequencing of fecal microbiota from 24 patients showed dominant microbiota in SIBO-positive GERD patients included bacteroides uniformis and bacteroides stercoris. Patients with both GERD and SIBO had differential metabolites, mainly associated with ATP-Binding Cassette transporters (ABC transporters).

Conclusion

GERD is strongly linked to SIBO, especially in patients with a positive CH4 breath test. The gut microbiota in GERD and SIBO patients differs from healthy individuals, with bacteroides uniformis as a key marker. Metabolic changes are mainly related to ABC transporter metabolites.

Emerging Long-Term Risks of the Use of Proton Pump Inhibitors and Potassium-Competitive Acid Blockers

Acid-related disorders represent a significant global health burden. Pharmacological treatment of these conditions has at times been challenged and limited by incomplete effectiveness, antibiotic resistance, adverse medication effects and/or interactions, and disease recurrence. Since the early 1990s, the mainstay of treatment has been proton pump inhibitors (PPIs). Recently, the US Food and Drug Administration issued a clearance for vonoprazan, a potassium-competitive acid blocker (PCAB). PCABs are a new class of acid-suppressing agents that may overcome some of these challenges. The aim of this review is to evaluate and compare the emerging long-term risks of PPI and PCAB therapies.

Impact of short-term proton pump inhibitors vs. histamine-2 receptor antagonists on gut microbiota in patients with acute coronary syndrome: A multicenter randomized trial

BACKGROUND

Several randomized controlled studies have suggested that the prophylactic use of proton pump inhibitors (PPIs) in intensive care unit (ICU) patients could not reduce the incidence of gastrointestinal bleeding (GIB) and may increase adverse events such as intestinal infection and pneumonia. Gut microbiota may play a critical role in the process. PPIs has been widely prescribed for GIB prophylaxis in patients with acute coronary syndrome (ACS). This study aimed to determine the short-term effects of PPI and histamine-2 receptor antagonist (H2RA) treatment on gut microbiota of ACS patients.

METHODS

The study was designed as a single-blind, multicenter, three-parallel-arm, randomized controlled trial conducted at three centers in Beijing, China. We enrolled ACS patients at low-to-medium risk of GIB and randomized (2:2:1) them to either PPI (n = 40), H2RA (n = 31), or control group (n = 21). The primary outcomes were the alterations in gut microbiota after 7 days of acid suppressant therapy. Stool samples were collected at baseline and 7 days and analyzed by 16S rRNA gene sequencing.

RESULTS

There were no significant changes in the diversity of gut microbiota after the short-term use of acid suppressants, but the abundance of Fusobacterium significantly increased and that of Bifidobacterium significantly decreased, especially in PPI users. In addition, the abundance of some pathogenic bacteria, including Enterococcus and Desulfovibrio, was significantly elevated in the PPI users. The fecal microbiota of the PPI users included more arachidonic acid metabolism than that of control group.

CONCLUSIONS

PPIs may increase the risk of infection by adversely altering gut microbiota and elevating arachidonic acid metabolism, which may produce multiple proinflammatory mediators. For ACS patients at low-to-medium risk of GIB, sufficient caution should be paid when acid-suppressant drugs are prescribed, especially PPIs.

REGISTRATION

www.chictr.org.cn/ (ChiCTR2000029552).

Longitudinal Microbiome Changes in Children Exposed to Proton Pump Inhibitors

INTRODUCTION

Proton pump inhibitor (PPI) use has been associated with an increased risk of gastrointestinal and upper respiratory infections in children. There are limited longitudinal data on the effect of PPI in children. The goal of this prospective observational study was to compare the stool and oropharyngeal microbiome of children before and after starting PPIs.

METHODS

We prospectively recruited participants from a gastroenterology clinic. Consented participants provided stool samples and oropharyngeal swabs at baseline and after 8 weeks of PPI therapy. Microbiome changes were measured by analyzing 16S sequencing from both body sites at both time points.

RESULTS

Thirty-four participants completed the study and provided samples both at baseline and after 8 weeks on PPI therapy. Of those, 24 participants had sufficient sequencing from both stool and oropharyngeal samples at both time points. There were no differences between the pre-PPI and post-PPI samples using beta-diversity metrics in either the oropharynx or stool. There were, however, significant changes in specific taxa. There was an enrichment of Streptococcus in the stool after PPI use and a reduction in the relative abundance of Bifidobacterium , Peptostreptococcus , and Turicibacter ( P -values < 0.01). Furthermore, there was an increase in the relative abundance of oropharyngeal bacteria in the stool after PPI therapy. This enrichment of oropharyngeal bacteria in the stool was most prominent in younger participants.

DISCUSSION

Further investigation is needed to determine the clinical and microbial factors that predispose or protect against microbiome changes due to PPI use and why young children are more susceptible to this PPI effect.

Gastroesophageal Reflux Disease and Preterm Birth: Univariate and Multivariate Mendelian Randomization

Background

Observational studies have established a connection between Gastroesophageal reflux disease (GERD) and preterm birth (PTB). Nevertheless, these correlations can be affected by residual confounding or reverse causality, resulting in ambiguity regarding the connection. The objective of this study was to assess the relationship between genetically predicted GERD and PTB.

Methods

Initially, we performed bidirectional univariate Mendelian randomization (UVMR) analysis utilizing publicly accessible genome-wide association studies (GWAS) data. The primary analytical approach employed to determine the causal impact between GERD and PTB is the inverse variance weighted technique (IVW). Subsequently, we utilized multivariate Mendelian randomization (MVMR) to adjust for potential factors that could influence the results, such as body mass index (BMI), maternal smoking around birth, educational attainment, household income, and Townsend deprivation index (TDI). Furthermore, we performed a sequence of comprehensive sensitivity analyses to assess the reliability of our MR findings.

Results

The UVMR analysis results showed a significant correlation between GERD and PTB (odds ratio [OR]: 1.810; 95% confidence interval [CI]: 1.344-2.439; P=9.60E-05) in the IVW model, and the Weighted median method (OR=1.591, 95% CI=1.094-2.315, P=0.015) revealed consistent results. The inverse MR findings suggest no causal link between PTB and the incidence of GERD. In addition, the sensitivity analysis did not detect heterogeneity or horizontal pleiotropy, and the "leave-one-out" examination confirmed that the causal estimation is unlikely to be influenced by the single nucleotide polymorphisms (SNPs) effect. The MVMR analysis demonstrated that the causal association between GERD and PTB still existed after considering BMI, maternal smoking around birth, educational attainment, household income, and TDI (OR=1.921, 95% CI=1.401-2.634, P=5.08E-05).

Conclusion

This study presents evidence indicating that genetically predicted GERD can heighten the risk of PTB. Therefore, it is advisable to perform focused screening for pregnant women with GERD in order to find the initial signs of PTB and promptly apply intervention strategies to extend the duration of pregnancy.

Spatial Variation of the Gastrointestinal Microbiota in Response to Long-Term Administration of Vonoprazan in Mice With High Risk of Gastric Cancer

BACKGROUND

Vonoprazan, a potassium-competitive acid blocker, is superior to traditional proton pump inhibitor (PPI) in acid suppression and has been approved in the treatment of acid-related disorders. Accumulating evidence suggest associations between PPI use and gut microbiota, yet the effect of vonoprazan on GI microbiota is obscure.

METHODS

Transgenic FVB/N insulin-gastrin (INS-GAS) mice as a model of gastric cancer (GC) were administered vonoprazan by gavage every other day for 12 weeks. Stomachs were evaluated by histopathology, Ki-67 proliferation index, and inflammatory cytokines. The mucosal and lumen microbiota from stomach, jejunum, ileum, cecum, and feces were detected using 16S rRNA gene sequencing.

