Salivary Peptide Protects Against E. Coli Diarrhea

MedicalResearch.com Interview with:

Esther Bullitt, Ph.D. Associate Professor Dept. of Physiology & Biophysics Boston University School of Medicine Boston, MA  02118-2526

Dr. Bullitt

Esther Bullitt, Ph.D.
Associate Professor
Dept. of Physiology & Biophysics
Boston University School of Medicine
Boston, MA  02118-2526 

MedicalResearch.com: What is the background for this study?

Response:      We know that saliva has properties that allow us to swallow easily, and to help prevent gum disease and infections in the mouth. But is that really the only use for the 1-2 liters (1-2 quarts) of saliva we produce every day?  We decided to test whether a component of saliva, Histatin-5, can help prevent diarrheal disease (Traveler’s Diarrhea by Enterotoxigenic Escherichia coli (ETEC)) that is caused by bacteria commonly found in contaminated food and water.

ETEC are bacteria that have hundreds of thin hair-like fibers on their surface, called pili. These bacteria bind specifically to the surface of the gut using these pili, and the bacteria need to stay bound long enough to initiate disease. Studies by Mike Levine’s group in the 1970’s showed that pili are necessary for enterotoxigenic Escherichia coli (ETEC) to cause disease. No adhesion, no disease.

One aid to remaining bound is the unwinding and rewinding of the pili. These helical fibers can unwind up to 8 times their original length, acting as shock absorbers during fluid flow.   Continue reading

Vagotomy May Point To Gut Origin of Parkinson’s Disease

MedicalResearch.com Interview with:

Karin Wirdefeldt, MD, PhD</strong> Associate professor Karolinska Institutet Stockholm, Sweden

Dr. Wirdefeldt

Karin Wirdefeldt, MD, PhD
Associate professor
Karolinska Institutet
Stockholm, Sweden

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: It has been hypothesized that Parkinson’s disease may start in the gut and spread to the brain via the vagal nerve. We found that people who had a truncal vagotomy (ie, the nerve trunk fully resected) at least 5 years earlier were less likely to develop Parkinson’s disease compared to people without vagotomy or people who had a selective vagotomy (ie, only branches of the nerve resected).

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Without Fiber, Gut Bacteria Begin To Eat Our Intestinal Lining

MedicalResearch.com Interview with:

Mahesh Desai, PhD Principal Investigator Allergology - Immunology - Inflammation Research Unit Department of Infection and Immunity Luxembourg Institute of Health Luxembourg

Dr. Mahesh Desai

MedicalResearch.com: What is the background for this study?

Response: Over the last few decades, our intake of dietary fiber has fallen drastically mainly due to the consumption of processed food, which has been connected to increased cases of intestinal diseases including colon cancer and inflammatory bowel disease. The gut microbiota is essential for us as it allows our body to digest dietary fiber contained in fruits and vegetables, that could otherwise not be processed. Changed physiologies and abundances of the gut microbiota following a fiber-deprived diet have been commonly linked to several intestinal diseases. However, the mechanisms behind these connections have remained poorly understood.

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Germline Mutation in VSIG10L and Familial Barrett Neoplasia

MedicalResearch.com Interview with:

Amitabh Chak, MD University Hospitals Case Medical Ctr Cleveland, OH, 44106

Dr-Amitabh-Chak

Amitabh Chak, MD
University Hospitals Case Medical Ctr
Cleveland, OH, 44106

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: About 20 years ago we discovered that Barrett’s esophagus and esophageal cancer aggregate in a small proportion of families suggesting there might be a genetic basis to these complex diseases. As we started looking at these families, we identified a rare family with multiple members who had Barrett’s esophagus and multiple members who had passed away from esophageal cancer at a young age. Advances in exome sequencing have now allowed us to identify a mutation in a gene whose function is not known that predisposes this family to develop Barrett’s esophagus. Functional studies suggest that this gene, VSIG10L, is involved in maturation of normal squamous esophagus.

