Ruchi Mathur

• Cedars-Sinai Medical Center

Background Functional dyspepsia (FD) is a multifactorial disorder as its development may be based on several different pathophysiological mechanisms. Interaction of gut microbiome with the host has been proposed as a potential mechanism involved in the disease's pathogenesis. Aim/Methods We aimed to characterize microbiome profiling on duodenal lu...

Disclosure: G. Parodi: None. G. Leite: None. W. Morales: None. S.R. Weitsman: None. G.M. Barlow: None. M. Sanchez: None. M. Pimentel: None. M. Villanueva-Millan: None. M. Pimentel: None. R. Mathur: None. The gut microbiome has impacts on metabolic endocrine and reproductive functions. It is known that specific bacteria can impact host metabolism by...

Disclosure: G. Parodi: None. G. Leite: None. W. Morales: None. S.R. Weitsman: None. G.M. Barlow: None. M. Sanchez: None. M. Pimentel: None. M. Villanueva-Millan: None. M. Pimentel: None. R. Mathur: None. The gut microbiome has impacts on metabolic endocrine and reproductive functions. It is known that specific bacteria can impact host metabolism by...

This cross-sectional study investigates the association between glucagon-like peptide-1 receptor agonists and food retention during esophagogastroduodenoscopy.

Rifaximin is FDA-approved for treatment of irritable bowel syndrome with diarrhea (IBS-D), but poor solubility may limit its efficacy against microbes in the mucus layer, e.g. Escherichia coli. Here we evaluate adding the mucolytic N-acetylcysteine (NAC) to improve rifaximin efficacy. In a resazurin checkerboard assay, combining rifaximin with NAC...

Elemental diets have been employed for the management of various diseases for over 50 years, with several mechanisms mediating their beneficial effects. Yet, they are underutilized due to poor palatability, access, cost, and lack of awareness regarding their clinical efficacy. Therefore, in this review, we aimed to systematically search and review...

Objectives Gut microbiome changes are linked to obesity, but findings are based on stool data. Here, we analyzed the duodenal microbiome and serum biomarkers in subjects with normal weight, overweight, and obesity. Methods Duodenal aspirates and serum samples were obtained from subjects undergoing standard-of-care esophagogastroduodenoscopy withou...

Diabetes rates have risen to the point where 1 in 10 adults worldwide have diabetes, and obesity rates have more than tripled since 1975. These conditions are interrelated and multifactorial, and are also associated with multiple health complications. Evidence suggests that gut microbiota play critical roles in the maintenance of human health and t...

The small intestinal microbiome (SIM) is colonized by a variety of bacteria, archaea, viruses, and eukarya which contribute to the overall health of the human host. Commensal bacteria of the small intestine are crucial suppliers of essential nutrients, aid in the metabolism of indigestible carbohydrates, provide defenses against pathogenic bacteria...

Diarrhea-predominant irritable bowel syndrome (IBS-D), associated with increased intestinal permeability, inflammation, and small intestinal bacterial overgrowth, can be triggered by acute gastroenteritis. Cytolethal distending toxin B (CdtB) is produced by gastroenteritis-causing pathogens and may underlie IBS-D development, through molecular mimi...

Background We recently demonstrated that diarrhea-predominant irritable bowel syndrome (IBS-D) subjects have higher relative abundance (RA) of hydrogen sulfide (H2S)-producing Fusobacterium and Desulfovibrio species, and constipation-predominant IBS (IBS-C) subjects have higher RA of methanogen Methanobrevibacter smithii. Aims In this study, we in...

Studies using stool samples suggest that non-sugar sweetener (NSS) consumption affects gut microbiome composition. However, stool does not represent the entire gut. We analyzed the duodenal luminal microbiome in subjects consuming non-aspartame non-sugar sweeteners (NANS, N = 35), aspartame only (ASP, N = 9), and controls (CON, N = 55) and the stoo...

Disclosure: R. Santos: None. G. Parodi: None. G. Leite: None. W. Morales: None. S.R. Weitsman: None. G. Barlow: None. I. Rivera: None. M. Sanchez: None. D. Flor: None. L. Choi: None. S.L. Gonzales: None. F. Faria: None. M. Villanueva-Millan: None. M. Pimentel: None. R. Mathur: None. Polycystic ovary syndrome (PCOS) is a major endocrine disorder aff...

Disclosure: N. Tal: None. G. Leite: None. G. Barlow: None. W. Morales: None. R. de Souza Santos: None. M. Pimentel: None. R. Mathur: None. Varied gut microbial profiles and functional potentials may increase or decrease cardiovascular (CVD) disease risk. Trimethylamine (TMA), a known bacterial metabolite associated with red meat ingestion, is linke...