RESULTS

Higher incidence of intestinal metaplasia and epithelial proliferation were observed in the vonoprazan group than that in the control mice. Vonoprazan also elevated the gastric expression of proinflammatory cytokines, including TNF-α, IL-1β, and IL-6. Each mice comprised a unique microbiota composition that was consistent across different niches. The structure of GI microbiota changed dramatically after vonoprazan treatment with the stomach being the most disturbed segment. Vonoprazan administration shifted the gut microbiota toward the enrichment of pathogenic Streptococcus, Staphylococcus, Bilophila, and the loss of commensal Prevotella, Bifidobacterium, and Faecalibacterium. Interestingly, compared to the controls, microbial interactions were weaker in the stomach while stronger in the jejunum of the vonoprazan group.

CONCLUSIONS

Long-term vonoprazan treatment promoted gastric lesions in male INS-GAS mice, with the disequilibrium of GI microbiome. The clinical application of vonoprazan needs to be judicious particularly among those with high risk of GC.

The Lactulose Breath Test Can Predict Refractory Gastroesophageal Reflux Disease by Measuring Bacterial Overgrowth in the Small Intestine

OBJECTIVE

The diagnosis of RGERD in patients typically involves 24-hour esophageal pH monitoring, but due to its invasiveness and low patient compliance, new screening methods are needed. In this study, a lactulose breath test (LBT) was conducted to detect the growth of small intestine bacteria (SIBO) and explore the potential relationship between LBT and RGERD to identify a new treatment method for RGERD.

METHODS

A total of 178 patients with gastroesophageal reflux were enrolled from June 2020 to December 2022 in the Gastroenterology Department, Building 3, the First Affiliated Hospital of Kunming Medical University; these patients included 96 patients with nonrefractory GERD (NRGERD) and 82 patients with RGERD. The Gerd Q score, reflux symptom index (RSI) score, gastroscopy results, clinical symptoms, and other related indicators were collected. Statistical methods were used to analyze the gathered data.

RESULTS

The incidence of acid reflux and heartburn in patients with RGERD was significantly greater than that in patients with NRGERD (67.10% vs. 42.70%, P<0.01 and 65.00% vs. 34.40%, P<0.01). The CH4 values of patients with RGERD were significantly greater than those of patients with NRGERD at each time point, and there was a correlation between the CH4 values at 60 min and RGERD (P<0.05). For patients with RGERD, the incidence of abdominal pain, acid regurgitation, and heartburn was greater in the CH4-positive group than in the CH4-negative group (61.90% vs. 57.50%, 69.05% vs. 65.00%, 69.05% vs. 57.50%, P>0.05). The incidence of nausea was also greater in the CH4-positive group than in the CH4-negative group (61.90% vs. 35.00%, P<0.05).

CONCLUSION

Increased CH4 levels are correlated with RGERD. In addition, patients with RGERD may develop SIBO after long-term use of PPIs, and interventions involving SIBO could provide new ideas for the treatment of RGERD.

Gastroesophageal reflux disease and non-alcoholic fatty liver disease: a two-sample Mendelian randomization combined with meta-analysis

Accumulating evidence from observational studies have suggested an association between gastroesophageal reflux disease (GERD) and non-alcoholic fatty liver disease (NAFLD). However, due to that such studies are prone to biases, we imported Mendelian randomization (MR) to explore whether the causal association between two diseases exsit. Hence, we aimed to analysis the potential association with MR. The single nucleotide polymorphisms (SNPs) of GERD were retrieved from the genome-wide association study dataset as the exposure. The SNPs of NAFLD were taken from the FinnGen dataset as the outcome. The relationship was analyzed with the assistance of inverse variance weighted, MR-Egger, and weighted median. We also uitilized the MR-Egger intercept, Cochran's Q test, leave-one-out analysis, MR-PRESSO, and Steiger directionality test to evaluate the robustness of the causal association. The meta-analysis were also implemented to give an overall evaluation. Finally, our analysis showed a causal relationship between GERD and NAFLD with aid of MR and meta-analysis (OR 1.71 95% CI 1.40-2.09; P < 0.0001).

Characterization of tongue coating microbiome from patients with colorectal cancer

Background

Tongue coating microbiota has aroused particular interest in profiling oral and digestive system cancers. However, little is known on the relationship between tongue coating microbiome and colorectal cancer (CRC).

Methods

Metagenomic shotgun sequencing was performed on tongue coating samples collected from 30 patients with CRC, 30 patients with colorectal polyps (CP), and 30 healthy controls (HC). We further validated the potential of the tongue coating microbiota to predict the CRC by a random forest model.

Results

We found a greater species diversity in CRC samples, and the nucleoside and nucleotide biosynthesis pathway was more apparent in the CRC group. Importantly, various species across participants jointly shaped three distinguishable fur types.The tongue coating microbiome profiling data gave an area under the receiver operating characteristic curve (AUC) of 0.915 in discriminating CRC patients from control participants; species such as Atopobium rimae, Streptococcus sanguinis, and Prevotella oris aided differentiation of CRC patients from healthy participants.

Conclusion

These results elucidate the use of tongue coating microbiome in CRC patients firstly, and the fur-types observed contribute to a better understanding of the microbial community in human. Furthermore, the tongue coating microbiota-based biomarkers provide a valuable reference for CRC prediction and diagnosis.

A rapid-floating natural polysaccharide gel-raft with double-effect for the treatment of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a prevalent gastrointestinal condition characterized by regurgitating stomach contents into the esophagus, causing mucosal damage or erosion. Clinical physical protection treatment mainly relies on the use of floating rafts. Bletilla striata (BS) is widely regarded as the first-choice drug for treating digestive tract injuries in Chinese Medicine. The rapid-floating gel-raft (B-R) was prepared via a one-step swelling method using natural BS polysaccharide and glyceryl monooleate. Panax notoginseng saponins (PNS) were loaded to further prepare P/B-R according to clinical experience. Possessing hydrophobic dense, stratified porous structure and stable rheological properties, an outperforming floating performance of P/B-R was proven compared with Gaviscon® (alginate-antacid formulation) in vitro. In vivo imaging results showed that P/B-R can retain and adhere to the gastric mucosa of rats for up to 90 min, protecting and repairing the mucosa. Besides physical protection in situ, the systemic effects of antioxidant and anti-inflammatory actions for treating GERD were achieved through the intestinal release of PNS. Acid-labile PNS was protected by P/B-R against gastric acid, attaining the desired release and permeability. A significantly effective mucosa injury protective effect of P/B-R was found in ethanol-induced gastric damage model on rats. Moreover, P/B-R exhibits excellent biosafety at the cellular level.

Causal relationship between gut microbiota and risk of gastroesophageal reflux disease: a genetic correlation and bidirectional Mendelian randomization study

Background

Numerous observational studies have identified a linkage between the gut microbiota and gastroesophageal reflux disease (GERD). However, a clear causative association between the gut microbiota and GERD has yet to be definitively ascertained, given the presence of confounding variables.

Methods

The genome-wide association study (GWAS) pertaining to the microbiome, conducted by the MiBioGen consortium and comprising 18,340 samples from 24 population-based cohorts, served as the exposure dataset. Summary-level data for GERD were obtained from a recent publicly available genome-wide association involving 78 707 GERD cases and 288 734 controls of European descent. The inverse variance-weighted (IVW) method was performed as a primary analysis, the other four methods were used as supporting analyses. Furthermore, sensitivity analyses encompassing Cochran's Q statistics, MR-Egger intercept, MR-PRESSO global test, and leave-one-out methodology were carried out to identify potential heterogeneity and horizontal pleiotropy. Ultimately, a reverse MR assessment was conducted to investigate the potential for reverse causation.