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Gut and Brain Communicate To Drive Irritable Bowel Syndrome

MedicalResearch.com Interview with:

Laureate Professor Nicholas J. Talley, MBBS (Hons.)(NSW), MD (NSW), PhD (Syd), MMedSci (Clin Epi)(Newc.), FRACP, FAFPHM, FAHMS, FRCP (Lond. & Edin.), FACP, FACG, AGAF, FAMS, FRCPI (Hon), GAICD Pro Vice-Chancellor, Global Research, University of Newcastle, Australia Professor of Medicine, Faculty of Health and Medicine, University of Newcastle, Australia

Prof. Nicholas Talley

Laureate Professor Nicholas J. Talley, MBBS (Hons.)(NSW), MD (NSW), PhD (Syd), MMedSci (Clin Epi)(Newc.), FRACP, FAFPHM, FAHMS, FRCP (Lond. & Edin.), FACP, FACG, AGAF, FAMS, FRCPI (Hon), GAICD
Pro Vice-Chancellor, Global Research,
University of Newcastle, Australia
Professor of Medicine, Faculty of Health and Medicine, University of Newcastle, Australia
President, Royal Australasian College of Physicians
Chair, Committee of Presidents of Medical Colleges
Hon. Treasurer, Australian Academy of Health and Medical Sciences
Editor-in-Chief, Medical Journal of Australia
Senior Staff Specialist, John Hunter Hospital, Newcastle, Australia
Professor of Medicine and Professor of Epidemiology, Joint Supplemental Consultant Gastroenterology and Health Sciences Research, Mayo Clinic, Rochester, MN, USA

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Functional gastrointestinal diseases (FGIDs) like the irritable bowl syndrome (IBS) are very common, cause major distress including pain and psychological dysfunction, impact on quality of life and drive high health care costs. We speculated that there are two distinct types of functional gastrointestinal disease that others have not recognized.

For example, IBS in a subgroup may first begin with gut symptoms (pain, diarrhea, constipation, bloating etc) in those free of psychological distress and only later does new onset anxiety or depression develop, implicating gut disease as the primary driver of the entire symptom complex (a gut-to-brain disease). On the other hand, we speculated there is another quite different subgroup where disease begins with anxiety or depression and only later do new onset gut symptoms develop, and this is likely primarily a central nervous system cause (probably through the stress system), or a brain-to-gut disease. This is exactly what we found, with gut disease occurring first followed by new onset psychological distress in about two thirds of people from the community over a one year follow-up.

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Acid Suppression Reduces Risk of Esophageal Cancer in Barrett’s Esophagus

MedicalResearch.com Interview with:

Dr. Aaron Thrift

Dr. Aaron Thrift

Aaron Peter Thrift, Ph.D
Assistant Professor
Duncan Cancer Center
Department of Medicine, Gastroenterology Section
Baylor College of Medicine
Houston, TX, US

MedicalResearch.com: What is the background for this study? What are the main findings? 

Dr. Thrift: Patients with Barrett’s esophagus are at significantly higher risk of developing esophageal adenocarcinoma. Due to the continued rise in incidence of esophageal adenocarcinoma attention has turned to chemoprevention as a method to delay or halt the progression of Barrett’s esophagus to neoplasia, including invasive cancer. Acid suppressive medications, such as proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RAs), are commonly used in patients with gastroesophageal reflux disease (GERD), the primary risk factor for Barrett’s esophagus.

We contacted a nested case-control study involving 311 patients with Barrett’s esophagus who developed esophageal adenocarcinoma (cases) and 856 matched controls (patients with Barrett’s esophagus but who did not develop esophageal adenocarcinoma). Compared to never users, we found that Barrett’s esophagus patients taking PPIs and H2RAs had 69% and 45% lower risk of esophageal adenocarcinoma, respectively. The associations were independent of other risk factors for progression, including concomitant use of nonsteroidal anti-inflammatory drugs and statins.
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Antibiotics Increase Oxygen in Bowel, Allowing Salmonella To Thrive

MedicalResearch.com Interview with:

Andreas J. Bäumler, Ph.D Editor, Infection and Immunity Associate Editor, PLOS Pathogens Section Editor, EcoSal Plus Professor, Department of Medical Microbiology and Immunology Vice Chair of Research University of California, Davis School of Medicine Davis, California

Dr. Andreas Bäumler

Andreas J. Bäumler, Ph.D
Editor, Infection and Immunity
Associate Editor, PLOS Pathogens
Section Editor, EcoSal Plus
Professor, Department of Medical Microbiology and Immunology
Vice Chair of Research
University of California, Davis School of Medicine
Davis, California

 

MedicalResearch.com: What is the background for this study? What are the main findings?