Disclosure: G. Leite: None. N. Tal: None. G. Barlow: None. W. Morales: None. R. de Souza Santos: None. M. Rashid: None. A. Hosseini: None. M. Pimentel: None. R. Mathur: None. Attenuated somatotroph axis function correlates inversely with age-related comorbidities in both animal and human studies. Mechanisms by which GH and IGF-1 may promote aging i...

Background The coronavirus disease 2019 (COVID-19) global pandemic necessitated many severe lifestyle changes, including lockdowns, social distancing, altered food consumption and exercise patterns, and extensive hygiene practices. These extensive changes may have affected the human gut microbiome, which is highly influenced by lifestyle. Aims To...

Background and aims: Despite accelerated research in small intestinal bacterial overgrowth (SIBO), questions remain regarding optimal diagnostic approaches and definitions. Here, we aim to define SIBO using small bowel culture and sequencing, identifying specific contributory microbes, in the context of gastrointestinal symptoms. Methods: Subjec...

Introduction: Non-alcoholic fatty liver disease (NAFLD) is a multifactorial, wide-spectrum liver disorder. Small intestinal bacterial overgrowth (SIBO) is characterized by an increase in the number and/or type of colonic bacteria in the upper gastrointestinal tract. SIBO, through energy salvage and induction of inflammation, may be a pathophysiolo...

Diabetes represents one of the most significant, and rapidly escalating, global health care crises we face today. Diabetes already affects one tenth of the world’s adults, more than 537 million people, numbers which have already tripled since 2000 and which are estimated to reach 643 million by 2030. Type 2 diabetes (T2D), the most prevalent form,...

Introduction Antibiotics are over-used in healthcare, but little is known regarding their effects on cortisol levels in healthy individuals. Furthermore, antibiotics influence the gut microbiome, but the interrelationships between these drugs, cortisol and the microbiome are unknown. Here, we exposed the gut microbiome of rats to a multi-drug antib...

Objectives: Irritable bowel syndrome (IBS) includes diarrhea-predominant (IBS-D) and constipation-predominant (IBS-C) subtypes. We combined breath testing and stool microbiome sequencing to identify potential microbial drivers of IBS subtypes. Methods: IBS-C and IBS-D subjects from two randomized controlled trials (NCT03763175, NCT04557215) were...

Gut microbiome composition is different in males and females, but sex is rarely considered when prescribing antibiotics, and sex-based differences in gut microbiome recovery following antibiotic treatment are poorly understood. Here, we compared the effects of broad-spectrum antibiotics on both the stool and small bowel microbiomes in male and fema...

Tobacco use is the leading preventable cause of cancer, and affects the respiratory, oral, fecal, and duodenal mucosa-associated microbiota. However, the effects of smoking on the duodenal luminal microbiome have not been studied directly. We aimed to compare the duodenal luminal microbiome in never-smokers, current smokers, and ex-smokers who quit...

Background: In humans, methane (CH4) is exclusively produced by the intestinal microbiota and has been implicated in several conditions including cardiovascular disease. After microbial production of CH4 in the gut, it steadily crosses into the systemic circulation and reaches the lungs where it can be detected in the exhaled breath, as a surrogat...

Introduction: Stool form assessment relies on subjective patient reports using the Bristol Stool Scale (BSS). In a novel smartphone application (app), trained artificial intelligence (AI) characterizes digital images of users' stool. Here we evaluate this AI for accuracy in assessing stool characteristics. Methods: Subjects with diarrhea-predomi...

Objective: Hormone therapy (HT) is used to treat menopause-related conditions and symptoms. The small intestine plays key roles in metabolic and endocrine function, but the effects of HT on the small intestinal microbiome are unknown. Here, we characterize duodenal microbiome differences, and the effects of HT, in postmenopausal women. Methods:...

Introduction: A 2-hour breath test is the gold standard for diagnosing intestinal methanogen overgrowth (IMO). This method can be cumbersome especially if used repetitively to monitor treatment response. Therefore, we aimed to assess the reliability of a fasting single methane measurement (SMM) in diagnosing IMO and its utility as a biomarker to m...

Gut microbiome changes have been associated with human ageing and implicated in age-related diseases including Alzheimer’s disease and Parkinson’s disease. However, studies to date have used stool samples, which do not represent the entire gut. Although more challenging to access, the small intestine plays critical roles in host metabolism and immu...

Background Proton pump inhibitor (PPI) use is extremely common. PPIs have been suggested to affect the gut microbiome, and increase risks of Clostridium difficile infection and small intestinal bacterial overgrowth (SIBO). However, existing data are based on stool analyses and PPIs act on the foregut.AimsTo compare the duodenal and stool microbiome...