Results

The IVW method's findings suggested protective roles against GERD for the Family Clostridiales Vadin BB60 group (P = 0.027), Genus Lachnospiraceae UCG004 (P = 0.026), Genus Methanobrevibacter (P = 0.026), and Phylum Actinobacteria (P = 0.019). In contrast, Class Mollicutes (P = 0.037), Genus Anaerostipes (P = 0.049), and Phylum Tenericutes (P = 0.024) emerged as potential GERD risk factors. In assessing reverse causation with GERD as the exposure and gut microbiota as the outcome, the findings indicate that GERD leads to dysbiosis in 13 distinct gut microbiota classes. The MR results' reliability was confirmed by thorough assessments of heterogeneity and pleiotropy.

Conclusions

For the first time, the MR analysis indicates a genetic link between gut microbiota abundance changes and GERD risk. This not only substantiates the potential of intestinal microecological therapy for GERD, but also establishes a basis for advanced research into the role of intestinal microbiota in the etiology of GERD.

Association and Mechanisms of Proton Pump Inhibitors Use with Type-2Diabetes Mellitus Incidence in Adults: A Systemic Review andMeta-Analysis

BACKGROUND

Proton pump inhibitors (PPIs) are an extensively prescribed class of anti-ulcer drugs. This systematic review aimed to investigate the association between PPI use and the risk of new-onset diabetes mellitus or type 2 diabetes (T2DM) incidence.

METHODS

A comprehensive literature search was conducted in PubMed, Scopus, Cochrane Library, and ClinicalTrials.gov using the search terms "proton pump inhibitor," "proton pump inhibitors," "PPIs," "diabetes mellitus," and "type 2 diabetes" from inception to February 2023. Statistical analyses were performed using the "Review Manager 5.4" version, and a statistically highly significant P-value <0.05 was set.

RESULTS

This systematic review identified 12 studies (8 cohort, 1 RCT, and 3 case-control) with a total of 12, 64, 816 population, and the median age ranged from ≥18 yrs to ≤ 75 yrs. The pooled relative risk (RR) observations of a random-effects meta-analysis model showed that chronic exposure to PPI use has a significant association with T2DM risk incidence (RR, 2.44; 95% confidence interval, 1.31-4.54; I2 = 99%, P < 0.00001). The systematic review findings of the three case-control studies also supported an association of dose-dependent and chronic use of PPIs with an incidence of T2DM among chronic users.

CONCLUSION

The systematic review concludes that chronic PPI exposure increases the risk of T2DM incidence. The authors recommend the shortest possible duration of PPI use and not prescribing PPIs to high-risk prediabetics and those without a compelling indication for PPI use. Regular education to patients regarding adverse reactions with prolonged use may decrease the risk of adverse effects associated with PPIs. The authors suggest that gut dysbiosis, hypergastrinemia, hypomagnesemia, decreased pancreatic secretions and IGF-1 levels, and PXR activation associated with chronic acid suppression among chronic PPI users and the potency of PPIs might explain the association between abnormal glucose metabolism and T2DM incidence. Finally, the authors recommend further randomized controlled trials to investigate the association between PPIs and the risk of new-onset T2DM incidence.

The impact of proton pump inhibitors on the course of ulcerative colitis: a cohort study of over 10,000 newly diagnosed patients in Norway

BACKGROUND AND AIMS

Proton pump inhibitors (PPI) affect the gastrointestinal microbiota, which is thought to play a role in the pathogenesis of ulcerative colitis (UC). Previous studies suggest an association between PPI use and risk of incident UC as well as disease course. The aim of the study was to examine if PPI exposure is associated with disease course in UC patients.

METHODS

A national cohort consisting of all newly diagnosed UC patients from 2010 to 2020 was defined combining data from Norwegian registries. PPI exposure was included as a time dependent variable with a 30 day time lag from starting the drug. Outcomes were starting advanced therapies including anti-TNF, systemic glucocorticoids, any additional systemic anti-inflammatory medication and undergoing colectomy during follow-up. Time-dependent Cox regressions included the variables PPI use, first systemic glucocorticoid prescription, first UC hospitalization, age-groups and sex.

RESULTS

The study cohort consisted of 10,149 patients with median age 40 years (IQR 27-56) and 56% males. PPI use independently increased the risk of starting advanced therapies (HR 1.54, 95% CI 1.36-1.73, p < 0.005), starting systemic glucocorticoids (HR 1.20, 95% CI 1.07-1.34, p < 0.005), starting any additional anti-inflammatory treatment (HR 1.18, 95%CI 1.05-1.32, p < 0.01) and undergoing colectomy (HR 1.52, 95%CI 1.17-1.98, p < 0.005).

CONCLUSIONS

PPI use was associated with unfavorable outcomes including advanced therapy initiation, additional anti-inflammatory medications and undergoing colectomy. Although further studies are needed, the evidence suggests that PPIs could affect the course of UC and should be used cautiously in UC patients.

Development and evaluation of anti-reflux functional-oral suspension raft composed of sodium alginate-mung bean protein complex

This study aimed to develop a sodium alginate (Na alginate) and mung bean protein (MBP) raft complex to improve gastric reflux symptoms. Na alginate and MBP complexes with different ratios (1:1, 2:1, and 3:1, respectively) were used for raft formulations through a wet Maillard reaction. Structural properties of raft strength, reflux resistance, intrinsic fluorescence emission spectroscopy, and Fourier transform infrared spectroscopy (FTIR) were investigated for rafts. The suspension 1:1 Na alginate/MBP with 0 h Maillard reaction time exhibited the lowest sedimentation volume among the suspensions. In contrast, 3:1 Na alginate/MBP with 6 h Maillard reaction time showed the highest sedimentation volume. Based on the results, the 3:1 Na alginate/MBP rafts had the best results, and the results were within acceptable limits. Functional properties, including antioxidant properties, the Helicobacter pylori inhibition assay, the pancreatic lipase inhibition assay, and angiotensin-converting enzyme (ACE) inhibition, were investigated for rafts. The Na alginate/MBP raft has similar characteristics to Gaviscon syrup and can be used for obesity, Helicobacter pylori infection, high blood pressure, and gastric reflux.

Poliprotect vs Omeprazole in the Relief of Heartburn, Epigastric Pain, and Burning in Patients Without Erosive Esophagitis and Gastroduodenal Lesions: A Randomized, Controlled Trial

INTRODUCTION

In the treatment of upper GI endoscopy-negative patients with heartburn and epigastric pain or burning, antacids, antireflux agents, and mucosal protective agents are widely used, alone or as add-on treatment, to increase response to proton-pump inhibitors, which are not indicated in infancy and pregnancy and account for significant cost expenditure.

METHODS

In this randomized, controlled, double-blind, double-dummy, multicenter trial assessing the efficacy and safety of mucosal protective agent Poliprotect (neoBianacid, Sansepolcro, Italy) vs omeprazole in the relief of heartburn and epigastric pain/burning, 275 endoscopy-negative outpatients were given a 4-week treatment with omeprazole (20 mg q.d.) or Poliprotect (5 times a day for the initial 2 weeks and on demand thereafter), followed by an open-label 4-week treatment period with Poliprotect on-demand. Gut microbiota change was assessed.

RESULTS

A 2-week treatment with Poliprotect proved noninferior to omeprazole for symptom relief (between-group difference in the change in visual analog scale symptom score: [mean, 95% confidence interval] -5.4, -9.9 to -0.1; -6.2, -10.8 to -1.6; intention-to-treat and per-protocol populations, respectively). Poliprotect's benefit remained unaltered after shifting to on-demand intake, with no gut microbiota variation. The initial benefit of omeprazole was maintained against significantly higher use of rescue medicine sachets (mean, 95% confidence interval: Poliprotect 3.9, 2.8-5.0; omeprazole 8.2, 4.8-11.6) and associated with an increased abundance of oral cavity genera in the intestinal microbiota. No relevant adverse events were reported in either treatment arm.