Dr. Bäumler: Antibiotics are generally beneficial for treating bacterial infection, but paradoxically a history of antibiotic therapy is a risk factor for developing Salmonella food poisoning.  Our study reveals the mechanism by which antibiotics increase susceptibility to Salmonella infection.

Antibiotics deplete beneficial microbes from the gut, which normally provide nutrition to the cells lining our large bowel, termed epithelial cells. Depletion of microbe-derived nutrients causes our epithelial cells to switch their energy metabolism from respiration to fermentation, which in turn increases the availability of oxygen at the epithelial surface. The resulting increase in oxygen diffusion into the gut lumen drives a luminal expansion of Salmonella by respiration. Through this mechanism, antibiotics help Salmonella to breath in the gut.

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Intestinal Pathogens Change the Microbiome, Cause E. Coli To “Bloom”

Shannon D. Manning, Ph.D., M.P.H. Dept. of Microbiology and Molecular Genetics Michigan State University E. Lansing, MI 48824

Dr. Manning

MedicalResearch.com Interview with:
Shannon D. Manning, Ph.D., M.P.H
.
Dept. of Microbiology and Molecular Genetics
Michigan State University
E. Lansing, MI 48824

Medical Research: What is the background for this study? What are the main findings?
Dr. Manning: Diarrheal disease is a leading cause of morbidity and mortality in children under the age of five and is commonly caused by many different bacterial pathogens.

We have observed that infection with four different bacterial pathogens (Salmonella, Shigella, Shiga toxin-producing E. coli, and Campylobacter) all induce the proliferation of a population of microbes, namely Escherichia, which are already present in the gut of healthy individuals.

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More Evidence That Gut Bacteria May Affect Progression Of Metabolic Disease

Adil Mardinoglu, PhD Assistant Professor of Systems BiologyScience for Life Laboratory Royal Institute of Technology (KTH) Stockholm, SwedenMedicalResearch.com Interview with:
Adil Mardinoglu, PhD
Assistant Professor of Systems BiologyScience for Life Laboratory
Royal Institute of Technology (KTH)
Stockholm, Sweden

Medical Research: What is the background for this study? What are the main findings?

Dr. Mardinoglu: The functional output and diversity of the gut microbiota are important modulators for the development of various human disorders. Obesity, type 2 diabetes (T2D), atherosclerosis, non-alcoholic fatty liver disease (NAFLD) as well as the opposite end of the spectrum, for example, malnutrition have been associated with dysbiosis in the human gut microbiota. In our study, we investigated the interactions between the gut microbiota, host tissues of the gastrointestinal tract and other peripheral tissues as well as diet which are known to be highly relevant for the health of the host.

Through integration of high throughput experimental data, we revealed that the microbiota in the small intestine consumes glycine which is one of the three amino acids required for the synthesis of the glutathione. In order to confirm our predictions, we measured the level of the amino acids in the portal vein of the mice. We observed lower level of glycine in liver and colon tissues, and this indicated that the gut microbiota regulates glutathione metabolism not only in the small intestine but also in the liver and the colon tissues.

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Disruptive Gastrointestinal Problems Common In Infants and Toddlers

Miranda van Tilburg, PhD Associate Professor of Medicine University of North CarolinaMedicalResearch.com Interview with:
Miranda van Tilburg, PhD

Associate Professor of Medicine
University of North Carolina

Medical Research: What is the background for this study? What are the main findings?

Dr. van Tilburg: Functional gastrointestinal disorders are common in children, adolescents and adults but little is known about the prevalence in infants and toddlers.  Functional gastrointestinal disorders in infancy include disorders such as regurgitation, colic, and dyschezia, while functional gastrointestinal disorders in toddlers include functional constipation, functional diarrhea, functional dyspepsia, cyclic vomiting, and rumination. Of these disorders only colic and regurgitation have received much research attention. Prevalence, cause and consequences of most functional gastrointestinal disorders in infants and toddlers are largely unknown. We set out to determine the prevalence in the US by asking a representative sample of mothers to report on their child’s symptoms. Our study found that 27% of infants and toddlers may suffer from a functional gastrointestinal disorder. Among infants, regurgitation was the most common disorder and among toddlers constipation. Despite functional gastrointestinal disorders generally being more prevalent in older girls and adult women, no sex differences were found in this age group. Toddlers who suffer from a functional gastrointestinal disorders had lower quality of life and made more health care visits.

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