Background Upper gastrointestinal (GI) disorders and abdominal pain afflict between 12 and 30% of the worldwide population and research suggests these conditions are linked to the gut microbiome. Although large-intestine microbiota have been linked to several GI diseases, the microbiota of the human small intestine and its relation to human disease...

Mitochondrial antiviral signaling (MAVS) protein mediates innate antiviral responses, including responses to certain coronaviruses such as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We have previously shown that ultraviolet-A (UVA) therapy can prevent virus-induced cell death in human ciliated tracheal epithelial cells (HTEpC) in...

Gut microbial diversity decreases with aging, but existing studies have used stool samples, which do not represent the entire gut. We analyzed the duodenal microbiome in 251 subjects aged 18–35 (n = 32), 36–50 (n = 41), 51–65 (n = 96), and 66–80 (n = 82). Decreased duodenal microbial diversity in older subjects is associated with combinations of ch...

Background An important clinical feature of coronavirus disease 2019 (COVID-19) is hypercytokinemia (cytokine storm). We previously showed that narrow band ultraviolet-A (NB-UVA) treatment salvages coronavirus (CoV)-229E-infected human tracheal cells, and that daily endotracheal NB-UVA therapy reduced severe acute respiratory syndrome coronavirus 2...

IntroductionOur previous preclinical experiments show that under specific and monitored conditions, ultraviolet A (UVA) exposure reduces certain bacteria, fungi, and viruses including coronavirus-229E without harming mammalian columnar epithelial cells. The goal of this study was to evaluate the safety and effects of narrow-band UVA therapy adminis...

Mitochondrial antiviral signaling (MAVS) protein mediates innate antiviral responses, including responses to certain coronaviruses such as severe acute respiratory syndrome coronavirus-2 ( SARS-CoV-2 ). We have previously shown that ultraviolet-A (UVA) therapy can prevent virus-induced cell death in human ciliated tracheal epithelial cells (HTEpC)...

Background: Promising preclinical experiments show that, under specific and monitored conditions, ultraviolet-A (UVA) exposure reduces certain bacteria, fungi, and viruses including coronavirus-229E without harming mammalian columnar epithelial cells. We aimed to evaluate the safety and effects of UVA therapy administered by a novel device via endo...

Background Most gut microbiome studies have been performed using stool samples. However, the small intestine is of central importance to digestion, nutrient absorption, and immune function, and characterizing its microbial populations is essential for elucidating their roles in human health and disease.AimsTo characterize the microbial populations...

Antimicrobial-resistant and novel pathogens continue to emerge, outpacing efforts to contain and treat them. Therefore, there is a crucial need for safe and effective therapies. Ultraviolet-A (UVA) phototherapy is FDA-approved for several dermatological diseases but not for internal applications. We investigated UVA effects on human cells in vitro,...

Small intestinal bacterial overgrowth (SIBO) is highly prevalent and is associated with numerous gastrointestinal disorders, but the microbes involved remain poorly defined. Moreover, existing studies of microbiome alterations in SIBO have utilized stool samples, which are not representative of the entire gastrointestinal tract. Therefore, we aimed...

Objectives To compare the appendiceal microbiomes and examine the prevalence of Campylobacter species in the appendices of adult subjects with confirmed acute non-perforated appendicitis and controls with healthy appendices. Design Archived samples of formalin-fixed paraffin-embedded appendiceal tissues were obtained from 50 consecutive female sub...

Context Epidemiologic studies of polycystic ovary syndrome (PCOS) are limited, especially in populations where diagnostic resources are less available. In these setting, an accurate, low-cost screening tool would be invaluable. Objective To test the use of a simple questionnaire to identify women at increased risk for PCOS and androgen excess (AE)...

There is no clear study identifying the microbiome of the appendix. However, in other diverticular conditions, such as diverticulosis, methanogens appear important. We investigated whether patients who had undergone appendectomies had decreased levels of exhaled methane (CH4). Consecutive patients who underwent breath testing (BT) from November 200...

BACKGROUND A great proportion of Inflammatory Bowel Disease (IBD) patients exhibit persistent gastrointestinal symptoms such as diarrhea and abdominal pain that are not always related to mucosal inflammation. In this setting, irritable bowel syndrome (IBS) is the most frequent superimposed condition and ROME IV criteria have limited diagnostic accu...

Background: The human small intestine plays a central role in the processes of digestion and nutrient absorption. However, characterizations of the human gut microbiome have largely relied on stool samples, and the associated methodologies are ill-suited for the viscosity and low microbial biomass of small intestine samples. As part of the REIMAGI...

INTRODUCTION The small intestine is an understudied frontier of microbiome research. While aspiration during endoscopy is considered the gold standard to assess small bowel bacteria, the tools for sterile retrieval are primitive and poorly validated. Moreover, endoscopic aspiration is time consuming and prone to contamination. Inspired by plants’ a...