DISCUSSION

Poliprotect proved noninferior to standard-dose omeprazole in symptomatic patients with heartburn/epigastric burning without erosive esophagitis and gastroduodenal lesions. Gut microbiota was not affected by Poliprotect treatment. The study is registered in Clinicaltrial.gov (NCT03238534) and the EudraCT database (2015-005216-15).

Proton pump inhibitors may enhance the risk of digestive diseases by regulating intestinal microbiota

Proton pump inhibitors (PPIs) are the most used acid-inhibitory drugs, with a wide range of applications in the treatment of various digestive diseases. However, recently, there has been a growing number of digestive complications linked to PPIs, and several studies have indicated that the intestinal flora play an important role in these complications. Therefore, developing a greater understanding of the role of the gut microbiota in PPI-related digestive diseases is essential. Here, we summarize the current research on the correlation between PPI-related digestive disorders and intestinal flora and establish the altered strains and possible pathogenic mechanisms of the different diseases. We aimed to provide a theoretical basis and reference for the future treatment and prevention of PPI-related digestive complications based on the regulation of the intestinal microbiota.

Meta-analysis of the effects of proton pump inhibitors on the human gut microbiota

Mounting evidence has linked changes in human gut microbiota to proton pump inhibitor (PPI) use. Accordingly, multiple studies have analyzed the gut microbiomes of PPI users, but PPI-microbe interactions are still understudied. Here, we performed a meta-analysis of four studies with available 16S rRNA gene amplicon sequencing data to uncover the potential changes in human gut microbes among PPI users. Despite some differences, we found common features of the PPI-specific microbiota, including a decrease in the Shannon diversity index and the depletion of bacteria from the Ruminococcaceae and Lachnospiraceae families, which are crucial short-chain fatty acid-producers. Through training based on multiple studies, using a random forest classification model, we further verified the representativeness of the six screened gut microbial genera and 20 functional genes as PPI-related biomarkers, with AUC values of 0.748 and 0.879, respectively. Functional analysis of the PPI-associated 16S rRNA microbiome revealed enriched carbohydrate- and energy-associated genes, mostly encoding fructose-1,6-bisphosphatase and pyruvate dehydrogenase, among others. In this study, we have demonstrated alterations in bacterial abundance and functional metabolic potential related to PPI use, as a basis for future studies on PPI-induced adverse effects.

Evidence for proton-pump inhibitor (PPI)-associated dysbiosis in metabolically unhealthy obesity

Obesity adversely impacts millions of American adults by predisposing them to significant health risks and further complications. Obesity is differentiated into two groups: metabolically healthy and metabolically unhealthy. In contrast to metabolically healthy counterparts, obese individuals who are metabolically unhealthy display hallmark symptoms of metabolic syndrome (e.g., hypertension, dyslipidemia, hyperglycemia, abdominal obesity). Gastroesophageal reflux disease (GERD) commonly occurs in all obese populations, as do poor dietary habits. Proton-pump inhibitors (PPIs), due to their wide availability, are most often used to treat GERD-related heartburn and other symptoms. Here, we review the evidence on how poor diet as well as short- and long-term use of PPIs adversely affect the gastrointestinal microbiota to cause dysbiosis. Key components of dysbiosis-induced metabolically unhealthy obesity (MUO) associated with PPI use include "leaky gut," systemic low-grade inflammation, and reduced amounts of short-chain fatty acids (SCFAs) such as butyrate that promote metabolic health. The benefit of using probiotics to mitigate PPI-induced dysbiosis and MUO is also discussed.

Proton pump inhibitor-induced gut dysbiosis and immunomodulation: current knowledge and potential restoration by probiotics

Proton pump inhibitors (PPIs) are the most commonly prescribed drugs for the treatment of non-erosive reflux disease (NERD), ulcers associated with non-steroidal anti-inflammatory drugs (NSAIDs), esophagitis, peptic ulcer disease (PUD), Zollinger-Ellison syndrome (ZES), gastroesophageal reflux disease (GERD), non-ulcer dyspepsia, and Helicobacter pylori eradication therapy. The drugs have the effect of inhibiting acid production in the stomach. According to research, PPIs can affect the composition of gut microbiota and modulate the immune response. Recently, there has been a problem with the over-prescription of such drugs. Although PPIs do not have many side effects, their long-term use can contribute to small intestinal bacterial overgrowth (SIBO) or C. difficile and other intestinal infections. Probiotic supplementation during PPIs therapy may provide some hope in the reduction of emerging therapy side effects. This review aims to present the most important effects of long-term PPI use and provides critical insights into the role of probiotic intervention in PPI therapy.

Gastroesophageal reflux disease in children: What’s new right now?

Gastroesophageal reflux (GER) in children is very common and refers to the involuntary passage of gastric contents into the esophagus. This is often physiological and managed conservatively. In contrast, GER disease (GERD) is a less common pathologic process causing troublesome symptoms, which may need medical management. Apart from abnormal transient relaxations of the lower esophageal sphincter, other factors that play a role in the pathogenesis of GERD include defects in esophageal mucosal defense, impaired esophageal and gastric motility and clearance, as well as anatomical defects of the lower esophageal reflux barrier such as hiatal hernia. The clinical manifestations of GERD in young children are varied and nonspecific prompting the necessity for careful diagnostic evaluation. Management should be targeted to the underlying aetiopathogenesis and to limit complications of GERD. The following review focuses on up-to-date information regarding of the pathogenesis, diagnostic evaluation and management of GERD in children.

Combination Use of First-Line Afatinib and Proton-Pump Inhibitors Reduces Overall Survival Among Patients with EGFFR Mutant Lung Cancer

Purpose

Previous retrospective studies reported that proton-pump inhibitors (PPIs) may decrease the efficacy of first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) including gefitinib and erlotinib. Afatinib had a wider soluble pH range, with possible fewer interactions with antacids. However, clinical data were limited. Thus, this study aimed to evaluate the negative impact of PPIs on afatinib.

Patients and Methods

This retrospective cohort study included patients who are newly diagnosed with non-small cell lung cancer (NSCLC) from 2014 to 2019 using the Chang Gung Research Database. We identified patients who were treated with first-line afatinib and analyzed the association between the PPI and afatinib treatment outcomes.

Results

A total of 1418 patients were treated with first-line afatinib and followed up for 6 years. First-line afatinib was administered to 918 eligible patients, and 330 had afatinib with PPIs. The combination use of PPIs and afatinib significantly decreased the overall survival (OS) compared with that of patients using afatinib only (median OS: 33.2 and 25.1 months, p < 0.01) and multivariate analyses (Combination use: hazard ratio: 1.29; 1.05-1.59, p = 0.01). The percentages of patients who were able to receive 2nd line therapy also significantly decreased in afatinib with PPI cohort.

Conclusion

The concurrent use of PPIs was associated with lower OS in patients with EGFR-mutant lung cancer under the first-line afatinib treatment but not associated with TTF.

Refractory Helicobacter pylori infection and the gastric microbiota

Background

Curing refractory Helicobacter pylori infection is difficult. In addition, there is currently no research on the gastric microbiota of refractory H. pylori infection.

Methods

We designed a clinical retrospective study involving 32 subjects divided into three groups: 1. nAGHp.a, treatment-naïve patients with H. pylori infection; 2. nAGHp.b, H. pylori-negative patients; and 3. EFHp.a, patients with refractory H. pylori infection. Gastric mucosal samples from the biobank of our research center were collected for 16S rRNA sequencing analysis and bacterial functions were predicted via PICRUSt.

Results

There were significant differences between the H. pylori- positive group and the H. pylori-negative group in species diversity, gastric microbiota structure, and bacterial function. The beneficial Lactobacillus in the H. pylori-positive group were significantly enriched compared with those in the refractory H. pylori infection group. The bacterial interaction network diagram suggested that the microbiota interactions in the refractory H. pylori infection group decreased. The gastric microbiota of the refractory H. pylori infection group was enriched in the pathways of metabolism and infectious diseases (energy metabolism, bacterial secretion system, glutathione metabolism, protein folding and associated processing, sulphur metabolism, membrane and intracellular structural molecules, lipopolysaccharide biosynthesis, ubiquinone and other terpenoid-quinone biosynthesis, inorganic ion transport and metabolism, and metabolism of cofactors and vitamins) when compared with the H. pylori-positive group without treatment based on PICRUSt analysis.

Conclusion

Significant alterations occurred in the gastric microbiota when eradication of H. pylori failed multiple times. A history of eradication of multiple H. pylori infections leads to an imbalance in the gastric mucosal microbiota to a certain extent, which was mainly reflected in the inhibition of the growth of beneficial Lactobacillus in the stomach. Patients with refractory H. pylori infection may be at a higher risk of developing gastric cancer than other H. pylori-positive patients.

Analysis of gastric microbiota and Helicobacter pylori infection in gastroesophageal reflux disease

Background

We evaluated the microbiota in the stomach of Gastroesophageal Reflux Disease (GERD) patients. We compared Erosive Reflux Disease (ERD) to gastritis and Non-erosive Reflux Disease (NERD) subjects by 16S rRNA approach on gastric biopsy specimens. A total of 197 subjects were included consisting of gastritis (68; 34.52%), ERD (55; 27.92%), and NERD (74; 37.56%). After quality filtering, 187 samples were included for OTU analysis using Qiime2.

Results

We observed a significant difference in alpha diversity (Shannon and Simpson indexes were P = 0.0016 and P = 0.017, respectively). A significant decrease in alpha diversity index was observed in NERD with Helicobacter pylori (H. pylori)-positive subjects than in gastritis (Simpson index P = 0.022; Shannon index P = 0.029), indicating a significant influence of H. pylori on the diversity in the stomach despite the diseases. In H. pylori-negative samples, alpha diversity measurement by the abundance coverage estimates (ACE) and Fisher Test revealed that ERD had significantly lower richness than gastritis and NERD groups (P = 0.00012 and P = 0.00043, respectively). Anaerobacillus sp. could only be found in ERD patients by LEFse analysis.

Conclusions

The presence of ERD could alter microbiome diversity. A negative correlation between H. pylori and ERD is shown in this microbiome study but not in NERD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13099-022-00510-3.

Characteristics of the Gut Microbiota in Japanese Patients with Premenstrual Syndrome

Purpose

The present study aimed to characterize the gut microbiota of individuals with premenstrual syndrome.

Patients and Methods

The gut microbiota of 24 Japanese women with PMS (PMS group) and 144 healthy Japanese women (control group) were compared. Analysis of the α- and β-diversities and the gut microbial composition at the genus level were performed using 16S rRNA gene sequence data obtained from stool samples.

Results

A significant difference in age was observed between the PMS and control groups; however, no significant difference was observed in BMI. The α-diversity measured using the Simpson index was significantly higher in the PMS group than the control group. Visualization of the β-diversity using non-metric multidimensional scaling and permutational multivariate analysis of variance (PERMANOVA) showed that the distance of the gut microbiota between the PMS and control groups is significantly different. Furthermore, a significant difference in the composition of the gut microbiota was observed between the PMS and control groups. At the genus level, the abundances of Collinsella, Bifidobacterium, and Blautia were significantly higher in the PMS group than in the control group. In particular, the abundance of Collinsella in the PMS group was approximately 4.5 times higher than that in the control group. To rule out the confounding effect of age in the abundances of Bifidobacterium, Blautia, and Collinsella, the gut microbiota of the PMS and control groups were compared by age group. Results showed that Collinsella had the highest effect size in participants of 30–40 years of age (mean age: 36.39 ± 4.68 years).

Conclusion

These results suggest that the PMS group possesses a characteristic gut microbiota. In particular, Collinsella was strongly associated with PMS. Since Collinsella has been reported to be associated with diet, dietary interventions such as prebiotics targeting Collinsella may be effective in preventing, improving, and alleviating PMS.

Changes to the upper gastrointestinal microbiotas of children with reflux oesophagitis and oesophageal metaplasia

Little is known of the relationships among paediatric upper gastrointestinal microbiotas, and the impact of medication use and disease on their diversity. Here, we investigated the diversity of three microbiotas in the upper gastrointestinal tract of paediatric patients in relation to each other and to host factors. Oral, oesophageal and gastric microbiotas from a prospective paediatric cohort (n=54) were profiled using the 16S rRNA gene and ITS2 amplicon sequencing. 16S rRNA gene amplicon sequencing of oesophageal biopsies from a retrospective paediatric cohort (n=96) and shotgun metagenomics data from oesophageal brushings (n=88) were employed for genomic signature validation. Bacterial diversity and composition showed substantial differences across oral, oesophageal and gastric fluid samples that were not replicated for fungi, and the presence of reflux led to increased homogeneity in the bacterial component of these three microbiotas. The oral and oesophageal microbiotas were associated with age, sex, history of oesophageal atresia and presence of oesophageal metaplasia, with the latter characterized by Prevotella enrichment. Proton pump inhibitor use was associated with increased oral bacterial richness in the gastric fluid, and this correlated with increased levels of gastric pro-inflammatory cytokines. Profiling of oesophageal biopsies from a retrospective paediatric cohort confirmed an increased Prevotella prevalence in samples with metaplasia. Analysis of metagenome-derived oesophageal Prevotella melaninogenica genomes identified strain-specific features that were significantly increased in prevalence in samples with metaplasia. Prevotella enrichment is a signature associated with paediatric oesophageal metaplasia, and proton pump inhibitor use substantially alters the paediatric gastric microenvironment.

Tandem Mass Tag Analysis of the Effect of the Anterior Cingulate Cortex in Nonerosive Reflux Disease Rats with Shugan Jiangni Hewei Granules Treatment

Objective

The current study aims to analyze the improvement mechanism of visceral hypersensitivity (VH) and targets of Shugan Jiangni Hewei granules (SJHG) for nonerosive reflux disease (NERD) treatment as well as to offer an experimental foundation for its clinical use.

Methods

Healthy male Sprague-Dawley rats (n = 36) were acquired in the current study that was further split into three groups: blank, model, and drug (SJHG). Subsequently, differentially expressed proteins and bioinformatics analysis were performed on the collected tissue samples acquired from the anterior cingulate cortex of the model and SJHG rat groups using a tandem mass tag- (TMT-) based proteomics. Eventually, the obtained data from the bioinformatic analysis was further verified through western blotting.

Results

From the bioinformatics analysis, only 64 proteins were differentially expressed between the NC and SJHG groups. These molecules were found to be highly expressed in immunological response and neural signal transmission. Finally, we confirmed three therapeutic targets of SJHG, namely, kininogen 1 (Kng1), junctional adhesion molecule A (JAM-A), and the PI3K/Akt signaling pathway.

Conclusions

SJHG is effective in treating VH, Kng1 and JAM-A may be therapeutic targets of SJHG, and the therapeutic mechanism of SJHG may be realized by influencing immune response or transmission of neural signals.

Gut Bless Your Pain—Roles of the Gut Microbiota, Sleep, and Melatonin in Chronic Orofacial Pain and Depression

Background. Increased attention has been paid to the gut–brain axis recently, but little is known so far regarding how this translates into pain susceptibility. Aim. The aim of this review is to determine whether gastroenterological disorders and sleep disorders (directly or indirectly) contribute to an increased susceptibility to depression and chronic orofacial pain. Method. A search was performed in the U.S. National Library of Medicine (PubMed) database in order to find studies published before 19 December 2021. We used the following terms: gut microbiome, OR sleep quality, OR melatonin, OR GERD, OR IBS, AND: depression OR chronic pain, in different configurations. Only papers in English were selected. Given the large number of papers retrieved in the search, their findings were described and organized narratively. Results. A link exists between sleep disorders and gastroenterological disorders, which, by adversely affecting the psyche and increasing inflammation, disturb the metabolism of tryptophan and cause excessive microglial activation, leading to increased susceptibility to pain sensation and depression. Conclusions. Pain therapists should pay close attention to sleep and gastrointestinal disorders in patients with chronic pain and depression.

Proton pump inhibitors induce changes in the gut microbiome composition of systemic lupus erythematosus patients

BACKGROUND

Currently, few studies focus on the association between gut microbiota and systemic lupus erythematosus (SLE), and much less studies consider the effect of drug usage. Proton pump inhibitors (PPIs) are commonly used to treat drug-related gastrointestinal damage in SLE patients. Therefore, the purpose of this study is to examine the gut microbiota of SLE patients using PPIs.

METHODS

Fecal samples from 20 SLE patients with PPIs (P-SLE), 20 SLE patients without PPIs (NP-SLE) and 17 healthy controls (HCs) were obtained. The structure of the bacterial community in the fecal samples was analyzed by 16S rRNA gene sequencing. Redundancy analysis (RDA) was performed to observe the relationship between clinical variables and microbiome composition in P-SLE and NP-SLE patients. Based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, functional capabilities of microbiota were estimated. Network analysis was performed to analyze the association of metabolic pathway alterations with altered gut microbiota in P-SLE and NP-SLE patients.

RESULTS

P-SLE patients exhibited increased alpha-diversity and an altered composition of the gut microbiota compared with NP-SLE patients. The alpha-diversity of NP-SLE patients was significantly lower than HCs but also of P-SLE patients, whose alpha-diversity had become similar to HCs. Compared with NP-SLE patients, the relative abundances of Lactobacillus, Roseburia, Oxalobacter, and Desulfovibrio were increased, while those of Veillonella, Escherichia, Morganella, Pseudomonas and Stenotrophomonas were decreased in P-SLE patients. RDA indicated that PPI use was the only significant exploratory variable for the microbiome composition when comparing SLE patients. KEGG analysis showed that 16 metabolic pathways were significantly different between NP-SLE and P-SLE patients. These metabolic pathways were mainly associated with changes in Escherichia, Roseburia, Stenotrophomonas, Morganella and Alipipes as determined by the network analysis.

CONCLUSIONS

PPI use is associated with an improved microbiome composition of SLE patients as it 1) increases alpha-diversity levels back to normal, 2) increases the abundance of various (beneficial) commensals, and 3) decreases the abundance of certain opportunistic pathogenic genera such as Escherichia. Validation studies with higher patient numbers are however recommended to explore these patterns in more detail.

Investigation of the impact of commonly used medications on the oral microbiome of individuals living without major chronic conditions

BACKGROUND

Commonly used medications produce changes in the gut microbiota, however, the impact of these medications on the composition of the oral microbiota is understudied.

METHODS

Saliva samples were obtained from 846 females and 368 males aged 35-69 years from a Canadian population cohort, the Atlantic Partnership for Tomorrow's Health (PATH). Samples were analyzed by 16S rRNA gene sequencing and differences in microbial community compositions between nonusers, single-, and multi-drug users as well as the 3 most commonly used medications (thyroid hormones, statins, and proton pump inhibitors (PPI)) were examined.

RESULTS

Twenty-six percent of participants were taking 1 medication and 21% were reported taking 2 or more medications. Alpha diversity indices of Shannon diversity, Evenness, Richness, and Faith's phylogenetic diversity were similar among groups, likewise beta diversity as measured by Bray-Curtis dissimilarity (R2 = 0.0029, P = 0.053) and weighted UniFrac distances (R2 = 0.0028, P = 0.161) were non-significant although close to our alpha value threshold (P = 0.05). After controlling for covariates (sex, age, BMI), six genera (Saprospiraceae uncultured, Bacillus, Johnsonella, Actinobacillus, Stenotrophomonas, and Mycoplasma) were significantly different from non-medication users. Thyroid hormones, HMG-CoA reductase inhibitors (statins) and PPI were the most reported medications. Shannon diversity differed significantly among those taking no medication and those taking only thyroid hormones, however, there were no significant difference in other measures of alpha- or beta diversity with single thyroid hormone, statin, or PPI use. Compared to participants taking no medications, the relative abundance of eight genera differed significantly in participants taking thyroid hormones, six genera differed in participants taking statins, and no significant differences were observed with participants taking PPI.

CONCLUSION

The results from this study show negligible effect of commonly used medications on microbial diversity and small differences in the relative abundance of specific taxa, suggesting a minimal influence of commonly used medication on the salivary microbiome of individuals living without major chronic conditions.

The uninvited guests of our microbiome: Helicobacter pylori and Epstein-Barr virus and their role in gastric cancerogenesis

It is well established that human body is an ecosystem for numerous microorganisms: bacteria, fungi, eukaryotic parasites, and viruses. They form a “microbiome” that under conditions of homeostasis remains in a friendly mutual relationship with the host. However, the composition and diversity of this microbe community is dynamic and can be changed under the influence of environmental factors, such as diet, antibiotic therapy, lifestyle, and the host’s genotype and immunity. The result of gut microbiome dysbiosis can lead even to cancer. The aim of this review is the description of the healthy gastrointestinal microbiome and the role of two infectious agents: Gram-negative bacteria Helicobacter pylori and Epstein-Barr virus in the development of gastric cancer in terms of gut dysbiosis. H. pylori is the most important pathogen of gastric microbiome with clear impact on its diversity. Coinfection with Epstein-Barr virus causes chronic gastritis, and the inflammatory process is significantly increased. The process of carcinogenesis begins with chronic inflammation that causes atrophic gastritis, intestinal metaplasia, dysplasia, and finally cancer. It has been proven that chronic inflammatory infection caused by infectious agents increases the risk of stomach cancer. Molecular methods that are progressively used to explore the human microbiome provide hope that this knowledge will be used for future diagnoses and therapy in the state of its dysbiosis and in cases of gastric cancer.

Proton Pump Inhibitor Use Increases Pyogenic Liver Abscess Risk: A Nationwide Cohort Study

Background/Aims

Proton pump inhibitors (PPIs) increase gastric pH and alter the gut microbiome. An increased risk for infectious diseases has been reported in PPI users. However, little is known about the association of PPI use with pyogenic liver abscess (PLA) incidence risk.

Methods

We conducted a population-based cohort study using data from a nationwide representative sample of the Korean general population followed up for 10 years (January 1, 2003 to December 31, 2013). We identified PPI prescriptions and considered PPI as a timevarying variable. Proportional hazards regression model was used for incident PLA comparing PPI use versus non-use. Propensity score matching was also conducted.

Results

During the 4 209 229 person-years of follow-up, 58 595 participants had at least 1 PPI prescription and 541 patients developed liver abscess. The age-, sex-, residential area-, and income-adjusted hazard ratio for PLA incidence with PPI use was 4.19 (95% CI, 2.54- 6.92). The association was observed in fully adjusted models (hazard ratio 3.88; 95% CI, 2.33-6.44). The positive association between PPI use and PLA was consistent in all subgroups analyzed and in propensity score matching group.

Conclusion

The present data indicate that PPI use is associated with an increased PLA risk. Therefore, it is necessary to prescribe PPIs with clear indication and to avoid improper use of PPIs.

Microbiota and Its Impact on the Immune System in COVID-19-A Narrative Review

The microbiota is of interest for the development of a therapeutic strategy against SARS-CoV-2 coronavirus disease 2019 (COVID-19) due to its impact on the host immune system. Proven communications of the gut microbiota with the pulmonary microbiota (gut-lung axis) and the pathway of neural connections between the gut and brain (gut-brain axis) may be important in the face of the pandemic. SARS-CoV-2 was shown to affect almost all organs because of the presence of a host receptor known as angiotensin converting enzyme 2 (ACE2). The ACE2 receptor is mainly present in the brush border of intestinal enterocytes, ciliary cells, and type II alveolar epithelial cells in the lungs. The transport function of ACE2 has been linked to the ecology of gut microbes in the digestive tract, suggesting that COVID-19 may be related to the gut microbiota. The severity of COVID-19 may be associated with a number of comorbidities, such as hypertension, diabetes, obesity, and/or old age; therefore, attention is also paid to multiple morbidities and the modulation of microbiota through comorbidities and medications. This paper reviews the research in the context of the state of the intestinal microbiota and its impact on the cells of the immune system during the SARS-CoV-2 pandemic.

Impact of non-antibiotic drugs on the human intestinal microbiome

INTRODUCTION

The gut microbiota is composed of trillions of microbial cells and viruses that interact with hosts. The composition of the gut microbiota is influenced by several factors including age, diet, diseases, or medications. The impact of drugs on the microbiota is not limited to antibiotics and many non-antibiotic molecules significantly alter the composition of the intestinal microbiota.

AREAS COVERED

This review focuses on the impact of four of the most widely prescribed non-antibiotic drugs in the world: Proton-pump inhibitors, metformin, statins, and non-steroidal anti-inflammatory. We conducted a systematic review by searching online databases including Medline, Web of science, and Scopus for indexed articles published in English until February 2021. We included studies assessing the intestinal microbiome alterations associated with proton pump inhibitors (PPIs), metformin, statins, and nonsteroidal anti-inflammatory drugs (NSAIDs). Only studies using culture-independent molecular techniques were included.

EXPERT OPINION

The taxonomical signature associated with non-antibiotic drugs are not yet fully described, especially in the field of metabolomic. The identification of taxonomic profiles associated a specific molecule provides information on its mechanism of action through interaction with the intestinal microbiota. Many side effects could be related to the dysbiosis induced by these molecules.

Impact of Environmental and Pharmacologic Changes on the Upper Gastrointestinal Microbiome

Diseases of the upper gastrointestinal tract have become more prevalent over time. Mechanisms of disease formation are still only partially understood. Recent literature has shown that the surrounding microbiome affects the propensity for disease formation in various parts of the upper gastrointestinal tract. A review was performed of any literature to our best knowledge concerning the effects of pharmacologic agents, environmental changes, and surgical intervention on the microbiome of the upper gastrointestinal tract. Searches of the literature were performed using specific keywords related to drugs, surgical procedures, and environmental factors. Many prescription and nonprescription drugs that are commonly used have varying effects on the upper gastrointestinal tract. Proton pump inhibitors may affect the relative prevalence of some organisms in the lower esophagus and have less effect in the proximal esophagus. Changes in the esophageal microbiome correlate with some esophageal diseases. Drugs that induce weight loss have also been shown to affect the microbiomes of the esophagus and stomach. Common surgical procedures are associated with shifts in the microbial community in the gastrointestinal tract. Environmental factors have been shown to affect the microbiome in the upper gastrointestinal tract, as geographic differences correlate with alterations in the microbiome of the gastrointestinal tract. Understanding the association of environmental and pharmacologic changes on the microbiome of the upper gastrointestinal tract will facilitate treatment plans to reduce morbidity from disease.

Treatment regimens may compromise gut-microbiome-derived signatures for liver cirrhosis

Many of the gut-microbiome-derived signatures for liver cirrhosis, especially the important ones, were likely under the influence of proton pump inhibitors (PPIs). Wu et al. suggest that drug usage is a confounding factor in metagenomics analysis that should be controlled for.

The Combined Effects of Magnesium Oxide and Inulin on Intestinal Microbiota and Cecal Short-Chain Fatty Acids

Constipation is a common condition that occurs in many people worldwide. While magnesium oxide (MgO) is often used as the first-line drug for chronic constipation in Japan, dietary fiber intake is also recommended. Dietary fiber is fermented by microbiota to produce short-chain fatty acids (SCFAs). SCFAs are involved in regulating systemic physiological functions and circadian rhythm. We examined the effect of combining MgO and the water-soluble dietary fiber, inulin, on cecal SCFA concentration and microbiota in mice. We also examined the MgO administration timing effect on cecal SCFAs. The cecal SCFA concentrations were measured by gas chromatography, and the microbiota was determined using next-generation sequencing. Inulin intake decreased cecal pH and increased cecal SCFA concentrations while combining MgO increased the cecal pH lowered by inulin and decreased the cecal SCFA concentrations elevated by inulin. When inulin and MgO were combined, significant changes in the microbiota composition were observed compared with inulin alone. The MgO effect on the cecal acetic acid concentration was less when administered at ZT12 than at ZT0. In conclusion, this study suggests that MgO affects cecal SCFA and microbiota during inulin feeding, and the effect on acetic acid concentration is time-dependent.

Microbiome of the Aerodigestive Tract in Health and Esophageal Disease

The diverse human gut microbiome is comprised of approximately 40 trillion microorganisms representing up to 1000 different bacterial species. The human microbiome plays a critical role in gut epithelial health and disease susceptibility. While the interaction between gut microbiome and gastrointestinal pathology is increasingly understood, less is known about the interaction between the microbiome and the aerodigestive tract. This review of the microbiome of the aerodigestive tract in health, and alterations in microbiome across esophageal pathologies highlights important findings and areas for future research. First, microbiome profiles are distinct along the aerodigestive tract, spanning the oral cavity to the stomach. In patients with reflux-related disease such as gastro-esophageal reflux disease, Barrett's esophagus, and esophageal adenocarcinoma, investigators have observed an overall increase in gram negative bacteria in the esophageal microbiome compared to healthy individuals. However, whether differences in microbiome promote disease development, or if these shifts are a consequence of disease remains unknown. Interestingly, use of proton pump inhibitor therapy is also associated with shifts in the microbiome, with distinct shifts and patterns along the aerodigestive tract. The relationship between the human gut microbiome and esophageal pathology is a ripe area for investigation, and further understanding of these pathways may promote development of novel targets in prevention and therapy for esophageal diseases.

Helicobacter pylori Related Diseases and Osteoporotic Fractures (Narrative Review)

Osteoporosis (OP) and osteoporotic fractures (OFs) are common multifactorial and heterogenic disorders of increasing incidence. Helicobacter pylori (H.p.) colonizes the stomach approximately in half of the world's population, causes gastroduodenal diseases and is prevalent in numerous extra-digestive diseases known to be associated with OP/OF. The studies regarding relationship between H.p. infection (HPI) and OP/OFs are inconsistent. The current review summarizes the relevant literature on the potential role of HPI in OP, falls and OFs and highlights the reasons for controversies in the publications. In the first section, after a brief overview of HPI biological features, we analyze the studies evaluating the association of HPI and bone status. The second part includes data on the prevalence of OP/OFs in HPI-induced gastroduodenal diseases (peptic ulcer, chronic/atrophic gastritis and cancer) and the effects of acid-suppressive drugs. In the next section, we discuss the possible contribution of HPI-associated extra-digestive diseases and medications to OP/OF, focusing on conditions affecting both bone homeostasis and predisposing to falls. In the last section, we describe clinical implications of accumulated data on HPI as a co-factor of OP/OF and present a feasible five-step algorithm for OP/OF risk assessment and management in regard to HPI, emphasizing the importance of an integrative (but differentiated) holistic approach. Increased awareness about the consequences of HPI linked to OP/OF can aid early detection and management. Further research on the HPI-OP/OF relationship is needed to close current knowledge gaps and improve clinical management of both OP/OF and HPI-related disorders.

[Clinical efficacy of proton pump inhibitor combined with ranitidine in the treatment of throat reflux]

Objective:To investigate the clinical effect of proton pump inhibitor combined with ranitidine on patients with laryngopharyngeal reflux. Method:Seventy patients with laryngopharyngeal reflux diagnosed in our hospital were randomly divided into group A and group B according to admission time. The difference of B symptom index, reflux symptom scale, sleep breathing test, quality of life and well-being score between the two groups were detected. Result:Before treatment, the RSI index, RFS similarity and QOLS and MUNSH scores were similar （P>0.05）. After four weeks of treatment, the group B score was 3.3±1.2, the group A score was 8.2±3.5, and the group B score was significantly lower. The RFS score of group A （6.2±2.3） was higher than that of group B （2.1±1.9, P<0.05）. The scores of QOLS and MUNSH in group B were （67.57±7.26） and （23.99±3.44）, respectively. The scores of QOLS and MUNSH in group A （50.13±10.19） and （12.21±1.47）, respectively. The results of the two groups were significantly different （P<0.05）. After treatment, the RSI index, RFS score, QOLS and MUNSH scores of the two groups were lower than those before treatment. （P<0.05）. As for the sleep respiration monitoring （PSG） results, after 4-week treatment, compared with the group A, the total sleep time of the group B was significantly increased （P<0.05）, and the number of wakefulness and wakefulness was significantly decreased. The duration of Ⅲ+Ⅳ sleep was also significantly increased, and the proportion of REM sleep time and AHI was significantly reduced （P<0.05）. Conclusion:Proton pump inhibitor combined with ranitidine is more effective and safer than single drug treatment, and can significantly improve the throat reflux symptoms.

Mucosa-associated microbiota in the jejunum of patients with morbid obesity: alterations in states of insulin resistance and metformin treatment

BACKGROUND

Stool samples have been widely used to evaluate gut microbiota; however, little is known about the composition of human small intestinal microbiota and the alterations provoked by insulin resistance.

OBJECTIVE

To describe the composition of jejunal microbiota in morbidly obese patients, as well as its link with insulin resistance and metformin treatment.

SETTING

Virgen de la Victoria University Hospital and Regional University Hospital, Málaga, Spain.

METHODS

Jejunal biopsies from 46 morbidly obese patients were analyzed by next-generation sequencing method. Patients were classified in the following 3 groups: low homeostasis model assessment of insulin resistance index (HOMA-IR) value, high HOMA-IR value, and metformin-treated type 2 diabetes patients (T2D-metf).

RESULTS

Richness (q = .011) together with Proteobacteria (W = 2), Fusobacteria (W = 2), and Bacteroidetes (W = 1) phyla were significantly higher in high HOMA-IR compared with low HOMA-IR group. At family level, several differences were found between low HOMA-IR and T2D-metf group, being the most important the higher abundance of Halomonadacea in T2D-metf group (W = 22). PICRUSt analysis showed that predicted genes involved in trimethylamine-N-oxide biosynthesis pathway could be increased in jejunal microbiota of T2D-metf group compared with the low HOMA-IR group, while indole biosynthesis pathway could be increased in the low HOMA-IR group compared with the high HOMA-IR group.

CONCLUSION

An increase in richness and an enrichment in Proteobacteria, Fusobacteria, and Bacteroidetes was observed in jejunal from morbidly obese patients with high insulin resistance. Halomonadaceae family was significantly increased in metformin-treated patients. Functional analysis of predicted metagenome suggests that trimethylamine-N-oxide biosynthesis pathway could be increased in the jejunal microbiota of T2D-meft group, while indole biosynthesis pathway could be increased in low HOMA-IR group. These results contribute to the increase in the scarce knowledge about the mucosal microbiota of the hardly accessible small intestine.

Gut microbiota in surgical and critically ill patients

Microbiota-defined as a collection of microbial organisms colonising different parts of the human body-is now recognised as a pivotal element of human health, and explains a large part of the variance in the phenotypic expression of many diseases. A reduction in microbiota diversity, and replacement of normal microbes with non-commensal, pathogenic or more virulent microbes in the gastrointestinal tract-also known as gut dysbiosis-is now considered to play a causal role in the pathogenesis of many acute and chronic diseases. Results from animal and human studies suggest that dysbiosis is linked to cardiovascular and metabolic disease through changes to microbiota-derived metabolites, including trimethylamine-N-oxide and short-chain fatty acids. Dysbiosis can occur within hours of surgery or the onset of critical illness, even without the administration of antibiotics. These pathological changes in microbiota may contribute to important clinical outcomes, including surgical infection, bowel anastomotic leaks, acute kidney injury, respiratory failure and brain injury. As a strategy to reduce dysbiosis, the use of probiotics (live bacterial cultures that confer health benefits) or synbiotics (probiotic in combination with food that encourages the growth of gut commensal bacteria) in surgical and critically ill patients has been increasingly reported to confer important clinical benefits, including a reduction in ventilator-associated pneumonia, bacteraemia and length of hospital stay, in small randomised controlled trials. However, the best strategy to modulate dysbiosis or counteract its potential harms remains uncertain and requires investigation by a well-designed, adequately powered, randomised controlled trial.

Simultaneous Assessment of Urinary and Fecal Volatile Organic Compound Analysis in De Novo Pediatric IBD

Endoscopic evaluation is mandatory in establishing the diagnosis of pediatric inflammatory bowel disease (IBD), but unfortunately carries a high burden on patients. Volatile organic compounds (VOC) have been proposed as alternative, noninvasive diagnostic biomarkers for IBD. The current study aimed to assess and compare the potential of fecal and urinary VOC as diagnostic biomarkers for pediatric IBD in an intention-to-diagnose cohort. In this cohort study, patients aged 4–17 years, referred to the outpatient clinic of a tertiary referral center under suspicion of IBD, were eligible to participate. The diagnosis was established by endoscopic and histopathologic assessment, participants who did not meet the criteria of IBD were allocated to the control group. Participants were instructed to concurrently collect a fecal and urinary sample prior to bowel lavage. Samples were analyzed by means of gas chromatography–ion mobility spectrometry. In total, five ulcerative colitis patients, five Crohn’s disease patients, and ten age and gender matched controls were included. A significant difference was demonstrated for both fecal (p-value, area under the curve; 0.038, 0.73) and urinary (0.028, 0.78) VOC profiles between IBD and controls. Analysis of both fecal and urinary VOC behold equal potential as noninvasive biomarkers for pediatric IBD diagnosis.

Duration of use of proton pump inhibitors and the risk of gastric and oesophageal cancer

BACKGROUND

There is increasing interest in the potential association between proton pump inhibitors (PPIs) and the risk of gastric and oesophageal cancer, yet the effect of duration of treatment needs clarification.

METHODS

This Swedish population-based cohort study assessed the influence of time since initiation of PPI treatment on the risk of gastric and oesophageal cancer, presented as standardised incidence ratios and 95% confidence intervals.

RESULTS

The risk of gastric and oesophageal cancer during the first year was 7-10 times higher than the background population, and remained 24-202% increased without any decrease over time after the first year.

CONCLUSION

PPI use was associated with an increased risk of gastric and oesophageal cancer and the risk remained increased over follow-up. These results support our original hypothesis that use of PPIs may be a risk factor for gastric and oesophageal cancer in the general population of maintenance users, independent of underlying indications.